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991.
Brand GD Leite JR de Sá Mandel SM Mesquita DA Silva LP Prates MV Barbosa EA Vinecky F Martins GR Galasso JH Kuckelhaus SA Sampaio RN Furtado JR Andrade AC Bloch C 《Biochemical and biophysical research communications》2006,347(3):739-746
Six new antimicrobial peptides structurally related to the dermaseptin family have been isolated from the skin secretion of the amphibian Phyllomedusa hypochondrialis. The primary structures of these molecules named as DShypo 01, 02, 03, 04, 06, and 07 were determined by de novo MS/MS experiments, Edman degradation, and cDNA sequencing. The fifth peptide was found to be precisely the same DS 01 from Phyllomedusa oreades previously described by our group. The majority of the peptides purified from the crude skin secretion could be directly localized and mapped onto a freshly dissected dorsal skin fragment using mass spectrometry-imaging techniques. Comparisons between peptides and commercial drugs on their antibacterial and anti-Leishmania amazonensis efficiencies, associated with peptide lytic effects on mammalian blood cells and surface plasmon resonance interaction studies on immobilized DMPC vesicles, were also performed. 相似文献
992.
W J Vallins N J Brand N Dabhade G Butler-Browne M H Yacoub P J Barton 《FEBS letters》1990,270(1-2):57-61
We have used the polymerase chain reaction (PCR) to synthesise a cDNA encoding part of human cardiac troponin I. Amplification was achieved using fully degenerate sets of oligonucleotides corresponding to conserved regions of amino acid sequence identified in other troponin I isoforms. The cloned PCR fragment was subsequently used to isolate full-length cDNAs from a cardiac cDNA library. We describe the approach, as a general cloning strategy starting from limited amino-acid sequence data and report the cloning, and complete amino acid sequence of human cardiac troponin I. Analysis of human development using these clones demonstrates early expression of this gene in the heart. 相似文献
993.
Carlos Martins Luís F. Azevedo Orquídea Ribeiro Luísa Sá Paulo Santos Luciana Couto Altamiro Costa-Pereira Alberto P. Hespanhol 《PloS one》2013,8(11)
Background
Most of the strategies to induce a more rational use of preventive health services are oriented to the medical side of the doctor-patient relationship. However, the consultation model has changed, and patients now have a more important role in medical consultation. The aim of this study was to assess which healthcare services are deemed necessary, and with what frequency, by adults from the general Portuguese population.Methods
Design: Population-based nationwide cross-sectional study Setting: Portuguese population Participants: One thousand Portuguese adults, surveyed by computer-assisted telephone interviewing and selected by a stratified cluster sampling design. Measurements: Proportions and population prevalence estimates were determined for each healthcare service, taking into account whether respondents considered them necessary, and with what frequency.Results
Respondent ages ranged between 18 and 97 years, and 520 of 1000 (52%) respondents were women. Among Portuguese adults, 99.2% (95% confidence interval (CI): 98.5 to 99.6) believe that they should undergo general routine blood and urine tests, to be repeated every 12.0 months on average (95% CI: 11.4 to 12.6); 87.4% (95% CI: 85.3 to 89.3) of the respondents reported having actually performed these tests. Of the 15 services surveyed, 14 were considered periodically necessary by more than 60% of respondents. Among the respondents, 37.7% (95% CI: 34.5 to 41.1) reported using healthcare services by their own initiative.Conclusions
The majority of Portuguese adults believe that they should utilize a great number of healthcare services, on a nearly annual basis; most actually follow this schedule. Our findings indicate a tendency towards the overuse of resources.Adequate patient-oriented strategies regarding the use of medical tests and preventive interventions—with appropriate information and discussion of risks and harms—are urgently needed, and crucial for achieving a more rational use of healthcare services and for preventing the consequences of over-testing. 相似文献994.
José Brandão-Neto Carlos A. Bruno da Silva Nancy Bueno Figueiredo Tadao Shuhama Nara Fabiana da Cunha Fernanda Barral Dias Dourado Luciana Ansaneli Naves 《Biometals》1999,12(2):161-166
Acute or chronic zinc administration may cause hyperglycemia in experimental animals. These findings are attributed to permissive actions of glucocorticoids and glucagon upon hepatic gluconeogenesis and glycogenolysis. The effect of Zn++ on plasma glucose, C-peptide, glucagon, and cortisol was investigated in healthy and insulin-dependent diabetes mellitus (IDDM) patients. Ten normal individuals (5 of each sex, aged 24.10 ± 1.96) and 10 IDDM (5 of each sex, aged 25.20 ± 8.10) were tested at 7:00 AM after 12-h fast. Twenty-five mg of Zn++ were administered intravenously during 1 min, and blood samples were collected from the contralateral arm at 0, 3, 30, 60, 90 and 120 min after Zn++ injection. The plasma levels of glucose, C-peptide, and glucagon remained constant throughout the experimental period in both groups studied. Plasma cortisol levels decreased significantly, which is consistent with our previous findings. These results suggest that, in contrast to experimental animals, acute Zn++ administration, despite decreasing cortisol levels, does not change carbohydrate metabolism in human beings. 相似文献
995.
996.
Liliane Maria Vidal Siqueira Luciana Inácia Gomes Edward Oliveira Eduardo Ribeiro de Oliveira áureo Almeida de Oliveira Martin Johannes Enk Nídia Figueiredo Carneiro Ana Rabello Paulo Marcos Zech Coelho 《Memórias do Instituto Oswaldo Cruz》2015,110(2):209-214
This study evaluated parasitological and molecular techniques for the diagnosis and
assessment of cure of schistosomiasis mansoni. A population-based study was performed
in 201 inhabitants from a low transmission locality named Pedra Preta, municipality
of Montes Claros, state of Minas Gerais, Brazil. Four stool samples were analysed
using two techniques, the Kato-Katz® (KK) technique (18 slides) and the
TF-Test®, to establish the infection rate. The positivity rate of 18 KK
slides of four stool samples was 28.9% (58/201) and the combined parasitological
techniques (KK+TF-Test®) produced a 35.8% positivity rate (72/201).
Furthermore, a polymerase chain reaction (PCR)-ELISA assay produced a positivity rate
of 23.4% (47/201) using the first sample. All 72 patients with positive
parasitological exams were treated with a single dose of Praziquantel® and
these patients were followed-up 30, 90 and 180 days after treatment to establish the
cure rate. Cure rates obtained by the analysis of 12 KK slides were 100%, 100% and
98.4% at 30, 90 and 180 days after treatment, respectively. PCR-ELISA revealed cure
rates of 98.5%, 95.5% and 96.5%, respectively. The diagnostic and assessment of cure
for schistosomiasis may require an increased number of KK slides or a test with
higher sensitivity, such as PCR-ELISA, in situations of very low parasite load, such
as after therapeutic interventions. 相似文献
997.
Gouveia TL Frangiotti MI de Brito JM de Castro Neto EF Sakata MM Febba AC Casarini DE Amado D Cavalheiro EA Almeida SS Manchini MT Araújo RC Silva JA Naffah-Mazzacoratti Mda G 《Neurochemistry international》2012,61(1):54-62
We previously showed that patients with temporal lobe epilepsy (TLE) present an increased expression of angiotensin II (AngII) AT1 and AT2 receptors in the hippocampus, supporting the idea of an upregulation of renin-angiotensin system (RAS) in this disease. This study aimed to verify the relationship between the RAS and TLE during epileptogenesis. Levels of the peptides angiotensin I (AngI), angiotensin II (AngII) and angiotensin 1-7 (Ang 1-7), were detected by HPLC assay. Angiotensin AT1 and AT2 receptors, Mas mRNA receptors and angiotensin converting enzyme (ACE), tonin and neutral endopeptidase (NEP) mRNA were also quantified at the hippocampus of Wistar rats by real time PCR, during acute (n=10), silent (n=10) and chronic (n=10) phases of pilocarpine-induced epilepsy. We observed an increased peptide level of Ang1-7 into acute and silent phases, decreasing importantly (p≤0.05) in the chronic phase, suggesting that AngI may be converted into Ang 1-7 by NEP, which is present in high levels in these periods. Our results also showed increased peptide level of AngII in the chronic phase of this model. In contraposition, the ACE expression is reduced in all periods. These data suggest that angiotensinogen or AngI may be cleaved to AngII by tonin, which showed increased expression in all phases. We found changes in AT1, AT2 and Mas mRNA receptors levels suggesting that Ang1-7 could act at Mas receptor during the silent period. Herein, we demonstrated for the first time, changes in angiotensin-related peptides, their receptors as well as the releasing enzymes in the hippocampus of rats during pilocarpine-induced epilepsy. 相似文献
998.
Clarissa Hamaio Okino-Delgado Milene Stefani Pereira João Vitor Inácio da Silva Daniela Kharfan Débora Zanoni do Prado Luciana Francisco Fleuri 《Biotechnology progress》2019,35(1):e2734
Brazil is the world's leading orange supplier for juice production purposes. However, the production process generates high amount of wastes, which leads to disposal problems. Orange wastes can be used for lipases production, incorporating the biorefinery concept into juice industries. Thus, the aim of the present study was to investigate the wastes of orange production chain as source of lipases based on different varieties (Pera, Hamlin, Valencia, and Natal), as well as on different fractions of wastes. The mass balance of the juice/wastes (2007–2016 crops) was evaluated, and lipases from different varieties and fraction were biochemically characterized. Overall, the wastes corresponded to approximately 43% of the fruit mass. All the fractions of all varieties showed lipase activity in emulsified olive oil and in p-nitrophenyl substrates. The highest lipase activities were obtained by Natal pulp in emulsified olive oil, Natal frit, and Hamlin peel in p-NPB and Hamlin frit in p-NPL and p-NPP. The bagasse, peel, and frit lipases from the different orange varieties showed optimum pH from 6.0 to 8.0 and optimal temperature from 30 °C to 60 °C. Thus, it is possible concluding that the orange processing for juice production purposes generates a large amount of wastes, which can be destined to profitable purposes as lipases production. Lipases produced by different fractions and varieties are biochemically diverse, enabling the application a wide range of processes. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2734, 2019 相似文献
999.
Toward an identification of mechanical parameters initiating periosteal remodeling: a combined experimental and analytic approach 总被引:2,自引:1,他引:2
The ability of bone to adapt to its mechanical environment is well recognized, although the specific mechanical parameters initiating or maintaining the adaptive responses have yet to be identified. Recently introduced mathematical models offer the potential to aid in the identification of such parameters, although these models have not been well validated experimentally or clinically. We formulated a complementary experimental/analytic approach, using an animal model with a well-controlled mechanical environment combined with finite element modeling (FEM). We selected the functionally isolated turkey ulna, since the loading could be completely characterized and the periosteal adaptive responses subsequently monitored and quantified after four and eight weeks of loading. Known loads input into a three-dimensional, linearly elastic FEM of the ulna then permitted full-field mechanical characterization of the ulna. The FEM was validated against a normal strain-gaged turkey ulna, loaded in vivo in an identical fashion to the experimental ulnae. Twenty-four candidate mechanical parameters were then compared to the quantified adaptive responses, using statistical techniques. The data supported strain energy density, longitudinal shear stress, and tensile principal stress/strain as the mechanical parameters most likely related to the initiation of the remodeling response. Model predictions can now suggest new experiments, against which the predictions can be supported or falsified. 相似文献
1000.
Claudio R. Simon Livia M.R. Moda Shirlei Octacilio‐Silva Lucas Anhezini Luciana C.H. Machado‐Gitai Ricardo Guelerman P. Ramos 《Genesis (New York, N.Y. : 2000)》2009,47(7):492-504
The Drosophila roughest (rst) locus encodes an immunoglobulin superfamily transmembrane glycoprotein implicated in a variety of embryonic and postembryonic developmental processes. Here we demonstrate a previously unnoticed role for this gene in the autophagic elimination of larval salivary glands during early pupal stages by showing that overexpression of the Rst protein ectodomain in early pupa leads to persistence of salivary glands up to at least 12 hours after head eversion, although with variable penetrance. The same phenotype is observed in individuals carrying the dominant regulatory allele rstD, but not in loss of function alleles. Analysis of persistent glands at the ultrastructural level showed that programmed cell death starts at the right time but is arrested at an early stage of the process. Finally we describe the expression pattern and intracellular distribution of Rst in wild type and rstD mutants, showing that its downregulation in salivary glands at the beginning of pupal stage is an important factor in the correct implementation of the autophagic program of this tissue in space and time. genesis 47:492–504, 2009. © 2009 Wiley‐Liss, Inc. 相似文献