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Chakraborty S, Stotts G, Rush C, Hogan MJ, Dowlatshahi D. Dynamic 'Spot Sign' Resolution following INR Correction in a Patient with Warfarin-Associated Intracerebral Hemorrhage. Case Rep Neurol 2011; 3:154-9. [PMID: 21792352 PMCID: PMC3142097 DOI: 10.1159/000330304] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Hematoma expansion in intracerebral hemorrhage is associated with poor clinical outcome. The ‘spot sign’ is a radiological marker that is associated with hematoma expansion, and thought to represent active extravasation of contrast. This case demonstrates the use of dynamic CT angiography in identifying the time-dependent appearance of a spot sign in a patient with warfarin-associated intracerebral hemorrhage. Repeat imaging is also presented which verified cessation of the spot sign after INR correction.
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Affiliation(s)
- S Chakraborty
- Department of Radiology (Neuroradiology), University of Ottawa and Ottawa Hospital Research Institute, Ottawa, Ont., Canada
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202
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Abstract
Abstract
177Lu is presently considered to be a potential radionuclide for the development of agents for radionuclide therapy owing to its favorable nuclear decay characteristics [T
1/2 = 6.65 d, E
β(max) = 0.497 MeV, E
γ
= 113 KeV (6.4%) and 208 KeV (11%)]. While the long half-life of this promising radioisotope offers distinct logistic advantage, particularly, in countries having limited reactor facilities, the feasibility of its large-scale production with adequate specific activity and excellent radionuclidic purity in medium flux research reactors constitute yet another desirable feature. Extensive studies have been carried out to optimize the production of this isotope, with high specific activity and radionuclidic purity by the (n,γ) route using the highest available flux and the optimum irradiation time. The gradual evolution of clin ical grade 177LuCl3 as a new radiochemical, ready for commercial deployment by Radiopharmaceuticals Division, Bhabha Atomic Research Centre, to nuclear medicine centers all over India was accomplished in 2010 in a stepwise manner with the commencement of the production of high specific activity 177Lu from enriched target in 2001. Research on 177Lu has demonstrated its immense potential in radiotherapeutic applications, a direct outcome of which has resulted in indigenous development of two agents viz.
177Lu-EDTMP and 177Lu-DOTA-TATE presently being evaluated in human patients for palliative care of bone pain due to skeletal metastases and treatment of malignancies of neuroendocrine origin, respectively. Using locally produced 177Lu, the radiolabeling of a plethora of other molecules with potential applicability in radiation synovectomy and targeted therapy of malignant tumors have been successfully demonstrated. A few of these agent such as a novel 177Lu-labeled porphyrin has shown considerable promise in initial studies and is presently evaluated. In the present article, our research efforts toward standardization of production methodology of 177Lu in high specific activity and its utilization in the devel opment of agents for targeted radiotherapy are being reported.
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Affiliation(s)
| | - Tapas Das
- Bhabha Atomic Research Centre, Radiopharmaceuticals Division, Trombay, Mumbai 400085, Indien
| | - S. Chakraborty
- Bhabha Atomic Research Centre, Radiopharmaceuticals Division, Trombay, Mumbai 400085, Indien
| | - Meera Venkatesh
- Bhabha Atomic Research Centre, Radiopharmaceuticals Division, Trombay, Mumbai 400085, Indien
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203
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Patil VM, Patel FD, Chakraborty S, Oinam AS, Sharma SC. Can point doses predict volumetric dose to rectum and bladder: a CT-based planning study in high dose rate intracavitary brachytherapy of cervical carcinoma? Br J Radiol 2011; 84:441-8. [PMID: 21511749 DOI: 10.1259/bjr/33758793] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE Point doses, as defined by the International Commission on Radiation Units and Measurements (ICRU), are classically used to evaluate doses to the rectum and bladder in high dose rate intracavitary brachytherapy (HDR-ICBT) in cervical cancer. Several studies have shown good correlation between the ICRU point doses and the volumetric doses to these organs. In the present study we attempted to evaluate whether this correlation could be used to predict the volumetric doses to these organs. METHODS A total of 150 HDR-ICBT insertions performed between December 2006 and June 2008 were randomly divided into two groups. Group A (n=50) was used to derive the correlation between the point and volumetric doses using regression analysis. This was tested in Group B (n=100) insertions using studentised residuals and Bland-Altman plots. RESULTS Significant correlations were obtained for all volumetric doses and ICRU point doses for rectum and bladder in Group A insertions. The strongest correlation was found for the dose to 2 cc volumes (D(2cc)). The correlation coefficients for bladder and rectal D(2cc) versus the respective ICRU point doses were 0.82 and 0.77, respectively (p<0.001). Statistical validation of equations generated in Group B showed mean studentised residual values of 0.001 and 0.000 for the bladder and rectum. However, Bland-Altman analysis showed that the error range for these equations for bladder and rectum were ±64% and ±41% of the point A dose, respectively, which makes these equations unreliable for clinical use. CONCLUSION Volumetric imaging is essential to obtain proper information about volumetric doses.
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Affiliation(s)
- V M Patil
- Department of Radiotherapy, Cobalt Block, Post Graduate Institute of Medical Education and Research, Chandigarh 160012, India
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204
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Hauke RJ, Tarantolo SR, Batra S, Chakraborty S. Second primary cancers and their prognostic significance in patients with renal cell carcinoma. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.7_suppl.377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
377 Background: To study the overall and site specific risk and prognostic significance of second primary cancers (SPC) in patients diagnosed with renal cell carcinoma (RCC). Methods: The Surveillance Epidemiology and End Results (SEER) database was queried for all patients with RCC as the first cancer and one or more SPC (1973-2006). SPC diagnosed within 1 month of diagnosis of RCC or at autopsy/death were excluded. Deidentified information was obtained to analyze the effect of SPC on overall survival (OS) of RCC patients. Results: A total of 3,795 patients with RCC and ≥ 1 SPC were identified. The ratio of observed/expected cases (O/E ratio) of RCC and ≥ 1 SPCs was 1.18 (95% C.I. 1.15-1.22), significantly greater than the general population (p<0.05). The overall age-adjusted rate of SPC was 0.6 per 100,000 and rate of SPCs was higher in males and in blacks. The O/E ratio of SPCs was significantly higher in younger patients (6.6 vs. 1.3 and 1.13 for those aged <30, 30-59 and ≥60 yrs respectively), in blacks (1.38 vs. 1.15 in whites), for larger tumors (1.3, 1.2 and 1.05 for tumors <5cm, 5-<10cm and ≥10cm in diameter), and those who did not receive radiation. The risk was similar for both genders. There was variation in the site-specific risk of SPC depending on age at time of RCC diagnosis, gender, race, size of the tumor and presence or lack of radiation therapy. Patients with SPC had longer OS than those with RCC as the only primary tumor on univariate but not multivariate analysis. Older age (≥60yrs), radiation therapy, and a short interval (<12 mo) between the diagnosis of RCC and a SPC were associated with significantly shorter OS in RCC patients with SPC on multivariate analysis. Conclusions: Our comprehensive analysis of SPCs in patients with RCC as the first primary malignancy using SEER data suggests that about 10% of RCC patients develop SPC and that several patient, tumor and treatment-related factors affect the risk of SPC at specific sites. Further, SPC can adversely influence the prognosis of patients with RCC, especially those >60 years old, receiving radiation or diagnosed with a SPC within 1 year after RCC diagnosis. These results may have significance in planning surveillance strategies to improve the survival of patients with RCC. No significant financial relationships to disclose.
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Affiliation(s)
- R. J. Hauke
- Nebraska Cancer Specialists, Omaha, NE; Eppley Cancer Center, Omaha, NE; University of Nebraska Medical Center, Omaha, NE
| | - S. R. Tarantolo
- Nebraska Cancer Specialists, Omaha, NE; Eppley Cancer Center, Omaha, NE; University of Nebraska Medical Center, Omaha, NE
| | - S. Batra
- Nebraska Cancer Specialists, Omaha, NE; Eppley Cancer Center, Omaha, NE; University of Nebraska Medical Center, Omaha, NE
| | - S. Chakraborty
- Nebraska Cancer Specialists, Omaha, NE; Eppley Cancer Center, Omaha, NE; University of Nebraska Medical Center, Omaha, NE
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205
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Rachagani S, Senapati S, Chakraborty S, Ponnusamy MP, Kumar S, Smith LM, Jain M, Batra SK. Activated KrasG¹²D is associated with invasion and metastasis of pancreatic cancer cells through inhibition of E-cadherin. Br J Cancer 2011; 104:1038-48. [PMID: 21364589 PMCID: PMC3065271 DOI: 10.1038/bjc.2011.31] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Background: Pancreatic cancer (PC) harbours an activated point mutation (KrasG12D) in the Kras proto-oncogene that has been demonstrated to promote the development of PC. Methods: This study was designed to investigate the effect of the oncogenic KrasG12D allele on aggressiveness and metastatic potential of PC cells. We silenced the oncogenic KrasG12D allele expression in CD18/HPAF and ASPC1 cell lines by stable expression of shRNA specific to the KrasG12Dallele. Results: The KrasG12D knockdown cells exhibited a significant decrease in motility (P<0.0001), invasion (P<0.0001), anchorage-dependent (P<0.0001) and anchorage-independent growth (P<0.0001), proliferation (P<0.005) and an increase in cell doubling time (P<0.005) in vitro and a decrease in the incidence of metastases upon orthotopic implantation into nude mice. The knockdown of the KrasG12D allele led to a significant increase in the expression of E-cadherin (mRNA and protein) both in vitro and in vivo. This was associated with a decrease in the expression of phoshpo-ERK-1/2, NF-κB and MMP-9, and transcription factors such as δEF1, Snail and ETV4. Furthermore, the expression of several proteins involved in cell survival, invasion and metastasis was decreased in the KrasG12D knockdown cells. Conclusions: The results of this study suggest that the KrasG12D allele promotes metastasis in PC cells partly through the downregulation of E-cadherin.
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Affiliation(s)
- S Rachagani
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
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206
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Abstract
The "spot sign", first described in 2007, has shown that a focal area of contrast extravasation within an intracerebral haematoma (ICH) can be correlated with haematoma expansion. We describe a case where time-resolved dynamic CT angiography (dCTA) shows the appearance of the "spot sign" only in later images. This finding highlights the importance of timing of the static CT angiogram which, if performed too early, might result in a false-negative diagnosis.
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Affiliation(s)
- S Chakraborty
- Department of Medical Imaging, Division of Neuro-imaging, University of Ottawa, The Ottawa Hospital, Ottawa, Ontario, Canada.
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207
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Ponnusamy MP, Lakshmanan I, Jain M, Das S, Chakraborty S, Dey P, Batra SK. Erratum: MUC4 mucin-induced epithelial to mesenchymal transition: a novel mechanism for metastasis of human ovarian cancer cells. Oncogene 2010. [DOI: 10.1038/onc.2010.472] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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208
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Bhattacharya T, Chakraborty S, Banerjee DK. Heavy metal uptake and its effect on macronutrients, chlorophyll, protein, and peroxidase activity of Paspalum distichum grown on sludge-dosed soils. Heavy metal uptake and its effect on P. distichum. Environ Monit Assess 2010; 169:15-26. [PMID: 19760086 DOI: 10.1007/s10661-009-1146-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2009] [Accepted: 08/18/2009] [Indexed: 05/28/2023]
Abstract
This study assessed the heavy metal (Cr, Mn, Ni, Cu, Zn, and Pb) uptake and its effect on biochemical parameters in Paspalum distichum, a wetland plant. Sludge collected from Bhalswa waste dump, New Delhi, was used as heavy metal source and dosed in different proportions viz. 20%, 40%, 60%, and 80% to the garden soil. The plants accumulated metals mostly in belowground organs. The metal accumulation followed the order: Cr>Mn>Cu>Zn>Ni>Pb. The range of heavy metal concentration in tissue of belowground organs after 180 days of growth was 1,778.65-4,288.01 ppm Cr, 828.11-1,360 ppm Mn, 236.52-330.07 ppm Ni, 155.79-282.35 ppm Cu, 27.05-91.16 ppm Zn, and 27.09-50.87 ppm Pb. The biochemical parameters viz. chlorophyll and protein contents and peroxidase (POD) activity exhibited no considerable adverse effect indicating the plants' tolerance towards heavy metals. The high POD activity and synthesis of new protein bands at high sludge-dosed plants were also in support of this fact.
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Affiliation(s)
- Tanushree Bhattacharya
- Department of Environmental Science and Technology, Institute of Science and Technology for Advanced Studies and Research, Vallabh Vidyanagar, Anand, 388120, Gujarat, India.
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209
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Bhattacharjee D, Hussain SA, Chakraborty S, Schoonheydt RA. Effect of nano-clay platelets on the J-aggregation of thiacyanine dye organized in Langmuir-Blodgett films: a spectroscopic investigation. Spectrochim Acta A Mol Biomol Spectrosc 2010; 77:232-237. [PMID: 20541457 DOI: 10.1016/j.saa.2010.05.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Revised: 05/10/2010] [Accepted: 05/15/2010] [Indexed: 05/29/2023]
Abstract
In this paper we report the effect of the incorporation of nano-dimensional clay platelets, laponite, on the J-aggregation of a thiacyanine dye N,N'-dioctadecyl thiacyanine perchlorate (NK) assembled into Langmuir-Blodgett (LB) monolayers. pi-A isotherms and atomic force microscopic studies confirm the successful incorporation of clay platelets into the Langmuir monolayer of NK. J-aggregates of NK remain present in LB films lifted at lower as well as higher surface pressures in the absence of laponite clay platelets. However, with the incorporation of clay platelets, J-aggregates are formed only in LB films lifted at higher surface pressure of 30 mN/m and totally absent in the films lifted at lower surface pressures of 10 and 15 mN/m. This may be due to the formation of nano-trapping level by overlapping of clay platelets at higher surface pressure. NK molecules may get squeezed to these nano-trapping to form J-aggregates.
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Affiliation(s)
- D Bhattacharjee
- Department of Physics, Tripura University, Suryamaninagar 799130, Tripura, India
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210
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Chakraborty S, Eldridge P, Nahser HC. Cerebral haemorrhage from a remote varix in the venous outflow of an arteriovenous malformation treated successfully by embolisation. Br J Radiol 2010; 83:e129-34. [PMID: 20603396 DOI: 10.1259/bjr/30362699] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
We describe a case of intracerebral haemorrhage in the temporal lobe arising from a distal varix related to the venous outflow of an ipsilateral frontal arteriovenous malformation (AVM). AVM itself and associated arterial aneurysms are well-known risk factors for haemorrhage. In this patient, haemorrhage had occurred from a distal varix. This is the first reported case of successful endovascular embolisation of a frontal AVM with spontaneous regression of an associated remote varix. [corrected].
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Affiliation(s)
- S Chakraborty
- Department of Neuroradiology, The Walton Center for Neuroradiology and Neurosurgery, Liverpool UK.
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211
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212
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Dinesh Suresh P, Kumar V, Sripriya R, Chakraborty S, Meikap B. Performance characteristics of pilot plant dense media hydrocyclone for beneficiation of coal and 3-D CFD simulation. Chem Eng Sci 2010. [DOI: 10.1016/j.ces.2010.05.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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213
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Obanor F, Erginbas-Orakci G, Tunali B, Nicol JM, Chakraborty S. Fusarium culmorum is a single phylogenetic species based on multilocus sequence analysis. Fungal Biol 2010; 114:753-65. [PMID: 20943185 DOI: 10.1016/j.funbio.2010.07.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2009] [Revised: 04/30/2010] [Accepted: 07/05/2010] [Indexed: 10/19/2022]
Abstract
Fusarium culmorum is a major pathogen of wheat and barley causing head blight and crown rot in cooler temperate climates of Australia, Europe, West Asia and North Africa. To better understand its evolutionary history we partially sequenced single copy nuclear genes encoding translation elongation factor 1-α (TEF), reductase (RED) and phosphate permease (PHO) in 100 F. culmorum isolates with 11 isolates of Fusarium crookwellense, Fusarium graminearum and Fusarium pseudograminearum. Phylogenetic analysis of multilocus sequence (MLS) data using Bayesian inference and maximum parsimony analysis showed that F. culmorum from wheat is a single phylogenetic species with no significant linkage disequilibrium and little or no lineage development along geographic origin. Both MLS and TEF and RED gene sequence analysis separated the four Fusarium species used and delineated three to four groups within the F. culmorum clade. But the PHO gene could not completely resolve isolates into their respective species. Fixation index and gene flow suggest significant genetic exchange between the isolates from distant geographic regions. A lack of strong lineage structure despite the geographic separation of the three collections indicates a frequently recombining species and/or widespread distribution of genotypes due to international trade, tourism and long-range dispersal of macroconidia. Moreover, the two mating type genes were present in equal proportion among the F. culmorum collection used in this study, leaving open the possibility of sexual reproduction.
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Affiliation(s)
- Friday Obanor
- CSIRO Plant Industry, 306 Carmody Road, St Lucia, Queensland 4067, Australia.
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214
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Chakraborty S, Bhattacharya T, Patel TN, Tiwari KK. Biodegradation of phenol by native microorganisms isolated from coke processing wastewater. J Environ Biol 2010; 31:293-296. [PMID: 21046999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The present investigation was undertaken to assess the biodegradation of phenol by native bacteria strains isolated from coke oven processing wastewater. The strains were designated ESDSPB1, ESDSPB2 and ESDSPB3 and examined for colony morphology Gram stain characters and biochemical tests. Phenol degrading performance of all the strains was evaluated initially. One of the strains namely ESDSPB2 was found to be highly effective for the removal of phenol, which was used as sole carbon and energy source. From an initial concentration of 200 mg I(-1) it degraded to 79.84 +/- 1.23 mg l(-1). In turn the effect of temperature (20 to 45 degrees C), pH (5-10) and glucose concentration (0, 0.25 and 0.5%) on the rate of phenol degradation by that particular strain was investigated. Observations revealed that the rate of phenol biodegradation was significantly affected by pH, temperature of incubation and glucose concentration. The optimal conditions for phenol removal were found to be pH of 7 (84.63% removal), temperature, 30 degrees C (76.69% removal) and 0.25% supplemented glucose level (97.88% removal). The main significance of the study is the utilization of native bacterial strains from the waste water itself having potential of bioremediation.
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Affiliation(s)
- S Chakraborty
- Department of Biological and Environmental Science, N.V. Patel College of Pure and Applied Sciences, V.V. Nagar 388 120, India.
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215
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Miller DM, Fox R, Atreja A, Moore S, Lee JC, Fu AZ, Jain A, Saupe W, Chakraborty S, Stadtler M, Rudick RA. Using an automated recruitment process to generate an unbiased study sample of multiple sclerosis patients. Telemed J E Health 2010; 16:63-8. [PMID: 20064056 DOI: 10.1089/tmj.2009.0078] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The objective of this study was to test the efficiency of an automated recruitment methodology developed as a component of a practical controlled trial to assess the benefits of a Web-based personal health site to guide self-management of multiple sclerosis symptoms called Mellen Center Care On-line. We describe the study's automated recruitment methodology using clinical and administrative databases and assess the comparability between subjects who completed informed consent (IC) forms, and individuals who were invited to participate but did not reply, designated as patient nonresponders (PNR). The IC and PNR groups were compared on demographics, number of physician or advanced practice nurse/physician assistant visits during the 12 months prior to the initial invitation, and level of disability as measured by the Charlson Comorbidity Index (CCI). Out of a total dynamic potential pool of 2,421 patients, 2,041 had been invited to participate, 309 had become ineligible to participate during the study, and 71 individuals remained in the pool at the end of recruitment. The IC group had a slightly greater proportion of females. Both groups were predominantly white with comparable marital status. The groups had comparable mean household income, education level, and commercial insurance. The computed mean CCI was similar between the groups. The only significant difference was that the PNR group had fewer clinic visits in the preceding 12 months. The subjects were highly representative of the target population, indicating that there was little bias in our selection process despite a constantly changing pool of eligible individuals.
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Affiliation(s)
- Deborah M Miller
- Mellen Center for Treatment and Research in Multiple Sclerosis, Neurological Institute, Cleveland Clinic, Cleveland, Ohio 44195, USA.
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216
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Begum YA, Chakraborty S, Chowdhury A, Ghosh AN, Nair GB, Sack RB, Svennerholm AM, Qadri F. Isolation of a bacteriophage specific for CS7-expressing strains of enterotoxigenic Escherichia coli. J Med Microbiol 2010; 59:266-272. [DOI: 10.1099/jmm.0.014795-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) is the most common bacterial cause of childhood diarrhoea in Bangladesh. Among the virulence factors of ETEC, toxins and colonization factors (CFs) play a major role in pathogenesis. Unlike Vibrio cholerae, the relationship between ETEC and ETEC-specific phages is poorly understood and the possible role of ETEC phages in the evolution of ETEC strains in the environment is yet to be established. This study was designed specifically to isolate phages that are specific for ETEC virulence factors. Among the 49 phages isolated from 12 different surface water samples, 13 were tested against 211 ETEC strains collected from clinical and environmental sources. One phage, designated IMM-001, showed a significant specificity towards CS7 CF as it attacked all the CS7-expressing ETEC. Electron microscopic analyses showed that the isolated phage possessed an isomeric hexagonal head and a long filamentous tail. An antibody blocking method and phage neutralization assay confirmed that CS7 pilus is required for the phage infection process, indicating the role of CS7 fimbrial protein as a potential receptor for IMM-001. In summary, this study showed the presence of a lytic phage in environmental water that is specific for the CS7 CF of ETEC.
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Affiliation(s)
- Y. A. Begum
- International Centre for Diarrhoeal Disease Research, Bangladesh, GPO Box 128, Dhaka 1000, Bangladesh
| | - S. Chakraborty
- International Centre for Diarrhoeal Disease Research, Bangladesh, GPO Box 128, Dhaka 1000, Bangladesh
| | - A. Chowdhury
- International Centre for Diarrhoeal Disease Research, Bangladesh, GPO Box 128, Dhaka 1000, Bangladesh
| | - A. N. Ghosh
- National Institute of Cholera and Enteric Diseases, Kolkata 700 010, India
| | - G. B. Nair
- National Institute of Cholera and Enteric Diseases, Kolkata 700 010, India
| | - R. B. Sack
- Department of International Health, The Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - A.-M. Svennerholm
- Department of Medical Microbiology and Immunology, The Sahlgrenska Academy at Göteborg University, Box 435, S-40530 Göteborg, Sweden
| | - F. Qadri
- International Centre for Diarrhoeal Disease Research, Bangladesh, GPO Box 128, Dhaka 1000, Bangladesh
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217
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Chakraborty S, Garcia R. Optical-ellipsometric study of the nematic-to-smectic transition in 8CB films adsorbed on silicon. Phys Rev E Stat Nonlin Soft Matter Phys 2010; 81:031702. [PMID: 20365746 DOI: 10.1103/physreve.81.031702] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2009] [Revised: 12/23/2009] [Indexed: 05/29/2023]
Abstract
The nematic-to-smectic-A (NA) transition in 8CB (4-octyl-4'-cyanobiphenyl) is especially interesting because experimentally, it has been observed to be second order, but theoretically, it has been predicted that it must have a latent heat. The effect on the NA transition due to confinement in an adsorbed film has hitherto not been investigated. Previous study of adsorbed 8CB films on silicon for coverages less than 100 nm showed the existence of a broad coexistence region, identified by the formation of thick and thin islands on the surface that extends between the bulk NA and the isotropic-to-nematic transition temperatures. In this paper, optical and ellipsometric measurements of 8CB films as a function of temperature are used to identify the location of the NA transition in the film in relation to the coexistence region. The NA transition temperature in the film is found to occur at 32.2+/-0.4 degrees C independent of film thickness for films between 62 to 270 nm thick, based on the decrease in the film anisotropy. This decrease in the anisotropy is found to be surprisingly abrupt. For thicknesses below 62 nm, the NA transition line is joined to the thin-thick coexistence region found previously.
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Affiliation(s)
- S Chakraborty
- Department of Physics, Worcester Polytechnic Institute, Worcester, Massachusetts 01609, USA
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218
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Hussain SA, Chakraborty S, Bhattacharjee D, Schoonheydt RA. Fluorescence Resonance Energy Transfer between organic dyes adsorbed onto nano-clay and Langmuir-Blodgett (LB) films. Spectrochim Acta A Mol Biomol Spectrosc 2010; 75:664-670. [PMID: 20018558 DOI: 10.1016/j.saa.2009.11.037] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2009] [Revised: 11/12/2009] [Accepted: 11/17/2009] [Indexed: 05/28/2023]
Abstract
In this communication we investigate two dyes N,N'-dioctadecyl thiacyanine perchlorate (NK) and octadecyl rhodamine B chloride (RhB) in Langmuir and Langmuir-Blodgett (LB) films with or with out a synthetic clay laponite. Observed changes in isotherms of RhB in absence and presence of nano-clay platelets indicate the incorporation of clay platelets onto RhB-clay hybrid films. AFM images confirm the incorporation of clay into hybrid films. FRET is observed in clay dispersion and LB films with and without clay. Efficiency of energy transfer is maximum in LB films with clay.
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Affiliation(s)
- Syed Arshad Hussain
- Department of Physics, Tripura University, Suryamaninagar 799130, Tripura, India.
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Chakraborty D, Krishna GSR, Chakraborty S, Meikap BC. Hydrodynamic Characteristics of a Sparged Gas−Liquid Contactor for Fine Bubble Generation. Ind Eng Chem Res 2009. [DOI: 10.1021/ie901322e] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- D. Chakraborty
- R&D Division, Tata Steel, Jamshedpur, 831003, India, Department of Chemical Engineering, Indian Institute of Technology (IIT), Kharaghpur, PO: Kharagpur Technology, West Bengal, 721302, India, and School of Chemical Engineering, Faculty of Engineering, Howard College, University of Kwazulu-Natal, King George V. Avenue, Durban 4041, South Africa
| | - G. Siva Rama Krishna
- R&D Division, Tata Steel, Jamshedpur, 831003, India, Department of Chemical Engineering, Indian Institute of Technology (IIT), Kharaghpur, PO: Kharagpur Technology, West Bengal, 721302, India, and School of Chemical Engineering, Faculty of Engineering, Howard College, University of Kwazulu-Natal, King George V. Avenue, Durban 4041, South Africa
| | - S. Chakraborty
- R&D Division, Tata Steel, Jamshedpur, 831003, India, Department of Chemical Engineering, Indian Institute of Technology (IIT), Kharaghpur, PO: Kharagpur Technology, West Bengal, 721302, India, and School of Chemical Engineering, Faculty of Engineering, Howard College, University of Kwazulu-Natal, King George V. Avenue, Durban 4041, South Africa
| | - B. C. Meikap
- R&D Division, Tata Steel, Jamshedpur, 831003, India, Department of Chemical Engineering, Indian Institute of Technology (IIT), Kharaghpur, PO: Kharagpur Technology, West Bengal, 721302, India, and School of Chemical Engineering, Faculty of Engineering, Howard College, University of Kwazulu-Natal, King George V. Avenue, Durban 4041, South Africa
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Chakraborty S, Ghoshal S, Patil V, Oinam A, Suresh S. Acute Toxicities Experienced during Simultaneous Integrated Boost Intensity-modulated Radiotherapy in Head and Neck Cancers — Experience from a North Indian Regional Cancer Centre. Clin Oncol (R Coll Radiol) 2009; 21:676-86. [DOI: 10.1016/j.clon.2009.07.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2009] [Revised: 07/27/2009] [Accepted: 07/28/2009] [Indexed: 11/25/2022]
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Abstract
The preferential accumulation of porphyrins in malignant tumor cells has been adequately documented. Hence, porphyrin derivatives radiolabeled with a suitable therapeutic radionuclide could be envisaged as potential agents for targeted tumor radiotherapy. Working in this direction, we have radiolabeled a porphyrin derivative, namely, 5,10,15,20-tetrakis[3,4-bis(carboethoxymethyleneoxy)phenyl]-porphyrin, synthesized in-house, with 109Pd [E
β(max)=1.12 MeV, E
γ=88 keV 3.6(%), T
1/2 = 13.7 h]. The envisaged rationale towards designing of this agent is based on the assumption that 109Pd would complex with the tetrapyrrole donor array constituting the porphyrin core, thereby providing a highly stable chelated complex, and the peripheral ester groups would impart optimum lipophilicity needed for sufficiently high tumor accumulation and retention therein. 109Pd was produced with a specific activity of ∼1.85 GBq/mg and radionuclidic purity of 100% by the thermal neutron bombardment of enriched (98% in 108Pd) metallic Pd target at a flux of 3×1013 n/cm2s1 for 3 d. The porphyrin derivative was synthesized by a multi-step reaction and characterized by normal spectroscopic techniques. 109Pd complex of the synthesized porphyrin derivative was prepared with excellent radiochemical purity (>98%) and the complex was observed to be stable upto 24 h at room temperature. Biodistribution studies carried out in Swiss mice bearing fibrosarcoma tumors revealed good tumor uptake [(5.28±1.46)% injected activity (IA)/g] within 30 min post-injection (p.i.). The complex exhibited favorable tumor/blood and tumor/muscle ratios [1.69±0.23 and 5.00±1.54, respectively at 3 h p.i.], albeit with high liver uptake throughout the time of study (>20% IA).
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Singh AK, Mishra KK, Chattopadhyay B, Chakraborty S. Biological and molecular characterization of a begomovirus associated with yellow mosaic vein mosaic disease of pumpkin from Northern India. Virus Genes 2009; 39:359-70. [PMID: 19705268 DOI: 10.1007/s11262-009-0396-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2009] [Accepted: 08/11/2009] [Indexed: 11/25/2022]
Abstract
The biological and molecular properties of Squash leaf curl China virus from Varanasi, India (SLCCNV-IN[IN:Var:Pum]) were characterized. SLCCNV-IN[IN:Var:Pum] could be transmitted by grafting and through whitefly transmission. The complete DNA-A and DNA-B components were amplified through PCR using specific DNA-A and DNA-B primers. The DNA-A of the isolate was comprised of 2,738 nucleotides, encoding typical six open reading frames, and DNA-B of 2,704 nucleotides, encoding two ORFs. Genome organization of the isolate was typical of an old world bipartite begomovirus. Comparisons showed that DNA-A and its intergenic region have the highest sequence identity (97.6 and 97.4%, respectively) with the SLCCNV-IN[IN:Luc:Pum]; (DQ026296). This data suggested that the isolate is a same begomovirus species for which the name Squash leaf curl China virus-India[India:Varanasi:Pumpkin] is proposed. DNA-B showed maximum sequence identity (89.2%) with SLCCNV-IN[IN:Coi:Pum] (AY184488). Phylogenetic analysis of the present isolate showed close relationship to other cucurbit-infecting geminiviruses. This is the first evidence of occurrence of the bipartite Squash leaf curl China virus associated with severe yellow mosaic disease of pumpkin in northern India.
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Affiliation(s)
- A K Singh
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
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Chakraborty S, Sengupta R, Dasgupta S, Mukhopadhyay R, Bandyopadhyay S, Joshi M, Ameta SC. Synthesis and characterization ofin situsodium-activated and organomodified bentonite clay/styrene-butadiene rubber nanocomposites by a latex blending technique. J Appl Polym Sci 2009. [DOI: 10.1002/app.30146] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Chakraborty S, Pandit J, Srinatha A. Development of Extended Release Divalproex Sodium Tablets Containing Hypdrophobic and Hydrophilic Matrix. Curr Drug Deliv 2009; 6:291-6. [DOI: 10.2174/156720109788680822] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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226
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Kumari P, Chattopadhyay B, Singh AK, Chakraborty S. A New Begomovirus Species Causing Tomato Leaf Curl Disease in Patna, India. Plant Dis 2009; 93:545. [PMID: 30764166 DOI: 10.1094/pdis-93-5-0545b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
During December of 2007, a severe leaf curl disease of tomato (ToLCD) occurred in tomato-growing areas in the Patna District of Bihar, India. Viral DNA was isolated from symptomatic tomato plants (2) and begomovirus association was confirmed by PCR using DNA-A degenerate primers (3). Isolated viral DNA was restricted with KpnI and full-length genome was cloned in pUC18. DNA-β was amplified using degenerate primers (1) and cloned in pTZ57RT. Partial tandem repeats of viral genome and DNA-β could infect Nicotiana benthamiana and tomato through Agrobacterium-mediated inoculation. Infected test plants exhibited typical symptoms characteristic of ToLCD. Full-length viral genome (GenBank Accession No. EU862323) consists of 2,752 nt and showed the highest identity (85.8%) with Tomato leaf curl Laos virus-[Laos] (GenBank Accession No. AF195782). The satellite DNA-β component (GenBank Accession No. EU862324) consists of 1,349 nt and showed the highest identity (75.8%) with Tomato leaf curl Joydebpur betasatellite (GenBank Accession No. AJ966244). On the basis of the ICTV species demarcation criteria of 89% of DNA-A sequence identity, the present isolate was considered as a new begomovirus species and named Tomato leaf curl Patna virus (ToLCPaV). Since the isolated DNA-β satellite shares less than 78% identity, it is considered a new species of betasatellite and the name, Tomato leaf curl Patna betasatellite (ToLCPaB) is proposed. These results show that severe ToLCD in Patna is caused by a newly identified species of begomovirus and betasatellite. References: (1) R. W. Briddon et al. Mol. Biotechnol 20:315, 2002. (2) S. Chakraborty et al. Phytopathology 93:1485, 2003. (3) S. D. Wyatt and J. K. Brown. Phytopathology 86:1288, 1996.
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Affiliation(s)
- P Kumari
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - B Chattopadhyay
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - A K Singh
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - S Chakraborty
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
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227
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Shaukat MU, Dean P, Khanna SP, Lachab M, Chakraborty S, Linfield EH, Davies AG. Generation of Bessel beams using a terahertz quantum cascade laser. Opt Lett 2009; 34:1030-1032. [PMID: 19340209 DOI: 10.1364/ol.34.001030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We report the generation of Bessel beams using polytetrafluoroethene conical lenses and a quantum cascade laser emitting at 2.8 THz. The formation of a central beam spot that retains its size over distances exceeding the characteristic Rayleigh range is demonstrated, and the power transport properties of these beams are compared with those obtained using parabolic reflectors. These lenses could provide an attractive alternative to parabolic reflectors for terahertz imaging applications where a large depth of focus and/or efficient and controllable coupling of radiation onto a small target are desirable.
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Affiliation(s)
- M U Shaukat
- School of Electronic and Electrical Engineering, University of Leeds, Leeds, UK
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228
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Wong DM, Prabhu A, Chakraborty S, Tan G, Massicotte EM, Cooper R. Cervical spine motion during flexible bronchoscopy compared with the Lo-Pro GlideScope. Br J Anaesth 2009; 102:424-30. [PMID: 19193652 DOI: 10.1093/bja/aep002] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND The most appropriate device for tracheal intubation in patients with potential cervical spine injury remains controversial. We hypothesized that the Lo-Pro GlideScope (LP-G) videolaryngoscope would not cause significantly greater cervical spine movement than fibreoptic bronchoscopy even in the non-immobilized spine. METHODS Twenty-eight healthy adults requiring intubation for radiographic procedures were randomized to either the LP-G or the flexible bronchoscope (FB) devices. Continuous fluoroscopy was used to assess cervical spine movement during tracheal intubation. The point of maximum movement was compared with baseline for change in angulation between Occiput (Occ)-C1, Occ-C2, Occ-C4, Occ-C5, C1-2, C2-4, and C4-5. Measurements were made by two independent observers. The change in angulation was also measured for tongue pull and jaw thrust, manoeuvres for enlarging the pharyngeal space, before FB intubation. RESULTS LP-G resulted in greater cervical extension compared with FB for every angle calculated, statistically significant between Occ-C1 (P<0.05), Occ-C2 (P<0.05), and Occ-C4 (P<0.01). Tongue pull resulted in significantly less cervical spine motion than FB intubation at Occ-C1, Occ-C2, Occ-C4, and Occ-C5 (P<0.05). When jaw thrust was added to tongue pull, there was a tendency for greater movement than FB intubation at Occ-C1, Occ-C2, and Occ-C3. This was statistically significant at Occ-C1 and Occ-C3 (P<0.05) for one of the two observers. CONCLUSIONS During intubation under general anaesthesia, LP-G resulted in greater cervical movement than FB when no cervical immobilization was used in adults without cervical disease. Airway manoeuvres performed before FB, especially jaw thrust, also resulted in cervical spine movement.
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Affiliation(s)
- D M Wong
- Department of Anaesthesia, Toronto Western Hospital, Canada.
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Lum C, Chakraborty S, Schlossmacher M, Santos M, Mohan R, Sinclair J, Sharma M. Vertebral artery dissection with a normal-appearing lumen at multisection CT angiography: the importance of identifying wall hematoma. AJNR Am J Neuroradiol 2009; 30:787-92. [PMID: 19164438 DOI: 10.3174/ajnr.a1455] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE CT angiography (CTA) is widely used and may be the only vascular imaging technique ordered for emergent evaluation of neurovascular disease. With thin-section multisection CTA, the resolution of vessel wall imaging has improved. We describe cases of acute vertebral artery dissection (VAD) in which the only abnormality on CTA was a characteristic thickening of the wall of the V3 portion of the vertebral artery (VA). The arterial lumen at the dissection site was normal in caliber. This type of dissection is easily overlooked if only lumen-opacifying studies such as contrast MR angiography (MRA) or conventional angiography are performed. We highlight the importance of recognizing this finding, the "suboccipital rind" sign, in the V3 portion, a segment commonly affected in VAD. The purpose of our study was to review the CTA imaging characteristics of patients with VAD in the V3 portion compared with normal controls. MATERIALS AND METHODS Our imaging data base was reviewed for cases of acute VAD and the presence of a "suboccipital rind" sign. A control group of 50 patients was randomly recruited from a group of patients undergoing CTA. The VA luminal diameter, the wall thickness (total diameter-luminal diameter), and the ratio of luminal diameter/total diameter were measured along 5 adjacent V3 segments and were compared between the 2 groups. RESULTS There was no evidence of luminal tapering or narrowing in the dissected VAs compared with controls (P = .1). The average wall thickness of the dissection group was 2.96 mm greater than that for the control group (P < .001; 95% confidence interval, 2.6-3.3). There was a significant difference in the ratio of lumen diameter/lumen+wall diameter in dissected segments compared with controls (P < .001). CONCLUSIONS Cross-sectional vascular imaging is often performed with multisection helical CTA for a variety of concerns, some without neurologic symptoms. Our study confirms that in cases of the "suboccipital rind" sign, the lumen appears normal in caliber, with wall thickening as the only imaging sign of VAD. In our center, this clinically occult VAD would influence management, with patients usually treated with antiplatelet agents. We caution against using only luminal-opacifying techniques such as contrast-enhanced MRA or conventional angiography to exclude VAD because they are limited in the evaluation of mural hematoma.
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Affiliation(s)
- C Lum
- Department of Diagnostic Imaging-Diagnostic and Interventional Neuroradiology Section, Ottawa Hospital, Ottawa, Ontario, Canada.
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Tiwari KK, Dwivedi S, Mishra S, Srivastava S, Tripathi RD, Singh NK, Chakraborty S. Phytoremediation efficiency of Portulaca tuberosa rox and Portulaca oleracea L. naturally growing in an industrial effluent irrigated area in Vadodra, Gujrat, India. Environ Monit Assess 2008; 147:15-22. [PMID: 18193484 DOI: 10.1007/s10661-007-0093-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2007] [Accepted: 11/12/2007] [Indexed: 05/25/2023]
Abstract
Phytoremediation is a novel, solar-driven and cost-effective technology for the remediation of heavy metal contaminated environments through exploitation of plants ability to accumulate heavy metals in their harvestable shoot parts. In the present investigation, we collected plants of two species of Portulaca i.e. P. tuberosa and P. oleracea from field sites in Vadodra, Gujrat, India. At one site, field was being irrigated with industrial effluent while at other with tube well water. Analysis of heavy metals was performed in industrial effluent, tube well water, soils irrigated with them, and in different parts viz., roots, stem, leaves and flowers of the plant samples. Industrial effluent and soil irrigated with it had very high level of heavy metals (Fe, Zn, Cd, Cr and As) as compared to the tube well water and soil irrigated with that. Plants of both the species growing in effluent irrigated soils showed high accumulation of metals in all plant parts with the maximum being in roots and the least in flowers. Interestingly, both species of Portulaca hyperaccumulated more than one heavy metal viz., Cd, Cr and As. The total shoot concentrations (microg g(-1) dw) of Cd, Cr and As in P. tuberosa were 1,571, 7,957 and 3,118, respectively while in P. oleracea, these were 1,128, 7,552 and 2,476, respectively. Portulaca plants have good biomass and high regeneration potential; hence appear to be suitable for the remediation of effluent (metal) contaminated areas.
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Affiliation(s)
- K K Tiwari
- Sophisticated Instrumentation Centre for Applied Research and Testing, Sardar Patel Centre for Science and Technology, Vallabh, Vidyanagar, Anand, Gujrat, 388120, India
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Chakraborty S, Vijayan K, Nair CV, Santra SC, Bhattacharya T. Isolation and characterization of high quality DNA from marine benthic macroalgae. J Environ Biol 2008; 29:907-910. [PMID: 19297990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The isolation of high quality DNA is essential for many molecular biology applications including polymerase chain reaction (PCR) and endonuclease restriction digestion based techniques. An easy and inexpensive protocol has been developed for extracting genomic DNA from seven species of algae viz. Lola capillaries, Enteromorpha intestinalis, Ulva lactuca and Rhizoclonium sp belonging to Chlorophyceae, Catenella nipae, Polysiphonia mollis belonging to Rhodophyceae and Dictyota ceylanica belonging to Phaeophyceae group were collected from the coastal regions of Sunderban delta in West Bengal, India dominantly growing on mud flats, bark of different mangrove trees, pneumatophores, stilt roots, concrete surfaces, wooden and bamboo poles, sides of the boats and other water vehicles inundated during high tides. The DNA was found suitable for restriction endonuclease digestion and PCR amplification with randomely amplified polymorphic DNA (RAPD) primers. The A260/A280 ratio of 1.15 0.14 to 1.94 indicated little contamination from proteins and polysaccharides. The PCR amplification with RAPD primers showed its suitability in PCR based techniques and the restriction digestion with Eco RV confirmed its suitability for hybridization based techniques. The protocol is equally good for isolating DNA from both fresh as well as preserved materials.
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Affiliation(s)
- S Chakraborty
- N.V. Patel College of Pure and Applied Sciences, Vallabh Vidyanagar 388 120, India.
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232
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van Geen A, Radloff K, Aziz Z, Cheng Z, Huq M, Ahmed K, Weinman B, Goodbred S, Jung H, Zheng Y, Berg M, Trang P, Charlet L, Metral J, Tisserand D, Guillot S, Chakraborty S, Gajurel A, Upreti B. Comparison of arsenic concentrations in simultaneously-collected groundwater and aquifer particles from Bangladesh, India, Vietnam, and Nepal. Appl Geochem 2008; 23:3019-3028. [PMID: 19884967 PMCID: PMC2630228 DOI: 10.1016/j.apgeochem.2008.07.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
One of the reasons the processes resulting in As release to groundwater in southern Asia remain poorly understood is the high degree of spatial variability of physical and chemical properties in shallow aquifers. In an attempt to overcome this difficulty, a simple device that collects groundwater and sediment as a slurry from precisely the same interval was developed in Bangladesh. Recently published results from Bangladesh and India relying on the needle-sampler are augmented here with new data from 37 intervals of grey aquifer material of likely Holocene age in Vietnam and Nepal. A total of 145 samples of filtered groundwater ranging in depth from 3 to 36 m that were analyzed for As (1-1000 mug/L), Fe (0.01-40 mg/L), Mn (0.2-4 mg/L) and S (0.04-14 mg/L) are compared. The P-extractable (0.01-36 mg/kg) and HCl-extractable As (0.04-36 mg/kg) content of the particulate phase was determined in the same suite of samples, in addition to Fe(II)/Fe ratios (0.2-1.0) in the acid-leachable fraction of the particulate phase. Needle-sampler data from Bangladesh indicated a relationship between dissolved As in groundwater and P-extractable As in the particulate phase that was interpreted as an indication of adsorptive equilibrium, under sufficiently reducing conditions, across 3 orders of magnitude in concentrations according to a distribution coefficient of 4 mL/g. The more recent observations from India, Vietnam and Nepal show groundwater As concentrations that are often an order of magnitude lower at a given level of P-extractable As compared to Bangladesh, even if only the subset of particularly reducing intervals characterized by leachable Fe(II)/Fe >0.5 and dissolved Fe >0.2 mg/L are considered. Without attempting to explain why As appears to be particularly mobile in reducing aquifers of Bangladesh compared to the other regions, the consequences of increasing the distribution coefficient for As between the particulate and dissolved phase to 40 mL/g for the flushing of shallow aquifers of their initial As content are explored.
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Affiliation(s)
- A. van Geen
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York, USA
- Corresponding author:
| | - K. Radloff
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York, USA
| | - Z. Aziz
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York, USA
| | - Z. Cheng
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York, USA
| | - M.R. Huq
- Department of Geology, University of Dhaka, Bangladesh
| | - K.M. Ahmed
- Department of Geology, University of Dhaka, Bangladesh
| | - B. Weinman
- Earth & Environmental Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - S. Goodbred
- Earth & Environmental Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - H.B. Jung
- Queens College, City University of New York, Flushing, New York, USA
| | - Y. Zheng
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York, USA
- Queens College, City University of New York, Flushing, New York, USA
| | - M. Berg
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dubendorf, Switzerland
| | | | - L. Charlet
- LGIT-OSUG, University of Grenoble, Grenoble, France
| | - J. Metral
- LGIT-OSUG, University of Grenoble, Grenoble, France
| | - D. Tisserand
- LGIT-OSUG, University of Grenoble, Grenoble, France
| | - S. Guillot
- LGIT-OSUG, University of Grenoble, Grenoble, France
| | - S. Chakraborty
- Department of Chemistry, Kanchrapara College, Kanchrapara, West Bengal, India
| | - A.P. Gajurel
- Institute of Science and Technology, Tribhuvan University, Kirtipur, Kathmandu, Nepal
| | - B.N. Upreti
- Institute of Science and Technology, Tribhuvan University, Kirtipur, Kathmandu, Nepal
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van Geen A, Radloff K, Aziz Z, Cheng Z, Huq MR, Ahmed KM, Weinman B, Goodbred S, Jung HB, Zheng Y, Berg M, Trang PTK, Charlet L, Metral J, Tisserand D, Guillot S, Chakraborty S, Gajurel AP, Upreti BN. Comparison of arsenic concentrations in simultaneously-collected groundwater and aquifer particles from Bangladesh, India, Vietnam, and Nepal. Appl Geochem 2008. [PMID: 19884967 DOI: 10.1016/j.apgeochem.2008.06.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
One of the reasons the processes resulting in As release to groundwater in southern Asia remain poorly understood is the high degree of spatial variability of physical and chemical properties in shallow aquifers. In an attempt to overcome this difficulty, a simple device that collects groundwater and sediment as a slurry from precisely the same interval was developed in Bangladesh. Recently published results from Bangladesh and India relying on the needle-sampler are augmented here with new data from 37 intervals of grey aquifer material of likely Holocene age in Vietnam and Nepal. A total of 145 samples of filtered groundwater ranging in depth from 3 to 36 m that were analyzed for As (1-1000 mug/L), Fe (0.01-40 mg/L), Mn (0.2-4 mg/L) and S (0.04-14 mg/L) are compared. The P-extractable (0.01-36 mg/kg) and HCl-extractable As (0.04-36 mg/kg) content of the particulate phase was determined in the same suite of samples, in addition to Fe(II)/Fe ratios (0.2-1.0) in the acid-leachable fraction of the particulate phase. Needle-sampler data from Bangladesh indicated a relationship between dissolved As in groundwater and P-extractable As in the particulate phase that was interpreted as an indication of adsorptive equilibrium, under sufficiently reducing conditions, across 3 orders of magnitude in concentrations according to a distribution coefficient of 4 mL/g. The more recent observations from India, Vietnam and Nepal show groundwater As concentrations that are often an order of magnitude lower at a given level of P-extractable As compared to Bangladesh, even if only the subset of particularly reducing intervals characterized by leachable Fe(II)/Fe >0.5 and dissolved Fe >0.2 mg/L are considered. Without attempting to explain why As appears to be particularly mobile in reducing aquifers of Bangladesh compared to the other regions, the consequences of increasing the distribution coefficient for As between the particulate and dissolved phase to 40 mL/g for the flushing of shallow aquifers of their initial As content are explored.
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Affiliation(s)
- A van Geen
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York, USA
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Abstract
It has been an outstanding problem that a semiconducting host in the bulk form can be doped to a large extent, while the same host in the nanocrystal form is found to resist any appreciable level of doping rather stubbornly, this problem being more acute in the wurtzite form compared to the zinc blende one. In contrast, our results based on the lattice parameter tuning in a Zn(x)Cd(1-x)S alloy nanocrystal system achieves approximately 7.5% Mn(2+) doping in a wurtzite nanocrystal, such a concentration being substantially higher compared to earlier reports even for nanocrystal hosts with the "favorable" zinc-blende structure. These results prove a consequence of local strains due to a size mismatch between the dopant and the host that can be avoided by optimizing the composition of the alloyed host. Additionally, the present approach opens up a new route to dope such nanocrystals to a macroscopic extent as required for many applications. Photophysical studies show that the quantum efficiency per Mn(2+) ion decreases exponentially with the average number of Mn(2+) ions per nanocrystal; en route, a high quantum efficiency of approximately 25% is achieved for a range of compositions.
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Affiliation(s)
- Angshuman Nag
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore-560 012, India
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Jha A, Raj Mohan B, Chakraborty S, Meikap BC. Studies on gas holdup in a bubble column using porous spargers with additives. ASIA-PAC J CHEM ENG 2008. [DOI: 10.1002/apj.137] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Moniaux N, Chakraborty S, Yalniz M, Gonzalez J, Shostrom VK, Standop J, Lele SM, Ouellette M, Pour PM, Sasson AR, Brand RE, Hollingsworth MA, Jain M, Batra SK. Early diagnosis of pancreatic cancer: neutrophil gelatinase-associated lipocalin as a marker of pancreatic intraepithelial neoplasia. Br J Cancer 2008; 98:1540-7. [PMID: 18392050 PMCID: PMC2391106 DOI: 10.1038/sj.bjc.6604329] [Citation(s) in RCA: 131] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2008] [Revised: 02/28/2008] [Accepted: 03/04/2008] [Indexed: 12/13/2022] Open
Abstract
Pancreatic cancer is a highly lethal malignancy with a dismal 5-year survival of less than 5%. The scarcity of early biomarkers has considerably hindered our ability to launch preventive measures for this malignancy in a timely manner. Neutrophil gelatinase-associated lipocalin (NGAL), a 24-kDa glycoprotein, was reported to be upregulated nearly 27-fold in pancreatic cancer cells compared to normal ductal cells in a microarray analysis. Given the need for biomarkers in the early diagnosis of pancreatic cancer, we investigated the expression of NGAL in tissues with the objective of examining if NGAL immunostaining could be used to identify foci of pancreatic intraepithelial neoplasia, premalignant lesions preceding invasive cancer. To examine a possible correlation between NGAL expression and the degree of differentiation, we also analysed NGAL levels in pancreatic cancer cell lines with varying grades of differentiation. Although NGAL expression was strongly upregulated in pancreatic cancer, and moderately in pancreatitis, only a weak expression could be detected in the healthy pancreas. The average composite score for adenocarcinoma (4.26+/-2.44) was significantly higher than that for the normal pancreas (1.0) or pancreatitis (1.0) (P<0.0001). Further, although both well- and moderately differentiated pancreatic cancer were positive for NGAL, poorly differentiated adenocarcinoma was uniformly negative. Importantly, NGAL expression was detected as early as the PanIN-1 stage, suggesting that it could be a marker of the earliest premalignant changes in the pancreas. Further, we examined NGAL levels in serum samples. Serum NGAL levels were above the cutoff for healthy individuals in 94% of pancreatic cancer and 62.5% each of acute and chronic pancreatitis samples. However, the difference between NGAL levels in pancreatitis and pancreatic cancer was not significant. A ROC curve analysis revealed that ELISA for NGAL is fairly accurate in distinguishing pancreatic cancer from non-cancer cases (area under curve=0.75). In conclusion, NGAL is highly expressed in early dysplastic lesions in the pancreas, suggesting a possible role as an early diagnostic marker for pancreatic cancer. Further, serum NGAL measurement could be investigated as a possible biomarker in pancreatitis and pancreatic adenocarcinoma.
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MESH Headings
- Acute-Phase Proteins/analysis
- Acute-Phase Proteins/genetics
- Adenocarcinoma/blood
- Adenocarcinoma/chemistry
- Adenocarcinoma/diagnosis
- Adult
- Aged
- Biomarkers, Tumor/analysis
- Biomarkers, Tumor/blood
- Biomarkers, Tumor/genetics
- Blotting, Western
- Carcinoma, Pancreatic Ductal/blood
- Carcinoma, Pancreatic Ductal/chemistry
- Carcinoma, Pancreatic Ductal/diagnosis
- Cell Line, Tumor
- Early Diagnosis
- Enzyme-Linked Immunosorbent Assay
- Female
- Gene Expression Regulation, Neoplastic
- Humans
- Immunohistochemistry
- Lipocalin-2
- Lipocalins/analysis
- Lipocalins/blood
- Lipocalins/genetics
- Male
- Middle Aged
- Pancreatic Neoplasms/blood
- Pancreatic Neoplasms/chemistry
- Pancreatic Neoplasms/diagnosis
- Proto-Oncogene Proteins/analysis
- Proto-Oncogene Proteins/blood
- Proto-Oncogene Proteins/genetics
- RNA, Neoplasm/analysis
- ROC Curve
- Reverse Transcriptase Polymerase Chain Reaction
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Affiliation(s)
- N Moniaux
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - S Chakraborty
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - M Yalniz
- Eppley Institute for Cancer Research, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - J Gonzalez
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - V K Shostrom
- Department of Societal and Preventive Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - J Standop
- Eppley Institute for Cancer Research, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - S M Lele
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - M Ouellette
- Eppley Institute for Cancer Research, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - P M Pour
- Eppley Institute for Cancer Research, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - A R Sasson
- Department of Surgery, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - R E Brand
- Division of Gastroenterology, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA
| | - M A Hollingsworth
- Eppley Institute for Cancer Research, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - M Jain
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - S K Batra
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Eppley Institute for Cancer Research, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198, USA
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Cohen JA, Calabresi PA, Chakraborty S, Edwards KR, Eickenhorst T, Felton WL, Fisher E, Fox RJ, Goodman AD, Hara-Cleaver C, Hutton GJ, Imrey PB, Ivancic DM, Mandell BF, Perryman JE, Scott TF, Skaramagas TT, Zhang H. Avonex Combination Trial in relapsing—remitting MS: rationale, design and baseline data. Mult Scler 2008; 14:370-82. [DOI: 10.1177/1352458507083189] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective To review the rationale, design and baseline data of the Avonex Combination Trial (ACT), an investigator-run study of intramuscular interferon beta-1a (IM IFNβ-1a) combined with methotrexate (MTX) and/or IV methylprednisolone (IVMP) in relapsing—remitting multiple sclerosis (RRMS) patients with continued disease activity on IM IFNβ-1a monotherapy. Methods Eligibility criteria included RRMS, Expanded Disability Status Scale score 0—5.5, and ≥1 relapse or gadolinium-enhancing MRI lesion in the prior year while on IM IFNβ-1a monotherapy. Subjects continued IFNβ-1a 30 mcg IM weekly and were randomized in a 2 × 2 factorial design to adjunctive weekly placebo or MTX 20 mg PO, with or without IVMP 1000 mg/day for three days every other month. ACT was industry-supported, and collaboratively designed and governed by an Investigator Steering Committee with independent Advisory and Data Safety Monitoring Committees. Study operations, MRI analysis and aggregated data were managed by the Cleveland Clinic MS Academic Coordinating Center. Results In total 313 subjects were enrolled with clinical and MRI characteristics typical of RRMS. Most subjects (86.9%) qualified with a clinical relapse, with or without an enhancing MRI lesion, in the preceding year. At baseline, 21.4% had enhancing lesions, and 5.1% had anti-IFNβ neutralizing antibodies. ACT's management and operational structures functioned well. Conclusion This study provides an innovative model for academic—industry collaborative MS research and will enhance understanding of the utility of combination therapy for RRMS patients with continued disease activity on an established first-line treatment. Multiple Sclerosis 2008; 14: 370—382. http://msj.sagepub.com
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Affiliation(s)
- JA Cohen
- Mellen Center, Cleveland Clinic Foundation, Cleveland, OH 44195, USA,
| | - PA Calabresi
- Department of Neurology, Johns Hopkins, Baltimore, MD 21287, USA
| | - S. Chakraborty
- Quantitative Health Sciences, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
| | - KR Edwards
- MS Center of Southern Vermont, Bennington, VT 05201, USA
| | - T. Eickenhorst
- Medical Affairs, Biogen Idec, Inc., Cambridge, MA 02142, USA
| | - WL Felton
- Department of Neurology, Virginia Commonwealth University Medical Center, Richmond, VA 23298, USA
| | - E. Fisher
- Biomedical Engineering, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
| | - RJ Fox
- Mellen Center, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
| | - AD Goodman
- Department of Neurology, University of Rochester, Rochester, NY 14642, USA
| | - C. Hara-Cleaver
- Mellen Center, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
| | - GJ Hutton
- Department of Neurology, Baylor College of Medicine, Houston, TX 77030, USA
| | - PB Imrey
- Quantitative Health Sciences, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
| | - DM Ivancic
- Mellen Center, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
| | - BF Mandell
- Department of Rheumatic and Immunologic Disease, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
| | - JE Perryman
- Mellen Center, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
| | - TF Scott
- Drexel College of Medicine, Pittsburgh, PA 15212, USA
| | - TT Skaramagas
- Mellen Center, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
| | - H. Zhang
- Medical Affairs, Biogen Idec, Inc., Cambridge, MA 02142, USA
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239
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Das S, Chakraborty S, Parkash O, Kumar D, Bandyopadhyay S, Samudrala S, Sen A, Maiti H. Vanadium doped tin dioxide as a novel sulfur dioxide sensor. Talanta 2008; 75:385-9. [DOI: 10.1016/j.talanta.2007.11.010] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2007] [Revised: 11/07/2007] [Accepted: 11/07/2007] [Indexed: 11/30/2022]
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Chakraborty S, Vanitharani R, Chattopadhyay B, Fauquet CM. Supervirulent pseudorecombination and asymmetric synergism between genomic components of two distinct species of begomovirus associated with severe tomato leaf curl disease in India. J Gen Virol 2008; 89:818-828. [PMID: 18272774 DOI: 10.1099/vir.0.82873-0] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023] Open
Abstract
Isolates of two distinct begomovirus species, the severe strain of the species Tomato leaf curl New Delhi virus (tomato leaf curl New Delhi virus-[India:New Delhi:Severe:1992]; ToLCNDV-[IN:ND:Svr:92], bipartite) and the Varanasi strain of the species Tomato leaf curl Gujarat virus (tomato leaf curl Gujarat virus-[India:Varanasi:2001]; ToLCGV-[IN:Var:01], mono/bipartite) infect tomato (Lycopersicon esculentum) and cause severe yield losses in northern India. This study investigated the infectivity properties of genomic components of these two species. Both pseudorecombinants were infectious in Nicotiana benthamiana, Nicotiana tabacum and L. esculentum. Enhanced pathogenicity was observed when DNA-A of ToLCNDV-[IN:ND:Svr:92] was trans-complemented with ToLCGV-[IN:Var:01] DNA-B, and was consistently associated with an increase in accumulation of ToLCGV-[IN:Var:01] DNA-B. Mixed infection of ToLCNDV-[IN:ND:Svr:92] and ToLCGV-[IN:Var:01] always showed extremely severe symptoms, suggesting a synergistic interaction between these two viruses. Southern blot analysis of viral DNAs from infected plants showed a significantly higher level of accumulation of both ToLCNDV components and DNA-B of ToLCGV-[IN:Var:01] with no alteration to levels of DNA-A of ToLCGV-[IN:Var:01]. Symptom development and/or higher infectivity of the supervirulent pseudorecombinants correlated with the increased levels of DNA-B accumulation. Protoplast replication assays revealed that enhanced infectivity by the pseudorecombinant occurred at the level of replication, as DNA-A of ToLCNDV-[IN:ND:Svr:92] enhanced ToLCGV-[IN:Var:01] DNA-B replication, whose accumulation was in turn increased by ToLCGV-[IN:Var:01] DNA-A. This is the first report demonstrating a virulent pseudorecombinant between two distinct species of begomoviruses that infect tomato, and is the second report on synergism between begomoviruses. The results revealed that ToLCGV-[IN:Var:01] DNA-B is capable of associating with different DNA-A components, despite having different iteron sequences.
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Affiliation(s)
- S Chakraborty
- International Laboratory for Tropical Agricultural Biotechnology, Donald Danforth Plant Science Center, 975 N. Warson Road, St Louis, MO 63132, USA
| | - R Vanitharani
- International Laboratory for Tropical Agricultural Biotechnology, Donald Danforth Plant Science Center, 975 N. Warson Road, St Louis, MO 63132, USA
| | - B Chattopadhyay
- International Laboratory for Tropical Agricultural Biotechnology, Donald Danforth Plant Science Center, 975 N. Warson Road, St Louis, MO 63132, USA
| | - C M Fauquet
- International Laboratory for Tropical Agricultural Biotechnology, Donald Danforth Plant Science Center, 975 N. Warson Road, St Louis, MO 63132, USA
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241
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Shukla D, Chakraborty S, Rajendran A. Combined pharmacotherapy and thermotherapy for chronic central serous chorioretinopathy with anterior segment neovascularisation. Eye (Lond) 2008; 22:600-2. [PMID: 18219334 DOI: 10.1038/sj.eye.6703106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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242
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Aviv RI, Mandelcorn J, Chakraborty S, Gladstone D, Malham S, Tomlinson G, Fox AJ, Symons S. Alberta Stroke Program Early CT Scoring of CT perfusion in early stroke visualization and assessment. AJNR Am J Neuroradiol 2007; 28:1975-80. [PMID: 17921237 DOI: 10.3174/ajnr.a0689] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Qualitative CT perfusion (CTP) assessment by using the Alberta Stroke Program Early CT Score (ASPECTS) allows rapid calculation of infarct extent for middle cerebral artery infarcts. Published thresholds exist for noncontrast CT (NCCT) ASPECTS, which may distinguish outcome/complication risk, but early ischemic signs are difficult to detect. We hypothesized that different ASPECTS thresholds exist for CTP parameters versus NCCT and that these may be superior at predicting clinical and radiologic outcome in the acute setting. MATERIALS AND METHODS Thirty-six baseline acute stroke NCCT and CTP studies within 3 hours of symptoms were blindly reviewed by 3 neuroradiologists, and ASPECTS were assigned. Treatment response was defined as major neurologic improvement when a > or =8-point National Institutes of Health Stroke Scale improvement at 24 hours occurred. Follow-up NCCT ASPECTS and 90-day modified Rankin score (mRS) were radiologic and clinical reference standards. Receiver operating characteristic curves derived optimal thresholds for outcome. RESULTS Cerebral blood volume and NCCT ASPECTS had similar radiologic correlations (0.6 and 0.5, respectively) and best predicted infarct size in the absence of major neurologic improvement. A NCCT ASPECT threshold of 7 and a cerebral blood volume threshold of 8 discriminated patients with poor follow-up scans (P < .0002 and P = .0001) and mRS < or =2 (P = .001 and P < .001). Only cerebral blood volume predicted major neurologic improvement (P = .02). Interobserver agreement was substantial (intraclass correlation coefficient, 0.69). Cerebral blood volume ASPECTS sensitivity, specificity, positive predictive value, and negative predictive value for clinical outcome were 60%, 100%, 100%, and 45%, respectively. No patients with cerebral blood volume ASPECTS <8 achieved good clinical outcome. CONCLUSION Cerebral blood volume ASPECTS is equivalent to NCCT for predicting radiologic outcome but may have an additional benefit in predicting patients with major neurologic improvement.
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Affiliation(s)
- R I Aviv
- Division of Neuroradiology, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada.
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243
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Chakraborty S, Misra P, Wategaonkar S. Zero kinetic energy spectroscopy of hydroquinone-water (1:1) complex: A probe for conformer assignment. J Chem Phys 2007; 127:124317. [PMID: 17902913 DOI: 10.1063/1.2780158] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Zero kinetic energy (ZEKE) photoelectron spectroscopy of the hydroquinone-water (HQW) complex was carried out to characterize its S(1)-S(0) resonantly enhanced multiphoton ionization (REMPI) spectrum in terms of the cis and trans conformers. The ZEKE spectra of the hydroquinone isomers show differences in the Franck-Condon (FC) activity of a few ring modes, viz., modes 15, 9b, and 6b, due to the different symmetries of the two isomers. These modes were used as a "diagnostic tool" to carry out the categorical assignment of the REMPI spectrum of the HQW complex. It was found that the FC activity of these diagnostic modes in the cationic ground state (D(0)) of the water complex is similar as that of the monomer. The two lowest energy transitions in the REMPI spectrum of the water complex, 33,175 and 33,209 cm(-1), were reassigned as the band origins of the cis and trans hydroquinone-water complexes, which is opposite of the previous assignment. The intermolecular stretching mode (sigma) of the complex shows a long progression, up to v(')=4, in the cationic ground state and is strongly coupled to other observed ring modes. The Franck-Condon factors for different members in the progression were calculated using the potential energy surfaces computed ab initio. These agree well with the observed intensity patterns in the progression. The ionization potential of the trans and cis complexes was determined to be 60,071+/-4 and 60,024+/-4 cm(-1), respectively.
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Affiliation(s)
- S Chakraborty
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai-400005, India
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Abstract
We present a case of liposarcoma in a 37-year-old female with a chronic history of nasal stuffiness. MR imaging revealed a fatty lesion in the nasopharynx. Subsequent tissue sampling and histopathology demonstrated features consistent with a liposarcoma.
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Affiliation(s)
- S Chakraborty
- Princess Margaret Hospital, University Health Network, 610 University Avenue, Toronto, Ontario, Canada M5G 2M9
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Singh AK, Chattopadhyay B, Pandey PK, Singh AK, Chakraborty S. A New Begomovirus Species Causing Leaf Curl Disease of Radish in India. Plant Dis 2007; 91:1053. [PMID: 30780448 DOI: 10.1094/pdis-91-8-1053b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Leaf curl disease of radish (RLCD) was observed for the first time in India in commercial fields and kitchen gardens of the Varanasi District and adjoining areas of eastern Uttar Pradesh during November 2003. Infected plants exhibited typical upward and downward leaf curling, leaf distortion, reduction of leaf area, and conspicuous enations on the underside of the leaves. Incidence of RLCD was estimated to be between 10 and 40% depending on the cultivars used. Electron microscopic observation revealed typical geminate particles in infected leaf samples. The causal virus could be transmitted to radish cv. Minu Early by whiteflies (Bemisia tabaci) and grafting. Inoculated plants developed symptoms similar to those observed in naturally infected radish plants. Viral DNA was isolated from artificially inoculated symptomatic radish plants (4) followed by concentration of super-coiled DNA by alkaline denaturation (1). The presence of a geminivirus was confirmed by PCR using DNA-A degenerate primers (3), and a 1.5-kb amplified product was obtained from six artificially and three naturally infected plants. Amplification of the full-length DNA-A was achieved using a primer combination derived from sequences obtained from a 1.5-kb amplicon. Amplification of 1.3-kb DNA-β sequences was achieved using specific primers (2) in three infected plants. Sequence analysis revealed that DNA-A (GenBank Accession No. EF 175733) contained 2,756 nt and DNA-β contained 1,358 nt (GenBank Accession No. EF 175734). DNA-A of the causal virus shares 87.7% identity with Tomato leaf curl Bangladesh virus (GenBank Accession No. AF 188481) and 62% identity with Mungbean yellow mosaic India virus (GenBank Accession No. AF126406). The begomovirus DNA-A sequence associated with RLCD contained seven open reading frames (AV1, AV2, AC1, AC2, AC3, AC4, and AC5). The DNA-β associated with RLCD shared the highest nucleotide sequence identity (84.9%) with DNA-β of Tobacco leaf curl virus isolate NIB 12-1 (GenBank Accession No. AJ316033) reported from Pakistan. Despite exhaustive attempts to amplify a putative viral B-component using degenerate primers based on the intergenic region sequence of the DNA-A or sequences that are highly conserved for other begomoviruses, no DNA-B component was detected. On the basis of DNA-A sequence analysis, the ICTV species demarcation criteria of 89% sequence identity, and genome organization, the virus causing RLCD should be considered a new Begomovirus species, for which the name Radish leaf curl virus (RLCV) is proposed. To our knowledge, this is the first report of the association of a Begomovirus with a disease of radishes in India. References: (1) H. C. Birnboim and J. Doly. Nucleic Acids Res. 7:1513, 1979. (2) R. W. Briddon et al. Mol. Biotechnol. 20:315, 2002. (3) M. R. Rojas et al. Plant Dis. 77:340, 1993. (4) K. M. Srivastava et al. J. Virol. Methods 51:297, 1995.
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Affiliation(s)
- A K Singh
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi -110 067, India and Indian Institute of Vegetable Research, Varanasi, Uttar Pradesh, India
| | - B Chattopadhyay
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi -110 067, India
| | - P K Pandey
- Indian Institute of Vegetable Research, Varanasi, Uttar Pradesh, India
| | - A K Singh
- Botany Department, U.P. Autonomous College, Varanasi, Uttar Pradesh, India
| | - S Chakraborty
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi -110 067, India
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Nag A, Sapra S, Chakraborty S, Basu S, Sarma DD. Synthesis of CdSe nanocrystals in a noncoordinating solvent: effect of reaction temperature on size and optical properties. J Nanosci Nanotechnol 2007; 7:1965-8. [PMID: 17654973 DOI: 10.1166/jnn.2007.749] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Colloidal synthesis of high quality CdSe nanocrystals with controllable size and tunable properties have been one of the most important topics of research over the last decade, in view of its huge technological potentials. CdSe is one of the most studied nanocrystals of this category because of its photoluminescence tunability across the visible spectrum. We have synthesized CdSe nanocrystals using CdO precursor in a noncoordinating solvent and studied the effect of the reaction temperature on the size and optical properties of the nanocrystals. The size of the nanocrystals could be varied systematically in the range of 3.5 to 6.6 nm diameter with a remarkably narrow size distribution by controlling only the reaction temperature, without any need for a post-synthesis processing. The band gap and the corresponding band edge emission could be tuned across the entire visible range by tuning the size of the nanocrystals. The narrow width of the photoluminescence emissions of different colours (blue to red) make these nanocrystals a potential candidate for different optical and optoelectronic devices.
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Affiliation(s)
- Angshuman Nag
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
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247
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Aviv R, Shelef I, Malam S, Chakraborty S, Sahlas D, Tomlinson G, Symons S, Fox A. Early stroke detection and extent: impact of experience and the role of computed tomography angiography source images. Clin Radiol 2007; 62:447-52. [DOI: 10.1016/j.crad.2006.11.019] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2006] [Revised: 11/03/2006] [Accepted: 11/08/2006] [Indexed: 10/23/2022]
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Chatterjee M, Silva Filho EV, Sarkar SK, Sella SM, Bhattacharya A, Satpathy KK, Prasad MVR, Chakraborty S, Bhattacharya BD. Distribution and possible source of trace elements in the sediment cores of a tropical macrotidal estuary and their ecotoxicological significance. Environ Int 2007; 33:346-56. [PMID: 17196656 DOI: 10.1016/j.envint.2006.11.013] [Citation(s) in RCA: 128] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2006] [Revised: 11/07/2006] [Accepted: 11/13/2006] [Indexed: 05/13/2023]
Abstract
The paper presents the first document regarding concentration, distribution and possible sources of selected trace elements (Cu, Fe, Mn, Zn, Cr, Co, Ni, Pb, Al, B and Ba) in core sediments (<63 micro particle size) from the lower stretch of Hugli (Ganges) estuary, northeast coast of Bay of Bengal by ICP-AES and EDXRF to evaluate geochemical processes influencing their distribution and possible environmental consequences. The levels of elements showed a wide range of variations in different core depths, in upper and lower intertidal zones as well as among three sampling stations. The most interesting feature of the study is the downward increase of concentrations of majority of the elements reaching overall maximum values at a depth of 20-28 cm in upper littoral zone of the site located in the extreme downstream stretch of the estuary. Values of organic carbon showed very strong positive correlations with most of the elements as revealed by correlation matrix (r) values. The interelemental relationship revealed the identical behavior of element during its transport in the estuarine environment. The overall variation in concentration can be attributed to differential discharge of untreated effluents originating from industrial, agricultural, and aquacultural sources as well as from domestic sewage along with the fishing and boating activities. The resulting compositional dataset was tested by principal component analyses and cluster analyses. Pollution load index (PLI) and index of Geoaccumulation (Igeo) revealed overall low values but the enrichment factors (EFs) for Pb were typically high for all the stations. The mean concentrations of Zn and to some extent Cu exceeded the Effects Range-Low (ER-L) values in the majority of the cases indicating that there may be some ecotoxicological risk to organisms living in sediments. The concentration of the trace elements reported in this work is useful as baselines for comparison in future sediment quality studies.
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Affiliation(s)
- M Chatterjee
- Department of Marine Science, University of Calcutta, 35 Ballygunge Circular Road, Calcutta 700019, India
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249
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Chakraborty S, Das T, Banerjee S, Sarma HD, Venkatesh M. Preparation and preliminary biological evaluation of a novel 109Pd labeled porphyrin derivative for possible use in targeted tumor therapy. Q J Nucl Med Mol Imaging 2007; 51:16-23. [PMID: 17372569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
AIM The labeling of a porphyrin, a tumor-avid agent, with a beta-emitting radionuclide for evaluating its potential as an agent for targeted tumor therapy is reported. A novel water soluble porphyrin viz. 5,10,15,20-tetrakis[3,4-bis(carboxymethyleneoxy)phenyl]porphyrin radiolabeled with(109)Pd (E(beta(max))=1.12 MeV, Eg=88 keV (3.6%), T1/2=13.7 h) has been prepared. The designing of this agent is based on the speculation that (109)Pd would complex with the tetrapyrrole donor array constituting the porphyrin core, resulting in a species with peripheral hydrophilic residues for facilitating renal excretion. METHODS Palladium-109 was produced by thermal neutron bombardment on enriched metallic Pd target at a flux of 3 x 10(13) n/cm(2) x s for 3 days and the porphyrin derivative was synthesized by a multi-step reaction using 3,4 dihydroxybenzaldehyde and pyrrole. The labeling parameters were optimized for obtaining maximum complexation yield and the biological behavior of the radiolabeled porphyrin was studied in Swiss mice bearing fibrosarcoma tumors. RESULTS Palladium-109 was produced with a specific activity of approximately 1.85 GBq/mg and approximately 100% radionuclidic purity. Lead-109 complex of the synthesized porphyrin derivative was prepared with excellent radiochemical purity (approximately 98%) and the complex was observed to be stable upto 24 h at room temperature. Results of the biodistribution studies revealed good tumor uptake (2.8+/-0.57%/g) within 30 min post-injection and it remained almost constant till 24 h post-injection. The complex showed predominantly renal clearance (88.68+/-4.01% at 24 h post-injection). CONCLUSIONS The high tumor/blood and tumor/muscle ratios (4.36 and 38 at 24 h post-injection) exhibited by the radiolabeled porphyrin indicate its potential for using in targeted tumor therapy.
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Affiliation(s)
- S Chakraborty
- Radiopharmaceuticals Division, Bhabha Atomic Research Center, Mumbai, India
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Ali M, Chattopadhyay S, Nag A, Kumar A, Sapra S, Chakraborty S, Sarma DD. White-light emission from a blend of CdSeS nanocrystals of different Se:S ratio. Nanotechnology 2007; 18:075401. [PMID: 21730500 DOI: 10.1088/0957-4484/18/7/075401] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
CdSeS nanocrystals with different bandgap energies have been synthesized by the colloidal method. The solution blend of blue-, green- and red-emitting CdSeS nanocrystals, in appropriate proportions, showed strong white emission of different shades on excitation with a UV source. We observed that the CIE coordinate of the spectrum of a particular blend is independent of excitation wavelength. We also observed that the contribution of self-absorption in energy loss in the blend of CdSeS nanocrystals is not very significant. A white-light-emitting LED has been fabricated by coating a blend mixed with polymethylmethacrylate on a commercial UV-LED.
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Affiliation(s)
- Moazzam Ali
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
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