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Sanjeev Kumar Sharma

Publications and source records attributed to Sanjeev Kumar Sharma.

2 recordsLinked to original sources

Hepatitis B virus: inactive carriers.

Inactive carriers forms the largest group in chronic HBV infected patients. Around 300 million people are inactive carriers The inactive HBsAg carrier state is diagnosed by absence of HBeAg and presence of anti-HBe, undetectable or low levels of HBV DNA in PCR-based assays, repeatedly normal ALT levels, and minimal or no necroinflammation, slight fibrosis, or even normal histology on biopsy. Inactive cirrhosis may be present in patients who had active liver disease during the replicative phase of infection. The prognosis of the inactive HBsAg carrier state is usually benign. Long-term follow- up (up to 18 years) of these carriers has indicated that the vast majority show sustained biochemical remission and very low risk of cirrhosis or hepatocellular carcinoma (HCC). Rarely, patients, even noncirrhotics, may develop liver cancer during the inactive HBsAg carrier state. In addition, approximately 20 to 30% of persons in the inactive HBsAg carrier state may undergo spontaneous reactivation of hepatitis B during follow-up. Multiple episodes of reactivation or sustained reactivation can cause progressive hepatic damage and even hepatic decompensation.

Adult↗

Somatic embryogenesis in Solanum tuberosum L.: a histological examination of key developmental stages.

A potential novel method of producing high-quality potato ( Solanum tuberosum L.) nuclear seeds is through the process of somatic embryogenesis (SE). Somatic embryo formation has been successfully reported in many plant species, but in potato, reliable SE systems are still at the experimental stage. A key factor in the success of any SE system is the ability to discriminate SE-specific cellular structures from those emerging through an organogenic route. In the investigation reported here we attempted to discriminate the progression of specific stages of potato SE by histological means. Internodal segment (INS) explants from 4- to 6-week-old cv. Desiree in vitro cultures were successively cultured on SE induction (for 2 weeks) and expression/regeneration media (for 3 weeks) with and without 2,4-dichlorophenoxyacetic acid (5 microM). Microscopic examination of histological slides prepared using INS explants at different stages revealed the presence of characteristic globular, heart and torpedo stages in the potato SE system along with other associated unique features such as protoderm development and discrete vascular connections. These results confirm the occurrence of potato SE as per the accepted definition of the term.

2,4-Dichlorophenoxyacetic Acid↗