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Context: BRAF mutation has been extensively studied and associated with various tumors. Targeted therapeutic intervention against BRAF mutation is established modality against many such tumors. Various studies have estimated that the prevalence of BRAF mutation in colorectal carcinoma (CRC) is 5%–25%. Considering epidemiology differences from Western population and paucity of studies on BRAF mutation in CRC in Asian patients, the present study was done to study the BRAF mutation in CRC in Indian population. Aims: The aim is to study the distribution of BRAF mutation and its correlation with the American Joint Committee on Cancer (AJCC) stage, grade, and other clinicopathological parameters in CRC. Settings and Design: This was a cross-sectional study. Subjects and Methods: Immunohistochemistry study was done using BRAFV600E monoclonal antibody (Clone VE1) for 65 consecutive cases of CRC in a tertiary care center. The results were statistically analyzed using SPSS version 2.0. Results: This study found that BRAF mutation is not significantly present in CRC as only 4.6% of cases were positive for BRAFV600E mutation. However, there was statistically significant relation between increasing AJCC stage and BRAF mutation. Conclusions: This study concluded that BRAF mutation is not prevalent in Indian population with CRC. However, it is significantly related with advanced AJCC stages.

Context: Lymphangiogenesis correlates with poor prognosis in Invasive Ductal Carcinoma (IDC) breast. D2-40 antibody, a specific marker for lymphatic endothelium, differentiates lymphatic from vascular endothelium. Therefore, the aims of this study were to estimate lymphangiogenesis using D2-40 antibody and correlate with lymphatic invasion (LI) and axillary lymph node (LN) status and compare lymphatic mean vessel density (LMVD) with Tumor (T) and Node (N) stages and grade of tumor. Methods and Material: The study was conducted on fifty consecutive cases of IDC breast who underwent modified radical mastectomy (MRM) from Jan 2009 to March 2011. Hematoxylin-eosin sections and Immunohistochemistry (IHC) slides were studied along with their LN status. LMVD was counted after D2-40 immunostaining (100x magnification) in three hot spots in peritumoral areas and averaged. LI as opposed to vascular invasion (BVI), and LN status for all cases were assessed. Statistical Analysis: Statistical analysis was done using SPSS software (version 14.0 for Windows). Pearson's correlations, χ2 tests and Mann-Whitney U test were used. Results: Lymphangiogenesis varied from 0 to 58 with mean LMVD of 11. Of 50 cases, five showed no lymphatic vessels in peritumoral areas; of these five, three had positive LNs. 21/50 cases had LI. No statistical significant association was seen between lymphangiogenesis and LI. 34/50 cases had positive LNs. Mean LMVD was higher in patients with N2/N3 stage as compared to N0/N1 stage and was statistically significant (P = 0.013). Conclusions: D2-40 is specific marker for lymphatic endothelium. LI and lymphangiogenesis, as opposed to BVI, are better prognostic indicators in IDC breast.

Modifications of microvascular configuration are essential features encountered during the progression of breast tumors. Our objectives were to correlate morphometrically evaluated microvessel parameters (microvessel density [MVD], microvessel caliber [VC], microvessel cross-sectional area [VCSA], percentage of total VCSA [%TVCSA], and total microvessel boundary density [TVBD]) with histologic grades of invasive ductal carcinoma (IDC) of the breast and benign breast lesions. Sixty cases of IDC presented with modified radical mastectomy, and 20 benign breast fibroadenomas were evaluated for various microvessel parameters, using CD34-immunostained histologic sections by computerized image morphometry. Samples were divided into 4 histologic groups: benign, grade 1, grade 2, and grade 3; mean with SD and range was evaluated for each group. Histologic grades showed a strong positive correlation with %TVCSA (ρ=0.773) and TVBD (ρ=0.811) and a moderate positive correlation with MVD (ρ=0.607), VC (ρ=0.609), and VCSA (ρ=0.616) when analyzed for all samples of the 4 groups. Except MVD, all parameters including age was the lowest (P.001) for the benign group. Among the IDCs, differences of mean VC and VCSA were not significant; MVD, %TVCSA, and TVBD were the lowest in grade 1 and the highest in grade 3. Upper cutoff value of benign lesions for MVD was 155mm

Aim: This study was conducted to clinically evaluate the effect of low-level laser therapy (LLLT) as a method of reducing pain reported by patients after placement of their first orthodontic archwires. Materials and methods: A sample of 10 patients with an age group of 12 to 26 years with moderate-to-severe anterior crowding was selected. Each patient was assigned to an experimental group (left quadrant with laser therapy) and a control group (right quadrant with no laser therapy). Low-level laser therapy was given immediately after the placement of initial archwire. All patients were instructed to fill up a survey form at home over the next 7 days. Results: The results revealed that the average onset of pain in the experimental group (16.10 hours) was significantly reduced when compared with the control group (3.10 hours). The most painful day was similar for both the groups. The pain ceased much sooner in the experimental group than in the control group. The intensity of pain was lesser in the experimental group when compared with the control group. Conclusion: Low-level laser therapy was an effective and noninvasive method for controlling pain in orthodontic patients after receiving their first archwires. The duration and intensity of pain reduced with the application of LLLT Clinical significance: Pain reduction during orthodontic procedures. Keywords: Low-level laser therapy, Nickel-titanium wires, Orthodontic pain.

In epilepsy management, control of seizures is the prime objective. However, the quality of life is affected by comorbid conditions that include the neurological, neuropsychiatric, and neurobehavioural disorders. These are not only reactive processes to a chronic condition but also have a bidirectional relationship, sharing common underlying pathogenesis. This article besides addressing these issues also explores the therapeutic management. A systematic search of PubMed from Jan 2006 to August 2016 was undertaken using the terms "comorbidities" and "epilepsy." In addition, articles specifically from India and other original papers were selected based on relevance. In this review, the neuropsychiatric, neurobehavioral (mood disorders, behaviour issues, attention deficits, psychosis), and neurologic [cognitive impairment, migraine, SUDEP-Sudden unexpected death in epilepsy (SUDEP)] comorbidities are covered in relation to epilepsy and its treatment. The incidental disorders such as hypertension, diabetes, and cancer that are mentioned in some reports have not been addressed here. Comorbidities in epilepsy are common but poorly understood and often remain unaddressed. The prevalence of comorbid conditions is considerably higher in epilepsy than seen in the general population and other chronic conditions. There is a wide spectrum of secondary disorders that have a marked impact and significantly increase the burden of the primary epilepsy condition. There is a need to acknowledge, screen, and intervene early in newly diagnosed cases for the optimal management of epilepsy.

SummaryObjective Endocrine diagnosis relies on a thorough history, examination and confirmatory biochemical tests. Previously, in our unit, tests were performed after new patients attended clinic. We proposed that diagnosis and management would be improved if this system was inverted. Design Clinicians and chemical pathologists reviewed available guidance and local practice to determine the key tests to confirm or refute most common endocrine disorders. A system was developed for clinicians to categorize new referrals into diagnostic groups: for example, nodular thyroid disease or possible polycystic ovarian syndrome. Standard letters were developed and sent to patients explaining the requirement for tests to be performed prior to first hospital appointment. The letters and requests for investigation sets were standardized for each diagnostic group and generated via a one-click automated method. After one year, clinical outcomes were audited and patients and staff surveyed. Results The time from referral to confirming diagnosis and starting treatment was halved: mean 11·8–5·7 weeks (P

Renal Involvement in scleroderma is a known problem and the manifestations are well described. Renal involvement in systemic lupus erythematosus (SLE) is also well known. However, in scleroderma and SLE overlap syndrome, the renal findings may vary being a combination of features of immune complex mediated glomerulonephritis as well as thrombotic microangiopathy. We report a case in which the renal manifestation in such a situation was of a focal necrotising pauci-immune glomerulonephritis with crescents, anti-neutrophil cytoplasmic antibody negative. To the best of our knowledge, such manifestations have not been described before. Renal dysfunction in a normotensive setting in such a case should direct one towards evaluation for other causes and should prompt a kidney biopsy. This would be valuable in delineating the pathological process in the kidney and would help in guiding therapy.

Background: An increase in number of melanocytes in the basal cell layer of the epidermis is an important feature in many disorders of hyperpigmentation. In this study, we attempted an objective evaluation of the linear density of melanocytes and keratinocytes, along with other epidermal characteristics, in periorbital hyperpigmentation using immunohistochemistry and morphometric techniques. Methods: Melanocytes and epidermal parameters were assessed by digital morphometry in 30 newly diagnosed cases of periorbital hyperpigmentation and 14 controls from the post-auricular region. Melanocytes were labelled with the immunohistochemical stains, Melan-A and tyrosinase. We studied the linear keratinocyte density, mean linear melanocyte density, ratio of melanocytes to keratinocytes, the ratio between inner and outer epidermal length, maximum epidermal thickness and minimum epidermal thickness. Results: Melan-A expression of melanocytes showed strong positive correlation (r = 0.883) with the tyrosinase expression. Mean linear melanocyte density was 24/mm (range: 13–30/mm) in cases and 17/mm (13–21/mm) in controls and this difference was statistically significant (P < 0.001). The mean ratio of melanocyte to keratinocyte was 0.22 (0.12–0.29) in cases and 0.16 (0.12–0.21) in controls; again, this difference was statistically significant (P < 0.001). There was a mild negative correlation with linear keratinocyte density (r = −0.302) and the ratio between inner and outer epidermal length (r = −0.456). However, there were no differences in epidermal thicknesses. Limitations: There were fewer control biopsies than optimal, and they were not taken from the uninvolved periorbital region. Conclusion: Mean linear melanocyte density and the ratio of melanocytes to keratinocytes is increased in cases with periorbital hyperpigmentation. It is, therefore, likely that increased melanocyte density may be the key factor in the pathogenesis of periorbital hyperpigmentation.

In the present study, we used solution combustion synthesis-bismuth oxide (Bi2O3) as catalyst for the simple and efficient synthesis of 1,2-oxazine based derivatives of 6-fluoro-3-(piperidin-4-yl)benzo[d]isoxazoles, 1-arylpiperazine and carbazoles. (4aR,8aR)-4-(4-Methoxyphenyl)-3-((4-(4-methoxyphenyl)piperazin-1-yl)methyl)-4a,5,6,7,8,8a-hexahydro-4H-benzo[e][1,2]oxazine was found to be the most potent compound with a high degree of selectivity in inhibition towards COX2 (1.7 μM) over COX1 (40.4 μM) demonstrating the significance of 1,2-oxazine derivatives in developing COX2 specific inhibitors. Molecular docking analyses demonstrated that an isoleucine residue in the active site of COX1 is responsible for lower affinity to COX1 and increased potency towards COX2. Overall, our study reveals that the new 1,2-oxazine-based small molecules qualify as lead structures in developing COX2-specific inhibitors for anti-inflammatory therapy.

Technological advances in radiation beam planning and linear accelerator based radiation delivery have led to the development of three dimensional conformal radiation therapy (3D-CRT). The 3D-CRT clinical treatment in our hospital was started in September 1998 and till December 2002, 51 patients with M0 stage prostate carcinoma were treated. Treatment method consisted of pelvis and leg immobilization, planning CT scan, marking of planning target volume and organs at risk and 3D beam plan using multileaf collimated beam shaping through beam′s eye view display. Network controlled 3D conformal radiation therapy was delivered with portal image verification. The median 3D-CRT dose was 72 Gy. Of the 51 patients, 35 were followed-up till December 2002 (minimum follow-up 2 years) in whom 32 were disease free and 3 had progressive disease. Eleven patients died, 8 of progressive disease, one due to second malignancy and two of intercurrent illness. Five patients were lost for follow up during 0 - 29 months period, after 3D-CRT. The acute rectal reaction (RTOG criteria) in 51 patients was grade 0 in 4, grade I in 31 and grade II in 16. None had greater than grade II rectal toxicity. The late rectal toxicity in 49 patients who had a minimum 6 months follow-up was grade 0 in 41, grade I in 3 and grade II in 5. Our experience suggests that a dose of 72 Gy by 3D-CRT can be safely delivered to the prostate and gastrointestinal tolerance during treatment and follow-up period was excellent.

We report a case of a 45-year-old male patient with intraventricular cystic meningioma located in the left lateral ventricle. He presented with complaints of global headache, progressively increasing loss of memory, and frequent episodes of abnormal behavior, of 1 month duration. At the time of hospital admission, his general and neurological examination was normal. Neuroimaging studies showed a left lateral ventricular enhancing mass, composed of mixed solid and cystic areas. The tumor was completely excised via the anterior transcallosal approach. A histological examination revealed a meningothelial meningioma without any atypia. The aim of this report is to present the occurrence of an intraventricular cystic meningioma.

Summary Background: Most Epstein-Barr virus (EBV) associated lymphoproliferative disorders have high proliferation indices. However, classical Hodgkin's disease (cHD) is heterogeneous, with respect to proliferation index of the Reed-Sternberg cell (RS cell), and EBV association. Hence, we investigated whether cHD with and without EBV-association differ with respect to the proliferation index of the RS cells. Further we investigated whether this would have a bearing on patients survival. Patients and methods: We investigated 110 cases of cHD for: a) EBV association by immunohistochemical demonstration of EBV-latent membrane protein-1 and EBV encoded nuclear RNA 1 by mRNA in situ hybridisation; b) Proliferating cell nuclear antigen (PCNA) expression in the RS cells. Results: EBV association was noted in 86 of 110 cases (78%). Higher PCNA expression (P = 0.004) and younger age (P = 0.001) correlated independently with EBV association. The 10 year relapse free survival (RFS) of EBV+ and EBVpatients were 60% and 44%, respectively (P - 0.03). The 10 year overall survival (OS) of EBV+ and EBV- patients were 85% and 64%, respectively (P = 0.03). EBV association maintained its significant impact on RFS and OS within Cox proportional hazard model. Conclusions: Our study suggests that EBV is likely to confer a higher PCNA expression and also contribute towards maintaining the RS cells of cHD in cell cycle. Hence, RS cells in EBV associated cHD would be more responsive to chemotherapy and radiotherapy associated DNA damage. Thus, EBV-association provides survival advantage to cHD patients treated with standard chemotherapy and radiotherapy protocols.

Recombinant DNA and vaccinia virus (VV) vectors that express envelope (Env) proteins of the human immunodeficiency virus (HIV) have each been prominently utilized in vaccine development. These two vectors (termed DNA-Env and VV-Env) are attractive vaccine candidates due to their abilities to elicit both cytotoxic T-lymphocyte and B-cell responses. Our previous work demonstrated that DNA-Env primed animals, that were relatively unresponsive to DNA-Env boosters, could be immunized with VV-Env to yield more than a 100-fold increase in antibody responses. Here we show: (1) results with an optimized vaccine regimen that primes with DNA-Env, boosts with VV-Env, and re-boosts with purified Env proteins, (2) enhanced responses with 8 rather than 16 week intervals between VV-Env and protein immunizations, and (3) the failure of single Env vaccines to reproducibly elicit responses toward heterologous Env, regardless of the vaccination regimen utilized. Results encourage the use of poly-Env vaccine cocktails administered via DNA/VV/protein regimens in future non-human primate and clinical studies.

9- R -2-Phosphonomethoxypropyl adenine (PMPA) is an acyclic nucleoside phosphonate analog that has demonstrated efficacy against human immunodeficiency virus (HIV). We recently described the synthesis, metabolism, and biological activities of bis(isopropyloxymethylcarbonyl)PMPA [bis(poc)PMPA] as an orally bioavailable prodrug for PMPA. Among a large panel of drug-resistant HIV type 1 variants, only the K65R virus was resistant to PMPA. K65R virus also showed reduced susceptibility to bis(poc)PMPA, although the prodrug could still inhibit these viruses at submicromolar, nontoxic concentrations. Among a panel of seven primary clinical isolates from patients with diverse treatment histories, only one isolate showed reduced susceptibility to PMPA and was found to carry three mutations (M41L, T69N, R73K) in its reverse transcriptase catalytic domain.

2'-beta-Fluoro-2',3'-dideoxyadenosine (F-ddA) is an acid-stable purine dideoxynucleoside analog active against a wide spectrum of human immunodeficiency virus type 1 (HIV-1) and HIV-2 strains in vitro. F-ddA is presently undergoing a phase I clinical trial at the National Cancer Institute. We induced HIV-1 variants resistant to F-ddA by exposing wild-type HIV-1 (HIV-1LAI) to increasing concentrations of F-ddA in vitro. After 18 passages, the virus was fourfold less sensitive to F-ddA than HIV-1LAI. Sequence analyses of the passage 18 virus revealed changes in three amino acids in the reverse transcriptase (RT)-encoding region of the pol gene: P to S at codon 119 (P119S; present in 3 of 13 and 28 of 28 molecular clones before and after F-ddA exposure, respectively), V179D (0 of 13 and 9 of 28, respectively), and L214F (9 of 13 and 28 of 28, respectively). Drug sensitivity assays using recombinant infectious clones confirmed that P119S was directly responsible for the reduced sensitivity of HIV-1 to F-ddA. Various infectious clones with single or multiple amino acid substitutions conferring viral resistance against nucleoside RT inhibitors, including HIV-1 variants with multi-dideoxynucleoside resistance, were generally sensitive to F-ddA. The moderate level of resistance of HIV-1 to F-ddA, together with the lack of conferment of significant cross-resistance by the F-ddA-associated amino acid substitutions, warrants further investigation of F-ddA as a potential antiviral agent for use in treatment of HIV-1 infection.

Introduction Modifications of nuclear morphology in conjunction with alteration in microvascular configuration are essential features encountered during the progression of glial tumors. In order to gain more insight into tumor biology of gliomas, objectives of the study were selected (a) to correlate morphometrically evaluated nuclear parameters [nuclear area (NA), nuclear perimeter (NP), nuclear density (ND), percentage of total nuclear area (%TNA)] and microvessel parameters [microvessel density (MVD), microvessel caliber (VC), microvessel cross sectional area (VCSA), total microvessel boundary density (TVBD), percentage of total VCSA (%TVCSA)] with WHO grading; (b) extend such correlations to the ratio parameters: ratio of MVD to ND (MDV/ND), ratio of TVBD to %TNA (TVBD/%TNA) and ratio of %TVCSA to %TNA (%TVCSA/%TNA); and (c) to correlate microvessel and ratio parameters with NP and ND. Materials and methods A total of thirty gliomas managed at this institute during 2009–2012 were evaluated for various nuclear and microvessel parameters by image morphometry using a computerized digital photomicrograph system. For assessment of microvessel parameters CD34-immunostained sections were used while nuclear morphometry was performed on routine hematoxylin-eosin-stained sections. Appropriate statistical analysis was performed in correlation studies. Results All nuclear morphometric parameters showed strong positive correlation with tumor grades (r > 0.7). In contrast, though all microvessel parameters exhibited positive correlation with grades, the parameters TVBD and %TVCSA showed strong positive correlation. The ratio parameters (MVD/ND) and (TVBD/%TNA) showed negative correlation with grades, whereas (%TVCSA/%TNA) did not exhibit meaningful correlation with grades. Further, while all microvessel parameters showed positive correlation with NP and ND; ratio parameters showed negative correlation with them. Conclusion This study indicates that the parameters related to tumor growth (NA, NP, ND, %TNA), and angiogenesis showed increasing trend with tumor grades simultaneously; whereas the parameters related to supply of nutrients per nucleus showed decreasing trends with tumor grades, nuclear size and nuclear density. Thus, the former accounts for increased cellularity, mitosis, and vascular proliferation, while the latter culminates in tumor necrosis, all of which are essential components for grading of gliomas. The present study will therefore have a vital role as surrogate markers of grading of tumor.

A case-control study (244 cases and 264 controls) was done during 1986-89 on a hospital based population to evaluate the risk factors associated with the etiology of senile cataract. Patentis with age between 40-60 years, visual acuity of 6/9 or less, and presence of lenticular opacity of senile origin were included as cases. Age matched individuals with absence of lenticular opacity made up the controls. Multivariate logistic regression analysis revealed that higher systolic BP and number of meals were significantly (P < 0.05) associated with presence of senile cataract; whereas higher weight, education and income, and utilization of cooking water had a significant protective effect against senile cataract. The present study helps the clinician to understand the possible risk factors associated with the development of senile cataract and could be helpful in designing a intervention strategy in future.

CD43 is a cell surface sialoglycoprotein expressed by most cells of hematopoietic origin, including all T lymphocytes. Elimination of CD43 expression by gene targeting in the CEM T cell line results in its increased homotypic adhesion and binding to HIV-1 gp120. Here we report that the CD43-negative CEM cells show increased susceptibility to HIV-1 infection and increased viral replication compared with the parental CD43+ CEM cell line. Increased HIV-1 replication also was observed in CEM cells with diminished CD43 expression secondary to functional inactivation of a single CD43 allele. The CD43- CEM cells were more susceptible to HIV-1-induced cytopathicity than their CD43+ counterparts. HIV-1 replication also was increased in the CD43- CEM cells after transfection with the infectious HIV molecular clone pNL4-3. These data suggest that factors that diminish CD43 expression on T lymphocytes may enhance their susceptibility to HIV-1 infection.

In this retrospective study an attempt is made to document the stage at initial presentation of prostatic cancer. Of the 142 patients seen, 84% presented in an advanced stage and this explains why radical prostatectomies are rarely done in India. Hence efforts are required to screen the population for early diagnosis of the disease.

An initiative of the National Physicians Alliance, the project titled "Promoting Good Stewardship in Clinical Practice," developed a list of the top 5 activities in primary care for which changes in practice could lead to higher-quality care and better use of finite clinical resources. One of the top 5 recommendations was "Don't do imaging for low back pain within the first 6 weeks unless red flags are present." This article presents data that support this recommendation. We selectively reviewed the literature, including recent reviews, guidelines, and commentaries, on the benefits and risks of routine imaging in low back pain. In particular, we searched PubMed for systematic reviews or meta-analyses published in the past 5 years. We also assessed the cost of spine imaging using data from the National Ambulatory Medical Care Survey. One high-quality systematic review and meta-analysis focused on clinical outcomes in patients with low back pain and found no clinically significant difference in pain or function between those who received immediate lumbar spine imaging vs usual care. Published data also document harms associated with early imaging for low back pain, including patient "labeling," unneeded follow-up tests for incidental findings, irradiation exposure, unnecessary surgery, and significant cost. Routine imaging should not be pursued in acute low back pain. Not imaging patients with acute low back pain will reduce harms and costs, without affecting clinical outcomes.

The acyclic purine nucleoside phosphonates, a newly described class of broad-spectrum antiviral agents, effectively inhibit human immunodeficiency virus type 1 (HIV-1) replication in vitro and in animal AIDS models. 9-(2-Phosphonylmethoxyethyl)adenine (PMEA) is currently being evaluated in clinical trials in patients with AIDS. In this study, we investigated the efficacy of PMEA and a related analog, 9-(2-phosphonylmethoxypropyl)diaminopurine (PMPDAP), against HIV-1 isolates exhibiting various degrees of resistance to zidovudine (azidothymidine [AZT]). HIV isolates highly (approximately 50 to 200-fold) resistant to AZT were found to be about two- to eightfold less susceptible to PMEA. A comparable degree of cross-resistance to PMPDAP, a structurally related analog of PMEA, was also observed. However, the 50% effective dose values of PMEA or PMPDAP against a panel of HIV isolates showing intermediate levels (approximately 8 to 25-fold) of AZT resistance was indistinguishable from the 50% effective dose values of PMEA (0.7 to 1.7 versus 2 microM) or PMPDAP (0.4 to 1.4 versus 0.8 to 1 microM) against HIV isolates from patients who had not previously used AZT. In addition, we were unable to generate PMEA- (or PMPDAP)-resistant HIV-1 variants by > 30 serial passages of the virus in the presence of increasing concentrations of PMEA. Careful analysis of HIV-1 isolates from patients previously treated with AZT for cross-resistance to PMEA are needed to evaluate the significance of these observations.

In this report, we describe a new method to measure intracellular zidovudine triphosphate (ZDV-TP) levels in peripheral blood mononuclear cells (PBMCs) from patients treated with ZDV by utilizing inhibition of human immunodeficiency virus type 1 reverse transcriptase activity by ZDV-TP. Intracellular levels of ZDV-TP were determined with our enzymatic assay in PBMCs isolated from the blood of healthy individuals incubated with different concentrations of labeled ZDV and were validated by high-performance liquid chromatography separation and liquid scintillation counting of the radioactive ZDV-TP. These methods gave virtually identical results over a range of ZDV-TP concentrations from 150 to 900 fmol. ZDV-TP recoveries were over 90%, and the limit of quantitation of ZDV-TP by this method was 20 to 50 fmol. To demonstrate the utility of the method, plasma ZDV and intracellular ZDV-TP concentrations were measured at serial time points over 6 h in 12 human immunodeficiency virus-infected volunteers following a single 100- or 500-mg oral dose of ZDV. Systemic oral clearance rates were similar to those in previous studies with adults but were highly variable (range, 0.86 to 2.75 liters/h/kg of body weight). The area under the plasma concentration versus time curve increased significantly (P < 0.0005) with the dose from a median value of 1.2 mg.h/liter at the lower dose to 4.2 mg.h/liter at the higher dose. Median intracellular ZDV-TP levels ranged from 5 to 57 and 42 to 92 fmol/10(6) cells in volunteers administered 100 and 500 mg of ZDV, respectively. Intracellular ZDV-TP levels rose to a plateau value by 2 h and remained consistent to 6 h. Although the higher dose and higher areas under the curve yielded consistently higher intracellular ZDV-TP levels, systemic pharmacokinetics explains only a modest proportion of the variability in cellular pharmacokinetic. The ZDV-TP bioassay should prove useful in further studies of ZDV metabolism in patient-derived PBMCs at the doses of ZDV currently administered.

Bis(pivaloyloxymethyl) [bis(pom)] derivatives of various acyclic nucleoside phosphonates--9-(2-phosphonylmethoxyethyl)adenine (PMEA), 9-(2-phosphonylmethoxypropyl)adenine (PMPA), and 9-(2-phosphonylmethoxypropyl)diaminopurine (PMPDAP)--were found to exhibit 9- to 23-fold greater antiviral activity than their corresponding unmodified compounds. The cytotoxicity of the bis(pom) analogs was also increased by various degrees, thus altering the therapeutic indexes of these compounds. Metabolic studies using [3H]bis(pom)PMEA and [3H]PMEA as model compounds suggested a > 100-fold increase in the cellular uptake of the bis(pom) derivative and formation of active diphosphorylated metabolite. However, the bis(pom) derivatives were chemically unstable and highly susceptible to serum-mediated hydrolysis, factors which limit their potential utility for intracellular drug delivery.

Gene diversity and genetic structure of tribal populations of Andhra Pradesh, India, have been analyzed under a hierarchical model consisting of five regions of the state, tribes within the regions, and local subpopulations within the tribes. Average gene diversity has been estimated from gene frequency data for 15 polymorphic loci by using nested gene diversity analysis of GST. The intralocation coefficient of gene diversity was estimated at 96% of the total, whereas the intertribal, within—and between—regional gene diversities were found to be only 1.90, 0.95, and 1.43%, respectively. The estimate of gene diversity was higher for loci with higher degrees of polymorphism such as ABO, MN, ESD, and PTC and lower for loci with low-level polymorphism and extreme gene frequencies such as Hb, Tf, PHI, 6PGD, and Hp. The nature of selective preference or neutrality at the loci seems to be important in this respect. Tribes of the plains exhibit the least gene diversity, apparently because of higher gene flow among them. The contribution of loci with intermediate gene frequencies in intertribal and regional gene diversity was found to be higher than for loci with extreme allelic frequencies. These results suggest that the most significant component of variation is between individuals within locations and that variation between local subpopulations is negligible in the genetic structure of a population. Forces like selection, gene flow and drift also influence the diversity depending upon the nature of the locus. © 1993 Wiley-Liss, Inc.

Das and Vincent (1) conclude that mangroves reduced the death toll from storm surge in the Orissa Super Cyclone. However, it is unclear from their analyses whether or not this effect occurs independently over and above that of other variables known to affect inundation by long-period waves, such as distance from the coast and topography (2). Further, Das and Vincent (1) are wrong to equate storm surges with wind-generated storm waves. Storm surges have a period of hours to days (3) and consequently behave more like the tide or a tsunami. An effect of vegetation has never been questioned (2). The drag of vegetation must reduce wave velocity to some degree. More important questions, however, are how much protection vegetation can provide and how this compares with other mitigating factors (2). The results suggest that mangroves offered little protection (1). The correlation coefficient (r = −0.13) between mangrove width and village deaths suggests that mangroves explain less than 2% of the variation in deaths. Clearly, other factors were also important. The study site covers only the northern extreme of the area affected by the cyclone and only 254 of >10,000 deaths occurred here. When the total area is considered, there is clear aggregation of deaths, which were much higher closer to where the storm crossed the coast (Fig. 1). Presumably, village proximity to the storm center or other variables such as distance from the coast and height above sea level were more important than mangroves in determining deaths per village. Indeed, these last two variables are significant whenever included in the models. Why then the emphasis on mangroves when no formal methods of model selection were used (4)?

Bilateral presentation of benign Struma ovarii is rare and has not been reported frequently in published literature. A 70-year-old postmenopausal female presented with progressive ascites, bilateral pleural effusion and elevated CA-125 levels. The contrast-enhanced computed tomography (CECT) of the abdomen and pelvis revealed a heterogenous mass in the left adnexa. These findings were suspicious for an ovarian malignancy. After surgery the diagnosis of non functional, bilateral benign Struma ovarii was made. Struma ovarii is a specialized ovarian teratoma composed predominantly of mature thyroid tissue. It is associated with pleural effusion and ascites (Pseudo-Meigs' syndrome) in 5% of cases. The combination of struma ovarii and elevated CA-125 levels has been reported infrequently. This is a rare case of bilateral benign struma ovarii associated with Pseudo-Meigs' syndrome and elevated CA-125 levels. Surgical excision of the ovarian masses induced immediate resolution of the ascites and pleural effusion and a reduction of the serum CA-125 level.

The human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein is essential for virus entry and the formation of multinucleated giant cells by cell fusion, one of the major virus-induced cytopathic effects. To study the effects of potential fusion inhibitors, a vaccinia virus recombinant expressing the envelope glycoprotein was generated and used to infect HeLa CD4+ cells. Syncytium induction was observed as early as 4 h postinfection and continued until the entire monolayer was fused. The N-terminus of the gp41 subunit of the HIV envelope protein is very hydrophobic, and appears to be involved in virus-induced membrane fusion. We synthesized several oligopeptide analogs of the N-terminal region of gp41 and determined their ability to inhibit HIV-induced cell fusion in CD4+ HeLa cells. A hexapeptide which was identical in amino acid sequence to the N-terminus of gp41 was found to completely inhibit cell fusion, whereas peptides with altered sequences showed reduced inhibitory activity. These peptides had no effect on protein synthesis, processing, or transport to the cell surface, and showed no signs of toxicity to cells even at very high concentrations. These results indicate that oligopeptides which are homologous to the fusion peptide of HIV inhibit virus-induced cytopathology, and should be evaluated further as potential antiviral agents.

The envelope (membrane) glycoprotein of HIV is essential for virus attachment and entry into host cells. Additionally, when expressed on the plasma membrane of infected cells, the envelope protein is responsible for mediating cell-cell fusion which leads to the formation of multinucleated giant cells, one of the major cytopathic effects of HIV infections. The envelope glycoproteins of HIV contain regions that can fold into amphipathic alpha-helixes, and these regions have been suggested to play a role in subunit associations and in virus-induced cell fusion and cytopathic effects of HIV. We therefore tested the possibility that amphipathic helix-containing peptides and proteins may interfere with the HIV amphipathic peptides and inhibit those steps of HIV infection involving membrane fusion. Apolipoprotein A-I, the major protein component of high density lipoprotein, and its amphipathic peptide analogue were found to inhibit cell fusion, both in HIV-1-infected T cells and in recombinant vaccinia-virus-infected CD4+ HeLa cells expressing HIV envelope protein on their surfaces. The amphipathic peptides inhibited the infectivity of HIV-1. The inhibitory effects were manifest when the virus, but not cells, was pretreated with the peptides. Also, a reduction in HIV-induced cell killing was observed when virus-infected cell cultures were maintained in presence of amphipathic peptides. These results have potential implications for HIV biology and therapy.

The diagnosis of polio dependents on culturing the virus in stool samples of children with AFP. Using data obtained under the "Right to Information Act" of instances where only one of the two samples was positive for polio, it was possible to estimate the sensitivity of the system to detect cases of polio. The calculations suggest that there were 1625 (95% CI 1528 to 1725) cases of polio in India in 2006 rather than the 674 reported widely!

Rectal injuries diagnosed during radical prostatectomy are readily treated with primary closure and omental interposition. However, once this fails and a fistula develops, the treatment gets more complex. Various surgeries have been described to manage these fistulae, but these are not done frequently and require a great deal of expertise. We report a patient with post-radical prostatectomy rectourethral fistula, treated with cyanoacrylate glue injected through a colonoscope as the fistulous tract was well visualized per rectum. The patient is voiding well per urethra with no rectal leakage 3 months post-catheter removal. Thus, use of cyanoacrylate glue as a minimally invasive non-surgical technique for management of rectourethral fistula appears to be a good option which can be tried before embarking on major surgery.

In India general surgical pathologists report on all tissue types, and subspecialty training is an exception. We undertook an internal audit of gastric biopsy reporting in a large teaching hospital to assess need for subspecialty training. In a first phase, 228 consecutive gastric biopsies (two antral + one body bits in each) undertaken in our institution over six months were objectively evaluated by three experienced histopathologists, based on the updated Sydney classification.1 The three histopathologists were “trained” over four to five sessions at a multihead microscope, each session lasting 20 to 30 minutes (less than two hours cumulative time). Thereafter each …

The value of polythene film ('cling wrap') to improve thermal control and reduce postnatal weight loss in preterm, very low-birthweight babies was investigated.Consecutively born babies with birthweights between 750 and 1500 g were stratified by birthweight (1250 g, 1251-1500 g) and randomised either to the cling wrap (CW) or no cling wrap (NCW) group. The baby bassinette of the RW was covered with cling wrap up to the level of the neck in the CW group for the 1st 7 days. The primary outcome variables were the incidence of hypothermia (axillary temperatureor = 36 degrees C) after initial stabilisation during the first 7 days and cumulative weight loss (percentage of birthweight) at 48 hours of age.Of 51 babies, 26 were randomised to the CW and 25 to the NCW group. None of the babies in the CW group developed hypothermia in the 1st 7 days but 36% in the NCW group (p = 0.001) did. Babies who were hypothermic on admission took less time to reach normal temperature in the CW group. Cumulative weight loss in the 1st 48 hours was 5.0 + 5.6% in the CW group and 8.6 + 7.0% in the NCW group (p = 0.06).Use of CW might be a simple method of maintaining temperature in very low-birthweight babies in developing countries.

A novel fusion protein system based on the highly soluble heme-binding domain of cytochrome $b_5$ has been designed. The ability of cytochrome $b_5$ to increase the levels of expression and solubility of target proteins has been tested by expressing several proteins and peptides, viz., $\alpha$ hemoglobin stabilizing protein, the regulatory subunits of acetohydroxy acid synthase I (ilvM) and II (ilvN), the carboxy terminal domains of mouse neuronal kinesin and pantothenate synthatase, two peptide toxins from cone snails, and the inactivation gate from the brain voltage gated sodium channel, $Na_V1.2$. The fusion protein system has been designed to incorporate protease cleavage sites for commonly used proteases, viz., enterokinase, Factor Xa, and Tobacco etch virus protease. Accumulation of expressed protein as a function of time may be visually ascertained by the fact that the cells take on a bright red color during the course of induction. In all the cases tested so far, the fusion protein accumulates in the soluble fraction to high levels. A novel puriWcation protocol has been designed to purify the fusion proteins using metal aYnity chromatography, without the need of a hexahistidine-tag. Mass spectral analysis has shown that the fusion proteins are of full length. CD studies have shown that the solubilized fusion proteins are structured. The proteins of interest may be cleaved from the parent protein by either chemical or enzymatic means. The results presented here demonstrate the versatility of the cytochrome $b_5$ based fusion system for the production of peptides and small proteins (

A critical goal of HIV vaccine development is the identification of safe and immunogenic vectors. Recombinant vaccinia virus is a highly effective vaccine vector, with demonstrated capacity to protect animals from various viral pathogens, including rabies. Unlike many other candidate vaccine vectors, vast human experience exists with the parenteral smallpox vaccine. However, consideration of recombinant vaccinia virus as a modern vaccine is complicated by the relatively high prevalence of immunocompromised persons compared to such prevalence 4 or more decades ago (when smallpox vaccination was still routine). Administering vaccine by the subcutaneous (SQ) route, rather than the traditional scarification route, could address these concerns. SQ administration could prevent transmission of vaccinia virus to potentially vulnerable persons; it could also avoid the most common adverse events, which are cutaneous in nature. However, previous studies suggest that elicitation of immune response against passenger gene products following SQ administration requires development of a superficial pox lesion, defeating the intention of SQ administration. This is the first report to demonstrate that SQ administration of recombinant vaccinia virus does elicit immune response to the passenger protein in the absence of a cutaneous pox lesion. Results further show that a multi-envelope HIV vaccine can elicit antibody responses toward heterologous HIV-1 not represented by primary sequence in the vaccine. These findings have global implications because they support the consideration of recombinant vaccinia virus as a valuable HIV vaccine vector system.

To retrospectively review the clinical data from patients undergoing radical cystectomy for bladder cancer, and to analyse the complications and survival rates associated with this operation in a developing country.The study comprised 105 patients who underwent radical cystectomy from 1986 to 1993. Data were collected from retrospective reviews of hospital and physician's office records, and by contact with the patients. Metastatic status was evaluated before surgery and tumours staged using the Tumour-Nodes-Metastasis classification. The indication for surgery was histologically confirmed muscle invasion after transurethral resection biopsy, or endoscopically uncontrollable superficial disease. The data were analysed to assess the perioperative complications and long-term survival, with 5-year survival rates determined using Kaplan-Meier survival curves.The complication rate was 27.6%; most of the complications were managed conservatively with good results and re-operation was required in only two patients. There were two deaths (1.9%) at 15-45 days after surgery, but none during surgery. Patients were divided into node-negative and node-positive groups for analysis and 5-year survival rates determined; for node-negative organ-confined disease (or =pT3A) the survival was 68% and for nonorgan-confined disease (or =pT3B) 25%. The 5-year survival rate in the presence of nodal metastases was 13% for N1 and none for N2 disease. Six patients developed urethral recurrence, detected on follow-up urethral-wash cytology. Five of these patients underwent urethrectomy, and four of the six survived for 5 years. Pelvic recurrence occurred in five patients (4.7%), none of whom survived for 5 years.Radical cystectomy and pelvic lymph node dissection remains the mainstay of treatment in muscle-invasive bladder cancer. This is a relatively safe procedure with minimal morbidity and mortality; 68% of the present patients with organ-confined disease survived 5 years and 12 patients were alive at 10 years, indicating the effectiveness of this operation in selected cases. However,29% of patients with nonorgan-confined and nodal metastatic disease survived 5 years, thereby implying the need for more effective adjuvant therapy in these patients. Radical cystectomy is a viable option in developing countries, with 5-year survival rates comparable with most large published series.

Prediction of mortality by application of Pediatric Risk of Mortality (PRISM) score in Pediatric Intensive Care Unit (PICU) patients under Indian circumstances.Prospective study.PICU of a tertiary care multi-specialty hospital.100 sick pediatric patients admitted consecutively in PICU were taken for this study. PRISM score was calculated. Hospital outcome was recorded as (died/survived). The predicted death was calculated by the formula:Of 100 patients, 18 died and 82 survived. By PRISM score 49 children had the score of 1-9. The expected death in this group was 10.3% (n = 5.03) and the observed death was 8.2% (n = 4). Among 45 children with the score of 10-19, the expected mortality was 21.2% (n = 9.6) and observed was 24.4% (n = 11). There were 3 patients with the score of 20-29, the expected mortality in this group was 39.3% (n = 1.18) and observed mortality 33.3% (n = 1). There were 3 patients with scoreor = 30, observed death 66.3% (n = 2) and expected mortality was 74.7% (n = 2.24). There was no significant difference between expected and observed mortality in any group. (p0.5). ROC analysis showed area under the curve of 72%.PRISM score has good predictive value in assessing the probability of mortality in relation to children admitted to a PICU under Indian circumstances.

The objective of the study is to identify the clinical profile of endosulfan poisoning and also to recognise any biochemical parameters which indicate clinical or subclinical dysfunction of organs so that the offending agent can be easily identified in a given case of poisoning and appropriate treatment instituted promptly.Forty four individuals who consumed food which was accidentally contaminated by endosulfan in a rural area were the subjects of the present study. Except the one who died, rest 43 were examined by the authors. A details history, regarding the item of food taken and quantity consumed was noted. Routine bio-chemical parameters like CBC, blood urea, serum creatinine, serum electrolytes, LFT, S Calcium, S Phosporus, were estimated, in fourteen of the patients who were admitted into this hospital. In seven of the patients who were available for follow up, laboratory parameters which were abnormal initially were repeated.Examination revealed that vital signs were stable. There was no jaundice, central nervous system examination showed varying grades of altered sensorium, normal sized pupils briskly reacting to light, normal oculocephalic reflex. There were no lateralising signs like hemiparesis. Plantars were bilateral extensor. There were no signs of meningeal irritation. Complete blood counts, blood sugar, urea, serum creatinine, serum electrolytes were all normal. Liver function tests in the form of SGPT, SGOT were abnormal. Serum bilirubin levels were normal. The values of SGOT and SGPT returned to normal at the end of six weeks. All patients were treated symptomatically. A postmortem examination carried out on the individual who died due to status epilepticus confirmed that the death was due to asphyxia.Endosulfan poisoning can be suspected by the primary CNS manifestations with or without clinical or laboratory evidence of other organ dysfunction like liver, kidney and muscle.

We have correlated the serum levels of TNF alpha and soluble TNF receptor superfamily members with clinico-pathologic parameters in patients of Hodgkin's disease (HD, N = 26) and non-Hodgkin's lymphoma (NHLs, N = 35). HD patients had significantly higher levels of TNF alpha, sTNFRI, and sTNFRII in serum while NHL patients had significantly higher levels of sTNFRI, sTNFRII, sCD27, and sFas as compared to controls. In NHL patients the levels of sCD27 correlated directly and significantly with the high-stage disease, bone marrow involvement, lymph nodal presentation, and serum LDH levels. Similarly in NHL patients, levels of sFas also correlated directly and significantly with the presence of high stage disease. HD patients with B symptoms had significantly higher levels of sTNFRII.

Summary Background Though Epstein-Barr virus (EBV) has been linked to classical Hodgkin’s disease (cHD), only a proportion of cHD cases show EBV-association. While there has been evidence to suggest a crucial role for EBV in the early phase of cHD evolution, we are unclear whether continued presence of EBV is essential for the maintenance of the neoplasm. We have addressed this issue by investigating the EBV-association in paired samples of cHD obtained at presentation and relapse. Materials and methods We have analysed lymph node biopsy samples from 23 cases of cHD at presentation and relapse. In situ hybridization with EBER-1 probe and immunostaining with anti latent membrane protein-1 (LMP-1) antibody was performed on the paraffin sections. PCR for EBNA 3C gene was performed for EBV subtype analysis on the DNA extracted from paraffin sections. Results EBV-association was documented in both the presentation and relapse samples of 14 cases. One case showed loss of EBV-association at relapse. PCR analysable DNA was obtained from both presentation and relapse samples in four of the EBV-associated cases. The EBNA 3C amplimer corresponded to type A strain of EBV in all the samples. Conclusion Loss of EBV-association between presentation and relapse seen in one case implies a hit and run mechanism in EBV-induced lymphomagenesis. Though EBV may be essential early in the evolution of cHD, it may not be required for maintenance of the neoplastic clone. Our study also brings out a speculation that a proportion of EBV-negative cHD could represent loss of EBV in the tumour prior to clinical presentation. Alternatively, an unidentified lymphotropic virus other than EBV might play a pathogenetic role in EBV-negative cHD.

The distribution of the major subtypes of non-Hodgkin's lymphoma (NHL) differs across geographic regions. This is the first study from India that has incorporated immunophenotypic findings while investigating the distribution of NHL subtypes.All cases diagnosed as NHL between January 1995 and June 1998 in the Department of Pathology and in the Lymphoma Registry, Tata Memorial Hospital, Bombay, were selected for the study. The cases were reviewed by three pathologists and diagnostic problems were discussed by a panel of pathologists with a special interest in lymph node pathology. Of a total of 2831 cases, the diagnosis of NHL was accepted in 2773 cases.B-cell lymphomas formed 79.1% of the NHLs, whereas T-cell lymphomas formed 16.2% of the total. Diffuse large B-cell lymphoma was the most common subtype (34% of all NHLs). Follicular centre-cell lymphomas, B-cell small lymphocytic lymphoma, mantle-cell lymphoma, and marginal zone B-cell lymphomas (including MALT lymphomas) amounted to 12.6%, 5.7%, 3.4%, and 8.2%, respectively. Among the T-cell lymphomas, T-cell lymphoblastic lymphoma, anaplastic large-cell lymphomas of T/null-cell type, and other nodal peripheral T-cell lymphomas accounted for 6%, 4.3%, and 2.9% of all cases, respectively.The distribution of NHL subtypes in India shows important differences with those from the rest of the world. Follicular lymphoma and mantle-cell lymphoma are less common in India compared to Europe and the USA. Peripheral T-cell lymphomas and T/NK-cell lymphomas of nasal and nasal types, which are common in many other Asian countries, are also less prevalent. T-cell lymphoblastic lymphoma and anaplastic large T/null cell lymphoma are more prevalent in India.

Dideoxynucleosides, which are potent inhibitors of HIV reverse transcriptase and other viral DNA polymerases, are a common component of highly active anti-retroviral therapy (HAART) (ref. 1). Six reverse transcriptase inhibitors have been approved for human use: azidothymidine; 2'3'-dideoxycytidine; 2'3'-dideoxyinosine; 2', 3'-didehydro-3'deoxythymidine; 2',3'-dideoxy-3'-thiacytidine; and 4-[2-amino-6-(cyclopropylamino)-9H-purin-9-yl]-2-cyclopentene-1-++ +metha nol. Although drug-resistant HIV strains resulting from genetic mutation have emerged in patients treated with HAART (ref. 1), some patients show signs of drug resistance in the absence of drug-resistant viruses. In our study of alternative or additional mechanisms of resistance operating during antiviral therapy, overexpression and amplification of the MRP4 gene correlated with ATP-dependent efflux of PMEA (9-(2-phosphonylmethoxyethyl)adenine) and azidothymidine monophosphate from cells and, thus, with resistance to these drugs. Overexpression of MRP4 mRNA and MRP4 protein severely impaired the antiviral efficacy of PMEA, azidothymidine and other nucleoside analogs. Increased resistance to PMEA and amplification of the MRP4 gene correlated with enhanced drug efflux; transfer of chromosome 13 containing the amplified MRP4 gene conferred resistance to PMEA. MRP4 is the first transporter, to our knowledge, directly linked to the efflux of nucleoside monophosphate analogs from mammalian cells.

The human immunodeficiency virus type 1 (HIV-1) protease inhibitors (PIs)—saquinavir, ritonavir, nelfinavir, and indinavir—interact with the ABC-type multidrug transporter proteins MDR1 and MRP1 in CEM T-lymphocytic cell lines. Calcein fluorescence was significantly enhanced in MDR1 + CEM/VBL100 and MRP1 + CEM/VM-1-5 cells incubated in the presence of various HIV PIs and calcein acetoxymethyl ester. HIV PIs also enhanced the cytotoxic activity of doxorubicin, a known substrate for MDR1 and MRP1, in both VBL100 and VM-1-5 CEM lines. Saquinavir, ritonavir, and nelfinavir enhanced doxorubicin toxicity in CEM/VBL100 cells by approximately three- to sevenfold. Saquinavir and ritonavir also enhanced doxorubicin toxicity in CEM/VM-1-5 cells. HIV-1 replication was effectively inhibited by the various PIs in all of the cell lines, and the 90% inhibitory concentration for a given compound was comparable between the different cell types. Therefore, overexpression of MDR1 or MRP1 by T lymphocytes is not likely to limit the antiviral efficacy of HIV PI therapy.

The hypoxia-inducible factor 1 complex (HIF-1) is involved in the transcriptional activation of several genes, like erythropoietin and vascular endothelial growth factor, that are responsive to the lack of oxygen. The HIF-1 complex is composed of two b-HLH proteins: HIF-1beta that is constitutively expressed, and HIF-1alpha, that is present only in hypoxic cells. The HIF-1alpha subunit is continuously synthesized and degraded by the ubiquitin-proteasome under oxic conditions. Hypoxia, transition metals, iron chelators, and several antioxidants stabilize the HIF-1alpha protein, allowing the formation of the transcriptionally active HIF-1 complex. The mechanisms of oxygen sensing and the pathways leading to HIF-1alpha stabilization are unclear. Because the involvement of a heme protein oxygen sensor has been postulated, we tested the heme sensor hypothesis by using a luciferase-expressing cell line (B-1), that is highly responsive to hypoxia. Exposure of B-1 cells to carbon monoxide and heme synthesis inhibitors failed to show any effect on the hypoxia responsiveness of these cells, suggesting that heme proteins are not involved in hypoxia sensing. Measurement of iron in recombinantly expressed HIF-1alpha protein revealed that this protein binds iron in vivo. Iron binding was localized to a 129-amino acid peptide between sequences 529 and 658 of the HIF-1alpha protein. Although the exact structure of the iron center has not been yet defined, a 2:1 metal/protein molar ratio suggests a di-iron center, probably similar to the one found in hemerythrin. This finding is compatible with a model where redox reaction may occur directly in the iron center of the HIF-1alpha subunit, affecting its survival in oxic conditions.

Bis(isopropyloxymethylcarbonyl) 9- R -(2-phosphonomethoxypropyl)adenine [bis(POC)PMPA] has been identified as a novel prodrug of PMPA. The anti-human immunodeficiency virus activity of bis(POC)PMPA was >100-fold greater than that of PMPA in both an established T-cell line and primary peripheral blood lymphocytes. This improved efficacy was shown to be due to a rapid intracellular uptake of the prodrug resulting in an increased intracellular accumulation of PMPA diphosphate (PMPApp), the pharmacologically active metabolite. PMPApp levels in bis(POC)PMPA-treated cells exceeded by >1,000-fold the levels seen in cells treated with unmodified PMPA in both resting and activated peripheral blood lymphocytes. Significant differences in the intracellular catabolism of PMPA metabolites were noted between the resting and activated lymphocytes. The half-life for the disappearance of PMPApp, derived from either bis(POC)PMPA or PMPA, was 12 to 15 h in the activated lymphocytes and 33 to 50 h in the resting lymphocytes. This long persistence of PMPApp, particularly in resting lymphocytes, may be unique to the nucleoside phosphonate analogs and indicates that effective levels of the active metabolite can be achieved and maintained with relatively infrequent administration of the parent drug.

PMEA [9-(2-phosphonylmethoxyethyl)adenine] inhibited both HSV-1 and HIV-1 replication in MT-2 and HeLa-CD4 cells. (S)-1-[3-hydroxy-2-(phosphonylmethoxy)propyl]cytosine (HPMPC) inhibited both these viruses in the epithelioid HeLa-CD4 cells, but did not inhibit either virus in the T-lymphocytic MT-2 cells. PMEA and HPMPC are metabolized to their diphosphorylated forms within cells, which then inhibit viral polymerases. We therefore compared the metabolism of PMEA and HPMPC in MT-2 and HeLa CD4 cells. PMEApp formation was efficient in both the cell types, whereas HPMPCpp levels were approximately 3-10 fold lower in MT-2 cells, compared to HeLa-CD4 cells. These results indicate that HPMPC can inhibt HIV replication in the appropriate cell types, and show that differences in their metabolism cannot account entirely for the lack of antiviral efficacy of HPMPC in MT-2 cells.

Spinal cavernous haemangiomas are rare and an intradural extramedullary location is rarer still. We give a detailed report of four such cases with a review of 12 cases reported in the past. The clinical presentation, investigations and treatment are discussed.