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Biomedical subjects

H Schmid

Publications and source records attributed to H Schmid.

At least 181 records · Page 10Linked to original sources
PubMed1985

Transdetermination in the homeotic eye--antenna imaginal disc of Drosophila melanogaster.

The effects of homeotic mutations on transdetermination in eye-antenna imaginal discs of Drosophila melanogaster were studied. After 12 days of culture in vivo, antenna discs transformed to ventral mesothorax by AntpNs or AntpZ, transdetermined to notum and wing structures four to five times more frequently than the corresponding wild-type antenna discs. Likewise, eye discs transformed to dorsal mesothorax by eyopt transdetermined to leg structures, also extremely frequently (90%). It seems that, during culture, homeotic antenna as well as homeotic eye discs tend to complete the structural inventory of the mesothoracic segment. Transdetermination in the homeotic disc parts is interpreted as a regeneration process which reestablishes an entire segment, i.e., the ventral mesothoracic portion (leg) in the antenna disc regenerates dorsal mesothoracic parts, and the dorsal mesothoracic portion in the eye disc (wing) regenerates ventral mesothoracic parts, respectively. This implies that antenna and leg discs (ventral qualities) as well as eye and wing discs (dorsal qualities) are serially homologous. The transdetermination frequency of the untransformed eye disc to notum and wing structures is enhanced by Antp to the same extent as is the transdetermination frequency of the antenna disc. The first allotypic wing disc structure formed by the eye disc is notum, followed by structures of the anterior wing compartment and finally by posterior wing structures. No evidence for such a sequence was found in the transdetermination pattern of the antenna disc.

Animals↗
PubMed1985

[Diagnosis of benign and malignant ovarian tumors].

The present paper reports on the value of gynecological-clinical examinations and preoperative ultrasonography in the diagnosis of benign and malignant ovarian tumors. Out of a group of 42 patients, in all of whom "ovarian cyst" had only been diagnosed clinically, 14% were not found to be suffering from this condition at surgery. In a comparison of preoperative gynecological-clinical and ultrasonographic findings (in 68 patients) it proved possible to determine the side on which the tumor was localized, its actual size, the extent to which it was delimited from the uterus, and its consistency (whether solid or cystic) significantly better by ultrasonography (p less than 0,01). However, the results of this study indicate that 2% of the cases diagnosed ultrasonographically as "benign ovarian tumor/ovarian cyst" are likely to be ovarian carcinomas. In the group of patients with malignant ovarian tumors also (42 patients), there was a significant difference in the preoperative diagnosis "suspected ovarian carcinoma". On the basis of clinical findings it was only diagnosed in 45%, while it was found in 74% by ultrasonography (p less than 0,01). In 3 cases with ovarian carcinoma there was no pathologic palpation finding, and in only one other case was a "suspected ovarian cyst" diagnosed. By means of ultrasonography, on the other hand, all of the cases of ovarian carcinoma were classified either as "ovarian carcinoma" or as "cystic-solid/complex abdominal tumor". The most frequent diagnoses on the basis of the sonographic scan (approx. 90%) were cystic-solid ovarian tumors, followed by cystic-ventriculated ovarian tumors with solid portions and finally solid ovarian tumors with only a few cystic portions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

Altered distribution pattern of Na+-K+-ATPase and succinate dehydrogenase activities along the nephron in human acute post-transplant renal failure.

The catalytic activities of Na+-K+-ATPase and succinate dehydrogenase, marker enzymes for active salt reabsorptive capacity of renal basolateral plasma membranes and for respiratory capacity of mitochondrial cristae membranes, were studied in the maintenance phase of human acute post-transplant renal failure. Biopsies of 4 kidney-allografts taken at transplantation operation and additionally at different post-transplantation periods, either with good function or in various stages of dysfunction, were compared with the unaffected part of a human kidney nephrectomized due to hypernephroma. In single nephron segments, Na+-K+-ATPase activity was determined after microdissection by microfluorometry, and succinate dehydrogenase activity was determined by a microphotometric procedure in stained cryosections. In intraoperative and postoperative biopsies of a well-functioning allograft, both Na+-K+-ATPase and succinate dehydrogenase activities did not differ from those of normal renal tissue. In contrast, the catalytic activities were found to be decreased in the distal tubules of 2 anuric allografts when compared with their intraoperative controls. In addition, succinate dehydrogenase activity was reduced in distal tubules of a recovering allograft. Catalytic activities appeared to be unaffected in glomeruli, proximal tubules, and collecting ducts. It is suggested that the predominant distal tubular alterations with regard to these parameters are a consequence of increased distal tubular vulnerability due to circulatory and metabolic conditions.

Acute Kidney Injury↗
PubMed1984

[Sodium chloride intake and supply of iodine in the Swiss population].

The controversial salt intake in a representative sample of the Swiss adult population was evaluated by measuring the sodium excretion in the urine of 966 adult probands of different regions in Switzerland. Prior to this study the validity of a widely used and easy method for the analysis of sodium excretion in large scale studies was investigated by determination of the quotient of sodium excretion and creatininuria in a single urine sample and the calculation of the 24-h values. The results with this method were compared to those of determination of effective sodium content in the 24-h urine samples of 43 probands. Similar mean values were demonstrated for both methods. On the other hand, only 53.5% of the individual results were between +/- 30% of the effective values. It is therefore concluded that this method is useful only for large scale studies but not for individual evaluations of sodium excretion. The mean sodium excretion was 176.2 +/- 105.9 mmol/24 h for the 966 probands. This corresponds to a daily salt intake of 10.3 +/- 6.2 g. Determination of the effective sodium excretion in 24-h urine samples of 147 probands, which differed slightly from the whole collective with regard to age and sex distribution, confirmed these data with a mean sodium excretion of 143.2 +/- 62 mmol/24 h, corresponding to a daily salt intake of 8.4 +/- 3,6 g. Iodine excretion in the 24-h urine samples of 112 probands completed the study.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1984

[Treatment of intestinal atony following gynecologic operations. Study on the effectiveness and tolerance of ceruletide].

The efficacy and tolerability of Ceruletide and Neostigmin were compared in patients with postoperative intestinal atonia after extensive gynecological surgical operations. Patients treated with Ceruletide (n = 30, dosage of Ceruletide 2 ng/kg/min. i.v.) showed earlier defecation than the Neostigmin-group (n = 30, dosage of neostigmin 3 x 0,5 mg/die). The frequency of side effects was comparable in both groups, patients treated with Ceruletide suffered mainly from gastrointestinal symptoms (nausea) whereas patients treated with Neostigmin complained of disorders of circulation. Ceruletide is faster effective than Neostigmin, the tolerability of both drugs is equivalent.

Blood Pressure↗
PubMed1984

Reduced lipogenesis in rats fed a high-protein carbohydrate-free diet.

Rates of fatty acid synthesis were assessed in carcass, liver, and adipose tissue from rats fed for 30 to 40 days a balanced diet (66% wt/wt carbohydrate, 17% casein, 8% fat) or a high-protein carbohydrate-free diet (70% casein, 8% fat). Despite similar body weight increases, carcass fatty acid content of rats on the high-protein (HP) diet was 13% less, and the weight of their epididymal fat pads was reduced by 29% in relation to the controls. In vivo incorporation of 3H2O into carcass fatty acids (FA) and into liver triacylglycerol (TAG) was significantly reduced in HP-fed rats. FA synthesis from 14C-acetate, glucose, or leucine and from 3H2O was also markedly decreased in liver slices from HP rats. The amount of 3H-TAG that accumulated in plasma of rats injected with triton WR 1339 to block peripheral utilization of lipoprotein corresponded in HP and control rats to only 4.1% and 5.0%, respectively, of 3H-FA recovered in carcasses from animals not treated with triton, indicating that almost all of the carcass 3H-TAG was synthesized in situ. However, on a long term basis, the reduced hepatic lipogenesis and the resulting decreased transport of TAG might affect lipid accumulation in HP rats. In vivo lipogenesis from 3H2O and in vitro FA synthesis from 3H2O and from 14C-precursors did not differ significantly in retroperitoneal and epididymal adipose tissue from HP and control rats. In both groups of animals, in vivo rates of lipogenesis were higher in retroperitoneal than in epididymal adipose tissue but still did not account for rates of FA synthesis by carcasses, suggesting the existence of other sites with higher lipogenic activity.

Adipose Tissue↗
PubMed1984

[Clinical management of bronchopulmonary dysplasia].

Bronchopulmonary dysplasia is caused by several factors. Avoidance of bronchopulmonary dysplasia is directed at its causes and should always attempt the rapid weaning of the patient from the respirator. Some of the preventive measures include a) avoiding an oxygen injury; b) prevention of barotrauma; 3) sufficient moisturization and warming of the respiratory gases; d) regular cleaning of the respiratory tract and bacterial controls of the tracheal secretion; e) administration of vitamin E; f) reconsideration (restricting the use) of parenteral nutrition. Assistance in the weaning from the respiratory means a) avoidance of an open ductus arteriosus; b) paced reduction of FiO2, respiratory pressure and frequency up to intermittent mandatory ventilation and final transition to spontaneous respiration with increased mean respiratory pressure; c) avoidance of cardiac insufficiency; d) administration of corticosteroids; e) theophyllin, and f) physical therapy. The number of patients with bronchopulmonary dysplasia has remained the same in the last six years. However, the mortality until 1979 round about 50% has been reduced to 1/3, in the years 1980/81.

Bronchopulmonary Dysplasia↗
PubMed1984

Quantitative microphotometric succinate dehydrogenase histochemistry in human nephron.

A simple method for microphotometric evaluation of cryostat sections from human renal tissue routinely stained for succinate dehydrogenase activity by means of tetranitro-blue tetrazolium chloride is described and tested for validity. Manual absorbance measurement within single nephron segments from the same section allows to directly visualize the distribution pattern of this enzyme along the nephron. Photometric data can be expressed in relative enzyme activities by using the cortical collecting ducts within the same section as reference. This allows to compare measurements of different kidney sections stained by various incubation procedures. The agreement found between relative succinate dehydrogenase activities and recently published morphometric data on mitochondrial inner membranes along the rat nephron suggests that quantitative succinate dehydrogenase microphotometry is a useful histochemical tool for the assessment of renal mitochondrial cristae membranes.

Histocytochemistry↗
PubMed1983

Tracing of sensory neurones and spinal motoneurones of the pigeon by injection of fluorescent dyes into peripheral nerves.

The projection of peripheral sensory and motor nerves was investigated in the pigeon (Columba livia) by means of retrogradely transported fluorescent dyes. Two combinations of fluorescent tracers were used that could be identified within the same cell when excited by light of 405 nm: 1) Propidium iodide and Bisbenzimide, which label the cytoplasm orange and the nucleus blue, respectively; 2) Fast Blue, which labels the cytoplasm blue, and Nuclear Yellow, which labels the nucleus (especially the nucleolar ring) yellow. The presence of the tracers in a given cell was confirmed microspectrophotometrically. Following injection of the tracers into peripheral nerves, labelled sensory neurones were seen in the dorsal root ganglia and motoneurones of the spinal cord. The peroneal and tibial nerves projected to L2-L5 and L2-L7, respectively, whereas the median and ulnar nerves projected to C12-Th2 and C13-Th1. Double-labelled sensory neurones were observed when both peroneal and tibial, or median and ulnar nerves were injected with different tracers. This indicates that some sensory neurones possess peripheral processes that dichotomize to pass down two different peripheral nerves. Double labelling was never seen in motoneurones, or in sensory neurones after tracer injection into the sciatic and femoral nerves.

Animals↗
PubMed1983

The use of fluorescent tracers in the peripheral sensory nervous system.

We have developed an injection technique which simplifies the use of fluorescent tracers in investigating the projections of peripheral nerves both in rats and pigeons, and avoids the difficulties experienced with the cut nerve technique. The tracers are injected into the peripheral nerve and transported to cell bodies in the dorsal root ganglia (DRG). By a careful choice of tracer it is possible to investigate the projections of two or more nerves in the same preparation. We have used two combinations of tracer which can be viewed simultaneously in the cell at the same excitation wavelength (405 nm): (1) propidium iodide (PI) and bisbenzimide (Bb) which produce an orange cytoplasmic fluorescence and blue nuclear fluorescence respectively; and (2) Fast blue (FB) and Nuclear yellow (NY) which label the cytoplasm blue and the nucleus yellow. This distribution of tracers is similar to that reported in central neurones but differs from that reported in the efferent peripheral nervous system. Using these tracers we have observed double-labelled neurones in the DRG of both rats and pigeons, which is an indication for the dichotomizing of peripheral fibres. The existence of two tracers in double-labelled cells has been confirmed microspectrophotometrically.

Animals↗