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Aravamudhan R, Sampath V, Kannan R, Kumar P, Srinivasan V, Sridevi MM. Interleukin-17 Inhibitor in Treatment of Psoriasis during COVID-19 Pandemic: An Ambispective Study. J Clin Diagn Res 2023. [DOI: 10.7860/jcdr/2023/59172.17381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Introduction: Psoriasis is a genetically mediated chronic inflammatory disease that is frequently associated with metabolic co-morbidities. These metabolic co-morbidities have a huge impact in deciding the appropriate immunosupressant of choice in the current scenario of Coronavirus Disease (COVID19) pandemic. Treatment of psoriasis especially with biologicals is challenging during covid pandemic since immunosuppressive therapy might interfere with antiviral immunity. Aim: To report the safety profile of Interleukin-17 (IL-17) inhibitor, namely injection secukinumab in patients of psoriasis vulgaris during COVID-19 pandemic. Materials and Methods: An ambispective interventional study was performed on 23 patients of psoriasis who were administered secukinumab at a dose of 300 mg subcutaneously during COVID19 pandemic.The study was conducted at the Department of Dermatology, Madras Medical College, Chennai, Tamil Nadu, India among the patients attending the psoriasis clinic between the July 2021 to March 2022. The demographic characteristics of the study group, previous treatment for psoriasis and the relationship between risk of COVID-19 infection and secukinumab were noted. Efficacy of secukinumab was calculated using Psoriasis Area and Severity Index (PASI) scores. Statistical analysis was conducted with Statistical Package for Social Sciences (SPSS) statistics software version 21.0 by Fischer’s-exact test. Results: Out of 23 patients, 17 patients (11 males, six females) completed full course of nine doses (five weekly doses followed by four monthly doses) of secukinumab. The PASI 75 and PASI 90 were achieved in 9 (52.94%) and 8 (29.41%) patients respectively at the end of 12 weeks. None of the patients developed COVID-19 infection during the course of treatment and three months following therapy. Patients with psoriasis who had a history of COVID-19 infection did not show signs of reinfection when started on secukinumab. Both inactivated vaccine (Covaxin) and vector based vaccine (Covishield) were found to be safe in concomitant use with secukinumab. Conclusion: Secukinumab is found to be safe and effective in psoriasis treatment during COVID-19 pandemic. There is no increased risk of COVID-19 infection or reinfection, COVID-19 associated hospitalisation and mortality among patients with psoriasis administered with secukinumab. The drug can also be safely used with COVID-19 vaccines.
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Sampath V, Park JH, Ha BD, Han K, Kim IH. Evaluation of Lactobacillus Plantarum Additive on Growth Performance, Excreta Microbiota, Nutrient Digestibility, Gas Emission, and Meat Quality in Ross308-Broilers. Braz J Poult Sci 2022. [DOI: 10.1590/1806-9061-2021-1551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- V Sampath
- Dankook University, Republic of Korea
| | - JH Park
- Microsolution Co., Ltd, Republic of Korea
| | - BD Ha
- Microsolution Co., Ltd, Republic of Korea
| | - K Han
- Dankook University, Republic of Korea; Dankook University, Republic of Korea
| | - IH Kim
- Dankook University, Republic of Korea
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Ramesh A, Sampath V, Kannan R, Daniel SJ, Kumar LBA, Deepavarshini P. Lobular Capillary Haemangioma Occurring Over Port-Wine Stain in a Patient of Sturge-Weber Syndrome: A Case Report. Indian J Dermatol 2022; 67:481. [PMID: 36578767 PMCID: PMC9792022 DOI: 10.4103/ijd.ijd_78_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- A. Ramesh
- From the Department of DVL, Madras Medical College, Chennai, Tamil Nadu, India E-mail:
| | - V. Sampath
- From the Department of DVL, Madras Medical College, Chennai, Tamil Nadu, India E-mail:
| | - Rajkumar Kannan
- From the Department of DVL, Madras Medical College, Chennai, Tamil Nadu, India E-mail:
| | - Samuel J. Daniel
- From the Department of DVL, Madras Medical College, Chennai, Tamil Nadu, India E-mail:
| | - L. B. Ajith Kumar
- From the Department of DVL, Madras Medical College, Chennai, Tamil Nadu, India E-mail:
| | - P. Deepavarshini
- From the Department of DVL, Madras Medical College, Chennai, Tamil Nadu, India E-mail:
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Balu SK, Sampath V, Andra S, Alagar S, Manisha Vidyavathy S. Fabrication of carbon and silver nanomaterials incorporated hydroxyapatite nanocomposites: Enhanced biological and mechanical performances for biomedical applications. Mater Sci Eng C Mater Biol Appl 2021; 128:112296. [PMID: 34474847 DOI: 10.1016/j.msec.2021.112296] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 06/14/2021] [Accepted: 06/30/2021] [Indexed: 10/20/2022]
Abstract
Hydroxyapatite is widely utilized for different biomedical applications because of its outstanding biocompatibility and bioactivity. Cuttlefish bones, which are available aplenty, are both inexpensive and eco-friendly sources for calcium carbonate. In the present study, cuttlefish bones-derived HAp nanorods have been utilized to fabricate HAp nanocomposites incorporating 1, 3 and 5 wt% each of GO, MWCNTs, GONRs and Ag NPs. Characterization using such techniques as XRD, FTIR, HRSEM and EDS was performed to analyze the physicochemical properties of nanocomposites, and MTT assay, hemolysis, bioactivity and drug release to evaluate the biological properties. The XRD and HRSEM results reveal that crystallite and particle size increase with increasing wt% of carbon nanomaterials and Ag NPs. However, the addition of nanomaterials did not modify the shape of HAp. The MTT assay and hemolysis results suggest GONRs possess better biocompatibility than GO and CNTs due to their smooth edge structure. While adding carbon materials up to 3 wt% caused an increase in the hardness, adding up to 5 wt% of them caused a decrease in the hardness due to the agglomeration of the particles. Biocompatibility and Vicker's hardness studies show that adding carbon nanomaterials up to 3 wt% caused significant improvement in biocompatibility and mechanical properties. Antibacterial activity test was performed to analyze the ability to preclude the formation of biofilms. The results showed better activity for silver-incorporated nanocomposites in the presence of E. coli and S. aureus bacteria. Drug release studies were performed using lidocaine drug and the results showed nearly similar drug release profile for all the samples except HAg3. Finally, nanocomposite HRA3 could be a suitable candidate for biomedical applications since it shows better biological and mechanical properties than GO and MWCNTs nanocomposites.
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Affiliation(s)
- Satheesh Kumar Balu
- Department of Ceramic Technology, Anna University, Chennai, Tamil Nadu 600025, India
| | - V Sampath
- Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai, Tamil Nadu 600036, India
| | - Swetha Andra
- Center for Nanoscience and Technology, Chennai Institute of Technology, Chennai, Tamil Nadu 600069, India
| | - Srinivasan Alagar
- Institute of Nanoscience and Technology, Sector-81, Knowledge City, Sahibzada Ajit Singh Nagar, Punjab 140306, India
| | - S Manisha Vidyavathy
- Department of Ceramic Technology, Anna University, Chennai, Tamil Nadu 600025, India.
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Kavitha R, Nirmala S, Sampath V, Shanmugavalli V, Latha B. Studies of synthesis, crystal structure and antidiabetic activity of quinolinium 2-carboxylate 2-chloroacetic acid. J Mol Struct 2021. [DOI: 10.1016/j.molstruc.2021.130572] [Citation(s) in RCA: 1] [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: 01/04/2023]
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Balu SK, Andra S, Jeevanandam J, S MV, V S. Emerging marine derived nanohydroxyapatite and their composites for implant and biomedical applications. J Mech Behav Biomed Mater 2021; 119:104523. [PMID: 33940538 DOI: 10.1016/j.jmbbm.2021.104523] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 03/29/2021] [Accepted: 04/05/2021] [Indexed: 01/30/2023]
Abstract
Implant materials must mimic natural human bones with biocompatibility, osteoconductivity and mechanical stability to successfully replace damaged or disease-affected bones. Synthetic hydroxyapatite was incorporated with bioglass to mimic natural bones for replacing conventional implant materials which has led to certain toxicity issues. Hence, hydroxyapatite (HAp) are recently gaining applicational importance as they are resembling the structure and function of natural bones. Further, nanosized HAp is under extensive research to utilize them as a potential replacement for traditional implants with several exclusive properties. However, chemical synthesis of nano-HAp exhibited toxicity towards normal and healthy cells. Recently, biogenic Hap synthesis from marine and animal sources are introduced as a next generation implant materials, due to their mineral ion and significant porous architecture mediated biocompatibility and bone bonding ability, compared to synthetic HAp. Thus, the purpose of the paper is to give a bird's eye view into the conventional approaches for fabricating nano-HAp, its limitations and the significance of using marine organisms and marine food wastes as a precursor for biogenic nano-Hap production. Moreover, in vivo and in vitro analyses of marine source derived nano-HAp and their potential biomedical applications were also discussed.
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Affiliation(s)
- Satheesh Kumar Balu
- Department of Ceramic Technology, Anna University, Chennai, Tamil Nadu, 600025, India
| | - Swetha Andra
- Center for Nanoscience and Technology, Chennai Institute of Technology, Chennai, Tamil Nadu, 600069, India
| | - Jaison Jeevanandam
- CQM-Centro de Quimica da Madeira, MMRG, Universidade da Madeira, Campus da Penteada, 9020-105, Funchal, Portugal
| | - Manisha Vidyavathy S
- Department of Ceramic Technology, Anna University, Chennai, Tamil Nadu, 600025, India.
| | - Sampath V
- Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai, Tamil Nadu, 600036, India
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Kumar N, Rocha FG, Moustafa ASZ, Masten M, Bruder A, Parmar K, Adekola H, Sampath V, Monga R. Impact of opioid maintenance treatment during pregnancy on neonatal birth weight and head circumference. J Neonatal Perinatal Med 2021; 14:475-484. [PMID: 33843703 DOI: 10.3233/npm-200645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Pregnant mothers with opioid dependency commonly receive maintenance treatment of opioid (OMT), either as buprenorphine (BMT) or methadone maintenance treatment (MMT). We investigated, whether OMT adversely affects standardized neonatal anthropometric outcomes and whether BMT is potentially safer than MMT in this regard. METHODS Retrospective chart review of mother infant dyad, with and without OMT. Infant's absolute and standardized (z-score) anthropometric outcomes at birth were first compared, between OMT and control group (negative meconium drug screen), and then between BMT and MMT group. These outcomes were also compared between infants who did or did not require treatment after birth for neonatal abstinence syndrome (NAS). RESULT A total of 1479 participants with MDS were included [Control = 1251; OMT = 228 (MMT = 181; BMT = 47)]. Both the z-scores of birth weight (BW) and head circumference (HC) was lower in OMT group (p < 0.001). Among the OMT group, GA at delivery was slightly higher in the BMT group (p = 0.05). There was an inverse correlation between maternal dose at the time of delivery and anthropometric z-scores in the BMT group, mainly in female infants (BW: p = 0.006; HC: p = 0.003). Furthermore, In BMT group, infants with lower HC were more likely to require treatment for NAS (p = 0.01). CONCLUSION HC and BW when comparing Z-scores were not different between MMT and BMT. High maternal dosing of buprenorphine is associated with lower BW and HC Z-scores but dose effect is not seen with methadone. In addition, there seems to be an association between NAS severity and HC, especially in the BMT group.
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Affiliation(s)
- N Kumar
- Division of Neonatology, Hurley Medical Center, Flint, MI, USA
| | - F G Rocha
- Division of Maternal-Fetal Medicine, University of California, San Francisco, CA, USA
| | - A S Z Moustafa
- Department of Obstetrics and Gynecology, Hurley Medical Center, Flint, MI, USA
| | - M Masten
- Department of Obstetrics and Gynecology, Hurley Medical Center, Flint, MI, USA
| | - A Bruder
- Department of Pediatrics, Hurley Medical Center, Flint, MI, USA
| | - K Parmar
- Department of Pediatrics, Hurley Medical Center, Flint, MI, USA
| | - H Adekola
- Division of Maternal-Fetal Medicine, Southern Illinois University, Springfield, IL, USA
| | - V Sampath
- Division of Neonatology, Children's Mercy Hospital, Kansas City, MO, USA
| | - R Monga
- Division of Neonatology, Hurley Medical Center, Flint, MI, USA
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Sampath V, Koo DH, Lim CB, Kim IH. Supplemental Effect of Lactobacillus Plantarum on the Growth Performance, Nutrient Digestibility, Gas Emission, Excreta Microbiota, and Meat Quality in Broilers. Braz J Poult Sci 2021. [DOI: 10.1590/1806-9061-2021-1514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
| | - DH Koo
- Dankook University, South Korea
| | - CB Lim
- Dankook University, South Korea
| | - IH Kim
- Dankook University, South Korea
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Sivasankri P, Ramesh A, Sampath V. Hypereosinophilic syndrome masquerading as acrodermatitis enteropathica. Indian J Dermatol Venereol Leprol 2019; 85:418-422. [PMID: 31172983 DOI: 10.4103/ijdvl.ijdvl_607_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- P Sivasankri
- Department of Dermatology Venereology and Leprosy, Rajiv Gandhi Government General Hospital and Madras Medical College (Affiliated to The Tamil Nadu Dr. M.G.R Medical University) Chennai, Tamil Nadu, India
| | - Aravamudhan Ramesh
- Department of Dermatology Venereology and Leprosy, Rajiv Gandhi Government General Hospital and Madras Medical College (Affiliated to The Tamil Nadu Dr. M.G.R Medical University) Chennai, Tamil Nadu, India
| | - V Sampath
- Department of Dermatology Venereology and Leprosy, Rajiv Gandhi Government General Hospital and Madras Medical College (Affiliated to The Tamil Nadu Dr. M.G.R Medical University) Chennai, Tamil Nadu, India
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Abstract
Granulomatous slack skin syndrome is a rare variant of cutaneous T-cell lymphoma (mycosis fungoides). It is characterized clinically by redundant skin folds, which show a predilection towards flexural areas such as the axilla and the groin. Histologically, it shows a granulomatous T-cell infiltrate and loss of elastic tissue. It has an indolent but progressive course; and is usually refractory to treatment. We report a unique case of slack skin syndrome, sparing the classical sites with rapid and unusual involvement of non-intertriginous areas.
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Affiliation(s)
- S Uma Maheswari
- Department of Dermatology, Madras Medical College and Rajiv Gandhi Government General Hospital, Chennai, Tamil Nadu, India
| | - V Sampath
- Department of Dermatology, Madras Medical College and Rajiv Gandhi Government General Hospital, Chennai, Tamil Nadu, India
| | - A Ramesh
- Department of Dermatology, Madras Medical College and Rajiv Gandhi Government General Hospital, Chennai, Tamil Nadu, India
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Ramesh A, Sivayogana R, Sampath V. An outlandish association of Klinefelter syndrome. Indian J Dermatol Venereol Leprol 2017; 83:708-709. [DOI: 10.4103/ijdvl.ijdvl_944_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Abstract
Macrodystrophia lipomatosa (MDL) is a rare congenital form of localized gigantism characterized by progressive overgrowth of all mesenchymal elements with a disproportionate increase in fibro adipose tissue. Here we report a case of 20 years old male who presented with history of painless gradual enlargement of entire left upper limb since childhood. Magnetic resonance imaging and histopathology confirmed the diagnosis of macrodystrophia lipomatosa. This condition has to be differentiated from other causes of localized gigantism, since these conditions differ in their course, prognosis, complications and treatment.
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Affiliation(s)
- S Uma Maheswari
- Department of Dermatology, Madras Medical College and Rajiv Gandhi Government General Hospital, Chennai, Tamil Nadu, India
| | - V Sampath
- Department of Dermatology, Madras Medical College and Rajiv Gandhi Government General Hospital, Chennai, Tamil Nadu, India
| | - A Ramesh
- Department of Dermatology, Madras Medical College and Rajiv Gandhi Government General Hospital, Chennai, Tamil Nadu, India
| | - K Manoharan
- Department of Dermatology, Madras Medical College and Rajiv Gandhi Government General Hospital, Chennai, Tamil Nadu, India
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Abstract
Lateral medullary syndrome (LMS) is a constellation of varied neurologic manifestations seen in cerebrovascular accidents. The posterolateral part of the medulla oblongata of the brain stem and cerebellum receiving arterial blood supply from the posterior inferior cerebellar artery are the areas commonly affected. We present a case of a middle aged gentleman referred to our hospital for persistent intractable hiccups as presenting symptom of LMS. He presented to our emergency room with persistent hiccups and left sided cerebellar signs. The patient had significant past history of alcohol and tobacco (smoking) dependence since 30 years apart from being a hypertensive.
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Affiliation(s)
- V Sampath
- Spandana Nursing Home, Bengaluru, Karnataka, India
| | | | - H R Vinay
- Spandana Nursing Home, Bengaluru, Karnataka, India
| | - S Preethi
- Spandana Nursing Home, Bengaluru, Karnataka, India
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Rajamanickam M, Michael R, Sampath V, John JA, Viswabandya A, Srivastava A. Should ice be used in the treatment of acute haemarthrosis in haemophilia? Haemophilia 2013; 19:e267-8. [DOI: 10.1111/hae.12163] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/02/2013] [Indexed: 11/29/2022]
Affiliation(s)
- M. Rajamanickam
- Department of Physical Medicine and Rehabilitation; Christian Medical College; Vellore; India
| | - R. Michael
- Department of Physical Medicine and Rehabilitation; Christian Medical College; Vellore; India
| | - V. Sampath
- Department of Physical Medicine and Rehabilitation; Christian Medical College; Vellore; India
| | - J. A. John
- Department of Physical Medicine and Rehabilitation; Christian Medical College; Vellore; India
| | - A. Viswabandya
- Department of Haematology; Christian Medical College; Vellore; India
| | - A. Srivastava
- Department of Haematology; Christian Medical College; Vellore; India
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Abstract
BACKGROUND Placental nutrient flow is the primary determinant of fetal growth. This key function of the placenta depends on several growth-promoting or -suppressing imprinted genes including Insulin-like growth factor [IGF] axis genes, which regulate nutrient transfer across the placenta. However whether changes in the placental expression of these genes parallel increased fetal growth observed in the second and third trimester remains unknown. OBJECTIVE The aim of our study was to determine the ontogeny of key IGF axis genes and other growth regulating imprinted genes in the placenta and to characterize patterns of placental gene expression associated with intrauterine growth restriction (IUGR). STUDY DESIGN Real time RT-PCR analysis of 11 genes using specific probes were performed in the placental tissue collected at the time of delivery from 63 subjects with live birth pregnancies from 24 to 40 weeks gestation between 2009 -2010. RESULTS We found that paternally expressed gene ZNF127 (p < 0.001) was upregulated whereas IGF1 (p = 0.001) and maternally expressed gene PHLDA2 (p = 0.001) were downregulated with advancing gestational age. ROC analysis revealed a significant change in the expression of the above genes early in the third trimester. When compared to age-matched appropriate for gestational age (AGA) infants, expression of PHLDA2 (p = 0.03) IGF2R (p < 0.05) was upregulated in IUGR infants. Maternal age was also a significant predictor for IUGR (p = 0.05). CONCLUSION We found increased placental expression of growth-promoting imprinted genes and decreased expression of growth-suppressive imprinted genes with advancing gestational age. These changes in placental gene expression could potentially explain accelerated fetal growth seen in the third trimester. Upregulation of maternally expressed imprinted genes in IUGR population supports the "parental conflict hypothesis".
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Affiliation(s)
- N Kumar
- Medical College of Wisconsin, Neonatology Suite 410, Children's Corporate Center, 999 N. 92nd Street, Wauwatosa, WI 53226, USA.
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Dobkins K, Sampath V. Infant and Adult Preferences for Upright Faces are Driven More by High, Than Low, Spatial Frequencies. J Vis 2011. [DOI: 10.1167/11.11.453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Dobkins K, Sampath V, Wagner K. Infant Preferences for Upright Faces are Driven More by High, Than Low, Spatial Frequencies. J Vis 2010. [DOI: 10.1167/10.7.474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Norcia AM, Sampath V, Pettet M. Scale-invariant amplitude and latency in the contour-related visual evoked potential. J Vis 2010. [DOI: 10.1167/3.12.70] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Dobkins KR, Sampath V, Chen T. Adults, but not infants, use color as a segmentation cue for motion processing. J Vis 2010. [DOI: 10.1167/6.6.639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Norcia AM, Sampath V. What limits thresholds for contours in noise -- contour response strength or uncertainty? J Vis 2010. [DOI: 10.1167/3.9.119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Odabaşi A, Miles R, Balaban M, Portier K, Sampath V. Vitamin C Overcomes the Detrimental Effect of Vanadium on Brown Eggshell Pigmentation. J APPL POULTRY RES 2006. [DOI: 10.1093/japr/15.3.425] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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22
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Pei F, Bonneh Y, Sampath V, Hou C, Norcia AM. Texture detection in infants. J Vis 2002. [DOI: 10.1167/2.10.88] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Pillai B, Sampath V, Sharma N, Sadhale P. Rpb4, a non-essential subunit of core RNA polymerase II of Saccharomyces cerevisiae is important for activated transcription of a subset of genes. J Biol Chem 2001; 276:30641-7. [PMID: 11382749 DOI: 10.1074/jbc.m010952200] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [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: 11/06/2022] Open
Abstract
A major role in the regulation of eukaryotic protein-coding genes is played by the gene-specific transcriptional regulators, which recruit the RNA polymerase II holoenzyme to the specific promoter. Several components of the mediator complex within the holoenzyme also have been shown to affect activation of different subsets of genes. Only recently has it been suggested that besides the largest subunit of RNA polymerase II, smaller subunits like Rpb3 and Rpb5 may have regulatory roles in expression of specific sets of genes. We report here, the role of Rpb4, a non-essential subunit of core RNA polymerase II, in activation of a subset of genes in Saccharomyces cerevisiae. We have shown below that whereas constitutive transcription is largely unaffected, activation from various promoters tested is severely compromised in the absence of RPB4. This activation defect can be rescued by the overexpression of cognate activators. We have localized the region of Rpb4 involved in activation to the C-terminal 24 amino acids. We have also shown here that transcriptional activation by artificial recruitment of the TATA-binding protein (TBP) to the promoter is also defective in the absence of RPB4. Surprisingly, the overexpression of RPB7 (the interacting partner of Rpb4) does not rescue the activation defect of all the promoters tested, although it rescues the activation defect of the heat shock element-containing promoter and the temperature sensitivity associated with RPB4 deletion. Overall, our results indicate that Rpb4 and Rpb7 play independent roles in transcriptional regulation of genes.
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Affiliation(s)
- B Pillai
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India
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Sampath V, Zhao XJ, Caughey WS. Anesthetic-like interactions of nitric oxide with albumin and hemeproteins. A mechanism for control of protein function. J Biol Chem 2001; 276:13635-43. [PMID: 11278308 DOI: 10.1074/jbc.m006588200] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Noncovalent bonding interactions of nitric oxide (NO) with human serum albumin (HSA), human hemoglobin A, bovine myoglobin, and bovine cytochrome c oxidase (CcO) have been explored. The anesthetic nitrous oxide (NNO) occupies multiple sites within each protein, but does not bind to heme iron. Infrared (IR) spectra of NNO molecules sequestered within albumin, with NO present, support the binding of NO and NNO to the same sites with comparable affinities. Perturbations of IR spectra of the Cys(34) thiol of HSA indicate NO, NNO, halothane, and chloroform can induce similar changes in protein structure. Experiments evaluating the relative affinities of binding of NO and carbon monoxide (CO) to iron(II) sites of the hemeproteins led to evidence of NO binding to noniron, nonsulfur sites as well. With HbA, IR spectra of cysteine thiols and/or the iron(II) N-O stretching region denote changes in protein structure due to NO, NNO, or CO occupying noniron sites with an order of decreasing affinities of NO > NNO > CO. Loss of NO from some, not all, noniron sites in hemeproteins is very slow (t(1/2) approximately hours). These findings provide examples in which NO and anesthetics alter the structure and properties of protein similarly, and support the hypothesis that some physiological effects of NO (and possibly CO) result from anesthetic-like noncovalent bonding to sites within protein or other tissue components. Such bonding may be involved in mechanisms for control of oxygen transport, mitochondrial respiration, and activation of soluble guanylate cyclase by NO.
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Affiliation(s)
- V Sampath
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado 80523, USA
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Affiliation(s)
- S S Patel
- Department of Electrical & Computer Engineering, College of Engineering, University of Houston, Houston, TX 77204, USA
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Abstract
The source(s) of reactive partially reduced oxygen species associated with myocardial ischemia/reperfusion injury remain unclear and controversial. Myoglobin has not been viewed as a participant but is present in relatively high concentrations in heart muscle and, even under normal conditions, undergoes reactions that generate met (Fe3+) species and also superoxide, hydrogen peroxide, and other oxidants, albeit slowly. The degree to which the decrease in pH and the freeing of copper ions, as well as the variations in pO2 associated with ischemia and reperfusion increase the rates of such myoglobin reactions has been investigated. Solutions of extensively purified myoglobin from bovine heart in 50 mM sodium phosphate buffer were examined at 37 degrees C. Sufficiently marked rate increases were observed to indicate that reactions of myoglobin can indeed contribute substantially to the oxidant stress associated with ischemia/reperfusion injury in myocardial tissues. These findings provide additional targets for therapeutic interventions.
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Affiliation(s)
- M R Gunther
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins 80523, USA
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Ramesh A, Sampath V, Kumar KV, Janaki VR, Boopalraj JM. Cauda equina syndrome masquerading as leprosy. Indian J Lepr 1997; 69:275-9. [PMID: 9394178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- A Ramesh
- Department of Dermatology, Madras Medical College and Government General Hospital
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Abstract
Reduction of nitric oxide (NO) to nitrous oxide (N2O) is catalyzed by bovine heart cytochrome c oxidase (CcO) in anaerobic solutions at pH 7.2 and 20 degrees C. Cyanide inhibits and forms Fea3(3+)CN. The mononitrosyl (Fea3(2+)NO), but not the dinitrosyl (Fea3(2+)NO; CuB+NO), is a likely intermediate in N2O formation. One-electron reduction of NO at Fea3(2+) could yield N2O via HNO. However, a two-electron reduction of the NO ligand to give an intermediate that reacts with a second NO to give N2O and H2O appears more likely. Conversion of NO to N2O is favored by low levels of both NO and O2, higher NO levels can inhibit both cytochrome c oxidase and NO reductase activities. Raising the O2 level will favor catalysis of NO oxidation to NO2 by CcO. The reactions of NO and the specific CcO activity that occur in tissue will be critically dependent on NO, O2, and CcO levels.
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Affiliation(s)
- X J Zhao
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins 80523, USA
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Zhao XJ, Sampath V, Caughey WS. Infrared characterization of nitric oxide bonding to bovine heart cytochrome c oxidase and myoglobin. Biochem Biophys Res Commun 1994; 204:537-43. [PMID: 7980511 DOI: 10.1006/bbrc.1994.2492] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The stable binding of nitric oxide to both Cu+B and Fe2+a3 in cytochrome c oxidase is shown in infrared spectra. The N-O stretch band for Fe2+a3-NO at 1610 cm-1 is similar to the band for MbNO at 1612 cm-1. The Cu+B-NO band is at 1700 cm-1. Thus, electron donation from metal to NO is greater with Fe2+a3 than Cu+B. However, the affinity for NO is only slightly greater at Fe2+a3 than at Cu+B. In contrast CO binds stably only to Fe2+a3. Infrared spectra of oxidase, myoglobin and hemoglobin NO and CO complexes are consistent with only one stable protein structure at the ligand binding site of nitrosyls and with dynamic multiple protein conformers at carbonyl sites. The binding of NO to both Cu+B and Fe2+a3 of cytochrome c oxidase can contribute to NO cytotoxicity and to the catalysis of NO reduction to N2O and makes possible the effective use of infrared spectroscopy in investigations of Cu as well as Fe at the binuclear O2 reduction sites of oxidases.
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Affiliation(s)
- X J Zhao
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins 80523
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Dong A, Huang P, Zhao XJ, Sampath V, Caughey WS. Characterization of sites occupied by the anesthetic nitrous oxide within proteins by infrared spectroscopy. J Biol Chem 1994; 269:23911-7. [PMID: 7929038] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
We report here a comprehensive infrared spectroscopic study of the interactions between the anesthetic nitrous oxide (N2O) and six proteins: lysozyme, cytochrome c, myoglobin, hemoglobin, serum albumin, and cytochrome c oxidase. Sites occupied by N2O molecules within these proteins were characterized. Three types of hydrophobic sites were found within the proteins. One with nu 3 near 2225 cm-1 is likely to be near peptide bond carbonyls; one with nu 3 near 2219 cm-1 may be near a benzene-like structure such as the side chains of phenylalanine and tyrosine; and the other with nu 3 near 2215 cm-1 is likely to be in a nonpolar alkane-like environment provided by the side chains of Leu, Ile, and Val residues. The amount of N2O molecules bound to myoglobin increases as the pH decreases from 9.2 to 5.2. N2O-protein interactions produced no detectable changes in the ligand-binding pockets of myoglobin, hemoglobin, and cytochrome c oxidase. N2O-induced secondary structure changes were detected only in the fully reduced cytochrome c oxidase, not in the fully oxidized oxidase and the other five proteins. N2O-induced conformational changes in the alpha beta-interface of hemoglobin and the h2 and h3 alpha-helices of human serum albumin were detected by monitoring the S-H stretch vibrations of cysteine residues. These findings provide direct evidence that anesthetic N2O interacts with proteins and occupies sites in the interior of the proteins.
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Affiliation(s)
- A Dong
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins 80523
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Dong A, Huang P, Zhao X, Sampath V, Caughey W. Characterization of sites occupied by the anesthetic nitrous oxide within proteins by infrared spectroscopy. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(19)51025-0] [Citation(s) in RCA: 14] [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: 10/22/2022] Open
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Abstract
Infrared spectra permit direct measurements of cysteine thiols as well as nitric oxide bound to heme iron in human hemoglobin A nitrosyl. A single symmetric N-O stretch band of nitric oxide bound to Fe2+ is detected amid strong water and protein bands in the Hb14N16O minus Hb15N16O difference spectrum. Nitric oxide accepts electron density from metal in bent-end-on FeI2+)-14N-16O (nu NO = 1616.5 cm-1) and donates electron density to metal in linear Fe(3+)-14N-16O (nu NO = 1925 cm-1). S-H stretch bands reveal that changes in protein conformation occur at alpha-104, beta-93, and beta-112 cysteines upon conversion of deoxyHb to HbNO but that no reactions of thiols with NO occur. Furthermore, no infrared band for S-nitrosothiol is detected. Changes in amide I spectra reflect NO binding induced changes in protein secondary structure.
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Affiliation(s)
- V Sampath
- Department of Biochemistry and Molecular Biology, Colarado State University, Fort Collins 80523
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Abstract
IR spectra directly probe specific vibrators in bovine heart cytochrome c oxidase, yielding quantitative as well as qualitative information on structures and reactions at these vibrators. C-O IR spectra reveal that CO binds to Fe2+ a3 as two conformers each in isolated immobile environments sensitive to Fea and/or CuA oxidation state but remarkably insensitive to pH, medium, anesthetics, and other factors that affect activity. C-N IR spectra reveal that the one CN- that binds to fully and partially oxidized enzyme can be in three different structures. These structures vary in relative amounts with redox level, thereby reflecting dynamic electron exchange among Fea, CuA, and CuB with associated changes in protein conformation of likely significance in O2 reduction and H(+)-pumping. Azide IR spectra also reflect redox-dependent long-range effects. The amide I IR bands, due to C-O vibrators of peptide linkages and composed of multiple bands derived from different secondary structures, reveal high levels of alpha-helix (approximately 60%) and subtle changes with redox level and exposure to anesthetics. N2O IR spectra reveal that these anesthetic molecules at clinically relevant levels occupy three sites of different polarity within the enzyme as the enzyme is reversibly, but only partially, inhibited.
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Affiliation(s)
- W S Caughey
- Department of Biochemistry, Colorado State University, Fort Collins 80523
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Osmulski PA, Vossbrinck CR, Sampath V, Caughey WS, Debrunner PG. Spectroscopic studies of an insect hemoglobin from the backswimmer Buenoa margaritacea (Hemiptera:Notonectidae). Biochem Biophys Res Commun 1992; 187:570-6. [PMID: 1326950 DOI: 10.1016/0006-291x(92)91232-f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [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: 12/26/2022]
Abstract
Hemoglobin (Hb) isolated from the backswimmer Buenoa margaritacea has been analyzed spectroscopically. The met form at pH less than 6 shows a 30nm red shift in the Qv and Qo bands and a 5nm red shift in the Soret band compared to mammalian Hb, while only minor differences are seen in the spectra of the CO and O2 adducts of Hb from Buenoa and mammals. EPR spectra of the metHb show a superposition of signals; at low pH they are mainly of axial high-spin character, while at high pH a low-spin signal predominates with an O-type g-tensor (2.54, 2.61, 1.85) comparable to that of hydroxy myoglobin. Infrared spectra of Hb12C-16O at pH 8.2 reveal two major absorption bands at 1934 cm-1 and 1967 cm-1, which shift to 1892 cm-1 and 1923 cm-1, respectively, for Hb12C-18O. As isolated the Buenoa Hb consists of several isozymes, all of which have a histidine as the proximal ligand of the heme iron.
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Affiliation(s)
- P A Osmulski
- Department of Biochemistry, University of Illinois, Urbana 61801
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Olmstead MM, Sampath V, Schore NE. Structure of an oxatriquinane: cis,anti,cis-7b-methylperhydrodicyclopenta[b,d]furan-1,6-dione. Acta Crystallogr C 1987. [DOI: 10.1107/s0108270187089546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Olmstead MM, Hope H, Sampath V, Schore NE. Structures of trans-6,7-dibromo-8-oxabicyclo[3.2.1]octan-3-one, C7H8Br2O2, and 6-bromo-8-oxabicyclo[3.2.1]oct-6-en-3-one, C7H7BrO2. Acta Crystallogr C 1984. [DOI: 10.1107/s0108270184003498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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