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1.
Artigo em Inglês | MEDLINE | ID: mdl-38248488

RESUMO

The occurrence of severe and extreme weather events that have been attributed to a changed climate system and the widespread dissemination of the impacts of these events in the media can lead people to experience concern, worry, and anxiety, which we examined in two studies. In Study 1, we observed that people more frequently expressed worry than anxiety about the impacts of climate change in six areas. People were more frequently worried and anxious about the effects of climate change on future generations and about societal responses (or lack of a response) to climate change. The levels of anxiety that people expressed were significantly higher than the worry people reported when anxiety was their modal response. In Study 2, we observed that both climate change worry and anxiety were negatively correlated with psychological distance from climate change. Overall, climate change worry and psychological distance significantly predicted climate-sustainable behaviors. Our study was among the first to use developed measures of climate change worry, anxiety, and psychological distance to examine peoples' responses across some of the possible impact and consequence areas of climate change.


Assuntos
Mudança Climática , Clima Extremo , Humanos , Ansiedade/epidemiologia , Transtornos de Ansiedade , Distância Psicológica
2.
J Clin Endocrinol Metab ; 46(4): 567-71, 1978 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-113423

RESUMO

This study evaluated the effects of adrenergic agents on immunoreactive calcitonin (iCT) secretion in normal man, and compared the time course and magnitude of these adrenergic effects with those caused by modifying calcium (Ca) ion concentration. Ca infusion (15 mg Ca++/kg iv in 4 h) significantly increased plasma iCT within 1 h, reaching 140 +/- 8% of baseline at 4 h. EDTA (50 mg/kg iv in 2 h) significantly decreased plasma iCT within 15 min, with nadir value of 53 +/- 4.9% of baseline at 2 h. The beta-adrenergic agonist, isoproterenol, significantly increased plasma iCT with 5 min, reaching 136 +/- 5.9% of baseline at 30 min. The alpha-adrenergic antagonist, phentolamine, significantly increased iCT within 15 min, reaching 132 +/- 8.6% of baseline at 45 min. The beta-adrenergic antagonist, propranolol, significantly suppressed iCT with 15 min, reaching 51.8 +/-6.3% of baseline at 2 h. Therefore, 1) the adrenergic system (without induced change in serum Ca) can modify CT secretion to as great a degree as can change in Ca ion concentration induced by standard Ca and EDTA infusion tests and 2) even basal secretion of CT can be modified by adrenergic influences. These data strongly suggest 1) that the adrenergic system is an effective modifier of CT secretion and 2) that the adrenergic system, as well as Ca ion concentration, may play an improtant physiological role in control of CT secretion in man.


Assuntos
Calcitonina/metabolismo , Cálcio , Isoproterenol , Fentolamina , Propranolol , Adulto , Ácido Edético , Humanos , Cinética , Masculino , Pessoa de Meia-Idade
3.
J Clin Endocrinol Metab ; 52(1): 122-7, 1981 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7451639

RESUMO

The effect of histamine and histamine H2 receptors on secretion off parathyroid hormone (PTH) was evaluated by 1) adding histamine phosphate (with or without the histamine H2 receptor antagonist, cimetidine) to the medium in in vitro incubation studies with bovine parathyroid tissue, 2) infusing histamine into rats, and 3) infusing the histamine H1 receptor antagonist, diphenhydramine, or cimetidine into normal men and patients with primary hyperparathyroidism. In vitro, histamine (10(-5)-10(-7) M) caused a dose-related significant stimulation of immunoreactive PTH (iPTH) secretion; this was blocked by the simultaneous addition of cimetidine (10(-5) M). Intravenous infusion of histamine significantly increased serum iPTH in rats. In normal man, infusion of diphenhydramine had no effect, but cimetidine (300 or 450 mg) significantly decreased serum iPTH. However, cimetidine had no effect on serum iTh in primary hyperparathyroid patients. The in vitro observations indicate that histamine can stimulate iPTH secretion by a direct effect on the parathyroid cell and that this is probably a specific effect via histamine H2 receptors because the effect was blocked by the H2 receptor antagonist, cimetidine. The observed inhibition of basal PTH concentration by cimetidine induced histamine H2 receptor blockade (but not by H1 blockade) in normal human subjects suggests that endogenous histamine with H2 receptor activation stimulates even basal PTH secretion and may serve as a modulator of PTH secretion in normal man. Loss of this modulating effect of H2 receptors on PTH secretion is a characteristic of primary hyperparathyroidism.


Assuntos
Hiperparatireoidismo/fisiopatologia , Hormônio Paratireóideo/metabolismo , Receptores Histamínicos H2/fisiologia , Receptores Histamínicos/fisiologia , Adulto , Animais , Bovinos , Cimetidina , Difenidramina , Relação Dose-Resposta a Droga , Histamina/farmacologia , Humanos , Técnicas In Vitro , Cinética , Masculino , Pessoa de Meia-Idade , Glândulas Paratireoides/efeitos dos fármacos , Ratos
4.
Ecol Appl ; 1(2): 196-206, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-27755668

RESUMO

Ecological risk assessments are used by policy makers and regulatory agencies for balancing and comparing ecological risks associated with environmental hazards. An approach for regional-scale ecological risk assessment is described and demonstrated by modeling environmental risks associated with elevated ozone in a forested region. The demonstration illustrates (1) how a regional-scale risk assessment might be done, (2) the importance of spatial characteristics in considering regional-scale risk, and (3) the necessity of considering terrestrial and aquatic linkages. Generic problems often encountered when doing regional assessments, the foremost of which is the frequent lack of region-specific information and spatial data, are also highlighted. In the demonstration, two levels of elevated ozone and five different at-risk regional features are considered (forest cover, forest edge, forest interior, landscape pattern, and lake water quality). The mechanism for impacts on these features is ozone-induced stress in coniferous trees, patches of which can then be killed by bark beetle attacks. A stochastic spatial model of land-cover change is developed to evaluate the risks or probabilities of significant changes in the selected ecological features as a consequence of these ozone-triggered beetle attacks. Risk to regional water quality of lakes is evaluated by linking the land-cover output from the spatial stochastic model to an empirical water-quality model that is sensitive to land-cover changes within a lake's watershed. The risk analysis shows that those environmental features that are sensitive to the location of coniferous forest (such as forest edge) are at risk of a significant change due to ozone-induced conifer mortality even though overall coniferous forest cover is only slightly affected. The analysis also suggests a high probability of changes in regional water quality of lakes as a consequence of location-specific forest-cover change.

5.
Clin Chim Acta ; 138(2): 185-96, 1984 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-6586330

RESUMO

Thermolabile (TL) and thermostable (TS) forms of human platelet phenol sulfotransferase (PST) were measured over various periods of time. TL PST was assayed with dopamine as the substrate and TS PST was measured with phenol and with p-nitrophenol. Levels of TL and TS PST from the same subjects did not change significantly over 1 day, 1 week, 4 weeks, and 8.5 months. Interassay coefficients of variation of PST activities over 3-4 weeks measured in samples from 8-12 subjects with dopamine, phenol and p-nitrophenol were 13.96%, 13.60% and 13.30%, respectively. There was a significant correlation between PST activity measured in the same samples with phenol and with p-nitrophenol (r = 0.946, n = 18, p less than 0.0001). TS PST activity measured with p-nitrophenol was significantly higher (p less than 0.0001) in platelets from 51 black subjects than the level of TS PST in samples from 52 white subjects (0.72 +/- 0.06 vs 0.42 +/- 0.04 units/10(8) platelets, respectively; mean +/- SEM). These results demonstrate the 'stability' of the levels of both forms of the enzyme with time. They also point out the usefulness of a reproducible assay for the detection of a racial difference in the levels of TS PST.


Assuntos
Plaquetas/enzimologia , Grupos Raciais , Sulfurtransferases/sangue , Adulto , Animais , Arilsulfotransferase , Feminino , Humanos , Masculino , Menstruação , Ratos , Ratos Endogâmicos , Especificidade da Espécie , Especificidade por Substrato , Sulfurtransferases/genética
6.
J Am Dent Assoc ; 100(1): 43-7, 1980 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6927885

RESUMO

The comparison of clinically retrieved conventional and copper-rich amalgam restorations demonstrated that there are at least two distinct types of compounds that form in vivo in amalgam restorations, tin-rich layers on the exposed surface of many amalgams and tin-chlorine and smaller amounts of stannous oxide products in the interior. In the systems rich in copper, corrosion was confined to the surface and a few isolated areas. The relatively small changes found in the systems rich in copper could account for the superior marginal integrity reported for copper-rich amalgams in clinical trials.


Assuntos
Cobre , Amálgama Dentário , Fenômenos Químicos , Físico-Química , Cloro/análise , Cobre/análise , Amálgama Dentário/análise , Restauração Dentária Permanente , Mercúrio , Oxigênio , Prata , Propriedades de Superfície , Estanho/análise
8.
J Lab Clin Med ; 112(6): 773-83, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3193032

RESUMO

Phenol sulfotransferase (PST) catalyzes the sulfate conjugation of catecholamines and of phenolic drugs. Human platelet PST exists in at least a thermolabile form (TL PST) and a thermostable form (TS PST). The mean basal level of platelet TS PST activity in samples from American blacks is significantly higher than the basal activity in samples from whites. We carried out the studies reported here to determine whether the higher basal TS PST activity in platelet homogenates from blacks was biochemically similar to the lower basal activity in samples from whites. We also characterized variations in TS PST thermal stability. Platelet TS PST activities in samples from the two groups were almost identical with respect to pH optima, Michaelis-Menten constant values for substrates, and susceptibilities to inhibition by 2,6-dichloro-4-nitrophenol and sodium chloride. Thermolabile and thermostable TS PST were present in samples from both blacks and whites. Thermal stabilities of TS PST in samples from 167 volunteers (104 blacks, 63 whites) were expressed as heated sample-to-control sample ratios. Bimodal frequency distribution histograms of the heated-to-control ratios revealed subgroups of samples with thermolabile TS PST activities from 13.5% of blacks (heated-to-control ratio less than 0.32) and 12.7% of whites (heated-to-control ratio less than 0.27). The mean heated-to-control ratio for thermostable TS PST from blacks was significantly higher than that from whites (0.52 +/- 0.01 vs 0.43 +/- 0.01, respectively, mean +/- SEM; p less than 0.0001). Our studies demonstrated the similarity of biochemical properties of platelet TS PST at the extremes of basal activity. They also showed equivalent subgroups of blacks and whites with thermolabile TS PST. The results are an important initial step toward testing the hypothesis that inheritance may be one factor in the regulation of basal levels of activities and thermal stabilities of platelet TS PST from American blacks.


Assuntos
Arilsulfotransferase/sangue , Plaquetas/enzimologia , Adulto , Arilsulfotransferase/antagonistas & inibidores , Arilsulfotransferase/genética , População Negra , Estabilidade Enzimática , Feminino , Temperatura Alta , Humanos , Concentração de Íons de Hidrogênio , Cinética , Masculino , Nitrofenóis/farmacologia , Concentração Osmolar , População Branca
9.
Neuroendocrinology ; 44(1): 117-24, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3466054

RESUMO

Pituitary tissue contains phenol sulfotransferase (PST), the enzyme that catalyzes the sulfate conjugation of monoamine neurotransmitters. We carried out these studies with pituitaries obtained 21.3 +/- 3.0 h postmortem (mean +/- SEM; n = 21) to determine whether the biochemical properties and variations in levels of human pituitary PST activities were similar to those of PST in platelets from control subjects. PST in the human platelet has been studied thoroughly because of the possibility that platelet PST might reflect levels of PST activity in other tissues such as the pituitary and brain. Our results demonstrated 2 forms of the pituitary enzyme that were similar to the thermostable (TS) and thermolabile (TL) forms of platelet PST with regard to assay conditions, pH optima, Km values for multiple substrates, responses to 2,6-dichloro-4-nitrophenol (DCNP), and thermal stability properties. Pituitary samples also were obtained at autopsy 6.3 +/- 0.33 h (mean +/- SEM; n = 3) after death to determine the effects of storage at 4 degrees C on PST activities. After storage for 6-18 h, 83-99.6% of the TS PST activity remained and 44-66.9% of the TL PST activity remained. Pituitary TS PST activity in samples obtained within 12.1 +/- 3.25 h after death was 121.0 +/- 49.1 units/mg protein (mean +/- SEM; n = 7) with a range from 9.7 to 367.6. TL PST activity was 35.6 +/- 11.6 units/mg protein (mean +/- SEM; n = 6) with a range from 6.1 to 80.7. Wide variations of both enzyme activities were also present in 3 pituitary tumor samples.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Hipófise/enzimologia , Sulfurtransferases/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Arilsulfotransferase , Temperatura Baixa , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Pessoa de Meia-Idade , Preservação de Órgãos , Mudanças Depois da Morte , Temperatura , Fatores de Tempo
10.
J Manipulative Physiol Ther ; 10(4): 157-63, 1987 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3655565

RESUMO

To determine the degree of reliability (stability over time) for six Pettibon practitioners, the scores resulting from the reading and re-reading of 30 X rays were analyzed using bivariate scattergrams, Pearson Product-moment correlation coefficient estimates and correlated samples t tests. To examine reliability (equivalence over experts) across the practitioners, a repeated measures analysis of variance approach was used. Liberal and conservative reliability coefficients for the upper angle and lower angle were computed. Examination of the data suggest that the reliability (stability over time) for the practitioners is very good. The data on reliability (equivalence over experts) across the practitioners also suggests reliability is very good.


Assuntos
Vértebras Cervicais/diagnóstico por imagem , Doenças da Coluna Vertebral/diagnóstico por imagem , Diagnóstico Diferencial , Humanos , Manipulação Ortopédica , Radiografia , Doenças da Coluna Vertebral/terapia
11.
J Manipulative Physiol Ther ; 16(6): 384-91, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8409786

RESUMO

OBJECTIVE: To determine the degree to which the geometric line drawings used in Chiropractic Biophysics Technique (CBP) on lateral cervical radiographs are reliable. DESIGN: A blind, delayed repeated measures design was used. Three examiners were presented radiographs in random order. All identifying marks were removed prior to each examiner's individual marking and measurement. Each examiner was blinded as to how the previous examiners marked and measured the radiographs. SETTING: Primary care private chiropractic clinic. PARTICIPANTS: Sixty-five subject films were provided from the patient records of a primary care private chiropractic clinic. The 65 radiographs qualified for inclusion in the study based on two criteria: C1 through C7 had to be clearly visible, and there had to be no identifying artifacts. MAIN OUTCOME MEASURES: Anterior head translation in millimeters, atlas plane to horizontal, Ruth Jackson's cervical stress lines, and five relative rotation angles for C2-C3, C3-C4, C4-C5, C5-C6, C6-C7. Inter- and intrareliability of the three examiners were statistically analyzed. RESULTS: Intraexaminer for a) C1 to horizontal reliability was .98-.99 with confidence intervals of .96-.99, b) absolute rotation angle from C2 to C7 reliability was .82-.95 with confidence intervals of .80-.99, c) anterior head translation [+Sz] reliability was .86-.99, with confidence intervals of .74-.99, d) relative rotation angle reliability ranges were (C2-C3) .99, and (C3-C4) .98-.99, (C4-C5) .88-.99, (C5-C6) .80-.99, and (C6-C7) .94-.98. Interexaminer reliabilities across examiners ranged from a) Winer:.89-.99 and b) Bartko: .72-.96. CONCLUSIONS: The reliabilities for intra- and interexaminer were all greater than .70, indicating that these measurements in CBP technique would be considered accurate enough to provide measurements for future clinical studies. The data indicated that the C6-C7 relative rotation angle was the least reliable measurement. This might be due to the very small angles found at this level.


Assuntos
Vértebras Cervicais/diagnóstico por imagem , Quiroprática/métodos , Análise de Variância , Humanos , Variações Dependentes do Observador , Radiografia , Reprodutibilidade dos Testes
12.
J Manipulative Physiol Ther ; 17(7): 454-64, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7989879

RESUMO

OBJECTIVE: To experimentally investigate the effect of cervical extension-compression traction combined with diversified chiropractic manipulation and drop table adjusting in establishing or increasing cervical lordosis. DESIGN: Blinded, before and after trial with pre- and postlateral cervical radiographic measurement. SETTING: Primary care private chiropractic clinic in Saugus, MA. SUBJECTS: A) Control group--convenience sample who had no health care for 10-14 wk, 30 persons. B) Treatment group 1, nonrandomized control trial, 35 persons, whose pre- and postlateral cervical radiographs were taken 10-14 wk apart and whose radiographs clearly depicted C1 through C7. C) Treatment group 2, nonrandomized control trial, 30 persons, whose pre- and postlateral cervical radiographs were taken 10-14 wk apart and whose radiographs clearly depicted C1 through C7. INTERVENTIONS: Treatment group 1: diversified spinal manipulation, drop table adjustments and cervical extension-compression traction five times per week for 10-14 wk (12 wk +/- 2). Treatment group 2: diversified spinal manipulation and drop table adjustments five times per week for 10-14 wk (12 wk +/- 2). MAIN OUTCOME MEASURES: Anterior head translation millimeters, C2 to C7 absolute rotation angle, angle of C1 to horizontal (atlas plane angle), five relative rotation angles (C2-3, C3-4, C4-5, C5-6, C6-7) and qualitative classification of lordotic configuration. RESULTS: No statistically significant changes existed between the pre- and posttests for the control group except in the C6-7 relative rotation angle. In the treatment group 1, statistically significant differences were found in all X-ray markings. Twenty-nine of 35 members have a lordosis after treatment compared to 11 of 35 before treatment. The C2 to C7 angle changed an average 13.2 degrees, C1 to horizontal changed an average 9.8 degrees, the anterior head translation reduced an average of 6.8 mm, the average relative rotation angle changed: C2-3: 3.1, C3-4: 5.5, C4-5: 4.80, C5-6: 2.7 and C6-7: 1.1. In the treatment group 2, no statistically significant changes existed between the pre- and posttests except atlas angulation to horizontal which increased an average of 3.0 degrees. CONCLUSIONS: A transformation to a lordotic configuration or increase in lordotic configuration occurred and was measured in the majority of treatment group 1 subjects, while no change in the control group and essentially no change in treatment group 2 was measured. Extension-compression traction combined with diversified chiropractic manipulation and drop table adjusting procedures may improve or partially reestablish the cervical lordosis in 10-14 wk of daily care.


Assuntos
Vértebras Cervicais , Lordose/reabilitação , Manipulação Ortopédica/métodos , Tração/métodos , Adulto , Idoso , Análise de Variância , Vértebras Cervicais/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Radiografia
13.
Radiology ; 196(2): 421-6, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7617855

RESUMO

PURPOSE: To evaluate the complementary role of technetium-99m sestamibi scintimammography in improvement of the sensitivity and specificity of mammography in detection of carcinoma of the breast. MATERIALS AND METHODS: At 5 and 60 minutes after intravenous injection of Tc-99m sestamibi, scintimammograms were obtained in 147 women (age range, 18-73 years; mean age, 47.9 years +/- 10.2 [standard deviation]) with 153 lesions that warranted breast biopsy (102 lesions) or fine-needle aspiration cytologic analysis (51 lesions). There were 113 palpable and 40 nonpalpable lesions. Lesion size on mammograms was 0.8 x 0.6 cm to 15.0 x 11.0 cm (mean, 2.82 cm +/- 1.71 x 2.39 cm +/- 1.56). RESULTS: Scintimammographic findings were true-positive in 47 biopsy-confirmed carcinomas, true-negative in 91 benign lesions, false-positive in 11 lesions with benign histopathologic findings (fibrocystic disease [n = 8] or fibroadenoma [n = 3]), and false-negative in four lesions of infiltrating ductal carcinoma. The sensitivity of scintimammography was 92.2%; specificity, 89.2%; positive predictive value, 81.0%; and negative predictive value, 95.8%. CONCLUSION: The authors conclude that scintimammography is a sensitive test that can improve the detection of breast carcinoma.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Carcinoma in Situ/diagnóstico por imagem , Carcinoma Ductal de Mama/diagnóstico por imagem , Tecnécio Tc 99m Sestamibi , Biópsia por Agulha , Mama/patologia , Neoplasias da Mama/patologia , Carcinoma in Situ/patologia , Carcinoma Ductal de Mama/patologia , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Doença da Mama Fibrocística/diagnóstico por imagem , Doença da Mama Fibrocística/patologia , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Decúbito Ventral , Cintilografia , Sensibilidade e Especificidade
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