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91.
92.
This article puts forward the hypothesis that the Low Density Lipid Receptor (LDLR) is one of the molecules that is involved in the clearance of amyloid proteins in the brain and that it may play a role in Alzheimer’s Disease (AD) via its up-regulation by statins. The hypothesis is built on the following observations: a-statins (which have been shown to increase LDLR in astrocytes, see below) have a beneficial role in AD, b-defects in the LDL receptor gene are found in AD, c-molecules with similar structure to the LDLR have been shown to clear amyloid protein from the brain.  相似文献   
93.
The Muslims of Aligarh city are predominantly Sunnis, although there are also a considerable number of Shias. Among the Sunnis, approximately a quarter belong to Syed, Sheikh, Moghal and Pathan groups, and three-quarters belong to various lower biradaris. In the present study, 304 women attending the Primary Health Centre of the J. N. Medical College and Hospital, Aligarh Muslim University, Uttar Pradesh, were surveyed and the following recorded among Muslim women of high-rank (Ashraf) and low-rank (Ajlaf) castes: incidence of marriage, age of the mother at the time of marriage, present age of the mother, abortions, still births, pre-reproductive mortality and overall mortality. The Ashraf are comprised of the Sheikh, Syed and Pathan, whereas the Ajlafs have Qureshi, Saifi and Ansari biradaris. Maternal age was scored as above and below 45 years in each biradari. Significant effects of maternal age were seen on mortality of offspring, whereas populations did not show consistent differences, except when Ashrafs and Ajlafs were considered separately. The results show higher mortality and abortions for various groups. This may be due to various biological and socio-cultural factors, including hidden inbreeding in the remote past.  相似文献   
94.
BackgroundThe rapid and extensive spread of the COVID-19 pandemic has become a major cause of concern for both general public and healthcare profession.ObjectiveThe aim of this study is to analyze and evaluate the awareness of both the general public and healthcare providers in Qassim region in Saudi Arabia.MethodA cross-sectional study was conducted randomly in different shopping malls in Qassim region from 10th of February to 10th of March 2020. All participants have answered the designed questionnaire. The structured questionnaire recorded demographics and awareness of both public participants as well as health care providers.ResultA total of 130 participants have answered the designed questionnaire, out of which 67participants were males (58.5%) and 54 were females (41.5%). Overall, 129 (99%) out of the 130 participants are aware of COVID-19, and 116 (90%) have recognize it as a respiratory disease and 100% of the participants have recognized it as a contagious disease. Around 94% of the participants were able to recognize the correct incubation period of the virus. Participants of the age group 20–40 showed higher awareness level than other age groups (P value = 0.005). In addition, government employees showed higher awareness level than other profession groups (P = 0.039). Results showed significant positive correlation between the recognition of high-risk groups, reliable source of information, infection symptoms, disease prevention and available treatments.ConclusionGeneral public and health care professionals from Qassim Region showed adequate awareness of COVID-19. However, there is a strong need to implement periodic educational interventions and training programs on infection control practices for COVID-19 across all healthcare professions.  相似文献   
95.
Aptamers are short, single-stranded nucleic acids that fold into well-defined 3D structures which bind to a single target molecule (from small molecules to cells) with affinities and specificities that can rival those of antibodies (Jeong et al., 2009). Unlike antibodies, aptamers can be chemically synthesized eliminating the need for animals or cell culture, which also allows for selection under non-physiological conditions and broadens potential targets to include toxic molecules (Banka & Stockley, 2006). The compatibility of aptamers with nanomaterials, in combination with their affinity, selectivity, and conformational changes upon target interaction, have allowed for the development of a large number of therapeutic and targeted delivery systems in recent years exploiting these properties. Despite this, many challenges still exist as unprotected DNA is readily degraded by nucleases prevalent in biological and environmental systems (Bouchard et al., 2010). Embedding aptamers within multilayer polyelectrolyte films could provide a biodegradable shelter, while allowing the detection of diffusible small molecules. An understanding of these materials will allow for the eventual encapsulation of relevant payloads into aptamer–polyelectrolyte microcapsules towards the development of a controlled release system. In this work, films composed of natural polyelectrolytes chitosan and hyaluronan are employed due to their biocompatibility, strong presence in current literature, and amiability to layer-by-layer film construction. Initial progress towards the development of an aptamer-embedded polyelectrolyte film system will be presented.  相似文献   
96.
Bacterial communities and chitinase gene diversity of vermicompost (VC) were investigated to clarify the influence of earthworms on the inhibition of plant pathogenic fungi in VC. The spore germination of Fusarium moniliforme was reduced in VC aqueous extracts prepared from paper sludge and dairy sludge (fresh sludge, FS). The bacterial communities were examined by culture-dependent and -independent analyses. Unique clones selected from 16S rRNA libraries of FS and VC on the basis of restriction fragment length polymorphism (RFLP) fell into the major lineages of the domain bacteria Proteobacteria, Bacteroidetes, Verrucomicrobia, Actinobacteria and Firmicutes. Among culture isolates, Actinobacteria dominated in VC, while almost equal numbers of Actinobacteria and Proteobacteria were present in FS. Analysis of chitinolytic isolates and chitinase gene diversity revealed that chitinolytic bacterial communities were enriched in VC. Populations of bacteria that inhibited plant fungal pathogens were higher in VC than in FS and particularly chitinolytic isolates were most active against the target fungi.  相似文献   
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98.
Ethinylestradiol, a steroidal estrogen, is widely used with various progestogens in oral contraceptives formulations. There are sufficient evidences for the carcinogenicity of ethinylestradiol in experimental animals. The reports on the genotoxic potential of ethinylestradiol are contradictory. Here in the present study we have tested the genotoxicity of ethinylestradiol in human lymphocytes using chromosomal aberrations (CAs), mitotic index (MI) and sister chromatid exchanges (SCEs) as a parameter. The study was carried out in the absence, as well as in the presence, of rat liver microsomal fraction, with and without NADP. Ethinylestradiol was studied at three different concentrations (1, 5 and 10 microM) and was found non-genotoxic in the absence of metabolic activation (S9 mix) and in S9 mix without NADP. Ethinylestradiol was found to be genotoxic at 5 and 10 microM in the presence of S9 mix with NADP. To study the possible mechanism of the genotoxicity of ethinylestradiol, superoxide dismutase (SOD) and catalase (CAT) were used separately and in combination along with 10 microM of ethinylestradiol at different doses. SOD treatment increased CAs and SCEs and decreases MI as compared with treatment with 10 microM of ethinylestradiol alone in the presence of S9 mix with NADP at both of the tested doses. CAT treatment decreased the frequencies of CAs and SCEs and increased MI, as compared with treatment with 10 microM of ethinylestradiol alone in the presence of S9 mix with NADP. CAT treatment in combination with SOD also decreased the frequencies of CAs and SCEs and increased MI suggesting a possible role of reactive oxygen species for the genotoxic damage.  相似文献   
99.
BackgroundTinospora cordifolia (Thunb.) Miers (Giloy) has been applied successfully as an anti-inflammatory, anti-diabetic, and even as an anti-cancer agent. Yet, to date, the application of Giloy has not been explored concerning oral cancer.ObjectivesTo assess the effect of T cordifolia (Thunb.) Miers (Giloy) extract (TcE) on an oral cancer cell line.MethodsAW13516 (oral cancer cell line) cells were treated with the prepared aqueous extract of TcE for 24 h at various concentrations ranging between 5 μg/ml and 100 μg/ml and compared with control (cells without treatment). Thee effect of the extracts on apoptosis was assessed by through Annexin V flow cytometry assay and Luminometry based assessment of Caspase 8, 9 and caspase 3/7 activity. RNA was isolated from treated cells and gene expression of selected metastatic genes (MMP1, MMP10, and CXCL8); epithelial-mesenchymal stem cell genes (TWIST1, SNAIL, ZEB1, Oct4) and stemness related genses (Nanog, Sox2) were analyzed by using a quantitative real-time PCR system. The experiments were performed in triplicates.ResultsAqueous extract of TcE was found to induce apoptosis inducer in AW13516 cells in a concentration-dependent manner and was potent even at a low concentration of 5 μg/ml. The apoptosis induction was confirmed with the caspase activity assay. Treatment of the cells with the extract for 24 h exhibited a significant decrease in the expression of EMT genes in a dose-dependent manner without an effect on the metastatic genes.ConclusionAqueous extract of TcE induces apoptosis-mediated cell death in the oral cancer cell line AW13516 while attenuating its potential for epithelial mesenchymal transition.  相似文献   
100.
This study aimed to evaluate and compare the quality of κ‐carrageenan obtained from tissue‐cultured and field‐cultured Kappaphycus alvarezii. Carrageenan properties including yield, viscosity, gel strength and sulfate content were studied. After 60 days of cultivation, tissue‐cultured K. alvarezii showed a higher growth rate (6.3 ± 0.01% day?1) than field‐cultured seedlings (3.4 ± 0.3% day?1). The obtained carrageenan yield from tissue‐cultured (67.3 ± 16.4%) was higher than field‐cultured K. alvarezii (51.5 ± 21.0%). Gel viscosity of carrageenans from tissue‐cultured K. alvarezii (1280.0 ± 25.0 cP) was found significantly higher than field‐cultured samples (87.8 ± 20.9 cP). The 1.5% gel solution of tissue‐cultured and field‐cultured K. alvarezii exhibited gel strengths of 703.5 ± 14.1 and 288.3 ± 19.3 g cm?2, respectively. The average sulfate content of carrageenans was found to be significantly different between tissue‐cultured and field‐cultured K. alvarezii with 34.2 ± 10.9 and 7.5 ± 6.7%, respectively. Tissue culture is recommended to produce high quality seedlings by providing optimized culture conditions to the seaweed. This approach can serve as an alternative way to solve the seedling shortage problems currently faced by the seaweed industry.  相似文献   
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