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101.
Synthesis of novel piperidinyl linker based ET cassettes and terminators is described These novel terminators are evaluated in the DNA sequencing experiments using thermostable DNA polymerase.  相似文献   
102.
Genetic affinities of 21 tribal populations of Andhra Pradesh are reported in terms of genetic distance analysis with regard to AB0 and Rh loci. These tribal populations show a high degree of differentiation in the distribution of AB0 blood groups. Some tribes exhibit the monomorphism for Rh (D) locus. The genetic distance analysis reveals that the 21 tribes included in this study are genetically distant from one another and the genetic clustering pattern correlates with linguistic/ethnic affiliation and geographical propinquity of these tribal populations to a certain extent. The possible reasons for different cluster formations are discussed.  相似文献   
103.

Background

Road trauma is a leading cause of death and injury in young people. Traffic offences are common, but their importance as a risk indicator for subsequent road trauma is unknown. This cohort study assessed whether severe road trauma could be predicted by a history of prior traffic offences.

Methodology and Principal Findings

Clinical data of all adult road trauma patients admitted to the Western Australia (WA) State Trauma Centre between 1998 and 2013 were linked to traffic offences records at the WA Department of Transport. The primary outcomes were alcohol exposure prior to road trauma, severe trauma (defined by Injury Severity Score >15), and intensive care admission (ICU) or death, analyzed by logistic regression. Traffic offences directly leading to the road trauma admissions were excluded. Of the 10,330 patients included (median age 34 years-old, 78% male), 1955 (18.9%) had alcohol-exposure before road trauma, 2415 (23.4%) had severe trauma, 1360 (13.2%) required ICU admission, and 267 (2.6%) died. Prior traffic offences were recorded in 6269 (60.7%) patients. The number of prior traffic offences was significantly associated with alcohol-related road trauma (odds ratio [OR] per offence 1.03, 95% confidence interval [CI] 1.02–1.05), severe trauma (OR 1.13, 95%CI 1.14–1.15), and ICU admission or death (OR 1.10, 95%CI 1.08–1.11). Drink-drinking, seat-belt, and use of handheld electronic device offences were specific offences strongly associated with road trauma leading to ICU admission or death—all in a ‘dose-related’ fashion. For those who recovered from road trauma after an ICU admission, there was a significant reduction in subsequent traffic offences (mean difference 1.8, 95%CI 1.5 to 2.0) and demerit points (mean difference 7.0, 95%CI 6.5 to 7.6) compared to before the trauma event.

Significance

Previous traffic offences were a significant risk factor for alcohol-related road trauma and severe road trauma leading to ICU admission or death.  相似文献   
104.
The majority of studies pertaining to lead retention by clays and soils have examined the mechanisms, kinetics, and adsorption isotherms using the batch experiment technique that employs solid: water extracts of 1:10 and 1:20. Field soil deposits generally have much lower gravimetric water content ranging between 9 and 45%. Given the wide disparity in the solids: water ratio employed in the batch experiment technique and that prevailing in field deposits, this paper examines the lead retention characteristics of soils at field moisture contents (6%, 13%, and 25%) using artificially lead-contaminated soil specimens. A residually derived (i.e., formed by in-situ weathering of parent rock) red soil was used to prepare the artificially contaminated soil specimens. The impact of variations in clay content on lead retention was examined by diluting the residual soil with various amounts (0 to 60%) of river sand. Soil specimens remolded at 6 and 13% moisture contents produced very stiff to hard soils on compaction, while specimens remolded at 25% moisture content existed in the slurry state. The soil specimens were contaminated with low (30 mg/kg) to high (2500 mg/kg) concentrations of lead ions by remolding them with 160 ppm to 10,000 ppm ionic lead solutions. Lead retention by soils at field moisture contents was determined by extracting the lead from the soil using a water leach test. Experimental results showed that the bulk (71 to 99%) of the added lead was retained by the soil in insoluble form at the field moisture content. Correlations between the amount of lead retained and soil/solution parameters indicated that the amounts of Pb retained at field moisture content is a function of the initial Pb addition, total sand content, effective clay porosity, and soil pH.  相似文献   
105.

Global biodiversity monitoring systems through remote sensing can support consistent assessment, monitoring, modelling and reporting on biodiversity which are key activities intended for sustainable management. This work presents an overview of biodiversity monitoring components, i.e. biodiversity levels, essential biodiversity variables, biodiversity indicators, scale, biodiversity inventory, biodiversity models, habitat, ecosystem services, vegetation health and biogeochemical heterogeneity and discusses what remote sensing through Earth Observations has contributed to the study of biodiversity. The technological advancements in remote sensing have enabled information-rich data on biodiversity. Remote sensing data are making a strong contribution in providing unique information relevant to various biodiversity research and conservation applications. The extensive use of Earth observation data are not yet realized in biodiversity assessment, monitoring and conservation. The development of direct remote sensing approaches and the techniques for quantifying biodiversity at the community to species level is likely to be a great challenge for comprehensive earth observation-based monitoring strategy.

  相似文献   
106.
The IFN-inducible IFI16 and AIM2 proteins act as innate immune sensors for cytosolic double-stranded DNA (dsDNA). On sensing dsDNA, the IFI16 protein induces the expression of IFN-β whereas the AIM2 protein forms an inflammasome, which promotes the secretion of IL-1β. Given that the knockdown of IFI16 expression in human diploid fibroblasts (HDF) delays the onset of cellular senescence, we investigated the potential roles for the IFI16 and AIM2 proteins in cellular senescence. We found that increased IFI16 protein levels in old (vs. young) HDFs were associated with the induction of IFN-β. In contrast, increased levels of the AIM2 protein in the senescent (vs. old) HDFs were associated with increased production of IL-1β. The knockdown of type I IFN-α receptor subunit, which reduced the basal levels of the IFI16 but not of the AIM2, protein delayed the onset of cellular senescence. Accordingly, increased constitutive levels of IFI16 and AIM2 proteins in ataxia telangiectasia mutated (ATM) HDFs were associated with the activation of the IFN signaling and increased levels of IL-1β. The IFN-β treatment of the young HDFs, which induced the expression of IFI16 and AIM2 proteins, activated a DNA damage response and also increased basal levels of IL-1β. Interestingly, the knockdown of AIM2 expression in HDFs increased the basal levels of IFI16 protein and activated the IFN signaling. In contrast, the knockdown of the IFI16 expression in HDFs decreased the basal and dsDNA-induced activation of the IFN signaling. Collectively, our observations show differential roles for the IFI16 and AIM2 proteins in cellular senescence and associated secretory phenotype.  相似文献   
107.
Plant tissue culture and molecular biology techniques are powerful tools of biotechnology that can complement conventional breeding, expedite crop improvement and meet the demand for availability of uniform clones in large numbers. Jatropha curcas Linn., a non-edible, eco-friendly, non-toxic, biodegradable fuel-producing plant has attracted worldwide attention as an alternate sustainable energy source for the future. This review presents a consolidated account of biotechnological interventions made in J. curcas over the decades and focuses on contemporary information and trends of future research.  相似文献   
108.

Background

Type 1 Diabetes Mellitus is caused by auto immune destruction of insulin producing beta cells in the pancreas. Currently available treatments include transplantation of isolated islets from donor pancreas to the patient. However, this method is limited by inadequate means of immuno-suppression to prevent islet rejection and importantly, limited supply of islets for transplantation. Autologous adult stem cells are now considered for cell replacement therapy in diabetes as it has the potential to generate neo-islets which are genetically part of the treated individual. Adopting methods of islet encapsulation in immuno-isolatory devices would eliminate the need for immuno-suppressants.

Methodology/Principal Findings

In the present study we explore the potential of human adipose tissue derived adult stem cells (h-ASCs) to differentiate into functional islet like cell aggregates (ICAs). Our stage specific differentiation protocol permit the conversion of mesodermic h-ASCs to definitive endoderm (Hnf3β, TCF2 and Sox17) and to PDX1, Ngn3, NeuroD, Pax4 positive pancreatic endoderm which further matures in vitro to secrete insulin. These ICAs are shown to produce human C-peptide in a glucose dependent manner exhibiting in-vitro functionality. Transplantation of mature ICAs, packed in immuno-isolatory biocompatible capsules to STZ induced diabetic mice restored near normoglycemia within 3–4 weeks. The detection of human C-peptide, 1155±165 pM in blood serum of experimental mice demonstrate the efficacy of our differentiation approach.

Conclusions

h-ASC is an ideal population of personal stem cells for cell replacement therapy, given that they are abundant, easily available and autologous in origin. Our findings present evidence that h-ASCs could be induced to differentiate into physiologically competent functional islet like cell aggregates, which may provide as a source of alternative islets for cell replacement therapy in type 1 diabetes.  相似文献   
109.

Background

Antibodies to the water channel protein aquaporin-4 (AQP4), which is expressed in astrocytic endfeet at the blood brain barrier, have been identified in the serum of Neuromyelitis optica (NMO) patients and are believed to induce damage to astrocytes. However, AQP4 specific T helper cell responses that are required for the generation of anti-AQP4 antibodies and most likely also for the formation of intraparenchymal CNS lesions have not been characterized.

Methodology/Principal Findings

Using overlapping 15-meric peptides of AQP4, we identified the immunogenic T cell epitopes of AQP4 that are restricted to murine major histocompatibility complex (MHC) I-Ab. The N-terminal region of AQP4 was highly immunogenic. More precisely, the intracellular epitope AQP422–36 was detected as major immunogenic determinant. AQP482–108 (located in the second transmembrane domain), AQP4139–153 (located in the second extracellular loop), AQP4211–225 (located in the fifth transmembrane domain), AQP4235–249 (located in the sixth transmembrane domain), as well as AQP4289–306 in the intracellular C-terminal region were also immunogenic epitopes. AQP422–36 and AQP4289–303 specific T cells were present in the natural T cell repertoire of wild type C57BL/6 mice and T cell lines were raised. However, active immunization with these AQP4 peptides did not induce signs of spinal cord disease. Rather, sensitization with AQP4 peptides resulted in production of IFN-γ, but also IL-5 and IL-10 by antigen-specific T cells. Consistent with this cytokine profile, the AQP4 specific antibody response upon immunization with full length AQP4 included IgG1 and IgG2, which are associated with a mixed Th2/Th1 T cell response.

Conclusions and Significance

AQP4 is able to induce an autoreactive T cell response. The identification of I-Ab restricted AQP4 specific T cell epitopes will allow us to investigate how AQP4 specific autoimmune reactions are regulated and to establish faithful mouse models of NMO that include both cellular and humoral responses against AQP4.  相似文献   
110.
A comparative evaluation of As accumulation and subsequent effects upon exposure to arsenite [As(III)] was performed in three species of Ocimum. Plants accumulated high amount of As (μg g?1 dry weight; dw) (662 in O. tenuiflorum, 764 in O. basilicum and 831 in O. gratissimum at 100 μM As(III) after 10 days) with the order of accumulation being roots > stem > leaves. A significant reduction in plant height and biomass was observed. However, essential oil yield and major oil constituents, such as eugenol, methyl chevicol, and linalool, increased at lower As(III) concentrations [mostly up to 25 μM As(III)] in all three species. Positively, no detectable amount of As was found in oil of any species. The study proposes that Ocimum may be used as a phytoremediator and at the same time as a source of essential oils under proper regulation.  相似文献   
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