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121.

Objective

To evaluate the factors associated with low birth weight (LBW) and to formulate a scale to predict the probability of having a LBW infant.

Methods

This hospital based case–control study was conducted in a tertiary care university hospital in North India. The study included 250 LBW neonates and 250 neonates with birth weight ≥2,500 g. Data were collected by interviewing mothers using pre-designed structured questionnaire and from hospital records.

Results

Factors significantly associated with LBW were inadequate weight gain by the mother during pregnancy (<8.9 kg), inadequate proteins in diet (<47 g/d), previous preterm baby, previous LBW baby, anemic mother and passive smoking. The prediction model made on these six variables has a sensitivity of 71.6 %, specificity 67.0 %, positive LR 2.17 and negative LR of 0.42 for a cut-off score of ≥29.25. On validation, it has a sensitivity of 72 % and specificity of 64 %.

Conclusions

It is possible to predict LBW using a prediction model based on significant risk factors associated with LBW.  相似文献   
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125.

Aims/hypothesis

Adult beta cells have a diminished ability to proliferate. Phosphatase and tensin homologue (PTEN) is a lipid phosphatase that antagonises the function of the mitogenic phosphatidylinositol 3-kinase (PI3K) pathway. The objective of this study was to understand the role of PTEN and PI3K signalling in the maintenance of beta cells postnatally.

Methods

We developed a Pten lox/lox; Rosa26 lacZ; RIP-CreER + model that permitted us to induce Pten deletion by treatment with tamoxifen in mature animals. We evaluated islet mass and function as well as beta cell proliferation in 3- and 12-month-old mice treated with tamoxifen (Pten deleted) vs mice treated with vehicle (Pten control).

Results

Deletion of Pten in juvenile (3-month-old) beta cells significantly induced their proliferation and increased islet mass. The expansion of islet mass occurred concomitantly with the enhanced ability of the Pten-deleted mice to maintain euglycaemia in response to streptozotocin treatment. In older mice (>12 months of age), deletion of Pten similarly increased islet mass and beta cell proliferation. This novel finding suggests that PTEN-regulated mechanisms may override the age-onset diminished ability of beta cells to respond to mitogenic stimulation. We also found that proteins regulating G1/S cell-cycle transition, such as cyclin D1, cyclin D2, p27 and p16, were altered when PTEN was lost, suggesting that they may play a role in PTEN/PI3K-regulated beta cell proliferation in adult tissue.

Conclusions/interpretation

The signals regulated by the PTEN/PI3K pathway are important for postnatal maintenance of beta cells and regulation of their proliferation in adult tissues.  相似文献   
126.
Infective endocarditis is extremely rare in children with structurally normal hearts. The most common etiological agents are staphylococcal and streptococcal species. Nutritionally variant streptococci also classified as Abiotrophia species are a group of fastidious organisms that account for only 5% to 6% of all cases of culture‐negative infective endocarditis. Only seven cases of Abiotrophia infective endocarditis have been previously reported in children with no underlying structural heart disease. We report two cases of Abiotrophia infective endocarditis in children without any predisposing factors. Both patients presented with nonspecific symptoms leading to delay in diagnosis. While bacteriological clearance was achieved in both cases, both had a complicated course including development of brain mycotic aneurysms, splenic infarction, renal failure, and irreversible damage to the mitral valve. Both patients required surgical removal of the native mitral valve and replacement. We also present review of seven cases with similar diagnosis published previously in literature and highlight important differences. Our cases highlight special challenges in management of Abiotrophia endocarditis in pediatric patients. As the organism may not be isolated in routine culture media, may present with atypical clinical symptoms and may have a complicated course even without antibiotic failure, a high index of suspicion should be maintained in children with subacute symptoms even with no underlying structural cardiac disease.  相似文献   
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T cell prolymphocytic leukemia (T-PLL) is a rare mature T cell lymphoproliferative disease. It has been associated with an aggressive course, a poor response to conventional chemotherapy and a short median survival. Here we present a rare case of concurrent T-PLL and Kaposi sarcoma who achieved a complete hematologic and cytogenetic remission after a very short course of treatment with alemtuzumab. A review of T-PLL was done. In this review, clinical features, laboratory features and current therapeutic strategies of T-PLL are presented.  相似文献   
130.

Background

Autoantibody testing is used to diagnose autoimmune hepatitis (AIH), a cause of chronic liver disease (CLD). However, various autoantibodies are often detectable in patients with CLD due to other causes too. Since data on autoantibody prevalence in Indian patients with CLD are limited, we decided to undertake the current study.

Methods

Patients with CLD with a known cause other than AIH and a separate group of patients with CLD in whom no cause could be identified were studied. Indirect immunofluorescence assays were used to detect anti-nuclear antibodies (ANA), anti-smooth muscle antibodies (ASMA) and anti-liver-kidney microsomal antibodies (anti-LKM). Serum dilutions tested were 1:80 for ANA and 1:40 for other autoantibodies.

Results

Of the 175 patients with CLD of a known cause, 69 (39?%) had one or more autoantibodies, including ANA in 35 (20?%) patients and ASMA in 44 (25?%) patients. None had anti-LKM. The prevalence rates of any autoantibody, ANA and ASMA were similar in patients with CLD due to alcohol (34?%, 20?%, and 24?%, respectively), HCV infection (43?%, 20?%, and 26?%) and HBV infection (40?%, 18?%, and 25?%). The most common ANA pattern observed was speckled (29/35 patients), followed by nucleolar (5/35) and homogeneous (1/35). The ASMA titers did not exceed 1:80. The antibody prevalence rates were similar in patients with liver cirrhosis and chronic hepatitis, and in those with different disease severity. Serum IgG levels were similar in patients with and without detectable autoantibodies. Patients with no known cause of CLD (n?=?50) had similar prevalence rates of autoantibodies, ANA or ASMA.

Conclusion

Autoantibodies were detected in a large proportion of patients with CLD, both cryptogenic and with known cause. Detection of autoantibodies in CLD does not necessarily indicate a diagnosis of AIH, and presence of homogenous pattern of ANA may be more relevant. Indiscriminate testing for autoantibodies in patients with CLD, especially those with a known cause, may not be warranted.  相似文献   
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