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Biomedical subjects

V Schulz

Publications and source records attributed to V Schulz.

At least 73 records · Page 4Linked to original sources

[Studies on the influence of releasing hormones TRH and CRH on respiratory regulation].

Patterns of neuroanatomical distribution of Thyrotropin-releasing hormone (TRH) and Corticotropin-releasing hormone (CRH) and of their receptors in brain areas of humans and of animals suppose a regulating function of both peptides on regulation of respiration. In experimental animals TRH induces rhythmical and synchronous firing of defined neurons of nucleus tractus solitarii. In fetal sheep, endogenous and exogenous CRH promotes maturation of breathing rhythm genesis. In own human studies we demonstrated a modulation of respiration in healthy test-subjects - predominantly a stimulation of respiration - by systemic TRH and CRH. This effect persists also during hypercapnia, as we showed in patients and in 12 healthy test subjects while re-breathing CO2: when compared to placebo, CRH i.v. (200 micrograms. Bissendorf, Hannover, FRG) induces a significant (p less than 0.0001) shift of the ventilatory response curve to the left (petCO2 vs minute volume). Stimulation of respiration by CRH is independent of activation of the pituitary-adrenal axis. At present two analogues of CRH are available for application in humans (as a diagnostic of endocrinological disorders): human CRH and ovine CRH. Both analogues are comparably effective in stimulation of ventilation although sequence of effects is different in both analogues. We also evaluated the effect of CRH in 10 aged patients who were under prolonged respirator therapy after major abdominal surgery; both human and ovine CRH (100-200 micrograms i.v.) induced a profound and long lasting stimulation of ventilation under assisted respirator therapy. Vigilance was also markedly increased in all patients and thus was of therapeutic value. CRH also has a potential to alter sleep architecture in healthy and in diseased persons.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

High cell density fermentation of recombinant Escherichia coli expressing human interferon alpha 1.

A defined medium was developed which, by means of a specific fed-batch mode, allows growth of the recombinant Escherichia coli strain TG1 (pBB210) up to a cell density of 60 g dry weight/l. Apart from glucose and aqueous ammonia fed as carbon and nitrogen sources, it was necessary to supply other nutrients or O2-enriched air. Aqueous ammonia also served for pH control. The pO2 level was kept at 20% saturation via closed-loop controls operating the two output variables of stirrer speed and glucose feeding rate. This fed-batch method prevented significant accumulation of acetate and other metabolic by-products. The recombinant E. coli expressed interferon alpha 1 more efficiently at a lower specific growth rate (muPr approximately 0.15 h-1) than at the maximum specific growth rate (mu max = 0.45 h-1). Therefore, fermentation in the batch phase at mu max was only allowed to continue up to a medium cell density. In the succeeding fed-batch phase, the specific growth rate was reduced to muPr by increasing the stirrer speed according to an empirically developed time scale.

Ammonia↗

[Clinical aspects, results of diagnostic pulmonary function tests and biochemical parameters in children with homozygote alpha-1-antitrypsin deficiency].

The clinical course and pulmonary function tests of individuals with severe Alpha-1-Antitrypsin (Alpha-1-AT) deficiency reveal a marked interindividual variability. 4 patients with PI type ZZ and 2 patients with PI type SZ had been identified by neonatal cholestasis. None had pulmonary symptoms at a mean age of 13 (range 9-16) years. Lung function tests disclosed signs of incipient pulmonary emphysema in one girl. Bronchial hyperreactivity had led to the diagnosis of Alpha-1 AT-deficiency (PI type ZZ) in another girl at the age of 7 years. The biochemical analysis of the serum of three children (two PI ZZ and one PI SZ) revealed additional protease inhibitors that may be effective as compensatory mechanisms. The lack of those protective factors as well as the presence of environmental hazards may contribute to the increased risk of emphysema in individual patients.

Adolescent↗

[Bronchiolitis obliterans following nitrogen dioxide (NO2) inhalation: clinical-roentgenologic-histologic study].

A case of bronchiolitis obliterans after prior inhalation of NO2 is described. The diagnosis was confirmed histologically following diagnostic thoracotomy and biopsy by means of pulmonary wedge resection. The clinical course of the case was compatible with the typical phases described in the literature, and the condition underwent complete remission following treatment with corticoids.

Air Pollutants, Occupational↗

[Trypsin and pancreatic elastase-inhibitory capacity of serum and bronchoalveolar lavage fluid of smokers, ex-smokers and nonsmokers].

Smoking habits have no differentiating effect on the functional activity of protease inhibitor (alpha 1PI) in the serum and bronchoalveolar lavage fluid (BALF). In the BALF, the trypsin-inhibitory capacity TIC/alpha 1PI ratio is significantly greater in patients with emphysema than in non-emphysematous subjects. PIC/alpha 1PI ratios that are greater than 1 demonstrate the existence of additional antiproteases in the lower respiratory tract.

Bronchoalveolar Lavage Fluid↗

[Fading of the provocation effect following inhaled provocation with carbachol].

The results of the present study aimed at establishing the subsidence of the effect of inhalative provocation with carbachol show that no ceiling activity is reached. Rather, following a maximum effect that is achieved after approximately 2 minutes, spontaneous subsidence of the provocation-related changes occurs. The average duration of this subsidence to below the level of change that is considered significant for the respective measured parameter was between 20 and 25 minutes.

Adult↗

[Clinical aspects, diagnostic lung function and biochemical parameters in children with homozygous alpha 1-antitrypsin deficiency].

Both the clinical course of the homozygous alpha 1-PI deficiency and also the pulmonary function and measured clinical parameters in these children revealed very marked inter-individual fluctuations. In one child, the lung function revealed certain signs of incipient pulmonary emphysema. The biochemical parameters of two children revealed TIC/alpha 1-PI- and PEIC/alpha 1-PI ratios greater than 1. This indicates that, in addition to alpha 1-PI, further inhibitors may develop a compensatory effect.

Child↗

Pseudorevertants of a lac promoter mutation reveal overlapping nascent promoters.

Four pseudorevertants of a -10 region lacP mutation were isolated. Three of these mutations were found to activate nascent promoters. These mutations were: a -2 G/C----A/T change (-2A) promoting transcription at position +11, a +1 A/T----T/A change (+1T) promoting transcription initiation at position +13, and a +10 C/G----A/T change (+10A) promoting transcription initiation at a complex series of positions. The fourth mutation [a -12 T/A----A/T change (-12A)] promotes transcription initiation at -1. The promoters activated by mutations -12A, -2A and +1T resembled the canonical sigma 70 promoter sequences. The +10A promoter activity is also dependent upon the sigma 70 holoenzyme but can not be readily assigned to a specific promoter sequence.

Escherichia coli↗

Study of possible teratogenic effects of the fungicide maneb on chick embryos.

The teratogenicity of the fungicide maneb (80% active ingredient and 20% inert ingredients) in chick embryos was evaluated. Eggs, before incubation, were dipped in 0.2% or 1.2% aqueous dispersions of maneb for 30 seconds. An untreated group, a water group and a formulation ingredient group, at the concentration present in the 1.2% maneb group, ensured control in the study. Eggs were incubated for 18 days then transferred to hatching racks and allowed to hatch normally. Viable chicks and chicks "dead in shell" were assessed for external deformities. There was no evidence that maneb or its formulation ingredients were teratogenic or embryotoxic to developing chick embryos.

Animals↗

[Treatment of hemoptysis by embolization of the thoracic arteries with Ethibloc].

Between November 1983 and July 1988 28 patients with haemoptysis were treated by transcatheter embolisation. Clinical follow-up of 22 patients revealed that 5 patients rebled within 21 days after embolization. Haemoptysis ceased completely in the remaining 17 patients. However, 2 patients rebled after 4 and 12 months, respectively. We observed two transient spinal cord injuries, most likely related to spinal cord ischaemia. In the first patient an intercostal artery was embolised with Ethibloc, in the second patient with Gelfoam. In summary, we can say that due to the inherent risk of spinal cord injury, embolisation should be restricted to patients in whom other forms of treatment failed or proved impossible. Ethibloc may be alternatively used for embolisation.

Adult↗

[Lung perfusion-ventilation scintigraphy in squamous cell carcinoma of the lung].

The effect of tumour size, as determined surgically, and tumour position, as determined by bronchoscopy, on ventilation and perfusion scintigraphy was examined in 53 patients with squamous cell carcinomas of the lung. The findings were compared with reduction in one-second-capacity. Central tumours were frequently associated with marked reduction in perfusion. In these patients there was a linear positive correlation between ventilation and one-second-capacity. The reduction in perfusion, and the need to measure this, became with more peripheral tumours. There was a correlation between ventilation and tumour size in patients with V/Q quotient of greater than 1.2. The results show that tumour size and position do not necessarily indicate operability. For planning surgery of central tumours, perfusion scintigraphy therefore occupies an important position.

Aged↗

[Functional activity of the alpha1-proteinase inhibitor in serum and bronchoalveolar lavage fluid in congenital lung emphysema].

Pulmonary emphysema is thought to be due to an elastase-antielastase imbalance which leads to the destruction of alveolar walls. It is generally agreed that cigarette smoking is the major cause of acquired emphysema although many smokers fail to develop overt disease. Cigarette smoke inactivates alpha 1-proteinase inhibitor (alpha 1PI) which is believed to be the major antielastase in the lower respiratory tract. There is, however, controversy regarding the activity of alpha 1PI in smokers compared with nonsmokers. We, therefore, investigated the trypsin inhibitory capacity (TIC), the pancreatic elastase inhibitory capacity (PEIC), and the amount of immunoreactive alpha 1PI in serum and bronchoalveolar lavage fluid (BALF) of 24 individuals (15 smokers, 5 former smokers, 4 non-smokers) with clinical signs of emphysema and 32 persons (15 smokers, 6 former smokers, 11 non-smokers) without emphysema. Pancreatic elastase is known to be inhibited only by non-oxidised alpha 1PI whereas trypsin is inhibited by both native and oxidised alpha 1PI. Serum values of TIC/alpha 1PI and PEIC/alpha 1PI did not differ between the groups of subjects with emphysema (TIC/alpha 1PI: 0.71 +/- 0.12; PEIC/alpha 1PI: 0.44 +/- 0.06) and without emphysema (TIC/alpha 1PI: 0.68 +/- 0.13; PEIC/alpha 1PI: 0.41 +/- 0.07). Both serum-inhibitory capacities were found to be smaller than unit (= 1) indicating inactivation of alpha 1PI. BALF values of TIC/alpha 1PI showed a wide variation. TIC/alpha 1PI was greater than unity in 84% of subjects with emphysema (2.06 +/- 1.28) compared to 61% without emphysema (1.14 +/- 1.07) providing evidence for the presence of additional inhibitor(s) in those lavage fluids.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Proteins↗

[Thoracoscopic diagnosis and therapy of spontaneous pneumothorax].

Thoracoscopy must be regarded as an obligatory procedure in the diagnosis and therapy of symptomatic spontaneous pneumothorax. In up to 81% of cases data obtained by thoracoscopy considerably influence therapy. Indication for surgery has to be weighed against endoscopic therapy (coagulation, laser and pleurodesis). Thoracoscopy should be performed at the first recurrence of an idiopathic spontaneous pneumothorax, unless the lung does not expand during suction drainage or recollapses after expansion.

Aprotinin↗

A macrophage-suppressing 40-kD protein in a case of pulmonary alveolar proteinosis.

Pulmonary alveolar proteinosis (PAP) is a rare disease of unknown etiology. Macrophage dysfunctions are claimed to be involved in the pathogenesis. We investigated phagocytosis and oxidative metabolism of alveolar macrophages in a case of pulmonary alveolar proteinosis. These cells phagocytize normally and phagocytizable stimulants cause a normal oxidative burst. In response to the membrane signals phorbolmyristate acetate and aggregated immunoglobulin, however, no stimulated turnover of the oxidative metabolism can be observed. A 40-kD protein found in the lavage fluid mediates this macrophage-inhibiting effect. This phenomenon may contribute to the frequent opportunistic infections seen in PAP patients. It can be concluded from our data that the high frequency of infections with opportunistic species in these patients can be reduced by therapeutic bronchoalveolar lavage. By this procedure the abnormal macrophage-suppressing protein can be washed out of the lung at an early stage of the disease.

Adult↗