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101.
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   
102.
The Brunei–Indonesia–Malaysia–Philippines East Asia Growth Area (BIMP-EAGA) is located within the Coral Triangle, known to have the world’s richest biodiversity in marine flora and fauna. This region lies within the 10° N and 10° S of the Equator where natural populations of both Kappaphycus and Eucheuma grow luxuriantly and abundantly. It is in this same region where commercial cultivation of Kappaphycus and Eucheuma began in the Philippines around the mid-1960s. Commercial farming of Kappaphycus (which was originally called Eucheuma) was successful in the Philippines from the early 1970s, after which the technology was transferred to Indonesia and Malaysia in the late 1970s. No seaweed cultivation has been reported in Brunei. At present, carrageenophytes are cultivated in sub-tropical to tropical countries circumferentially around the globe within the 10° N and S of the Equator. However, their combined production is still low as compared to Indonesia, the Philippines, and Malaysia. Notably, few improvements in farming techniques have been made since its first introduction. Some of the major improvements were the introduction of deep-water farming using hanging long lines, multiple rafts, and spider webs in the Philippines; the use of short and long ‘loops’, instead of plastic ‘tie-tie’ in Indonesia; and mechanization in harvesting and use of solar “greenhouse” drying in Malaysia. Commercial cultivation of tropical red seaweeds in the BIMP-EAGA region is dominated by Kappaphycus and Eucheuma (carrageenophytes) and Gracilaria (agarophytes) and the area became the major region for the production of carageenophytes and agarophytes globally. In particular, Indonesia is a major center for the production of Gracilaria. There is an increasing demand for other agarophytes/carrageenophytes in the international market such as Gelidium spp., Pterocladia spp., Porphyroglossum sp., and Ptilophora sp. for paper and ethanol production in Indonesia and Malaysia, and Halymenia for phycoerythrin pigments in the Philippines currently pursued in an experimental stage. A summary of the present status, problems, sustainability, and challenges for the cultivation of tropical red seaweeds in the BIMP-EAGA region are discussed in this paper.  相似文献   
103.
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   
104.
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   
105.
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   
106.
Kivrak  Hasan  Cakmak  Furkan  Kose  Hatice  Yavuz  Sirma 《Cluster computing》2022,25(3):1665-1675
Cluster Computing - Social navigation is beneficial for mobile robots in human inhabited areas. In this paper, we focus on smooth path tracking and handling disruptions during plan execution in...  相似文献   
107.
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   
108.
Abstract

Calcium carbonate (CaCO3) is found in different polymorph structures such as aragonite, vaterite, and calcite. The most common and stable form of CaCO3, calcite, which is abundant in sedimentary rocks as magnesite ore. Magnesite has application areas in many industrial fields including paper, pharmaceutical and refractory materials. Magnesite is theoretically formulated MgCO3, but contains many impurities (silicium, iron, and also calcite), that limits its usability and applicability. In this research, we aimed to investigate the decalcification possibility of the raw magnesite material through application of Enterococcus feacelis (EF) with CaCO3 dissolution ability. The exact mechanism of CaCO3 dissolution was investigated by carbonic anhydrase enzyme assay and HPLC analysis of organic acids produced by EF. Consequently, EF reduced the amount of CaCO3 from 2.94% to 0.49% which means a reduction (≈83.33%) in the rate of CaCO3 percentage. As a result of the experiments, it was observed that different organic acids produced by bacteria reacted with CaCO3 and removed the lime of magnesite ore. The bacteria used in the study did not show any pathogenic properties in rats, thus, it can be used safely for the industrial applications.  相似文献   
109.
110.
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   
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