Mechanisms and consequences of TGF-ß overexpression by podocytes in progressive podocyte disease

In patients with progressive podocyte disease, such as focal segmental glomerulosclerosis (FSGS) and membranous nephropathy, upregulation of transforming growth factor-ß (TGF-ß) is observed in podocytes. Mechanical pressure or biomechanical strain in podocytopathies may cause overexpression of TGF-ß and angiotensin II (Ang II). Oxidative stress induced by Ang II may activate the latent TGF-ß, which then activates Smads and Ras/extracellular signal-regulated kinase (ERK) signaling pathways in podocytes. Enhanced TGF-ß activity in podocytes may lead to thickening of the glomerular basement membrane (GBM) by overproduction of GBM proteins and impaired GBM degradation in podocyte disease. It may also lead to podocyte apoptosis and detachment from the GBM, and epithelial-mesenchymal transition (EMT) of podocytes, initiating the development of glomerulosclerosis. Furthermore, activated TGF-ß/Smad signaling by podocytes may induce connective tissue growth factor and vascular endothelial growth factor overexpression, which could act as a paracrine effector mechanism on mesangial cells to stimulate mesangial matrix synthesis. In proliferative podocytopathies, such as cellular or collapsing FSGS, TGF-ß-induced ERK activation may play a role in podocyte proliferation, possibly via TGF-ß-induced EMT of podocytes. Collectively, these data bring new mechanistic insights into our understanding of the TGF-ß overexpression by podocytes in progressive podocyte disease

Role of genetic polymorphisms in tumour angiogenesis

Angiogenesis plays a crucial role in the development, growth and spread of solid tumours. Pro- and anti-angiogenic factors are abnormally expressed in tumours, influencing tumour angiogenesis, growth and progression. Polymorphisms in genes encoding angiogenic factors or their receptors may alter protein expression and/or activity. This article reviews the literature to determine the possible role of angiogenesis-related polymorphisms in cancer. Further research studies in this potentially crucial area of tumour biology are proposed

Electrohydrodynamic atomization (EHDA) of high-conductivity pure solvent

In this study, the effects of flow rate, liquid conductivity and neutralizer strength on the operating and output characteristics are examined for an Electrohydrodynamic atomization (EHDA)-based aerosol generator system, designed and built in our laboratory. Ethylene glycol is used for generating the droplets. It is seen that stable cone-jet mode could be obtained for solvent conductivity as high as 240 S/cm. While the output number concentration was found to increase with both flow rate and conductivity, the mean particle diameters decreased with increasing conductivity and increased with flow rate. The mean droplet size and output number concentration are found to be about three times more sensitive to changes in conductivity as compared to that of flow rate in the range of 26-150 S/cm. It is also observed that throughput from the system is strongly dependent on the strength of the charge neutralizer. In the present setup, 8 Ci Am-241 bipolar neutralizer in axisymmetric configuration was found to be sufficient to neutralize the generated droplets

Low-Scale Foreshore Morphodynamic Processes in the Vicinity of a Tropical Estuary at Honnavar, Central West Coast of India

Low-scale foreshore morphodynamic processes in the vicinity of the Sharavati estuary at Honnavar, central west coast of India, are discussed in this paper based on the wave refraction analyses, sediment characteristics, and foreshore morphological changes. In general, the foreshore is composed of medium- to fine-grained (1.12–2.68), well-sorted to poorly sorted sands (0.18–0.86σ). Beaches experience two periods of accretion, one during September to December (postmonsoon) and another during February to April, followed by two periods of erosion, one during second half of May to early September (monsoon) and another a minor phase of erosion from December to February. The study indicated two distinct trends of geomorphic process on either side of the river mouth. Nearshore coastal process and wind largely control shoreface modification of the beaches to the south of the river mouth, whereas islands in this region modify geomorphic processes of the beach to the north of the river mouth. Northerly drift prevailing during the postmonsoon season favors spit growth across the river mouth from south to north, whereas the southerly drift during December to February is responsible for erosion of the portion of the beach to the north of the river mouth. The growth of a spit is at the expense of the beach to the north of the river mouth. However, during the westerly wave approach (March–April), littoral cells developed in the vicinity of river mouth provided stability to the beach