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1.
We have analyzed a total of 12 different global and local multiple
protein-sequence alignment methods. The purpose of this study is to
evaluate each method's ability to correctly identify the ordered series of
motifs found among all members of a given protein family. Four
phylogenetically distributed sets of sequences from the hemoglobin, kinase,
aspartic acid protease, and ribonuclease H protein families were used to
test the methods. The performance of all 12 methods was affected by (1) the
number of sequences in the test sets, (2) the degree of similarity among
the sequences, and (3) the number of indels required to produce a multiple
alignment. Global methods generally performed better than local methods in
the detection of motif patterns.
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2.
The African Black Oystercatcher Haematopus moquini is a charismatic, southern African near-endemic, wader species, that is often seen as a flagship species for coastal bird conservation, as it was recently down-listed regionally to Least Concern on the IUCN Red List of Threatened Species. To celebrate this rare conservation success story, BirdLife South Africa named it the 2018 Bird of the Year and ran a year-long programme in collaboration with the Nature’s Valley Trust highlighting aspects of the species’ biology, current threats, and conservation success. We used data collected by the Southern African Bird Atlas Project (SABAP1 and SABAP2) to examine changes in the species’ range and relative abundance, both in the records between the two projects, as well as trends within the SABAP2 sampling period (2008–2017). This case study enabled us to assess whether such metrics can accurately reflect abundance and distributional changes in a species. We found increases in the reported range and the reporting rates between the two Atlas projects, and that the SABAP2 reporting rate was stable. Regionally, across four coastal categories, the reporting rate was lowest in KwaZulu-Natal, though this region also showed an increase in the probability of reporting during the SABAP2 period. While corroborating the recent change in the species’ conservation status, we also provide good evidence that the long-term SABAP data can be used successfully to assess population trends and range changes over time. 相似文献
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Out of Africa and back again: nested cladistic analysis of human Y chromosome variation 总被引:18,自引:3,他引:15
Hammer MF; Karafet T; Rasanayagam A; Wood ET; Altheide TK; Jenkins T; Griffiths RC; Templeton AR; Zegura SL 《Molecular biology and evolution》1998,15(4):427-441
We surveyed nine diallelic polymorphic sites on the Y chromosomes of 1,544
individuals from Africa, Asia, Europe, Oceania, and the New World.
Phylogenetic analyses of these nine sites resulted in a tree for 10
distinct Y haplotypes with a coalescence time of approximately 150,000
years. The 10 haplotypes were unevenly distributed among human populations:
5 were restricted to a particular continent, 2 were shared between Africa
and Europe, 1 was present only in the Old World, and 2 were found in all
geographic regions surveyed. The ancestral haplotype was limited to African
populations. Random permutation procedures revealed statistically
significant patterns of geographical structuring of this paternal genetic
variation. The results of a nested cladistic analysis indicated that these
geographical associations arose through a combination of processes,
including restricted, recurrent gene flow (isolation by distance) and range
expansions. We inferred that one of the oldest events in the nested
cladistic analysis was a range expansion out of Africa which resulted in
the complete replacement of Y chromosomes throughout the Old World, a
finding consistent with many versions of the Out of Africa Replacement
Model. A second and more recent range expansion brought Asian Y chromosomes
back to Africa without replacing the indigenous African male gene pool.
Thus, the previously observed high levels of Y chromosomal genetic
diversity in Africa may be due in part to bidirectional population
movements. Finally, a comparison of our results with those from nested
cladistic analyses of human mtDNA and beta-globin data revealed different
patterns of inferences for males and females concerning the relative roles
of population history (range expansions) and population structure
(recurrent gene flow), thereby adding a new sex-specific component to
models of human evolution.
相似文献
5.
Myostatin (MSTN) gene duplications in Atlantic salmon (Salmo salar): evidence for different selective pressure on teleost MSTN-1 and -2 总被引:1,自引:0,他引:1
Ostbye TK Wetten OF Tooming-Klunderud A Jakobsen KS Yafe A Etzioni S Moen T Andersen O 《Gene》2007,403(1-2):159-169
Whereas the negative muscle regulator myostatin (MSTN) in mammals is almost exclusively expressed in the muscle by a single encoding gene, teleost fish possess at least two MSTN genes which are differentially expressed in both muscular and non-muscular tissues. Duplicated MSTN-1 genes have previously been identified in the tetraploid salmonid genome. From Atlantic salmon we succeeded in isolating the paralogous genes of MSTN-2, which shared about 70% identity with MSTN-1a and -1b. The salmon MSTN-2a cDNA encoded a predicted protein of 363 residues and included the conserved C-terminal bioactive domain. MSTN-2a seemed to be primarily expressed in the brain, and a functional role of teleost MSTN-2 in the neurogenesis similar to the inhibitory action of the closely related GDF-11 in the mammalian brain was proposed. In contrast, a frame-shift mutation in exon 1 of salmon MSTN-2b would lead to the synthesis of a putatively non-functional truncated protein. The absence of processed MSTN-2b mRNA in the examined tissues indicated that this gene has become a non-functional pseudogene. The differential, but partially overlapping, expression patterns of salmon MSTN-2a, -1a and -1b in muscular and non-muscular tissues are probably due to the different arrangement of the potential cis-acting regulatory elements identified in their putative promoter regions. Single and paired E-boxes in the MSTN-1b promoter were shown to bind both homo-and hetero-dimers of the myogenic regulatory factor MyoD and E47 in vitro of importance for initiating the myogenic program. Analyses of nucleotide substitution patterns indicated that the teleost MSTNs essentially have evolved under purifying selection, but a subset of amino acid sites under positive selective pressure were identified within the MSTN1 branch. The results may reflect the evolutionary forces related to adoption of the different functional roles proposed for the teleost MSTN isoforms. The phylogenetic analysis of multiple vertebrate MSTNs suggested at least two separate gene duplication events in the fish lineage. Linkage analysis of polymorphic microsatellites within intron 2 of salmon MSTN-1a and -1b mapped the two genes to different linkage groups in agreement with the tetraploid origin of the duplicated salmonid MSTN-1 and MSTN-2 genes. 相似文献
6.
Little is known about the effect of exercise training on the expression of adiponectin receptor genes in peripheral blood mononuclear cells (PBMCs). In this study, we investigated the effects of aerobic training on the expression of AdipoR1 and AidpoR2 mRNAs in PBMCs, whole body insulin sensitivity, and circulating adiponectins in men. Thirty young men were randomly assigned to either a control (n=15) or an exercise (n=15) group. Subjects assigned to the exercise group underwent a 12-week jogging and/or running programme on a motor-driven treadmill at an intensity of 60%-75% of the age-based maximum heart rate with duration of 40 minutes per session and a frequency of 5 days per week. Two-way mixed ANOVA with repeated measures was used to test any significant time-by-group interaction effects for the measured variables at p=0.05. We found significant time-by-group interaction effects for waist circumference (p=0.001), VO2max (p<0.001), fasting insulin (p=0.016), homeostasis model assessment for insulin resistance (HOMA-IR) (p=0.010), area under the curve (AUC) for insulin response during the 75-g oral glucose tolerance test (p=0.002), high-molecular weight (HMW) adiponectin (p=0.016), and the PBMC mRNA levels of AdipoR1 (p<0.001) and AdipoR2 (p=0.001). The exercise group had significantly increased mRNA levels of AdipoR1 and AdipoR2 in PBMCs, along with increased whole body insulin sensitivity and HMW adiponectin, decreased waist circumference, and increased VO2max compared with the control group. In summary, the current findings suggest that exercise training modulates the expression of AdipoR1 and AdipoR2 mRNAs in PBMCs, implying that manipulation of the expression of these genes could be a potential surrogate for lifestyle intervention-mediated improvements of whole body insulin sensitivity and glucose homeostasis. 相似文献
7.
Providing every patient with a personal primary care physician or, from the physician''s perspective, establishing a stable roster or list of patients is currently being actively debated in Canada. Norway''s system of primary care medicine, similar to Canada''s, faces many of the same problems. In 1992 a trial rostering system with blended funding (capitation, fee-for-service and user fees) was established in 4 Norwegian municipalities. After 3 years of close monitoring, the results of system evaluations have attracted strong interest. This article reports on the benefits and problems encountered with the new rostering system in Norway. If Canada is moving in the same direction, some of the lessons learned may be helpful. 相似文献
8.
Young-Bin Chen Ying-Wei Lan Tsai-Hsien Hung Lih-Geeng Chen Kong-Bung Choo Winston TK Cheng Hsuan-Shu Lee Kowit-Yu Chong 《Cell stress & chaperones》2015,20(4):643-652
Several studies of stem cell-based gene therapy have indicated that long-lasting regeneration following vessel ischemia may be stimulated through VEGFA gene therapy and/or MSC transplantation for reduction of ischemic injury in limb ischemia and heart failure. The therapeutic potential of MSC transplantation can be further improved by genetically modifying MSCs with genes which enhance angiogenesis following ischemic injury. In the present study, we aimed to develop an approach in MSC-based therapy for repair and mitigation of ischemic injury and regeneration of damaged tissues in ischemic disease. HSP70 promoter-driven VEGFA expression was induced by resveratrol (RSV) in MSCs, and in combination with known RSV biological functions, the protective effects of our approach were investigated by using ex vivo aortic ring coculture system and a 3D scaffolds in vivo model. Results of this investigation demonstrated that HSP promoter-driven VEGFA expression in MSC increased approximately 2-fold over the background VEGFA levels upon HSP70 promoter induction by RSV. Exposure of HUVEC cells to medium containing MSC in which VEGFA had been induced by cis-RSV enhanced tube formation in the treated HUVEC cells. RSV-treated MSC cells differentiated into endothelial-like phenotypes, exhibiting markedly elevated expression of endothelial cell markers. These MSCs also induced aortic ring sprouting, characteristic of neovascular formation from pre-existing vessels, and additionally promoted neovascularization at the MSC transplantation site in a mouse model. These observations support a hypothesis that VEGFA expression induced by cis-RSV acting on the HSP70 promoter in transplanted MSC augments the angiogenic effects of stem cell gene therapy. The use of an inducible system also vastly reduces possible clinical risks associated with constitutive VEGFA expression. 相似文献
9.
Cleida?A?Oliveira Rong?Nie Kay?Carnes Luiz?R?Franca Gail?S?Prins Philippa?TK?Saunders Rex?A?HessEmail author 《Reproductive biology and endocrinology : RB&E》2003,1(1):75
Background
The antiestrogen ICI 182,780 has been used successfully as an alternative experimental model for the study of estrogen action in the rodent adult male reproductive tract. Although ICI 182,780 causes severe alterations in testicular and efferent ductule morphology and function, the effects on the expression of estrogen and androgen receptors in the male have not been shown. 相似文献10.
A Prem Kumar Anirudra Ghorai Vasudev Kriplani Rabindra Kumar Dash J Aravinda Paramesh Shamanna TK Sabeer Abdul Hannan Mahesh Abhyankar Santosh Revankar 《Bioinformation》2021,17(6):652
It is of interest to evaluate the clinical characteristics, treatment patterns, clinical effectiveness, and safety of telmisartan as a monotherapy or as part of combination therapy in Indian adults (>18 years old) with hypertension. All patients were receiving telmisartan as monotherapy, or as a combination therapy for hypertension management. Demographics, risk factors, existing comorbidity, and ongoing medical therapies were retrieved from the patients’ medical records. A total of 8607 patients with hypertension (median age, 51.0 years) were part of the study. The gender distribution suggested, 5534(64.3%) patients were male, and 3073 (35.7%) were female patients. The excess salt intake (39.0%) was the most common risk factor according to the results. The analysis revealed telmisartan dual therapy (57.9%) as the most prescribed therapy, followed by monotherapy (32.5%), and triple therapy (9.6%). Further, telmisartan 40mg (21.3%) and telmisartan 40mg plus amlodipine 5mg (17.6%) were the most commonly prescribed therapies. The data suggested that only 17.2% of patients required dose titration. The mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) (mmHg) were significantly decreased with monotherapy (mean change: 19.8 [15.1] mmHg and 8.8[8.2] mmHg), dual therapy (mean change: 23.7 [16.6] mmHg and 10.3[8.5] mmHg), and triple therapy (mean change: 28.6 [19.0] mmHg and 12.1[10.8] mmHg) after the treatment (P<0.001). A total of 98.4% of the patients were compliant, and 97.6% achieved the target blood pressure goal with telmisartan-based therapy. There were 157 adverse events reported altogether. The Physicians'' global evaluation of efficacy and tolerability showed the majority of the patients receiving telmisartan-based therapy on a good to excellent scale. Telmisartan used as a monotherapeutic agent or as a part of combination therapy was successful and effective in reducing blood pressure and achieving the blood pressure target. Irrespective of the patient’s age, duration, and stages of hypertension, the study resulted in a good to excellent scale in efficacy and tolerability in the Indian patients having hypertension. 相似文献