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Alveolar overdistension during mechanical ventilation causes leukocyte sequestration, leading to lung injury. However, underlying endothelial cell (EC) mechanisms are undefined. In a new approach, we exposed isolated blood-perfused rat lungs to high tidal volume ventilation (HV) for 2 h, then obtained fresh lung endothelial cells (FLEC) by immunosorting at 4 degrees C. Immunoblotting experiments indicated that as compared with FLEC derived from lungs ventilated at low volume (LV), HV markedly enhanced tyrosine phosphorylation (TyrP). The tyrosine kinase blocker, genistein, inhibited this response. HV also induced focal adhesion (FA) formation in FLEC, as detected by immunofluorescent aggregates of the alpha(v)beta(3) integrin that co-localized with aggregations of focal adhesion kinase (FAK). Immunoprecipitation and blotting experiments revealed that HV increased TyrP of the FA protein, paxillin. In addition, HV induced a paxillin-associated P-selectin expression on FLEC that was also inhibited by genistein. However, HV did not increase lung water. These results indicate that in HV, EC signaling in situ causes FA formation and induces TyrP-dependent P-selectin expression. These signaling mechanisms may promote leukocyte-mediated responses in HV.

Background: Timely diagnosis of invasive fungal infections (IFI) in renal transplant (RT) patients on immunosuppression is often difficult, jeopardizing their life and graft. We reported IFI and their causative fungal agents in post-RT patients.Materials and methods: This was a retrospective 6-year clinical study carried out from 2010 to 2015 on 1900 RT patients. Clinical data included patient-donor demographics, time to onset of infection, risk factors and graft function in terms of serum creatinine (SCr). To identify IFI, we examined bronchoalveolar lavage (BAL), blood, tissue, and wound swab samples by conventional mycological methods.Results: IFI were diagnosed in 30 (1.56%) patients on triple immunosuppression, mainly males (n = 25) with mean age of 36.57 ± 11.9 years at 13.12 ± 18.35 months post-RT. Aspergillus species was identified in 11 BAL, one tissue, and one wound specimen each, 30.76% of these were fatal and 15.38% caused graft loss; Candida albicans was in nine BAL, four blood, two wound swab, and one tissue specimens, 25% of these were fatal and 25% had graft loss and one mucor in BAL which was fatal. Seven patients were diabetic, 10 had superadded cytomegalovirus infection, and 15 were anti-rejected.Conclusion: IFI are associated with increased morbidity and mortality in RT patients. Triple immunosuppression, broad spectrum antibiotics for ≥ two weeks, diabetes and superadded infection are added risks for these patients. Prevention, early diagnosis, and appropriate management are necessary to improve their prognosis.

Background:Renal biopsy is a well-established diagnostic modality for the assessment of kidney diseases in children. It can provide diagnostic precision and prognostic value and guide in therapeutic options for many renal diseases.Objectives:This report describes the indication, histopathological patterns, and epidemiology of renal diseases in children in India.Patients and Methods:This is a single-center study on renal biopsies performed between January 2008 and December 2013 in 346 children (age ≤ 14 years).Results:Eleven (3.17%) biopsies were inadequate, and 335 biopsies were considered for analysis. The mean age was 7.91 ± 3.04 years with a predominance of males (68.1%). Nephrotic syndrome (46.2%) was the most common indication, followed by urinary abnormality (41.19%), acute nephritic syndrome (10.74%), and chronic renal failure (1.79 %). Primary glomerulonephritis (GN) was predominant (81.79%), and secondary GN constituted 16.12% of the biopsies. Primary GN included mesangial proliferative GN (MePGN), IgM nephropathy, focal segmental glomerulosclerosis, minimal change disease, IgA nephropathy, membranoproliferative GN, membranous nephropathy, crescentic GN, and post-infectious GN. Secondary GN revealed lupus nephritis, hemolytic uremic syndrome, amyloidosis, and hypertensive nephropathy. Tubulointerstitial nephritis was observed in 2.08%. The most common histological pattern of primary GN was MePGN (20%) and in secondary GN it was lupus nephritis (7.76%).Conclusions:The present study provides data on the epidemiology of renal diseases in children in India and will be helpful for developing a national registry and devising therapeutic guidelines.

Vitronectin, which ligates the alpha(v)beta(3)-integrin, increases both lung capillary permeability and lung endothelial Ca(2+). In stable monolayers of bovine pulmonary artery endothelial cells (BPAECs) viewed with confocal microscopy, multimeric vitronectin aggregated the apically located alpha(v)beta(3)-integrin. This caused arachidonate release that was inhibited by pretreating the monolayers with the anti-alpha(v)beta(3) monoclonal antibody (MAb) LM609. No inhibition occurred in the presence of the isotypic MAb PIF6, which recognizes the integrin alpha(v)beta(5). Vitronectin also caused membrane translocation and phosphorylation of cytosolic phospholipase A(2) (cPLA(2)) as well as tyrosine phosphorylation of the mitogen-activated protein kinase (MAPK) extracellular signal-regulated kinase (ERK) 2. The cPLA(2) inhibitor arachidonyl trifluoromethylketone, the tyrosine kinase inhibitor genistein, and the MAPK kinase inhibitor PD-98059 all blocked the induced arachidonate release. PD-98059 did not inhibit the increase of cytosolic Ca(2+) or cPLA(2) translocation, although it blocked tyrosine phosphorylation of ERK2. Moreover, although the intracellular Ca(2+) chelator MAPTAM also inhibited arachidonate release, it did not inhibit tyrosine phosphorylation of ERK2. These findings indicate that ligation of apical alpha(v)beta(3) in BPAECs caused ERK2 activation and an increase of intracellular Ca(2+), both conjointly required for cPLA(2) activation and arachidonate release. This is the first instance of a tyrosine phosphorylation-initiated "two-hit" signaling pathway that regulates an integrin-induced proinflammatory response.