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991.
Glycated albumin levels showed a progressive increase during normal pregnancy. The mean values (mole hexose/mole protein) were 1.68 +/- 0.27 (n = 15) in nonpregnant women, 1.83 +/- 0.21 (n = 11) in first trimester, 2.00 +/- 0.41 (n = 13) in second trimester, and 2.42 +/- 0.49 (n = 15) in third trimester. Glycated hemoglobin levels indicated a biphase pattern with low values at midpregnancy (controls 0.29 +/- 0.05, first trimester 0.30 +/- 0.04, second trimester 0.27 +/- 0.05, and third trimester 0.33 +/- 0.04). The data suggest that glycated albumin reflects the decreased glucose tolerance in pregnancy better that glycated hemoglobin levels. The reasons for the differing pattern of the two glycated proteins are discussed. 相似文献
992.
Kusum Sharma Lidija Timcenko-Youssef Sunil Palchaudhuri 《FEMS microbiology letters》1988,55(1):105-111
Abstract Outer membranes of Shigella species and E. coli K-12 carrying large invasive plasmids and isogenic non-invasive strains without plasmids were analyzed by SDS-PAGE. The immunoblotting analysis of the outer membrane proteins of these bacteria was performed with monoclonal antibody (mAb) made against A and B subunits of Shiga-like toxin (SLT). The SLT was detected in the outer membranes of S. dysenteriae 1 IDBM11, S. sonnei PNS20, S. flexneri M90T, S. dysenteriae 60R, and E. coli K-12 strain AB2463. The two other E. coli K-12 strains, C600 and 933J were included as controls for low and high toxin producers respectively. The outer membrane protein band of molecular weight 70 kDa was common to all bacterial strains studied. The most prominent band of 70 kDa protein was seen to be present in the high toxin producing plasmidless strain of S. dysenteriae 60R and the lysogenic strain of E. coli 933J. The invasive strains of S. dysenteriae 1 and S. flexneri M90T which carry the large invasive plasmids showed the least prominent band of 70 kDa protein.
The immunoblotting analysis of Shiga-toxin partially purified from the S. dysenteriae 60R strain revealed the absence of 70 kDa band on SDS-PAGE, instead the two dissociated subunits were seen. Furthermore, periplasmic Shiga-toxin proteins also showed the complete dissociation into A and B subunits. However, under the same denaturing conditions, the 70 kDa protein band cross-reacting with mAb against A and B subunits was still present in the outer membranes of all different strains. 相似文献
The immunoblotting analysis of Shiga-toxin partially purified from the S. dysenteriae 60R strain revealed the absence of 70 kDa band on SDS-PAGE, instead the two dissociated subunits were seen. Furthermore, periplasmic Shiga-toxin proteins also showed the complete dissociation into A and B subunits. However, under the same denaturing conditions, the 70 kDa protein band cross-reacting with mAb against A and B subunits was still present in the outer membranes of all different strains. 相似文献
993.
Cyclosporin A (CsA) was initially developed as an immunosuppressive drug. In the past several years, it has been shown to possess antiparasite activity independent of the immune system. It is not known how the drug exerts these antiparasite effects, or why it is stage and/or species specific. The answers may lie in the enzymatic function of cyclophilins. The cyclophilins are a growing family of proteins that exhibit peptidyl-prolyl cis-trans isomerase (PPiase) activity and bid CsA to varying degrees. PPiases have been shown to play a role in the folding of many essential proteins. Antony Page, Sanjay Kumar and Clotilde Carlow here review parasite cyclophilins and their association with CsA. The possible biological function of parasite cyclophilins and their potential role in future drug discovery are also discussed. 相似文献
994.
The postulates of developmental instability–sexual selection hypothesis is intensely debated among evolutionary biologists, wherein despite a large amount of empirical data, evidence for or against it has been largely inconclusive. A key assumption of this hypothesis is that animals assess symmetry in potential mates as an indicator of genetic quality (developmental stability), and consequently use this information to discriminate against those with higher asymmetries while choosing mates. However, the perceptional basis that must underlie such discriminatory behavior (is symmetry a signal or is symmetry signaled) is not clearly defined. It is also argued that since asymmetry levels in natural populations are very low, the low signal‐to‐noise ratio would make accurate assessment of symmetry both difficult and costly. Rather than attempting to validate this hypothesis or even as to whether animals assess mate symmetry, this review simply aims to examine the plausibility that animals perceive symmetry (directly or indirectly) and consequently discriminate against asymmetric mates in response to perceived irregularities during courtship. For this, we review mate choice and courtship literature to identify potential sensory cues that might advertise asymmetry or lead to discrimination of asymmetric individuals. Although signaling associated with mate choice is commonly multimodal, previous studies on asymmetry have mainly focused on visual perception. In the light of a recent study (Vijendravarma et al., 2022, Proceedings of the National Academy of Sciences of the United States of America, 119, e2116136119), this review attempts to balance this bias by emphasizing on non‐visual perception of asymmetry. In conclusion, we discuss the methodological challenges associated with testing the role of multimodal cues in detecting mate asymmetry, and highlight the importance of considering ecological, behavioral, and evolutionary aspects of animals while interpreting empirical data that test such hypothesis. 相似文献
995.
Saurabh Kumar Agnihotri Balawant Kumar Ankita Jain Anjali Anjali Mahendra Pal Singh Negi Rekha Sachan Madan Lal Brahma Bhatt Raj Kamal Tripathi Monika Sachdev 《Reports of Biochemistry & Molecular Biology》2022,10(4):711
Background:This study correlates the serum levels of sCD95 & TNF-α with a simple cell-based assay to evaluate the capacity of the serum sample to induce apoptosis in Jurkat cells. Interlinking of these parameters can be explored to design a minimum invasive diagnostic strategy for cervical cancer (CC).Methods:Sera samples were assessed to induce apoptosis in Jurkat cells through FACS. Serum levels of sCD95 and TNF-α were measured by ELISA. JNK phosphorylation was evaluated in sera incubated Jurkat cells. Data was scrutinized through statistical analysis.Results:Significantly higher serum levels of sCD95 and lower TNF-α levels were observed in CC patients; their sera samples inhibited induction of apoptosis in Jurkat cells through reduced JNK phosphorylation. Statistical analysis linked these three parameters for the early screening of CC.Conclusion:Distinct sera levels of sCD95 & TNF-α in CC patients showed an anti-apoptotic effect, which can be considered for early detection of CC.Key Words: Apoptosis, sCD95, Jurkat Cells, Tumor Necrosis Factor-alpha, Uterine Cervical Neoplasms 相似文献
996.
997.
Transmission bottlenecks introduce selection pressures on HIV-1 that vary with the mode of transmission. Recent studies on small cohorts have suggested that stronger selection pressures lead to fitter transmitted/founder (T/F) strains. Manifestations of this selection bias at the population level have remained elusive. Here, we analysed early CD4 cell count measurements reported from ∼340,000 infected heterosexual individuals (HET) and men-who-have-sex-with-men (MSM), across geographies, ethnicities and calendar years. The reduction in CD4 counts early in infection is reflective of the virulence of T/F strains. MSM and HET use predominant modes of transmission, namely, anal and penile-vaginal, with among the largest differences in the selection pressures at transmission across modes. Further, in most geographies, the groups show little inter-mixing, allowing for the differential selection bias to be sustained and amplified. We found that the early reduction in CD4 counts was consistently greater in HET than MSM (P<0.05). To account for inherent variations in baseline CD4 counts, we constructed a metric to quantify the extent of progression to AIDS as the ratio of the reduction in measured CD4 counts from baseline and the reduction associated with AIDS. We found that this progression corresponding to the early CD4 measurements was ∼68% for MSM and ∼87% for HET on average (P<10−4; Cohen’s d, ds = 0.36), reflecting the more severe disease caused by T/F strains in HET than MSM at the population level. Interestingly, the set-point viral load was not different between the groups (ds<0.12), suggesting that MSM were more tolerant and not more resistant to their T/F strains than HET. This difference remained when we controlled for confounding factors using multivariable regression. We concluded that the different selection pressures at transmission have resulted in more virulent T/F strains in HET than MSM. These findings have implications for our understanding of HIV-1 pathogenesis, evolution, and epidemiology. 相似文献
998.
999.
So far, oil‐rewarding flowers are known to be pollinated only by oil‐collecting bees, which gather and use lipids for larval feed and nest building. As honeybees do not have oil‐collecting appendages on their legs, they have not been associated with pollination of such flowers. In a predominantly Apis pollinated and food deceptive clade of wild Cymbidiums, we investigated the reproductive strategy of Cymbidium aloifolium, hitherto unknown for its floral oil reward. Our study demonstrates the requisites for establishment of mutualistic interaction between the oil flower and Apis cerana indica, a corbiculate bee. Success in pollination requires learning by honeybees to access the food reward, thereby displaying cognitive ability of the pollinator to access the customized reward. Morphometric matching between orchid flowers and the pollinator, and that between pollinia and stigmatic cavity also appear to be essential in the pollination success. Absence of pollinator competition and prolonged flower‐handling time are suggested to promote floral constancy. The present study highlights the need to explore the spectrum of pollination rewards pursued by honeybees, which may include unconventional composition of floral resources. 相似文献
1000.
Following acute sciatic nerve crush injury (SNCI), inflammation and the improper phagocytic clearance of dying Schwann cells (SCs) has effects on remodeling that lead to morbidity and incomplete functional recovery. Therapeutic strategies like the use of erythropoietin (EPO) for peripheral nerve trauma may serve to bring immune cell phagocytotic clearance under control to support debris clearance. We evaluated EPO’s effect on SNCI and found EPO treatment increased myelination and sciatic functional index (SFI) and bolstered anti-apoptosis and phagocytosis of myelin debris via CD206+ macrophages when compared to saline treatment. EPO enhanced M2 phenotype activity, both in bone marrow-derived macrophages (BMMØs) and peritoneal-derived macrophages (PMØs) in vitro, as well as in PMØs in vivo. EPO increased efferocytosis of apoptotic sciatic nerve derived Schwann cells (SNSCs) in both settings as demonstrated using immunofluorescence (IF) and flow cytometry. EPO treatment significantly attenuated pro-inflammatory genes (IL1β, iNOS, and CD68) and augmented anti-inflammatory genes (IL10 and CD163) and the cell-surface marker CD206. EPO also increased anti-apoptotic (Annexin V/7AAD) effects after lipopolysaccharide (LPS) induction in macrophages. Our data demonstrate EPO promotes the M2 phenotype macrophages to ameliorate apoptosis and efferocytosis of dying SCs and myelin debris and improves SN functional recovery following SNCI.Subject terms: Neurodegeneration, Somatic system 相似文献