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51.
Cavalleri MT Burgi K Cruz JC Jordão MT Ceroni A Michelini LC 《American journal of physiology. Regulatory, integrative and comparative physiology》2011,301(4):R958-R966
We showed previously that oxytocinergic (OTergic) projections from the hypothalamic paraventricular nucleus (PVN) to the dorsal brain stem mediate training-induced heart rate (HR) adjustments and that beneficial effects of training are blocked by sinoaortic denervation (SAD; Exp Physiol 94: 630-640; 1103-1113, 2009). We sought now to determine the combined effect of training and SAD on PVN OTergic neurons in spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats. Rats underwent SAD or sham surgery and were trained (55% of maximal capacity) or kept sedentary for 3 mo. After hemodynamic measurements were taken at rest, rats were deeply anesthetized. Fresh brains were frozen and sliced to isolate the PVN; samples were processed for OT expression (real-time PCR) and fixed brains were processed for OT immunofluorescence. In sham rats, training improved treadmill performance and increased the gain of baroreflex control of HR. Training reduced resting HR (-8%) in both groups, with a fall in blood pressure (-10%) only in SHR rats. These changes were accompanied by marked increases in PVN OT mRNA expression (3.9- and 2.2-fold in WKY and SHR rats, respectively) and peptide density in PVN OTergic neurons (2.6-fold in both groups), with significant correlations between OT content and training-induced resting bradycardia. SAD abolished PVN OT mRNA expression and markedly reduced PVN OT density in WKY and SHR. Training had no effect on HR, PVN OT mRNA, or OT content following SAD. The chronic absence of inputs from baroreceptors and chemoreceptors uncovers the pivotal role of afferent signaling in driving both the plasticity and activity of PVN OTergic neurons, as well as the beneficial effects of training on cardiovascular control. 相似文献
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53.
The use of alternative soilless media for the production of potted plants requires knowledge of their physical and chemical characteristics to result in the best conditions for plant growth. We investigated the use of alternative soilless media based on river waste and Sphagnun sp. and Carex sp. from Argentinean peatlands on Petuniaxhybrida and Impatiens wallerana production at two fertilization levels (200 and 400mgl(-1)N). River waste or 'temperate peat' is the name given to a material, resulting from the accumulation of aquatic plant residues under an anaerobic subtropical environment, which is dredged from river banks. Our results showed that alternative substrates based on river waste can be used to grow high quality plants. This result was not fully explained on the basis of established methods to evaluate substrate quality. Highly concentrated fertigation solution decreased the substrate quality parameters and plant growth. Nitrate leaching from the alternative substrates containing river waste was lower than the standard peat-based materials, which makes river waste desirable from a sustainable pot production system perspective. River waste and Carex peat are suitable alternatives to Sphagnum peat from the Northern Hemisphere. 相似文献
54.
Interleukin–10 promoter haplotypes are differently distributed in the Brazilian versus the Dutch population 总被引:4,自引:0,他引:4
Moraes MO Santos AR Schonkeren JJ Vanderborght PR Ottenhoff TH Moraes ME Moraes JR Sampaio EP Sarno EN Huizinga TW 《Immunogenetics》2003,54(12):896-899
The frequency of five different single nucleotide polymorphisms of the promoter interleukin-10 (IL-10) gene (-3575, -2849, 2763, -1082, -819) was compared between two healthy populations, one originating from the Netherlands and one from Rio de Janeiro, Brazil. A total of 321 Caucasian Dutch individuals and 293 Brazilians, grouped as Afro-Brazilians and Euro-Brazilians, were genotyped using PCR-RFLP. The frequencies of the genotypes in the Brazilian population were different (P<0.05) from the frequencies in the Dutch population in all but one (-2763) genotype. The comparison of genotype frequencies between Afro- and Euro-Brazilians did not demonstrate any differences. The haplotype combination of the most-distant three polymorphisms showed strong linkage disequilibrium. All eight possible combinations were observed in Brazilians, but only seven in Dutch Caucasians. The haplotype frequencies were also significantly different between Brazilians when compared with Dutch and also between Euro-Brazilians and Dutch. No differences were observed in haplotype frequencies between Afro-Brazilians and Euro-Brazilians. The -3575T/-2849G/-2763C is more frequent, while the AAA haplotype was much less represented in the Brazilian than in the Dutch population. The haplotype TAC, which was described in African-Americans, was observed only in Brazilians, almost exclusively among those of European origin. The results corroborate the data indicating that the Brazilian population exhibits a genetic admixture of Africans, Europeans, and Amerindians, and the data may serve as a background for clinical and immunological studies involving the IL-10 locus. 相似文献
55.
Bruno Cavalleri Giancarlo Volpe Giogio Tuan Marisa Berti Francesco Parenti 《Current microbiology》1978,1(5):319-324
Two chlorophenyl-containing antibiotics have been isolated from a strain ofActinoplanes (ATCC 33002). Antibiotic A 15104 Y is a chlorinated phenylpyrrole compound whose structure has been confirmed by chemical
synthesis. Antibiotic A 15104 Z is a chlorophenol derivative for which a structural formula is proposed on the basis of its
physicochemical properties. A 15104 Y shows antimicrobial activity against Gram-positive, Gram-negative, and acid-fast bacteria,
yeasts, fungi, and protozoa, while A 15104 Z possesses a low activity against Gram-positive bacteria andTrichophyton. A 15104 Y has a weak activity in curing experimentally infected mice, at a dose that is one-fifth the LD50 for the same species. This is the first example of a chloropyrrole derivative isolated from an actinomycete. 相似文献
56.
Merighi A Bardoni R Salio C Lossi L Ferrini F Prandini M Zonta M Gustincich S Carmignoto G 《Developmental neurobiology》2008,68(4):457-475
A subset of primary sensory neurons produces BDNF, which is implicated in control of nociceptive neurotransmission. We previously localized full-length trkB receptors on their terminals within lamina II. To functionally study these receptors, we here employed patch-clamp recordings, calcium imaging and immunocytochemistry on slices from 8-12 days post-natal rats. In this preparation, BDNF (100-500 ng/mL) enhances the release of sensory neurotransmitters (glutamate, substance P, CGRP) in lamina II by acting on trkB receptors expressed by primary afferent fibers of the peptidergic nociceptive type (PN-PAFs). Effect was blocked by trk antagonist K252a or anti-trkB antibody clone 47. A pre-synaptic mechanism was demonstrated after (i) patch-clamp recordings where the neurotrophin induced a significant increase in frequency, but not amplitude, of AMPA-mediated mEPSCs, (ii) real time calcium imaging, where sustained application of BDNF evoked an intense response in up to 57% lamina II neurons with a significant frequency rise. Antagonists of ionotropic glutamate receptors and NK(1) receptors completely inhibited the calcium response to BDNF. Reduction of CGRP (a specific marker of PN-PAFs) and substance P content in dorsal horn following BDNF preincubation, and analysis of the calcium response after depletion with capsaicin, confirmed that the neurotrophin presynaptically enhanced neurotransmitter release from PN-PAFs. This is the first demonstration that trkB receptors expressed by PN-PAF terminals in lamina II are functional during postnatal development. Implications of this finding are discussed considering that BDNF can be released by these same terminals and microglia, a fraction of which (as shown here) contains BDNF also in unactivated state. 相似文献
57.
The strong influence of collection bias on biodiversity knowledge shortfalls of Brazilian terrestrial biodiversity 下载免费PDF全文
Ubirajara Oliveira Adriano Pereira Paglia Antonio D. Brescovit Claudio J. B. de Carvalho Daniel Paiva Silva Daniella T. Rezende Felipe Sá Fortes Leite João Aguiar Nogueira Batista João Paulo Peixoto Pena Barbosa João Renato Stehmann John S. Ascher Marcelo Ferreira de Vasconcelos Paulo De Marco Jr Peter Löwenberg‐Neto Priscila Guimarães Dias Viviane Gianluppi Ferro Adalberto J. Santos 《Diversity & distributions》2016,22(12):1232-1244
58.
Alann Thaffarell Portilho Souza Gileade Pereira Freitas Helena Bacha Lopes Emanuela Prado Ferraz Fabiola Singaretti Oliveira Marcio Mateus Beloti Adalberto Luiz Rosa 《Cytotherapy》2018,20(10):1267-1277
Background aims
Regenerative medicine strategies based on cell therapy are considered a promising approach to repair bone defects. The aims of this study were to evaluate the effect of subculturing on the osteogenic potential of osteoblasts derived from newborn rat calvaria and the effect of these osteoblasts on bone repair of rat calvaria defects.Methods
Cells were obtained from 50 newborn rat calvaria, and primary osteoblasts (OB) were compared with first passage (OB-P1) in terms of osteogenic potential by assaying cell proliferation, alkaline phosphatase (ALP) activity, extracellular matrix mineralization and gene expression of the osteoblastic markers RUNX2, ALP, osteocalcin and bone sialoprotein. Then, 5-mm calvaria defects were created in 24 Wistar rats, and after 2 weeks, they were locally injected with 50 µL of phosphate-buffered saline containing either 5?×?106 osteoblasts (OB-P1, n?=?12) or no cells (control, n?=?12). Four weeks post-injection, the bone formation was evaluated by micro-computed tomography and histological analyses. Data were compared by analysis of variance, followed by the Student-Newman-Keuls's test or Student's t-test (P ≤ 0.05).Results
OB-P1 showed high proliferation and ALP activity, and despite the reduced gene expression of osteoblastic markers and extracellular matrix mineralization compared with OB, they displayed osteogenic potential, being a good choice for injection into calvaria defects. The micro-tomographic and histological data showed that defects treated with OB-P1 presented higher bone formation compared with control defects.Discussion
Our results indicate that cells derived from newborn rat calvaria retain osteoblastic characteristics after subculturing and that these osteoblasts stimulate bone repair in a rat calvaria defect model. 相似文献59.
Taylor G. Donaldson Adalberto A. Pèrez de León Andrew I. Li Ivan Castro-Arellano Edward Wozniak William K. Boyle Reid Hargrove Hannah K. Wilder Hee J. Kim Pete D. Teel Job E. Lopez 《PLoS neglected tropical diseases》2016,10(2)
BackgroundOrnithodoros turicata is a veterinary and medically important argasid tick that is recognized as a vector of the relapsing fever spirochete Borrelia turicatae and African swine fever virus. Historic collections of O. turicata have been recorded from Latin America to the southern United States. However, the geographic distribution of this vector is poorly understood in relation to environmental variables, their hosts, and consequently the pathogens they transmit.MethodologyLocalities of O. turicata were generated by performing literature searches, evaluating records from the United States National Tick Collection and the Symbiota Collections of Arthropods Network, and by conducting field studies. Maximum entropy species distribution modeling (Maxent) was used to predict the current distribution of O. turicata. Vertebrate host diversity and GIS analyses of their distributions were used to ascertain the area of shared occupancy of both the hosts and vector.
Conclusions and Significance
Our results predicted previously unrecognized regions of the United States with habitat that may maintain O. turicata and could guide future surveillance efforts for a tick capable of transmitting high–consequence pathogens to human and animal populations. 相似文献60.