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1.
Priyanka Mishra Mahendra Pal Singh Negi Mukesh Srivastava Kiran Singh Singh Rajender 《Reproductive biology and endocrinology : RB&E》2018,16(1):103
Background
Since the first report of a decline in semen quality in 1974, there have been several reports of similar declines across populations. Despite some scattered reports of declining semen quality in the Indian sub-continent, comprehensive studies analyzing semen quality over the last few decades have not been undertaken. We undertook the present study to investigate the temporal trend in semen parameters in Indian populations over a period of 37 years (1979–2016).Methods
Publications providing semen analysis details for fertile and infertile men from the Indian sub-continent were collected by a thorough literature search. Semen quality data for 6466 normal fertile or presumptive normal men (from 119 studies/data sets) and 7020 infertile men (from 63 studies/data sets) published between 1979 and 2016 were retrieved. We undertook systematic review and quantitative analysis of mean sperm count, motility, normal morphology and other available parameters. Data were analyzed to estimate semen parameters reference values for Indian men and to assess temporal trends in infertile, fertile and all subjects.Results
Seminal quality shows a decreasing temporal trend and the decrease is higher in infertile than fertile males. In pooled analysis for all individuals, significant (p?<?0.05 or?<?0.001) declines in sperm concentration and normal morphology are observed; however, isolated analysis for each group shows declines without statistical significance. The mean (± SD) semen volume, sperm concentration, total motility, rapid linear progressive motility, normal sperm morphology and sperm viability for Indian fertile men are 2.88?±?0.77 ml, 81.08?±?29.21 million/ml, 66.37?±?10.95%, 52.64?±?15.78%, 56.68?±?20.23% and 72.63?±?8.31%, respectively, whereas in infertile these are 3.07?±?1.27 ml, 37.94?±?26.41 million/ml, 40.22?±?13.76%, 26.79?±?15.47%, 36.41?±?21.66% and 55.25?±?11.99%, respectively. The mean seminal parameter values were significantly lower (p?<?0.001) in infertile as compared to fertile men, except semen volume.Conclusions
Semen parameters in Indian men have declined with time and the deterioration is quantitatively higher in the infertile group. The study also provides reference values for semen parameters in Indian men.2.
Understanding the flow of ions through E. coli porin outer membrane protein F (OmpF) requires knowledge of the charge state of all titratable residues located along the
permeation pathway. Earlier theoretical studies proved successful in the calculation of the pK values of most residues. The
(apparent) pK of Asp37 (D37), on the other hand, appeared rather sensitive to the (unknown) protein dielectric used. We addressed
the protonation state of D37 experimentally by replacing D37 with a (neutral) valine. This D37V mutant expressed reduced cation
selectivity, in agreement with the view that D37 in wild-type (WT) OmpF is fully ionized, i.e., deprotonated. The introduction
of a (positively charged) arginine at position 37 evoked current fluctuations. Similar behavior was observed in the D37K mutant
and the cysteine mutants D37C-MTSEA and D37C-MTSET. Nontitratable [2-(trimethylammonium)ethyl]-methanethiosulfonate (MTSET)
carries a permanent and pH-independent charge of 1e, implying that the fluctuations of the D37C-MTSET mutant do not represent (de)protonation reactions of MTSET. We therefore
conclude that these fluctuations reflect transitions between conformational substates evoked by structural instabilities due
to the positive charge at that particular position in the pore lumen. Based on the similarities between D37C-MTSET fluctuations
and those seen in the other mutants, notably D37K, the underlying mechanism of these fluctuations may be (essentially) the
same in all four mutants studied. 相似文献
3.
Masanori Ogawa Takashi Takabatake Tadashi C. Takahashi K. Takeshima 《Development genes and evolution》1997,206(7):417-424
EP37 is an epidermis-specific protein found in the developing embryo of the Japanese newt, Cynops pyrrhogaster. Our previous study predicted the presence of genes homologous to EP37, which show temporary shared expression at the turn
of metamorphosis. In this study, we isolated and characterized three cDNAs encoding novel EP37 homologues; two from the skin
of an adult newt and the other from swimming larva. Conceptual translation of the open reading frames of these cDNAs predicted
proteins carrying βγ-crystallin motifs and putative calcium-binding sites, both of which are features shared by the originally
identified EP37 (EP37L1), as well as a spore coat protein of Myxococcus
xanthus, protein S. Immunoblot analyses and immunohistochemical studies indicated that two of the EP37 proteins, EP37L1 and EP37L2,
are exclusively expressed in the epidermis (skein cells) including the figures of Eberth at premetamorphic stages. During
and after metamorphosis, the expression of EP37 proteins was mainly observed in cutaneous glands, and a molecular transition
to the adult types of EP37, EP37A1 and EP37A2, occurred. These observations suggest that EP37 proteins play an important role
in construction of integumental tissues and adaptation to the aquatic or amphibious environment.
Received: 6 September 1996 / Accepted: 30 October 1996 相似文献
4.
《生物化学与生物物理学报:生物膜》1986,862(2):329-334
5.
To investigate the interaction between white spot syndrome virus (WSSV)-VP37 and gill membrane proteins (GMPs) of Pacific white shrimp (Litopenaeus vannamei), the VP37 protein was expressed and purified, and a distinct 53 kDa VP37-binding protein band was identified in GMPs by virus overlay protein binding assay and GST pull-down assay. By electroelution, the VP37 binding protein was purified and identified as F1ATP synthase β (F1ATPase β) subunit by Mass Spectrometry. The purified F1ATPase β subunit was used to immunize BALB/C mice to produce monoclonal antibodies (Mabs). After cell fusion, sixteen hybridomas secreting Mabs against F1ATPase β subunit of L. vannamei were screened by enzyme-linked immunosorbant assay (ELISA), three of which designated as 1D5, 1E8 and 2H4 were cloned by limiting dilution and further characterized by indirect immunofluorescence assay (IIFA) and western blotting. The results of IIFA showed that specific fluorescence signals located at the peripheral zone of the gills of L. vannamei. Western blotting demonstrated that three Mabs reacted specifically with the 53 kDa protein band in GMPs of L. vannamei. By IIFA, the Mabs could also cross-react with the gill cells of three other WSSV-susceptible shrimps Fenneropenaeus chinensis, Penaeus monodon and Marsupenaeus japonicus. Furthermore, the three anti-F1ATPase β subunit Mabs could partially block the binding of WSSV to GMPs by ELISA in vitro, and also exhibited direct anti-WSSV activity in shrimp by neutralization assay in vivo. These findings suggested that F1ATPase β subunit involved in WSSV infection in L. vannamei. 相似文献
6.
Guntur Fibriansah Thiam-Seng Ng Victor A. Kostyuchenko Jaime Lee Sumarlin Lee Jiaqi Wang Shee-Mei Lok 《Journal of virology》2013,87(13):7585-7592
Previous binding studies of antibodies that recognized a partially or fully hidden epitope suggest that insect cell-derived dengue virus undergoes structural changes at an elevated temperature. This was confirmed by our cryo-electron microscopy images of dengue virus incubated at 37°C, where viruses change their surface from smooth to rough. Here we present the cryo-electron microscopy structures of dengue virus at 37°C. Image analysis showed four classes of particles. The three-dimensional (3D) map of one of these classes, representing half of the imaged virus population, shows that the E protein shell has expanded and there is a hole at the 3-fold vertices. Fitting E protein structures into the map suggests that all of the interdimeric and some intradimeric E protein interactions are weakened. The accessibility of some previously found cryptic epitopes on this class of particles is discussed. 相似文献
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9.
Dutta RK Kathania M Raje M Majumdar S 《The international journal of biochemistry & cell biology》2012,44(6):942-954
The significance of IL-6 production in tuberculosis is yet to be fully elucidated, although it is known for quite some time that IL-6 interferes with IFN-γ induced signal. In order to know which cellular process induced by IFN-γ is actually counteracted by IL-6, we studied the role of IL-6 on IFN-γ induced autophagy formation in virulent Mycobacterium tuberculosis infection in THP-1 cells, since it is well characterized that induction of autophagy by IFN-γ eliminates intracellular mycobacterium by overcoming the phagosome maturation block imposed by bacilli. We report here that IL-6 inhibits both IFN-γ and starvation induced autophagy in M. tuberculosis H37Rv infected cells. M. tuberculosis H37Rv infection results in time dependent production of IL-6 in THP-1 cells and neutralization of this endogenous IL-6 by anti-IL-6 antibody significantly enhances the IFN-γ mediated killing of the intracellular bacteria. IL-6 time dependently lowers Atg12-Atg5 complex and therefore inhibits autophagosome biogenesis rather than autophagolysosome formation. IL-6 also affects IFN-γ mediated stimulation of mTOR, p-38 and JNK pathways. These results clearly indicate that virulent mycobacteria strategically upregulate IL-6 production to combat innate immunity. 相似文献
10.
Expression of connexin 37, 40 and 43 in rat mesenteric arterioles and resistance arteries 总被引:2,自引:2,他引:0
Gustafsson F Mikkelsen HB Arensbak B Thuneberg L Neve S Jensen LJ Holstein-Rathlou NH 《Histochemistry and cell biology》2003,119(2):139-148
Connexins are the protein constituents of gap junctions which mediate intercellular communication in most tissues. In arterioles gap junctions appear to be important for conduction of vasomotor responses along the vessel. Studies of the expression pattern of connexin isoforms in the microcirculation are sparse. We investigated the expression of the three major vascular connexins in mesenteric arterioles (diameter <50 micro m) from male Sprague-Dawley rats, since conducted vasomotor responses have been described in these vessels. The findings were compared with those obtained from upstream small resistance arteries. Indirect immunofluorescence techniques were used on whole mounts of mesenteric arterioles and on frozen sections of resistance arteries (diameter approximately 300 micro m). Mesenteric arterioles expressed Cx40 and Cx43 in the endothelial layer, and Cx37 was found in most but not all vessels. Connexins were not demonstrated in the media. In resistance arteries endothelial cells expressed Cx37, Cx40 and Cx43. Ultrastructural studies of mesenteric arterioles confirmed that gap junction plaques between endothelial cells are present, whereas myoendothelial, or smooth muscle cell gap junctions could not be demonstrated. The findings suggest that smooth muscle cells in mesenteric arterioles may not be well coupled and favour that conducted vasomotor responses in these vessels are propagated through the endothelial cell layer. 相似文献
15.
Preparations of radioactive lysosomes were obtained from mouse kidney after injection of radioactive iodine-labeled bovine ribonuclease. Stability of these lysosomes in various media was estimated from measurements of proteolytic activity towards the ribonuclease, and of ribonuclease retention in particles. The lysosomes were stable at 37 °C in isotonic, sucrose-free solutions of KCl, NaCl and potassium acetate, and in mixtures of these with MgCl2, showing that these salts are relatively impermeant through the lysosomal membranes. The membranes were less permeable to Na+ than to K+. Both KCl and NaCl exerted their optimal protective effects over a broad concentration range above 0.125 M in 0.025 M acetate buffer. Mg2+ enhanced the protective effect of both K+ and Na+; the osmotic effect of 0.075 M NaCl-0.05 M MgCl2 was indistinguishable during the entire course of ribonuclease digestion from that of isotonic sucrose. Osmotic protection by KCl-MgCl2 was demonstrated over the pH range 5.5–7.0. A marked alteration in membrane properties occurs at lower temperatures in 0.11 M KCl-0.01 M MgCl2 such that, at 0 °C, K+ permeability is much higher than at 37 °C, as shown by a several-fold decrease in stability at the lower temperature. 相似文献
16.
The rate of synthesis and degradation of phospholipids in Mycobacterium smegmatis ATCC 607, grown at 27° C and 37° C was studied by incorporation of 32P into phospholipids and chase of radioactivity of the pulse-labelled phospholipids. A relatively low rate of synthesis and
degradation of phospholipids in cells growth at 27° C was observed as compared to those grown at 37° C. Phosphatidylethanolamine
(PE) had the maximum turnover at 37° C. However, at 27° C, cardiolipin (CL) showed a turnover rate higher than PE. Phosphatidylinositol
mannosides (PIMs) were metabolically more active at 37° C than at 27° C. The differences in metabolic activity of the phospholipids
at the two temperatures have been discussed. 相似文献