Subgenotypes of hepatitis B virus genotype D (D1, D2, D3 and D5) in India: differential pattern of mutations, liver injury and occult HBV infection

Hepatitis B genotype D (HBV/D) is the most widespread genotype and exists as at least five subgenotypes (HBV/D1-D5). However, little is known about the association of virological characteristics with clinical differences among HBV/D subgenotypes. To investigate the virological characteristics of these subgenotypes and their clinical implications, we selected a cohort of 109 genotype D infected individuals from the state of West Bengal, India, including 68 HBsAg positive patients and 41 with occult HBV infection. Among the HBsAg positive subjects 28 had chronic hepatitis B virus infection, 40 were asymptomatic carriers based on clinical examination, liver function test and ultrasonograph results. Overall, HBV/D1 was found in 17%, HBV/D2 in 29%, HBV/D3 in 34% and HBV/D5 in 20% of the cases. HBV/D1 was significantly associated with chronic liver disease (P = 0.01), and in this subgenotype A1896 (PreC mutations) were most common. Although BCP mutations (A/C1753 and T1762/A1764) were found to be frequently associated with HBV/D2 (33% and 33%) and D5 (47% and 59%), no apparent clinical correlation was observed. On the other hand, occult HBV infection was significantly associated with HBV/D3 infection, along with low level of BCP and PreC mutations and several non-synonymous substitutions in the catalytic reverse transcriptase (RT) domain of polymerase gene. Similar nucleotide substitutions in the surface (S) gene region were observed from both northern and eastern Indian HBV/D3 isolates. In conclusion, HBV/D subgenotypes differ in their mutational patterns in the S, polymerase and the BCP/PreC regions that may influence their clinical outcomes.

Intrinsic tunneling in phase separated manganites

We present evidence of direct electron tunneling across intrinsic insulating regions in submicrometer wide bridges of the phase-separated ferromagnet (La,Pr,Ca)MnO3. Upon cooling below the Curie temperature, a predominantly ferromagnetic supercooled state persists where tunneling across the intrinsic tunnel barriers (ITBs) results in metastable, temperature-independent, high-resistance plateaus over a large range of temperatures. Upon application of a magnetic field, our data reveal that the ITBs are extinguished resulting in sharp, colossal, low-field resistance drops. Our results compare well to theoretical predictions of magnetic domain walls coinciding with the intrinsic insulating phase.

Quantitation of proteinuria in nephrotic syndrome by spot urine protein creatinine ratio estimation in children

In Nephrotic Syndrome the amount of protein excretion is a reflection of activity of disease. Quantitative measurement of proteinuria by a 24-hour urine collection has been the accepted method of evaluation. Recent studies have shown that calculation of protein/creatinine ratio in a spot urine sample correlates well with the 24-hour urine protein (24-HUP) excretion. A study was conducted to compare the accuracy of a spot urinary protein/creatinine ratio (P/C ratio) and urinary dipstick with the 24-hour urine protein. Fifty two samples from 26 patients of nephrotic syndrome were collected. This included a 24-hour urine sample followed by the next voided random spot sample. The protein/creatinine ratio was calculated and dipstick was performed on the spot sample. This was compared with the 24-hour urine protein excretion. The correlation between the three samples was statistically highly significant (p<0.001) for all levels of proteinuria. The normal value of protein/creatinine ratio in Indian children was also estimated on 50 normal children admitted in the ward without any renal diseases calculated to be 0.053 (SE of mean+/-0.003).

An investigation into a mass psychogenic illness at Burdwan, West Bengal

This investigation of the outbreak of mass psychogenic illness during July 2007 at three schools in Burdwan was done to observe the description of the epidemic, identify its characteristics and to study any particular factor associated with the spread of illness. Relevant data were obtained from medical and school records. All concurrent factors were considered. All the incidents happened prior to the examinations. There have been differences in presentations and final diagnosis among the schools. Intense media coverage influenced the manifestations. Poor school performance was associated with recurrence of symptoms. So understanding the academic anxiety is important to prevent such outbreaks.

Refining quantitative fluorescent polymerase chain reaction for prenatal detection of X chromosomal anomalies in the major Southeast Asian populations

INTRODUCTION

This study aimed to refine the current quantitative fluorescent polymerase chain reaction (QF-PCR) screen to detect X chromosome anomalies for prenatal diagnosis in the major Southeast-Asian populations.

METHODS

100 amniotic fluid samples from Chinese, Malay and Indian origins were subjected to QF-PCR using the X chromosome markers, HPRT, X22 and AMXY, along with the autosomal marker D21S1411.

RESULTS

Out of the 100 samples tested by markers X22 and HPRT, eight samples were homozygous for both markers, of which seven were resolved by comparison with the autosomal marker D21S1411.

CONCLUSION

99 percent of samples could be tested for X chromosome copy numbers, increasing the stringency for detection of X chromosome anomalies by QF-PCR. All results were confirmed by cytogenetics.

Prevalence of major neurological disorders among geriatric population in the metropolitan city of Kolkata

Well-conducted neuroepidemiological studies for the geriatric population are rare in India. In view of the growing aging population, we planned to determine the prevalence of common neurological disorders among the elderly population in the city of Kolkata. This was a cross-sectional study of a stratified random sample of the city population and carried in two stages through house to house survey. Initially, trained non-medical workers screened the cases with a validated family questionnaire and then a neurologist examined all the screened positive cases. A validated neuropsychological screening test was also applied among the elderly population with cognitive complaints. Results showed prevalence rates (per 1000 elderly population--> or = 60 years) of following disorders in decreasing order: stroke--33.93, essential tremor--13.76, dementia--7.89, Parkinsonism--3.30 and epilepsy--2.57. Sex-specific prevalence showed that stroke was commoner among men and that of other disorders among women. Age-specific prevalence recorded progressive increase in the rates of all disorders among both genders, though not uniformly among women. Overall the crude prevalence of neurological disorders was 60.9 per 1000. The present study shows higher rate of stroke as compared to other neurological disorders among elderly population in India, which needs urgent attention.

Homozygous alpha-thalassemia in a growth retarded, non-hydropic premature newborn

A newborn with homozygous alpha-thalassemia presented with intrauterine growth retardation and presumed persistent pulmonary hypertension. He also had moderate anemia, hepatomegaly and hypospadias. Correlating the newborn's clinical presentation with an underlying cause of anemia was helpful for early diagnosis. Prenatal blood tests must include red cell indices and a mean corpuscular volume value below 80 fL should prompt thalassemia screening in an at-risk population.

Comparative growth behaviour and characterization of stem cells from human Wharton's jelly

Human embryonic stem cells (hESC) face ethical sensitivities and the problem of teratoma formation. Although Wharton's jelly stem cells (WJSC), also of embryonic origin, may not face such ethical concerns, it is not definitely known whether under hESC culture conditions they would be as pluripotent as hESC. WJSC grown on plastic showed two types of morphology (epithelioid and short fibroblastic) in primary culture depending on the culture medium used, and only fibroblastic morphology when passaged. When grown in the presence of hESC medium on mouse feeder cells, they produced atypical colonies containing hESC-like cells with high-nuclear cytoplasmic ratios and prominent nucleoli. They were positive for the hESC markers Tra-1-60, Tra-1-81, SSEA-1, SSEA-4, Oct-4 and alkaline phosphatase, negative for SSEA-3, showed normal karyotypes, developed embryoid body (EB)-like structures, did not produce teratomas in SCID mice and differentiated into neuronal derivatives. They were also positive for the mesenchymal CD markers (CD105, CD90, CD44), negative for CD34 and HLA, and although nine out of 10 embryonic stem cell genomic markers were detectable, these were expressed at low levels. WJSC are thus not as pluripotent as hESC but widely multipotent, and have the advantages of being able to be scaled up easily and not inducing teratomas.