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1.
Philos Trans R Soc Lond B Biol Sci ; 378(1867): 20210081, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36373926

RESUMO

Many natural forests in Southeast Asia are degraded following decades of logging. Restoration of these forests is delayed by ongoing logging and tropical cyclones, but the implications for recovery are largely uncertain. We analysed meteorological, satellite and forest inventory plot data to assess the effect of Typhoon Doksuri, a major tropical cyclone, on the forest landscapes of central Vietnam consisting of natural forests and plantations. We estimated the return period for a cyclone of this intensity to be 40 years. Plantations were almost twice as likely to suffer cyclone damage compared to natural forests. Logged natural forests (9-12 years after cessation of government-licensed logging) were surveyed before and after the storm with 2 years between measurements and remained a small biomass carbon sink (0.1 ± 0.3 Mg C ha-1 yr-1) over this period. The cyclone reduced the carbon sink of recovering natural forests by an average of 0.85 Mg C ha-1 yr-1, less than the carbon loss due to ongoing unlicensed logging. Restoration of forest landscapes in Southeast Asia requires a reduction in unlicensed logging and prevention of further conversion of degraded natural forests to plantations, particularly in landscapes prone to tropical cyclones where natural forests provide a resilient carbon sink. This article is part of the theme issue 'Understanding forest landscape restoration: reinforcing scientific foundations for the UN Decade on Ecosystem Restoration'.


Assuntos
Tempestades Ciclônicas , Agricultura Florestal , Ecossistema , Vietnã , Florestas , Clima Tropical , Árvores , Conservação dos Recursos Naturais
2.
J Endocrinol Invest ; 45(8): 1483-1495, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35181849

RESUMO

The SARS-CoV-2 virus continues to overwhelm health care systems impairing human to human social and economic interactions. Invasion or damage to the male reproductive system is one of the documented outcomes of viral infection. Existing studies have reported that SARS-CoV-2 may contribute to this loss in relation to inflammatory responses and the formation of cytokine storms in COVID-19 patients. Although direct infection of the testes and entry of SARS-CoV-2 into semen as well as subsequent consequences on the male reproductive system need to be studied more systematically, warnings from two organising ASRM and SART for prospective parents when infected with SARS-CoV-2 should be considered. In the context of an increasingly complex pandemic, this review provides preliminary examples of the potential impact of COVID-19 on male reproductive health and guidance for prospective parents currently infected with or recovering from SARS-CoV-2.


Assuntos
COVID-19 , Humanos , Masculino , Pandemias , Estudos Prospectivos , Saúde Reprodutiva , SARS-CoV-2
3.
AJNR Am J Neuroradiol ; 41(9): 1740-1744, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32675339

RESUMO

Malignant epithelioid glioneuronal tumor is a rare high-grade, aggressive brain tumor that shows both glial and neuronal differentiation on histopathology but is not included in the current World Health Organization classification. The neuroimaging appearance is variable but may be secondary to the size of the mass and/or location of the tumor. In our series, all epithelioid glioneuronal tumors were encountered in the supratentorial space and included pineal, temporal, and extratemporal lobar cerebral hemisphere locations. When large, the tumors demonstrate cystic degeneration and necrosis, hemorrhage, contrast enhancement, and regions of low apparent diffusion coefficient scalars consistent with patterns seen with other high-grade pediatric brain tumors. The tumors also have a propensity to spread into the meninges at presentation and for distant CSF spread on follow-up imaging.


Assuntos
Ganglioglioma/diagnóstico por imagem , Ganglioglioma/patologia , Neuroimagem/métodos , Neoplasias Supratentoriais/diagnóstico por imagem , Neoplasias Supratentoriais/patologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino
4.
Proc Natl Acad Sci U S A ; 98(21): 11961-6, 2001 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-11593004

RESUMO

The myeloperoxidase system of neutrophils uses hydrogen peroxide and chloride to generate hypochlorous acid, a potent bactericidal oxidant in vitro. In a mouse model of polymicrobial sepsis, we observed that mice deficient in myeloperoxidase were more likely than wild-type mice to die from infection. Mass spectrometric analysis of peritoneal inflammatory fluid from septic wild-type mice detected elevated concentrations of 3-chlorotyrosine, a characteristic end product of the myeloperoxidase system. Levels of 3-chlorotyrosine did not rise in the septic myeloperoxidase-deficient mice. Thus, myeloperoxidase seems to protect against sepsis in vivo by producing halogenating species. Surprisingly, levels of 3-bromotyrosine also were elevated in peritoneal fluid from septic wild-type mice and were markedly reduced in peritoneal fluid from septic myeloperoxidase-deficient mice. Furthermore, physiologic concentrations of bromide modulated the bactericidal effects of myeloperoxidase in vitro. It seems, therefore, that myeloperoxidase can use bromide as well as chloride to produce oxidants in vivo, even though the extracellular concentration of bromide is at least 1,000-fold lower than that of chloride. Thus, myeloperoxidase plays an important role in host defense against bacterial pathogens, and bromide might be a previously unsuspected component of this system.


Assuntos
Infecções por Klebsiella/enzimologia , Klebsiella pneumoniae/patogenicidade , Neutrófilos/enzimologia , Oxidantes/metabolismo , Peroxidase/fisiologia , Sepse/enzimologia , Tirosina/análogos & derivados , Tirosina/metabolismo , Animais , Bromo/metabolismo , Cloro/metabolismo , Modelos Animais de Doenças , Células HL-60 , Humanos , Ácido Hipocloroso/metabolismo , Íons , Infecções por Klebsiella/metabolismo , Infecções por Klebsiella/mortalidade , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Peroxidase/genética , Peroxidase/metabolismo , Sepse/metabolismo , Sepse/mortalidade
5.
Nucl Med Commun ; 19(8): 771-5, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9751931

RESUMO

The aim of this study was to evaluate the accuracy of the 14C-urea breath test by comparing the results to those obtained by endoscopy with mucosal biopsy. We also examined the value of the breath test result obtained prior to endoscopy in predicting peptic ulcer disease. Forty-two individuals underwent the 14C-urea breath test. Collections of expired C02 were analysed using a liquid scintillation counter. All individuals then underwent endoscopy with biopsy. Biopsy material was evaluated by the rapid urease method and by histology for the presence of H. pylori. Our results demonstrated that the 14C-urea breath test was 100% sensitive and specific when compared to the rapid urease test as the 'gold standard' for the detection of H. pylori. In comparison to pathology, the sensitivity remained 100% and the specificity was 89%. The results of the 14C-urea breath test had a poor predictive value for the determination of peptic ulcer disease. We conclude that the 14C-urea breath test can be easily performed at any medical facility equipped with a liquid scintillation counter and can accurately detect H. pylori. A negative breath test result could not exclude the presence of peptic ulcer disease.


Assuntos
Testes Respiratórios/métodos , Radioisótopos de Carbono , Infecções por Helicobacter/diagnóstico , Helicobacter pylori , Ureia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Feminino , Gastroscopia , Infecções por Helicobacter/metabolismo , Infecções por Helicobacter/microbiologia , Helicobacter pylori/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Úlcera Péptica/diagnóstico , Úlcera Péptica/metabolismo , Úlcera Péptica/microbiologia , Sensibilidade e Especificidade , Ureia/administração & dosagem , Ureia/metabolismo
6.
J Nerv Ment Dis ; 183(12): 768-73, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8522939

RESUMO

This study was designed to determine the extent of family problems among a clinic population of Cambodian and Vietnamese refugees, and to identify similarities and differences between the two groups. All 107 patients with adolescent children from a total clinic population of 298 were interviewed using a semistructured questionnaire, results were tabulated, and statistical methods were applied. The types of problems with children described by parents were classified into the dimensions of communication, personal behaviors, school performance, social behaviors, and antisocial behaviors. There were significantly more problems described by Vietnamese parents as compared with Cambodian parents. Vietnamese parents reported significantly more dissatisfaction with life in the United States. For both ethnic groups, parents' relationships with their adolescent children were a major source of concern and had a major impact on parents' perceptions of their own health. Yet, there were important ethnic differences between these refugee groups in how patients perceived their problems.


Assuntos
Etnicidade/psicologia , Família , Transtornos Mentais/epidemiologia , Refugiados/psicologia , Aculturação , Adolescente , Adulto , Transtorno da Personalidade Antissocial/diagnóstico , Transtorno da Personalidade Antissocial/epidemiologia , Atitude Frente a Saúde , Camboja/etnologia , Criança , Comorbidade , Comparação Transcultural , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/epidemiologia , Características da Família , Feminino , Humanos , Masculino , Transtornos Mentais/diagnóstico , Relações Pais-Filho , Satisfação Pessoal , Prevalência , Fatores Sexuais , Pais Solteiros/psicologia , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Inquéritos e Questionários , Estados Unidos , Vietnã/etnologia
7.
J Nucl Med ; 35(7): 1167-9, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8014677

RESUMO

Sternal abnormalities in sickle-cell disease have been documented by bone scintigraphy and radiography in patients with homozygous sickle-cell anemia, but not in patients with sickle-thalassemia. We present here two unusual cases of sternal abnormalities in complicated sickle-cell disease. One is an infant with radiographic findings of "sternal cupping" and transient hypo-ossification of the sternum and sickle-thalassemia. The other patient is also a male infant with unusual, persistent under-ossification of bone, in association with radiographic findings of "sternal cupping." The second patient also had a 4P-chromosomal defect (Wolf-Hirschhorn syndrome) in which sternal hypo-ossification was described.


Assuntos
Anemia Falciforme/diagnóstico por imagem , Esterno/diagnóstico por imagem , Anormalidades Múltiplas/diagnóstico por imagem , Humanos , Lactente , Masculino , Cintilografia , Síndrome , Talassemia/diagnóstico por imagem
8.
Clin Nucl Med ; 19(4): 307-8, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8004861

RESUMO

A case of unilateral tibial osteomyelitis in a 20-month-old child after bilateral intraosseous infusion (IOI) needle placement is presented. A review of the indications, potential complications, and scan findings is discussed. This case also shows the lack of significant uptake in the noninfected side, suggesting that a three-phase bone scan is of value in differentiating reactive bone from infected bone in patients with IOI.


Assuntos
Infusões Intraósseas/efeitos adversos , Osteomielite/diagnóstico por imagem , Osteomielite/etiologia , Tíbia/diagnóstico por imagem , Feminino , Humanos , Lactente , Cintilografia , Choque Séptico/tratamento farmacológico , Medronato de Tecnécio Tc 99m
9.
Stroke ; 24(9): 1322-9, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8362425

RESUMO

BACKGROUND AND PURPOSE: New therapeutic interventions for acute ischemic stroke are aimed at improving cerebral blood flow in the first 3 to 6 hours after symptom onset. Single-photon emission-computed tomography (SPECT) performed in the setting of clinical therapeutic trials may give us a better understanding of the physiological response to new forms of treatment and could impact acute management decisions. METHODS: We prospectively studied 15 patients with hemispheric ischemic stroke with SPECT within 6 hours of symptom onset and again at 24 hours. The ischemic defect was assessed in a semiquantitative manner that used computer-generated regions of interest (SPECT graded scale). This measure was correlated with clinical presentation (National Institutes of Health [NIH] Stroke Scale), initial clinical course (change in NIH Stroke Scale), long-term outcome (Barthel Index at 3 months), and complications of cerebral hemorrhage and edema. RESULTS: The severity of the SPECT graded scale on the admission scan correlated with the severity of neurological deficit (admission NIH Stroke Scale) (P < .05) and was positively associated with poor long-term outcome as measured with the Barthel Index (P < .001) and the complications of cerebral hemorrhage and massive cerebral edema (P < .005). In fact, there was a threshold value for the SPECT graded scale above which all patients suffered poor long-term outcome and the complications of cerebral hemorrhage and edema. CONCLUSIONS: The measurement of an ischemic defect using SPECT is a valid assessment of hemispheric stroke severity in the hyperacute setting and may be useful for selecting or stratifying patients in clinical therapeutic trials.


Assuntos
Transtornos Cerebrovasculares/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Edema Encefálico/etiologia , Hemorragia Cerebral/etiologia , Transtornos Cerebrovasculares/complicações , Transtornos Cerebrovasculares/diagnóstico , Transtornos Cerebrovasculares/terapia , Feminino , Humanos , Ataque Isquêmico Transitório/diagnóstico , Ataque Isquêmico Transitório/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , National Institutes of Health (U.S.) , Estados Unidos
10.
Arch Neurol ; 50(8): 855-62, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8352673

RESUMO

OBJECTIVE: To determine if previously hypertensive patients with acute ischemic stroke should be treated with antihypertensive medication in the immediate poststroke period. DESIGN: Randomized double-blind, placebo-controlled trial. SETTING: Sixteen consecutive hypertensive patients (four men and 12 women; mean age, 66 years [age range, 46 to 83 years]) with middle cerebral artery infarction within 72 hours of onset and blood pressure between 170 and 220 mm Hg(systolic) and 95 and 120 mm Hg (diastolic). INTERVENTION: Placebo (n = 6), nicardipine hydrochloride (20 mg [n = 5]), captopril (12.5 mg [n = 3]), or clonidine hydrochloride (0.1 mg [n = 2]) given every 8 hours for 3 days. MAIN OUTCOME MEASURES: Decline in blood pressure, change in cerebral blood flow as measured by single photon emission computed tomography, and clinical change as determined by the National Institutes of Health Stroke Scale. RESULTS: Blood pressure fell significantly in both the drug-treated group as a whole and in those patients receiving placebo (P < .001). There was no difference in blood pressure levels between these two groups throughout the study period. Patients receiving nicardipine had a consistently lower pressure than the other groups. A significant negative relationship was noted between the maximum blood pressure fall and improvement in cerebral blood flow. There were four patients whose blood pressure dropped by more than 16% of the baseline value on any 24 hours in the first 3 days. All either failed to increase or actually decreased their cerebral blood flow to the affected area. Three of these patients were treated with nicardipine. There was no significant difference in clinical course between the placebo-and drug-treated groups as a whole. CONCLUSIONS: Hypertensive ischemic stroke patients with a moderate elevation of blood pressure in the first few days may not require antihypertensive therapy. Nicardipine and possibly other calcium channel blockers may cause an excessive fall in blood pressure and impair cerebral blood flow in these patients and should therefore be used with caution.


Assuntos
Encéfalo/diagnóstico por imagem , Transtornos Cerebrovasculares/etiologia , Hipertensão/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Circulação Cerebrovascular/efeitos dos fármacos , Circulação Cerebrovascular/fisiologia , Método Duplo-Cego , Feminino , Humanos , Hipertensão/complicações , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada de Emissão de Fóton Único
11.
Clin Nucl Med ; 16(1): 1-3, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1999048

RESUMO

The rim sign of increased activity in the gallbladder fossa during nuclear hepatobiliary imaging has been described, with one exception, only in conjunction with a nonvisualizing gallbladder, and it strongly suggests acute complicated cholecystitis. A case is presented in which a rim sign was present despite later visualization of the gallbladder in presumed chronic cholecystitis.


Assuntos
Colecistite/diagnóstico por imagem , Vesícula Biliar/diagnóstico por imagem , Adulto , Doença Crônica , Feminino , Humanos , Iminoácidos , Compostos de Organotecnécio , Cintilografia , Disofenina Tecnécio Tc 99m , Fatores de Tempo
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