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Biomedical subjects

O Fischer

Publications and source records attributed to O Fischer.

At least 19 recordsLinked to original sources
PubMed2002

VEGF plasma pattern in ovulation induction: evidence for an episodic secretion and lack of immediate effect of hCG.

Vascular endothelial growth factor (VEGF) is a potent stimulator of vascular proliferation and permeability. Ovarian granulosa cells have been identified as a major source of the cytokine and r-hCG was able to stimulate VEGF mRNA expression in vitro. In this study we have investigated the immediate effect of ovulation induction with hCG on peripheral VEGF levels in 6 women with primary infertility enrolled in the IVF/ET program. The patients underwent a 24-hour continuous blood withdrawal with sampling intervals of 15 minutes starting from 5 hours before ovulation induction with 10.000 IU hCG. Ovulation induction with hCG had no significant immediate effect on mean peripheral VEGF levels. However, VEGF plasma levels did exhibit significant episodic fluctuations with rapid increases every 90-120 minutes without any relation to circulating hCG levels. Taken together, the results of this study suggest that VEGF is released episodically and that systemic VEGF levels are not acutely altered by ovulation induction with hCG.

17-alpha-Hydroxyprogesterone↗
PubMed2001

Diptera as vectors of mycobacterial infections in cattle and pigs.

Mycobacteria were isolated from 14 (4.5%) of 314 samples, containing 7791 adult Diptera, which were collected in the Czech Republic and Slovakia in 1997-2000. These flies were collected from three cattle herds with paratuberculosis, two pig herds with mycobacterial infections and one farm that kept both cattle and pigs and that did not have problems of mycobacterial infections. Mycobacterium intracellulare was isolated from Eristalis tenax Linnaeus (Diptera: Syrphidae) captured from a pig herd. Mycobacterium avium ssp. avium (serotype 8) was isolated from flies of the genera Drosophila Fallen (Diptera: Drosophilidae) and Musca Linnaeus (Diptera: Muscidae) originating from a pig herd. Mycobacterium spp. were isolated from Musca spp. and Mycobacterium fortuitum was isolated from dung flies of the genus Scatophaga Meigen (Diptera: Scatophagidae), Musca spp. and Stomoxys calcitrans Linnaeus (Diptera: Muscidae) captured in the same herd. Mycobacterium scrofulaceum was isolated from S. calcitrans from the farm with both cattle and pigs. Mycobacterium avium ssp. paratuberculosis was isolated from Scatophaga spp. collected from pastures grazed by one of the cattle herds and from Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae) and Lucilia caesar Linnaeus (Diptera: Calliphoridae) captured in a slaughterhouse, where cattle infected with paratuberculosis were slaughtered. Mycobacterium phlei was isolated from flies of the genus Lucilia captured at a waste bin. These data indicate that mycobacteria may be spread by adult flies that have been in contact with material contaminated with these pathogens.

Animals↗
PubMed2001

Peripheral levels of vascular endothelial growth factor (VEGF) are higher in gonadotropin stimulated as compared to natural ovarian cycles.

The purpose of the present study was to investigate the stability of vascular endothelial growth factor (VEGF) in plasma samples and the influence of ovarian hyperstimulation on systemic levels of VEGF. Stability assays for VEGF in plasma samples revealed significant increases following even short incubations of samples at room temperature (< or = 2 h, p < 0.001). To investigate a possible impact of controlled ovarian hyperstimulation (COH) on peripheral VEGF levels, serial blood collection over one menstrual cycle was performed in unstimulated as well as in gonadotropin-stimulated cycles for in vitro fertilisation/embryo transfer (IVF/ET) (10 women each). Peripheral levels for VEGF were significantly higher in gonadotropin stimulated cycles as compared to non-stimulated cycles (p < 0.001). There was no significant difference between follicular phase and luteal phase levels in either group. VEGF levels tended to correlate with the number of follicles detected by vaginal sonography prior to oocyte aspiration (p = 0.051). In conclusion, VEGF levels are elevated in gonadotropin-stimulated IVF/ET cycles as compared to natural cycles.

Chorionic Gonadotropin↗
PubMed2000

Role of Nd/Ba disorder on the penetration depth of Nd(1+x)Ba(2-x)Cu(3)O(7-delta) thin films

We report on a study on the effect of Nd/Ba disorder on the ab-plane penetration depth of epitaxial Nd(1+x)Ba(2-x)Cu(3)O(7-delta) thin films. While in stoichiometric samples lambda(T) at low temperature is linear, Nd-rich films exhibit a quadratic law. For low Nd excess (x<0.04), a satisfying fit is obtained using the "dirty" d-wave model assuming that Nd ions at Ba sites act as strong scattering centers. At high x (x>0.15) the data are explained if Nd/Ba disorder becomes less effective as a source of scattering. The effect of localization has been discussed to account for the experimental results.

Journal Article↗
PubMed2000

Findings of mycobacteria in insectivores and small rodents.

The organs of 30 insectivorous mammals and 62 rodents from areas inhabited by people or livestock where cattle paratuberculosis or mycobacterial infections of swine had been found to occur were examined by cultivation during the monitoring of occurrence and spread of mycobacterioses in cattle and swine. Mycobacteria were found in the organs of 3 insectivores (10%) and 6 rodents (9.7%). Mycobacterium chelonae was isolated from the organs of the lesser white-toothed shrew (Crocidura suaveolens) and the common vole (Microtus arvalis), and M. vaccae and M. avium subsp. avium (IS901+, serotype 1) from the organs of the common shrew (Sorex araneus). M. avium subsp. avium (IS901+, serotype 1) was also isolated from the organs of the yellow-necked mouse (Apodemus flavicollis). Slow-growing mycobacteria of group III (according to Runyon) were isolated from the organs of the mouse (Mus musculus sensu lato) and the yellow-necked mouse (A. flavicollis). These findings had no connection with the epizootological situation in the nearby livestock. M. fortuitum was isolated from the organs of the common vole (M. arvalis) caught in a field within easy reach of a swine breeding herd. M. fortuitum was also identified in the lymph nodes and droppings of this swine herd, as well as in the straw, scrapings from the floor of stalls, troughs and banisters, as well as from larvae and imagoes of dipterous insects. These results demonstrate the possibility that insectivores and small rodents can spread the causative agents of mycobacteria in wild and domestic animals.

Animal Husbandry↗
PubMed1993

Clavicular fracture of the neonate: can it be predicted before birth?

A retrospective study of 3873 cephalic vaginal births was undertaken to evaluate which factors are associated with clavicular fractures and thereby assess their clinical relevance in antepartum prediction. Fifty-two neonates with a fractured clavicle were identified, an incidence of 1.3%. Neonates with fractures were compared to a control group without fractures. The two groups were matched for age, parity, and mode of delivery. The neonates with fractures were found to be significantly heavier than controls, with mean birthweights of 3.7 kg and 3.2 kg, respectively (p = 0.000). Significantly more newborns in the fracture group weighed more than 4 kg (p = 0.02). A similar trend was noted when birthweights of previous pregnancies were compared (p = 0.03). Fracture cases had a greater incidence of low 1-minute Apgar scores (p = 0.02), and a higher proportion of births following abnormal progress of labor (19% of fracture group and 2.9% of controls; p = 0.001). Despite these statistically significant differences between the groups, it is not possible to predict most cases of fracture before birth, since the majority of fractures occur in cases not identified by any of the studied parameters.

Birth Weight↗