Mitochondrial translocation of TFEB regulates complex I and inflammation

TFEB is a master regulator of autophagy, lysosome biogenesis, mitochondrial metabolism, and immunity that works primarily through transcription controlled by cytosol-to-nuclear translocation. Emerging data indicate additional regulatory interactions at the surface of organelles such as lysosomes. Here we show that TFEB has a non-transcriptional role in mitochondria, regulating the electron transport chain complex I to down-modulate inflammation. Proteomics analysis reveals extensive TFEB co-immunoprecipitation with several mitochondrial proteins, whose interactions are disrupted upon infection with S. Typhimurium. High resolution confocal microscopy and biochemistry confirms TFEB localization in the mitochondrial matrix. TFEB translocation depends on a conserved N-terminal TOMM20-binding motif and is enhanced by mTOR inhibition. Within the mitochondria, TFEB and protease LONP1 antagonistically co-regulate complex I, reactive oxygen species and the inflammatory response. Consequently, during infection, lack of TFEB specifically in the mitochondria exacerbates the expression of pro-inflammatory cytokines, contributing to innate immune pathogenesis.

An economic and sustainable approach to transform aluminosilicate-rich solid waste to functionally graded composite foam for high-temperature applications

The present study proposes an economical and effective approach for recycling coal overburden and similar solid wastes to fabricate lightweight and high-strength composite foam with industrial applications. Reaction-generated thermo-foaming technique has been used to develop functionally graded mullite-embedded silicate composite foam in a single step. The developed foams with gradient pores exhibit superior thermo-mechanical properties. In situ-growth of mullite phase within the silicate phase results in better mechanical strength of the foam. They possess bulk density, compressive strength and thermal conductivity in the range of 0.31-1.34 g/cm3, 2.97-15.06 MPa and 0.0843-0.2871 W/(m∙K), respectively. Thermal treatment irreversibly transforms the heavy metals present in the solid waste into stable mineral phases, further inhibiting the leaching of heavy metals from the developed foam. The developed foam with tuneable and gradient microstructure is seen as a potential material for thermal insulation and other applications such as refractories, molten metal and hot flue gas filters.

β2-AR inhibition enhances EGFR antibody efficacy hampering the oxidative stress response machinery

The β2-Adrenergic receptor (β2-ARs) is a cell membrane-spanning G protein-coupled receptors (GPCRs) physiologically involved in stress-related response. In many cancers, the β2-ARs signaling drives the tumor development and transformation, also promoting the resistance to the treatments. In HNSCC cell lines, the β2-AR selective inhibition synergistically amplifies the cytotoxic effect of the MEK 1/2 by affecting the p38/NF-kB oncogenic pathway and contemporary reducing the NRF-2 mediated antioxidant cell response. In this study, we aimed to validate the anti-tumor effect of β2-AR blockade and the synergism with MEK/ERK and EGFR pathway inhibition in a pre-clinical orthotopic mouse model of HNSCC. Interestingly, we found a strong β2-ARs expression in the tumors that were significantly reduced after prolonged treatment with β2-Ars inhibitor (ICI) and EGFR mAb Cetuximab (CTX) in combination. The β2-ARs down-regulation correlated in mice with a significant tumor growth delay, together with the MAPK signaling switch-off caused by the blockade of the MEK/ERK phosphorylation. We also demonstrated that the administration of ICI and CTX in combination unbalanced the cell ROS homeostasis by blocking the NRF-2 nuclear translocation with the relative down-regulation of the antioxidant enzyme expression. Our findings highlighted for the first time, in a pre-clinical in vivo model, the efficacy of the β2-ARs inhibition in the treatment of the HNSCC, remarkably in combination with CTX, which is the standard of care for unresectable HNSCC.

Pharmacokinetics and tissue distribution of florfenicol and florfenicol amine in snubnose pompano (Trachinotus blochii) following oral administration

The present study reports the comparative pharmacokinetic profiles of florfenicol and its metabolite (florfenicol amine, FFA) in Trachinotus blochii under tropical marine conditions (salinity: 35 ± 1.4‰; temperature: 28.8 ± 0.54 °C) following a single in-feed oral administration of the recommended dose (15 mg/Kg). Furthermore, the study investigated the distribution of these two compounds in nine different tissues. The maximum florfenicol concentrations (C_max) in plasma and tissues were observed within five hours (T_max), except for bile. The C_max ranged from 572 to 1954 ng/g or ml and was in the intestine > bile > muscle + skin > liver > gill = heart > plasma > kidney = spleen. The elimination half-life of FFC was significantly slower in the bile (38.25 ± 4.46 h). The AUC tissue/plasma was highest for bile (3.77 ± 0.22), followed by intestine > muscle + skin > heart > liver > kidney = gill = spleen. T_max and t_1/2β were slower, and C_max was lower for FFA than florfenicol in all tissues except C_max of the kidney and bile. FFA t_1/2β was exceptionally slower in the kidney (46.01 ± 8.2 h). Interestingly, reaching an apparent distribution rate of > 0.5 was comparatively faster in the kidney, liver, and gills than in other tissues. The highest apparent metabolic rate was in the kidney (0.95 ± 0.01) and the lowest in plasma (0.41 ± 0.01). The generated data can be applied for formulating efficient therapeutic protocols in T. blochii, a promising mariculture species.

Quasi-static indentation damage mechanics of PU foam core reinforced with fly ash particulate

The fly ash (FA) particulates are used in this study to reinforce the polyurethane foam (PUF) core. The FA particles inclusion improves the mechanical performance of the PUF core under compression by increasing its modulus of elasticity. Low-velocity impacts have damage dynamics that are pretty similar to quasi-static indentation. Consequently, the indentation resistance capability of the PUF core is investigated for three types of indenter nose tips with varied FA wt. Percentages (flat-circular, hemispherical, and conical). The results reveal that the reinforced foam core’s resistance varies with reinforcement percentage under indentation. However, FA reinforcement to PUF does not necessarily improve indentation resistance. The damage mechanism of the PUF core under indentation has been evaluated for each type of indenter. The interaction of crushing, shear, and tear of the damaged surface with the change in indenter nose tip has been explained with 0–20% variation of FA particles. Scanning electron microscope (SEM) images are taken for the analysis of the damaged PUF core cross-section at the indented location. Earlier mechanical findings of the scatter in deformation behavior with the indenter nose tip geometry are substantiated by the SEM studies.

Clinical Profile, Treatment, and Outcome of Patients with Secondary Hemophagocytic Lymphohistiocytosis in Critically Ill Patients: A Prospective Observational Study

Introduction

The objective of the study was to evaluate the clinical profile and outcome of patients with secondary hemophagocytic lymphohistiocytosis (HLH) in critically ill patients.

Materials and methods

A prospective observational study was conducted where critically ill adult patients presenting with fever and bicytopenia were evaluated according to the HLH-2004 diagnostic criteria for the presence of secondary HLH. The underlying trigger, clinical profile, treatment, and outcome of patients with HLH were analyzed.

Results

Of the 76 critically ill patients with fever and bicytopenia, 33 (43%) patients were diagnosed with HLH. The following triggers for HLH were identified: bacterial infections (23%), fungal infections (10%), viral infections (10%), parasitic infections (10%), autoimmune diseases (13%), and malignancy (8%). A total of 78% of the HLH cases received steroids, but the use of steroids was not associated with improvement in mortality.

Conclusion

There is a high prevalence of HLH in patients presenting with fever and bicytopenia in critically ill adult patients. Infections were identified as the most common trigger of HLH.

How to cite this article

Fazal F, Gupta N, Soneja M, Mitra DK, Satpathy G, Panda SK, et al. Clinical Profile, Treatment, and Outcome of Patients with Secondary Hemophagocytic Lymphohistiocytosis in Critically Ill Patients: A Prospective Observational Study. Indian J Crit Care Med 2022;26(5):564–567.

Enhanced exudation of malate in the rhizosphere due to AtALMT1 overexpression in blackgram (Vigna mungo L.) confers increased aluminium tolerance

Worldwide, 50% of soil is acidic, which induces aluminium (Al) toxicity in plants, as the phyto-availability of Al³⁺ increases in acidic soil. Plants responds to Al³⁺ toxicity by exuding organic acids into the rhizosphere. The organic acid responsible for Al³⁺ stress response varies from species to species, which in the case of blackgram (Vigna mungo L.) is citrate. In blackgram, an Arabidopsis malate transporter, AtALMT1, was overexpressed with the motive of inducing enhanced exudation of malate. Transgenics were generated using cotyledon node explants through Agrobacterium tumefaciens-mediated transformation. The putative transgenics were initially screened by AtALMT1-specific genomic DNA PCR, followed by quantitative PCR. Two independent transgenic events were identified and functionally characterized in the T₃ generation. The transgenic lines, Line 1 and 2, showed better root growth, relative water content and chlorophyll content under Al³⁺ stress. Both lines also accounted for less oxidative damage, due to reduced accumulation of ROS molecules. Photosynthetic efficiency, as measured in terms of F_v /F_m , NPQ and Y(II), increased when compared to the wild type (WT). Relative expression of genes (VmSTOP1, VmALS3, VmMATE) responsible for Al³⁺ stress response in blackgram showed that overexpression of a malate transporter did not have any effect on their expression. Malate exudation increased whereas citrate exudation did not show any divergence from the WT. A pot stress assay found that the transgenics showed better adaptation to acidic soil. This report demonstrates that the overexpression of a malate transporter in a non-malate exuding species improves adaptation to Al³⁺ toxicity in acidic soil without effecting its stress response mechanism.

Combined effects of vacuum packaging and mint extract treatment on the biochemical, sensory and microbial changes of chill stored Indian mackerel

The present study was aimed to investigate the combined effects of vacuum packaging and mint extract treatment on the quality changes of gutted Indian mackerel (Rastrelliger kanagurta) during storage at 0-2 °C for 22 days. Biochemical, total viable count and sensory quality of chill stored mackerel were analysed at periodic intervals. Mint extract treated [dipping in 0.5% (w/v) solution of mint extract for 30 min] and vacuum packed fishes (MEVP) had significantly lower total volatile base nitrogen and trimethyl amine nitrogen compared to those packed under vacuum (CVP) and air (CAP) without mint extract treatment. Nucleotide degradation rate was lower in MEVP followed by CVP and CAP. Vacuum packaging in combination with ME treatment significantly inhibited lipid hydrolysis and lipid oxidation in mackerel as observed from its lower free fatty acid, peroxide value and thiobarbituric acid reactive substances values. Synergistic use of mint extract and vacuum packaging has markedly controlled microbial proliferation in the samples. Based on sensory evaluation, shelf life of Indian mackerel stored at 0-2 °C was determined as 13 days for CAP group, 16 days for CVP group and 21 days for MEVP group, respectively. The present study revealed that combination of vacuum packaging and mint extract treatment can be a promising technology to improve the storage quality of chill stored gutted mackerel.

Origin of the Spin-Orbital Liquid State in a Nearly J=0 Iridate Ba_{3}ZnIr_{2}O_{9}

We show using detailed magnetic and thermodynamic studies and theoretical calculations that the ground state of Ba_{3}ZnIr_{2}O_{9} is a realization of a novel spin-orbital liquid state. Our results reveal that Ba_{3}ZnIr_{2}O_{9} with Ir^{5+} (5d^{4}) ions and strong spin-orbit coupling (SOC) arrives very close to the elusive J=0 state but each Ir ion still possesses a weak moment. Ab initio density functional calculations indicate that this moment is developed due to superexchange, mediated by a strong intradimer hopping mechanism. While the Ir spins within the structural Ir_{2}O_{9} dimer are expected to form a spin-orbit singlet state (SOS) with no resultant moment, substantial frustration arising from interdimer exchange interactions induce quantum fluctuations in these possible SOS states favoring a spin-orbital liquid phase down to at least 100 mK.

Observation of S = 1/2 quasi-1D magnetic and magneto-dielectric behavior in a cubic SrCuTe2O6

We investigate the magnetic, thermal, and dielectric properties of SrCuTe2O6, which is isostructural to PbCuTe2O6, a recently found, Cu-based 3D frustrated magnet with a corner-sharing triangular spin network having dominant first and second nearest neighbor (nn) couplings (Koteswararao et al 2014 Phys. Rev. B 90 035141). Although SrCuTe2O6 has a structurally similar spin network, the magnetic data exhibit the characteristic features of a typical quasi-1D magnet, which mainly resulted from the magnetically dominant third nn coupling, uniform chains. The magnetic properties of this system are studied via magnetization (M), heat capacity (C p ), dielectric constant ([Formula: see text]), and measurements along with ab initio band structure calculations. The magnetic susceptibility [Formula: see text] data show a broad maximum at 32 K and the system orders at low temperatures [Formula: see text] K and [Formula: see text] K, respectively. The analysis of the [Formula: see text] data gives an intra-chain coupling, [Formula: see text], to be about  ≈  -  42 K with non-negligible frustrated inter-chain couplings ([Formula: see text] and [Formula: see text]). The hopping parameters obtained from the LDA band structure calculations also suggest the presence of coupled uniform chains. The observation of simultaneous anomalies in [Formula: see text] at [Formula: see text] and [Formula: see text] suggests the presence of a magneto-dielectric effect in SrCuTe2O6. A magnetic phase diagram is also built based on the M, C p , and [Formula: see text] results.

Epidemiological study of canine parvovirus infection in and around Bhubaneswar, Odisha, India

Aim:

An epidemiological study of canine parvovirus infection in dogs in and around Bhubaneswar, Odisha was conducted between December 2012 to March 2013 and prevalence rate was studied on the basis of age, breed, and sex.

Materials and Methods:

A total of 71 fecal samples from suspected diarrheic dogs were collected in sterile phosphate buffer saline (10% W/V) and examined by polymerase chain reaction (PCR) for detection of canine parvo virus infection, followed by epidemiological study in relation to age, breed, and sex.

Results:

Of 71 samples analyzed, 29 (40.85%) were found to be positive by PCR assay. The infection was higher in Deshi/local breeds (34.48%), followed by German shepherd (17.24%), equal incidences in mixed and Labrador retriever (10.34%), Rottweiler and German spitz showed 6.90% each and finally lower incidences in four breeds (3.45%) such as Dalmatians, Nea politan mastiff, Pug and Great Dane. Age-wise prevalence study revealed the infection being more in the age group of 3-6 months (41.37%), followed by equal incidences of 27.59% in 1-3 months and 6-12 months age group, and a low incidence in age groups above 12 months (3.45%). The incidence was predominantly higher in males (86.21%) than females (13.79%).

Conclusions:

The epidemiological analysis revealed that the breed wise prevalence was found to be more in Deshi breeds as compared to others, age groups below 6 months were found to be more prone to parvovirus infection and males were mostly infected.

Development and validation of a stability-indicating RP-HPLC method for estimation of atazanavir sulfate in bulk

A stability-indicating reverse phase–high performance liquid chromatography (RP–HPLC) method was developed and validated for the determination of atazanavir sulfate in tablet dosage forms using C₁₈ column Phenomenix (250 mm×4.6 mm, 5 μm) with a mobile phase consisting of 900 mL of HPLC grade methanol and 100 mL of water of HPLC grade. The pH was adjusted to 3.55 with acetic acid. The mobile phase was sonicated for 10 min and filtered through a 0.45 μm membrane filter at a flow rate of 0.5 mL/min. The detection was carried out at 249 nm and retention time of atazanavir sulfate was found to be 8.323 min. Linearity was observed from 10 to 90 μg/mL (coefficient of determination R² was 0.999) with equation, y=23.427x+37.732. Atazanavir sulfate was subjected to stress conditions including acidic, alkaline, oxidation, photolysis and thermal degradation, and the results showed that it was more sensitive towards acidic degradation. The method was validated as per ICH guidelines.

Assessment of Her-2/neu status using immunocytochemistry and fluorescence in situ hybridization on fine-needle aspiration cytology smears: experience from a tertiary care centre in India

Breast carcinoma shows amplification/overexpression of Her-2/neu in ∼20-30% of cases. The determination of Her-2/neu expression accurately is vital in clinical practice as it has significant predictive value and eligibility for anti Her-2/neu therapy. Amplification and overexpression of Her-2/neu gene is traditionally identified by fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) on tissue sections; only a few studies have evaluated feasibility of these techniques on cytological smears. One hundred cases of breast cancer with fine-needle aspiration cytology (FNAC) samples and corresponding surgically resected specimen were selected. Immunocytochemistry (ICC) and FISH for Her-2/neu was done on FNA smears, whereas IHC was performed on corresponding tissue sections. Diagnostic accuracy of ICC was 99% when compared with IHC. Comparison of FISH results with IHC showed 100% concordance. Unlike many centers in West, FNAC is still routinely performed in developing countries like India where vast majority of breast cancer cases present as palpable lumps. The high rates of accuracy of ICC and FISH for Her-2/neu detection can make FNAC a relevant first line of investigation as a cost effective model with a rapid turn-around time, providing complete information necessary for initial management of breast cancer patients.

NiS--an unusual self-doped, nearly compensated antiferromagnetic metal

NiS, exhibiting a text-book example of a first-order transition with many unusual properties at low temperatures, has been variously described in terms of conflicting descriptions of its ground state during the past several decades. We calculate these physical properties within first-principle approaches based on the density functional theory and conclusively establish that all experimental data can be understood in terms of a rather unusual ground state of NiS that is best described as a self-doped, nearly compensated, antiferromagnetic metal, resolving the age-old controversy. We trace the origin of this novel ground state to the specific details of the crystal structure, band dispersions and a sizable Coulomb interaction strength that is still sub-critical to drive the system in to an insulating state. We also show how the specific antiferromagnetic structure is a consequence of the less-discussed 90° and less than 90° superexchange interactions built in to such crystal structures.

Formulation, in vitro drug release study and anticancer activity of 5-fluorouracil loaded gellan gum microbeads

5-Fluorouracil loaded calcium-zinc-gellan and calcium-zinc-gellan-ethyl cellulose microbeads were successfully prepared by simple ionotropic gelation and oil in water ionotropic gelation technique, respectively. Prepared microbeads were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy and evaluated for particle size, drug content, encapsulation efficiency, drug release and cell cytotoxicity study. Microbeads formed were spherical with rough surface. As concentration of gellan and ethyl cellulose has increased encapsulation efficiency, particle size and sustained drug release effect also increased. The release of 5-fluorouracil from microbeads has followed Hixson Crowell model suggesting the mechanism of drug release as dissolution controlled. Cytotoxicity analysis on HT-29 human colon cancer cell lines indicated that 5-FU loaded gellan gum/gellan in combination with ethyl cellulose microbeads leads to sustained releases of drug and thus delayed apoptosis over a long period of time. The formulation with drug:gellan:ethyl cellulose ratio 2.5:7.5:1 was found to be more effectual in terms of sustained drug release activity in addition to anti-cancer activity.

Extraction of nickel by microbial reduction of lateritic chromite overburden of Sukinda, India

Microbial extraction of nickel from lateritic chromite overburden (COB), Sukinda by Acidithiobacillus ferrooxidans has been investigated in this work. In anoxic environment, A. ferrooxidans reduced the ferric iron in goethite [Fe(O)OH] mineral of COB by using elemental sulphur as electron donor. Nickel embedded in the complex goethite matrix of COB was successfully recovered by cumulative action of sulphuric acid, generated by oxidation of elemental sulphur and reduction of ferric iron in goethite matrix by A. ferrooxidans. Forty one percent of the nickel present in COB was extracted in a 3 L scale bioreactor (pH of 1.8 ± 0.05, temperature of 28 ± 2°C) maintained in anoxic environment. In contrast, only 11% of the nickel present in COB was extracted with continuous supply of air to the bioreactor keeping all the parameters unchanged. Kinetics study of anoxic microbial processing of COB revealed that the chemical reaction rate control model fits to the rate of nickel dissolution (R(2)=0.975).

Antibacterial activity of Croton roxburghii Balak. against the enteric pathogens

In this study, the antibacterial activity of crude (aqueous and alcoholic) extracts of the bark and leaf of Croton roxburghii Balak. (Euphorbiaceae) was tested against enteric pathogens causing urinary tract infection (UTI) using the agar cup method, minimum inhibitory concentration (MIC), time kill kinetics and synergy study. The ethanol extract exhibited a significant and broad spectrum of inhibition as compared to the aqueous extract of both the bark and leaf. The highest antibacterial activity was observed against Staphylococcus aureus followed by enteropathogenic and enterotoxigenic Escherichia coli. The diameter of inhibition zones varied from 10 to 18 mm for both aqueous and alcoholic extracts. The MIC value ranged from 356 to 625 μg/ml. This could justify the traditional use of this plant in dysentery and other infections.

Prediction Models for DNA Transcription Termination Based on SOM Networks

This paper presents two efficient models for predicting transcription termination (TT) in human DNA. A neural network, self-organizing map, was used for finding features from a human polyadenylation (polyA) sites dataset. We derived prediction models related to different polyA signals. A program, "Dragon PolyAtt", for predicting TT regions was designed for the two most frequent polyA sites "AAUAAA" and "AUUAAA". In our tests, Dragon PolyAtt predicts TT regions with a sensitivity of 48.4% (13.6%) and specificity of 74% (79.1%) when searching for polyA signal "AAUAAA" ("AUUAAA"). Both tests were done on human chromosome 21. Results of Dragon PolyAtt system are substantially better than those obtained by the well-known "polyadq" program.

Infantile systemic hyalinosis associated with a putative splice-site mutation in the ANTXR2 gene

Infantile systemic hyalinosis (ISH) is a rare autosomal recessive genetic disorder characterized by dermal and subcutaneous fibromatosis, joint contractures and bone deformities. The condition usually presents at birth, resulting in death in infancy. ISH is caused by mutations in the anthrax toxin receptor 2 gene, ANTXR2, also known as CMG2. We report an Indian child with ISH in whom we identified a homozygous acceptor splice site mutation, IVS2-4G>A. In silico analysis of this sequence showed that it changed predicted cryptic splicing, leading to out-of-frame transcripts and little, if any, functional protein. Mutations in the ANTXR2 gene can also cause juvenile hyaline fibromatosis (JHF). Although there are currently no effective treatments for ISH or JHF, identification of pathogenetic mutations in the ANTXR2 gene makes DNA-based prenatal diagnosis feasible for subsequent pregnancies.

Hepatitis E virus enters liver cells through receptor-dependent clathrin-mediated endocytosis

We investigated the virus-host interaction for hepatitis E virus (HEV) by performing competitive binding assays using in vitro assembled virus-like particles (VLPs). We used Escherichia coli expressed native capsid protein (pORF2) and its mutants with an attached Gly((5))-Ala (linker) reporter [enhanced green fluorescent protein (EGFP)/firefly luciferase (Fluc)]. Transmission electron microscopy and nanoparticle tracking showed near uniform particles of approximately 30-35 nm in diameter for pORF2 VLPs and 60-100 nm for reporter-linked VLPs. Binding of reporter-linked full-length (1-660aa) and N-terminal truncated (Δ1-112aa) pORF2 VLPs to Huh7 cell surfaces was found to be specific with 1.92 ± 0.065 × 10(5) sites per cell. Saturation binding indicated an equilibrium dissociation constant (K(d)) of 121.1 ± 23.83 and 123.8 ± 16.15 nm for pORF2-linker-EGFP and pORF2-linker-Fluc VLPs respectively. A similar binding pattern was observed for Δ1-112aa pORF2-linker-EGFP and Δ1-112aa pORF2-linker-Fluc VLPs with K(d) values of 123.6 ± 10.60 and 135.6 ± 16.19 nm respectively. The affinity (log K(i)) of pORF2 binding on Huh7 cells in the presence of EGFP-tagged and Fluc-tagged pORF2 VLPs was found to be approximately 2.0. However, no VLP formation or binding was observed with refolded C-terminal truncated (Δ458-660aa) pORF2. We investigated HEV internalization using fluorescent VLPs (EGFP-VLPs), which showed vesicle-mediated uptake starting at 5 min post-incubation. The uptake of VLPs could be stopped by inhibitors for clathrin-dependent endocytosis, but not by caveosome inhibitors. No binding and uptake of EGFP-VLPs were observed on non-hepatic cell lines (HeLa and SiHa). These findings suggest that HEV attaches to the host cell via a specific high affinity receptor and enters the cytoplasm by clathrin-mediated endocytosis.

Immunohistochemistry for the diagnosis of hepatitis E virus infection

Hepatitis E virus (HEV) is an emerging pathogen and the most common cause of acute viral hepatitis all over the world. We describe here an immunohistochemical method for the detection of HEV antigens (pORF2 and pORF3) in formalin-fixed, paraffin-embedded liver tissues using monoclonal antibodies raised against two of the virus proteins (pORF2 and pORF3). We analysed their specificity and sensitivity in comparison with serology and nucleic acid detection in cases of acute liver failure (ALF). We used this test on 30 liver biopsies collected post-mortem from the patients of ALF caused by HEV infection. These cases were selected on the basis of positive results for enzyme immunoassay (IgM anti-HEV). Of the 30 cases taken from the archives of the Department of Pathology, the antibodies successfully stained all. However, only 25 serum samples (83.3%) of these were positive for HEV RNA. Fifteen controls used (Five noninfected liver tissues, five HBV- and five hepatitis C virus-infected liver tissues) were all negative. The immunohistochemical assay described here may prove a valuable tool for the detection of HEV infection in biopsy, autopsy and explant liver tissues and can serve as a link along with other available tests to delineate the extent of HEV-associated problem worldwide.

Standardization of sulaharan yoga: an ayurvedic tablet formulation

Quality assurance of herbal products may be ensured by proper quality control of the herbal ingredients and by means of good manufacturing practice. We have developed a simple scheme for the standardization and authentication of Sulaharan Yoga a poly herbal formulation. Sulaharan Yoga was prepared as per Ayurvedic Formulary of India. In-house and marketed preparation has been standardized on the basis of organoleptic characters, physical characteristics and physico-chemical properties. The set parameters were found to be sufficient to standardize the Sulaharan Yoga and can be used as reference standards for the quality control/ quality assurance study.

Study of cellular immune response against Hepatitis E virus (HEV)

Hepatitis E virus infection (HEV) is a major cause of acute viral hepatitis in the developing world. The immunopathology of HEV infections has not yet been elucidated. The virus is noncytopathic, and therefore, liver injury may be attributed to immune-mediated damage by cytotoxic T cells and natural killer cells. Therefore, we studied the nature of immune cells involved in HEV-induced liver damage using immunohistochemistry in liver biopsies taken from patients with HEV-induced acute liver failure and demonstrated a significant infiltration of activated CD8(+) T cells containing granzymes. These findings suggest the possible involvement of cytotoxic T cells in disease pathogenesis during HEV infection.

Synthesis of beta-SiC/SiO2 core-sheath nanowires by CVD technique using Ni as catalyst

Cubic silicon carbide (beta-SiC)/SiO2 nanowires with uniform and knotted-core structures have been synthesized on nickel-coated Si(111) substrates at 1150 degrees C by using hexamethyldisilane (HMDS) as the source material in a hot wall atmospheric pressure chemical vapor deposition (APCVD) system. The nanowires consist of a single crystalline beta-SiC core wrapped with an amorphous SiO2 shell. The as-prepared SiC nanowires and the deposited Ni films were characterized by field emission scanning electron microscopy, X-ray diffraction, high resolution transmission electron microscopy, energy dispersive X-ray spectroscopy, micro-Raman spectroscopy, infrared spectroscopy and atomic force microscopy. The results show that the nanowires are random in direction and have diameter ranges from 25 nm to 70 nm. The core of the nanowires has a cubic zinc blend structure and a high density of planar defects is often found. The twin plane defects are suspected to be the main reason for the formation of the knotted-core SiC nanowires. A possible growth mechanism based on vapor-liquid-solid (VLS) by base growth technique is proposed.

Impact of bottom trawling on sediment characteristics--a study along inshore waters off Veraval coast, India

The present communication is a study on the impact of bottom trawling on the sediment characteristics along Veraval coast, which is the largest trawler port of India. Experimental bottom trawling was conducted from MFV Sagarkripa at five transects of water depths 15-20 m, 21-25 m, 26-30 m, 31-35 m and 36-40 m in commercial trawling grounds. Trawling was conducted for 12 months in a span of 15 months (September 2005-November 2006) excluding the trawl ban period (June to August). The sediment texture was analysed by pipette analysis and organic matter by wet oxidation method. The variations in organic matter and sediment texture were prominent between the stations selected at different depths. The sedimentary organic matter exhibited variations with different water depths and seasons. The organic matter content decreased with depth. Experimental trawling considerably reduced the organic matter content at all depths. Continued and incessant trawling operation can cause even more drastic reductions, where organic matter (OM) content is already very small. The sand proportion showed depth-wise variation; but seasonal and trawling effect was not significant showing highest values at 36-40 m depth. The silt proportion did not exhibit significant depth-wise variation. The seasonal variation of silt was significant whereas trawling effect imparted to silt was not evident. Trawling has no significant effect on clay concentration. But seasonal variation had great influence on the clay distribution and indicated significantly high depth-season interaction. The sediment of the study area was predominant in silt proportion. It was observed that the seasonal/natural variations were more prominent masking the trawling effect on silt.

Immune response to hepatitis B virus surface antigen peptides during HBV infection

Antibody responses of patients with acute (n = 73), fulminant (n = 30) and chronic (n = 51) hepatitis B virus (HBV) infection as well as recovered individuals (n = 7) were studied against three synthetic peptides, Pre-S1 amino acids (aa. 12–32), Pre-S2 amino acids (aa. 120–145), and S amino acids (aa. 124–147) of the envelope region (HBsAg). T cell blastogenic response was investigated in a proportion of the patients (27 acute, nine fulminant, 13 chronic hepatitis and seven recovered individuals) along with seven HBV vaccinated and three normal individuals. The presence of T cell response against S peptide was observed in all the cases (9/9, 100%) during early acute hepatitis. This was suppressed during late stages (8/18, 44%) followed by partial reversal during recovery (5/7, 71 %). T cell response and antibodies to Pre-S1 and Pre-S2 peptides were present only in one-third of the patients throughout these periods. The T cell blastogenic response as well as antibody reactivity against these peptides were absent and minimal in chronic hepatitis. Immune response against envelope protein appears to play a major role in acute hepatic injury due to HBV infection and help in virus clearance.

Clinical relevance of HBV DNA load in patients with chronic hepatitis B infection

BACKGROUND

Hepatitis B virus (HBV) DNA detection and quantification are now playing an increasing role in the assessment of disease activity and response to therapy. However, viraemia levels which define various stages of HBV infection have not yet been established.

AIM

To define viraemia levels which describe various stages of chronic hepatitis B virus infection.

METHODS

In a retrospective study, stored sera samples of chronic hepatitis B virus (CHB) infected patients registered at AIIMS liver clinic, from January 1996 to June 2005 were subjected to competitive, quantitative PCR analysis.

RESULTS

The median HBV DNA load was lowest among carriers and highest among patients with chronic hepatitis B [0 (0-8) vs. 7 (0-12) log10 copies/ml, respectively; p<0.05]. As compared to chronic hepatitis patients the DNA load was also lower among cirrhotics [7 (0-12) vs. 4.5 (0-8) log10 copies/ml, respectively; p<0.05] and hepatocellular cancer patients [ 7(0-12) vs. 0 (0-8) log10 copies/ml, respectively; p<0.05]. Patients with carriers had a DNA load which was significantly lower than e antigen negative CHB [0 (0-8) vs. 6 (0-10) log10 copies/ml; p<0.05] or e antigen positive CHB [0 (0-8) vs 8 (0-12) log10 copies/ml; p<0.05]. A threshold of 3.5 log10 copies/ml had sensitivity and specificity of 83% and 58% respectively in differentiating carriers from e antigen negative CHB. There was a strong positive correlation of HBV DNA load with inflammatory grade (R=0.334; p=0.0001), fibrosis stage (R=0.276; p=0.001) and ALT levels (R=0.378; p=0.0001). 82% (9/11) of those who lost e antigen had a decline in HBV DNA levels to <5 log10 copies/ml, whereas only 12.5% (1/8) of those who did not lose e antigen had a decline in DNA load below this level.

CONCLUSIONS

HBV DNA viraemia levels correlate positively with the inflammatory grade, fibrosis stage and ALT levels. Most patients who loose e antigen have a decline in DNA load to below 5 log10 copies/ml. Further prospective studies employing repeated measurements are required to define a threshold to differentiate between HBV carriers and e antigen negative CHB.

Characterization of Streptococcus pneumoniae ophthalmic, systemic & commensal isolates by pulsed-field gel electrophoresis & ribotyping

BACKGROUND & OBJECTIVE

Streptococcus pneumoniae is common in ocular and systemic infections and is a part of normal nasopharyngeal flora. Very few studies regarding genetic analysis of S. pneumoniae isolates causing eye infections are available. This study was undertaken to do pulse field gel electrophoresis (PFGE) analysis and ribotyping of S. pneumoniae isolates obtained from eye infections, systemic infections and nasopharyngeal flora.

METHODS

Sixty one well characterized S. pneumoniae isolates (38 from ophthalmic infections, 9 from systemic infections and 14 commensals) were characterized using PFGE of the whole genome after SmaI, restriction enzyme digestion and conventional ribotyping using Escherichia coli rRNA operon as the probe. Phylogenetic tree was drawn using unweighted pair group method analysis (UPGMA).

RESULTS

The 38 S. pneumoniae isolates from eye infections belonging to 15 serotypes were placed in to 11 PFGE types and 15 ribotypes. The 9 systemic isolates (7 seotypes) were distributed in 7 PFGE types and 6 ribotypes. The 14 commensal isolates were placed in 11 serotypes, 5 PFGE types and 6 ribotypes. Most of the PFGE types and ribotypes consisting of ocular isolates also contained systemic and commensal isolates.

INTERPRETATION & CONCLUSION

Considerable genetic similarity was observed between the isolates from ocular and systemic infections and those colonized in nasopharynx. PFGE analysis could differentiate majority of the isolates according to site of infections. There was a considerable DNA polymorphism within the studied bacterial population.

Serotype distribution of Streptococcus pneumoniae isolates from ophthalmic and systemic infections and of commensal origin

BACKGROUND AND OBJECTIVES

Information regarding serotype distributions of Streptococcus pneumoniae causing ophthalmic infections is scanty. This study was therefore undertaken to determine the antimicrobial susceptibility status and serotypes of S. pneumoniae isolated from various ophthalmic infections and to compare with those isolated from systemic infections and commensal nasopharyngeal flora.

METHODS

Thirty eight of S. pneumoniae isolates from ophthalmic infections, 9 from systemic infections and 14 from the nasopharynx of apparently healthy school children were biochemically characterized and tested for in vitro antimicrobial susceptibility to various antibiotics. Serotyping of these 61 isolates was done by a rapid co-agglutination method.

RESULTS

All the 61 isolates were sensitive to oxacillin (penicillin) and susceptibility against other antimicrobials was variable. No multidrug resistance was observed. The 38 ophthalmic isolates were distributed in 15 different serotypes. Most prevalent serotypes were 14, followed by 8 and 19F. The 9 systemic and 14 commensal. isolates of S. pneumoniae were distributed in 7 and 11 serotypes respectively. Three of the systemic and six of the commensal serotypes were observed in ophthalmic infections whereas four of the commensal serotypes were observed in systemic infections.

INTERPRETATION AND CONCLUSION

Resistance to penicillin was not observed. In ophthalmic infections, a wide range of serotypes of S. pneumoniae were observed. More than half of the commensal serotypes obtained in the study as well as majority of the systemic serotypes were observed in ophthalmic infections.

Intelligent compensation of friction, ripple, and hysteresis via a regulated chatter

In this paper, a hybrid control scheme utilizing a PID feedback control with an additional regulated chatter signal is developed to compensate motion impeding influences such as the effects due to friction, force ripples, and hysteresis in linear piezoelectric motor. The regulated chatter signal is a pulse sequence superimposed on the PID control signal. It has a fixed amplitude, and a pulse width regulated via iterative learning control. As such, the scheme is expected to be useful for applications involving iterative motion sequences. An analysis of the closed-loop performance is presented in the paper. Simulation and experimental results are also furnished to demonstrate that the proposed control scheme can reduce tracking errors significantly.

Viral hepatitis in India

Viral hepatitis is a major public health problem in India, which is hyperendemic for HAV and HEV. Seroprevalence studies reveal that 90%-100% of the population acquires anti-HAV antibody and becomes immune by adolescence. Many epidemics of HEV have been reported from India. HAV related liver disease is uncommon in India and occurs mainly in children. HEV is also the major cause of sporadic adult acute viral hepatitis and ALF. Pregnant women and patients with CLD constitute the high risk groups to contract HEV infection, and HEV-induced mortality among them is substantial, which underlines the need for preventive measures for such groups. Children with HAV and HEV coinfection are prone to develop ALF. India has intermediate HBV endemicity, with a carrier frequency of 2%-4%. HBV is the major cause of CLD and HCC. Chronic HBV infection in India is acquired in childhood, presumably before 5 years of age, through horizontal transmission. Vertical transmission of HBV in India is considered to be infrequent. Inclusion of HBV vaccination in the expanded programme of immunization is essential to reduce the HBV carrier frequency and disease burden. HBV genotypes A and D are prevalent in India, which are similar to the HBV genotypes in the West. HCV infection in India has a population prevalence of around 1%, and occurs predominantly through transfusion and the use of unsterile glass syringes. HCV genotypes 3 and 2 are prevalent in 60%-80% of the population and they respond well to a combination of interferon and ribavirin. About 10%-15% of CLD and HCC are associated with HCV infection in India. HCV infection is also a major cause of post-transfusion hepatitis. HDV infection is infrequent in India and is present about 5%-10% of patients with HBV-related liver disease. HCC appears to be less common in India than would be expected from the prevalence rates of HBV and HCV. The high disease burden of viral hepatitis and related CLD in India, calls for the setting up of a hepatitis registry and formulation of government-supported prevention and control strategies.

Non-alcoholic fatty liver disease may not be a severe disease at presentation among Asian Indians

AIM: To evaluate the clinical and biochemical profile of patients with non alcoholic fatty liver disease (NAFLD) and to assess their histological severity at presentation.

METHODS: Consecutive patients presenting to the liver clinic of All India Institute of Medical Sciences (AIIMS) with raised transaminases to at least 1.5 times upper limit of normal, and histologically confirmed non-alcoholic fatty liver disease were included. Patients who had significant alcohol intake or positive markers of other liver diseases or who were taking drugs known to produce fatty liver were excluded. The clinical, biochemical and histological profile of this group was studied.

RESULTS: Fifty-one patients with NAFLD formed the study population. Their median age and BMI were 34(17-58) years and 26.7(21.3-32.5) kg/m² respectively and 46 (90.1%) were males. The majority of the patients had mild inflammation, either grade 1 [32 (63%)] or grade 2 [16 (31%)] and only 3 (6%) patients had severe (grade 3) inflammation. Twenty-three (45%), 19 (37%), 8(16%) and 1(2%) patient had stage 0, 1, 2 and 3 fibrosis respectively on index biopsy and none had cirrhosis. On univariate analysis, triglyceride levels more than 150 mg % (OR = 7.1; 95% CI: 1.6-31.5, P = 0.002) and AST/ALT ratio > 1 (OR = 14.3; 95% CI: 1.4-678.5, P = 0.008) were associated with high grades of inflammation and none was associated with advanced fibrosis. On multivariate logistic regression analysis, hypertriglyceridemia >150 mg% was the only factor independently associated with presence of high grade of inflammation (OR = 1.6; 95% CI: 1.3-22.7, P = 0.02), while none was associated with advanced fibrosis. Triglyceride levels correlated positively with inflammatory grade (r = 0.412; P = 0.003).

CONCLUSION: NAFLD in North Indian patients is a disease of young over-weight males, most of whom are insulin resistant and they tend to have a mild histological disease at presentation.

Vitamin E-based therapy is effective in ameliorating transaminasemia in nonalcoholic fatty liver disease

BACKGROUND

Comparative trials of ursodeoxycholic acid (UDCA), vitamin E and weight management programs among patients with nonalcoholic fatty liver disease (NAFLD) are lacking.

AIM

To find an effective single agent or combination of agents for management of NAFLD.

METHODS

In this retrospective study, consecutive patient with histologically confirmed NAFLD with raised ALT were included. The patients received either weight management (exercise and therapeutic lifestyle changes [TLC] diet with a target to reduce body weight 10% in 6 months) (group I) ; weight management + UDCA (300 mg BID) (group II); or weight management + UDCA + vitamin E (400 mg OD) (group III). Outcome measure was normalization of ALT.

RESULTS

42 patients (18, 12 and 12 in groups I, II and III, respectively) were included between 1996 and 2004. All patients in group III normalized their ALT levels, which was significantly higher than numbers in group I (8/18) and group II (5/12); (p=0.003). Post treatment ALT was significantly lower in group III (28.6 [9.3]) as compared to group I (59.3 [32.2]) and group II (49.0[31.8]); (p=0.01). Type of therapy received was the only factor predictive of ALT normalization.

CONCLUSION

Combination regimen containing vitamin E appears to be effective in normalizing ALT among NAFLD patients.

Morphology and size dependent optical properties of CdS nanostructures

CdS nanoparticles with different sizes ranging from 2.5 nm to 300 nm and nanorods with aspect ratio -32 were synthesized by simple solvothermal process with a view to explore the effect of size and shape on the optical properties of these nanoforms. Solvent, temperature and the Cd source played important role in determining the morphologies and sizes of the nanocrystals. Comparative study of the optical properties of these nanoforms showed systematic changes in the optical absorption spectra with the reduction in particle size. Nanorods showed bulk like properties. Photoluminescence and Raman studies were carried out to explore the size and morphology dependent optical properties of the CdS nanoforms.

Utility of random amplification of polymorphic DNA assay and BOX-A PCR in molecular characterization of Streptococcus pneumoniae isolates recovered from various ophthalmic infections

BACKGROUND AND OBJECTIVES

Studies emphasizing the genotype distribution among ophthalmic isolates of Streptococcus pneumoniae are scarce. There is no conclusive information on genetic relatedness of the ophthalmic isolates with the commensal and systemic isolates of S. pneumoniae.

METHODS

To find out the relatedness between the ophthalmic, invasive and commensal isolates of S. pneumoniae, genotyping was carried out by using RAPD and BOX-A PCR assays. The serotyping was carried out by a rapid co-agglutination method using 12-pooled S. pneumoniae antisera.

RESULTS

Topological relationship was identified in order of similarity, and phylogenetic tree was drawn employing sequential clustering alogarithm by UPGMA linkage analysis. The 61 isolates were distributed in 17 RAPD types, 11 BOX-A types and 21 serotypes.

CONCLUSIONS

Both genotyping techniques were useful in terms of intraspecies genomic variation in S. pneumoniae. BOX-A PCR typing was found to be slightly superior to RAPD analysis in terms of reproducibility and standardization. No specific S. pneumoniae serotype or genotype was found to have special predilection to cause ophthalmic infections.

Photoluminescence and raman study of CdS-Al2O3 nanocomposite films prepared by sol-gel techniques

The optical and microstructural properties of CdS-Al2O3 nanocomposite (CdS-Al2O3 = 20:80 to 50:50) thin films synthesized by sol-gel techniques were studied. Optical transmission spectra indicated a marked blue shift of the absorption edge due to quantum confinement. Band gaps of CdS-Al2O3 nanocomposites were found to vary in the range 3.69-2.61 eV. The sizes of the nanocrystals, estimated from the blue shift (0.2-1.2 eV) of the absorption edges and transmission electron microscopy, were found to vary in the range 2.8-7.0 nm. X-ray diffraction studies showed reflections from (111), (200), (220), and (311) planes of CdS in the cubic phase. Microstructural characterization by high-resolution transmission electron microscope (HRTEM) indicated well crystallinity of the nanoparticles and lattice fringes supported the cubic phase of CdS. Raman spectroscopy was carried out for CdS-Al2O3 nanocomposites, which indicated a prominent peak at approximately 299 cm(-1). Significant changes in the peak position and intensity of the Raman peak were observed with varying the annealing temperature (373-573 K). Photoluminescence measurements indicated a prominent broad peak at approximately 1.81 eV due to the surface defects in the CdS nanocrystallites. The present study revealed Al2O3 to be a good capping material for CdS nanoparticles.

Periodic speed ripples minimization in PM synchronous motors using repetitive learning variable structure control

In this paper, we propose a simple repetitive learning variable structure control (RLVSC) scheme to reduce periodic speed ripples in a permanent magnet synchronous motor (PMSM). These speed ripples are induced by parasitic torque pulsations that vary periodically with rotor position. The conventional PI speed controller is able to reduce speed ripples to a certain extent but not sufficient enough for many high performance applications. During steady state, the RLVSC generates a reference compensation current that together with the outer loop PI speed controller is used to minimize the speed ripples. Being a plug-in module, the proposed RLVSC controller can be easily integrated to any of the existing PMSM drive systems. Experimental evaluation of the proposed scheme is carried out on a DSP-controlled PMSM drive platform. Test results obtained demonstrate the effectiveness of the proposed control scheme in reducing speed ripples by a factor of approximately 3 under various operating conditions.

Mother-to-child transmission of hepatitis E virus infection

OBJECTIVES

Water borne or enterically transmitted non-A-non-B hepatitis is a major public health problem in India. Many of these cases carry fatal outcome. The hepatitis E virus (HEV) has been considered to be the most important causative agent of this entity. The severity and fatality rates of HEV infection are reported to be rather more in pregnant women. However, there is meager information from India, on mother to child transmission of this agent.

METHODS

During 1997-98, we studied 60 pregnant women suspected to have acute viral hepatitis to understand the frequency of various viral etiologies, disease course and outcome of the pregnancy. Six cord blood samples were tested for IgG, and IgM antibodies against hepatropic viral agents and also for hepatitis E virus RNA by RT-nested PCR using ORF-1 as target.

RESULTS

Of the 60 pregnant patients hospitalised at All India Institute of Medical Sciences, New Delhi for acute hepatitis, 22 (37%) were positive for IgM anti-HEV antibodies and 10% were infected with hepatitis B virus. Co-infection of HEV with Hepatitis B and C was seen in 1 and 2 patents, respectively. Most (72%) of the HEV infected patients were in third trimester of pregnancy (P<0.05). Of the 6 cord blood samples tested 3 (50%) were positive for HEV RNA. Though, all mothers were RNA positive, half of the babies did not get infected in utero with HEV. Fourteen of the 22 (63.6%) HEV infected mothers developed fulminant hepatic failure and all died.

CONCLUSION

The mortality rate in HEV [corrected] infected mothers was 100%. Mother to child transmission of hepatitis E virus infection was established in 50%.

Etiopathogenesis of acute hepatic failure: Eastern versus Western countries

Etiopathogenesis of acute hepatic failure (AHF) in Eastern and Western countries is distinct. In the East hepatitis viruses cause AHF in more than 95% of such cases, while causes of AHF in the West are quite heterogenous. Hepatitis E virus is the major etiological agent of AHF in countries like India where the virus is hyperendemic. Occult HBV infection may also be causing AHF in a sizable proportion of cases in areas where chronic HBV infection frequency is high. Paracetamol causes AHF in about 70% cases in the UK and about 20% cases in USA, whereas in France and Denmark, non-steroidal anti-inflammatory drugs are more frequently associated with AHF. Hepatitis B virus causes AHF in about one-third of cases in the latter two countries.

Vaccination for hepatitis A virus is not required for patients with chronic liver disease in India

BACKGROUND

Hepatitis A virus (HAV) vaccination is recommended worldwide for patients with chronic liver disease to prevent decompensation due to superinfection with HAV. India being endemic for HAV, the prevalence of pre-existing antibodies against HAV due to subclinical exposure to the virus in childhood among patients with chronic liver disease may be high and, therefore, vaccination may not be needed. However, data are lacking on the prevalence of HAV antibody among patients with chronic liver disease in India.

METHODS

Two hundred fifty-four patients attending the Liver Clinic at the All India Institute of Medical Sciences, New Delhi during the past 5 years and diagnosed to have either chronic hepatitis due to the hepatitis B virus (n = 76), hepatitis C virus (n = 84) or cirrhosis of the liver due to the hepatitis B (n = 47) or C (n = 47) virus were tested for the presence of IgG anti-HAV antibody in their sera (using a commercial ELISA kit).

RESULTS

Two hundred forty-eight (97.6%) patients tested positive for IgG anti-HAV. The prevalence of anti-HAV positivity was similar among patients with chronic hepatitis B (74, 97.4%), chronic hepatitis C (82, 97.6%), cirrhosis of the liver due to the hepatitis B (46, 97.8%) and hepatitis C (46, 97.8%) virus.

CONCLUSION

Vaccination against HAV is not required among patients with chronic liver disease in India as there is a very high prevalence of pre-existing antibodies in these patients.

Sero-epidemiology of hepatitis E virus (HEV) in urban and rural children of North India

OBJECTIVE

To estimate the prevalence of anti-HEV IgG and IgM antibodies to ORF3 peptide of Hepatitis E virus genome in an age stratified urban and rural population of children.

DESIGN

Cross sectional survey.

SETTING

Pediatric out-patient clinics in a tertiary hospital and a rural dispensary.

METHODS

Study subjects between 6 months and 10 years with minor, non-hepatic illnesses were recruited for the study from March to December 1996. Baseline demographic details, drinking water source, sewage disposal methods, reasons for attending the hospital, histories of parenteral exposure in the past 12 months and acute hepatitis in the subjects and the family in the previous six months were obtained. Serum anti-HEV IgG antibodies were screened in all subjects, and in those who were positive, anti-HEV IgM antibodies were assayed as an indicator of recent infection. Serum aminotransferase (ALT) was estimated in those who were anti-HEV IgM antibody positive.

RESULT

Out of 2160 subjects recruited, 2070 samples could be screened for anti-HEV IgG antibodies. In the urban population (n = 1065) anti-HEV IgG antibodies were detected in 306 subjects (28.7%; 95% CI 26.0-31.6) and of these 131 (42.8%; 95%CI 37.2-48.6) were anti-HEV IgM antibody positive. Amongst 1005 rural children, anti-HEV IgG antibodies were present in 239 (23.8%; 95% CI 21.1-26.4) and IgM antibodies in 113 (47.3%; 95% CI 40.9-53.7) children. The antibodies were present since the first year of age till 10 years of age and, increased with advancing age. Serum transaminases were raised in 7.5% (9/120) and 5.5% (5/88) of subjects with anti-HEV IgM antibodies in urban and rural centers respectively. Overall the seroprevalence of IgG antibodies against HEV were significantly more in urban as compared to that in rural subjects (p = 0.011). However, proportion of children with anti-HEV IgG carrying IgM antibodies was similar in the two study groups (p = 0.298). A model for estimating expected prevalence of anti-HEV IgG antibodies was developed. The observed antibody prevalence in both urban and rural subjects at each age interval after 48 months was less as compared to the expected levels and this gap increased with advancing age categories. It appeared that there was a decay of HEV antibodies with time.

CONCLUSIONS

Children are susceptible to HEV infection since early infancy. The probability of exposure to HEV during childhood was higher in urban than rural population. Seropositivity to HEV antibodies increased by over 2 times beyond 4 years of age as compared to younger age. Anti-HEV IgG antibodies appear to wean off with increasing age.

Urinary excretion pattern of catecholestrogens in preovulatory LH surge during the 4-day estrous cycle of rats

The formation of catecholestrogens represents a major pathway of estrogen metabolism and catecholestrogens are regarded as the main estrogen metabolite in non-pregnant state of various mammalian systems. In the present investigation, level of 2-hydroxyestrone, the major catecholestrogen excreted in rat urine, was measured by radioimmunoassay following acid hydrolysis and column chromatography of the 24-h urine samples of female Sprague Dawley non-pregnant rats during their 4-day estrous cycle. Urinary levels of estrone, estradiol and estriol were measured. Unlike the plasma level, urinary 2-hydroxyestrone showed a marked increase during the pre-ovulatory LH surge suggesting a plausible role of catecholestrogen in the mid-cycle elevation of the gonadotropin level in normal cycling rats.

The 3' end of hepatitis E virus (HEV) genome binds specifically to the viral RNA-dependent RNA polymerase (RdRp)

Hepatitis E virus (HEV) is the major cause of acute epidemic and sporadic hepatitis in the developing world. It is a positive-strand RNA virus with a genome length of about 7.2 kb. The replication mechanism of this virus is virtually unexplored. Identification of the regulatory elements involved in initiation of replication may help in designing specific inhibitors for therapy. In the positive-stranded RNA viruses the initiation of replication requires interaction of the 3' end of genome with its RNA-dependent RNA polymerase (RdRp) and possibly host-derived cofactors for synthesis of the minus-strand replicative intermediate. Secondary structure prediction of the conserved 3' end of the infectious HEV genome was carried out to identify possible stem-loop structures necessary for RNA-protein interaction and the model was confirmed by structure probing experiments. Electrophoretic mobility-shift assays showed specific binding of purified and refolded recombinant HEV RdRp protein to the 3' end of its RNA genome containing the poly(A) stretch. Mutations at the 3' end, in which the stem-loop structures were partially or completely destroyed or recreated revealed that the two stem-loop structures SL1 and SL2 at the 3' end and the poly(A) stretch are necessary for this binding. The interacting nucleotides in such an interaction were further identified by generating footprints of the complex by Pb(II)-induced hydrolysis. This specific binding of viral RdRp to the 3' end of HEV RNA directs the synthesis of complementary-strand RNA and thus such a binding domain might assume the role of a possible cis-acting element as a potential site for the initiation of replication.

Acute hepatic failure in India: a perspective from the East

Acute hepatic failure (AHF) in India almost always presents with encephalopathy within 4 weeks of the onset of acute hepatitis. Further subclassification of AHF into hyperacute, acute and subacute forms may not be necessary in this geographical area, where the rapidity of onset of encephalopathy does not seem to influence survival. Viral hepatitis is the cause in approximately 95-100% of patients, who therefore constitute a more homogeneous population than AHF patients in the West. In India, hepatitis E (HEV) and hepatitis B (HBV) viruses are the most important causes of AHF; approximately 60% of cases are caused by to these viruses. Hepatitis B virus core mutants are very important agents in cases where hepatitis B results in AHF in this country. Half of the patients with AHF admitted to our centre are female, one-quarter of whom are pregnant. Therefore, pregnant females who contract viral hepatitis constitute a high-risk group for the development of AHF. However, the outcome of AHF in this group is similar to that in non-pregnant women and men. No association with any particular virus has been identified among sporadic cases of AHF. In our centre, approximately one-third of AHF patients survive with aggressive conservative therapy, whereas two-thirds of deaths occur within 72 h of hospitalization. Cerebral oedema and sepsis are the major fatal complications. Both fungal and gram-negative bacteria are major causes of sepsis. Among patients with AHF, despite the presence of sepsis, its overt clinical features (i.e. fever, leucocytosis) may be absent and objective documentation of the presence of sepsis in such patients is achieved by repeated culture of various body fluids. It should be possible to develop simple, clinical prognostic markers for AHF in this geographical region, in order to identify patients suitable for liver transplantation.

Cloning, sequencing, and expression of the hepatitis E virus (HEV) nonstructural open reading frame 1 (ORF1)

Hepatitis E virus (HEV) causes enterically transmitted epidemic and sporadic viral hepatitis affecting millions of people in the developing world. Different geographical isolates of HEV show a high degree of homology at the nucleotide and amino acid levels. The approximately 7.2 kb RNA genome has three open reading frames of which ORF1 is predicted to code for the viral nonstructural polyprotein. The expression, processing and properties of the nonstructural ORF1 polyprotein have not been reported so far. In this study, the complete HEV ORF1 was reconstructed from overlapping fragments amplified by polymerase chain reaction (PCR) of total RNA isolated from the bile fluid of a rhesus monkey experimentally infected with HEV isolate from an epidemic. The complete assembled ORF1 was sequenced using HEV specific primers. The ORF1 polyprotein was expressed in E. coli, in a cell free translation system and in HepG2 cells, and was characterized by western blotting and immunoprecipitation using acute phase patient serum as well as polyclonal antibodies raised against defined parts of the ORF1 polyprotein. The nonstructural polyprotein of HEV was expressed as a 186 kDa protein. No processing was observed into discrete units, either in-vitro based on a kinetic analysis, or in HepG2 cells based on immunoprecipitation.

The in vitro-synthesized RNA from a cDNA clone of hepatitis E virus is infectious

Hepatitis E virus (HEV) is an important etiological agent of epidemic and sporadic hepatitis, which is endemic to the Indian subcontinent and prevalent in most of the developing parts of the world. The infection is often associated with acute liver failure and high mortality, particularly in pregnant women. In order to develop methods of intervention, it is essential to understand the biology of the virus. This is particularly important as no reliable in vitro culture system is available. We have constructed a cDNA clone encompassing the complete HEV genome from independently characterized subgenomic fragments of an Indian epidemic isolate. Transfection studies were carried out with HepG2 cells using in vitro-transcribed RNA from this full-length HEV cDNA clone. The presence of negative-sense RNA, indicative of viral replication, was demonstrated in the transfected cells by strand-specific reverse transcription-PCR and slot blot hybridization. The viral proteins pORF2 and pORF3 and processed components of the pORF1 polyprotein (putative methyltransferase, helicase, and RNA-dependent RNA polymerase) were identified in the transfected cells by metabolic pulse-labeling with [(35)S]methionine-cysteine, followed by immunoprecipitation with respective antibodies. The expression of viral proteins in the transfected cells was also demonstrated by immunofluorescence microscopy. Viral replication was detected in the transfected cells up to 33 days posttransfection (six passages). The culture supernatant from the transfected cells was able to produce HEV infection in a rhesus monkey (Macaca mulatta) following intravenous injection, indicating the generation of viable HEV particles following transfection of cells with in vitro-synthesized genomic RNA. This transient cell culture model using in vitro-transcribed RNA should facilitate our understanding of HEV biology.