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1.
Clin Exp Rheumatol ; 25(1 Suppl 44): S34-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17428362

RESUMO

A patient with atypical presentation of polymyalgia rheumatica is presented. Her major symptoms were mild weakness, pain on passive movement of the shoulder and hip girdles, with mild tenderness but no joint stiffness. Muscle enzymes were within the normal range. The diagnostic work-up included gallium-67 scintigraphy, which showed intense uptake in both shoulders, with remarkable improvement following steroid treatment. A prospective study may delineate the possible role of this imaging modality in establishing a diagnosis of polymyalgia rheumatica.


Assuntos
Bursite/diagnóstico por imagem , Radioisótopos de Gálio , Músculo Esquelético/diagnóstico por imagem , Polimialgia Reumática/diagnóstico por imagem , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão/métodos , Idoso , Bursite/tratamento farmacológico , Bursite/patologia , Feminino , Radioisótopos de Gálio/farmacocinética , Humanos , Polimialgia Reumática/tratamento farmacológico , Polimialgia Reumática/patologia , Prednisona/uso terapêutico , Resultado do Tratamento
2.
Cell Mol Biol (Noisy-le-grand) ; 50(5): 591-604, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15559976

RESUMO

Endolithic microbial communities inhabiting porous rocks in the cold, dry mountainous regions of Antarctica have been studied extensively as examples of life's adaptations to extreme environments. Here, we examine hydrocarbons and fatty acids occurring in these communities in order to clarify their biogeochemical features with respect to source organisms, microbial activity, fossilization processes and the influence of Gondwanaland sediments. Unusually, long-chain (>C19) n-alkanes and anteiso-alkanes were often the major hydrocarbons in the samples. A suite of n-alkanoic acids (n-C9-n-C32) and long-chain anteiso-alkanoic acids (a-C20-a-C30) were found, along with short-chain iso- and anteiso-alkanoic acids, and n-alkenoic acids. The relationship between long-chain n-alkanoic acids (n-C20-n-C32) and long-chain anteiso-alkanoic acids suggests that these compounds probably originated from the same group of microorganisms, such as bacteria or endolithic lichens, under moderate pH conditions (pH 3-5). Relatively high trans/cis-C16:1 alkenoic acid ratios suggest the presence of unfavorable environmental conditions in the endolithic microbial habitat. Normal-alkenoic/alkanoic acid ratios may be a useful marker for the fossilization of endolithic microbial communities. Thermally matured triterpanes and steranes from fossilized associations on Mount Fleming strongly suggest the presence of Gondwanaland sediments formed during Devonian and Jurassic (400-180 million years ago).


Assuntos
Bactérias/metabolismo , Eucariotos/metabolismo , Líquens/metabolismo , Metabolismo dos Lipídeos , Alcanos/metabolismo , Regiões Antárticas , Ácidos Graxos/metabolismo , Terpenos/metabolismo , Triterpenos/metabolismo
3.
Stud Health Technol Inform ; 84(Pt 1): 810-4, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11604847

RESUMO

National Asthma Education and Prevention Program (NAEPP) suggests using asthma action plans for patient self-care. Recent studies reported that many asthma patients had difficulties in following action plans on a daily basis and had low compliance to medication regimens. The goal of our study was to design and evaluate the Home Asthma Telemonitoring (HAT) system aimed to help asthma patients to follow their self-care plans according to the NAEPP recommendations. Our study resulted in the development of the system which provided patients with continuous individualized help in the daily routine of asthma self-care and notified heath care providers if certain clinical conditions occurred. This allowed early recognition of potentially dangerous situations and timely intervention. The evaluation of the HAT system underwent several stages. First we showed, that the HAT system provides reliable reciprocal exchange of all relevant information between a physician and asthma patient in home settings. Further evaluation demonstrated that lung function test results collected during home asthma telemonitoring are comparable to those collected under the supervision of trained professionals, and Internet-based home asthma telemonitoring can be successfully implemented in a group of patients without previous computer experience. Preliminary results of an on-going HAT evaluation showed higher patient compliance to asthma action plans in comparison to the compliance reported for patients in standard care. The clinical impact of HAT on asthma outcomes is being currently evaluated in a randomized clinical trial funded by NIH. HAT has a potential for improving clinical outcomes and quality of life in the studied patient population and may be a model for monitoring and self-management of patients with other chronic health conditions.


Assuntos
Asma/terapia , Autocuidado/métodos , Telemedicina , Asma/enfermagem , Sistemas de Apoio a Decisões Clínicas , Assistência Domiciliar , Humanos , Microcomputadores , Espirometria
4.
Clin Nutr ; 20(6): 535-40, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11884002

RESUMO

OBJECTIVE: To compare the indications for and the outcome of long-term enteral feeding by nasogastric tube (NGT) with that of percutaneous endoscopic gastrostomy (PEG) tube. DESIGN: A prospective, multicenter cohort study. SETTING: Acute geriatric units and long-term care (LTC) hospitals in Jerusalem, Israel. PARTICIPANTS: 122 chronic patients aged 65 years and older for whom long-term enteral feeding was indicated as determined by the treating physician. Patients with acute medical conditions at the time of tube placement were excluded. MEASUREMENTS: We examined the indications for enteral feeding, nutritional status, outcome and complications in all subjects. Subjects were followed for a minimum period of six months. RESULTS: Although the PEG patients were older and had a higher incidence of dementia, there was an improved survival in those patients with PEG as compared to NGT (hazard ratio (HR)=0.41; 95% confidence interval (CI) 0.22-0.76; P=0.01). Also, the patients with PEG had a lower rate of aspiration (HR=0.48; 95% CI 0.26-0.89) and self-extubation (HR=0.17; 95% CI 0.05-0.58) than those with NGT. Apart from a significant improvement in the serum albumin level at the 4-week follow-up assessment in the patients with PEG compared to those with NGT (adjusted mean 3.35 compared to 3.08; F=4.982), nutritional status was otherwise similar in both groups. CONCLUSION: In long-term enteral feeding, in a selected group of non-acute patients, the use of PEG was associated with improved survival, was better tolerated by the patient and was associated with a lower incidence of aspiration. A randomized controlled study is needed to determine whether PEG is truly superior to NGT.


Assuntos
Nutrição Enteral/métodos , Intubação Gastrointestinal/métodos , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Endoscopia , Feminino , Gastrostomia , Humanos , Incidência , Intubação Gastrointestinal/efeitos adversos , Masculino , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento
5.
Appl Environ Microbiol ; 66(4): 1489-92, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10742231

RESUMO

The effect of X-ray irradiation on cell survival, induction, and repair of DNA damage was studied by using 10 Chroococcidiopsis strains isolated from desert and hypersaline environments. After exposure to 2.5 kGy, the percentages of survival for the strains ranged from 80 to 35%. In the four most resistant strains, the levels of survival were reduced by 1 or 2 orders of magnitude after irradiation with 5 kGy; viable cells were recovered after exposure to 15 kGy but not after exposure to 20 kGy. The severe DNA damage evident after exposure to 2.5 kGy was repaired within 3 h, and the severe DNA damage evident after exposure to 5 kGy was repaired within 24 h. The increase in trichloroacetic acid-precipitable radioactivity in the culture supernatant after irradiation with 2.5 kGy might have been due to cell lysis and/or an excision process involved in DNA repair. The radiation resistance of Chroococcidiopsis strains may reflect the ability of these cyanobacteria to survive prolonged desiccation through efficient repair of the DNA damage that accumulates during dehydration.


Assuntos
Cianobactérias/efeitos da radiação , Tolerância a Radiação , Radiação Ionizante , Cianobactérias/crescimento & desenvolvimento , Dano ao DNA , Reparo do DNA , Dessecação , Doses de Radiação , Raios X
6.
Int J Dermatol ; 38(8): 623-7, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10487456

RESUMO

BACKGROUND: Fly maggots have been known for centuries to help debride and heal wounds. Maggot therapy was first introduced in the USA in 1931 and was routinely used there until the mid-1940s in over 300 hospitals. With the advent of antimicrobiols, maggot therapy became rare until the early 1990s, when it was re-introduced in the USA, UK, and Israel. The objective of this study was to assess the efficacy of maggot therapy for the treatment of intractable, chronic wounds and ulcers in long-term hospitalized patients in Israel. METHODS: Twenty-five patients, suffering mostly from chronic leg ulcers and pressure sores in the lower sacral area, were treated in an open study using maggots of the green bottle fly, Phaenicia sericata. The wounds had been present for 1-90 months before maggot therapy was applied. Thirty-five wounds were located on the foot or calf of the patients, one on the thumb, while the pressure sores were on the lower back. Sterile maggots (50-1000) were administered to the wound two to five times weekly and replaced every 1-2 days. Hospitalized patients were treated in five departments of the Hadassah Hospital, two geriatric hospitals, and one outpatient clinic in Jerusalem. The underlying diseases or the causes of the development of wounds were venous stasis (12), paraplegia (5), hemiplegia (2), Birger's disease (1), lymphostasis (1), thalassemia (1), polycythemia (1), dementia (1), and basal cell carcinoma (1). Subjects were examined daily or every second day until complete debridement of the wound was noted. RESULTS: Complete debridement was achieved in 38 wounds (88.4%); in three wounds (7%), the debridement was significant, in one (2.3%) partial, and one wound (2.3%) remained unchanged. In five patients who were referred for amputation of the leg, the extremities was salvaged after maggot therapy. CONCLUSIONS: Maggot therapy is a relatively rapid and effective treatment, particularly in large necrotic wounds requiring debridement and resistant to conventional treatment and conservative surgical intervention.


Assuntos
Larva , Úlcera da Perna/terapia , Úlcera por Pressão/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Desbridamento/métodos , Feminino , Seguimentos , Humanos , Israel , Úlcera da Perna/diagnóstico , Úlcera da Perna/fisiopatologia , Masculino , Pessoa de Meia-Idade , Úlcera por Pressão/diagnóstico , Úlcera por Pressão/fisiopatologia , Resultado do Tratamento , Cicatrização/fisiologia
8.
J Occup Environ Med ; 39(5): 442-7, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9172089

RESUMO

Circumstances of injury were abstracted from police reports for 1835 convenience store robberies that occurred during 1992 or 1993 in selected metropolitan areas of seven eastern states. Subset analyses were performed using the data (758 robberies) from four states with relatively complete risk factor information. The purpose of this study was to estimate the risk of injury in a robbery situation for various risk factors. The overall risk of employee robbery-related injury could not be estimated because the probability of robbery is unknown. Of the 1835 robberies, 59% of the total robberies occurred at nighttime (9 p.m. to 3 a.m.), 47% occurred in stores previously robbed in the study period, 63% involved the use of a firearm, and 12% were associated with an injury to at least one employee. In the subset analysis of 758 robberies in four states, the employee probability of injury in a robbery was lower with firearm use compared with no weapon or use of a blunt instrument, and the probability of severe injury (defined as death, or an injury necessitating a trip to a hospital) was lower with a firearm compared with the use of a blunt instrument. However, all five fatalities were firearm-related. Other factors that were associated with a lower probability of employee injury included robbery occurrence in stores that had been robbed multiple times, compared with stores robbed only once; having 1 to 999 dollars stolen, compared with having no money stolen; and the presence of a customer(s) in the store at the time of the robbery. The employee risk of injury was not significantly different between one- (0.106) and multiple-employee (0.111) stores. Similarly, the employee risk of severe injury was not significantly different between one- (0.029) and multiple-employee stores (0.022). We conclude that there are several potential risk factors for employee injury in convenience store robberies, some of which are amenable to interventions. Further research on these factors and their relationship to employee injury is indicated.


Assuntos
Comércio/estatística & dados numéricos , Doenças Profissionais/epidemiologia , Roubo/estatística & dados numéricos , Ferimentos e Lesões/epidemiologia , Distribuição de Qui-Quadrado , Intervalos de Confiança , Feminino , Homicídio/estatística & dados numéricos , Humanos , Escala de Gravidade do Ferimento , Masculino , Estudos Multicêntricos como Assunto , Doenças Profissionais/economia , Fatores de Risco , Taxa de Sobrevida , Estados Unidos/epidemiologia , População Urbana , Ferimentos e Lesões/etiologia
9.
J Occup Environ Med ; 38(7): 714-20, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8823663

RESUMO

The number of robberies and robbery-related injuries to employees in convenience stores (C-stores) during 1992 or 1993 were estimated for selected metropolitan areas around Miami and Tampa, Florida; Atlanta, Georgia; Chicago, Illinois; Baltimore, Maryland; Boston, Massachusetts; Detroit, Michigan; Pittsburgh and Philadelphia, Pennsylvania; Charleston, Columbia, Greenville, and Spartanburg, South Carolina; and Arlington, Chesterfield, and Henrico counties, Virginia. Of the 1835 C-store robberies that occurred during 1992 or 1993 in all selected areas (excluding Atlanta and Chicago), there were 12 homicides of C-store employees; 219 nonfatal injuries of C-store employees; 1071 robberies in which there were no injuries but a weapon was used, displayed, or implied toward a C-store employee; and 132 robberies in which there was no injury and no weapon used, but an employee was struck, pushed, or shoved. Corresponding figures for the 238 robberies that occurred in Chicago during January to June 1993, and for which victim employment status was unknown (customer or employee) were three homicides, 53 nonfatal injuries, 120 attacks in which a weapon was used but there was no injury, and 57 attacks in which a person was struck, pushed, or shoved but there was no injury. The proportion of robberies that resulted in a homicide or injury to an employee varied among selected areas from .03 to .25. The proportion of homicides and injuries to an employee was. 14 or higher for target areas in Baltimore (.24), Detroit (.25), and Virginia (.14); the proportion to an employee or customer was .24 in Chicago. The conclusions from these data are that the risk of employee injury in C-store robberies was high in selected metropolitan areas. This underscores the need for effective robbery prevention programs to reduce injury. In addition, further research is needed to determine the effectiveness of prevention programs in the C-store industry and the application of these programs to other retail industries.


Assuntos
Comércio/estatística & dados numéricos , Doenças Profissionais/epidemiologia , Roubo/estatística & dados numéricos , Ferimentos e Lesões/epidemiologia , Coleta de Dados/métodos , Homicídio/estatística & dados numéricos , Humanos , Estados Unidos/epidemiologia , População Urbana
10.
Adv Space Res ; 15(3): 243-6, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11539232

RESUMO

The primitive characteristics of the cyanobacterium Chroococcidiopsis suggest that it represents a very ancient type of the group. Its morphology is simple but shows a wide range of variability, and it resembles certain Proterozoic microfossils. Chroococcidiopsis is probably the most desiccation-resistant cyanobacterium, the sole photosynthetic organism in extreme arid habitats. It is also present in a wide range of other extreme environments, from Antarctic rocks to thermal springs and hypersaline habitats, but it is unable to compete with more specialized organisms. Genetic evidence suggests that all forms belong to a single species. Its remarkable tolerance of environmental extremes makes Chroococcidiopsis a prime candidate for use as a pioneer photosynthetic microorganism for terraforming of Mars. The hypolithic microbial growth form (which lives under stones of a desert pavement) could be used as a model for development of technologies for large-scale Martian farming.


Assuntos
Cianobactérias/metabolismo , Cianobactérias/fisiologia , Microbiologia Ambiental , Meio Ambiente Extraterreno , Marte , Agricultura , Regiões Antárticas , Clima Frio , Cianobactérias/crescimento & desenvolvimento , Clima Desértico , Ecologia , Microbiologia do Solo
11.
Schweiz Rundsch Med Prax ; 83(17): 519-24, 1994 Apr 26.
Artigo em Alemão | MEDLINE | ID: mdl-8191196

RESUMO

The incidence of tuberculosis is increasing in many of the industrialized countries, mainly due to the spreading of HIV infections, the migration from countries with high prevalence of tuberculosis and possibly through the increase of the aged population. In 10 to 25% of the cases, tuberculosis manifests itself in extrapulmonary organs. One of the most frequent locations is the spine. The symptoms of the TB spondylitis are unspecific, and the course is creeping, which makes an early diagnosis difficult. Because of the frequent, severe complications, this must be attempted. In patients belonging to a risk group or with known exposition to tuberculosis and vertebral pain, the TB spondylitis must be included in the differential diagnosis. Combined chemotherapy is the key to successful therapy and can make surgical interventions or immobilization unnecessary. Two cases are presented, and the disease of the TB spondylitis is discussed.


Assuntos
Dor nas Costas/etiologia , Espondilite/diagnóstico , Tuberculose da Coluna Vertebral/complicações , Adulto , Antituberculosos/administração & dosagem , Antituberculosos/uso terapêutico , Quimioterapia Combinada , Feminino , Humanos , Imageamento por Ressonância Magnética , Abscesso do Psoas/complicações , Abscesso do Psoas/diagnóstico , Espondilite/microbiologia , Tomografia Computadorizada por Raios X , Tuberculose da Coluna Vertebral/diagnóstico , Tuberculose da Coluna Vertebral/tratamento farmacológico
12.
Phycologia ; 32(5): 315-22, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-11539431

RESUMO

Young and old cultures (up to 66 months) of two Chroococcidiopsis sp. strains isolated from the Negev desert, Israel, were examined by epifluorescence and electron microscopy. In old cultures, cell viability and autofluorescence were lower than in young cultures. An increase was seen with age in the polysaccharide content of the sheaths of nanocytes and nanocyte mother cells, and a decrease of phycobiliproteins was also seen. In the oldest cultures most of the cells were dead and in various stages of degeneration. Single living cells were scattered among the dead ones. No resting cells were formed in the oldest cultures, but many cell groups showed highly electron-dense sheaths and, in the cytoplasm, ribosomes and glycogen. These changes in cell structure may have a role in preventing water loss from the cell.


Assuntos
Cianobactérias/citologia , Cianobactérias/ultraestrutura , Clima Desértico , Dessecação , Microbiologia Ambiental , Adaptação Fisiológica , Divisão Celular , Cianobactérias/fisiologia , Israel , Microscopia Eletrônica , Microscopia de Fluorescência , Fatores de Tempo
13.
Antarct J US ; 28(5): 252-4, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-11539461

RESUMO

NASA: Researchers report results of laboratory studies of over 200 microbial strains of fungi, algae, cyanobacteria, and heterotrophic bacteria collected in the Ross Desert region of Antarctica. All of the 35 fungal strains produced substances that inhibited the growth of cyanobacteria and algae. The inhibitory effect of the biologically active substance was evident in crushed cell extract but less in spent broth.^ieng


Assuntos
Fatores Biológicos/farmacologia , Clorófitas/efeitos dos fármacos , Cianobactérias/efeitos dos fármacos , Fungos/química , Líquens/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Regiões Antárticas , Fatores Biológicos/isolamento & purificação , Fatores Biológicos/metabolismo , Biotecnologia , Clima Frio , Microbiologia Ambiental , Fungos/metabolismo , Fungos/fisiologia , Microbiologia Industrial , Testes de Sensibilidade Microbiana
14.
Schizophr Bull ; 19(3): 563-77, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8235459

RESUMO

Childhood attentional and neuromotor precursors of social competence and affective deficits in adolescents at risk for schizophrenia, adolescents at risk for affective disorder, and matched comparison adolescents were examined. The subjects were offspring of parents with schizophrenia or affective disorder and of normal parents matched on age, sex, and socioeconomic status from the New York High-Risk Project (Sample B). On the basis of interviews conducted when the subjects were children and adolescents, social competence was rated from child reports and parent reports, affective deficits were assessed by affective flattening ratings, and smiling was assessed by counting broad smiles. Adolescents at risk for schizophrenia had significantly greater social and affective deficits than adolescents at risk for affective disorder and comparison adolescents. In subjects at risk for schizophrenia, childhood neuromotor dysfunction predicted adolescent affective flattening, and childhood attentional dysfunction predicted adolescent social deficits. The results suggest that affective and social deficits in schizophrenia have different childhood precursors.


Assuntos
Transtornos Psicóticos Afetivos/diagnóstico , Filho de Pais com Deficiência/psicologia , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico , Ajustamento Social , Adolescente , Transtornos Psicóticos Afetivos/genética , Transtornos Psicóticos Afetivos/psicologia , Sintomas Afetivos/diagnóstico , Sintomas Afetivos/genética , Sintomas Afetivos/psicologia , Atenção , Criança , Seguimentos , Humanos , Relações Interpessoais , Estudos Longitudinais , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Transtornos Psicomotores/diagnóstico , Transtornos Psicomotores/genética , Transtornos Psicomotores/psicologia , Fatores de Risco , Esquizofrenia/genética , Sorriso , Escalas de Wechsler
15.
J Br Interplanet Soc ; 46: 291-2, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-11540501

RESUMO

One of the most difficult tasks in terraforming Mars is the release into the atmosphere of CO2 bound by the surface of Mars. Even if a sufficiently dense CO2 atmosphere can be created by appropriate technology, the maintenance of CO2 concentration remains a problem. As Mars lacks plate tectonics as well as active volcanism, an Earth-like carbon cycle cannot be reproduced there. We suggest that Matteia sp., a lime-boring cyanobacterium isolated from Negev desert rocks, be used to dissolve carbonate rocks both for initial release of CO2 and in design of a Martian carbon cycle.


Assuntos
Atmosfera , Dióxido de Carbono/metabolismo , Carbonatos/metabolismo , Cianobactérias/metabolismo , Marte , Microbiologia do Solo , Carbonato de Cálcio/metabolismo , Cianobactérias/classificação , Clima Desértico , Evolução Planetária , Exobiologia , Nitrogênio/metabolismo
16.
J Chromatogr ; 598(2): 267-76, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-11538045

RESUMO

Saponified extracts of rock samples colonized by cryptoendolithic microbial communities from the McMurdo Dry Valleys of Southern Victoria Land, Antarctica, were separated into hydrocarbon and fatty acid fractions by silica gel column chromatography. Hydrocarbons and methyl esters of fatty acids were analyzed by capillary gas chromatography-mass spectrometry. Unusually, a suite of long-chain anteiso-alkanes (a-C20 to a-C30) and anteiso-alkanoic acids (a-C20 to a-C30) were detected in many samples, together with straight-chain, branched and/or cyclic and acyclic isoprenoid compounds. These novel compounds are probably derived from unidentified heterotrophic bacteria or symbiotic processes in a unique microbial community in the Antarctic cold desert and suggest the occurrence of a special biosynthetic pathway. Long-chain anteiso-alkanes are probably formed through microbial decarboxylation of corresponding anteiso-alkanoic acids. They may serve as new biomarkers in environmental and geochemical studies.


Assuntos
Alcanos/análise , Bactérias/química , Ácidos Carboxílicos/análise , Ácidos Graxos/análise , Hidrocarbonetos/análise , Líquens/química , Alcanos/química , Regiões Antárticas , Ácidos Carboxílicos/química , Microbiologia Ambiental , Fósseis , Cromatografia Gasosa-Espectrometria de Massas , Fenômenos Geológicos , Geologia , Solo
17.
J Med Chem ; 34(1): 281-90, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1846920

RESUMO

Investigation of tricyclic heterocycles related to the 2-arylpyrazolo[4,3-c]quinolin-3(5H)-ones, structures with high affinity for the benzodiazepine (BZ) receptor, led to the synthesis of 2-phenyl-[1,2,4]triazolo[1,5-c]quinazolin-5(6H)-one, a compound with 4 nM binding affinity to the BZ receptor. Analogues were prepared to assess the importance of the 2-substituent and ring substitution in modifying activity. Several novel synthetic routes were designed to prepare the target compounds, including a two-step synthesis beginning with an anthranilonitrile and a hydrazide. Of the 34 compounds screened in this series, three compounds were found to be potent BZ antagonists in rat models. The leading compound, 9-chloro-2-(2-fluorophenyl) [1,2,4]triazolo[1,5- c]quinazolin-5(6H)-one (CGS 16228), showed activity comparable to that of CGS 8216 from the pyrazolo[4,3-c]quinoline series.


Assuntos
Encéfalo/metabolismo , Quinazolinas/síntese química , Receptores de GABA-A/metabolismo , Triazóis/síntese química , Animais , Ligação Competitiva , Diazepam/metabolismo , Flunitrazepam/metabolismo , Indicadores e Reagentes , Estrutura Molecular , Quinazolinas/química , Quinazolinas/farmacologia , Ratos , Receptores de GABA-A/efeitos dos fármacos , Relação Estrutura-Atividade , Triazóis/química , Triazóis/farmacologia
18.
Proc Natl Acad Sci U S A ; 86(10): 3842-6, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2542948

RESUMO

Dipyridamole (DPM) is commonly used as a coronary vasodilator and inhibitor of platelet aggregation in the treatment of cardiovascular diseases. We report here that DPM potentiates the inhibitory effects of 3'-azido-3'-deoxythymidine (AZT) and 2',3'-dideoxycytidine against human immunodeficiency virus type 1 (HIV-1) in human monocyte-macrophages. At the same concentrations, DPM does not potentiate the toxic effects of AZT on these cells or on human bone marrow (granulocyte-monocyte) progenitor cells. Since monocyte-macrophage lineage cells appear to be the major reservoir for HIV-1 in vivo, these findings suggest the possibility of using DPM or its analogues in combination chemotherapy of HIV infections.


Assuntos
Antivirais , Dipiridamol/administração & dosagem , HIV/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Zidovudina/administração & dosagem , Transporte Biológico , Medula Óssea/efeitos dos fármacos , Células da Medula Óssea , Sobrevivência Celular/efeitos dos fármacos , Didesoxinucleosídeos/metabolismo , Sinergismo Farmacológico , HIV/crescimento & desenvolvimento , Humanos , Técnicas In Vitro , Interferon Tipo I/biossíntese , Macrófagos/efeitos dos fármacos , Monócitos/efeitos dos fármacos , Zalcitabina
19.
J Med Chem ; 31(5): 1014-20, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-3361572

RESUMO

During a search for benzodiazepine receptor modulators, a highly potent adenosine antagonist (CGS 15943) was discovered. The compound was defined as a resonance-stabilized hybrid of the canonical structures 9-chloro-2-(2-furyl)[1,2,4]triazolo[1,5-c]quinazolin-5-amine (2a) and 9-chloro-2-(2-furyl)-5,6-dihydro[1,2,4]triazolo[1,5-c]-quinazolin- 5-imine (2b). Spectroscopic evidence and chemical reactivity in polar media favor the amine form 2a as the major contributor of the two canonical structures. The synthesis of 2 and some of its analogues and the structure-activity relationships in four biological test systems are described. Replacement of the 9-chloro group by hydrogen, hydroxyl, or methoxyl gave compounds with comparable binding potency at the A1 and A2 receptors but much less activity as antagonists of 2-chloroadenosine in guinea pig tracheal strips. Alkylation of the 5-amino group caused, in general, a loss of binding activity, particularly at the A2 receptor, as well as complete loss of activity in the tracheal model. Modification of the 2-furyl group caused a pronounced loss of activity in all of the test systems.


Assuntos
Adenosina/antagonistas & inibidores , Quinazolinas/síntese química , Triazóis/síntese química , Animais , Fenômenos Químicos , Química , Cobaias , Técnicas In Vitro , Conformação Molecular , Músculo Liso/efeitos dos fármacos , Quinazolinas/farmacologia , Ratos , Receptores Purinérgicos/efeitos dos fármacos , Relação Estrutura-Atividade , Triazóis/farmacologia
20.
Polarforschung ; 58(2-3): 121-4, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-11538353

RESUMO

Growth responses to temperatures between 12.5 [degrees] C and 25 degrees C were determined for five photosynthetic microorganisms isolated from the Ross Desert cryptoendolithic community. Among eukaryotic algae, two strains of Trebouxia sp. have an upper temperature limit of 20 degrees C, and two strains of Hemichloris antarctica of 25 degrees C. The cyanobacterium Chroococcidiopsis sp., in contrast, grows at temperatures above 25 degrees C. These and earlier studies suggest that the eukaryotic algae of the Antarctic cryptoendolithic community have an upper temperature limit near 25 degrees C.


Assuntos
Cianobactérias/crescimento & desenvolvimento , Cianobactérias/fisiologia , Fotossíntese/fisiologia , Temperatura , Regiões Antárticas , Cianobactérias/isolamento & purificação , Ecologia , Fenômenos Geológicos , Geologia
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