377 research outputs found
Hemiorchidectomy leads to dramatic and immediate alterations in pituitary follicle-stimulating hormone secretion and the functional activity of the remaining testis in the adult male bonnet monkey (Macaca radiata)
The aim of the present study was to examine the effect of hemiorchidectomy (HO) on serum FSH, LH, testosterone (T), and inhibin (INH) concentrations as well as on the testicular volume (TV) and on changes in the kinetics of germ cell turnovers in the remaining testis of adult male bonnet monkeys. Blood samples collected at 2200 h at various times before and after HO and testicular biopsies obtained at different periods were subjected to hormone analysis and DNA flow cytometry. Though serum T levels were lowered (p < 0.05) at 12 h after HO, T levels rapidly returned to intact control concentrations by Day 5. While serum LH remained unaltered, serum FSH increased markedly within 2 days of HO and remained significantly (p < 0.05) elevated over the next 90 days. Though serum INH showed a significant decrease (p < 0.05) by 15 min of HO, it returned to approximately 80% of intact levels within one week. The TV of the remaining testis showed maximal increment by Day 30 (p < 0.05) of HO. DNA flow cytometric analysis 24 days after HO showed increases (p < 0.05) in spermatogonia (2C) and primary spermatocytes (4C). These cell types by Day 45 had transformed to round (1C) and elongate (HC) (by 38%, p < 0.001) spermatids. Overall spermatogenesis (conversion of 2C to 1C and HC) showed significant enhancement at Days 110 and 175, suggesting that the spurt in spermatogenic activity is not confined to a single spermatogenic cycle
Irreversible EGFR Inhibitor EKB-569 Targets Low-LET γ-Radiation-Triggered Rel Orchestration and Potentiates Cell Death in Squamous Cell Carcinoma
EKB-569 (Pelitinib), an irreversible EGFR tyrosine kinase inhibitor has shown potential therapeutic efficiency in solid tumors. However, cell-killing potential in combination with radiotherapy and its underlying molecular orchestration remain to be explored. The objective of this study was to determine the effect of EKB-569 on ionizing radiation (IR)-associated NFκB-dependent cell death. SCC-4 and SCC-9 cells exposed to IR (2Gy) with and without EKB-569 treatment were analyzed for transactivation of 88 NFκB pathway molecules, NFκB DNA-binding activity, translation of the NFκB downstream mediators, Birc1, 2 and 5, cell viability, metabolic activity and apoptosis. Selective targeting of IR-induced NFκB by EKB-569 and its influence on cell-fate were assessed by overexpressing (p50/p65) and silencing (ΔIκBα) NFκB. QPCR profiling after IR exposure revealed a significant induction of 74 NFκB signal transduction molecules. Of those, 72 were suppressed with EKB-569. EMSA revealed a dose dependent inhibition of NFκB by EKB-569. More importantly, EKB-569 inhibited IR-induced NFκB in a dose-dependent manner, and this inhibition was sustained up to at least 72 h. Immunoblotting revealed a significant suppression of IR-induced Birc1, 2 and 5 by EKB-569. We observed a dose-dependent inhibition of cell viability, metabolic activity and apoptosis with EKB-569. EKB-569 significantly enhanced IR-induced cell death and apoptosis. Blocking NFκB improved IR-induced cell death. Conversely, NFκB overexpression negates EKB-569 -induced cell-killing. Together, these pre-clinical data suggest that EKB-569 is a radiosensitizer of squamous cell carcinoma and may mechanistically involve selective targeting of IR-induced NFκB-dependent survival signaling. Further pre-clinical in-vivo studies are warranted
Enhanced susceptibility of follicle-stimulating-hormone-deprived infertile bonnet monkey (Macaca radiata) spermatozoa to dithiothreitol-induced DNA decondensation in situ
Immunoneutralization of endogenous follicle-stimulating hormone (FSH) of adult male monkeys leads to oligospermia and infertility despite unchanged testosterone levels. The inability of these monkeys to impregnate despite repeated exposures to cycling females appeared to be due to abnormal alterations in the kinetics of germ cell transformations and deficient spermiogenesis. Here we investigated the stability of sperm chromatin in oFSH-immunized monkeys as a marker for spermiogenesis. The susceptibility of spermatozoa to in vitro decondensation induced by dithiothreitol (DTT, 0.05-50 mM) was studied by measuring the nuclear fluorescence of DTT-treated, ethidium bromide (EB)-stained sperm using flow cytometry. Changes in sperm morphology and binding of thiol-specific 14C-iodoacetamide (14C-IA) were also monitored under the same conditions. Sperm from the immunized monkeys decondensed at a lower concentration of DTT, bound more EB, and decondensed more extensively than those from control animals. The difference was apparent in sperm from all regions of the epididymis. Immunized monkey sperm also bound significantly more 14C-IA at all concentrations of DTT. Overall, the effective concentration of DTT required to elicit 50% of maximal decondensation (ED50) of epididymal and ejaculated sperm was significantly lower for the immunized monkeys than even the caput sperm of controls. These results suggest that FSH deprivation in monkeys results in production of sperm with limited potential for disulfide formation and reduced chromatin stability
Cardiovascular magnetic resonance guided electrophysiology studies
Catheter ablation is a first line treatment for many cardiac arrhythmias and is generally performed under x-ray fluoroscopy guidance. However, current techniques for ablating complex arrhythmias such as atrial fibrillation and ventricular tachycardia are associated with suboptimal success rates and prolonged radiation exposure. Pre-procedure 3D CMR has improved understanding of the anatomic basis of complex arrhythmias and is being used for planning and guidance of ablation procedures. A particular strength of CMR compared to other imaging modalities is the ability to visualize ablation lesions. Post-procedure CMR is now being applied to assess ablation lesion location and permanence with the goal of indentifying factors leading to procedure success and failure. In the future, intra-procedure real-time CMR, together with the ability to image complex 3-D arrhythmogenic anatomy and target additional ablation to regions of incomplete lesion formation, may allow for more successful treatment of even complex arrhythmias without exposure to ionizing radiation. Development of clinical grade CMR compatible electrophysiology devices is required to transition intra-procedure CMR from pre-clinical studies to more routine use in patients
(3E,5E)-1-Benzyl-3,5-bis(2-fluorobenzylidene)piperidin-4-one
The inversion-related molecules of the title compound, C26H21F2NO, associate into closed dimeric subunits via co-operative C—H⋯π interactions. Two non-classical C—H⋯O and one C—H⋯N intramolecular hydrogen bonds are also found in the crystal structure. The piperidin-4-one ring adopts a sofa conforamtion with the 1-benzyl group in the equatorial position, and the equiplanar fluorophenyl substituents in the 3- and 5-positions stretched out on either side. The 1-benzyl group is disposed towards the substituent in the 6th position of the piperidin-4-one ring. The 3,5-diene units possess E configurations
Long-term contraceptive efficacy of vaccine of ovine follicle-stimulating hormone in male bonnet monkeys (Macaca radiata)
A group of ten healthy fertile adult male bonnet monkeys were actively immunized using
procedures acceptable for human use with pure follicle-stimulating hormone (oFSH) isolated from sheep
pituitaries. The vaccine elicited an immunogenic response in all ten monkeys; the antibody-binding
capacity, determined by Scatchard analysis, varied from 3 to 18 μg oFSH ml-1, the
binding affinity ranging from 0.13 to 2.0 × 1010mol-1. A substantial
population of antibodies against oFSH crossreacted with 125I-labelled human (h) FSH, used
here as a representative ligand of primate FSH. The bioneutralization activity of the antisera
assessed by a specific bioassay in vitro, when the antibody titre was high, was 6.9 ± 0.18
μg hFSH ml-1. Immunization for 4.7-5.7 years did not affect the health and libido of
the animals. Concentration of testosterone in serum remained normal throughout the study, but, within
150 days of immunization, there was a marked decrease (75-100%) in the number of spermatozoa in
seminal ejaculates. Oligospermic status interspersed with azoospermia was maintained by periodic
boosting. The fertility of these animals was monitored between 6 months and 2 years after primary
immunization. All the ten animals proved infertile in repeated mating experiments with females of
proven fertility. After stopping booster injections, nine of ten animals regained fertility, but the
time taken for this depended upon the rate of decline of antibody titres. Re-boosting these monkeys
with 100 μg oFSH after confirming that recovery had occurred revealed prompt increases in
antibody titres followed once again by onset of oligo-azoospermia and infertility, underscoring the
specificity of immunization effect. The immunized monkeys, apart from being acutely oligospermic,
ejaculated spermatozoa that were markedly deficient in key acrosomal enzymes, such as acrosin and
hyaluronidase, and motility as well as in their ability to penetrate a gel in vitro, suggesting that
the infertility observed was due to gross reductions in the numbers of spermatozoa that could
effectively interact with the oocyte and cause successful fertilization
Pore resistivity variation by Resistivity imaging technique in sedimentary part of main Gadilam river basin, Cuddalore District, Tamil Nadu, India
Electrical resistivity is the only property of physics which give information of subsurface moisture content in the formation, Hence geophysical electrical resistivity survey was carried out to investigate the nature of shallow subsurface formations and geological contact in the main Gadilam river basin of Cuddalore District in Tamil Nadu. Twenty-seven vertical electrical soundings (VES) were conducted by Schlumberger configuration in the basin. Data is interpreted by curve matching techniques using IPI2 WIN software, layer parameters like apparent resistivity (?a) and thickness (h) interpretation were exported to Geographic Information System (GIS). Interpretation distinguishes three major geoelectric layers like topsoil, sandy clay layer, clayey sand layer along the contact zone in the basin. Interpreted VES sounding curves are mostly four-layer cases of QH, H, HA and KH type. Investigation demarcates lithology of subsurface and hydrogeological set up by employing maximum possible electrode sounding to infer saline water and freshwater occurrence based on resistivity signals. Zone of groundwater potential map was prepared with the combination of resistivity (?= ?1+ ?2+ ?3+ ?4) and corresponding thickness (T= T1+T2+T3+T4). High resistivity value of >200 ? m and low resistivity value of <10 ? m show the occurrence of alkaline and saline water within the formation aquifers as a result of possible rock water interaction and saline water dissolution. Four-layer resistivity cases from the matched curve (namely KH, AH, QA, and KA type) show the resistivity distribution/variation. It separates the freshwater depth wish from 1 to 140 ? m in fluvial sediments. Flood basin, sandstone and clay layer with low resistivity value of 3.16 - 7.5 ? m indicates contact with saline and freshwater aquifer. The Iso – resistivity map delineates saline water and freshwater zones with in the fourth layer cases in the same locations to indicate the irrational way of abstracting groundwater, resulting in saltwater ingress
(3E,5E)-3,5-Bis(4-allyloxybenzylidene)-1-benzylpiperidin-4-one
In the title compound C32H31NO3, the allyloxy groups on either side of the piperidin-4-one ring are conformationally disordered. The contribution of major and minor components of the allyloxy group at the 3rd position of the ring are 0.576 (4) and 0.424 (4), respectively, and those at the 5th position are 0.885 (3) and 0.115 (3), respectively. The six-membered piperidin-4-one ring adopts a sofa conformation with the benzyl group occupying an equatorial position and the olefinic double bonds possessing an E configuration. Flanking phenyl substituents are stretched out on either side of the six-membered ring. π–π interactions with a centroid–centroid distance of 3.885 (1) Å give rise to molecular dimers and short C—H⋯π contacts lead to chains along the c axis
Recent Trends in the Production, Purification and Application of Lactic Acid
Lactic acid, a naturally occurring multifunctional organic acid, is a valuable industrial chemical used as an acidulant, preservative in the food industry, pharmaceutical, leather, and textile industries, as well as a chemical feedstock. One of the most promising applications of lactic acid is its use for biodegradable and biocompatible lactate polymers, such as polylactic acid. Lactic acid can be produced either by fermentation or by chemical synthesis but the biotechnological fermentation process has received significant importance due to environmental concerns, use of renewable resources instead of petrochemicals, low production temperature, low energy requirements and high purity. There are numerous investigations on the development of biotechnological methods for lactic production, with an ultimate objective to enable the process to be more efficient and economical. This review discusses the various recent fermentation technologies to produce lactic acid, different microorganisms involved in the production of lactic acid, purification and wide industrial applications of lactic acid
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