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81.
82.
The purse-web spider genus Calommata Lucas, 1837 is revised in the Afrotropical Region. Following examination of the female type material, Calommata transvaalica Hewitt, 1916 is removed from synonymy with Calommata simoni Pocock, 1903 and revalidated. The females of both species are redescribed and their males described for the first time. While Calommata simoni is very widespread across tropical Africa, Calommata transvaalica is endemic to northern South Africa. Four new species are described, all known only from males: Calommata megaesp. n. (Zimbabwe), Calommata meridionalissp. n. (South Africa), Calommata namibicasp. n. (Namibia) and Calommata tibialissp. n. (Ivory Coast and Togo). Notes are presented on the biology of each species.  相似文献   
83.
GeneReporter is a web tool that reports functional information and relevant literature on a protein-coding sequence of interest. Its purpose is to support both manual genome annotation and document retrieval. PubMed references corresponding to a sequence are detected by the extraction of query words from UniProt entries of homologous sequences. Data on protein families, domains, potential cofactors, structure, function, cellular localization, metabolic contribution and corresponding DNA binding sites complement the information on a given gene product of interest. Availability and implementation: GeneReporter is available at http://www.genereporter.tu-bs.de. The web site integrates databases and analysis tools as SOAP-based web services from the EBI (European Bioinformatics Institute) and NCBI (National Center for Biotechnology Information).  相似文献   
84.

Objective

Aging is associated with increased oxidative stress levels and impaired neovascularization following ischemia. CuZnSOD has an important role to limit oxidative stress in the vasculature. Here we investigated the role of CuZnSOD for the modulation of ischemia-induced neovascularisation during aging.

Methods and Results

Hindlimb ischemia was surgically induced in young (2- month-old) or older (8-month-old) wild type (WT) and CuZnSOD−/− mice. We found that blood flow recovery after ischemia and vascular density in ischemic muscles were significantly reduced in older compared to young WT mice. Both in young and older mice, CuZnSOD deficiency led to a further reduction of neovascularization. Accordingly, the resulting neovascularisation potential in a young CuZnSOD−/− mouse was similar to that of an older WT mouse. Oxidative stress levels were also increased to similar levels in the ischemic muscles of young CuZnSOD−/− and older WT mice. To identify potential mechanisms involved, we investigated the effect of aging and CuZnSOD deficiency on the number and the function of endothelial progenitor cells (EPCs). Both aging and CuZnSOD deficiency were associated with reduced number of bone marrow and peripheral EPCs. The effect of moderate aging alone on specific functional activities of EPCs (migration, integration into tubules) was modest. However, CuZnSOD deficiency was associated with severe age-dependent defects in EPC functional activities.

Conclusions

CuZnSOD deficiency is associated with accelerated vascular aging and impaired ischemia-induced neovascularization. Our results suggest that in the context of aging, CuZnSOD has an essential role to protect against excessive oxidative stress in ischemic tissues and preserve the function of EPCs.  相似文献   
85.

Background

In school-aged children with cystic fibrosis (CF) structural lung damage assessed using chest CT is associated with abnormal ventilation distribution. The primary objective of this analysis was to determine the relationships between ventilation distribution outcomes and the presence and extent of structural damage as assessed by chest CT in infants and young children with CF.

Methods

Data of infants and young children with CF diagnosed following newborn screening consecutively reviewed between August 2005 and December 2009 were analysed. Ventilation distribution (lung clearance index and the first and second moment ratios [LCI, M1/M0 and M2/M0, respectively]), chest CT and airway pathology from bronchoalveolar lavage were determined at diagnosis and then annually. The chest CT scans were evaluated for the presence or absence of bronchiectasis and air trapping.

Results

Matched lung function, chest CT and pathology outcomes were available in 49 infants (31 male) with bronchiectasis and air trapping present in 13 (27%) and 24 (49%) infants, respectively. The presence of bronchiectasis or air trapping was associated with increased M2/M0 but not LCI or M1/M0. There was a weak, but statistically significant association between the extent of air trapping and all ventilation distribution outcomes.

Conclusion

These findings suggest that in early CF lung disease there are weak associations between ventilation distribution and lung damage from chest CT. These finding are in contrast to those reported in older children. These findings suggest that assessments of LCI could not be used to replace a chest CT scan for the assessment of structural lung disease in the first two years of life. Further research in which both MBW and chest CT outcomes are obtained is required to assess the role of ventilation distribution in tracking the progression of lung damage in infants with CF.  相似文献   
86.
During postnatal maturation, there is an increase in renal brush border membrane vesicle (BBMV) osmotic water permeability and a parallel increase in aquaporin-1 (AQP1) protein abundance. The mechanisms responsible for these changes remain unknown. Because serum glucocorticoid levels rise postnatally and have previously been linked to other maturational changes in renal function, we examined the effects of glucocorticoids on osmotic (Pf) and diffusional (P(DW)) water permeability and AQP1 protein abundance of renal BBMV. Neonatal rabbits were treated with dexamethasone (10 microg/100 g) for three days and compared with control neonates and adults. Pf and P(DW) were measured at 20 degrees C with a stopped-flow apparatus using light-scattering and aminonaphthalene trisulfonic acid (ANTS) fluorescence, respectively. Pf was significantly higher in BBMV from dexamethasone-treated neonates compared with vehicle-treated neonates, but remained lower than in BBMV from adults (P<0.05). P(DW) in dexamethasone and vehicle-treated neonatal BBMV was lower than in adult BBMV. Pf/P(DW) ratio increased from neonate (5.1+/-0.3) to dexamethasone (7.0+/-0.1) and adult BBMV (6.3+/-0.1). AQP1 expression was increased by dexamethasone treatment to adult levels. Membrane fluidity, which is inversely related to generalized polarization (GP) of steady-state laurdan fluorescence, was significantly higher in neonatal BBMV than both dexamethasone and adult BBMV (GP: neonate 0.285+/-0.002, dexamethasone treatment 0.302+/-0.006, and adult 0.300+/-0.005; P<0.05). These combined results show that dexamethasone-treatment during days 4-7 of life increases BBMV water permeability despite a decrease in membrane fluidity. This occurs by increasing channel-mediated water transport, as reflected in an increase in AQP1 protein abundance and a higher Pf/P(DW) ratio. This mimics the maturational changes and suggests a physiological role for glucocorticoids in maturation of proximal tubule water transport.  相似文献   
87.
A rapid and simple procedure for enantioselective preparation of 2- and 3-substituted 2,3-dihydro[1,4]dioxino[2,3-b]pyridine derivatives (A and B, respectively) is described. The enantiomeric purity of each isomer was determined by capillary electrophoresis using a dual-cyclodextrin system (S-beta-CD/beta-CD) dissolved in formic acid-ammonia buffer (pH 4, ionic strength 50 mM).  相似文献   
88.
The objective of this experiment was to determine the effect of a 5-day progesterone priming prior to a GnRH-PGF2alpha treatment on reproductive performance of anestrous goats. Thirty-six Mountain Black goats were randomly assigned in a 2 x 2 factorial arrangement and were administered intravaginally on day -12, either with 300 mg progesterone inserts (CGPE and CGP) or with 0 mg progesterone (GPE and GP) for 5 days. On day -6, the goats were injected with 100 microg GnRH, followed 6 days later by 15 mg PGF2alpha (day 0), the time at which the goats in the CGPE and GPE groups were administered 300 IU eCG injections and those in CGP and GP groups were administered the control solution. The goats were exposed to four fertile bucks at 0 h and were checked for breeding marks at 6-h intervals for 72 h. Blood samples were collected from all goats for progesterone analysis. Progesterone concentrations increased only in CGPE and CGP during the period of device insertion but remained low in GPE and GP groups (P < 0.001). Progesterone levels at the time of GnRH injection on day -6 were basal (0.2 +/- 0.04 ng.mL-1) among the groups and began to increase starting on day -2. Day 0 progesterone concentrations differed (P < 0.05) among groups and were significantly influenced by CIDR-G (P < 0.001). A similar proportion of goats expressed estrus and intervals to detected estrus were shorter (P < 0.05) in the CGPE and GPE groups than in GP with no difference between the CGPE, CGP and GPE or between CGP and GP groups. The number of goats ovulating based upon elevated progesterone levels on day 0 was significantly greater (P = 0.002) in CGPE (9/9) and CGP (9/9) than GPE (6/9) and GP (5/9) groups and was significantly influenced by CIDR-G (P = 0.03). All pregnant goats had elevated progesterone concentration on day 0 and none of the goats with basal progesterone levels became pregnant. Pregnancy and kidding rates, twinning percentage and the number of kids born per goat exposed were greater (P < 0.05) among goats treated with progesterone and eCG. In conclusion, progesterone priming and eCG are essential for producing higher rates of pregnancy and kidding in GnRH-PGF2alpha-treated anestrous goats.  相似文献   
89.
Human immunity against Plasmodium falciparum malaria is mediated by IgG antibodies. One of the major targets of protective antibodies is the MSP-3 protein. Anti-MSP-3 human monoclonal antibodies could therefore be valuable for passive immunotherapy, particularly of drug resistant malaria. Human monoclonal antibodies were previously produced in the Hu-SPL-SCID model reconstituted with human splenocytes, immunized by highly immunogenic neo-antigen or a recall antigen. We report here that this model can also be successfully employed to induce human antibody-secreting cells specific of low immunogenicity neo-antigens, such as MSP-3. These cells represent a new and valuable source of human monoclonal anti-malaria antibodies.  相似文献   
90.
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