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Biomedical subjects

H Lutz

Publications and source records attributed to H Lutz.

At least 181 records · Page 10Linked to original sources
PubMed1986

Post-exposure treatment with monoclonal antibodies in a retrovirus system: failure to protect cats against feline leukemia virus infection with virus neutralizing monoclonal antibodies.

We have attempted to protect kittens against oronasal infection with FeLV (strain A/Glasgow-1) by treatment with a mixture of two virus-neutralizing (VN) MAbs (IgGl, K) directed against the same epitope on the viral glycoprotein gp70. Ten SPF 9-week-old kittens were infected on day 0 with 10(6) ffu FeLV and subsequently inoculated i.m. with MAbs every 2 days over a 20-day period at different times after infection. The results clearly show that no protection was achieved. It is unlikely that the amount of VN antibodies, the mode and route of their application or the infectious dose of FeLV used can account for the failure to protect cats against infection. Other possibilities which may explain the lack of protective effect are that the restricted epitope specificity of the MAb preparation used may have led to selection of neutralization-resistant virus mutants, or that other mechanisms than virus neutralization (complement-mediated lysis, antibody-dependent cell cytotoxicity), that may be involved in protection, function less efficiently with MAb. However, in the light of our finding that an early anti-idiotypic response is observed in all cats following administration of the MAb preparation, the rapid clearance of anti-FeLV MAb from the circulation is a more likely explanation. The data presented support our hypothesis that by administration of MAb-as compared to polyclonal antibody-a more vigorous anti-idiotypic response is elicited due to the presentation of only a limited set of idiotopes. This potential drawback of rapid clearance of MAbs as a consequence of an anti-idiotypic response might be overcome by the use of mixtures of MAbs resulting in a more heterogeneous set of idiotypic determinants.

Animals↗
PubMed1986

[Ultrasonic endoscopy. An assessment after 3 years].

A high-resolution ultrasound head at the tip of an endoscope, used in 259 examinations of 232 patients, has been demonstrated in general to fulfill the expectations placed on it as an important diagnostic tool.

Adolescent↗
PubMed1986

Side effects of positive pressure ventilation on hepatic function and splanchnic circulation.

Positive pressure ventilation is associated with a reduction and redistribution of cardiac output. Splanchnic blood flow is decreased. Blood supply of the liver is reduced exceeding the fall in cardiac output. As a result oxygen transport to the mesenteric bed and liver is curtailed. There is a concomitant impairment of hepatic venous outflow. These hemodynamic changes may cause functional, structural and metabolic disturbances in organs whose blood supply arises from splanchnic circulation.

Bile Ducts↗
PubMed1986

[Ultrasound diagnosis of the stomach wall--experimental studies].

The gastrointestinal wall can be separated into 5 layers by means of ultrasonic endoscopy and also by external ultrasound when using a probe of 5 Mhz. We studied the relationship between these echographic layers and the real anatomical structures by means of in-vitro examination of surgical specimens. The anatomical layers were separated in these specimens step by step. We found that the first and the fifth hyperechoic layers are border echos. The 2. (inner echopoor layer), the 3. (middle echogenic layer) and the 4. (outer echopoor layer) correspond to the mucosa, the submucosa and the muscularis propria, respectively. In so far, the differentiation between early cancer and advanced cancer of the stomach should be possible by endoscopic ultrasonography.

Gastric Mucosa↗
PubMed1986

[Sonography of chronic inflammatory bowel diseases--a prospective study].

In a prospective study, 118 patients with Crohn's disease, 51 patients with ulcerative colitis, and 72 patients with no disease of the intestine proximal to the rectum, were investigated by ultrasound. In Crohn's disease, thickening of the bowel wall and inflammatory conglomerates were detected in 72.0% of the patients. Using a transducer with optimal imaging properties these findings were detected in 87.2% of a group of 47 patients. Additionally an abscess was found in 5 patients. In ulcerative colitis, bowel wall thickening was detected in 52.9% of all patients. In both conditions, the extent of the mural changes was recognized completely in individual cases only. In Crohn's disease, the wall thickening was, on the whole, more marked, and an accumulation of pathological findings was found in the right lower abdomen. In the case of ulcerative colitis, on the other hand, the wall thickening was less pronounced, and located particularly in the left lateral abdomen. In the comparative group, low-grade thickening of the wall was observed in 3 cases only. The ultrasonographic image permits no conclusions to be drawn as to the degree of activity of the disease, although, in ulcerative colitis, the number of positive findings increases with increasing activity. No correlation of the findings with the duration of the disease was established. Considerably increased wall thickness if localized in the right lower quadrant and found in combination with an inflammatory conglomerate or an abscess, suggests Crohn's disease. It is not possible to exclude either disease by means of ultrasound.

Abscess↗
PubMed1986

Effects of fluid-percussion brain injury on regional cerebral blood flow and pial arteriolar diameter.

The effects of two levels of fluid-percussion brain injury on cerebral blood flow (CBF) and pial arteriolar diameter were investigated in cats. Regional CBF was measured using the radioactive microsphere technique. Experimental brain injury resulted in changes in arterial blood pressure, CBF, and pial arteriolar diameter that were related to the severity of the injury. Low-level injury (1.88 +/- 0.11 atm, mean +/- standard error of the mean) resulted in a slight transient increase in CBF which had returned to preinjury levels by 30 minutes. High-level injury (2.68 +/- 0.19 atm) resulted in larger, statistically significant (p less than 0.01) increases in whole-brain CBF, decreases in cerebrovascular resistance, and increases in pial arteriolar diameter 1 minute postinjury. One hour after injury, CBF had returned to preinjury levels while cerebral perfusion pressure was significantly (p less than 0.01) reduced. There was no evidence of reduced CBF in any region studied. Pial arterioles dilated during the posttraumatic hypertensive period and then returned to control diameters within 1 hour after injury. Changes in the diameter of pial arterioles were significantly correlated with posttraumatic changes in CBF.

Animals↗
PubMed1986

Prognostic significance of ventricular CSF lactic acidosis in severe head injury.

Brain-tissue acidosis inferred by cerebrospinal fluid (CSF) lactic acidosis is considered to play an important role in the clinical course of severe head injury. Ventricular CSF lactate concentration was studied in 19 patients during the first 5 days after severe head injury. All patients were intubated, paralyzed, and artificially ventilated so that PaCO2 was kept at 33.2 +/- 5.0 mm Hg and PaO2 at 122 +/- 18 mm Hg (mean +/- standard deviation). The mean Glasgow Coma Scale score on admission was 5.73 +/- 2.42. The first CSF sample was drawn within 18 hours after head injury. Over the first 4 days postinjury, patients with a poor outcome had significantly higher ventricular CSF lactate levels than did those with moderate disabilities or a good outcome. Patients showing favorable outcome had a significant decrease in ventricular CSF lactate levels 48 hours after injury. This decrease was not observed in patients with a poor outcome. Increased ventricular CSF lactate concentration was also reliably associated with increased intracranial pressure (ICP). Ventricular CSF lactate levels did not correlate with the magnitude of intraventricular bleeding. Arterial and jugular venous blood lactate levels, although high after head injury, were usually lower than the levels in the ventricular CSF and reached a normal range by the 3rd day following head trauma. At that time, the ventricular CSF lactate concentration was still above normal in patients with a poor outcome but had decreased to normal in patients with moderate disabilities or a good outcome. Ventricular CSF pH did not generally correlate with the ventricular CSF lactate concentration in patients under controlled ventilation; however, in a few patients close to death or with ventricular infection, a correlation was noted. Ventricular CSF lactate levels were not related to cerebral blood flow. In this study, profiles of ventricular CSF lactate concentration are defined in relation to the patients' clinical course and outcome. High ventricular CSF lactate concentration is present within 18 hours after severe head injury. Its decrease to normal in the following 48 hours is a reliable sign of clinical improvement; however, ventricular CSF lactate levels that are persistently high or that increase over time indicate the patient's deterioration. Serial assessment of ventricular CSF for acid-base status and metabolites in head-injured patients with a ventricular catheter already placed for ICP monitoring is useful in the evaluation of prognosis and clinical course.

Acidosis, Lactic↗
PubMed1986

[Possibilities of computer use in anesthesia and intensive care medicine].

Today anaesthesiologists are on familiar terms with computers. In fact, computer technology has come to stay especially in the monitoring and documentation of measurement data; no new developments in this field are possible without the aid of computers. Computer-monitored respirators, infusion pumps or anaesthetic vaporizers have been developed and tested in practice, but their use is at present still restricted to a small select circle of specialists. However, their routine use can be expected in the very near future. In the fields of training and communication of knowledge, computers are still in the developmental stage. Although so-called "expert systems" are already in use in certain fields of medicine, their application in anaesthesia remains an exception. Progress in this direction does not really depend so much on the availability of suitable computers--they are in fact already in operation. The crux of the problem will be the readiness of anaesthesiologists and anaesthesists to feed the computers with appropriate programmes and to accept computers as partners in their work and in the field of training.

Anesthesia, General↗
PubMed1986

Neopterin as a prognostic indicator in patients with carcinoma of the uterine cervix.

In vitro, neopterin, a pyrazinopyrimidine compound, is excreted by human monocytes-macrophages after induction by supernatants from activated T-lymphocytes or by recombinant gamma-interferon. In vivo, it represents a noninvasive test for activation of cellular immune reactions. To evaluate the prognostic value of pretherapeutic urinary neopterin levels and of serial neopterin measurements during follow-up in women with cervical cancer, 1088 urine specimens from 186 consecutive patients were analyzed. Clinical assessments were made without knowledge of the results of neopterin assays (a "blinded" assessment). During the observation period (June 1980 to March 1984), 27 relapses, 18 metastases, and 26 deaths were seen. The prognostic significance of pretherapeutic neopterin and other possible prognostic clinical and laboratory parameters was tested by the univariate and multivariate Cox proportional hazards model using a stratification according to stage and surgical treatment. The combination of age at diagnosis, pretherapeutical hemoglobin, leukocyte count, and neopterin was found to predict survival best. On the basis of this result, risk groups were identified exhibiting markedly different survival behavior. A highly significant association was found between serial neopterin measurements and the risk for a relapse, metastasis, or death. The data suggest that urinary neopterin levels might be a useful adjuvant parameter in monitoring women with cervical cancer.

Adenocarcinoma↗
PubMed1985

[Feline infectious peritonitis].

This paper gives a summary of our present-day knowledge concerning etiology, clinical aspects, diagnosis, pathology and pathogenesis of feline infectious peritonitis. Special emphasis is given to the participation of the immune system in the development of lesions. A therapy protocol is proposed and an extensive list of original literature for further study is given.

Animals↗