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271.
Shahriar?Dabiri Ashraf?KariminikEmail author Derek?Kennedy 《European cytokine network》2016,27(2):34-40
Chemokines and their corresponding receptors serve as pro-inflammatory and migratory signals for immune cells. CXCR3 and its corresponding ligands, CXCL9, CXCL10 and CXCL11, participate in the induction of immune responses against several foreign antigens. Numerous cells, including macrophages, NK cells and T lymphocytes, express CXCR3 and thus, expression of the receptor and its ligands can induce activity of these important immune cells against foreign antigens, including allogeneic grafts. Several parameters of the immune system participate in the induction and stimulation of powerful immune responses against allogeneic grafts. A thorough understanding of the parameters that regulate these responses can provide insights into new methods for immunotherapy during organ transplantation. The aim of this review is to address the most recent information regarding the roles played by CXCR3 and its corresponding ligands in the outcome of renal transplantation. 相似文献
272.
Yusra El Obaid Aisha Al Hamiz Abdishakur Abdulle Richard B. Hayes Scott Sherman Raghib Ali 《PloS one》2016,11(3)
Background
In developing medical research, particularly in regions where medical research is largely unfamiliar, it is important to understand public perceptions and attitudes towards medical research. In preparation for starting the first cohort study in the United Arab Emirates, the Abu Dhabi Cohort Study (ADCS), we sought to understand how we could improve the quality of the research process for participants and increase public trust and awareness of research.Methods
We conducted six focus groups (FG), consisting of Emirati men and women aged above 18 years to resemble the target population for the ADCS. Sampling was purposive and convenient. Data collection was an iterative process until saturation was reached with no new themes identified. Text from each FG was analyzed separately by identifying emerging issues and organizing related concepts into categories or themes. A coding tree was developed, consisting of the main concepts, themes, subthemes and corresponding quotes. Both themes and main ideas were identified using inductive analysis.Results
Forty-two participants enrolled at 3 academic centers (New York University Abu Dhabi, UAE University, Zayed University) and the Abu Dhabi blood bank. Focus group participants described lack of awareness of research as a challenge to participation in clinical research studies. Altruism, personal relevance of the research, and the use of role models were commonly identified motivators. Participants were generally satisfied with the informed consent process for the ADCS, but would be disappointed if not provided test results or study outcomes. Fear of a breach in confidentiality was a frequently expressed concern.Conclusions
Participants join research studies for varied, complex reasons, notably altruism and personal relevance. Based on these insights, we propose specific actions to enhance participant recruitment, retention and satisfaction in the ADCS. We identified opportunities to improve the research experience through improved study materials and communication to participants and the broader community. 相似文献273.
274.
The effects of increased salinity [NaCl + CaCl2] on seedlings of five accessions of pearl millet grown for 2 and 7 weeks, respectively, in salinised solution cultures at
EC 0.6, 4, 8, 12, 16, and 20 ds m−1 and sand cultures at EC 0.6 and 20 were assessed. There were no consistent relationships between seedlings characters at
two and seven weeks in response to increased salinity, and no single character provided an acceptable means of differentiating
cultivar/line response. The line having lower shoot mortality had a high root weight, a shoot:root ratio approaching 1, the
greatest shoot water content, and the greatest plant height. No relationship was found between these whole-plant characters
which suggest greater salinity tolerance, and the pattern of ion distribution, particularly Na+ and Cl−. Sufficient inter-cultivar/line variation in response to salinity was found to suggest that selection of individuals with
increased salinity tolerance is possible within pearl millet. 相似文献
275.
Frankia strains have been isolated from actinorhizal nodules of Alnus (2 strains), Casuarina (5 strains), Coriaria (1 strain), Datisca (3 strains), Elaeagnus (1 strain) and Hippophae (1 strain). The isolates were characterized for their growth on various carbon and nitrogen sources, nitrogen-fining ability in culture and nodulation of seedlings of the original host plant. 相似文献
276.
Summary The spermatozoon of Amblyomma hebraeum is about 200 m long and comprises: (1) a thick, club-shaped anterior part, about 20 m long bearing at its apex a tactile hemisphere, and (2) an elongated tail-like part, about 180 m long. The surface of the tactile hemisphere is covered by numerous bulbous expansions, attached to it by short stalks. The base of the hemisphere is surrounded by a fringe of thin motile processes; the remaining surface of the spermatozoon is covered with long cellular processes which run more or less parallel to one another.The membrane-associated particles found on the membrane beneath the cellular processes are regularly arranged as groups of parallel strands. The external surface of the so-called peripheral granules, as revealed by freeze-etching, is smooth with a very small number of particles. Internally the particles exhibit a regular hexagonal pattern which has not been observed, so far, on any other membrane of these sperm cells.The regional specialization of the spermatozoon surface membrane in relation to sperm motility is discussed. The results obtained indicate that processes of three types: (1) bulbous expansions, (2) motile processes, and (3) cellular processes are regional specializations, all engaged in aspects of sperm motility.The technical assistance of Mr. R. Haemmerle of Balzers Research Laboratories, Mrs. F. Seif and Miss C. Pugin, is gratefully acknowledged 相似文献
277.
Summary In a survey, out of the nineteen genera of non-leguminous angiosperms that are already reported to bear actinomycete-induced nitrogen-fixing root nodules from various parts of the world, the species of seven genera (Alnus, Elaeagnus, Hippophaë, Coriaria, Datisca, Rubus and Casuarina) have been located in Pakistan and checked for nodulation. All the investigated species of the these genera, except those of Rubus and some of the introduced species of Casuarina, were found to bear nodules. In all 12 species belonging to six genera of five families have been recorded to bear actinorhizal nodules in Pakistan. 相似文献
278.
Vanadate(V) anions have been found to modulate the activity of a large number of enzymes. To elucidate these interactions, a physico-chemical study of the binding of meta-vanadate(V) with two typical proteins ovalbumin and transfusion gelatin has been taken up. The binding has been investigated by polarographic method at pHs 7.5 and 9.3, and at 30 degrees C. Values of intrinsic association constant, standard Gibb's free energy change, and the number of amino acids involved in these bindings are reported. Analysis of the binding sites has been done. 相似文献
279.
Observations on the ultrastructure ofFrankia sp. in root nodules ofDatisca cannabina L. 总被引:1,自引:1,他引:0
Summary The fine structures of the microsymbiont inside the root nodules ofDatisca cannabina have been studied by light, by transmission- and by scanning-electron microscopy. The endophyte is prokaryotic and actinomycetal in nature. The hyphae are septate and branched, diameter 0.3–0.5 m. The tips of hyphae are swollen to form electron-dense, clubshaped to filamentous vesicles, ranging in diameter: 0.4–1.4 m. The endophyte penetrates through walls of the cortial cells. The infected zone is kidney shaped and confined to one side of the acentric stele. The orientation of infection is reversed from other actinorhizae exceptCoriaria. The hyphae are near the host cell wall and vesicles are directed towards the central vacuole. Vesicles are aseptate and no collapsing of the vesicle cell wall (void area) has been observed. Vesicle clusters structures are globular with an opening at one side of the cluster. The host cell is multinucleate or contains a lobed nucleus. Groups of mitochondria are located in between the hyphae, suggesting a strong association between the host and the endophyte for energy supply and amino acid production. The consequences of the inability to separate the mitochondria from the vesicle clusters in nodule homogenates in physiological studies have been discussed.Isolated vesicles clusters showed dehydrogenase activity, indicated by the presence of formazan crystals, after incubation with NADH and NBT. Strongest reducing activity was found within the vesicles. The possible role of filamentous vesicles in nitrogen fixation has been discussed. 相似文献
280.
Bovine collagen alpha-1 is a naturally occurring extracellular matrix protein found in tendons and other connective tissues. It plays
a vital role in cell growth, differentiation, attachment, and migration. Recent findings have established that collagen alpha-1 is
involved in osteogenesis imperfecta phenotype in cattle but deep information about other members of this large family is not
available so far. So with a view to finding a new edge and attempt to figure out a correlation among the well attributed Bovine
alpha-1 collagen sequences are executed and analyzed. To do so, comparative analysis among the 28 members of collagen family
has been carried out using Computational tools. Consequently, based on the physico-chemical, secondary structural, functional
and phylogenetic classifications, we have selected collagen 12, 14 and 20 as targets for pathological conditions. These proteins
belong to the FACIT family and significantly showed low glycine and proline content, high instability and aliphatic index.
Moreover, FACIT family collagens contain multiple triple helical domains and being members of the FACIT family, bovine
collagen 12, 14, 20 do not form fibrils by themselves but they are associated to collagen 1 associated fibrils. These collagen
molecules might be crucial candidates to detect and understand the process of matrix remodeling in diseases especially in the arena
of cellular compartments. 相似文献