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Akosua N.J.A. de Groot Pieter W.J. van Dongen Tom B. Vree Tom K.A.B. Eskes 《European journal of obstetrics, gynecology, and reproductive biology》1995,60(2):101-107
Objective: To study the pharmacodynamic and pharmacokinetic properties of oral and intravenous methylergometrine upon uterine motility during menstruation. Study-design: Intra-uterine pressure was measured in six volunteers with a fluid-filled sponge-tipped catheter during menstruation. Methylergometrine was given orally (0.5 mg) or intravenously (0.2 mg) in a cross-over design. Results: After intravenous administration, a fast increase of the frequency of uterine contractions and basal tone occurred with a decrease of amplitude, lasting at least 30 min. Oral administration had a late and less marked effect on uterine motility. An intravenous dose administered 24 h after an oral dose had no effect on uterine motility. Pharmacokinetic data, such as the maximum plasma concentration (Cmax), the time at which Cmax is reached (tmax) and the half-life of absorption (t1/2abs) also demonstrated large individual variations after oral administration. Conclusion: Oral administration of methylergometrine had an unpredictable and late effect on uterine motility on the menstruating uterus, probably due to an unpredictable bioavailability, in contrast with the fast and predictable effect after intravenous administration. 相似文献
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Rolf W. Hartmann Martin Frotscher Dorothea Ledergerber Gerald A. Wchter Gertrud L. Grün Tom F. Sergejew 《Archiv der Pharmazie》1996,329(5):251-261
In search of potential drugs for the treatment of estrogen- and androgen-dependent cancer as well as the prophylaxis of metastases, tetralones, tetralins, and dihydronaphthalenes bearing a OCH3 substituent at the benzene nucleus and an imidazol-4-yl, imidazol-1-yl, or 1,2,4-triazol-1-yl substituent in 2-position were synthesized with and without C1-spacer between the rings (compounds 2 – 26 ). The compounds were tested in vitro for inhibition of the three target enzymes P450 arom (human placental microsomes), P450 17 (rat testicular microsomes), and P450 TxA2 (citrated human whole blood). To examine selectivity, some compounds were further tested in vitro for inhibition of P450 18 (bovine adrenal mitochondria), P450 see (bovine adrenal mitochondria) and corticoid formation (aldosterone, corticosterone; ACTH stimulated rat adrenal tissue). In vivo, selected compounds were examined in Sprague Dawley rats regarding P450 TxA2 inhibition, reduction of plasma testosterone concentration, antiuterotrophic activity (inhibition of the uterotrophic activity of androstenedione), reduction of plasma estradiol concentration (pregnant mares' serum gonadotropin-primed rats), and mammary tumor inhibiting activity (dimethylbenzanthracene-induced tumor; pre- and postmenopausal model). In the series of imidazol-4-yl compounds, which represent a novelty in the field of azole inhibitors of steroidogenic P450 enzymes, strong inhibitors of P450 arom and/or P450 17 were found: 7-OCH3-2-(imidazol-4-ylmethylene)-1-tetralone ( 4 ) and 7-OCH3-2-(imidazol-4-ylmethyl)-tetralin ( 12 ) are among the most potent inhibitors of P450 arom in vitro known so far. Compound 4 is a selective inhibitor, whereas 12 shows in addition strong inhibition of P450 17. In contrast to 12 , the 6-OCH3 derivative (compound 11 ) is a selective inhibitor of P450 17, being 50 times more potent than ketoconazole. Some imidazol-1-yl compounds show a marked inhibition of P450 TxA2: 2-(imidazol-1-ylmethyl)-1-tetralone ( 13 ) is a selective inhibitor of P450 TxA2, whereas 7-OCH3-2-(imidazol-1-ylmethyl)-tetralin ( 17 ) as well as 2-(imidazol-1-ylmethyl)-tetralin ( 16 ) and 7-OCH3-2-imidazol-1-yl-3,4-dihydronaphthalene ( 25 ) additionally show strong inhibition of P450 arom and P450 17. Regarding the other steroidogenic P450 enzymes as well as corticosterone formation, the compounds show only little inhibitory activity. Aldosterone formation, however, is inhibited at low concentrations. Nevertheless, 4 and 12 are more selective, i.e. inhibit aldosterone synthesis less than the well known inhibitor of P450 arom fadrozole. The compounds show activity in the aforementioned in vivo tests. 相似文献
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Melanie Inkster Alan Montgomery Peter Donnan Tom MacDonald Frank Sullivan Tom Fahey 《The British journal of general practice》2005,55(521):931-937
BACKGROUND: Studies show that 60-75% of treated patients with hypertension in general practice, still do not reach the recommended blood pressure targets of <150/90 mmHg. AIM: To investigate aspects of hypertension management in relation to sociodemographic variables, antihypertensive drug treatment, and organisational factors in primary care. DESIGN OF STUDY: Observational study over 3 years. SETTING: Eight general practices in Tayside, UK. METHOD: Participants were 560 randomly selected patients aged 40-79 years receiving treatment for hypertension. The outcome measurement was blood pressure control, expressed in binary form based on the British Hypertension Society audit standard of <150/90 mmHg. RESULTS: Of 536 eligible patients, 261 (49%) were defined as having inadequate blood pressure control at the end of the study period. No significant associations were discovered with sex, age, deprivation score and comorbidity. In those patients with inadequate control, 30% had no modifications to their drug treatment during the study period. Blood pressure control at the end of the study period was not associated with number of antihypertensive drugs taken or number of antihypertensive drug modifications. The mean number of clinician contacts was 11 (standard deviation = 8), and mean continuity in primary care was high, although this was not associated with improved blood pressure control. A higher proportion of hypertension-related consultations were associated with increased odds of having inadequate blood pressure control. CONCLUSION: Achieving adequate blood pressure control continues to represent a substantial health problem in a significant proportion of the hypertensive population. Patient, physician and organisational elements play a role in ensuring effective delivery of hypertension care in the community. 相似文献
16.
Gary Coleman Tom A. Gardiner Ariel Boutaud Alan W. Stitt 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2007,245(4):581-587
Background A recombinant form of the α2(IV)NC1 domain of type IV collagen has been shown to have potent anti-angiogenic activity although
this peptide has not been studied in the context of proliferative retinopathies. In the current investigation we examined
the potential for α2(IV)NC1 to regulate retinal microvascular endothelial cell function using a range of in vitro and in vivo
assay systems.
Materials and methods α2(IV)NC1 at concentrations between 0.1 and 1 μg/ml was added to retinal microvascular endothelial cells (RMECs) followed
by assessment of cell attachment, proliferation and survival. This agent was also tested within a novel in vitro three-dimensional
retinal angiogenesis assay and the number of angiogenic sprouts quantified. α2(IV)NC1 was also delivered intra-vitreally to
mice with oxygen-induced proliferative retinopathy (OIR) and neovascularisation evaluated in comparison with vehicle-treated
controls.
Results RMECs treated with α2(IV)NC1 (0.1, 0.5 and 1 μg/ml) showed delayed attachment at 3 h post-seeding, although this deficit had
been restored at the 6-h time point. BrdU assay of DNA replication revealed that confluent RMECs treated with α2(IV)NC1 showed
no measurable response in comparison with vehicle-treated controls. By contrast, proliferation of sub-confluent RMECs was
significantly reduced by α2(IV)NC1 at 0.5 μg/ml (P<0.01). α2(IV)NC1 also induced apoptosis in RMECs and inhibited angiogenesis of pre-existing retinal vascular networks in
vitro (P<0.001). Intra-vitreal injection of α2(IV)NC1 in the OIR model significantly inhibited pre-retinal neovascularisation compared
with vehicle-treated controls (P<0.001).
Conclusion α2(IV)NC1 inhibits angiogenesis in the retinal microvasculature. This recombinant protein has potential for the treatment
of neovascularisation in proliferative retinopathies.
BioStratum Inc. did not sponsor this research in any way. None of the authors are paid consultants with this company. 相似文献
17.
Margaret Hogg Maxine Braithwaite Michael Bailey Tom Kotsimbos John W Wilson 《Journal of cystic fibrosis》2007,6(3):223-227
With increasing numbers of cystic fibrosis (CF) patients surviving to adulthood, issues related to vocation inevitably arise and warrant specific attention. We examined the percentage of participants with CF currently working and explored risk factors for work disability among adults with CF. METHOD: We recruited 50 consecutive patients from an adult cystic fibrosis service. Demographic, employment history, illness severity indicators and CF-attributed work disability factors were evaluated. Demographic risk factors for work disability using the illness severity measures of FEV(1), S-K score, CRDQ, and recent hospitalisation as independent variables were determined. RESULTS: Factorial analysis of a disability index (DI) indicated no dependency on FEV(1) or S-K score, but dependency on quality of life indices (p<0.05), age (p<0.05) and hospital admission rate (p<0.05). Hours worked per week were dependent on quality of life (p<0.01) (mastery of disease domain), fewer hospital admissions (p<0.01) and age (p<0.05). Sixty-eight percent of the sample reported that CF resulted in significant impediments to employment. However, few had sought vocational guidance (6%). CONCLUSION: Determinants of workforce participation shows that hours worked and perceived disability are more dependent on mastery of disease, age, and time in hospital, than on clinical severity scores. Health professionals may assist productivity through career counselling or tailored programs. 相似文献
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Emma L Wignall Jon M Dickson Paul Vaughan Tom F D Farrow Iain D Wilkinson Michael D Hunter Peter W R Woodruff 《Neuropsychopharmacology》2004,56(11):832-836
BACKGROUND: Previous structural magnetic resonance (MR) research in patients with posttraumatic stress disorder (PTSD) has found smaller hippocampal volumes in patients compared with control subjects. These studies have mostly involved subjects who have had PTSD for a number of years, such as war veterans or adult survivors of childhood abuse. Patients with recent-onset PTSD have rarely been investigated. To our knowledge only one other study has investigated such a group. The aim of this study was to compare hippocampal volumes of patients with recent onset PTSD and nontrauma-exposed control subjects. METHODS: Fifteen patients with PTSD, recruited from an accident and emergency department, were compared with 11, non-trauma-exposed, healthy control subjects. Patients underwent a structural MR scan soon after trauma (mean time = 158 +/- 41 days). Entire brain volumes, voxel size 1 x 1 x 1 mm, were acquired for each subject. Point counting and stereology were used to measure the hippocampal and amygdala volume of each subject. RESULTS: Right-sided hippocampal volume was significantly smaller in PTSD patients than control subjects after controlling for effects of whole brain volume and age. Neither left nor total hippocampal volume were significantly smaller in the PTSD group after correction. Whole brain volume was also found to be significantly smaller in patients. There were no differences in amygdala or white matter volumes between patients and control subjects. CONCLUSIONS: This result replicates previous findings of smaller hippocampal volumes in PTSD patients, but in an underinvestigated population, suggesting that either smaller hippocampal volume is a predisposing factor in the development of PTSD or that damage occurs within months of trauma, rather than a number of years. Either of these two hypotheses have significant implications for the treatment of PTSD. For instance, if it could be shown that screening for hippocampal volume may, in some cases, predict those likely to develop clinical PTSD. 相似文献
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