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1.
An Acad Bras Cienc ; 95(1): e20201503, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37222358

RESUMO

Quantitative data obtained from native forests is costly and time-consuming. Thus, alternative measurement methods need to be developed to provide reliable information, especially in Atlantic Rain Forests. In this study we evaluated the hypothesis that the combination of an Airborne Laser Scanner (ALS) and an Unmanned Aerial Vehicle (UAV) can provide accurate quantitative information on tree height, volume, and aboveground biomass of the Araucaria angustifolia species. The study was carried out in Atlantic Rain forest fragments in southern Brazil. We tested and evaluated 3 digital canopy height model (CHM) scenarios: 1) CHM derived from ALS models; 2) CHM derived from UAV models; and 3) CHM from a combined ALS digital terrain model and UAV digital surface model. The height value at each tree coordinate was extracted from the pixel in the three evaluated scenarios and compared with the field measured values. ALS and UAV+ALS obtained RMSE% of 6.38 and 12.82 for height estimates, while UAV was 49.91%. Volume and aboveground biomass predictions are more accurate by ALS and UAV+ALS, while the UAV produced biased estimates. Since the ALS is currently used, periodic monitoring can be carried out by a combination of active (ALS) and passive (UAV) sensors.


Assuntos
Araucaria , Monitorização de Parâmetros Ecológicos , Biomassa , Lasers , Árvores , Dispositivos Aéreos não Tripulados , Monitorização de Parâmetros Ecológicos/instrumentação , Monitorização de Parâmetros Ecológicos/métodos
2.
Neuropharmacology ; 57(3): 332-42, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19481555

RESUMO

Several cytisine derivatives have been developed in the search for more selective drugs at nicotinic acetylcholine receptors (nAChR). Binding experiments in transfected cell lines showed that the iodination of cytisine in the position 3 of the pyridone ring increased potency at alpha7-nAChR and to a lesser extent at the alpha4beta2 subtypes, both of which are widely expressed in the brain. However, no in vivo studies have been published on this compound. Inhibition curves presented here using wild type, beta2, and beta4-null mutant mice confirm that 3-IC binds to alpha4beta2 *, alpha7 * and alpha3beta4 * receptors with higher affinity than cytisine (asterisk indicates the receptor may contain additional subunits, Lukas et al., 1999). Intraperitoneal injection of 3-iodocytisine (3-IC) induced considerable dose-dependent hypothermia in DBA/2J and C57BL/6J mice. This response was blocked by mecamylamine and partially inhibited by hexamethonium. beta4-null mice displayed significantly less 3-IC-induced hypothermia than wild-type mice, beta2-null mice were somewhat less affected than wild types, while responses of alpha7 *-null mice were similar to wild types. Mice treated chronically with 3-IC display a marked increase in alpha7 * and alpha4beta2 * binding sites determined by radioligand binding in membrane preparations from cerebral cortex and hippocampus. Quantitative autoradiographic analysis of 28 brain regions of mice treated with 3-IC was consistent with the membrane binding, detecting an increase of cytisine-sensitive [(125)I]epibatidine binding sites, while cytisine-resistant [(125)I]epibatidine sites were unchanged. [(125)I]alpha-Bungarotoxin binding sites also exhibited up-regulation. These results give a first evaluation of in vivo consequences of 3-IC as a potent agonist with marked effects on mice.


Assuntos
Alcaloides/farmacologia , Azocinas/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Hipotermia/induzido quimicamente , Quinolizinas/farmacologia , Receptores Nicotínicos/metabolismo , Animais , Sítios de Ligação , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Relação Dose-Resposta a Droga , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipotermia/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Knockout , Distribuição Aleatória , Receptores Nicotínicos/genética , Receptor Nicotínico de Acetilcolina alfa7
3.
J Pediatr ; 134(4): 413-21, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10190914

RESUMO

UNLABELLED: We determined whether a beta-lactam and an aminoglycoside have efficacy greater than a beta-lactam alone in the management of a pulmonary exacerbation in patients with cystic fibrosis. STUDY DESIGN: Azlocillin and placebo or azlocillin and tobramycin were administered to 76 patients with a pulmonary exacerbation caused by Pseudomonas aeruginosa in a randomized double-blind, third-party monitored protocol. Improvement was assessed by standardized clinical evaluation, pulmonary function testing, sputum bacterial density, sputum DNA content, and time to the next pulmonary exacerbation requiring hospitalization. RESULTS: No significant difference was seen between the 2 treatment groups in clinical evaluation, sputum DNA concentration, forced vital capacity, forced expiratory volume in second 1, or peak expiratory flow rate at the end of treatment (33 receiving azlocillin alone and 43 both antibiotics); adverse reactions were equivalent in each group. Sputum P. aeruginosa density decreased more with combination therapy (P =.034). On follow-up evaluation, an average of 26 days after the end of treatment, all outcome indicators had worsened in both groups. Time to readmission for a new pulmonary exacerbation was significantly longer in the group receiving azlocillin plus tobramycin (P <.001). Treatment-emergent tobramycin resistance occurred in both groups and was more frequent with combination therapy. CONCLUSION: We conclude that the combination of a beta-lactam and an aminoglycoside produces a longer clinical remission than a beta-lactam alone and slightly better initial improvement.


Assuntos
Antibacterianos/uso terapêutico , Azlocilina/uso terapêutico , Fibrose Cística/tratamento farmacológico , Quimioterapia Combinada/uso terapêutico , Penicilinas/uso terapêutico , Tobramicina/uso terapêutico , Adolescente , Análise de Variância , Antibacterianos/efeitos adversos , Azlocilina/efeitos adversos , Criança , DNA Bacteriano/efeitos dos fármacos , DNA Bacteriano/isolamento & purificação , Método Duplo-Cego , Feminino , Humanos , Injeções Intravenosas , Masculino , Penicilinas/efeitos adversos , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Testes de Função Respiratória , Escarro/efeitos dos fármacos , Escarro/microbiologia , Tobramicina/efeitos adversos , Capacidade Vital/efeitos dos fármacos
4.
J Pediatr ; 125(2): 304-7, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8040782

RESUMO

Computed tomography scans of the head and early neurodevelopmental assessment (Bayley Scales of Infant development) were recorded for 24 surviving infants who received venovenous extracorporeal membrane oxygenation and were compared with those of infants treated with venoarterial bypass matched by diagnosis and oxygenation index before extracorporeal membrane oxygenation. A comparable neuroradiographic and early neurodevelopmental outcome was documented for survivors of venoarterial and venovenous extracorporeal membrane oxygenation.


Assuntos
Encéfalo/diagnóstico por imagem , Desenvolvimento Infantil , Oxigenação por Membrana Extracorpórea/métodos , Seguimentos , Humanos , Lactente , Veias Jugulares , Insuficiência Respiratória/terapia , Sobreviventes , Tomografia Computadorizada por Raios X
6.
J Pediatr ; 121(1): 75-8, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1625097

RESUMO

Studies from Africa suggest that vitamin A supplementation may reduce morbidity and mortality rates associated with measles among poorly nourished children. We studied 20 children with measles in Long Beach, Calif., and found that 50% (95% confidence interval; 28% to 72%) were vitamin A deficient. This frequency among presumably well nourished American children supports evaluation of vitamin A status as a part of acute management of measles in the United States.


Assuntos
Sarampo/sangue , Vitamina A/sangue , California , Pré-Escolar , Feminino , Humanos , Lactente , Infecções , Masculino , Sarampo/complicações , Projetos Piloto , Pré-Albumina/análise , Pré-Albumina/deficiência , Proteínas de Ligação ao Retinol/análise , Proteínas de Ligação ao Retinol/deficiência , Deficiência de Vitamina A/sangue , Deficiência de Vitamina A/complicações
8.
J Pediatr ; 112(4): 547-54, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3127569

RESUMO

We sought to define objective indicators of the resolution of Pseudomonas aeruginosa endobronchial infection in patients with cystic fibrosis. We prospectively studied 75 patients admitted for treatment of a pulmonary exacerbation and quantitated sputum bacterial density, DNA content, and the concentration of albumin and total protein in sputum, and compared these values with clinical evaluation. Eleven of the 75 patients had systemic signs, fever, and leukocytosis, which we arbitrarily defined as due to endobronchial infection. At the end of hospitalization, these 11 patients were afebrile, had peripheral leukocyte counts in the normal range, and were judged improved. Sputum P. aeruginosa density, DNA content, and total protein content on admission were similar in the two illness groups. Hospitalization and parenteral antibiotic administration for an average of 14.6 days were associated with improved pulmonary function in all 75 subjects (P values for forced vital capacity, forced expiratory volume at 1 second, and peak expiratory flow rate were all less than 0.001). With improvement, there was a decrease in sputum P. aeruginosa density (mean of both groups decreased from 10(7.80) CFU/g on admission to 10(5.96) CFU/g; P less than 0.001), and a decreased DNA concentration (overall mean 4.73 +/- 4.75 on admission to 2.76 +/- 2.49 mg/g; P less than 0.002). The decrease in sputum total protein concentration for both groups was not significant (overall mean 60.5 +/- 48.4 to 43.9 +/- 38.2 mg/g; P = 0.06). Sputum albumin concentrations did not change in either group. We conclude that in cystic fibrosis subjects with a pulmonary exacerbation, bacterial density, sputum DNA and protein content decrease with hospitalization and parenteral antibiotic therapy. At the end of treatment, these indices of sputum infection and inflammation correlate with improved pulmonary function and clinical improvement. These changes are independent of the presence or absence of fever on admission.


Assuntos
Fibrose Cística/complicações , Infecções por Pseudomonas/diagnóstico , Infecções Respiratórias/diagnóstico , Escarro/análise , Adolescente , Adulto , Albuminas/análise , Antibacterianos/uso terapêutico , Criança , DNA/análise , Hospitalização , Humanos , Proteínas/análise , Infecções por Pseudomonas/complicações , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/análise , Testes de Função Respiratória , Infecções Respiratórias/complicações , Infecções Respiratórias/tratamento farmacológico
14.
J Pediatr ; 109(1): 123-30, 1986 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3522832

RESUMO

In a multicenter randomized trial, 107 children with bacterial meningitis were initially given either cefuroxime or ampicillin plus chloramphenicol. Patients were alternately assigned to 7- or 10-day courses of the designated antimicrobial regimen. CSF isolates included Haemophilus influenzae type b (89, of which 25% were beta-lactamase positive), Streptococcus pneumoniae, and Neisseria meningitidis. Although mean CSF bactericidal titers against Haemophilus isolates were 1:6 in each treatment group, H. influenzae was cultured from CSF in four of 39 patients receiving cefuroxime, 24 to 48 hours after initiation of therapy, compared with none of 40 patients given ampicillin plus chloramphenicol (P = 0.11). Clinical cure rates were similar (95%); one death occurred in each group. One child given cefuroxime had persistent meningitis after 5 days of therapy, and mastoiditis with secondary bacteremia developed in one on day 10. Three patients had relapse or reinfection. One patient who received cefuroxime for 10 days had a relapse of epiglottitis 17 days later, and of the patients given ampicillin plus chloramphenicol, one had a relapse of meningitis 1 week after 7 days of therapy, and bacteremia developed in one 42 days after completion of 10 days of therapy. No increase in either in-hospital complications or relapses occurred with a 7-day treatment course. Proof of the equivalence of the antibiotic regimens and the efficacy of 7-day courses of treatment, as well as the consequences of delayed CSF sterilization, will require additional investigation.


Assuntos
Ampicilina/administração & dosagem , Infecções Bacterianas/tratamento farmacológico , Cefuroxima/uso terapêutico , Cefalosporinas/uso terapêutico , Cloranfenicol/administração & dosagem , Meningite/tratamento farmacológico , Adolescente , Ampicilina/uso terapêutico , Infecções Bacterianas/complicações , Infecções Bacterianas/diagnóstico , Criança , Pré-Escolar , Cloranfenicol/uso terapêutico , Ensaios Clínicos como Assunto , Quimioterapia Combinada , Feminino , Humanos , Lactente , Masculino , Meningite/complicações , Meningite/diagnóstico , Meningite por Haemophilus/tratamento farmacológico , Meningite Meningocócica/tratamento farmacológico , Meningite Pneumocócica/tratamento farmacológico , Distribuição Aleatória
19.
J Pediatr ; 104(3): 454-9, 1984 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6608581

RESUMO

Thirty-four children with Haemophilus influenzae type b meningitis were given prospectively either moxalactam (200 mg/kg/day) or ampicillin (400 mg/kg/day) plus chloramphenicol (75 mg/kg/day). One patient in each group died. The mean duration of fever, clinical response, sequential cerebrospinal fluid findings, and incidence of neurologic sequelae were similar between groups. Moxalactam cerebrospinal fluid bioactivity was significantly greater than that of ampicillin or chloramphenicol throughout therapy. Neutropenia, liver enzyme abnormalities, and diarrhea were not significantly different. In eight of 11 patients given moxalactam (versus one of 14 controls) there was complete elimination of gram-negative aerobic flora in the stools by day 10 (P = 0.002); however, none acquired Clostridium difficile. Moxalactam in effective therapy for H. influenzae type b meningitis.


Assuntos
Meningite por Haemophilus/tratamento farmacológico , Moxalactam/administração & dosagem , Ampicilina/administração & dosagem , Ampicilina/efeitos adversos , Disponibilidade Biológica , Pré-Escolar , Cloranfenicol/administração & dosagem , Cloranfenicol/efeitos adversos , Quimioterapia Combinada , Feminino , Haemophilus influenzae/efeitos dos fármacos , Humanos , Lactente , Cinética , Masculino , Meningite por Haemophilus/sangue , Meningite por Haemophilus/líquido cefalorraquidiano , Moxalactam/efeitos adversos , Moxalactam/sangue , Estudos Prospectivos
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