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1.
Nanoscale ; 7(6): 2301-5, 2015 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-25594494

RESUMO

We present here a study on the electrical conduction properties of individual polypyrrole nanobelts by using conductive atomic force microscopy and discuss a general effect while probing soft materials. A length-dependent analysis demonstrates that the tip could induce local defects into the polymer structure and, thus diminishes the electrical conduction.

2.
Cell Calcium ; 34(1): 87-96, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12767896

RESUMO

This is the first thorough study of refilling of a cortical calcium store in a secretory cell after stimulation in which we combined widely different methodologies. Stimulation of dense-core vesicle ("trichocysts") exocytosis in Paramecium involves a Ca(2+) -influx" superimposed to Ca(2+) -release from cortical stores ("alveolar sacs" (ASs)). In quenched-flow experiments, membrane fusion frequency rose with increasing [Ca(2+)](o) in the medium, from approximately 20-25% at [Ca(2+)](o) < or = 0.25 microM to 100% at [Ca(2+)](o) between 2 and 10 microM, i.e. close to the range of estimated local intracellular [Ca(2+)] during membrane fusion. Next, we analyzed Ca(2+)-specific fluorochrome signals during stimulation under different conditions. Treatment with actin-reactive drugs had no effect on Ca(2+) -signaling. In double trigger experiments, with BAPTA in the second secretagogue application (BAPTA only for stimulation and analysis), the cortical Ca(2+) -signal (due solely to Ca(2+) released from cortical stores) recovered with t(1/2) approximately 65 min. When ASs were analyzed in situ by X-ray microanalysis after different trigger times (+Ca(2+)(o)), t(1/2) for store refilling was similar, approximately 60 min. These values are similar to previously measured 45Ca(2+) -uptake by isolated ASs. In sum we find, (i) exogenous Ca(2+) increases exocytosis/membrane fusion performance with EC(50)=0.7 microM, (ii) Ca(2+) -signaling in this system is not sensitive to actin-reactive drugs, and (iii) refilling of these cortical calcium stores goes on over hours and thus is much slower than expected.


Assuntos
Sinalização do Cálcio/fisiologia , Cálcio/metabolismo , Organelas/metabolismo , Paramecium/metabolismo , Actinas/efeitos dos fármacos , Actinas/metabolismo , Animais , Cálcio/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Quelantes/farmacologia , Citoplasma/efeitos dos fármacos , Citoplasma/metabolismo , Exocitose/efeitos dos fármacos , Exocitose/fisiologia , Corantes Fluorescentes/farmacologia , Líquido Intracelular/efeitos dos fármacos , Líquido Intracelular/metabolismo , Membranas Intracelulares/efeitos dos fármacos , Membranas Intracelulares/metabolismo , Fusão de Membrana/efeitos dos fármacos , Fusão de Membrana/fisiologia , Organelas/efeitos dos fármacos , Paramecium/citologia , Paramecium/efeitos dos fármacos , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologia , Vesículas Secretórias/efeitos dos fármacos , Vesículas Secretórias/metabolismo
3.
Complement Ther Med ; 10(1): 46-8, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12442823

RESUMO

Several 'centres of excellence' of research in complementary/alternative medicine (CAM) have emerged in recent years. This study represents an attempt to profile the most productive of these centres. Medline searches (1995-2001) were performed with a long list of individuals directing CAM research groups as key words. Eight of them (all male) had published in excess of 20 Medline-listed articles between 1995-2001, and this group was evaluated in further detail. Three originated from the US and two from the UK. Collectively this group had published 32 clinical trials, an equal number of surveys and 95 systematic reviews. The range of research subjects for most centres was narrow. It is concluded that several active CAM research centres are well established. Their output is variable and, in most cases, leave room for improvement. Probably because of funding difficulties, clinical trials remain rare.


Assuntos
Terapias Complementares/normas , Indicadores de Qualidade em Assistência à Saúde , Ensaios Clínicos como Assunto , Alemanha , Humanos , Editoração/normas , Pesquisa/normas , Suíça , Reino Unido , Estados Unidos
5.
Anal Chem ; 72(5): 916-21, 2000 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-10739192

RESUMO

Creatinine-specific antibodies have been generated and used for highly sensitive and specific immunochemical creatinine determinations. Creatinine was derivatized at N3 and coupled to KLH carrier protein. On the basis of this immunogen, monoclonal antibodies were developed by hybridoma technology. Antibodies from various clones have been characterized with BIAcore 2000 with respect to the dissociation constant and specificity. Antibodies of clone B90-AH5 exhibited the lowest dissociation constant (0.74 microM) and the highest specificity for creatinine and were chosen for the development of a competitive ELISA and an amperometric creatinine sensor. The creatinine sensor was constructed by fixing a creatinine-modified membrane on the top of a platinum working electrode which was then incorporated into a stirred electrochemical measuring cell. For creatinine determination the creatinine-containing sample was incubated with B90-AH5 and anti-IgG(mouse)-glucose oxidase conjugate and applied to the measuring cell. After a washing step glucose was added and the produced hydrogen peroxide was registered at Eappl = +600 mV vs Ag/AgCl. The measuring range was 0.01-10 microg/mL. The highest sensitivity for creatinine was achieved at 330 ng/mL (3 microM) and the lower detection limit at 4.5 ng/mL (40 nM). This is far below the relevant clinical range, which is 5-17 microg/mL (44-150 microM) and allows a reliable determination of very low creatinine concentrations in serum, where standard methods cannot be applied. After each measurement the sensor was regenerated with 10 mM HCl without any loss in binding activity.


Assuntos
Técnicas Biossensoriais , Creatina/análise , Ensaio de Imunoadsorção Enzimática/métodos , Anticorpos Monoclonais/imunologia , Creatina/imunologia , Eletroquímica , Ensaio de Imunoadsorção Enzimática/normas , Humanos , Sensibilidade e Especificidade
6.
J Comput Assist Tomogr ; 24(2): 247-52, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10752886

RESUMO

PURPOSE: The purpose of this study was to evaluate the performance of electron beam tomography (EBT) in the dynamic and quantitative assessment of tracheal collapse in tracheomalacia. METHOD: Eight patients with suspected tracheomalacia were evaluated by EBT, and the results were correlated with both clinical symptoms and bronchoscopy. To validate this technique, an EBT phantom study preceded the patients' examination. A dynamic imaging sequence consisting of 20 50-ms scans obtained at 0.5 s intervals during a 10 s period was performed while the patient followed an instructed breathing maneuver. RESULTS: Good correlation between EBT data and clinical symptoms was found in all patients. In comparison to bronchoscopic findings, EBT results correlated well in three, showed limited correlation in three patients, and no correlation in one case. CONCLUSION: EBT with its short scanning time may be regarded as an accurate noninvasive method to dynamically evaluate tracheomalacia.


Assuntos
Broncoscopia , Pneumopatias Obstrutivas/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Estenose Traqueal/diagnóstico , Adulto , Idoso , Tosse/diagnóstico , Estudos de Avaliação como Assunto , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Transtornos Respiratórios/diagnóstico por imagem , Transtornos Respiratórios/fisiopatologia
7.
Curr Med Res Opin ; 15(3): 214-27, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10621929

RESUMO

OBJECTIVE: The common cold (acute viral respiratory tract infection) is one of the most frequent diseases in man, world-wide. Clinically relevant efficacy should include early improvement of all symptoms. Results of a clinical trial of a commercially available fixed combination herbal remedy (Radix echinaceae, Radix baptisiae, Herba thujae) are reported here. The aim of this study was to verify clinical efficacy shown in recent studies under (i) good clinical practice (GCP) quality assurance and (ii) common situations at family doctors. METHODS: Patients attending one of 15 study centres (practitioners) as a result of an acute common cold were randomised to the double-blind placebo-controlled study. Three tablets of study medication were applied t.i.d. for 7 to 9 days. Patients daily documented the intensity of 18 cold symptoms, as well as the cold overall, using a 10-point scale and estimated their general well-being using the Welzel-Kohnen colour scales. Additionally, the severity of illness was assessed by the physician on days 4 and 8 (CGI-1). The main and confirmatory outcome measure was expressed as a total efficacy value. This was gauged from the z-standardised AUC values of the primary endpoints (rhinitis score, bronchitis score, CGI-1 and general well-being). Adverse events, overall tolerability, vital signs and laboratory parameters were documented. RESULTS: 263 patients were included. For safety analysis, all patients were used. 259 patients were evaluable for primary efficacy analysis (ITT). Results were confirmed analysing only the 238 valid cases (VCs). The primary efficacy parameters showed the superiority of the herbal remedy over placebo (p < 0.05). Effect size was 20.6% of the standard deviation (90% CI: 0.04-41.1%; ITT) and 23.1% (1.7-44.5%; VC). In relation to the general well-being, the effect size was 33.9% of the standard deviation (12.5-55.3%; VC). Patients who suffered from at least moderate symptom intensity at baseline showed response rates (at least 50% improvement of the global score, day 5) of 55.3% in the herbal remedy group and 27.3% in the placebo group (p = 0.017; NNT = 3.5). In the subgroup of patients who started therapy at an early phase of their cold, the efficacy of the herbal remedy was most prominent (p = 0.014 for the primary efficacy parameter). The therapeutic benefit of the herbal remedy had already occurred on day 2 and reached significance (p < 0.05) on day 4, and continued until the end of the treatment in the totdl score of symptoms, bronchitis score and rhinitis score, as well as in the patients' overall rating of the cold intensity. At that time, equal levels of improvement were reached three days earlier in the verum group than in the placebo group. In 26 patients receiving the herbal remedy and 23 patients receiving placebo, adverse events were reported. Adverse drug reactions were suspected in two patients in the verum group and in four patients in the placebo group. Serious adverse events did not occur. CONCLUSIONS: This study shows that the herbal remedy is effective and safe. The therapeutic benefit consists of a rapid onset of improvement of cold symptoms. If patients with colds are able to start the application of the herbal remedy as soon as practical after the occurrence of the initial symptoms, the benefit would be expected to increase (e.g. self-medication).


Assuntos
Resfriado Comum/tratamento farmacológico , Fitoterapia , Extratos Vegetais/uso terapêutico , Adulto , Idoso , Análise de Variância , Qualidade de Produtos para o Consumidor , Método Duplo-Cego , Combinação de Medicamentos , Echinacea , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Plantas Medicinais
8.
Dtsch Med Wochenschr ; 121(50): 1553-60, 1996 Dec 13.
Artigo em Alemão | MEDLINE | ID: mdl-8998927

RESUMO

PROBLEM AND OBJECTIVE: Complementary medicine is being used to varying extent in all industrial countries. There are incomplete data concerning efficacy, safety and costs of such treatment, while little is known about special features and motivation of those persons who choose complementary medicine. The aim of the study was to ascertain, among patients who use complementary medicine and those who prefer traditional medicine, any differences with regard to sociodemographic, disease-related and psychological characteristics and their life-style. PATIENTS AND METHODS: A total of 419 patients were studied by a standardised interview and questionnaire (168 items) and divided into two groups (group 1: those using conventional treatment [n - 197; 91 women, 106 men; average age 43.2 +/- 16.9 years]; group 2: those preferring complementary medicine [n = 222; 159 women, 63 men; average age 43.2 +/- 15.0 years]). They were recruited from specialist internal medical or generalist medical practice with or without offer of complementary medicine (additional term: natural healing methods). Statistical analysis was with Student's-t-test and the chi(2)-test [correction of gamma-test]. RESULTS: Those patients who chose to be treated by complementary medicine clearly differed from the others with respect to sociodemographic, disease-related and psychological characteristics, as well as life-style. The patient-doctor relationship also differed between the two groups. On average those of group 2 had a higher educational level (higher education: 10.3% in group 1; 15.9 in group 2) and lower risk factors (68.9% nonsmokers in group 1, 77.8% in group 2; alcohol abstinence: 33.2 vs 46.4%). Patients in both groups preferred conventional medicine for serious diseases (cardiac infarct; tumour; AIDS). CONCLUSIONS: In general, those patients who choose complementary medicine have a healthier life-style. As the number of these patients is on the increase. Since as yet the efficacy, risks and costs of complementary medicine have been inadequately investigated, research in this area should be intensified.


Assuntos
Terapias Complementares/estatística & dados numéricos , Adulto , Escolaridade , Feminino , Alemanha , Humanos , Entrevistas como Assunto , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Relações Médico-Paciente , Fatores de Risco , Inquéritos e Questionários
9.
Fortschr Med ; 114(27): 349-50, 1996 Sep 30.
Artigo em Alemão | MEDLINE | ID: mdl-8999017

RESUMO

The rhizome of Curcuma xanthorrhiza has been used for medical purposes for hundreds of years. A related plant, but which contains other constituents, is C. domestica, which is used in the manufacture of curry powder. Both experimental and clinical studies have revealed, in particular, a choleretic effect. In addition, in part in animal experimental studies, antilipidemic, analgesic-antiphlogistic and antimicrobial effects have also been found.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Colagogos e Coleréticos/uso terapêutico , Curcumina/uso terapêutico , Plantas Medicinais , Humanos
10.
Versicherungsmedizin ; 48(4): 129-33, 1996 Aug 01.
Artigo em Alemão | MEDLINE | ID: mdl-8966850

RESUMO

In a special consulting office for complementary medicine, ambulatory patients interested in receiving adjuvant treatment with complementary medicine can obtain a relevant advice and critical information regarding non-evaluated therapies. Within the framework of a retrospective statistical analysis, the diagnosis documented over a period of 24 months in accordance with the 4-digit ICD code were evaluated. In particular patients with chronic and/or functional illnesses had additional treatment needs. The exponential growth in the numbers of patients during the course of the observation period illustrates the increasing importance of complementary medical measures. However, in view of the considerable political significance of the cost factor and the possible risks of the treatment, only properly evaluated complementary medical therapies should be employed.


Assuntos
Terapias Complementares/estatística & dados numéricos , Doença/classificação , Naturologia/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Equipe de Assistência ao Paciente/estatística & dados numéricos , Estudos Retrospectivos
11.
Fortschr Med ; 113(19): 291-2, 1995 Jul 10.
Artigo em Alemão | MEDLINE | ID: mdl-7672742

RESUMO

Fumaria officinalis-fumitory or earth smoke-is a medicinal plant which has long had a role to play in empirical medicine in numerous countries. A review of the literature, however, reveals very few studies that support its use for dermatological indications (milk crust, eczema, scabies, etc.) or as a diuretic or laxative. This contrasts with its use to treat functional diseases of the biliary system. Although no placebo-controlled studies have been done, a number of empirical reports, clinical case reports and animal experimental studies have been published. Accordingly, in Germany, Fumaria officinalis is approved for the indication "colicky pain affecting the gallbladder and biliary system, together with the gastrointestinal tract".


Assuntos
Medicina Tradicional , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Humanos
13.
Int J Risk Saf Med ; 7(1): 55-63, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-23511672

RESUMO

The prevalence of complementary medicine in most industrialised countries is impressive and increasing. Discussions of the topic often focus on therapeutic approaches and neglect diagnostic methods specific for complementary medicine. The paper summarises the data available on such "alternative" diagnostics. Scientific evaluations of these are scant, and most techniques have never been properly validated. The ones that have can be demonstrated to be not reproducible, sensitive, or specific. The ones that have not should be regarded as such until shown otherwise by rigorous testing. Therefore it seems that "alternative" diagnostic methods may seriously threaten the safety and health of patients submitted to them. Orthodox doctors should be aware of the problem and inform their patients accordingly.

16.
Acta Med Austriaca ; 21(5): 121-4, 1994.
Artigo em Alemão | MEDLINE | ID: mdl-7709708

RESUMO

Contact regulation thermography is one of the unconventional medical diagnostic procedures, and is based on the individual adaptive behavior of the subject with respect to temperature. Its proponents believe that a specific medical diagnosis can be established on the basis of varying temperature differences. Studies carried out to date have produced mixed results. The increasing use of this procedure, not only in complementary medicine, makes it necessary to undertake a critical examination of the method. Care-providing physicians should question their patients about other unconventional medical diagnostic procedures to which they have been submitted, and inform them about the dubious nature of non-evaluated methods.


Assuntos
Terapias Complementares , Processamento de Sinais Assistido por Computador/instrumentação , Termografia/instrumentação , Regulação da Temperatura Corporal/fisiologia , Humanos , Microcomputadores , Valor Preditivo dos Testes , Temperatura Cutânea/fisiologia
17.
J Basic Microbiol ; 31(2): 135-40, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1880715

RESUMO

Three human and three murine monoclonal antibodies were tested for their reactivity to tetanus toxin and toxoid and used to establish an enzyme immunoassay specific for tetanus toxin. The dissociation constants of the monoclonal antibodies were between 3.91 x 10(-9) and 8.48 x 10(-12). Two human monoclonal antibodies recognized conformation determinants on the toxin, whereas the others reacted to the heavy chain. Only a combination of antibodies of the two species allowed the development of an enzyme immunoassay for the detection of tetanus toxin with a lower detection limit of 1.2 micrograms/l.


Assuntos
Anticorpos Monoclonais , Toxina Tetânica/análise , Animais , Ensaio de Imunoadsorção Enzimática , Humanos , Camundongos
18.
J Clin Chem Clin Biochem ; 28(10): 669-75, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1704407

RESUMO

alpha 1-Microglobulin was purified from urine to a purity of 97.7% in a yield of 25.8%, and was used to produce antibodies in sheep. These antibodies, purified by affinity chromatography, were used to develop a rapid one-step and a two-step immunoenzymometric assay (IEMA). The equilibrium in the reaction between solid phase-adsorbed antibodies and antigen and between the antigen and enzyme-labelled antibodies was attained within 30 and 100 min, respectively. The one-step IEMA permits a good differentiation of low alpha 1-microglobulin concentrations after 30 min reaction time. Its detection limit is 0.35 micrograms/l, and its measurement range is between 0.5 and 100 micrograms/l. The IEMA correlates well with radial immunodiffusion (r = 0.973). The mean alpha 1-microglobulin serum concentration in women is insignificantly lower (33.2 mg/l) than in men (36.1 mg/l). In both sexes the alpha 1-microglobulin concentration increases with age. HIV-infected symptomless men have a significantly lower (15.9 mg/l) alpha 1-microglobulin concentration in serum than normal persons, whereas in AIDS patients it is significantly higher (45.5 mg/l).


Assuntos
Síndrome da Imunodeficiência Adquirida/sangue , alfa-Globulinas/análise , Infecções por HIV/sangue , HIV-1 , Inibidores de Proteases/sangue , Adulto , alfa-Globulinas/isolamento & purificação , Cromatografia de Afinidade , Cromatografia em Gel , Cromatografia por Troca Iônica , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Valores de Referência , Análise de Regressão
19.
Arch Geschwulstforsch ; 60(5): 349-55, 1990.
Artigo em Alemão | MEDLINE | ID: mdl-2241511

RESUMO

On rats hypothermia of 22 to 20 degrees C and rewarming to normal body temperature leads to an amplification of the hyperglycemic tumor acidification. Mechanism and significance of this effect are discussed.


Assuntos
Glicemia/fisiologia , Carcinossarcoma/fisiopatologia , Hipotermia Induzida , Animais , Concentração de Íons de Hidrogênio , Masculino , Ratos , Ratos Endogâmicos
20.
J Basic Microbiol ; 30(10): 759-68, 1990.
Artigo em Alemão | MEDLINE | ID: mdl-2090805

RESUMO

For mass cultivation of Candida albicans (serotype A), a fermenter dialysis culture technique is described and compared with shaking culture and fermenter batch culture techniques. Important growth parameters such as yeast dry weight and viable cell counts demonstrate the advantage of the fermenter dialysis culture. Mannan, the major antigen from Candida albicans prepared by phenol-water extraction followed by gel chromatography was tested with the monoclonal IgM antibody H5.


Assuntos
Candida albicans/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Meios de Cultura , Fermentação
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