Fecal microbiota transplantation compared with prednisolone in severe alcoholic hepatitis patients: a randomized trial

BACKGROUND

Severe alcoholic hepatitis (SAH) has high 90-day mortality. Prednisolone therapy has shown modest survival benefits over placebo at 28 but not 90 days. Fecal microbial transplantation (FMT) has shown promise in these patients. We compared the efficacy and safety of the two therapies in SAH patients.

METHODS

Steroid eligible SAH patients were randomized in an open-label study to prednisolone (n = 60) 40 mg/day for 28 days (assessed at day-7 for continuation) or healthy donor FMT (n = 60) through naso-duodenal tube, daily for seven days. Primary outcome of study was day-90 survival.

RESULTS

Patients in prednisolone and FMT arms were comparable at baseline (discriminant function score 65 ± 16.2 and 68 ± 14, MELD score 17.1 and 16.5, respectively). Of 120 patients, 112 [prednisolone-57; FMT-55] completed trial. As per intention-to-treat analysis, 90-day survival was achieved by 56.6% (34/60) patients in prednisolone and 75% (45/60) in FMT group (p = 0.044, FMT HR = 0.528, 95%CI 0.279-0.998). Secondary outcome of 28-day survival [78.33% (47/60) and 88.33% (53/60) (p = 0.243, FMT HR = 0.535, 95%CI 0.213-1.34)] with comparable severity scores over time between both arms. Infections accounted for 11 (19.3%) and 2 (3.6%) deaths in prednisolone and FMT groups, respectively (p = 0.01). Path-tracing showed a slow establishment of microbiota and alpha diversity (Shannon index) improvement by day-28 (p = 0.029). FMT resulted in 23 new taxa by day-28, reduction from baseline in pathogenic taxa [Campylobacter (19-fold, p = 0.035), anaerobes (Parcubacteria, Weisella and Leuconostocaceae)], and increase of Alphaproteobacteria [~ sevenfold, p = 0.047] and Thaumarcheota (known ammonia oxidizer, p = 0.06). Lachnospiraceae (p = 0.008), Prevotella and Viellonella communities in gut favored survival (p < 0.05).

CONCLUSION

In severe alcoholic hepatitis, FMT is safe and improves 90-day survival and reduces infections by favorably modulating microbial communities. It can be a useful alternative to prednisolone therapy.

A New Variant of an Old Itch: Novel Missense Variant in ABCB4 Presenting with Intractable Pruritus

We report a novel homozygous missense variant in ABCB4 gene in a Yemeni child born to consanguineous parents, with a significant family history of liver disease-related deaths, resulting in a progressive familial intrahepatic cholestasis (PFIC) type 3 phenotype requiring liver transplantation for intractable pruritus.

Attenuation of 7-ketocholesterol- and 7β-hydroxycholesterol-induced oxiapoptophagy by nutrients, synthetic molecules and oils: Potential for the prevention of age-related diseases

Age-related diseases for which there are no effective treatments include cardiovascular diseases; neurodegenerative diseases such as Alzheimer's disease; eye disorders such as cataract and age-related macular degeneration; and, more recently, Severe Acute Respiratory Syndrome (SARS-CoV-2). These diseases are associated with plasma and/or tissue increases in cholesterol derivatives mainly formed by auto-oxidation: 7-ketocholesterol, also known as 7-oxo-cholesterol, and 7β-hydroxycholesterol. The formation of these oxysterols can be considered as a consequence of mitochondrial and peroxisomal dysfunction, leading to increased in oxidative stress, which is accentuated with age. 7-ketocholesterol and 7β-hydroxycholesterol cause a specific form of cytotoxic activity defined as oxiapoptophagy, including oxidative stress and induction of death by apoptosis associated with autophagic criteria. Oxiaptophagy is associated with organelle dysfunction and in particular with mitochondrial and peroxisomal alterations involved in the induction of cell death and in the rupture of redox balance. As the criteria characterizing 7-ketocholesterol- and 7β-hydroxycholesterol-induced cytotoxicity are often simultaneously observed in major age-related diseases (cardiovascular diseases, age-related macular degeneration, Alzheimer's disease) the involvement of these oxysterols in the pathophysiology of the latter seems increasingly likely. It is therefore important to better understand the signalling pathways associated with the toxicity of 7-ketocholesterol and 7β-hydroxycholesterol in order to identify pharmacological targets, nutrients and synthetic molecules attenuating or inhibiting the cytotoxic activities of these oxysterols. Numerous natural cytoprotective compounds have been identified: vitamins, fatty acids, polyphenols, terpenes, vegetal pigments, antioxidants, mixtures of compounds (oils, plant extracts) and bacterial enzymes. However, few synthetic molecules are able to prevent 7-ketocholesterol- and/or 7β-hydroxycholesterol-induced cytotoxicity: dimethyl fumarate, monomethyl fumarate, the tyrosine kinase inhibitor AG126, memantine, simvastatine, Trolox, dimethylsufoxide, mangafodipir and mitochondrial permeability transition pore (MPTP) inhibitors. The effectiveness of these compounds, several of which are already in use in humans, makes it possible to consider using them for the treatment of certain age-related diseases associated with increased plasma and/or tissue levels of 7-ketocholesterol and/or 7β-hydroxycholesterol.

Endoscopic third ventriculostomy versus ventriculoperitoneal shunt in pediatric and adult population: a systematic review and meta-analysis

Treatment options for hydrocephalus include endoscopic third ventriculostomy (ETV) and ventriculoperitoneal shunt (VPS). Some ambiguity remains regarding indications, safety, and efficacy for these procedures in different clinical scenarios. The objective of the present study was to pool the available evidence to compare outcomes among patients with hydrocephalus undergoing ETV versus VPS. A systematic search of the literature was conducted via PubMed, EMBASE, and Cochrane Library through 11/29/2018 to identify studies evaluating failure and complication rates, following ETV or VPS. Pooled effect estimates were calculated using random effects. Heterogeneity was assessed by the Cochrane Q test and the I² value. Heterogeneity sources were explored through subgroup analyses and meta-regression. Twenty-three studies (five randomized control trials (RCTs) and 18 observational studies) were meta-analyzed. Comparing ETV to VPS, failure rate was not statistically significantly different with a pooled relative risk (RR) of 1.48, 95%CI (0.85, 2.59) for RCTs and 1.17 (0.89, 1.53) for cohort studies; P-interaction: 0.44. Complication rates were not statistically significantly different between ETV and VPS in RCTs (RR: 1.34, 95%CI: 0.50, 3.59) but were statistically significant for prospective cohort studies (RR: 0.47, 95%CI: 0.30, 0.78); P-interaction: 0.07. Length of hospital stay was no different, when comparing ETV and VPS. These results remained unchanged when stratifying by intervention type and when regressing on age when possible. No significant differences in failure rate were observed between ETV and VPS. ETV was found to have lower complication rates than VPS in prospective cohort studies but not in RCTs. Further research is needed to identify the specific patient populations who may be better suited for one intervention versus another.

Efficacy of Granulocyte Colony-stimulating Factor in the Management of Steroid-Nonresponsive Severe Alcoholic Hepatitis: A Double-Blind Randomized Controlled Trial

Severe alcoholic hepatitis (SAH) is often a progressive disease with high mortality and limited steroid responsiveness. Management options of steroid nonresponsive SAH (day 7 Lille score > 0.45) are limited. We assessed the efficacy and safety of granulocyte colony-stimulating factor (G-CSF) in steroid nonresponders. A randomized, double-blind, single-center trial (NCT01820208) was conducted between March 2013 and June 2016 in patients with histologically proven SAH, nonresponsive to 40 mg/day of prednisolone were randomized to G-CSF (12 doses, 300 μg each in 28 days) or placebo. Responders were continued with prednisolone. Of the 430 patients with SAH, 132 received steroid therapy. Of these, 33 (25%) were nonresponders and were randomized to G-CSF or placebo (14 in each group after exclusions). The baseline characteristics of both groups were comparable. The 28-day mortality was comparable between the groups (21.4%, G-CSF; 28.6%, placebo; P = 0.69). At 90 days, in the G-CSF but not in the placebo group, the Model for End-Stage Liver Disease reduced from 24.6 ± 3.9 to 19.4 ± 3.7 (P = 0.002) and Maddrey's discriminant function from 74.8 ± 22.8 to 57.4 ± 31 (P = 0.26). Infections were less common (28% versus 71%; P < 0.001) with lower 90-day mortality (35.7% versus 71.4%; P = 0.04) in the G-CSF than in the placebo group. On Cox regression analysis, receiving G-CSF (hazard ratio, 0.37; SD, 0.14-0.98; P = 0.04), and high baseline serum creatinine (hazard ratio, 4.12; SD, 1.7-10.3; P = 0.002) predicted day-90 outcomes in steroid nonresponsive SAH. Patients tolerated G-CSF without any major adverse events. Conclusion: Approximately one-quarter of patients with SAH do not respond to corticosteroid therapy. Administration of G-CSF is safe and helps to reduce the disease severity and 90-day mortality in these patients.

Microbiome as a therapeutic target in alcohol-related liver disease

Alcohol-related liver disease is associated with significant changes in gut microbial composition. The transmissibility of ethanol-induced liver disease has been demonstrated using faecal microbiota transfer in preclinical models. This technique has also led to improved survival in patients with severe alcoholic hepatitis, suggesting that changes in the composition and function of the gut microbiota are causatively linked to alcohol-related liver disease. A major mechanism by which gut microbiota influence the development of alcohol-related liver disease is through a leaky intestinal barrier. This permits translocation of viable bacteria and microbial products to the liver, where they induce and promote inflammation, as well as contribute to hepatocyte death and the fibrotic response. In addition, gut dysbiosis is associated with changes in the metabolic function of the intestinal microbiota, bile acid composition and circulation, immune dysregulation during onset and progression of alcohol-related liver disease. Findings from preclinical and human studies will be used to demonstrate how alcohol causes intestinal pathology and contributes to alcohol-related liver disease and how the latter is self-perpetuating. Additionally, we summarise the effects of untargeted treatment approaches on the gut microbiota, such as diet, probiotics, antibiotics and faecal microbial transplantation in alcohol-related liver disease. We further discuss how targeted approaches can restore intestinal homeostasis and improve alcohol-related liver disease. These approaches are likely to add to the therapeutic options for alcohol-related liver disease independently or in conjunction with steroids.

Influenza a infection unmasking an underlying mitral valve stenosis in a 19-year-old boy

Infection with Influenza virus is uncommon in the present times, though a number of cases were reported during pandemics in 1918 in various regions of America. We report a case where a young male patient presented to the hospital with a clinical picture of acute respiratory distress syndrome that turned out to be a viral pneumonia caused by Influenza A virus and it aggravated an underlying yet undiagnosed mitral valve stenosis.

Pulmonary tuberculosis presenting acutely as paraplegia: an unusual presentation

Extrapulmonary tuberculosis most commonly involves the bones and the spine. The present case is that of a young boy who presented with acute onset paraplegia without any pre-existant complaints of cough with sputum, fever, night sweats or weight loss.

A case report of Plasmodium vivax, Plasmodium falciparum and dengue co-infection in a 6 months pregnancy

India being a tropical country, parasitic infections especially with Plasmodium species are very common in this region. The present case report is that of Plasmodium vivax, Plasmodium falciparum and dengue co-infection in a 6 months pregnant lady who was timely diagnosed and appropriately treated followed by a complete recovery along with feto-maternal well-being.

A case of Staphylococcus toxic shock syndrome presenting with multiple pneumatocoeles in the chest

Staphylococcus toxic shock syndrome is a severe illness caused by infection with toxin producing Staphylococcus aureus and is associated with a poor outcome. We report a case of Staphylococcus TSS presenting with cough and expectoration along with multiple pneumatoceles visible on the chest radiograph that progressed to acute respiratory distress syndrome with eventual foci in brain. The patient was aggressively managed and recovered completely.

Clinical profile of severe malaria: study from a tertiary care center in north India

One hundred and sixty patients having clinical features of severe malaria reported during monsoon season-August-October 2010 at this tertiary care center of north India. Of these 110 (68.75 %) had Plasmodium vivax infection, 30 (18.75 %) were infected with P. falciparum and 20 (12.5 %) had co-infection due to P. vivax and P. falciparum. The diagnosis was made using Rapid Card Test and was confirmed by peripheral smear examination of thick and thin films. Several complications such as acute kidney injury, jaundice, severe anemia, metabolic acidosis, shock, hyperpyrexia, hypoglycemia, generalized tonic-clonic convulsions etc. were found to be more prevalent in patients with P. vivax infection. These symptoms were until recently known to be associated with falciparum malaria.

Screening of cardiovascular autonomic neuropathy in patients with diabetes using non-invasive quick and simple assessment of sudomotor function

AIM

Cardiovascular autonomic neuropathy (CAN) is a common but often overlooked complication of diabetes. Sympathetic C-fibers innervating sweat glands can be impaired early on in patients with diabetes. In this study, SUDOSCAN, a new non-invasive device that assesses sudomotor function was compared to methods generally used for the investigation of CAN.

PATIENTS

A total of 232 patients with diabetes were measured for heart rate variability (HRV) at rest and during moderate activity. Time and frequency domain analysis techniques, including measurement of the low-frequency (LF) domain component, were assessed during HRV testing. Ewing tests, as recommended by the French Health Authority, were also done. Electrochemical sweat conductance (ESC) was measured on the hands and feet, and a risk-score was calculated.

RESULTS

Using two abnormal Ewing tests as a reference for the area under the curve (AUC) of the receiver operating characteristics (ROC) curve for SUDOSCAN, the risk-score was 0.74, with a sensitivity of 92% and specificity of 49% for a risk-score cut-off value of 35%. For the ROC curve analysis using the LF power component during moderate activity at a threshold of 90 ms(2) (first quartile) as reference, the AUC was higher for the SUDOSCAN risk-score (0.77) compared with the standard Ewing tests [E:I ratio (0.62), 30:15 ratio (0.76) and blood pressure change on standing (0.55)]. Using a cut-off value of 35%, risk-score sensitivity and specificity were 88 and 54%, respectively.

CONCLUSION

SUDOSCAN, which allows quick quantitative assessment of sudomotor function, may be used for early screening of CAN in everyday clinical practice before resorting to the more sophisticated and specific, but ultimately more time-consuming, Ewing tests.

A Case of Pulmonary Tuberculosis Presenting as Multiple Nodular Opacities on a Chest X-Ray

Tuberculosis is widely prevalent in India. The presentation of pulmonary tuberculosis as multiple nodular opacities on a chest X-ray is very infrequent. We report such a case in a 30-year-old man, who presented with the complaints of dyspnea and responded to anti-tuberculosis treatment.

TKI258 (dovitinib lactate) in metastatic renal cell carcinoma (mRCC) patients refractory to approved targeted therapies: A phase I/II dose finding and biomarker study

3563

Background: TKI258 is a potent receptor tyrosine kinase inhibitor (TKI) that selectively targets VEGFR, PDGFR, FGFR, CSF1R, c-KIT, RET, TrKA, and FLT3. Compared to other TKI agents, TKI258 additionally targets FGFR. FGF has been reported as an important escape mechanism of anti-VEGFR therapies. Methods: The primary objective of this phase I was to determine the maximum tolerated dose (MTD) of TKI258, administered orally on a 5 days on / 2 days off schedule in repeated 28 day cycles, in mRCC pts refractory to standard therapies. A two-parameter Bayesian logistic regression model and safety data for at least 21 pts will be used to determine MTD. Results: A phase I study is ongoing. As of December 2008, 11 pts (9 m, 2 f), median age: 55 (29–66 yrs) have been enrolled. Four pts have been treated at 500 mg/day (start dose): 2 are ongoing at cycle (C) 7; 1 pt discontinued due to PD and 1 due to sinus bradycardia. Five pts received 600 mg/day: 2 DLTs (G4 hypertension and G3 fatigue - pts discontinued) leading to dose reduction of all patients to 500mg/day; 2 pts in C5 and C4, 1 pt discontinued for PD. Two pts just entered the extension cohort at 500 mg. Other toxicities ≥G2 included fatigue, nausea, vomiting, diarrhea, neutropenia, folliculitis and dizziness. PK data showed CMax range (180–487 ng/mL, n = 8), and AUC range (2200–8251 ng/mL*h). Preliminary biomarker data indicated pts had high baseline VEGF (506 ± 203 pg/ml, n=6) and bFGF (220 ± 185 pg/ml, n = 6) levels, which may reflect failure of previous anti-VEGF agents. Induction of plasma FGF23 levels, a pharmacodynamic biomarker of FGFR1 inhibition, was observed in pts from the first 500 mg/day dosing cohort. Preliminary evidence of efficacy is observed with one minor response (-17% at C4), 4 stable disease and 1 dramatic shrinkage/necrosis of some target lesions (lymph node & suprarenal mass). Conclusions: TKI258 500mg/day seems a feasible schedule in heavily pre-treated mRCC patients with some indications of clinical benefit. These preliminary findings will be confirmed in the extension cohort.

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Cell culture adapted sheeppox virus as a challenge virus for potency testing of sheeppox vaccine

Sheeppox virus from an outbreak of sheeppox that occurred in Srinagar (Jammu and Kashmir, India) in 2000 was isolated by inoculation of susceptible sheep and further re-isolated in cell culture. The field virus, adapted to grow in lamb testes culture, was evaluated for its potential use as challenge virus in potency testing of sheeppox vaccine currently in use. The virus (passage 6) produced severe disease in susceptible sheep when inoculated subcutaneously with a dose of 106.2 TCID50. The virus identity was confirmed by PCR, sequencing of P32 gene and species-specific signature residues identified in deduced aa sequence of the gene. The virus was successfully evaluated for its virulence using two batches of sheep pox vaccines. Use of this field virus enables consistent potency experiments of sheeppox vaccines avoiding use of animals for its propagation and titration.

Surgical resection for pancreatic cancer: Correlates of margin positivity

4097

Background: Positive surgical margins (PSMs) occur in 20–40% of pancreatic cancer cases treated surgically. PSMs are associated with local recurrence and poor survival. Objectives: Correlate clinicopathological parameters with PSMs in pancreatic cancer patients (pts) undergoing surgical resection. Methods: Clinicopathological data for 71 pts who underwent surgical resection for pancreatic cancer from 1999–2005 were obtained. Data including location, AJCC stage, tumor size, type of resection, use of neoadjuvant therapy, grade, morphology, perineural and angiolymphatic invasion were correlated with PSMs and survival using logistic regression, Fisher-exact test and log-rank test. Results: There were 29 males; median age was 65 years and median follow-up 14 months. Histologies were: adenocarcinoma (n = 67), sarcomatoid (n = 2), adenosquamous (n = 1) and mucinous cystadenocarcinoma (n = 1). Sites of disease were: head only (n = 56), head/uncinate (n = 7) and body/tail (n = 8). Surgical treatments included Whipple (n = 43), pylorus preserving Whipple (n = 18) distal pancreatectomy (n = 8) and total pancreatectomy (n = 2). Pathological AJCC stages were: ΙA (n = 4), ΙB (n = 2), ΙΙA (n = 14), ΙΙB (n = 48), and ΙΙΙ (n = 3). Neoadjuvant chemoradiation (CRT) was administered in 10 cases; 38 other pts received postoperative adjuvant therapy including CRT (n = 36)/chemotherapy only (n = 2). Overall median survival was 30 months and disease free survival 18.6 months. Nineteen cases (27%) had PSMs. PSMs were pancreatic transection line (n = 11), retroperitoneal margin (n = 9), bile duct (n = 1) and peripancreatic soft tissue (n = 2). On univariate analysis, PSM was associated with advanced AJCC stage (p = 0.02) and tumor location other than pancreatic head (p = 0.02). PSM rate was 10% (1/10) and 31% (18/61) for pts with/without neoadjuvant therapy, respectively (p = 0.27). On multivariate analysis, PSM correlated with AJCC stage (p = 0.04) and tumor location (p = 0.05). PSMs were not significantly related to survival or recurrence (p = 0.09). Conclusions: Advanced AJCC stage and tumor in pancreatic body/tail or uncinate are associated with PSMs following pancreatic cancer resection. Strategies to “downstage” with novel therapies prior to surgery should be investigated to facilitate a complete surgical resection.

[Table: see text]

Epithelial-mesenchymal transition (EMT) in resected pancreatic cancer

4094

Background: EMT plays an important role in tumor invasion and metastases; its detection may have prognostic significance. We examined expression of EMT related proteins in resected pancreatic cancers and correlated results with clinical outcome. Methods: Clinical data/surgical specimens from 34 consecutive pancreatic cancer patients (pts) who underwent pancreatectomy from 1996–2002 were included. Immunohistochemical staining for vimentin (Vim 3B4), E-cadherin (36B5), MIB1 and cytokeratin (CK-AE1/AE3) was performed on formalin fixed paraffin embedded tissues. Percentages of stained cells (cytoplasmic for vimentin and CK, nuclear for MIB1 and membranous for E-cadherin) were recorded. The results were correlated with clinicopathological parameters and survival. Survival analysis (log-rank test, Cox-proportional hazard model), categorical data analysis (Pearson’s chi-square, logistic regression) and Kendall’s tau were performed at the significance level of 0.05. Results: Clinical data/specimens from 34 pts were included: 13 males, median age 66 (range 38–84); SEER stage 1 (2 pts), 2 (27 pts), 3 (5 pts); histological grade 1 (4), 2 (13), 3 (16), 4 (1). Median survival was 15 months (95% CI: 11–24 months). Sixteen pts had adjuvant chemoradiotherapy, 4 pts had chemotherapy, 1 pt had radiation. IHC Results: vimentin (11.8%), MIB1 (100%), E-cadherin (91%) and CK (100%). There was a significant negative association between vimentin and E-cadherin expression (Kendall’s tau = −0.47, p = 0.0024). Vimentin expression correlated with histological grade (exact chi-square p = 0.0247). No associations were found between these proteins and SEER stage, age, treatment or smoking. Univariate analysis revealed histological grade 50% (p = 0.0039) and MIB1 expression >10% (p = 0.0224) were related to better survival. Multivariate analysis using Cox-proportional hazard model revealed the following significant variables: histological grade (hazard ratio (HR) = 11.8, p = 0.0001), age (HR = 1.1, p = 0.0053), MIB1 (HR = 0.9, p = 0.0003) and adjuvant chemotherapy (HR = 0.2, p = 0.0288). Conclusion: Decreased E-cadherin expression (<50% expression) was associated with poorer survival; E-cadherin expression had an inverse correlation with vimentin. Acknowledgement: Supported by OSI Pharmaceuticals.

[Table: see text]

The glycosylation pattern of baculovirus expressed envelope protein E2 affects its ability to prevent infection with bovine viral diarrhoea virus

We have investigated the role of glycosylation of the envelope glycoprotein E2 of bovine viral diarrhoea virus (BVDV), produced in insect cells, in BVDV infection. When amino acids predicated to code for the C-terminal N-linked glycosylation site were mutated the resulting protein was less efficient than wild type protein at preventing infection of susceptible cells with BVDV. In addition, mutational analysis showed that a further two predicted N-terminal N-linked glycosylation sites of E2 are required for efficient production of recombinant protein.

Acetylator status, drug metabolism and disease

Acetylation polymorphism, although discovered 40 years ago, still holds interest not only because many drugs and carcinogens are metabolized by acetylation in the liver but also because advances have been made in the understanding of the molecular genetics of acetylation. It is this genetic variation of drug metabolism that is one of the causes of inter-individual variation of the effect of a drug. Acetylation polymorphism relates to the metabolism of a number of arylamine and hydrazine drugs and carcinogens by cytosolic N-acetyltransferase--NAT2. In humans, 2 genes--NAT1 and NAT2--are responsible for the N-acetyltransferase activity. Studies have revealed several allelic variants of both NAT1 and NAT2. It has been suggested that some of these variants modify the individual susceptibility to disease.

Enhanced crystallization of the Cys18 to Ser mutant of bovine gammaB crystallin

The cysteine residues of the gamma crystallins, a family of ocular lens proteins, are involved in the aggregation and phase separation of these proteins. Both these phenomena are implicated in cataract formation. We have used bovine gammaB crystallin as a model system to study the role of the individual cysteine residues in the aggregation and phase separation of the gamma crystallins. Here, we compare the thermodynamic and kinetic behavior of the recombinant wild-type protein (WT) and the Cys18 to Ser (C18S) mutant. We find that the solubilities of the two proteins are similar. The kinetics of crystallization, however, are different. The WT crystallizes slowly enough for the metastable liquid-liquid coexistence to be easily observed. C18S, on the other hand, crystallizes rapidly; the metastable coexisting liquid phases of the pure mutant do not form. Nevertheless, the coexistence curve of C18S can be determined provided that crystallization is kinetically suppressed. In this way we found that the coexistence curve coincides with that of the WT. Despite the difference in the kinetics of crystallization, the two proteins were found to have the same crystal forms and almost identical X-ray structures. Our results demonstrate that even conservative point mutations can bring about dramatic changes in the kinetics of crystallization. The implications of our findings for cataract formation and protein crystallization are discussed.

Crystal cataracts: human genetic cataract caused by protein crystallization

Several human genetic cataracts have been linked recently to point mutations in the gammaD crystallin gene. Here we provide a molecular basis for lens opacity in two genetic cataracts and suggest that the opacity occurs because of the spontaneous crystallization of the mutant proteins. Such crystallization of endogenous proteins leading to pathology is an unusual event. Measurements of the solubility curves of crystals of the Arg-58 to His and Arg-36 to Ser mutants of gammaD crystallin show that the mutations dramatically lower the solubility of the protein. Furthermore, the crystal nucleation rate of the mutants is enhanced considerably relative to that of the wild-type protein. It should be noted that, although there is a marked difference in phase behavior, there is no significant difference in protein conformation among the three proteins.

Defibrillation via the elimination of spiral turbulence in a model for ventricular fibrillation

Ventricular fibrillation, the major reason behind sudden cardiac death, is turbulent cardiac electrical activity in which rapid, irregular disturbances in the spatiotemporal electrical activation of the heart make it incapable of any concerted pumping action. Methods of controlling ventricular fibrillation include electrical defibrillation as well as injected medication. Electrical defibrillation, though widely used, involves subjecting the whole heart to massive, and often counterproductive, electrical shocks. We propose a defibrillation method that uses a very low-amplitude shock (of order mV) applied for a brief duration (of order 100 ms) and over a coarse mesh of lines on our model ventricle.

PANORAMA: an integrated Web-based sequence analysis tool and its role in gene discovery

As the exponential growth of DNA sequence information in databases continues, the task of converting this deposited information into knowledge becomes more dependent on integrative sequence analysis and visualization tools. PANORAMA is an Internet-accessible software package that performs a variety of informatics analyses on a given DNA sequence and returns a visual and interactive representation of the results. Its design is modular, so that further sequence analysis tools can be integrated with minimal effort. The utility of PANORAMA is demonstrated in the analysis of 650 kb of human genomic DNA from chromosome region 3p21.3, a region of potential tumor suppressor genes involved in lung cancer, breast cancer, and other forms of cancer. PANORAMA aided in the discovery of genes and alternate splice forms of known exons, in the demarcation of intron-exon boundaries, and in the identification of promoter regions and polymorphisms, all of which contributed to a better understanding of the region. PANORAMA is available on the World Wide Web at http://atlas.swmed.edu.

Spatiotemporal chaos and nonequilibrium transitions in a model excitable medium

We present a detailed study of the statistical steady states of a model for CO oxidation on Pt(110) proposed by Bar and co-workers. We show that the stability diagram of this model depends sensitively on the boundary conditions. We elucidate several novel properties of a state with meandering spirals (M) briefly mentioned by Bar and co-workers. (1) We show that, with periodic boundary conditions, M is the state MP, a binary mixture displaying a coexistence of quasiperiodically rotating spirals and chaotically moving pointlike defects. We show that the transition from MP to the turbulent state T1 is continuous; the transition line marks the locus where the two phases cease to be distinct. (2) With Neumann boundary conditions M is the state MN, a single quasiperiodically rotating spiral. We show that the MN-T1 transition is discontinuous or first order. We also characterize the transitions from MP and MN to the state S, which has quasiperiodically rotating spirals. We also propose qualitative mechanisms for these transitions.

Molecular basis of a progressive juvenile-onset hereditary cataract

In a recent paper, patients with a progressive juvenile-onset hereditary cataract have been reported to have a point mutation in the human gammaD crystallin gene (Stephan, D. A., Gillanders, E., Vanderveen, D., Freas-Lutz, D., Wistow, G., Baxevanis, A. D., Robbins, C. M., VanAuken, A., Quesenberry, M. I., Bailey-Wilson, J., et al. (1999) Proc. Natl. Acad. Sci. USA 96, 1008-1012). This mutation results in the substitution of Arg-14 in the native protein by a Cys residue. It is not understood how this mutation leads to cataract. We have expressed recombinant wild-type human gammaD crystallin (HGD) and its Arg-14 to Cys mutant (R14C) in Escherichia coli and show that R14C forms disulfide-linked oligomers, which markedly raise the phase separation temperature of the protein solution. Eventually, R14C precipitates. In contrast, HGD slowly forms only disulfide-linked dimers and no oligomers. These data strongly suggest that the observed cataract is triggered by the thiol-mediated aggregation of R14C. The aggregation profiles of HGD and R14C are consistent with our homology modeling studies that reveal that R14C contains two exposed cysteine residues, whereas HGD has only one. Our CD, fluorescence, and differential scanning calorimetric studies show that HGD and R14C have nearly identical secondary and tertiary structures and stabilities. Thus, contrary to current views, unfolding or destabilization of the protein is not necessary for cataractogenesis.

Computerized polymorphic marker identification: experimental validation and a predicted human polymorphism catalog

A computational system for the prediction of polymorphic loci directly and efficiently from human genomic sequence was developed and verified. A suite of programs, collectively called POMPOUS (polymorphic marker prediction of ubiquitous simple sequences) detects tandem repeats ranging from dinucleotides up to 250 mers, scores them according to predicted level of polymorphism, and designs appropriate flanking primers for PCR amplification. This approach was validated on an approximately 750-kilobase region of human chromosome 3p21.3, involved in lung and breast carcinoma homozygous deletions. Target DNA from 36 paired B lymphoblastoid and lung cancer lines was amplified and allelotyped for 33 loci predicted by POMPOUS to be variable in repeat size. We found that among those 36 predominately Caucasian individuals 22 of the 33 (67%) predicted loci were polymorphic with an average heterozygosity of 0.42. Allele loss in this region was found in 27/36 (75%) of the tumor lines using these markers. POMPOUS provides the genetic researcher with an additional tool for the rapid and efficient identification of polymorphic markers, and through a World Wide Web site, investigators can use POMPOUS to identify polymorphic markers for their research. A catalog of 13,261 potential polymorphic markers and associated primer sets has been created from the analysis of 141,779,504 base pairs of human genomic sequence in GenBank. This data is available on our Web site (pompous.swmed.edu) and will be updated periodically as GenBank is expanded and algorithm accuracy is improved.

ZFX and ZFY loci in water buffalo (Bubalus bubalis): potential for sex identification

In the present study a small region of ZFX and ZFY loci in buffalo have been amplified by polymerase chain reaction (PCR). Restriction fragment length polymorphism (RFLP) was also uncovered that can distinguish between male and female buffalo DNA. The study also found a second copy of the ZFX loci (ZFXR) present in both male and female. Sequence analysis showed that ZFXR has a single base deletion that results in a redundant putative protein.

Drug use in Nepal: the view from the street

This study uses qualitative research techniques to examine heroin use in Nepal. It explores the life histories of 16 heroin users in Kathmandu, the country's capital, emphasizing those who are street children or who are otherwise displaced. The cases document that the initiation of use in Nepal is a complex process which includes: certain personality traits; an early history of culturally acceptable use of alcohol, tobacco, marijuana, or hashish; peer influence; and the specific social setting of users. Outside (i.e., foreign) influences are included in the mix, but never as a single determinant of drug use. Factors specific to the Nepali scene include the traditional association of forms of marijuana with certain religious contexts and the availability of heroin. An additional factor is the poverty of the urban setting. The approach in Nepal to dealing with drugs primarily involves a realization of the role played by the interaction between personality and social setting in the fullest meaning of that term.

Coronary angioplasty for the control of intractable ventricular arrhythmia

Ventricular arrhythmias (VAs) that occur following an acute extensive anterior myocardial infarction (MI) usually respond to conventional antiarrhythmic regimes of treatment. Rarely, the VA may prove intractable to therapy. This report is of three patients who presented at varying time frames (3 h to 10 weeks) following an anterior MI. They exhibited sustained monomorphic ventricular tachycardia and hemodynamic instability despite multiple antiarrhythmic drug therapy, intravenous magnesium, direct-current cardioversion (DCCV), overdrive pacing (in one case), and intra-aortic balloon counterpulsation (IABP). Although there was no clinical evidence of continuing ischemia and although coronary angiography that was done in each case showed the infarct-related artery (IRA) to subtend akinetic areas on left ventricular (LV) angiogram, percutaneous transluminal coronary angioplasty (PTCA) of the IRA was done in all three cases. Reestablishing patency of the IRA helped in controlling the VA dramatically with average therapeutic doses of antiarrhythmic drugs. All three patients showed this control to have been maintained over a follow-up period of more than 1 year, with partial improvement in LV function and signal-averaged electrocardiogram negative for late potentials. Thus, in patients with extensive infarction and intractable VA, PTCA of the IRA may provide control of VA even in the absence of clinical signs of active ischemia or viable muscle mass.

Increased evening activation of the hypothalamic-pituitary-adrenal axis in depressed patients

OBJECTIVE

To determine whether depressed patients demonstrate hypothalamic-pituitary-adrenal (HPA) axis activation during the late afternoon and evening, a time when the HPA axis is usually quiescent in normal subjects.

METHODS

We administered metyrapone, an 11-beta-hydroxylase inhibitor of cortisol synthesis, to normal controls and depressed patients between 4 and 10 PM. Metyrapone blockade of cortisol secretion would amplify any HPA axis secretion.

RESULTS

In 10 normal control subjects, administration of metyrapone lowered plasma cortisol levels to a mean of 36 nmol/L. No rebound corticotropin or beta-endorphin secretion was seen in these normal controls between 4 and 10 PM, supporting the existence of a period of minimal endogenous corticotropin releasing factor drive. Compared with a group of placebo-treated depressed patients (n = 10), metyrapone-treated depressed subjects (n = 17) had significantly decreased plasma cortisol concentrations. However, in contrast to normal controls treated with metyrapone, metyrapone-treated depressed patients demonstrated rebound corticotroph secretion, particularly between 7:30 and 10 PM (P = .036 for patients vs normal controls for beta-endorphin secretion from 4:30 to 10 PM).

CONCLUSION

These data support the hypothesis of increased corticotropin releasing factor drive in the evening in depressed subjects and are in agreement with the longstanding observation of "early escape" from dexamethasone suppression between 4 and 11 PM in depressed patients.

A longitudinal evaluation of dexamethasone pharmacokinetics in depressed patients and normal controls

Ten depressed patients and eight control subjects received 1 mg of dexamethasone intravenously at two different time points. Depressed patients were studied when they were depressed and following an improvement in their depression. In control subjects the first and second studies were performed approximately 1 month apart. Dexamethasone and cortisol were determined at 0, 5, 15, and 30 minutes, then at 1, 1.2, 2, 3, 4, 5, 6, 7, 9, 12, 17, and 24 hours following dexamethasone administration. Data from each patient was fit using a computer to a two compartment pharmacokinetic model and area under the time versus plasma concentration curve, elimination half-life, and clearance were also determined. Depressed patients exhibited a slower dexamethasone clearance and a larger area under the curve than control subjects at the first time point, but not at the second time point. The groups did not differ significantly in any of the other pharmacokinetic parameters (including distribution half-life, elimination half-life, or volume of distribution) at either time point. The possible causes and implications of these findings are discussed.

Intermolecular protein interactions in solutions of calf lens alpha-crystallin. Results from 1/T1 nuclear magnetic relaxation dispersion profiles

From analyses of the magnetic field dependence of 1/T1 (NMRD profiles) of water protons in solutions of calf lens alpha-crystallin at several concentrations, we find two regimes of solute behavior in both cortical and nuclear preparations. Below approximately 15% vol/vol protein concentration, the solute molecules appear as compact globular proteins of approximately 1,350 (cortical) and approximately 1,700 (nuclear) kD. At higher concentrations, the effective solute particle size increases, reversibly, as evidenced by the appearance of spectra-like 14N peaks in the NMRD profiles and a change in the field and temperature dependence of 1/T1. At these higher concentrations, the profiles are very similar to those of calf gamma II-crystallin, a crystallin that undergoes an analogous transition near approximately 15% protein (Koenig, S. H., C.F. Beaulieu, R. D. Brown III, and M. Spiller, 1990. Biophys. J. 57:461-469). By comparison with recent analyses of NMRD results for solutions of immobilized proteins as models for the transition from protein solutions to tissue (Koenig, S. H., and R. D. Brown III. 1991. Prog. NMR Spectr. 22:487-567), we argue that alpha-crystallin solute behaves as aggregates approximately greater than 50,000 kD as protein concentration is progressively increased above 15%. Finally, the concentration dependence of the NMRD profiles of alpha- and gamma II-crystallin can readily explain recent osmotic pressure data, in particular the intersection of the respective pressure curves at approximately 23% vol/vol (Vérétout, F., and A. Tardieu. 1989. Eur. Biophys. J. 17:61-68).

An Indian hospital study of viral causes of acute respiratory infection in children

From Sept. 1986 to Jan. 1989, a hospital-based study was conducted on 736 children, under 5 years of age, with acute respiratory infection. Nasopharyngeal secretions were examined for viruses by culture and by immunofluorescence. Viruses were detected in 22% of specimens: respiratory syncytial (5%), parainfluenza (5%), influenza A (4%), influenza B (2%), adenovirus (3%), measles (3%). The highest rates of detection were with patients diagnosed clinically as pneumonia or upper respiratory tract infection. The case fatality rate was very high (43%) in children with measles virus infection.

A longitudinal evaluation of dexamethasone and cortisol plasma concentrations in the dexamethasone suppression test before and during treatment with antidepressant drugs

Thirty depressed in- and outpatients received serial dexamethasone suppression tests (DSTs). Plasma dexamethasone and cortisol concentrations were drawn at 1600 on the day following a 1-mg oral dose of dexamethasone. The first DST was performed after patients were drug-free for a period of 1 week; the second, third, and fourth DSTs while patients received antidepressant medication. Dexamethasone and cortisol concentrations drawn in the drug-free period correlated significantly. The cortisol to dexamethasone ratio changed significantly with time in DST nonsuppressors, suggesting that nonsuppression is associated with an altered pharmacodynamic response of the hypothalamopituitary-adrenal axis to dexamethasone during depression. When dexamethasone concentrations from the drug-free period were compared with those drawn during antidepressant treatment, no significant differences were noted.

Prevalence of parainfluenza type 1 virus in Lucknow (India)

A total of 568 children suffering from acute respiratory infections were studied from September, 1986 to June, 1988 using indirect immunofluorescence technique to know the frequency of infections caused by parainfluenza viruses 1 and 3. Though sporadic cases of parainfluenza 1 (2.5%) and parainfluenza 3 (3.2%) were seen round the year, and increase in cases of parainfluenza virus type 1 infection was observed only in October, 1987 in Lucknow.

Viral aetiology of acute respiratory infections in children in north India

Two hundred and thirty children clinically diagnosed as suffering from acute respiratory infection were tested for four major groups of viral aetiological agents, i.e. influenza para-influenza, respiratory syncytial virus (RSV) and adenoviruses using indirect immunofluorescence technique. At least one of the respiratory viruses was identified in 51 (22 per cent) specimens, which included influenza A in 6 (3 per cent), influenza B in 3 (1 per cent), para-influenza type 1 in 3 (1 per cent), para-influenza type 3 in 13 (6 per cent), RSV in 11 (5 per cent) adenovirus in 12 (5 per cent), and dual virus infections in 3 (1 per cent) cases. Maximum number of virus identification was noted in children below 1 year of age, particularly infection with RSV followed by para-influenza and adenoviruses. Value of rapid diagnosis by indirect immunofluorescence technique is stressed.