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991.
992.
The occurrence and distribution of glycogen was investigated in cervical cells exfoliated under different physiologic and pathologic conditions using cytochemical parameters. The conditions studied included the menstrual cycle, menopause, the reproductive cycle and neoplastic lesions of the cervix in both premenopausal and postmenopausal and postmenopausal situations. The results obtained on the localization of this carbohydrate substance offer interesting information with respect to the absence and presence of glycogen in various degrees in different cell types. The presence of glycogen seems to be linked with cellular maturation; it disappears with the loss of differentiation during neoplasia. The high glycogen content during the menstrual cycle and reproductive cycle and its absence in postmenopause indicates a specific hormonal influence. The discrepancies noted in glycogen distribution in the same or different exfoliated cells obtained from different biologic states assume significance in light of various factors governing the synthesis and utilization of this polymer. 相似文献
993.
Jasmin Mecinović Christoph Loenarz Rasheduzzaman Chowdhury Christopher J. Schofield 《Bioorganic & medicinal chemistry letters》2009,19(21):6192-6195
Analogues of the 2-oxoglutarate cosubstrate of the human oxygen sensing enzyme prolyl hydroxylase domain 2 (PHD2) with variations in the potential iron-chelating group were screened as inhibitors and for binding (using non-denaturing electrospray ionization mass spectrometry) to PHD2. 相似文献
994.
The structure of lantanilic acid, a new triterpene isolated from the leaves of Lantana camara, has been determined as the β,β-dimethylacryloyl ester of lantaninilic acid. 相似文献
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996.
M. Trent Herdman Richard James Maude Md. Safiqul Chowdhury Hugh W. F. Kingston Atthanee Jeeyapant Rasheda Samad Rezaul Karim Arjen M. Dondorp Md. Amir Hossain 《PloS one》2016,11(4)
Delays in seeking appropriate healthcare can increase the case fatality of acute febrile illnesses, and circuitous routes of care-seeking can have a catastrophic financial impact upon patients in low-income settings. To investigate the relationship between poverty and pre-hospital delays for patients with acute febrile illnesses, we recruited a cross-sectional, convenience sample of 527 acutely ill adults and children aged over 6 months, with a documented fever ≥38.0°C and symptoms of up to 14 days’ duration, presenting to a tertiary referral hospital in Chittagong, Bangladesh, over the course of one year from September 2011 to September 2012. Participants were classified according to the socioeconomic status of their households, defined by the Oxford Poverty and Human Development Initiative’s multidimensional poverty index (MPI). 51% of participants were classified as multidimensionally poor (MPI>0.33). Median time from onset of any symptoms to arrival at hospital was 22 hours longer for MPI poor adults compared to non-poor adults (123 vs. 101 hours) rising to a difference of 26 hours with adjustment in a multivariate regression model (95% confidence interval 7 to 46 hours; P = 0.009). There was no difference in delays for children from poor and non-poor households (97 vs. 119 hours; P = 0.394). Case fatality was 5.9% vs. 0.8% in poor and non-poor individuals respectively (P = 0.001)—5.1% vs. 0.0% for poor and non-poor adults (P = 0.010) and 6.4% vs. 1.8% for poor and non-poor children (P = 0.083). Deaths were attributed to central nervous system infection (11), malaria (3), urinary tract infection (2), gastrointestinal infection (1) and undifferentiated sepsis (1). Both poor and non-poor households relied predominantly upon the (often informal) private sector for medical advice before reaching the referral hospital, but MPI poor participants were less likely to have consulted a qualified doctor. Poor participants were more likely to attribute delays in decision-making and travel to a lack of money (P<0.001), and more likely to face catastrophic expenditure of more than 25% of monthly household income (P<0.001). We conclude that multidimensional poverty is associated with greater pre-hospital delays and expenditure in this setting. Closer links between health and development agendas could address these consequences of poverty and streamline access to adequate healthcare. 相似文献
997.
Xiaodong Xiao Yan Chen Sheila Mugabe Changshou Gao Christine Tkaczyk Yariv Mazor Peter Pavlik Herren Wu William Dall’Acqua Partha Sarathi Chowdhury 《PloS one》2015,10(10)
High throughput screenings of single chain Fv (scFv) antibody phage display libraries are currently done as soluble scFvs produced in E.coli. Due to endotoxin contaminations from bacterial cells these preparations cannot be reliably used in mammalian cell based assays. The monovalent nature and lack of Fc in soluble scFvs prevent functional assays that are dependent on target cross linking and/or Fc functions. A convenient approach is to convert scFvs into scFv.Fc fusion proteins and express them in mammalian cell lines for screening. This approach is low throughput and is only taken after primary screening of monovalent scFvs that are expressed in bacteria. There is no platform at present that combines the benefits of both bacterial and mammalian expression system for screening phage library output. We have, therefore, developed a novel dual expression vector, called pSplice, which can be used to express scFv.Fc fusion proteins both in E.coli and mammalian cell lines. The hallmark of the vector is an engineered intron which houses the bacterial promoter and signal peptide for expression and secretion of scFv.Fc in E.coli. When the vector is transfected into a mammalian cell line, the intron is efficiently spliced out resulting in a functional operon for expression and secretion of the scFv.Fc fusion protein into the culture medium. By applying basic knowledge of mammalian introns and splisosome, we designed this vector to enable screening of phage libraries in a product like format. Like IgG, the scFv.Fc fusion protein is bi-valent for the antigen and possesses Fc effector functions. Expression in E.coli maintains the speed of the bacterial expression platform and is used to triage clones based on binding and other assays that are not sensitive to endotoxin. Triaged clones are then expressed in a mammalian cell line without the need for any additional cloning steps. Conditioned media from the mammalian cell line containing the fusion proteins are then used for different types of cell based assays. Thus this system retains the speed of the current screening system for phage libraries and adds additional functionality to it. 相似文献
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1000.
Sundarbans Biosphere Reserve (SBR) is the world's largest contiguous conserved mangrove forest with unique flora and fauna, but it still has to bear the brunt of anthropogenic disturbances due to huge population pressure. This study aimed to identify the sources, extent of metal pollution (Cd, Cr, Mn, Ni, Pb, and Zn), and their potential ecological risk in this fragile ecosystem. Sediments were collected from 10 locations with varied levels of anthropogenic pressure from the fringe of the reserve forest. Cluster analysis (CA) and factor analysis (FA) identified Ni, Cd, and Pb as the major anthropogenic pollutants in this area. Concentrations of Pb (27.79–47.07 mg/kg) and Cd (0.8–3.3 mg/kg) were found to be higher in areas reliant on fossil fuel-operated motorboats for transport and dependent on rechargeable batteries to cope with the shortage of electricity. The contamination factor (Cf), geoaccumulation index (Igeo), and ecological risk index (ERI) highlight that populated areas are mostly exposed to Cd, Pb, and Cr contamination. Interpolation maps identified that the central part of the area is acutely affected by Cd pollution, whereas the main ecotourism routes within the reserve forest have high Pb concentrations. This study concludes that conservation-friendly ecotourism and improper disposal of batteries can also pose a threat to this ecosystem and these possibilities could be considered during formulation of conservation plans. 相似文献