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121.
EG Ciolac SS Mantuani CM Neiva CEL Verardi DM Pess?a-Filho L Pimenta 《Biology of sport / Institute of Sport》2015,32(2):103-108
The aim of the present study was to analyse the usefulness of the 6-20 rating of perceived exertion (RPE) scale for prescribing and self-regulating high-intensity interval training (HIT) in young individuals. Eight healthy young subjects (age = 27.5±6.7 years) performed maximal graded exercise testing to determine their maximal and reserve heart rate (HR). Subjects then performed two HIT sessions (20 min on a treadmill) prescribed and regulated by their HR (HR: 1 min at 50% alternated with 1 min at 85% of reserve HR) or RPE (RPE: 1 minute at the 9-11 level [very light-fairly light] alternated with 1 minute at the 15-17 level [hard-very hard]) in random order. HR response and walking/running speed during the 20 min of exercise were compared between sessions. No significant difference between sessions was observed in HR during low- (HR: 135±15 bpm; RPE: 138±20 bpm) and high-intensity intervals (HR: 168±15 bpm; RPE: 170±18 bpm). Walking/running speed during low- (HR: 5.7±1.2 km · h−1; RPE: 5.7±1.3 km · h−1) and high-intensity intervals (HR: 7.8±1.9 km · h−1; RPE: 8.2±1.7 km · h−1) was also not different between sessions. No significant differences were observed in HR response and walking/running speed between HIT sessions prescribed and regulated by HR or RPE. This finding suggests that the 6-20 RPE scale may be a useful tool for prescribing and self-regulating HIT in young subjects. 相似文献
122.
An extract from rat brain has been shown to catalyze the transfer of ganglioside GM1 from sonicated vesicles to erythrocyte ghosts. It also enhanced the transfer of GM1 to a crude neuronal membrane preparation, whereas myelin took up only a very limited amount. The transfer activity was heat-labile. Similar transfer activities were found in extracts from bovine gray and white matter, that of the former being comparable to rat brain whereas the latter was greater per milligram protein. 相似文献
123.
Conservation of alternative splicing and genomic organization of the myosin alkali light-chain (Mlc1) gene among Drosophila species 总被引:3,自引:0,他引:3
The Mlc1 gene of Drosophila melanogaster encodes two MLC1 isoforms via
developmentally regulated alternative pre-mRNA splicing. In larval muscle
and tubular and abdominal muscles of adults, all of the six exons are
included in the spliced mRNA, whereas, in the fibrillar indirect flight
muscle of adult, exon 5 is excluded from the mRNA. We show that this
tissue-specific pattern of alternative splicing of the Mlc1 pre-mRNA is
conserved in D. simulans, D. pseudoobscura, and D. virilis. Isolation and
sequencing of the Mlc1 genes from these three other Drosophila species have
revealed that the overall organization of the genes is identical and that
the genes have maintained a very high level of sequence identity within the
coding region. Pairwise amino acid identities are 94%-99%, and there are no
charge changes among the proteins. Total nucleotide divergence within the
coding region of the four genes supports the accepted genealogy of these
species, but the data indicate a significantly higher rate of amino acid
replacement in the branch leading to D. pseudoobscura. A comparison of
nucleotide substitutions in the coding portions of exon 5 and exon 6, which
encode the alternative carboxyl termini of the two MLC1 isoforms, suggests
that exon 5 is subject to greater evolutionary constraints than is exon 6.
In addition to the coding sequences, there is significant sequence
conservation within the 5' and 3' noncoding DNA and two of the introns,
including one that flanks exon 5. These regions are candidates for cis-
regulatory elements. Our results suggest that evolutionary constraints are
acting on both the coding and noncoding sequences of the Mlc1 gene to
maintain proper expression and function of the two MLC1 polypeptides.
相似文献
124.
BLA Verçosa CM Lemos IL Mendonça SMMS Silva SM de Carvalho H Goto FAL Costa 《BMC veterinary research》2008,4(1):45
Background
Visceral leishmaniasis in Brazil is caused by the protozoan Leishmania (Leishmania) chagasi and it is transmitted by sandfly of the genus Lutzomyia. Dogs are an important domestic reservoir, and control of the transmission of visceral leishmaniasis (VL) to humans includes the elimination of infected dogs. However, though dogs are considered to be an important element in the transmission cycle of Leishmania, the identification of infected dogs representing an immediate risk for transmission has not been properly evaluated. Since it is not possible to treat infected dogs, they are sacrificed when a diagnosis of VL is established, a measure that is difficult to accomplish in highly endemic areas. In such areas, parameters that allow for easy identification of reservoirs that represents an immediate risk for transmission is of great importance for the control of VL transmission. In this study we aimed to identify clinical parameters, reinforced by pathological parameters that characterize dogs with potential to transmit the parasite to the vector.Results
The major clinical manifestations of visceral leishmaniasis in dogs from an endemic area were onicogriphosis, skin lesions, conjunctivitis, lymphadenopathy, and weight loss. The transmission potential of these dogs was assessed by xenodiagnosis using Lutzomyia longipalpis. Six of nine symptomatic dogs were infective to Lutzomyia longipalpis while none of the five asymptomatic dogs were infective to the sandfly. Leishmania amastigotes were present in the skin of all clinically symptomatic dogs, but absent in asymptomatic dogs. Higher parasite loads were observed in the ear and ungueal region, and lower in abdomen. The inflammatory infiltrate was more intense in the ears and ungueal regions of both symptomatic and asymptomatic dogs. In clinically affected dogs in which few or none Leishmania amastigotes were observed, the inflammatory infiltrate was constituted mainly of lymphocytes and macrophages. When many parasites were present, the infiltrate was also comprised of lymphocytes and macrophages, as well as a larger quantity of polymorphonuclear neutrophils (PMNs).Conclusion
Dogs that represent an immediate risk for transmission of Leishmania in endemic areas present clinical manifestations that include onicogriphosis, skin lesions, conjunctivitis, lymphadenopathy, and weight loss. Lymphadenopathy in particular was a positive clinical hallmark since it was closely related to the positive xenodiagnosis.125.
Survey of Malassezia sp and dermatophytes in the cutaneous microbiome of free‐ranging golden‐headed lion tamarins (Leontopithecus chrysomelas ‐ Kuhl, 1820) 下载免费PDF全文
126.
Background
Genetic variation in the human population is a key determinant of influenza disease severity. A single nucleotide polymorphism in the antiviral gene IFITM3 was linked to outcomes during the 2009 H1N1 pandemic. To identify variant host genes associated with increased virus replication and severe disease, we performed a quantitative trait locus analysis on pro-inflammatory cytokine production 48 hours after intranasal infection with highly pathogenic H5N1 influenza virus.Results
Pro-inflammatory cytokines CCL2, TNFα and IFN-α, were measured by ELISA in lung homogenates of DBA/2J (D2), C57BL/6J (B6) and 44 different BXD recombinant inbred mouse strains. Virus titer was also assessed in a subset of these animals. CCL2 (8-fold), TNFα (24-fold) and IFN-α (8-fold) concentrations varied significantly among the different BXD RI strains. Importantly, cytokine concentration correlated very well (r =0.86-0.96, P <0.0001) with virus titer suggesting that early cytokine production is due to increased virus infection and replication. Linkage analysis of cytokine concentration revealed a significant locus on chromosome 6 associated with differences in TNFα, IFN-α and CCL2 cytokine concentration (LRS =26). This locus accounted for nearly 20% of the observed phenotypic variation in the BXD population studied. Sequence and RNA expression analysis identified several candidate host genes containing missense mutations or deletions; Samd9l, Ica1, and Slc25a13. To study the role of Slc25a13, we obtained Slc25a13 knockout line, but upon challenge with H5N1 influenza virus observed no effect on CCL2 production, or morbidity and mortality.Conclusion
A novel genetic locus on chromosome 6 modulates early pro-inflammatory cytokine production and virus replication after highly pathogenic influenza virus infection. Candidate genes, Samd9l and Ica1, may be important for the control of influenza virus infection and pathogenesis.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-1017) contains supplementary material, which is available to authorized users. 相似文献127.
Background
To obtain predictions that are not biased by selection, the conditional mean of the breeding values must be computed given the data that were used for selection. When single nucleotide polymorphism (SNP) effects have a normal distribution, it can be argued that single-step best linear unbiased prediction (SS-BLUP) yields a conditional mean of the breeding values. Obtaining SS-BLUP, however, requires computing the inverse of the dense matrix G of genomic relationships, which will become infeasible as the number of genotyped animals increases. Also, computing G requires the frequencies of SNP alleles in the founders, which are not available in most situations. Furthermore, SS-BLUP is expected to perform poorly relative to variable selection models such as BayesB and BayesC as marker densities increase.Methods
A strategy is presented for Bayesian regression models (SSBR) that combines all available data from genotyped and non-genotyped animals, as in SS-BLUP, but accommodates a wider class of models. Our strategy uses imputed marker covariates for animals that are not genotyped, together with an appropriate residual genetic effect to accommodate deviations between true and imputed genotypes. Under normality, one formulation of SSBR yields results identical to SS-BLUP, but does not require computing G or its inverse and provides richer inferences. At present, Bayesian regression analyses are used with a few thousand genotyped individuals. However, when SSBR is applied to all animals in a breeding program, there will be a 100 to 200-fold increase in the number of animals and an associated 100 to 200-fold increase in computing time. Parallel computing strategies can be used to reduce computing time. In one such strategy, a 58-fold speedup was achieved using 120 cores.Discussion
In SSBR and SS-BLUP, phenotype, genotype and pedigree information are combined in a single-step. Unlike SS-BLUP, SSBR is not limited to normally distributed marker effects; it can be used when marker effects have a t distribution, as in BayesA, or mixture distributions, as in BayesB or BayesC π. Furthermore, it has the advantage that matrix inversion is not required. We have investigated parallel computing to speedup SSBR analyses so they can be used for routine applications.Electronic supplementary material
The online version of this article (doi:10.1186/1297-9686-46-50) contains supplementary material, which is available to authorized users. 相似文献128.
Esther C.H.E.T. Lucassen Alfons J.P. Smolders Ger Boedeltje Piet J J. van den Munckhof Jan CM. Roelofs 《植被学杂志》2006,17(4):425-434
Question: How does groundwater input affect plant distribution in Alnus glutinosa (black alder) carrs? Location: Alder carrs along the river Meuse, SE Netherlands. Methods: Three types of site, characterized by groundwater flow, were sampled in 17 A. glutinosa carrs. Vegetation and abiotic data (soil and water chemistry) were collected and analysed using a Canonical Correspondence Analysis. Based on the results, a laboratory experiment tested the effect of groundwater input (Ca2+) on pore water chemistry (NH4+ availability). Results: Environmental factors indicating groundwater input (Ca2+ and Fe2+), correlating with the NH+4 concentration in the pore water, best explained the variation in plant distribution. NH4+ availability was determined by Ca2+ input via the groundwater and subsequent competition for exchange sites in the sediment. As a result, nutrient‐poor seepage locations fully fed by groundwater were dominated by small iron resistant plants such as Caltha palustris and Equisetum fluviatile. More nutrient‐rich locations, fed by a combination of groundwater and surface water, allowed the growth of taller iron resistant plant species such as Carex paniculata. Nutrient‐rich locations with stagnating surface water were hardly fed by groundwater, allowing the occurrence of fast growing and less iron tolerant wetland grasses such as Glyceria fluitans and G. maxima. Conclusion: Groundwater input affects plant composition in A. glutinosa carrs along the river Meuse by determining nutrient availability (ammonium) and concentrations of toxic iron. 相似文献
129.
Several studies have indicated that olfactory responses are impeded by
amiloride. Therefore, it was of interest to see whether, and if so which,
olfactory epithelial cellular compartments have amiloride- sensitive
structures. Using ultrastructural methods that involved rapid freezing,
freeze-substitution and low temperature embedding of olfactory epithelia,
this study shows that, in the rat, this tissue is immunoreactive to
antibodies against amiloride sensitive Na(+)- channels. However, microvilli
of olfactory supporting cells, as opposed to receptor cilia, contained most
of the immunoreactive sites. Apices from which the microvilli sprout and
receptor cell dendritic knobs had much less if any of the
amiloride-antibody binding sites. Using a direct ligand-binding
cytochemical method, this study also confirms earlier ones that showed that
olfactory receptor cell cilia have Na+, K(+)-ATPase. It is proposed that
supporting cell microvilli and the receptor cilia themselves have
mechanisms, different but likely complementary, that participate in
regulating the salt concentration around the receptor cell cilia. In this
way, both structures help to provide the ambient mucous environment for
receptor cells to function properly. This regulation of the salt
concentration of an ambient fluid environment is a function that the
olfactory epithelium shares with cells of transporting epithelia, such as
those of kidney.
相似文献
130.