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T Berger

Publications and source records attributed to T Berger.

195 records · Page 11Linked to original sources
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Fluorescent probes and flow cytometry to assess rat sperm integrity and mitochondrial function.

Fluorescent assessment of cellular integrity and mitochondrial function by flow cytometry can provide a rapid and precise means of determining the functional status of large numbers of spermatozoa. In the present study, rat sperm viability was assessed with SYBR-14 and PI and sperm mitochondria were differentially labeled with JC-1. Sperm samples of variable viability were prepared using varying proportions of fresh and frozen spermatozoa. SYBR-14 stained sperm correlated well with expected sperm viability (r = 0.98). Motile sperm stained with JC-1 appeared orange in the midpiece indicating a high mitochondrial membrane potential whereas immotile sperm with a low membrane potential stained green. The percentage of spermatozoa staining orange was highly correlated (r = 0.99) with expected sperm viability. Flow cytometry using specific fluorescent probes is a useful technique for detecting changes in rat sperm plasma membrane integrity and mitochondrial function in large numbers of spermatozoa.

Animals↗
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alpha-chlorohydrin induced changes in sperm fertilizing ability in the rat: association with diminished sperm ATP levels and motility.

In the present study, alpha-chlorohydrin (ACH) (5, 10, 25, 50 and 75 mg/kg, po) was administered to rats and the effects on sperm ATP levels, sperm motility, and the ability of sperm to bind and penetrate rat oocytes were determined. Groups of rats were killed 5 days and 3 h following treatment. At both time points, sperm from ACH-treated rats (>/=10 mg/kg) had significantly lower levels of ATP when diluted in media containing glucose. No diminution of ATP was seen in sperm diluted in phosphate-buffered saline (PBS). Computer analysis of sperm motility indicated that straight-line velocity (VSL) was the most sensitive parameter to ACH treatment and was significantly decreased in rat sperm three hours after ACH exposure (25 mg/kg). A clear drop in percent penetration (35% vs. 85% in control) of zona-free rat oocytes by rat sperm of both ACH groups was observed at 10 mg/kg. Higher dose levels produced no significant further decrease in percent penetration. Overall, the fertilizing ability of sperm was highly sensitive to ACH doses that caused minor but significant changes in sperm ATP levels and no significant changes in motility. These data are consistent with the spermatozoan's need for an uncompromised energy supply to maintain its ability to bind and penetrate the oocyte.

Adenosine Triphosphate↗
PubMedDate not supplied

In vitro fertilization after in vivo treatment of rats with three reproductive toxicants.

One objective of these experiments was to establish a sensitive assay to evaluate fertilizing potential of rat gametes in vitro. A second objective was to evaluate this in vitro fertilization (IVF) assay as a method to detect in vivo effects of reproductive toxicants on male and female gametes using three known reproductive toxicants as model systems. The IVF assay with zona-free oocytes was more precise than the assay with cumulus-intact oocytes in these studies (coefficients of variation of 8.7 and 14.4%, respectively). Sperm fertilizing potential for zona-free oocytes was reduced by treatment of rats with m-dinitrobenzene (10-10 000 microg/kg) and ethylene glycol monomethyl ether (50-100 mg/kg) that had no effect on sperm motility. Molinate (60 mg/kg for 5 days) reduced sperm fertilizing potential concurrently with reductions in sperm motility. Neither molinate (60 mg/kg for 5 days) nor dinitrobenzene (0.002% in the drinking water for 14 days) administered to females seemed to affect the fertilizability of their oocytes. Ethylene glycol monomethyl ether treatment (0.15-0.25% in the drinking water for 14 days) reduced the number of ovulated oocytes. IVF is a means to evaluate toxicant effects on female gametes and demonstrates sperm's ability to interact with the oocyte plasma membrane.

Animals↗
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[Steroids for prophylaxis of nephropathy in Schnlein Henoch purpura? Follow-up of 171 patients].

UNLABELLED: The necessity of the controversially discussed general steroid prophylaxis in Henoch-Schönlein Purpura (HSP) was analysed based on frequency, risk factors and prognosis of renal involvement. Case histories and follow up of at least 1.5 years were evaluated in all 171 patients (median age 6 years) in our institution suffering from HSP between 1.1.1987 and 30.6.1997. HSP was frequently manifest with an involvement of joints (64%) and gastrointestinal tract (58%). Renal involvement occurred in only 29% of the children. Excepted one girl (age 12 year), all children with renal disease completely recovered. Renal involvement was significantly rarer in young children (16%) and after one week therapy with prednisone (7%). In young children, renal involvement always followed abdominal pain. CONCLUSION: In our collective, a general preventing of renal disease in HSP was unnecessary. Especially in young children, the most common manifestation age, renal involvement rarely occurred and had always a good prognosis.

Abdominal Pain↗
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[Acute otitis media in children: an evidence-based practice guideline].

Acute Otitis media is one of the most common acute respiratory infections managed in primary care and the most common infection among in children. Diagnostic criteria, however, do not always correspond to scientific evidence. They often differ depending on individual preferences and competences. Treatment, also, is controversial. In Germany, most children attending their pediatrician or primary care physician will be prescribed antibiotics. Evidence from several randomized studies and systematic reviews suggests that routine usage of antibiotics provides only modest benefit. The benefit of prescribing antibiotics should not only be balanced against the increased likelihood of side effects such as diarrhoea but also against the potential to contribute to longterm antibiotic resistance.

Acute Disease↗
PubMedDate not supplied

The angry voice: its effects on the experience of anger and cardiovascular reactivity.

The results of two studies show that expressive vocal behavior, specifically, speech rate and loudness, influences the experience of anger and cardiovascular reactivity. In both studies, participants spoke about anger-arousing and neutral events using three different voice styles: fast and loud, slow and soft, and normal (personal rate and loudness level). In describing the anger-arousing events, both male and female participants reported feeling significantly more angry and showed significantly greater blood pressure and heart rate reactivity in the fast-loud compared with the normal speaking condition. They also reported feeling significantly less angry and showed significantly lower blood pressure reactivity in the slow-soft compared with the normal voice condition. For males only, the voice manipulation also had significant effects on the participants' anger self-ratings and cardiovascular responses during the neutral communications, but these effects were clearly weaker and less pervasive than those occurring during the angry communications. The results are discussed in terms of their implications for (1) the role of expressive vocal behavior in emotions, and (2) the modification of coronary-prone behavior.

Adult↗
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Effects of inhibitors of the catecholamine synthesis on motor activity in the rat during light and darkness.

Under controlled conditions of light and darkness (12:12 hrs) the influence of inhibitors of the tyrosine-hydroxylase (alpha-MT) and dopamine-beta-hydroxylase (FLA 63) on motor activity were investigated in male Wistar rats at different times of the day. Simultaneously, turnover experiments of the cerebral noradrenaline and dopamine were performed, which revealed diurnal variations within 24 hrs of a day. Both inhibitors showed clear-cut chronopharmacological differences in influencing motor activity, and a phase shift between the darkness-induced increase in motor activity and the maximum turnover rate of the cerebral dopamine was observed.

Animals↗
PubMedDate not supplied

Altering glomerular epithelial function in vitro using transient and stable transfection.

Damage of the glomerular filtration barrier leads to proteinuria and progressive renal failure. Several independent lines of research have implicated the glomerular epithelial cell (GEC) as a key player in initiation and propagation of pathways leading to glomerulosclerosis. A growing number of molecules activated in this process have been identified. To further define their cellular function, manipulation of these molecules using pharmacological or genetic approaches in tissue culture systems are required. In this study, strategies for altering GEC gene expression by transient and stable transfection of fluorescence labeled proteins will be presented and discussed. The insight gained through these and comparable systems should allow a detailed dissection of the molecular pathways active in GEC function and failure.

Cells, Cultured↗
PubMedDate not supplied

[Gadolinium DTPA in magnetic resonance. Clinical experience in intracranial pathology].

Sixty-seven patients with various intracranial pathologies were studied using Gd-DTPA as a contrast medium applied to MRI. This paramagnetic substance was well tolerated by all patients, and proved particularly useful in improving the diagnosis of extra-axial tumors, in which a rich enhancement was always present. Gd-DTPA allowed a better definition of the tumor outlines, as well as its differentiation from edema, and the demonstration of its relationship to brain parenchyma and cerebral vessels. This was particularly true for meningiomas, which often display poor contrast enhancement at MRI. Even though acoustic neuromas had, as a rule, high signal intensity, Gd-DTPA was useful to precisely recognize the intracanalar part of the tumor. The value of Gd-DTPA was less evident in intra-axial lesions. It proved nonetheless useful in demonstrating the portions of the tumor where, due to alterations in BBB, enhancement was present. This allowed both to characterize the lesion and to perform accurate biopsies.

Brain Neoplasms↗