Gd2O3-modulated borate glass for the enhancement of near-infrared emission via energy transfer from Gd3+ to Nd3

(Li2O)0.20(SrO)0.30(Nd2O3)0.01(B2O3)0.49-x(Gd2O3)x, where x = 0, 3, 5, 7, and 10 mol%, glass was melt-quenched to test it as a laser source in the near-infrared (NIR) region. The structural modification, absorption spectra, Judd-Ofelt (J-O) parameters, luminescence spectra, radiative laser parameters, lifetimes, XRD, and FTIR spectra were studied. Luminescence spectra excited at λexc = 584 nm revealed the highest intensity peak at 1073 nm due to the transition of 4F3/2 → 4I11/2. An important phenomenon of concentration quenching was observed and optimized luminescence was achieved with the sample having the concentration x = 07 mol%. The lifetimes of the donor and acceptor and energy transfer from gadolinium to neodymium were obtained from the luminescence decay kinetics. The findings show that Nd-doped Gd2O3-modified glass materials have potential as NIR laser sources.

P-152 COMPARISON OF ENHANCED-VIEW TOTALLY EXTRAPERITONEAL (ETEP) AND TRANSABDOMINAL (TARM) MINIMAL ACCESS TECHNIQUES FOR RETROMUSCULAR PLACEMENT OF PROSTHESIS IN THE TREATMENT OF IRREDUCIBLE MIDLINE VENTRAL HERNIA

Aim

Retromuscular or sublay meshplasty has been advocated to reinstate abdominal wall strength following ventral hernia repair while avoiding complications like visceral adhesions, fistula formation and mesh infection. We aim to compare two minimally invasive approaches of sublay hernioplasty for irreducible ventral midline hernia with respect to their efficacy and safety.

Material & Methods

We performed a retrospective study of 73 patients operated for primary and recurrent irreducible ventral midline hernia by eTEP or TARM repair with sublay meshplasty. We compared the intraoperative and post-operative complications, post-operative pain score, subjective technical ease of procedure, patient satisfaction and recurrence after 3 months and 12 months of surgery.

Results & Conclusion

There was no significant difference in the outcome of surgery and complications by the two techniques. However, there was a significant subjective technical ease in the TARM group (n=35) due to ergonomic port placement and adhesiolysis and reduction of hernia contents done under vision. The number of ports used and post-operative pain score were higher in the TARM group as compared to that of the eTEP group. 96% of the patients belonging to both groups were satisfied with their surgery after a year on telephonic follow-up. However, a multicentric study with a larger sample size would be required to establish the advantage of one technique over the other.

A novel protein truncating mutation in L2HGDH causes L-2-hydroxyglutaric aciduria in a consanguineous Pakistani family

BACKGROUND

L-2-hydroxyglutaric aciduria (L2HGA) is a rare neurometabolic disorder that occurs due to accumulation of L-2-hydroxyglutaric acid in the cerebrospinal fluid (CSF), plasma and urine. The clinical manifestation of L2HGA includes intellectual disability, cerebellar ataxia, epilepsy, speech problems and macrocephaly.

METHODS

In the present study, we ascertained a multigenerational consanguineous Pakistani family with 5 affected individuals. Clinical studies were performed through biochemical tests and brain CT scan. Locus mapping was carried out through genome-wide SNP genotyping, whole exome sequencing and Sanger sequencing. For in silico studies protein structural modeling and docking was done using I-TASSER, Cluspro and AutoDock VINA tools.

RESULTS

Affected individuals presented with cognitive impairment, gait disturbance, speech difficulties and psychomotor delay. Radiologic analysis of a male patient revealed leukoaraiosis with hypoattenuation of cerebral white matter, suggestive of hypomyelination. Homozygosity mapping in this family revealed a linkage region on chromosome 14 between markers rs2039791 and rs781354. Subsequent whole exome analysis identified a novel frameshift mutation NM_024884.3:c.180delG, p.(Ala62Profs*24) in the second exon of L2HGDH. Sanger sequencing confirmed segregation of this mutation with the disease phenotype. The identification of the most N-terminal loss of function mutation published thus far further expands the mutational spectrum of L2HGDH.

Antibiotic resistance in patients with chronic ear discharge awaiting surgery in Nepal

SETTING

Biratnagar Eye Hospital, Biratnagar, Nepal, which offers ear surgery for chronic suppurative otitis media (CSOM).

OBJECTIVE

In patients with CSOM awaiting surgery, to determine the 1) sociodemographic characteristics 2) bacterial isolates and their antibiotic resistance patterns and 3) characteristics of those refused surgery, including antibiotic resistance.

DESIGN

A cohort study using hospital data, January 2018-January 2020.

RESULTS

Of 117 patients with CSOM and awaiting surgery, 64% were in the 18-35 years age group, and 79% were cross-border from India. Of 118 bacterial isolates, 80% had Pseudomonas aeruginosa and 16% had Staphylococcus aureus. All isolates showed multidrug resistance to nine of the 12 antibiotics tested. The lowest antibiotic resistance in P. aeruginosa was for vancomycin (29%) and moxifloxacin (36%), and for S. aureus, this was vancomycin (9%) and amikacin (17%). Fourteen (12%) patients underwent surgery: myringoplasty (n = 7, 50%), cortical mastoidectomy with tympanostomy (n = 4, 29%) and modified radical mastoidectomy (n = 3, 21%). Those infected with P. aeruginosa and with resistance to over six antibiotics were significantly more likely to be refused for surgery.

CONCLUSION

Patients awaiting ear surgery were predominantly infected with multidrug-resistant P. aeruginosa and were consequently refused surgery. This study can help inform efforts for improving surgical uptake and introducing cross-border antimicrobial resistance surveillance.

Fabrication of bulk heterojunction organic solar cells with different configurations using electrospray

In this work, we fabricated bulk heterojunction (BHJ) organic solar cells (OSCs) using electrospray deposition (ESD) with two different device configurations. ITO/PEDOT:PSS/P3HT: PCBM/Ca/Al and ITO/ZnO and TiO2/P3HT: PCBM/MoO3/Ag, termed as direct and inverted OSCs, respectively. In ZnO/ TiO2 -based inverted solar cells, ZnO/ TiO2 films were synthesized by sol-gel process and deposited on ITO deposited glass substrates using the spin-coating technique. P3HT/PCBM blend layers were deposited by using electrospray deposition (ESD). To observe the thermal effects on the device efficiencies, the devices were annealed at different temperatures (up to 140 °C). The cell’s performance parameters were compared at an annealing temperature of 120 °C. Comparing the performance parameters of both types of OSCs at an annealing temperature of 120 °C, the power conversion efficiency (PCE) the 1.62% is found for direct-structured OSC while 1.57% and 1.0% for ZnO/ TiO2-based inverted structures, respectively. Interestingly, the enhanced device performance parameters were obtained with oxides-based OSCs. Compared to ZnO-based inverted OSC, the TiO2-based inverted OSC has lower efficiency which might be due to the highly resistive surface of TiO2 with deep-level traps. These traps can be reduced by light soaking to achieve the optimal power conversion efficiency.

Post-trial Access in Maternal Vaccine Trials

Provisions for post-trial access (PTA) of the experimental intervention are required before the start of a clinical trial. Although there has been ample attention for PTA in the context of preventive vaccine research, discussions on PTA barely include maternal vaccine trials in which mother-infant pairs are exposed to the intervention. In maternal vaccination trials, specific PTA arrangements are required because pregnancy is transient and PTA may apply to the next pregnancy or the child. In this article, we examine the application and adherence to PTA in the context of maternal vaccine trials. We focused on differences between publications before and after 2000 when international ethical guidance documents formalized PTA requirements. Randomized maternal vaccine trials were included after a systematic search for clinical trials in phases II and III with a maternal vaccine as intervention. We used PTA as defined at the time of publication in the World Medical Association's Declaration of Helsinki (DoH) or in the ethical guidelines of the Council for International Organizations of Medical Sciences (CIOMS). In addition, we investigated whether PTA was included in the trial design. Therefore, we contacted principal investigators (PI's) of the publications found in the review to fill out a questionnaire regarding provisions for PTA. Before and after 2000, no trial articles examined in the systematic review described PTA in their trial publication (0/7, 0% and 0/17, 0%, respectively). In addition, more than half of the PI's of the trials found were not familiar with PTA recommendations in international ethical guidelines. Most cases of PTA included making knowledge available by publishing the results of the trial. The revision of the DoH in 2002 and the CIOMS ethical guidelines in 2002 has not resulted in increased PTA provisions for maternal vaccination trials. PTA is a shared responsibility of various stakeholders including sponsors, Institutional Review Boards, regulators, political entities, and researchers. Inclusion of PTA provisions in trial protocols and publications on maternal vaccination trials is essential to increase transparency on the form and content of these provisions.

Right Atrial Myxoma: An Uncommon Presentation

There are two types of tumors found in the cardiac chamber. These are divided into primary intra-cardiac tumors and secondary intra-cardiac tumors. Primary intra cardiac tumors are rare and among them 29% are myxomas. Majority of them are found in the left atrium. Here, we report a case of a myxoma in the right atrium with hepatomegaly and Hepatitis B virus infection. The coexistence of all these conditions is very rare. A 52 years old patient presented with history of shortness of breath on exertion along with fever and generalized weakness for 6 months which aggravated lately for last 2 months. He was then taken for better medical care and hospitalization. On cardiac evaluation he had soft S1 and S2 over the tricuspid region on the right lower parasternal region. He had bilateral mild pitting pedal edema. On further examination, it was revealed that he had mild tender hepatomegaly with jaundice. His blood analysis for HBsAg was positive. Echocardiogram showed right atrial myxoma of 14.3cm² almost completely occupying the right atrium and even protruding into the Inferior Venacava however not fully obstructing it. The inferior vena cava size was mildly dilated (22mm). Abdominal ultrasound report showed hepatomegaly (17.6cm) with coarse hepatic parenchyma. In this report, we emphasize the rarity of myxoma in the Right Atrium, its difficult diagnosis because of the location and the atypical presentation in the echocardiograph.

Comparison of IOL power calculation formulae for pediatric eyes

PurposeTo evaluate and compare the accuracy of modern intraocular lens (IOL) power calculation formulae in pediatric eyes and compare prediction error (PE) obtained with manufacturer's vs personalized lens constant.Patients and methodsAn observational case study was conducted in 117 eyes (117 patients) undergoing pediatric cataract surgery with IOL implantation. PE was calculated as predicted refraction minus actual postoperative refraction, and absolute PE as absolute difference independent of the sign, (APE)=predicted refraction minus actual postoperative refraction. This was done for each formula using manufacturer's and personalized lens constant. Further, PE and APE were evaluated according to axial length (AL).ResultsMean age of children was 2.97 years. About 66/117 eyes (56.4%) were below 2 years of age. Using Holladay 2, Holladay 1, Hoffer Q, and SRK/T formulae with manufacturer's lens constant, mean PE was 0.36, 0.41, 0.69, and 0.28 diopter (D), respectively. With personalized lens constant, it was 0.16, 0.15, 0.50, and -0.12 D, respectively. Difference in mean PE between the formulae was statistically significant (P<0.0001). SRK/T and Holladay 2 formulae had the least PE, both with manufacturer's and personalized constant. For eyes with AL<20 mm, SRK/T and Holladay 2 formulae gave the least PE. Personalizing the lens constant led to a decrease in mean PE in all formulae, except the Hoffer Q formula. However, personalizing the lens constant did not significantly improve the APE. At least 21% eyes had an APE of >2 D with all formulae, even with personalized lens constants.ConclusionIn pediatric eyes, SRK/T and the Holladay 2 formulae had the least PE. Personalizing the lens formula constant did reduce the PE significantly for all formulae except Hoffer Q. In extremely short eyes (AL<20 mm), SRK/T and Holladay 2 formulae gave the best PE.

Analysis of pulmonary non-tuberculous mycobacterial infections after lung transplantation

PURPOSE

Non-tuberculous mycobacteria (NTM) are important pathogens in lung transplant recipients. This study describes the spectrum of NTM respiratory tract infections and examines the association of NTM infections with lung transplant complications.

METHODS

Data from 208 recipients transplanted from November 1990 to November 2005 were analyzed. Follow-up data were available to November 2010. Lung infection was defined by bronchoalveolar lavage, sputum, or blood cultures in the appropriate clinical setting. All identified NTM respiratory tract infections were tabulated. The cohort of patients with NTM lung infections (NTM+) were compared to the cohort without infection (NTM-). Univariate and multivariate analysis was performed to determine characteristics associated with NTM infection. Survival analyses for overall survival and development of bronchiolitis obliterans syndrome (BOS) were also performed.

RESULTS

In total, 52 isolates of NTM lung infection were identified in 30 patients. The isolates included Mycobacterium abscessus (46%), Mycobacterium avium complex (MAC) (36%), Mycobacterium gordonae (9%), Mycobacterium chelonae (7%), and Mycobacterium fortuitum (2%), with multiple NTM isolates seen on 3 different occasions. The overall incidence was 14%, whereas cumulative incidences at 1, 3, and 5 years after lung transplantation were 11%, 15%, and 20%, respectively. Comparisons between the NTM+ and NTM- cohorts revealed that NTM+ patients were more likely to be African-American and have cytomegalovirus mismatch. Although no difference was seen in survival, the NTM+ cohort was more likely to develop BOS (80% vs. 58%, P = 0.02). NTM+ infection, however, was not independently associated with development of BOS by multivariate analysis.

CONCLUSION

With nearly 20 years of follow-up, 14% of lung recipients develop NTM respiratory tract infections, with M. abscessus and MAC more commonly identified. M. gordonae was considered responsible for nearly 10% of NTM infections. Although survival of patients with NTM infections is similar, a striking difference in BOS rates is present in the NTM+ and NTM- groups.

Xpert(®) MTB/RIF under routine conditions in diagnosing pulmonary tuberculosis: a study in two hospitals in Pakistan

Xpert(®) MTB/RIF testing was offered to consecutive patients with presumptive tuberculosis (TB) attending two hospitals in Pakistan during April-May 2012, in addition to routine diagnostic protocol (smear microscopy, chest radiography and clinical judgement). We assessed the relative contribution of each tool in detecting pulmonary TB under routine conditions. Of 606 participants, 121 (20%) were detected as pulmonary TB: 46 (38%) by microscopy, 38 (31%) by Xpert alone and 37 (31%) on clinical and radiological grounds; 41 (65%) were detected by both Xpert and microscopy. One patient had rifampicin resistance. Although Xpert detected approximately twice as many TB cases as microscopy (n = 79, 65%), clinical judgement remained favoured by clinicians even when smear and Xpert were negative.

Rhabdomyolysis Due to Severe Hypophosphatemia in Diabetic Ketoacidosis

Rhabdomyolysis is a syndrome characterized by injury to skeletal muscle fibers with disruption and release of toxic metabolites into circulation. It is characterized by triad of muscle weakness, myalgia and dark urine and is associated with increased creatine kinase and lactate dehydrogenase. A severely malnourished 10 year old girl with severe diabetic ketoacidosis as hemr initial presentation of type 1 diabetes mellitus developed rhabdomyolysis (CK- 12,000 U/L) with non-oliguric renal failure during her initial course of hospital stay. The possible cause of her RM was attributed to severe hypophosphatemia (minimum serum phosphate, 0.8 mg/dL). Management of diabetic ketoacidosis phosphate supplementation and urinary alkalinization with diuresis improved her clinical course. She was discharged on Day 9 with Insulin. We recommend frequent monitoring of serum phosphate during early period of DKA, particularly in malnourished children, and its normalization in case of severe hypophosphatemia.

A comparative study of sexual dysfunction in schizophrenia patients taking aripiprazole versus risperidone

BACKGROUND

Sexual dysfunction due to antipsychotics is a significant problem encountered with first-generation antipsychotics. Even the second-generation antipsychotics like risperidone are not free of sexual dysfunction due to its D2 blocking properties leading to hyperprolactinaemia. Newer antipsychotic aripiprazole, partial dopamine agonist, with neutral effect on prolactin level or even decreasing it, is associated with avoidance of sexual dysfunction.

OBJECTIVES

To assess the effect of risperidone and aripiprazole on sexual function of schizophrenic patients.

METHODS

This was an open-label, cross-sectional, observational study conducted at College of Medical Sciences, Bharatpur. Schizophrenic patients attending OPD and inpatient, taking risperidone or aripiprazole for at least two months were included in this study. Forty one patients, without chronic medical illness and sexual dysfunction before starting drugs, with informed consent were studied during Jan 2012 and Aug 2012.

RESULTS

Changes in sexual activity was found in 11(55%) of those taking risperidone while, only 3(14.3%) had any kind of sexual difficulty. This was statistically significant (p=0.006). Majority, 92.7% of the patients did not report about changes in sexual activity spontaneously.

CONCLUSION

Sexual dysfunction was statistically significantly higher in those taking risperidone. Prevalence of sexual dysfunction was low with aripiprazole. Except those having poor sexual functions due to the drugs, the majority had to be specifically inquired about the effects of drug on sex life.

A study of clinico-demographic profile of patients with dissociative disorder

Objectives To study the clinical and socio demographic profile of patients with dissociative disorder and their comorbid mental illness. Materials and methods Fifty-one patients of dissociative disorder presenting to emergency and outpatient department of Psychiatry at College of Medical Sciences Teaching Hospital during the period from Jan to March 2012 were included. International statistical classification of diseases and related health problems tenth edition, diagnostic criteria for research (ICD-10, DCR) was used. Results Out of 51 patients, the majority 24 (47.1%), were in the age group 15-29. However the age of presentation ranged from 9-45 years. The females were more, 44 (86.3%) as compared to males 7 (13.7%). The majority of patients had low level of education with none of the patients having education above intermediate level. The majority of patients, 27(52.9%) belonged to lower middle class. 49% of the patients presented with dissociative convulsions, 15.7% with dissociative motor disorders, 15.7% with dissociative stupor, 11.8% with dissociative anesthesia and sensory loss and 7.8% with trance and possession disorder. Depressive illness was found co-morbid with dissociative disorder in 33.3%, borderline personality disorder in 9.8% and histrionic personality disorder in 7.8%. There was history of immediate stressful events that supposedly precipitated the event in 76.5%. Conclusion Dissociative disorder mainly affects young female of lower socio-economic and educational status with history of immediate stressful life events precipitating the illness. Journal of College of Medical Sciences-Nepal, 2012, Vol-8, No-3, 30-35 DOI: http://dx.doi.org/10.3126/jcmsn.v8i3.8683

Ethical tradeoffs in trial design: case study of an HPV vaccine trial in HIV-infected adolescent girls in lower income settings

The Declaration of Helsinki and the Council of the International Organization of Medical Sciences provide guidance on standards of care and prevention in clinical trials. In the current and increasingly challenging research environment, the ethical status of a trial design depends not only on protection of participants, but also on social value, feasibility, and scientific validity. Using the example of a study assessing efficacy of a vaccine to prevent human papilloma virus in HIV-1 infected adolescent girls in low resource countries without access to the vaccine, we compare several trial designs which rank lower on some criteria and higher on others, giving rise to difficult trade-offs. This case demonstrates the need for developing more nuanced guidance documents to help researchers balance these often conflicting criteria.

Probable Phaeoacremonium parasiticum as a cause of cavitary native lung nodules after single lung transplantation

Lung nodules after lung transplantation most often represent infection or post-transplant lymphoproliferative disorder in the allograft. Conversely, native lung nodules in single lung transplant recipients are more likely to be bronchogenic carcinoma. We present a patient who developed native lung cavitary nodules. Although malignancy was anticipated, evaluation revealed probable Phaeoacremonium parasiticum infection. Phaeoacremonium parasiticum is a dematiaceous fungus first described as a cause of soft tissue infection in a renal transplant patient. Lung nodules have not been previously described and this is the first case, to our knowledge, of P. parasiticum identified after lung transplantation.

Antioxidant and hepatoprotective action of Asparagus racemosus Willd. root extracts

The antioxidant activities of the crude hydro-alcoholic extract (CE) and its four fractions viz. methanol (MF), ethyl acetate (EF), n-Butanol (BF), and precipitated aqueous (PAF) of A.racemosus roots tested decreased in the order of EF > MF > CE > BF > PAF when investigated by DPPH free radical scavenging assay. Under iron induced lipid peroxidation almost similar results were observed except that the activity was more in PAF than BF. Hepatoprotective activity of the extracts was also demonstrable in vivo by the inhibition of-CCl4 induced formation of lipid peroxides in the liver of rats by pretreatment with the extracts. CCl4-induced hepatotoxicity in rats, as judged by the raised serum enzymes viz. glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, alkaline phosphatase and total and direct bilirubin as well as oxidant enzyme viz. malon dialdehyde were prevented, while antioxidant enzymes viz. superoxide dismutase, reduced glutathione and catalase were elevated by pretreatment with the extracts, demonstrating the potent hepatoprotective action of the roots of A. racemosus.

Study of psychiatric disorders among nepalese patients working abroad and their family members

This study was carried out among the patients working abroad and their family members, having various psychiatric disorders. 80 patients attending psychiatry OPD between the age of 15 to 65 years both male and female in the period of July 2009 to July 2010 were included. The results were tabulated as per the diagnostic criteria of International Classification of Diseases (ICD-10). Out of total 80 patients, 41 were males and 39 were females, whose husbands were working abroad. 30 cases were of depression,out of which 16 were males and 14 were females.18 cases were having anxiety disorders out of which 5 were males and 13 were females. 12 cases were suffering from psychotic disorders out of which 10 were males and 2 were females.7 cases were having dissociative disorders with 1 male and 6 females.4 cases were having somatoform disorders with 2 males and 2 females.1 male and 1 female were suffering from mania.1 male and 1 female were suffering from bipolar affective disorder. 2 males were alcohol dependent and 2 males were having obsessive compulsive disorder. 1 male was having organic psychosis. Journal of College of Medical Sciences-Nepal,2011,Vol-6,No-4, 1-6 DOI: http://dx.doi.org/10.3126/jcmsn.v6i4.6718

A comparision of efficacy of risperidone and olanzapine in schizophrenia patients

Schizophrenia is a leading worldwide mental health problem. It is also one of the common and challenging problems in Nepal. Risperidone and olanzapine is one of the major antipsychotic drug used for schizophrenia patients, however their efficacy is not compared in Nepal.To assess the efficacy of risperidone and olanzapine in schizophrenia patients in Nepalese context. An open-label, randomized, comparative, prospective study was done for 6 weeks. Total of 63 patients attending Psychiatry OPD in Jan to July 2008 at TUTH who could be available for close follow up were enrolled with consent. Risperidone was given in dose of 3-6 mg and Olanzapine in the dose of 15-20 mg per day. Efficacy and tolerability was assessed using PANSS, CGI, and UKU side-effect checklist. Both groups showed improvement in the entire positive, negative and general psychopathology subscales without significant difference in the two groups. Regarding tolerability, olanzapine was found to have significant sedation, weight gain while with risperidone extrapyramidal side-effects, palpitations, sexual side-effects were significant. Risperidone and olanzapine both are efficacious in the treatment of schizophrenia. Both the drugs have their own side-effects. Long-term efficacy and tolerability needs to be studied. As it has been seen in the ongoing studies, long-term use and side-effect profile, drop-out rates and the increase in metabolic syndromes need more consideration.DOI: http://dx.doi.org/10.3126/jcmsn.v7i3.6706 Journal of College of Medical Sciences-Nepal, 2011, Vol-7, No-3, 29-35

Solitary fibrous tumour presenting as a pedunculated lung mass with associated lung atresia: report of a case

This case report describes a solitary fibrous tumour presenting as a pedunculated mass arising from an almost completely atretic right middle lobe of lung. The intraoperative findings and pathologic diagnostic criteria used are described. To our knowledge, this is the first case report of a solitary fibrous tumour associated with partial lung atresia.

Photometric calibration for quantitative spectral microscopy under transmitted illumination

Over the past decade, there have been significant developments in the mechanisms for examination of biological and material samples. These developments exploit techniques in light microscopy to elucidate specific parts of cells and tissues, as well as inorganic particles. In recent years, spectral microscopy has become more prevalent for characterization of samples. Simultaneously, sensor technology has progressed as well and modern charge-coupled devices (CCD) cameras are now capable of achieving high spatial resolution and high sensitivity measurements of signals in the optical microscope. One major impediment in obtaining absolute quantitative information of imaged samples is the lack of automated photometric calibration mechanisms for spectral microscopes. In this paper, we present a methodology for achieving photometric calibration of an automated spectral imaging system targeted towards examination of biological samples. By acquiring spatial and spectral data simultaneously, spectral imaging allows one to exploit physical connections between a particle's morphology and its characteristic response to the optical spectrum. In composite biological material, the interpretation of the spectra is a complicated problem. This is because any light source and charge-coupled device camera used for data acquisition does not have a uniform illumination spectra and quantum efficiency, respectively, across the emitted light spectra. To balance the spectral response across individual wavelengths, our method modulates the exposure duration for the charge-coupled device camera during image acquisition. We present an image similarity based method to calibrate the system. Experiments to test the effectiveness of the calibration method under the various image similarity metrics are presented along with results to show the calibrated system's ability to accurately measure spectra based on the measured transmission profiles of optical filters.

Current trends in cell therapy for pediatric acquired brain injury

Pediatric traumatic brain injury (TBI) represents a major burden on healthcare worldwide. In the United States, TBI accounts for 435000 Emergency Department visits, 37000 hospital admissions, and approximately 2500 deaths each year. While aggressive early rehabilitation has shown some functional improvement, the acute care of TBI with focus on controlling intracranial pressure while maintaining adequate cerebral perfusion has not shown the ability to reverse neuronal injury on either a cellular or subcellular level. Preliminary investigation into the use of cell therapeutics has shown promise for the treatment of TBI in animal models. While progenitor cells may potentially act via altering the intracerebral milieu (modulation of inflammatory response and trophic factor secretion), the exact mechanism remains controversial. In addition, traditional delivery vehicles (intravenous, intra-arterial, intrathecal injections, and direct implantation) have shown significant barriers to translation coupled with inconsistent results. Therefore, investigation into novel delivery vehicles such as nanofiber scaffolds and hydrogels could enhance transplant cell viability, engraftment, and efficacy. Overall, a large amount of preclinical work remains to clearly define optimal progenitor cell type, dosage, and delivery vehicle. The optimal therapeutic benefit may be seen using a combination of therapies (controlled hypothermia, hypertonic therapy, and/or cellular therapeutics) to attack the complex pathophysiology of TBI at multiple points.

An optimised radial basis function algorithm for fast non-rigid registration of medical images

The registration of multi-modal medical image data is important in the fields of image guided surgery and computer aided medical diagnosis. Registration accuracy is of utmost importance in both fields, however in the former, the speed of registration is equally important. In this paper, we present a point-based 'fast' non-rigid registration algorithm which exhibits significant speedups as compared to the non-optimised equivalent algorithm. Additionally, we make use of the parallel nature of the graphics processing unit (GPU) of the video adapter card of a standard PC to gain further speedups. The algorithm achieved sub-second performance when tested on the registration of MR with CT image data of size 256(3).

Vascular endothelial growth factor is up-regulated after status epilepticus and protects against seizure-induced neuronal loss in hippocampus

Vascular endothelial growth factor (VEGF) is a protein factor which has been found to play a significant role in both normal and pathological states. Its role as an angiogenic factor is well-established. More recently, VEGF has been shown to protect neurons from cell death both in vivo and in vitro. While VEGF's potential as a protective factor has been demonstrated in hypoxia-ischemia, in vitro excitotoxicity, and motor neuron degeneration, its role in seizure-induced cell loss has received little attention. A potential role in seizures is suggested by Newton et al.'s [Newton SS, Collier EF, Hunsberger J, Adams D, Terwilliger R, Selvanayagam E, Duman RS (2003) Gene profile of electroconvulsive seizures: Induction of neurotrophic and angiogenic factors. J Neurosci 23:10841-10851] finding that VEGF mRNA increases in areas of the brain that are susceptible to cell loss after electroconvulsive-shock induced seizures. Because a linear relationship does not always exist between expression of mRNA and protein, we investigated whether VEGF protein expression increased after pilocarpine-induced status epilepticus. In addition, we administered exogenous VEGF in one experiment and blocked endogenous VEGF in another to determine whether VEGF exerts a neuroprotective effect against status epilepticus-induced cell loss in one vulnerable brain region, the rat hippocampus. Our data revealed that VEGF is dramatically up-regulated in neurons and glia in hippocampus, thalamus, amygdala, and neocortex 24 h after status epilepticus. VEGF induced significant preservation of hippocampal neurons, suggesting that VEGF may play a neuroprotective role following status epilepticus.

Tuberculosis patient adherence to direct observation: results of a social study in Pakistan

A randomized controlled trial was carried out in Pakistan in 1999 to establish the effectiveness of the direct observation component of DOTS programmes. It found no significant differences in cure rates for patients directly observed by health facility workers, community health workers or by family members, as compared with the control group who had self-administered treatment. This paper reports on the social studies which were carried out during and after this trial, to explain these results. They consisted of a survey of all patients (64% response rate); in-depth interviews with a smaller sample of different types of patients; and focus group discussions with patients and providers. One finding was that of the 32 in-depth interview patients, 13 (mainly from the health facility observation group) failed to comply with their allocated DOT approach during the trial, citing the inconvenience of the method of observation. Another finding was that while patients found the overall TB care approach efficient and economical in general, they faced numerous barriers to regular attendance for the direct observation of drug-taking (most especially, time, travel costs, ill health and need to pursue their occupation). This may be one of the reasons why there was no overall benefit from direct observation in the trial. Provider attitudes were also poor: health facility workers expressed cynical and uncaring views; community health workers were more positive, but still arranged direct observation to suit their, rather than patients', schedules. The article concludes that direct observation, if used, should be flexible and convenient, whether at a health facility close to the patient's home or in the community. The emphasis should shift in practice from tablet watching towards treatment support, together with education and other adherence measures.

Do private doctors follow national guidelines for managing pulmonary tuberculosis in Pakistan?

As private medical practitioners play a major role of in providing care to pulmonary tuberculosis (TB) patients, a survey was made of knowledge and practice in 2 cities in Pakistan. Only 1 of the 245 physicians was aware that cough > 3 weeks alone is the main symptom suggesting pulmonary TB. The majority diagnosed (80%) and treated (83%) cases themselves without referral. Less than 1% relied on sputum microscopy alone for diagnosis. None of the practitioners were following National TB Control guidelines for prescribing drugs and none ensured compliance with anti-TB treatment under supervision of a doctor/health worker. Only 3% kept records of pulmonary TB patients. None of the physicians assessed the effectiveness of treatment with sputum microscopy alone; the majority (76%) used only clinical assessment.

Gender perspectives on knowledge and practices regarding tuberculosis in urban and rural areas in Pakistan

We investigated gender differences in knowledge of and attitude towards tuberculosis (TB) in urban and rural communities in Sindh province, Pakistan. Knowledge of symptoms was generally deficient, particularly in rural females. Regarding TB prevention, 22.4% of rural and 14.4% of urban males said completing treatment was important; only 9.8% of rural and 7.1% of urban females agreed. Doctors were an important source of information in rural areas and 60.9% of rural males said they would only stop treatment on a doctor's advice. In contrast, > 65% of respondents in urban areas said they would stop treatment when symptoms ended. Our study highlights the need to increase population awareness about TB in Sindh.

Prospective evaluation of a new self-expanding plastic stent for inoperable esophageal strictures

BACKGROUND

High stent cost is considered the major drawback of self-expanding metal stents for dysphagia palliation in patients with inoperable esophageal strictures. We report our experience with a self-expanding plastic (Polyflex) stent, the cost of which is half that of the metal stents.

METHODS

Between September 1999 and April 2001, 16 dysphagic patients (15 men; mean age, 69.4 +/- 14.5 years; range, 49-100 years; mean dysphagia score, 3.31 +/- 0.6) with esophageal strictures who underwent Polyflex stent placement (insertion device diameter, 12-14 mm; postexpansion inner stent diameter, 16-21 mm; stent length, 9, 12, and 15 cm) were studied prospectively. The strictures were caused by postsurgical recurrence of gastric/esophageal cancer at the anastomotic site in five patients, primary esophageal cancer in four patients, esophagocardia junction cancer in four patients, metastatic mediastinal lymph nodes from a primary lung cancer invading the esophagus in 1 patient, and benign peptic stricture in two elderly patients. All the patients were prospectively followed until death.

RESULTS

Stent insertion was technically successful in 12 patients (75%). Stent placement failed in four patients (25%) because of failure to pass the delivery catheter across the stricture in three patients and failure of the stent to open in one patient. Early and late stent migration occurred in two patients and 1 patient, respectively. Tumor overgrowth occurred in 1 patient. The mean dysphagia score 7 days after stent placement was 1.1 +/- 0.9. Mean survival was 100.6 +/- 71.2 days (range, 8-225 days).

CONCLUSION

Self-expanding Polyflex stents are safe and effective for inoperable esophageal strictures and have an acceptable technical success rate. Further experience, better selection criteria, and design improvements should improve results.

Endoscopic treatment of extrahepatic bile duct strictures in patients with portal biliopathy carries a high risk of haemobilia: report of 3 cases

Extrahepatic portal venous obstruction can be associated with bile duct abnormalities, the entity being called portal biliopathy. Three cases are reported of extrahepatic bile duct strictures in patients with portal biliopathy who developed haemobilia during endotherapy. Although endoscopic therapy with stent placement can be successful in patients with portal biliopathy and could also lead to permanent stricture resolution, procedure-related haemobilia is not as uncommon as previously held. Shunt surgery could be a better option in fit patients, since it could provide definitive treatment in a young patient with an otherwise normal life expectancy.

Treatment of unresectable pancreatic carcinoma by intraluminal brachytherapy in the duct of Wirsung

BACKGROUND AND STUDY AIMS

Our aim was to evaluate the feasibility and clinical outcome of intraluminal brachytherapy (ILBT) in the duct of Wirsung in patients with unresectable pancreatic adenocarcinoma.

PATIENTS AND METHODS

Nine patients (eight men, one woman; mean age 72.4 +/- 9.1, range 52 - 80) with unresectable pancreatic adenocarcinoma of the head or body underwent ERCP for biliary and/or pancreatic stent placement and placement of a nasopancreatic drain with/without nasobiliary drain. The ILBT dose administered was 30 - 50 Gy calculated at 1 cm from the iridium-192 wire axis. Seven patients received ILBT from the duct of Wirsung whereas two patients received dual-duct ILBT (duct of Wirsung and the common bile duct). Three patients received combined-modality treatment (ILBT with external beam radiotherapy and 5-fluorouracil). The patients were prospectively followed up.

RESULTS

No endoscopy-related complications occurred. No radiation-related toxicity occurred in patients treated with ILBT alone. One patient undergoing combined-modality treatment developed gastric bleeding. Intraluminal source dislodgement occurred in three patients. Obvious tumor mass reduction of greater than 50 % was seen in three patients at 8 weeks after brachytherapy. Median survival was 11 months (range 6 - 37 months) and the 1-year and 3-year actuarial survival rates were 44 % and 15 %, respectively.

CONCLUSION

Intraluminal brachytherapy in the duct of Wirsung in patients with unresectable pancreatic carcinoma is safe and feasible. Further clinical trials are warranted.

Endoscopic palliation of unresectable malignant oesophageal strictures with self-expanding metal stents: comparing Ultraflex and Esophacoil stents

BACKGROUND

Two types of self-expanding metal stents to palliate dysphagia in patients with unresectable malignant oesophageal strictures have been compared.

METHODS

From February 1996 to October 2000, 50 metal stents (23 covered Ultraflex and 27 Esophacoil) were placed in 50 patients (40 males, mean age: 67+/-12 years, range: 33-100, mean dysphagia score: 3.18+/-0.66) with unresectable malignant oesophageal strictures. Patients were followed until death. A retrospective review has been made of a prospectively collected database.

RESULTS

The two groups were comparable as far as concerns degree of dysphagia, location and stricture length. Stent placement was successful in all cases. Covered Ultraflex stent was placed in 2 patients with oesophagobronchial fistula. No procedure-related deaths were seen. Early severe complications occurred in 2 patients (perforation in 1 and tumour bleeding in 1, in the Esophacoil group). Nine patients and 1 patient complained of pain following Esophacoil and Ultraflex stent placement, respectively. Late complications were asymptomatic rupture of distal Esophacoil rings in 2 patients, symptomatic Ultraflex stent migration in 2 and tumour overgrowth in 3 (Esophacoil 1, Ultraflex 2). Mean dysphagia score at 4 weeks after stent placement was 1.9+/-0.77. Mean survival was 177+/-109 days (range: 35-603 days). There were no significant differences in technical success, dysphagia palliation, complications (except chest pain) and survival using the two types of stent.

CONCLUSIONS

Self-expanding metal stents are safe with high technical success and achieve satisfactory long-term palliation for dysphagia. The covered Ultraflex and Esophacoil stents are equally effective.

Long-term follow-up of patients after endoscopic sphincterotomy for choledocholithiasis, and risk factors for recurrence

BACKGROUND AND STUDY AIMS

There have been growing concerns about the long-term sequelae of endoscopic sphincterotomy (ES). The aims of the study were to evaluate the long-term clinical outcome of ES for choledocholithiasis and to identify the predictors of recurrence.

PATIENTS AND METHODS

A total of 529 patients (233 men, 296 women; mean age 63, range 9 - 88) who underwent successful ES for choledocholithiasis were evaluated. Follow-up data were obtained retrospectively. Statistical analyses were carried out for 334 patients who had a follow-up of at least 5 years or had recurrence.

RESULTS

Immediate complications occurred in 37 patients (7 %). Follow-up data were available in 458 patients (86.6 %), of whom 280 (61.1 %) were asymptomatic, 127 (27.7 %) died from unrelated causes without recurrence, and 51 (11.1 %) had biliary symptoms and/or choledocholithiasis recurrence. Most recurrences (65 %) occurred more than 2 years following ES and were observed on multiple occasions in 13 patients (2.8 %). A bile duct diameter of 22 mm or greater was found to predict recurrence. Of 190 patients with an intact gallbladder, 11 (5.8 %) developed acute cholecystitis necessitating emergency cholecystectomy; all of these had previously documented gallstones.

CONCLUSIONS

Endoscopic sphincterotomy for choledocholithiasis is found to be safe at long-term follow-up. A dilated bile duct (> or = 22 mm) is a marker for patients at increased risk of recurrence of symptoms and/or choledocholithiasis.

Therapeutic biliary endoscopy

An analysis of the recent medical literature on therapeutic biliary endoscopy shows that the new millennium has already brought several significant developments. However, although advances continue rapidly, several new questions have also arisen, paving the way for further research. Several studies during the last year have also focused attention on cost-effectiveness.

Antagonists of the human CCR5 receptor as anti-HIV-1 agents. Part 3: a proposed pharmacophore model for 1-[N-(methyl)-N-(phenylsulfonyl)amino]-2-(phenyl)-4-[4-(substituted)piperidin-1-yl]butanes

Structure-activity relationship studies directed toward the optimization of (2S)-2-(3-chlorophenyl)-1-[N-(methyl)-N-(phenylsulfonyl)amino]-4-[4-(substituted)piperidin-1-yl]butanes as CCR5 antagonists resulted in the synthesis of the spiro-indanone derivative 8c (IC50=5 nM). These and previous results are summarized in a proposed pharmacophore model for this class of CCR5 antagonist.

Primary prophylaxis of variceal bleeding in liver cirrhosis: failure to learn from past experience

In patients with cirrhosis of liver, variceal bleeding is the most serious complication, with a mortality of up to 50%. Primary prophylaxis of variceal bleeding with shunt surgery or endoscopic variceal sclerotherapy was attempted and then abandoned, as higher rates of complications and mortality were observed. Endoscopic variceal ligation is now being recommended for primary prophylaxis in some centers, as it has fewer complications than sclerotherapy. But this has been done with inadequate evaluation of the cost-effectiveness of variceal ligation. Propranolol therapy is also being widely used for a selected group of patients (large varices with cherry red spots), despite its several limitations and side effects, to reduce frequency of bleeding but without improving survival. Is primary prophylaxis of variceal bleeding cost-effective? The cost involved needs to be accurately assessed in different countries.

Photodynamic therapy: a case series demonstrating its role in patients receiving mechanical ventilation

Photodynamic therapy (PDT) has long been used to treat cancers within the tracheobronchial tree. There have been many reports about the use of PDT for the treatment of carcinoma in situ and for obstructive endobronchial lesions. PDT has not been previously reported in patients receiving mechanical ventilation. PDT offers the advantages of a relatively short duration of treatment, a low side effect profile, and relatively low risk when compared to Nd-YAG laser in patients receiving mechanical ventilation. We report the first successful use of PDT to wean patients from mechanical ventilation.

Effect of cold pressor test and a high-chilli diet on rectosigmoid motility in irritable bowel syndrome

AIM

Visceral hypersensitivity characterizes the irritable bowel syndrome (IBS). We evaluated the effect of a cold pressor test (CPT)--hand immersion in ice water for 1 minute, which evokes a sympathetic response--on rectosigmoid motility in patients with IBS and normal volunteers. Since many Indian patients with IBS complain of worsening of symptoms following a spicy meal, we also evaluated whether a high-chilli diet affects symptoms or changes rectosigmoid motility.

METHODS

Fifteen men with IBS and 13 normal volunteers (all men) were studied. Baseline rectosigmoid manometry was done for 2 h, i.e., 1 h pre- and 1 h post-CPT. The subjects were then kept in hospital on a regular diet (approximately 5 g chilli daily) for 3 days, following which symptoms were reassessed and manometry repeated for 1 h. This was followed by a high-chilli diet (approximately 15 g/day) for 3 days, after which symptoms were reassessed and manometry repeated for 1 h.

RESULTS

There was no difference in the baseline study in the pre-CPT period between patients and control subjects. CPT did not change rectosigmoid motility in either group. IBS patients had varied effect on symptoms but no change in rectosigmoid motility after the high-chilli diet. In the normal volunteers, there was increased activity in the low rectum after the high-chilli diet.

CONCLUSIONS

Cold pressor test does not affect rectosigmoid motility in patients with IBS or normal subjects. A high-chilli diet has varied effect on symptoms in patients with IBS and does not affect rectosigmoid motility.

Substituted 2-aminopyridines as inhibitors of nitric oxide synthases

A series of substituted 2-aminopyridines was prepared and evaluated as inhibitors of human nitric oxide synthases (NOS). 4,6-Disubstitution enhanced both potency and specificity for the inducible NOS with the most potent compound having an IC50 of 28 nM.

Effect of acute and long-term oral tobacco use on oesophageal motility

BACKGROUND AND AIMS

Nicotine administration is known to decrease lower oesophageal sphincter (LOS) pressure. Although a few studies have assessed the effect of tobacco on the LOS, the effect of acute and long-term oral tobacco use on oesophageal motility is not known. The study was designed to investigate the effect of acute and long-term oral tobacco use on LOS and distal oesophageal motility.

METHODS

Thirty-six healthy men (aged 18-65 years, median 34 years; 18 oral tobacco users, 18 non-tobacco users) underwent oesophageal manometry using a water-perfusion system. After baseline manometry, tobacco users were asked to keep 0.5 g tobacco in their mouth for 10 min; non-users of tobacco were kept in quiet surroundings for a similar period. Manometry was then repeated.

RESULTS

The LOS basal pressures were similar in tobacco users and non-tobacco users (mean +/- SD 15.4 +/- 6.3 vs 13.4 +/- 5.3 mmHg). In the distal oesophageal body, the velocity (4.4 +/- 3.1 vs 4.9 +/- 2.6 cm/s), amplitude (92.7 +/- 38.3 vs 84.8 +/- 33.2 mmHg) and duration of contraction (2.1 +/- 0.7 vs 1.7 +/- 0.9 s) were similar in tobacco users and non-users. Acute tobacco use did not affect these parameters. The numbers of abnormal waves (triple peaks and non-transmitted contractions) were also similar in the two groups.

CONCLUSION

Oral tobacco use does not appear to affect LOS pressures and distal oesophageal motility acutely or in the long term.

Jejunal stricture complicating acute mesenteric venous thrombosis secondary to protein C deficiency and factor V Leiden gene mutation

We report a patient with high small intestinal obstruction due to ischemic stricture, secondary to acute mesenteric venous thrombosis. Tests done for hypercoagulability revealed dual etiology (protein C deficiency and factor V Leiden gene mutation). The patient underwent surgical resection and has been on anticoagulation treatment. At 2 years' follow up, she remains asymptomatic.

Acute lymphoblastic leukemia presenting with severe jaundice in an adult

We report an adult patient of acute lymphoblastic leukemia presenting with liver dysfunction.

L-tryptophan urea amides as NK1/NK2 dual antagonists

We report that a systematic modification of an NK1 receptor selective antagonist resulted in the identification of novel compounds, 4c and 4d, with high affinity for both NK1 and NK2 receptors.

Structural requirements for human inducible nitric oxide synthase substrates and substrate analogue inhibitors

Inducible nitric oxide synthase (iNOS; EC 1.14.13.39) catalyzes the NADPH-dependent oxidation of one of the free guanidino nitrogens of L-Arg to form nitric oxide and L-citrulline. Analogues of L-Arg and the inhibitor, L-N6-(1-iminoethyl)lysine, were used to define structural elements required for the binding and catalysis of compounds. L-Arg analogues with sequentially shorter methylene spacing between the guanidino group and the amino acid portion of the molecule were not iNOS substrates but were reversible inhibitors. L-Arg analogues such as agmatine with a hydroxyl substitution at the 2-amino position were substrates. Desaminoarginine was not a substrate but a reversible inhibitor. Desaminoarginine, agmatine, and argininic acid bound to the enzyme to give type I difference spectra similar to that of L-Arg. The amidino compounds L-N6-(1-iminoethyl)lysine, L-N5-(1-iminoethyl)ornithine, and N5-(1-iminoethyl)cadaverdine, but not N6-(1-iminoethyl)-6-aminocaproic acid, were NADPH-dependent, irreversible inactivators of iNOS. For both the L-Arg and L-N6-(1-iminoethyl)lysine analogues, the 2-amino group appeared to play an important role in catalytic events leading to either substrate turnover or mechanism-based inactivation. Inactivation of iNOS by L-N6-(1-iminoethyl)lysine was NADPH- and dioxygen-dependent, but low incorporation of radiolabel with DL--4, 5-3H]-N6-(1-iminoethyl)lysine indicates that the mechanism of enzyme inactivation is not covalent modification of the protein.

Prevalence of hepatitis C virus (HCV) infection in Mumbai

A study was carried out to determine the prevalence of Hepatitis C virus (HCV) in Mumbai among certain high risk groups such as renal transplant recipients, multitransfused and haemodialysis patients; professional and voluntary blood donors and viral hepatitis cases for comparison. Repeated testing of 602 subjects for antibodies to HCV using a second generation ELISA assay (Abbott, USA) showed an overall prevalence of 16.9%. We found 36.4% of multitransfused patients, 27.8% of renal failure cases and 26.2% of renal transplant recipients to be seropositive. Voluntary blood donors in our series showed a surprisingly high prevalence of 15.9%, and this group needs further investigation. Fifty-six of these sera (of which 45 were anti-HCV positive) were tested for HCV RNA by PCR and 14(31.1%) of the seropositive samples were also HCV RNA positive. The present investigation not only shows a high prevalence of HCV in the study groups but also proves the presence of HCV genomes in a significant proportion.