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1.
Pharmeur Bio Sci Notes ; 2021: 1-25, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33734082

RESUMO

Following a decision of the European Pharmacopoeia (Ph. Eur.) Commission, the Traditional Chinese Medicines (TCM) Working Party started a pilot phase to examine the suitability of a high-performance thin-layer chromatography (HPTLC) minimum content test as an alternative to the classical assay in TCM monographs. This approach was evaluated with two TCM herbal drugs: Fritillaria thunbergii bulbs (FTB) and Corydalis rhizome (CYR). Firstly, the existing HPTLC methods were optimised for both drugs. The new methods were applied to the evaluation of multiple samples, and acceptance criteria for the identification, following Ph. Eur. chapter 2.8.25. High-performance thin-layer chromatography of herbal drugs and herbal drug preparations, were set. The HPTLC test for minimum content of markers was then developed and validated. In this test, the intensity of the marker zone in the fingerprint of the sample is compared to the corresponding zone in the reference solution, which has a concentration giving an intensity equivalent to the acceptance criterion. This test gives a pass or fail result rather than a content and can be performed visually (on the images) or by software (using peak profiles from images; PPI). Reproducibility of the HPTLC methods was evaluated in a collaborative trial including six laboratories. In summary, results for FTB from five laboratories were in agreement. The remaining laboratory did not pass the identification of the samples. For CYR, all laboratories presented the same results for identification. In the test for minimum content, one borderline sample passed in four laboratories and failed in two. All laboratories reached similar conclusions for the other seven samples. The HPTLC methods proposed offer a simplified approach to evaluating identity and minimum content of TCM drugs in a single analysis.


Assuntos
Fritillaria , Preparações Farmacêuticas , Cromatografia em Camada Fina , Medicina Tradicional Chinesa , Reprodutibilidade dos Testes
2.
Occup Med (Lond) ; 68(4): 246-254, 2018 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-29590486

RESUMO

Background: The ageing of the US labour force highlights the need to examine older adults' physical and psychological ability to work, under varying levels of occupational burnout. Aims: To examine how age and burnout interact in predicting physical and psychological work ability. Methods: Using a cohort of actively working nurses, we assessed factors on the Work Ability Index at 12-month follow-up and determined how these were related to age and exhaustion-related burnout at baseline. Results: The study group consisted of 402 nurses aged 25-67 (mean = 41.7). Results indicated age by burnout interactions in which decrements in physical work ability with greater age were observed at all but the lowest level of burnout (1.5 SD below mean: ß = -0.14, 95% CI -0.36, 0.07; 1 SD below: ß = -0.23, 95% CI -0.39, -0.06; mean: ß = -0.39, 95% CI -0.50, -0.29; 1 SD above: ß = -0.56, 95% CI -0.70, -0.42; 1.5 SD above: ß = -0.64, 95% CI -0.83, -0.46). In contrast, we observed decrements in psychological work ability with age at higher levels of burnout only (1 SD above: ß = -0.20, 95% CI -0.35, -0.05; 1.5 SD above: ß = -0.30, 95% CI -0.49, -0.11); at lower levels of burnout, older age was associated with improvements in this (1 SD below: ß = 0.19, 95% CI 0.03, 0.35; 1.5 SD below: ß = 0.29, 95% CI 0.08, 0.50). Conclusions: Findings indicated physical and psychological dimensions of work ability that differed by age and occupational burnout. This emphasizes the need for interventions to reduce burnout and to address age-related strengths and vulnerabilities relating to physical and psychological work ability.


Assuntos
Fatores Etários , Esgotamento Profissional/etiologia , Programas de Rastreamento/estatística & dados numéricos , Enfermeiras e Enfermeiros/psicologia , Estresse Ocupacional/complicações , Avaliação da Capacidade de Trabalho , Adulto , Idoso , Esgotamento Profissional/psicologia , Estudos de Coortes , Escolaridade , Feminino , Humanos , Masculino , Programas de Rastreamento/métodos , Programas de Rastreamento/normas , Pessoa de Meia-Idade , Enfermeiras e Enfermeiros/estatística & dados numéricos , Estresse Ocupacional/psicologia , Sudeste dos Estados Unidos , Local de Trabalho/psicologia , Local de Trabalho/normas , Local de Trabalho/estatística & dados numéricos
3.
Artigo em Alemão | MEDLINE | ID: mdl-21800244

RESUMO

Evidence for the effectiveness of measures aiming to reduce psychosocial work stress is sporadic. This is contradictory to the requirement identified by the German Social Security Code (SGB VII) that interventions constitute the most important method of maintaining and improving employees' health. Reasons for this can be seen in the complexity of the subject and methodological issues concerning scientific standards. In addition, agreed quality standards are nonexistent for the evaluation of intervention measures. For this reason, a synopsis of existing audit and evaluation schemes was performed, thus, resulting in refined and adapted quality standards for intervention measures aiming to reduce psychosocial work stress. The quality criteria presented in this paper comprise aims, effectiveness, and facilitators, each being composed of several indicators. The criteria are designed as quality indicators which translate the outcome of an evaluation into quality figures. The process is transparent and offers a rational basis for communication, planning, and decision-making in health promotion.


Assuntos
Promoção da Saúde/organização & administração , Doenças Profissionais/prevenção & controle , Doenças Profissionais/psicologia , Saúde Ocupacional/normas , Estresse Psicológico/prevenção & controle , Estresse Psicológico/psicologia , Carga de Trabalho/classificação , Carga de Trabalho/psicologia , Prática Clínica Baseada em Evidências , Alemanha , Promoção da Saúde/métodos , Promoção da Saúde/normas , Humanos , Auditoria Administrativa , Objetivos Organizacionais , Avaliação de Programas e Projetos de Saúde , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Indicadores de Qualidade em Assistência à Saúde , Previdência Social , Estresse Psicológico/complicações , Carga de Trabalho/normas
4.
Occup Med (Lond) ; 60(7): 517-24, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20573840

RESUMO

BACKGROUND: The Work Ability Index (WAI) is a well-established instrument to measure work ability. However, the dimensionality of the WAI remains controversial. AIMS: To identify the dimensionality of the WAI and to investigate dependencies of factors and subscales. METHODS: The sample analysed in this study consisted of 371 subjects of different occupational groups (teachers, office workers, nursery school teachers and managers). The WAI was measured for all subgroups. Psychometric characteristics of the WAI were investigated using factor analyses with different numbers and different patterns of dependency among the factors. Chi-square analysis and the Comparative Fit Index were used to statistically assess fit quality. RESULTS: The group of managers had to be excluded from the analysis as their results were probably overoptimistic due to reporting bias; thus, 324 subjects entered. The one-factor model and an orthogonal two-factor model did not fit the observed correlational structures. A satisfactory fit was obtained using a two-dimensional model with correlated factors. These factors could be interpreted as subjectively estimated work ability and objective health status. Only five of seven items of the WAI could be related unambiguously to one of both factors. CONCLUSIONS: From our study, we conclude that using only the total score of the WAI is not adequate for population analysis of and assessment of work ability to individuals. Instead, the two-dimensional structure of the instrument must be taken into account.


Assuntos
Nível de Saúde , Modelos Estatísticos , Inquéritos e Questionários , Avaliação da Capacidade de Trabalho , Adolescente , Adulto , Interpretação Estatística de Dados , Análise Fatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria , Adulto Jovem
5.
J Exp Biol ; 204(Pt 20): 3531-45, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11707502

RESUMO

The oviposition of female locusts requires longitudinal muscles to tolerate remarkable lengthening. Whether this ability together with concomitant properties develops during maturation or is present throughout life was investigated. The properties of the locust abdominal muscles involved in oviposition behaviour were investigated with respect to their maturation, segment- and gender-specificity and regulation by juvenile hormone (JH). Muscles from the sixth abdominal segment (an oviposition segment) of mature females (>18 days old) were able to tolerate large extensions (>8 mm). At this length, muscles were still able to generate considerable neurally evoked twitch tension. In contrast, muscle fibres from females less than 5 days old did not tolerate extension of more than 4 mm. At this length, tension generation was negligible. The maximum tension generated at different stimulus frequencies was significantly higher in muscles of females more than 18 days old than in females less than 5 days old. Furthermore, the cross-sectional area of muscle fibres increased significantly during reproductive development. Current-clamp recordings from denervated muscle fibres of females more than 18 days old revealed their ability to generate overshooting action potentials. The potentials were tetrodotoxin (TTX)-insensitive (0.5 micromol l(-1) TTX), but were blocked by Cd(2+) (50 micromol l(-1)) or nifedipine (50 micromol l(-1)), which suggests the involvement of L-type Ca(2+) channels. Action potentials recorded from females less than 5 days old differed considerably in amplitude and shape from those recorded from females more than 18 days old, suggesting their maturation during the first 2 weeks of adult life. Inactivation of the corpora allata (CA) by precocene inhibited the maturation of these muscle properties, whereas injection of JH into precocene-treated females reversed this effect. Homologous muscles from the third abdominal segment (a non-oviposition segment, M169) and muscles from males (M214) revealed no comparable changes, although some minor changes occurred during reproductive development. The results suggest a gender- and segment-specific maturation of muscle properties that is related to reproductive behaviour and controlled by JH.


Assuntos
Gafanhotos/crescimento & desenvolvimento , Hormônios Juvenis/farmacologia , Desenvolvimento Muscular , Músculos/fisiologia , Músculos Abdominais/efeitos dos fármacos , Músculos Abdominais/crescimento & desenvolvimento , Músculos Abdominais/fisiologia , Potenciais de Ação , Animais , Canais de Cálcio Tipo L/fisiologia , Feminino , Gafanhotos/fisiologia , Masculino , Denervação Muscular , Fibras Musculares Esqueléticas/fisiologia , Músculos/efeitos dos fármacos , Oviposição/fisiologia , Caracteres Sexuais
6.
Biol Reprod ; 65(5): 1542-7, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11673273

RESUMO

We evaluated the effects of follicular exposure in vitro to either of two mutually exclusive isoforms of FSH (least acidic and acid) on the subsequent capacity of oocytes for embryonic development. The effects of dose and follicle culture duration were examined. At the threshold dose (that required to produce antra) and at one subthreshold dose, the major difference between the two isoform fractions was the timing and effectiveness of acquisition of two-cell embryonic developmental capacity. With the least-acidic fraction, the highest rate of two-cell development (approximately 80%) occurred after 3 days of follicle culture only at the threshold dose (2.5 ng/ml). With the acid fraction, the highest two-cell rate (approximately 60%) occurred after 5 days of culture but at equivalent rates over a range of doses between 10 ng/ml and 100 ng/ml (threshold dose was 50 ng/ml). At threshold dose or below, the capacity for two-cell embryo production appeared not to be influenced by antral status for either isoform. At above threshold doses, the least-acidic fraction induced an increasing proportion of antral follicles with increasing dose, but this increase was associated with a progressive decrease in embryo production. This relationship was more extreme after longer culture and was due to degeneration of the cumulus-oocyte complex associated with apparently increased differentiation of the mural granulosa cells. The acid fraction was by comparison less bioactive and insensitive to overdosing. The broader isoform mix of the unfractionated FSH provided a measure of protection against overdosing characteristic of the acid fraction while retaining the capacity of the least-acidic fraction to induce antral formation at a low dose.


Assuntos
Desenvolvimento Embrionário e Fetal , Hormônio Foliculoestimulante/química , Hormônio Foliculoestimulante/farmacologia , Oócitos/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Isoformas de Proteínas , Animais , Técnicas de Cultura , Relação Dose-Resposta a Droga , Feminino , Fertilização in vitro , Hormônio Foliculoestimulante/administração & dosagem , Ponto Isoelétrico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Oócitos/fisiologia , Folículo Ovariano/citologia
7.
Endocrinology ; 142(11): 4891-9, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11606457

RESUMO

Although ovarian follicle growth is under the influence of many growth factors and hormones of which FSH remains one of the most prominent regulators. Therefore, factors affecting the sensitivity of ovarian follicles to FSH are also important for follicle growth. The aim of the present study was to investigate whether anti-Müllerian hormone (AMH) has an inhibitory effect on follicle growth by decreasing the sensitivity of ovarian follicles to FSH. Furthermore, the combined action of AMH and FSH on ovarian follicle development was examined. Three different experiments were performed. Using an in vitro follicle culture system it was shown that FSH-stimulated preantral follicle growth is attenuated in the presence of AMH. This observation was confirmed by an in vivo experiment showing that in immature AMH-deficient females, more follicles start to grow under the influence of exogenous FSH than in their wild-type littermates. In a third experiment, examination of the follicle population of 4-month-old wild-type, FSH beta-, AMH-, and AMH-/FSH beta-deficient females revealed that loss of FSH expression has no impact on the number of primordial and preantral follicles, but the loss of inhibitory action of AMH on the recruitment of primordial follicles in AMH-deficient mice is increased in the absence of FSH. In conclusion, these studies show that AMH inhibits FSH-stimulated follicle growth in the mouse, suggesting that AMH is one of the factors determining the sensitivity of ovarian follicles for FSH and that AMH is a dominant regulator of early follicle growth.


Assuntos
Hormônio Foliculoestimulante/antagonistas & inibidores , Hormônio Foliculoestimulante/farmacologia , Glicoproteínas , Inibidores do Crescimento/fisiologia , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/fisiologia , Hormônios Testiculares/fisiologia , Animais , Hormônio Antimülleriano , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Foliculoestimulante/genética , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Inibidores do Crescimento/genética , Técnicas In Vitro , Inibinas/sangue , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout/genética , Tamanho do Órgão/efeitos dos fármacos , Folículo Ovariano/anatomia & histologia , Ovário/anatomia & histologia , Hormônios Testiculares/genética , Útero/anatomia & histologia
8.
Pharmacopsychiatry ; 34(2): 50-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11302564

RESUMO

Sleep disturbance and cognitive impairment are frequent complaints of depressed patients under standard antidepressant medication. Therefore, additional therapies are required which specifically focus on the improvement of these deficits without exerting major side effects. Ginkgo biloba extract (EGb) has been shown to improve cognitive abilities in elderly subjects and in patients with disorders of the dementia spectrum. Animal studies surmise that EGb may reduce CRH activity, which is substantially related to depressive mood and behavior, predominantly cognition and sleep. An open non-randomized pilot study has been conducted to investigate the effects of ginkgo biloba extract (EGb Li 1370) on cognitive performance and sleep regulation in depressed inpatients. 16 patients were treated with a trimipramine (T)-monotherapy (200 mg) for six weeks. In eight of the 16 patients, an adjunct EGb therapy (240 mg/d) was applied for four weeks after a baseline week, the other eight patients remained on trimipramine monotherapy (200 mg) during the entire study. Polysomnography, cognitive psychomotor performance and psychopathology were assessed at baseline, after short-term and long-term adjunct EGb treatment, and after one week of ginkgo discontinuation (at the respective evaluation times in the eight patients on T-monotherapy). This report focuses on the results of EGb on sleep EEG pattern. EGb significantly improved sleep pattern by an increase of sleep efficiency and a reduction of awakenings. In addition, sleep stage 1 and REM-density were reduced, while stage 2 was increased. Non-REM sleep, predominantly slow wave sleep in the first sleep cycle, was significantly enhanced compared to trimipramine monotherapy. Discontinuation of EGb reversed most of these effects. Based on the animal data, these results suggest that EGb may improve sleep continuity and enhance Non-REM sleep due to a weakening of tonic CRH-activity. The compensation of the deficient Non-REM component in depression by the EGb application may provide a new additional treatment strategy, especially in the treatment of the depressive syndrome with sleep disturbance.


Assuntos
Antidepressivos Tricíclicos/uso terapêutico , Transtorno Depressivo/tratamento farmacológico , Ginkgo biloba/uso terapêutico , Fitoterapia , Plantas Medicinais , Polissonografia/efeitos dos fármacos , Trimipramina/uso terapêutico , Adulto , Transtorno Depressivo/psicologia , Feminino , Ginkgo biloba/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Extratos Vegetais/uso terapêutico , Sono/efeitos dos fármacos , Sono REM/efeitos dos fármacos , Síndrome de Abstinência a Substâncias/prevenção & controle
9.
Steroids ; 65(10-11): 733-40, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11108884

RESUMO

Org 31710 and Org 33628 are two highly selective progesterone receptor modulators (PRMs) with respect to their anti-progestational and anti-glucocorticoid activity. The compounds have been studied both in vitro and in vivo. Org 33628 has approximately four times stronger anti-progestational activity in vitro than does Org 31710, and in rats it is about 15 times more potent in the pregnancy interruption test. Two main indications for the use of PRMs are breast cancer and fertility regulation. The effects of both Org 31710 and Org 33628 were tested in relevant models for these indications. The effects of the two compounds on breast tumor development were assessed and in rats using the DMBA model. Their potency in menses induction was tested in monkeys on a 4-day regimen in the luteal phase, and after a single dose at day 21 of the normal cycle, and under a continuous progestin treatment using desogestrel. The compounds were also tested alone in a continuous low-dose regimen. The effects on follicular development and ovulation were determined by measuring estradiol and progesterone levels. Cycle control was monitored by daily vaginal swabs. In the DMBA model, Org 31710 at oral doses of 0.8, 2.0, and 5.0 mg/kg showed a clear dose-related reduction in tumor load. With the two highest doses, an even lower tumor load was seen after a 3-week treatment period compared to the tumor load at the start of treatment. Org 33628 showed a similar efficacy as Org 31710 at a dose of 2.0 mg/kg. RU 486 after oral treatment was two times less potent in this model than Org 31710 and Org 33628. The efficacy of menses induction using the 4-day regimen is dependent on the time of administration relative to the progesterone peak in the luteal phase. The highest efficacy is achieved in the descending part of the peak, at which a 100% success rate is found with a dose of 1 mg/kg of either Org 31710 or Org 33628. In Cynomolgus monkeys, at a single dose of 15 mg/kg of Org 31710 or Org 33628 in the luteal phase, menses induction was achieved only in 60% of the treatment cycles. Surprisingly menses induction can be achieved with a single dose that is about a ten-times lower when the monkeys are treated continuously with desogestrel. Cycle control is better at low than at high doses of antiprogestin in combination with daily dosing of 4 microg/kg desogestrel. Despite the difference in receptor affinity, no difference between Org 31710 and Org 33628 was found in menses induction. In the continuous low-dose (1 mg/kg) regimen with the PRMs, follicular development occurs normally while ovulation is inhibited. Ovulation is resumed shortly after stopping treatment, and a normal menses occurs after the first progesterone peak. Both compounds may be interesting options for the prevention and treatment of breast cancer and for fertility control.


Assuntos
Endométrio/efeitos dos fármacos , Estrenos/farmacologia , Furanos/farmacologia , Animais , Neoplasias da Mama/tratamento farmacológico , Divisão Celular/efeitos dos fármacos , Tamanho Celular/efeitos dos fármacos , Anticoncepcionais Femininos/farmacologia , Anticoncepcionais Femininos/uso terapêutico , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Endométrio/citologia , Estrenos/uso terapêutico , Feminino , Furanos/uso terapêutico , Antagonistas de Hormônios/farmacologia , Antagonistas de Hormônios/uso terapêutico , Humanos , Macaca fascicularis , Menstruação/efeitos dos fármacos , Indutores da Menstruação/farmacologia , Neoplasias Experimentais/tratamento farmacológico , Ratos , Receptores de Progesterona/agonistas , Receptores de Progesterona/antagonistas & inibidores , Relação Estrutura-Atividade , Células Tumorais Cultivadas
10.
J Comp Neurol ; 426(3): 391-405, 2000 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-10992245

RESUMO

During metamorphosis of the moth, Manduca sexta, the larval legs degenerate and are replaced by adult legs with a diverse array of new sensory organs. The majority of the larval sensory neurons degenerate but some hair sensilla and chordotonal organ sensory neurons survive metamorphosis (Consoulas [2000] J. Comp. Neurol. 419:154-174). In the present study nerve-tracing techniques, birth-date labeling (5-bromodeoxyuridine), and electrophysiology were used to describe the remodeling of the femoral chordotonal organ (FCO) in the prothoracic legs. The larval FCO is composed of two scoloparia, which are associated with separate apodemes. At the onset of metamorphosis, some of the 13 larval neurons degenerate, together with the larval FCO apodemes. The remaining larval FCO sensory neurons persist in the imaginal leg to become the precursors of the adult femoral and tibial chordotonal organs respectively. Early in the pupal stage, 45 to 60 new sensory neurons are generated de novo and become associated with 6 persistent larval neurons in the imaginal femur to compose the adult FCO. Two clusters of persistent and new neurons are enclosed into two scoloparia with short apodemes that eventually become fused. In both larval and adult stages, the FCO contains units that respond phasically and others that respond tonically to femorotibial movements. Nerve activity from the FCO neurons can be recorded continuously during the remodeling of the organ. A persistent leg flexor motoneuron receives inputs from the FCO sensory neurons in both larval and adult stages, offering the opportunity to investigate the remodeling of the neural circuits underlying the proprioceptive control of the femorotibial joint.


Assuntos
Manduca/crescimento & desenvolvimento , Metamorfose Biológica/fisiologia , Órgãos dos Sentidos/crescimento & desenvolvimento , Vias Aferentes/fisiologia , Animais , Eletrofisiologia , Extremidades/crescimento & desenvolvimento , Extremidades/inervação , Larva/fisiologia , Neurônios Motores/fisiologia , Degeneração Neural , Neurônios Aferentes/fisiologia , Órgãos dos Sentidos/inervação , Sinapses/fisiologia
11.
J Comp Physiol A ; 186(4): 327-36, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10798721

RESUMO

Persistent leg motoneurons of the moth Manduca sexta were investigated in larval and adult animals to compare their dendritic structures, intrinsic electrical properties and pattern of target innervation. The study focused on two identified motoneurons of the prothoracic leg. Despite the complete remodeling of leg muscles, the motoneurons innervated pretarsal flexor muscles in both larval and adult legs. Similarly, although the central dendrites regress and regrow, the branching pattern was similar with the exception of a prominent midline branch that was not present in the adult stage. The intrinsic electrical properties of the motoneurons differed between larval and adult stages. Larval motoneurons had significantly higher membrane input resistances and more depolarized resting membrane potentials than did motoneurons in pharate adults or adults. In all stages, one motoneuron had a low maximal firing frequency, whereas the second motoneuron, which innervated the other half of the muscle, had a high maximum firing frequency. Although the two motoneurons continued to innervate the same halves of the target muscle, their relative effects on muscular contraction were reversed during metamorphosis along with concomitant changes in intrinsic properties. Pretarsal flexor motoneurons in pharate adults (just prior to emergence) displayed properties similar to those in emerged adults.


Assuntos
Manduca/crescimento & desenvolvimento , Manduca/fisiologia , Metamorfose Biológica/fisiologia , Neurônios Motores/fisiologia , Neurônios Motores/ultraestrutura , Fatores Etários , Animais , Impedância Elétrica , Estimulação Elétrica , Eletrofisiologia , Extremidades/inervação , Extremidades/fisiologia , Larva/fisiologia , Manduca/anatomia & histologia , Potenciais da Membrana/fisiologia , Movimento/fisiologia , Fibras Musculares Esqueléticas/fisiologia
12.
J Insect Physiol ; 46(1): 69-80, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12770260

RESUMO

The oviposition of female locusts is a complex behaviour that includes a dramatic extension of the abdomen. The role of internal pressure during oviposition was investigated by monitoring the intra-tracheal pressure and the activity of selected longitudinal muscles, while movements of the abdomen were visualised with a video imaging system. Locust oviposition consists of a sequence of four distinct phases: (i) probing the substrate and digging without elongation of the abdomen, (ii) longitudinal extension of the abdomen up to four times its normal length, (iii) laying packages of eggs while (iv) gradually withdrawing the abdomen. During extension, neurograms and myograms of selected longitudinal muscles revealed a decreased level of activity. When the abdomen retracted to its normal length, muscle activity re-appeared. In phases two and three, rising internal pressure prevented the abdomen from slipping back when the valves released their lateral grip from the substrate. Locking the genital segments in the hole by relative bending kept the abdomen in place when producing foam or laying eggs. Intra-abdominal pressure, therefore, is not the main cause of abdominal extension, but rather maintains extension when no mechanical locking in the hole prevents the abdomen from elastic retraction.

13.
Biol Reprod ; 61(2): 503-11, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10411533

RESUMO

To investigate ovulation, an in vitro model with cultured mouse follicles was developed and compared with an in vivo ovulation model. In this model, secondary follicles were grown in vitro with immature mouse serum (5%) and recombinant human FSH. Addition of ascorbic acid and selenium to the medium increased follicular survival (from 29% to 86%) and resulted in the development of healthy preovulatory follicles (> 400 microm) producing estradiol. Depending on the starting size of the follicles, the preovulatory stage was reached after 4-6 days. The ovulatory response to hCG was maximal in follicles exceeding a diameter of 400 microm. The in vitro-ovulated oocytes could be fertilized and were able to develop to the blastocyst stage. Ovulation induced by hCG was dose dependent, reaching a maximum of 80% at 1 IU/ml. Concomitantly, progesterone production increased from 3.6 +/- 0.5 to 29 +/- 2 ng/ml. Both in vivo and in vitro, hCG induced expression of the progesterone receptor and the prostaglandin endoperoxide synthase-2 (PGS-2) gene within 3 h. Ovulation could be completely blocked with the anti-progestogen Org-31710 and partially (50%) with the PGS inhibitor indomethacin in vitro and in vivo. Org-31710 and indomethacin did not affect progesterone production. In summary, a physiologically relevant in vitro ovulation model of cultured mouse follicles that can be used to study the process of follicular rupture has been developed.


Assuntos
Folículo Ovariano/crescimento & desenvolvimento , Ovulação , Animais , Ácido Ascórbico/farmacologia , Gonadotropina Coriônica/farmacologia , Técnicas de Cultura , Ciclo-Oxigenase 2 , Estrenos/farmacologia , Feminino , Furanos/farmacologia , Antagonistas de Hormônios/farmacologia , Humanos , Indometacina/farmacologia , Camundongos , Folículo Ovariano/efeitos dos fármacos , Indução da Ovulação , Prostaglandina-Endoperóxido Sintases/metabolismo , Selênio/farmacologia
14.
Endocrinology ; 140(3): 1236-44, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10067849

RESUMO

Transgenic mice with deletion of the GDF-9 (growth differentiation factor-9) gene are characterized by the arrest of ovarian follicle development at the primary stage. Based on the hypothesis that GDF-9 is important for early follicle development, we isolated rat GDF-9 complementary DNA (cDNA) and generated recombinant GDF-9 protein to study its physiological role. Using bacteria-derived GDF-9-glutathione S-transferase (GST) fusion protein, specific antibodies to the mature form of GDF-9 was generated. Immunohistochemical staining of ovarian sections indicated the localization of GDF-9 protein in the oocyte of primary, secondary and preantral follicles, whereas immunoblotting demonstrated the secretion of GDF-9 by mammalian cells transfected with GDF-9 cDNAs. Recombinant GDF-9 was shown to be an N-glycosylated protein capable of stimulating early follicle development. Growth of preantral follicles isolated from immature rats was enhanced by treatment with either GDF-9 or FSH whereas the combined treatment showed an additive effect. In addition, treatment with GDF-9, like forskolin, also stimulated inhibin-alpha content in explants of neonatal ovaries. In contrast, the stimulatory effects of GDF-9 were not mimicked by amino-terminal tagged GDF-9 that was apparently not bioactive. Thus, the present study demonstrates the important role of GDF-9 in early follicle growth and differentiation. The availability of recombinant bioactive GDF-9 allows future studies on the physiological role of GDF-9 in ovarian development in vivo.


Assuntos
GMP Cíclico/análogos & derivados , Substâncias de Crescimento/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular , Folículo Ovariano/efeitos dos fármacos , Fator de Crescimento Transformador beta , Sequência de Aminoácidos , Animais , Proteína Morfogenética Óssea 15 , Diferenciação Celular/efeitos dos fármacos , Meios de Cultura Livres de Soro , GMP Cíclico/farmacologia , Feminino , Fator 9 de Diferenciação de Crescimento , Humanos , Camundongos , Dados de Sequência Molecular , Folículo Ovariano/citologia , Folículo Ovariano/crescimento & desenvolvimento , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/farmacologia , Homologia de Sequência de Aminoácidos
15.
J Pharm Biomed Anal ; 18(1-2): 1-14, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9863938

RESUMO

Monographs of the European Pharmacopoeia describe in the LC-test for related substances usually a system suitability test in order to ensure the adequate separation of impurities. Since the reference substances required are often not available a recent approach to avoid this problem is the generation of the required impurity by 'in situ degradation' of the active principle. This paper describes some typical applications of this technique as well as recent examples, such as the controlled degradation of cefalotin sodium, imipenem and spiramycin.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia/métodos , Contaminação de Medicamentos , Farmacopeias como Assunto/normas , Cefalotina/análise , Hidrólise , Imipenem/análise , Oxirredução , Espiramicina/análise
16.
Mem Cognit ; 26(6): 1292-303, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9847552

RESUMO

In three experiments, we investigated how associative word-word priming effects in German depend on different types of syntactic context in which the related words are embedded. The associative relation always concerned a verb as prime and a noun as target. Prime word and target word were embedded in visually presented strings of words that formed either a correct sentence, a scrambled list of words, or a sentence in which the target noun and the preceding definite article disagreed in syntactic gender. In contrast to previous studies (O'Seaghdha, 1989; Simpson, Peterson, Casteel, & Burgess, 1989), associative priming effects were not only obtained in correct sentences but also in scrambled word lists. Associative priming, however, was not obtained when the definite article and the target noun disagreed in syntactic gender. The latter finding suggests that a rather local violation of syntactic coherence reduces or eliminates word-word priming effects. The results are discussed in the context of related work on the effect of gender dis-/agreement between a syntactic context and a target noun.


Assuntos
Rememoração Mental , Aprendizagem por Associação de Pares , Leitura , Semântica , Adulto , Atenção , Feminino , Humanos , Masculino , Psicolinguística
17.
Biol Reprod ; 59(4): 854-61, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9746735

RESUMO

The effects of three isoforms derived from recombinant human FSH on ovarian follicle development in vitro were characterized for the first time. The three subfractions comprised discrete pI ranges of 3. 6-4.6 (acid), 4.5-5.0 (mid), and 5.0-5.6 (least acidic). Follicular growth, estradiol secretion, and antral formation were assessed for each fraction of isoforms in a range of concentrations over a 5-day culture period. Least acidic FSH produced, at and above 1.5 ng/ml, a high percentage of follicles growing above the size threshold necessary for antral formation, whereas mid and acid FSH induced similar growth only at higher concentrations (7.5 ng/ml and 50 ng/ml, respectively). Least acidic FSH specifically induced the most rapid growth of follicles during preantral development. Acid FSH at all concentrations stimulated estradiol-17ss secretion later during culture and antral formation in a lower proportion of follicles than did least acidic and mid FSH. It can be concluded 1) that the least acidic isoform induced fastest preantral growth, producing the largest antral follicles at the lowest dose of all three fractions and 2) that the less and mid acidic isoforms had more impact on stimulation of estradiol production and antral formation than the acid isoform.


Assuntos
Hormônio Foliculoestimulante/química , Hormônio Foliculoestimulante/farmacologia , Folículo Ovariano/crescimento & desenvolvimento , Animais , Meios de Cultura , Estradiol/metabolismo , Feminino , Células da Granulosa/efeitos dos fármacos , Humanos , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Folículo Ovariano/citologia , Folículo Ovariano/efeitos dos fármacos , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia
18.
Eur J Biochem ; 253(1): 354-6, 1998 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9578495

RESUMO

Several studies indicate that in human choriogonadotropin the N-linked oligosaccharide at position 52 of the alpha-subunit is important for bioactivity. We have generated choriogonadotropin mutants in which the alpha52 glycosylation site is removed and the alpha and beta subunits are covalently linked by intersubunit disulfide bonds. These mutants display wild-type receptor binding and bioactivity. Furthermore, we show that removal of the alpha52 sugar leads to instability of heterodimeric choriogonadotropin. Therefore, we conclude that the alpha52 oligosaccharide of choriogonadotropin is not involved in signal transduction, but in the stability of the heterodimer.


Assuntos
Gonadotropina Coriônica/química , Gonadotropina Coriônica/farmacologia , Animais , Células CHO , Gonadotropina Coriônica/genética , Cricetinae , Dissulfetos/química , Estabilidade de Medicamentos , Glicosilação , Humanos , Técnicas In Vitro , Mutagênese Sítio-Dirigida , Receptores do LH/efeitos dos fármacos , Receptores do LH/genética , Transdução de Sinais , Temperatura
19.
Scand J Gastroenterol ; 32(11): 1147-51, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9399397

RESUMO

BACKGROUND: Changes in the p53 gene product can be immunogenic and enable the formation of p53 serum antibodies (p53ab), detectable in patients with different cancer types. So far, there have been no reports describing the detectability of p53ab in gastric cancer patients. METHODS: We investigated the presence of p53ab and their clinical relevance in a cohort of 74 gastric cancer patients, using an enzyme-linked immunosorbent assay system. RESULTS: In our investigation 20.3% of all patients (15 of 74) and 46.9% of the patients with immunohistochemically (IHC) p53-positive tumors (15 of 32) showed detectable p53ab in serum. All p53ab-positive patients had IHC p53-positive tumors. We have found a significant correlation of p53ab with a higher tumor stage (P = 0.002) and also with a poor prognosis of survival (P = 0.04). CONCLUSION: We have shown that in gastric cancer patients p53ab are also detectable and that p53ab positivity is a predictor of an unfavorable prognosis.


Assuntos
Autoanticorpos/sangue , Biomarcadores Tumorais/sangue , Neoplasias Gástricas/sangue , Neoplasias Gástricas/diagnóstico , Proteína Supressora de Tumor p53/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias/normas , Prognóstico , Sensibilidade e Especificidade , Neoplasias Gástricas/patologia
20.
Arch Phys Med Rehabil ; 78(6): 615-20, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9196469

RESUMO

OBJECTIVE: To continue and expand determination of the reliability, validity, and sensitivity to change of the Arm Motor Ability Test (AMAT), an instrument for assessing deficits in activities of daily living (ADL). DESIGN: The AMAT was administered twice to patients, with an interest interval of either 1 or 2 weeks, by one of two examiners assigned to patients in counterbalanced order. Patients' interest intervals and scores on the arm portion of the Motricity Index was unknown to the raters. SETTING: A referral inpatient neurological rehabilitation center. PATIENTS: Thirty-three subacute stroke inpatients with moderate to mild upper extremity motor deficit: median Motricity-Index-Arm score = 89, median chronicity = 43d, median age = 66yr; 12 were women. MAIN OUTCOME MEASURE AND RESULTS: The AMAT was developed in 1987, and interrater reliabilities at that time were found to range from .95 to .99. The present values for interrater reliability (2 scales) from videotaped test performance were: kappas = .68 to .77. Spearman correlations = .97 to .99. For performance time, interscorer reliability from videotaped test performance was .99. Homogeneities for the three AMAT measures for the total sample (Cronbach's alpha and split-half reliability) were .93 to .99. The test-retest reliabilities for the total sample were .93 to .99. The correlations to the Motricity-Index-Arm score were .45 to .61. The AMAT detected the difference in change occurring as a result of the passage of 1 versus 2 weeks in these subacute inpatients, presumably as a result of intensive therapy and/or spontaneous recovery, confirming the results of an earlier intervention study. CONCLUSION: The AMAT is an instrument with high interrater reliability, internal consistency, and sensitivity to change, as well as having satisfactory concurrent validity.


Assuntos
Atividades Cotidianas , Braço , Avaliação da Deficiência , Destreza Motora , Idoso , Braço/fisiologia , Transtornos Cerebrovasculares/reabilitação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Centros de Reabilitação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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