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91.
Amlodipine reduces blood pressure during dynamic resistance exercise in hypertensive patients 下载免费PDF全文
D. R. Souza R. S. Gomides L. A. R. Costa A. C. C. Queiroz S. Barros K. C. Ortega D. Mion Jr T. Tinucci C. L. M. Forjaz 《Scandinavian journal of medicine & science in sports》2015,25(1):53-60
This study investigated the effect of the dihydropyridine calcium channel antagonist, amlodipine, on blood pressure (BP) during resistance exercise performed at different intensities in hypertensives. Eleven hypertensives underwent 4 weeks of placebo and amlodipine (random double‐blinded crossover design). In each phase, they performed knee extension exercise until exhaustion following three protocols: one set at 100% of 1 RM (repetition maximum), three sets at 80% of 1 RM, and three sets at 40% of 1 RM. Intraarterial BP was measured before and during exercise. Amlodipine reduced maximal systolic/diastolic BP values achieved at all intensities (100% = 225 ± 6/141 ± 3 vs. 207 ± 6/130 ± 6 mmHg; 80% = 289 ± 8/178 ± 5 vs. 273 ± 10/169 ± 6 mmHg; 40% = 289 ± 10/176 ± 8 vs. 271 ± 11/154 ± 6 mmHg). Amlodipine blunted the increase in diastolic BP that occurred during the second and third sets of exercise at 40% of 1RM (+75 ± 6 vs. +61 ± 5 mmHg and +78 ± 7 vs. +64 ± 5 mmHg, respectively). Amlodipine was effective in reducing the absolute values of systolic and diastolic BP during resistance exercise and in preventing the progressive increase in diastolic BP that occurs over sets of low‐intensity exercise. These results suggest that systemic vascular resistance is involved in BP increase during resistance exercise, and imply that hypertensives receiving amlodipine are at lower risk of increased BP during resistance exercise than non‐medicated patients. 相似文献
92.
Paulo Ernando Ferraz Cavalcanti Michel Pompeu Barros de Oliveira Sá Cecília Andrade dos Santos Isaac Melo Esmeraldo Mariana Leal Chaves Ricardo Felipe de Albuquerque Lins Ricardo de Carvalho Lima 《Brazilian Journal Of Cardiovascular Surgery》2015,30(2):148-158
Objective
To determine whether stratification of complexity models in congenital heart surgery (RACHS-1, Aristotle basic score and STS-EACTS mortality score) fit to our center and determine the best method of discriminating hospital mortality.Methods
Surgical procedures in congenital heart diseases in patients under 18 years of age were allocated to the categories proposed by the stratification of complexity methods currently available. The outcome hospital mortality was calculated for each category from the three models. Statistical analysis was performed to verify whether the categories presented different mortalities. The discriminatory ability of the models was determined by calculating the area under the ROC curve and a comparison between the curves of the three models was performed.Results
360 patients were allocated according to the three methods. There was a statistically significant difference between the mortality categories: RACHS-1 (1) - 1.3%, (2) - 11.4%, (3)-27.3%, (4) - 50 %, (P<0.001); Aristotle basic score (1) - 1.1%, (2) - 12.2%, (3) - 34%, (4) - 64.7%, (P<0.001); and STS-EACTS mortality score (1) - 5.5 %, (2) - 13.6%, (3) - 18.7%, (4) - 35.8%, (P<0.001). The three models had similar accuracy by calculating the area under the ROC curve: RACHS-1- 0.738; STS-EACTS-0.739; Aristotle- 0.766.Conclusion
The three models of stratification of complexity currently available in the literature are useful with different mortalities between the proposed categories with similar discriminatory capacity for hospital mortality. 相似文献93.
94.
A. Keshavarzian MD F. L. Iber MD P. Greer RT J. Wobbteton RNNP 《Alcoholism, clinical and experimental research》1986,10(4):432-435
Nausea and vomiting are common complaints in chronic alcoholics. Autonomic neuropathy and esophageal motor abnormalities are frequently observed in chronic alcoholics, but gastric emptying has not been studied in these patients. Gastric emptying of a solid meal was measured, using 99mTc-sulfur colloid cooked in a scrambled egg, in 10 male chronic alcoholics with upper gastrointestinal complaints of nausea and vomiting. All patients were adequately nourished, recently drinking, but just over withdrawal and free of clinical peripheral neuropathy. Gastric emptying in 10 alcoholics was similar to 5 normal controls (t 1/2 115 +/- 12 versus 107 +/- 8 min). These data suggest that upper gastrointestinal symptoms in chronic alcoholics are not related to gastric motor dysfunction. 相似文献
95.
B-chronic lymphocytic leukemia (CLL) patients frequently suffer from moderate to severe hypogammaglobulinemia. This complication is a serious cause of morbidity and mortality in this disorder. There is recent evidence that natural killer (NK) cells modulate B-cell immunoglobin (Ig) synthesis/secretion. The authors therefore evaluated the circulating NK cells from B-CLL patients on their ability to regulate mitogen-induced B-cell Ig synthesis. Blood, NK cells (CD16+, CD3-) from three B-CLL patients with hypogammaglobulinemia were able to clearly down-regulate the pokeweed mitogen (PWM)-induced-B-cell Ig secretion. In contrast, CD16+, CD3- cells from age-sex-matched controls or B-CLL patients with normal Ig were either nonregulatory or enhanced mitogen-induced B-cell Ig secretion. An alternative explanation for hypogammaglobulinemia in B-CLL patients is the immunomodulation of B- cell Ig production/secretion by CD16+, CD3- blood cells. 相似文献
96.
Exenatide and Sitagliptin Decrease Interleukin 1β, Matrix Metalloproteinase 9, and Nitric Oxide Synthase 2 Gene Expression But Does Not Reduce Alveolar Bone Loss in Rats With Periodontitis 下载免费PDF全文
Renata M. Moraes Gabriela M. G. Lima Felipe E. Oliveira Ana Carolina V. Brito Rodrigo C. Pereira Luciane D. Oliveira Patrícia P. Barros Gilson C. N. Franco Ana Lia Anbinder 《Journal of periodontology》2015,86(11):1287-1295
Background: New drugs for the treatment of diabetes, glucagon‐like peptide‐1 (GLP‐1) receptor agonists and inhibitors of dipeptidyl peptidase‐4 (DPP‐4) have shown pleiotropic effects on bone metabolism and anti‐inflammatory properties. The aim of this study is to evaluate the effects of exenatide (GLP‐1 agonist) and sitagliptin (DPP‐4 inhibitor) during periodontitis induction by ligature insertion in rats. Methods: Forty rats were divided into four groups: 1) animals with induced periodontitis that received exenatide (EG); 2) animals with induced periodontitis that received sitagliptin (SG); 3) animals with induced periodontitis and without drug treatment (LG); and 4) animals without induced periodontitis and without drug treatment (controls). The drugs were administered for 28 days. On the day the animals were sacrificed, blood was collected for analysis of glucose and DPP‐4 levels. The gene expressions of prostaglandin‐endoperoxide synthase 2, tissue inhibitor of metalloproteinase 1, Dpp4, nitric oxide synthase 2 (Nos2), interleukin 1β (Il1b), and matrix metalloproteinase 9 (Mmp9) in the gingiva; support and alveolar bone loss; connective tissue attachment; and the quantity of gingival collagen were evaluated. Results: Exenatide and sitagliptin treatments have led to a lower percentage of weight gain but did not influence glycemia. Sitagliptin reduced the serum concentration of DPP‐4. Interestingly, although the gene expression profile has revealed a downregulation of Mmp9, Nos2, and Il1b in both EG and SG compared to LG, a significant protective effect was not observed on alveolar bone and collagen tissue in this model. Conclusion: Regardless of the reduction of the expression of Il1b, Nos2, and Mmp9, the drugs were not effective in the stabilization or reduction of alveolar bone loss and collagen degradation in rats. 相似文献
97.
Silvia T Elias Gabriel A Borges Danilo A Amorim Daniela F Rêgo Luiz A Simeoni Dâmaris Silveira Yris Maria Fonseca-Bazzo José E Paula Christopher William Fagg Ivelone M C Barros Wenzel C Abreu Décio S Pinto-Júnior Pérola O Magalhães Francisco A R Neves Adriana Lofrano-Porto Eliete N S Guerra 《Clinical oral investigations》2015,19(3):637-646
98.
Reconstruction of the Alveolar Buccal Bone Plate in Compromised Fresh Socket after Immediate Implant Placement Followed by Immediate Provisionalization 下载免费PDF全文
Rafael Scaf de Molon DDS MS Erica Dorigatti de Avila DDS Luiz Antonio Borelli de Barros‐Filho DDS Weber Adad Ricci DDS MS PhD Sotirios Tetradis PhD Joni Augusto Cirelli DDS MS PhD Luiz Antonio Borelli de Barros DDS MS PhD 《Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry ... [et al.]》2015,27(3):122-135
99.
Daria Soroka Inès Li de la Sierra-Gallay Vincent Dubée Sébastien Triboulet Herman van Tilbeurgh Fabrice Compain Lluis Ballell David Barros Jean-Luc Mainardi Jean-Emmanuel Hugonnet Michel Arthur 《Antimicrobial agents and chemotherapy》2015,59(9):5714-5720
Combinations of β-lactams with clavulanate are currently being investigated for tuberculosis treatment. Since Mycobacterium tuberculosis produces a broad spectrum β-lactamase, BlaC, the success of this approach could be compromised by the emergence of clavulanate-resistant variants, as observed for inhibitor-resistant TEM variants in enterobacteria. Previous analyses based on site-directed mutagenesis of BlaC have led to the conclusion that this risk was limited. Here, we used a different approach based on determination of the crystal structure of β-lactamase BlaMAb of Mycobacterium abscessus, which efficiently hydrolyzes clavulanate. Comparison of BlaMAb and BlaC allowed for structure-assisted site-directed mutagenesis of BlaC and identification of the G132N substitution that was sufficient to switch the interaction of BlaC with clavulanate from irreversible inactivation to efficient hydrolysis. The substitution, which restored the canonical SDN motif (SDG→SDN), allowed for efficient hydrolysis of clavulanate, with a more than 104-fold increase in kcat (0.41 s−1), without affecting the hydrolysis of other β-lactams. Mass spectrometry revealed that acylation of BlaC and of its G132N variant by clavulanate follows similar paths, involving sequential formation of two acylenzymes. Decarboxylation of the first acylenzyme results in a stable secondary acylenzyme in BlaC, whereas hydrolysis occurs in the G132N variant. The SDN/SDG polymorphism defines two mycobacterial lineages comprising rapidly and slowly growing species, respectively. Together, these results suggest that the efficacy of β-lactam–clavulanate combinations may be limited by the emergence of resistance. β-Lactams active without clavulanate, such as faropenem, should be prioritized for the development of new therapies. 相似文献
100.
Gilberto Sabino-Santos Jr Felipe Gon?alves Motta Maia Thallyta Maria Vieira Renata de Lara Muylaert Sabrina Miranda Lima Cristieli Barros Gon?alves Patricia Doerl Barroso Maria Norma Melo Colleen B. Jonsson Douglas Goodin Jorge Salazar-Bravo Luiz Tadeu Moraes Figueiredo 《The American journal of tropical medicine and hygiene》2015,93(2):404-406
Hantaviruses are zoonotic viruses harbored by rodents, bats, and shrews. At present, only rodent-borne hantaviruses are associated with severe illness in humans. New species of hantaviruses have been recently identified in bats and shrews greatly expanding the potential reservoirs and ranges of these viruses. Brazil has one of the highest incidences of hantavirus cardiopulmonary syndrome in South America, hence it is critical to know what is the prevalence of hantaviruses in Brazil. Although much is known about rodent reservoirs, little is known regarding bats. We captured 270 bats from February 2012 to April 2014. Serum was screened for the presence of antibodies against a recombinant nucleoprotein (rN) of Araraquara virus (ARAQV). The prevalence of antibody to hantavirus was 9/53 with an overall seroprevalence of 17%. Previous studies have shown only insectivorous bats to harbor hantavirus; however, in our study, of the nine seropositive bats, five were frugivorous, one was carnivorous, and three were sanguivorous phyllostomid bats.Hantaviruses (family Bunyaviridae) are present throughout the globe in rodents, bats, and shrews.1 Humans exposed to rodent excreta from hantaviral reservoirs may develop life-threatening diseases. However, none of the other reservoirs are associated with human illness presently.1,2 Bats (order Chiroptera) are known to harbor a broad diversity of emerging zoonotic pathogens.2 Their ability to fly and social behavior favors maintenance, evolution, and spread of pathogens.1,2 The prevailing hypothesis has been that hantaviruses have coevolved with their rodent reservoirs over millions of years.1,3 With the recognition of new species of hantavirus in bats in Africa and Asia,4 Guo and others5 hypothesized that hantaviruses originated primarily in bats and then spilled over into rodents and shrews, but it seems that shrews are the original hosts from which the viruses jumped into both rodents and bats.3 To determine if New World bats in Brazil may harbor hantaviruses, we screened bat sera for antibodies that react against the recombinant nucleoprotein (rN) of Araraquara hantavirus (ARAQV).Bats were collected at five ecologically distinct sites in the northeast region of São Paulo state (sites 1–3) and north region of Minas Gerais state (sites 4 and 5), southeastern Brazil (Figure 1
and 9 and one specimen per species by trap-night was anesthetized to collect blood by cardiac puncture; blood samples were stored in cryovials and flash-frozen in liquid nitrogen. At sites 4 and 5, five specimens per trap-night were randomly selected for blood collection. All bats were handled and sampled according to Sikes and others10 guidelines. This research project, along with its procedures and protocols, is in accordance with Brazilian environment and wildlife protection laws and regulations, and have been approved by the Chico Mendes Institute of Biodiversity Conservation (Ministry of Environment, Brasília, Distrito Federal, Brazil.), protocols nos. 19838-1 and 41709-3. It has also been approved by the Ethics Committee for Animal Research of University of São Paulo and Federal University of Minas Gerais (nos. 020/2011 and 333/2013, respectively). From 270 captured bats, 53 were bled for detection of immunoglobulin G (IgG) antibodies to rN-ARAQV by indirect enzyme-linked immunosorbent assay (ELISA) using anti-bat (Bethyl Laboratories, Inc., Montgomery, TX) secondary antibody. This ELISA, as previously described, showed 97.2% sensitivity, 100% specificity, 100% positive predictive value, and 98.1% negative predictive value when compared with an IgG-ELISA using rN antigen of Andes virus, which is the serological test for hantavirus most used in South America.11,12Open in a separate windowFigure 1.Study areas, highlighting the states of São Paulo and Minas Gerais in southeastern Brazil. The map shows cities where bats have been captured.
Open in a separate windowJES = Jatai Ecological Station; LGEP = Lapa Grande Ecological Park; MG = Minas Gerais state; NEF = Nova Esperança Farm; SEP = Sapucai Ecological Park; SGF = Santa Gabriela Farm; SP = Sao Paulo state.*Cerrado = Brazilian savanna-like biome.†Dry forest = deciduous seasonal forest.Nine bats had IgG antibodies to ARAQV, which represents an overall seroprevalence of 17%. Five of these bats were from São Paulo state and four were from Minas Gerais state. Of these, five were frugivorous, one was carnivorous, and three were sanguivorous (Family Species Captured Infected/tested Main feeding items Phyllostomidae Artibeus lituratus 41 1/6 Fruits Phyllostomidae A. obscurus 2 1/2 Fruits Phyllostomidae A. planirostris 41 1/3 Fruits Phyllostomidae Carollia perspicillata 43 1/10 Fruits and insects Phyllostomidae Chiroderma villosum 1 1/1 Fruits Phyllostomidae Chrotopterus auritus 1 1/1 Small vertebrates Phyllostomidae Desmodus rotundus 11 3/5 Mammals blood Phyllostomidae Glossophaga soricina 22 0/5 Nectar and pollen Phyllostomidae Lonchophylla spp. 1 0/1 Nectar and pollen Phyllostomidae Micronycteris minuta 1 0/1 Insects Molossidae Molossops neglectus 1 0/1 Insects Molossidae Molossops temminckii 2 0/1 Insects Vespertilionidae Myotis nigricans 13 0/5 Insects Vespertilionidae Myotis albescens 4 0/1 Insects Phyllostomidae Platyrrhinus lineatus 23 0/4 Fruits Phyllostomidae Sturnira lilium 38 0/6 Fruits
Table 1
Trap sites general features6Trap sites/altitude (m) | City/state | Main vegetation | Secondary vegetation | Features | |
---|---|---|---|---|---|
1 | JES/600 | Luis Antonio/SP | Cerrado* | Semideciduous forest | Continuous Cerrado |
2 | NEF/775 | Cajuru/SP | Grassland | Cerrado | Monocultures |
3 | SGF/860 | Batatais/SP | Sugarcane | Cerrado | Monocultures |
4 | SEP/872 | Montes Claros/MG | Dry forest†7 | Cerrado | Karst topography |
5 | LGEP/1,009 | Montes Claros/MG | Cerrado8 | Gallery forest | Caves and shelters |