Striated Rootlet and Nonfilamentous Forms of Rootletin Maintain Ciliary Function

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Reactivity study of arene(azido)ruthenium N∩O-base complexes with activated alkynes

Substitution reaction of chloro η⁶-arene ruthenium N∩O-base complexes [(η⁶-arene)Ru(N∩O)Cl] [N∩O = pyrazine-2-carboxylic acid (pca-H), 8-hydroxyquinoline (hq-H); arene = p-ⁱPrC₆H₄Me, N∩O = hq (1); arene = C₆Me₆, N∩O = hq (2)] with NaN₃ yield the neutral arene ruthenium azido complexes of the general formula [(η⁶-arene)Ru(N∩O)N₃] [N∩O = pca, arene = p-ⁱPrC₆H₄Me (3), arene = C₆Me₆ (4); N∩O = hq, arene = p-ⁱPrC₆H₄Me (5), arene = C₆Me₆ (6)]. These complexes undergo [3 + 2] dipolar cycloaddition reaction with activated alkynes dimethyl and diethyl acetylenedicarboxylates to yield the arene triazole complexes [(η⁶-arene)Ru(N∩O){N₃C₂(CO₂R)₂}] [N∩O = pca, R = Me, arene = p-ⁱPrC₆H₄Me (7), C₆Me₆ (8); R = Et, arene = p-ⁱPrC₆H₄Me (9), C₆Me₆ (10); N∩O = hq, R = Me, arene = p-ⁱPrC₆H₄Me (11) C₆Me₆ (12); R = Et, arene = p-ⁱPrC₆H₄Me (13), C₆Me₆ (14)]. On the bases of proton NMR study, in the above triazole complexes N(2) isomers are assigned with dimethylacetylenedicarboxylate whereas N(1) isomers with diethylacetylenedicarboxylate. All complexes have been characterized by IR and NMR spectroscopy as well as by elemental analysis. The molecular structures of the azido complexes [(η⁶-p-ⁱPrC₆H₄Me)Ru(pca)N₃] (3), [(η⁶-p-ⁱPrC₆H₄Me)Ru(hq)N₃] (5) and [(η⁶-C₆Me₆)Ru(hq)N₃] (6) have been established by single crystal X-ray diffraction studies.     

The IL1alpha-S100A13 heterotetrameric complex structure: a component in the non-classical pathway for interleukin 1alpha secretion

Interleukin 1α (IL1α) plays an important role in several key biological functions, such as angiogenesis, cell proliferation, and tumor growth in several types of cancer. IL1α is a potent cytokine that induces a wide spectrum of immunological and inflammatory activities. The biological effects of IL1α are mediated through the activation of transmembrane receptors (IL1Rs) and therefore require the release of the protein into the extracellular space. IL1α is exported through a non-classical release pathway involving the formation of a specific multiprotein complex, which includes IL1α and S100A13. Because IL1α plays an important role in cell proliferation and angiogenesis, inhibiting the formation of the IL1α-S100A13 complex would be an effective strategy to inhibit a wide range of cancers. To understand the molecular events in the IL1α release pathway, we studied the structure of the IL1α-S100A13 tetrameric complex, which is the key complex formed during the non-classical pathway of IL1α release.     

Biocatalyst behavior under self-induced electrogenic microenvironment in comparison with anaerobic treatment: evaluation with pharmaceutical wastewater for multi-pollutant removal

Biocatalyst behavior was comparatively evaluated under diverse microenvironments viz., self-induced electrogenic (bioelectrochemical treatment, BET) and anaerobic treatment (AnT) microenvironments, with real-field pharmaceutical wastewater. Relatively higher treatment efficiency was observed with BET (COD removal, 78.70%) over AnT (32%) along with the power output. Voltammetric profiles of AnT showed persistent reduction behavior, while BET depicted simultaneous redox behavior. BET operation documented significantly higher bio-electrocatalytic activity (k_app, 245.22 s⁻¹) than AnT (k_app, 7.35 s⁻¹). The electron accepting conditions due to the presence of electrode in the BET might contributed to higher electrogenesis leading to enhanced substrate degradation along with the removal of multiple pollutants accounting for the effective reduction of toxicity levels of wastewater. Even at higher organic loads, BET operation showed good treatment efficiency without process inhibition. Introduction of electrode-membrane assembly in anaerobic microenvironment showed significant change in the electrocatalytic behavior of biocatalyst resulting in enhanced treatment of complex wastewater.     

Impaired miR-146a expression links subclinical inflammation and insulin resistance in Type 2 diabetes

Molecular and Cellular Biochemistry - Type 2 diabetes patients exhibit subclinical inflammation but the regulatory mechanisms are poorly understood. We sought to evaluate the role of miR-146a...     

Natural attenuation of endocrine-disrupting estrogens in an ecologically engineered treatment system (EETS) designed with floating, submerged and emergent macrophytes

Natural attenuation of estrogenic endocrine disrupting compounds (EDCs) such as estriol (E3, natural) and 17α-ethinylestradiol (EE2, synthetic) were evaluated in a designed ecologically engineered treatment system (EETS) along with domestic sewage. These two estrogens are the major contaminants of sewage and found to cause adverse effects on the endocrine system of humans and animals when exposed even in nanogram concentrations. The EETS consisted of three tanks containing diverse biota, viz., aquatic macrophytes, submerged plants, emergent plants, algae and bacteria present in the system mimic the natural cleansing functions of wetlands and help in the treatment of pollutants present in wastewater. During operation, 22 μg/l of E3 and EE2 were separately fed for 10 days each and operated in continuous mode (20 l/day). The floating macrophytes system (Tank 1) was more effective in removing estrogens [E3 - 61.77% (13.59 μg/l); EE2 - 69.09% (15.20 μg/l)] compared to the submerged-emergent macrophytes-based integrated system (Tank 2) [E3 - 16.58% (3.65 μg/l); EE2 - 18.52% (4.08 μg/l)] and submerged-rooted microphytes system (Tank 3) [E3 - 15.20%, (3.35 μg/l); EE2 - 7.72%, (1.70 μg/l)]. On the whole, EETS can effectively treat EDCs [E3 93.56% (20.59 μg/l); EE2 95.34% (20.97 μg/l)]. Removal of COD (68.06%), nitrates (60.02%) and turbidity (83.43%) was also observed simultaneously during EETS operation. The designed EETS is ecologically complex and mechanically simple and has very low energy consumption and function based on a natural cleansing mechanism (attenuation) with esthetic value.     

Susceptibility to intestinal tumorigenesis in folate-deficient mice may be influenced by variation in one-carbon metabolism and DNA repair

Low dietary folate is associated with increased risk of colorectal cancer. In earlier work, we showed that folate deficiency induced intestinal tumors in BALB/c but not C57Bl/6 mice through increased dUTP incorporation into DNA with consequent DNA damage. To determine whether strain differences between one-carbon metabolism and DNA repair pathways could contribute to increased tumorigenesis in BALB/c mice, we measured amino acids and folate in the normal intestinal tissue of both strains fed a control diet or a folate-deficient diet. We also determined the expression of critical folate-metabolizing enzymes and several DNA repair enzymes. BALB/c mice had lower intestinal serine (major cellular one-carbon donor), methionine and total folate than C57Bl/6 mice under both dietary conditions. BALB/c mice had higher messenger RNA and protein levels of three folate-interconverting enzymes: trifunctional methyleneTHF (5,10-methylenetetrahydrofolate) dehydrogenase–methenylTHF cyclohydrolase–formylTHF (10-formyltetrahydrofolate) synthetase 1, bifunctional methyleneTHF dehydrogenase–methenylTHF cyclohydrolase and methylenetetrahydrofolate reductase. This pattern of expression could limit the availability of methyleneTHF for conversion of dUMP to dTMP. BALB/c mice also had higher levels of uracil DNA glycosylase 2 protein without an increase in the rate-limiting DNA polymerase β enzyme, compared with C57Bl/6 mice. We conclude that BALB/c mice may be more prone to DNA damage through decreased amounts of one-carbon donors and the diversion of methyleneTHF away from the conversion of dUMP to dTMP. In addition, incomplete excision repair of uracil in DNA could lead to accumulation of toxic repair intermediates and promotion of tumorigenesis in this tumor-susceptible strain.