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Biomedical subjects

L Braun

Publications and source records attributed to L Braun.

At least 127 records · Page 7Linked to original sources
PubMed1984

[Not Available].

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History, Early Modern 1451-1600↗
PubMed1984

Isozyme profiles of oval cells, parenchymal cells, and biliary cells isolated by centrifugal elutriation from normal and preneoplastic livers.

The fetal liver isozymes aldolase A and pyruvate kinase K increase in livers of adult rats fed a choline deficient-diet containing 0.1% ethionine. Oval cells isolated by centrifugal elutriation from preneoplastic livers of animals receiving the carcinogenic diet contained these fetal forms as well as fetal-adult isozyme hybrids. In contrast, parenchymal cells isolated from the livers of these animals had only aldolase B and pyruvate kinase L, the same isozymes present in parenchymal cells of normal adult rats. Liver homogenates from rats receiving the carcinogenic diet contain lactate dehydrogenase (LDH) 1, LDH 2, and LDH 3 in addition to LDH 4 and LDH 5, which are the forms detected in normal liver homogenates. LDH 1, LDH 2, and LDH 3 are present in oval cells of preneoplastic livers and in biliary epithelial cells of normal livers, but not in parenchymal cells isolated from normal and preneoplastic livers. Cells of biliary epithelium from normal livers also contain aldolase A and pyruvate kinase K, but not the fetal-adult isozymes present in oval cell populations. The results indicate that, in animals receiving this carcinogenic diet, isozyme alterations associated with neoplasia result from the proliferation of a new cell population which contains these enzymes and not from "dedifferentiation" of mature hepatocytes. Furthermore, the data suggest that this new cell population may include a liver stem cell compartment containing cells in transitional states of differentiation.

Animals↗
PubMed1983

Histologic, nuclear DNA, and human papillomavirus studies of cervical condylomas.

Fifty-four cervical condylomatous lesions, with and without nuclear atypia, from 42 women, were studied with the Feulgen microspectrophotometric technique for nuclear DNA quantitation and an immunoperoxidase technique for human papillomavirus (HPV) antigen. All ordinary cervical condylomas (without atypia/dysplasia) had a diploid or polyploid nuclear DNA distribution; 61% had detectable HPV antigen. Among the cervical condylomas with atypia/dysplasia, 55% (17/31) had diploid or polyploid nuclear DNA pattern, and, of these, 59% (10/17) had demonstrable papillomavirus antigen. Fourteen (45%) were aneuploid lesions, 2 of which had a small number of cells with papillomavirus antigen (14%). These findings suggest that the majority of cervical condylomas are related to papillomavirus infection. That lesions with dysplasia, including high degrees of dysplasia, may also exhibit coexistence of papillomavirus infection suggests the possibility of an infectious etiology in the genesis of cervical squamous neoplasia.

Adolescent↗
PubMed1983

Immunoperoxidase localization of papillomavirus antigen in cutaneous warts and bowenoid papulosis.

Using the immunoperoxidase technique and a broadly cross-reactive antiserum which detects infection with any papillomavirus, papillomavirus capsid antigen was demonstrated in 25 of 48 cutaneous papillomas and in two of 38 cutaneous dysplasias. Both positive dysplastic lesions were diagnosed on histopathologic examination as bowenoid papulosis. Antigen-positive cutaneous warts were scattered in all age categories and at all body sites. In addition, there was little variation in antigen expression by morphologic type of wart. Antigen was localized in the nucleus of superficial epithelial cells. The amount of staining was variable, with some warts showing large numbers of stained nuclei. In other warts only isolated cells stained. In both cases of bowenoid papulosis, small foci of positively stained cells were observed. The finding of papillomavirus antigen in two of 21 cases of bowenoid papulosis is suggestive of an etiologic relationship between this lesion and a papillomavirus. An examination of antigen-negative cases of bowenoid papulosis for a papillomavirus genome will be necessary to confirm these results.

Adolescent↗
PubMed1983

The oxidative burst and related phenomena in mouse macrophages elicited by different sterile inflammatory stimuli.

Mouse peritoneal macrophages (MPM) elicited by paraffin oil (PO) or thioglycollate (TG) were compared in their capacity to generate oxidative burst (OB) products such as superoxide ion (O2-) and hydrogen peroxide (H2O2) and lyse target erythrocytes. Strong OB stimulants such as 12-O-tetradecanoyl-phorbol-13-acetate (TPA), opsonized zymosan; and wheat-germ agglutinin (WGA) were found to stimulate O2 and H2O2 production by both PO- and TG-elicited MPM. PO-elicited MPM exhibited a vigorous OB response compared to TG-elicited MPM and showed a higher degree of self iodination in the presence of 125I. Macrophage-mediated cytolysis of 51Cr-labeled red blood cells, following OB stimulation, was revealed by PO-elicited MPM triggered by TPA, opsonized zymosan, WGA, and Concanavalin A. TG-elicited MPM failed to respond to TPA and opsonized zymosan. In the presence of horseradish peroxidase, both PO- and TG-elicited MPM exhibited augmented cytocidal activities upon stimulation with TPA, whereas catalase abrogated the capacity of TPA-stimulated MPM to lyse red blood cells, which may suggest the involvement of H2O2 in the lytic process.

Animals↗
PubMed1983

Papillomavirus in cervical condylomas with and without associated cervical intraepithelial neoplasia.

The aim of this study was to analyze the cytohistologic features of cervical condylomas with respect to the presence of associated cervical intraepithelial neoplasia (CIN) and to evaluate whether or not the prevalence of virus antigen, as detected by immunologic staining with peroxidase-antiperoxidase technique, varies with the histologic appearance of the lesions. In a series of 94 histologically confirmed condylomas of the cervix, almost half (43) had features of CIN grades 1 and 2, corresponding to mild and moderate dysplasia. The prevalence of papillomavirus antigen decreased markedly as the features of associated dysplasia became more severe. The antigen prevalence was 82% in pure condylomas, 32% in condylomas with CIN 1, and 0% in condylomas with CIN 2. The evidence that virus production decreased as the lesion became more severe does not preclude papillomavirus etiology for the CIN lesions. Cells transformed by papillomavirus may be expected to cease production of virus particles even as they continue to harbor the viral genome.

Adolescent↗
PubMed1983

[Cervical condyloma and dysplasia: histological and virological correlation apropos of 100 cases].

Colposcopy and cytology have pointed at the frequency of cervical condylomas with special consideration to flat types. The association condyloma/dysplasia and the behavior of carcinomas in situ as sexually transmitted diseases, suggest that human papillomavirus (H. P. V.) could play a role in cervical cancer. 100 patients have undergone examination for coloscopy, cytology, histology and virology. Dysplastic features were observed in 47 p. 100 and led to classify the lesions in 3 groups according to their importance: condylomas (53 p. 100), dysplastic condylomas (25 p. 100) with predominance of condylomatous pattern, dysplasia (22 p. 100) with a predominant dysplastic pattern. Virologic data were correlated with this classification and demonstrate a dramatic relationship between viral disappearance and the presence of dysplastic features. Virus was found in 83 p. 100 of pure condylomas, 16 p. 100 of dysplastic condylomas and 0 p. 100 of condylomatous dysplasias. Such a phenomenon of viral absence is observed in animal models (malignant transformation of Shope's papilloma): this could be a new argument to suspect the carcinogenic potential of H. P. V. for cervix and external genitalia.

Adolescent↗
PubMed1983

[Significance of tumor size in the prognosis of stomach cancer].

From 1974 to 1982, 261 patients with carcinoma of the stomach were operated upon. Early cancer was found in 4.6%, T4 in 38.3%. Lymph node involvement and distant metastases were discovered at the time of surgery in 68.2% or 14.6% respectively. In 29.9% the operative procedure was defined as curative by the surgeon, in 33.3% as questionable as to the curative effect. The operative mortality rate was 14.9%. 11.5% survived for more than 5 years. With increasing tumour size, operability and survival time diminished significantly.

Adult↗
PubMed1983

[Surgery of elderly patients--evaluation of perioperative mortality].

2127 patients with operations of the stomach, colon, lungs, vascular system, and amputations were analysed with regard to postoperative mortality and age. There was a striking relationship between age and risk in each group of diseases. The perioperative mortality rate rose from 2.3% in the age group under 50 years to 8.5% in patients between 51 and 70 years of age, and to 18.6% in patients older than 71 years. There was no sex related difference. The causes of death in 219 cases were exactly analysed. Cardiac insufficiency, myocardial infarction, cachexia in malignancies, pulmonary embolism, and renal insufficiency were the main lethal complications in elderly patients.

Adolescent↗
PubMed1982

Demonstration of papillomavirus antigen in paraffin sections of laryngeal papillomas.

A papillomavirus antigen has been identified in tissue sections of laryngeal papillomata removed at endoscopic operations. The demonstration of the papillomavirus antigen was achieved using the peroxidase-anti-peroxidase test of Sternberger after a broadly cross-reactive rabbit antiserum to the papillomavirus capsid antigen was incubated with the tissue sections. The antigen was detected in specimens from 7 of 15 patients with juvenile-onset laryngeal papillomas, but could not be demonstrated in the specimens from 6 patients with adult-onset papillomas. In all, 73 biopsy specimens from 21 patients were selected for study; 18% (11/61) of the sections from the juvenile-onset patients and 0% (0/12) of the sections from the adult-onset patient specimens exhibited the papillomavirus antigen.

Adult↗
PubMed1981

Human papillomavirus (HPV) in condylomatous lesions of cervix.

Ninety-seven cervical condylomata classified histologically as flat condyloma (planum), papillary condyloma (acuminatum), and endophytic condyloma were studied by transmission electron microscopy (TEM) and by immunoperoxidase technique (IPT) for the presence of human papillomavirus (HPV) particles and antigen, respectively. Both techniques localized HPV chiefly in nuclei of koilocytotic cells. HPV particles were found in 25% of the cases by TEM and HPV antigen was detected in 48% of the cases by IPT. All cases positive by TEM were also positive by IPT, thus confirming the specificity of the immunological staining. The viral antigen was detected in 56% of 68 flat condylomata, 35% of 26 papillary condylomata, and in none of 3 cases of endophytic condylomata. However, when histiotypes of virus-positive condylomata were controlled for the intraepithelial extent of koilcytotic cells, the prevalence of HPV correlated with the extent of koilocytosis rather than with the histiotype. The immunologic technique will be of value for the further characterization of cervical condylomata and of the relationship between HPV infection and cervical intraepithelial neoplasia.

Adolescent↗
PubMed1981

Hydrolase activities in the rat aorta. V. Comparison to activities in liver and kidney after thyroidectomy and relation to dynamic clearance of circulating low density lipoproteins.

Thyroid hormones influence circulating low density lipoprotein (LDL) levels in humans; they could have an effect on LDL catabolism. Male rats were thyroidectomized (H); half were treated for 7 days with 2 micrograms triiodothyronine/100 g body weight (T) and both groups were compared to controls (C). Aorta, liver, and kidney were assayed for cellular marker enzymes, including lysosomal acid cholesteryl esterase (ACE). Specific activities of ACE (mU/mg DNA; mean +/- SD) were: Aorta, C, 0.19 +/- 0.01; H, 0.16 +/- 0.01; T, 0.21 +/- 0.01; Liver: C, 15.55 +/- 1.49; H, 9.16 +/- 1.54; T, 15.43 +/- 2.28; Kidney: C, 1.70 +/- 0.23; H, 1.04 +/- 0.13; T, 2.08 +/- 0.35. Half lives for injected unmodified 125I-labeled human LDL were 11.5 +/- 0.7 hour in C, 16.2 +/- 3.1 in H, and 12.9 +/- 0.9 in T groups. Fractional catabolic rates (FCR) of LDL in %/hr were 6.5 +/- 0.6 in C; 4.8 +/- 0.5 in H, and 6.0 +/- 0.3 in T. Reductively methylated 125I-labeled human LDL had half-lives of 14.9 +/0 1.4 hour in C and 15.1 +/- 1.6 hour in H and the FCR of this modified LDL was 5.3 +/- 0.5 %/hr in C and 5.2 +/- 0.7 %/hr in H groups. Thus, thyroidectomy results in marked decreases in ACE specific activity of liver and kidney and a marked decrease in FCR and prolonged half-life of non-modified LDL (all P less than 0.05). On the other hand, methylated LDL showed a similarly reduced FCR and prolonged half-life in control and thyroidectomized rats (P less than 0.05). This suggests a major effect of thyroid deficiency on receptor-mediated uptake of LDL in vivo and demonstrates the influence of hormonal status on dynamic clearance and catabolism of LDL.

Animals↗
PubMed1981

Nature et philosophie.

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History, Early Modern 1451-1600↗
PubMed1981

Confirmation of the papillomavirus etiology of condylomatous cervix lesions by the peroxidase-antiperoxidase technique.

The peroxidase-antiperoxidase technique with the use of paraffin sections of 67 cervical biopsy specimens and an antiserum cross-reactive with all papillomaviruses provided immunologic confirmation for the observation that papillomavirus infection of the cervix is not uncommon and that it most often presents as a flat, colposcopically unremarkable lesion. Papillomavirus antigen was detected in 21 or 35 condylomata of the cervix. Antigen-positive nuclei were found in the upper layers of the epithelium. Electron-microscopic examination of five reprocessed antigen-positive sections revealed, in each instance, papillomavirus particles in the nuclei of the most superficial layers of the condylomatous epithelium. The viral antigen was not detected in dysplasia, carcinoma in situ, or invasive carcinoma.

Animals↗