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71.
72.

Background

The extension of sepsis encompassing the preterm newborn’s brain is often overlooked due to technical challenges in this highly vulnerable population, yet it leads to substantial long-term neurodevelopmental disabilities. In this study, we demonstrate how neonatal neuroinflammation following postnatal E. coli lipopolysaccharide (LPS) exposure in rat pups results in persistent reduction in sialylation of cerebral glycoproteins.

Methods

Male Sprague-Dawley rat pups at postnatal day 3 (P3) were injected in the corpus callosum with saline or LPS. Twenty-four hours (P4) or 21?days (P24) following injection, brains were extracted and analyzed for neuraminidase activity and expression as well as for sialylation of cerebral glycoproteins and glycolipids.

Results

At both P4 and P24, we detected a significant increase of the acidic neuraminidase activity in LPS-exposed rats. It correlated with significantly increased neuraminidase 1 (Neu1) mRNA in LPS-treated brains at P4 and with neuraminidases 1 and 4 at P24 suggesting that these enzymes were responsible for the rise of neuraminidase activity. At both P4 and P24, sialylation of N-glycans on brain glycoproteins decreased according to both mass-spectrometry analysis and lectin blotting, but the ganglioside composition remained intact. Finally, at P24, analysis of brain tissues by immunohistochemistry showed that neurons in the upper layers (II–III) of somatosensory cortex had a reduced surface content of polysialic acid.

Conclusions

Together, our data demonstrate that neonatal LPS exposure results in specific and sustained induction of Neu1 and Neu4, causing long-lasting negative changes in sialylation of glycoproteins on brain cells. Considering the important roles played by sialoglycoproteins in CNS function, we speculate that observed re-programming of the brain sialome constitutes an important part of pathophysiological consequences in perinatal infectious exposure.
  相似文献   
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Recent reports show strikingly high prevalence of diabetes among urban Asian Indians; however, there are very few studies comparing urban, peri-urban and rural prevalence rates of diabetes and their risk factors at the national level. This study is a part of the national non-communicable diseases (NCD) risk factor surveillance conducted in different geographical locations (North, South, East, West/Central) in India between April 2003 and March 2005. A total of 44,523 individuals (age: 15-64 years) inclusive of 15,239 from urban, 15,760 from peri-urban/slum and 13,524 from rural areas were recruited. Major risk factors were studied using modified WHO STEPS approach. Diabetes was diagnosed based on self-reported diabetes diagnosed by a physician. The lowest prevalence of self-reported diabetes was recorded in rural (3.1%) followed by peri-urban/slum (3.2%) and the highest in urban areas (7.3%, odds ratio (OR) for urban areas: 2.48, 95% confidence interval (CI): 2.21-2.79, p<0.001). Urban residents with abdominal obesity and sedentary activity had the highest prevalence of self-reported diabetes (11.3%) while rural residents without abdominal obesity performing vigorous activity had the lowest prevalence (0.7%). In conclusion, this nation-wide NCD risk factor surveillance study shows that the prevalence of self-reported diabetes is higher in urban, intermediate in peri-urban and lowest in rural areas. Urban residence, abdominal obesity and physical inactivity are the risk factors associated with diabetes in this study.  相似文献   
75.
Marked peritubular capillary basement membrane (PTCBM) multilayering, the ultrastructural feature of chronic antibody-mediated rejection (ABMR) of kidney allografts, was found to correspond histologically to PTCs with thickened BMs; such PTCs have been suggested as a novel histological marker of chronic rejection. We investigated whether scoring of PTCBM thickening can substitute the ultrastructural search for PTCBM multilayering. The thickening was graded in PAS- and Jones-stained sections in 110 biopsies from recipients with a late dysfunction, all examined ultrastructurally for transplant capillaropathy (≥3 PTCs with ≥5 BM layers). Grade 0 indicated no thickening. Grade 1 and grade 2 were assigned when the PTCBMs were as thick as or thicker than those of the non-atrophic tubules, and duplication/chain-like lamination of the PTCBM was noted in ≤3 or ≥4 high-power fields, respectively. The series was enrolled in subgroups of those with and those without histopathological lesions of chronic rejection. Fifty-six biopsies displayed lesions of chronic ABMR. Transplant capillaropathy was demonstrated in 40 biopsies. Grade 2 thickening furnished a substantial interobserver concordance rate (κ = 0.803) and correlated with the transplant capillaropathy. Jones staining performed somewhat better in scoring than PAS staining. Grade 2 thickening was verified in 35 biopsies involving chronic ABMR, and in one control biopsy (sensitivity 61.4%, specificity 0.98). Grade 1 thickening was not suggestive of chronic ABMR at all. In conclusion, grade 2 thickening can be regarded as the histopathological lesion of chronic ABMR; however, electron microscopy remains the gold standard in the assessment of PTCBM changes.  相似文献   
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Epilepsy is a multifaceted chronic disorder which has diverse and complex effects on the well-being of the patient. Although it is evident that seizure type and frequency play a critical role in the quality of life (QOL) of patients with epilepsy, it is less clear what the major determinants are that influence QOL in seizure-free patients receiving monotherapy. The aim of this study was to evaluate demographic, clinical, and socioeconomic factors influencing the QOL of seizure-free patients receiving monotherapy. All participants were patients from four medical centers who had epilepsy, were on monotherapy, and had been seizure-free for at least 1 year. Responders completed three questionnaires on demographic and clinical information, QOL, and antiepileptic drug (AED) side effects during routine follow-up visits in the epilepsy clinics. We present the data of 103 patients: 59 females (57.3%), mean age 37.75+/-13.66 years. Treatment side effects and unemployment (p<0.0001, p=0.037, respectively) were significant predictors for poor overall QOL, whereas age, gender, education, family status, comorbidity, seizure type, age of seizure onset, and epilepsy duration did not significantly affect overall QOL. There was no significant difference in side effects and QOL between patients receiving older versus newer AEDs. Ninety-four (92.2%) patients reported experiencing at least one side effect of AEDs when queried about specific symptoms, while only 11 (10.7%) patients replied affirmatively when asked whether they experienced "any" side effects. The most common side effects involved the central nervous system. In conclusion, this study reveals that the most significant factor influencing the QOL in seizure-free patients on monotherapy is AED side effects. QOL is a crucial component in the clinical care of patients with epilepsy, and physicians should take the time to ask specific questions on side effects of AEDs.  相似文献   
79.
In the present study, hepatoprotective effect of Cassia fistula fruit extract was investigated in mice. Animals were divided into six groups receiving normal saline (1), bromobenzene (460 mg/kg) alone (2) and together with increasing doses (200, 400, 600, 800 mg/kg) of a crude hydro-alcoholic extract of Cassia fistula fruit (3-6, respectively). All administrations were carried out orally, daily, for 10 days. On the 11th day, animals were sacrificed. Serum activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and gamma glutamyl transpeptidase (γGT) were determined; serum levels of direct and total bilirubin were measured; furthermore, livers were prepared for histological examination. Our results showed that bromobenzene treatment alone elicited a significant increase in activities of AST, ALT, ALP (but not γGT), and it significantly elevated the levels of direct and total bilirubin. Co-treatment with Cassia fistula fruit extract, however, significantly and dose-dependently decreased the above-mentioned enzyme activities (with exception of γGT) and bilirubin levels, producing a recovery to the naive state. The protective effect of Cassia fistula fruit extract against liver injury evoked by bromobenzene was confirmed by histological examination as well. In conclusion, the Cassia fistula fruit extract has significant hepatoprotective effect in our murine model.  相似文献   
80.
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