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Biomedical subjects

J Brock

Publications and source records attributed to J Brock.

At least 73 records · Page 4Linked to original sources
PubMed1993

Semiquantitative determination of IL-1 alpha, TNF-alpha, PDGF-A, PDGF-B, and PDGF-receptor in term human placenta using polymerase chain reaction (PCR).

Eight placenta samples derived from normal term human placenta were examined for the expression levels of Il-1 alpha+, TNF-alpha+, PDGF-A+, PDGF-B+, and PDGF-receptor+ using a semiquantitative PCR protocol. The expressional level of beta-actin was proven to be constant, therefore beta-actin could serve to equilibrate sample size in our procedure. Differences were found in the mRNA levels of IL-1 alpha and TNF-alpha. The expression of PDGF-A, BDGF-B and PDGF-R seemed to be relatively constant in our group of samples. Further investigation and improved quantitative PCR protocols are needed to correlate clinical outcome of pregnancy with cytokine expression at the placental level. +Il-1 alpha (interleukin-1 alpha) +TNF-alpha (tumor necrosis factor-alpha) +PDGF-A (platelet derived growth factor A) +PDGF-B (platelet derived growth factor B) +PDGF-Rezeptor (platelet derived growth factor-rezeptor).

Actins↗
PubMed1993

[Correlation between chronic hyperplastic laryngitis and infection with human papillomaviruses].

Cancer of the larynx is one of the most prevalent tumors of the head and neck, with its prognosis dependent on early diagnosis. A number of authors have now reported a connection between head and neck cancers and infection with human papilloma virus (HPV). A large number of these tumors has been found to be HPV 16/18 positive, with results ranging from 10% to 75% positive. It is currently known that viral infection alone cannot realize an oncogenic potential and there have to be exogenous and/or endogenous factors as well. Further, little is known about the prognosis of epithelial lesions which undergo malignant conversion. The aim of our study was to determine whether the HPV 16/18 content in biopsies of chronic hyperplastic inflammations of the larynx was a prognostic factor for later malignancy. The polymerase chain reaction (PCR) was used to examine 150 laryngeal biopsies from 132 men and 18 women. Additionally, historical data, including information about regular alcohol and nicotine consumption, were examined for an association with HPV 16/18. Three different groups were found to be at risk for developing a carcinoma of the larynx from the 91 patients positive for HPV 16/18 (10 women and 81 men). These included: (1) HPV 16/18 positive patients not exposed to exogenous irritants (6 women and 9 men); HPV 16/18 positive smokers (1 woman and 37 men); (3) HPV 16/18 positive smokers and regular alcohol drinkers (3 women and 35 men). During the 3 1/2 years of our study one woman and one man from the first group developed a cancer of the larynx.(ABSTRACT TRUNCATED AT 250 WORDS)

Alcohol Drinking↗
PubMed1992

Prevalence of cystic fibrosis mutations in the East German population.

A representative multicenter cystic fibrosis (CF) mutation analysis on about half of all known cystic fibrosis patients of the 5 East German Länder is reported. Analyses for 17 mutations, among them Delta F508, R553X, G542X, S549R,N,I, G551D, S1255X, R347P,H, and Y122X, were performed. As expected, the delta F508 mutation in exon 10 of the CFTR gene is the major gene alteration causing CF in our patients. However, in comparison to studies from Western Germany, a significantly lower percentage of just over 60% is found in our patients, resembling data obtained from slavonic populations. The severe phenotype of cystic fibrosis is most frequently associated with homozygosity for the delta F508 mutation. No particular allele association could be found with the intermediate and mild phenotypes of this disease. The next most frequent of the investigated mutations is R553X (13.3% of non-delta F chromosomes) followed by R347P (9.2%) and G542X (4.4%).

Cystic Fibrosis↗
PubMed1992

[Detection of human papillomaviruses (HPV) in laryngeal papilloma. An in situ hybridization study].

Together 35 papillomas of the larynx (8 juveniles, 27 adults) were studied for the presence of HPV-DNA by means of nucleic acid hybridization. The hybridization procedure was carried out "in situ" with biotinylated probes of HPV 6/11 and 16/18 under stringent conditions. The results are shown in Table 1. In all juvenile papillomas we detected HPV 6/11, but we did not find positive signals after hybridization with HPV 16/18, 25 (92.6%) of the examinated adult papillomas were HPV 6/11 positive. The detection procedure of HPV 16/18 was positive twice (11.8%). The results of our studies support the hypothesis of HPV 6/11 in development of larynxpapillomas.

Adult↗
PubMed1992

[Type 6/11 and 16/18 squamous epithelial cancers of the upper respiratory tract and digestive system. An in situ hybridization study].

61 squamous cell cancers (27 laryngeal, 12 hypopharyngeal, 14 tonsillary, 8 tongue) with different keratinization and grading and seven lymph node metastases of HPV 16/18 positive carcinomas were analysed for the presence of HPV-DNA by in situ hybridisation. 65.5% of them were found to be positive. Twelve laryngeal carcinomas (44%), five tonsillary tumours (35.7%), eight tumours of the hypopharynx (66.6%) and three tongue carcinomas (37.5%) were shown to contain HPV 16/18 DNA. The detection rates of HPV 6/11 were lower. 44 of the analysed tumours (72.1%) had a grading G2. 29 of these tumours (65.9%) were HPV positive. Only eight of the patients were no heavy smokers or alcoholic drinkers. One of the lymph node metastases was positive for HPV 16/18. The results indicate that HPV may be involved in the pathogenesis of squamous cell carcinomas of head and neck tumours.

Biopsy↗
PubMed1992

Induction of long-term survival of rat skin allografts by a novel, highly efficient anti-CD4 monoclonal antibody.

The new monoclonal antirat CD4 antibody RIB 5/2, which detects another epitope than those covered by W3/25 and MRC OX35, was tested for its immunosuppressive potency following skin allografting by using strain combinations with different genetic barriers in the MHC and genetic low- or high-responder background. High-dose and long-term therapy of the grafted rats led to a significant delay of the acute rejection (P < 0.01) in the strain combination Wistar Furth-to-BDX as well as in LEW1W-to-LEW1A. No significant prolongation of the mean allograft survival time was obtained for the high-responder rats (LEW1A-to-LEW1W). Cytofluorometric analysis revealed that RIB 5/2 exerts the immunosuppressive activity predominantly by modulation of the CD4 glycoprotein. Furthermore, the dependence of the humoral immune response against the mouse-globulins upon the administered protein quantity could be demonstrated.

Animals↗
PubMed1991

[Use of the Dot-Blot technique in the detection of human papillomavirus(HPV) deoxyribonucleic acid (DNA) in malignant tumors of the oropharynx].

A total of 23 malignant oropharyngeal tumours (palate, tongue, tonsils, pharynx) and two lymph node metastases were analysed for presence of papilloma virus DNA. Thirteen (54.5%) of 22 squamous cell cancers of different koilocytosis and grading were found to contain HPV 16/18 DNA. Only 16.6% (4 cases) were positive for HPV 6/11 DNA. There was no detectable HPV-DNA in the lymph node metastases (Table 1). The control biopsies (19) were negative after hybridisation.

Aged↗
PubMed1991

Differential effect of recombinant tissue plasminogen activator-induced thrombolysis in the central nervous system and systemic arteries.

Recombinant tissue plasminogen activator (rTPA) has been more effective in inducing thrombolysis in laboratory studies of intracranial thrombosis than clinical studies of systemic or coronary thrombosis would indicate. To evaluate this discrepancy, 21 rabbits were subjected to embolic occlusion of the right internal carotid artery (ICA) by retrograde injection of a tin-tagged, 2-hour-old autologous clot through the external carotid artery with angiographic monitoring in the same manner as in a previously reported model. The emboli lodged intracranially at the bifurcation of the ICA in 10 animals and in the cervical ICA in 11 animals. Digital subtraction angiography confirmed total occlusion of the ICA in all animals. Treatment started one-half hour after embolization and consisted of a bolus of 0.5 mg/kg of rTPA followed by an infusion of 1 mg/kg/h for 2 hours. All of the animals with intracranial emboli and 6 of the animals with cervical emboli were treated intravenously. The remaining 5 animals with cervical emboli were treated by intracarotid infusion of the same dose of rTPA. In the intravenously treated group, serial digital subtraction angiography documented thrombolysis in 9 of the 10 animals with intracranial emboli and only 1 of the 6 with cervical emboli. Thrombolysis occurred in 4 of the 5 rabbits with cervical emboli treated with intracarotid rTPA. Intravenous rTPA therapy produced a significantly (P less than 0.01) higher rate of thrombolysis in intracranial as compared to cervical thrombus.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Serum concentration of secretory IgA during pregnancy and in gynaecological diseases affecting glands and mucosas.

Secretory IgA (S-IgA) was measured in serum samples from pregnant women by means of radial immunodiffusion according to Mancini with an antiserum against the secretory component and an S-IgA standard. The results neglect the differentiation in SC, S-IgA, and S-IgM. The study includes S-IgA serum levels during pregnancy and post partum as well as in patients with cervical carcinoma and inflammation of the genital tract. The S-IgA serum levels of pregnant women (2nd and 3rd trimester) and after delivery were increased significantly in comparison to nonpregnant women (p less than 0.01). The S-IgA levels in genital inflammation diseases and cervical carcinoma were only sometimes elevated. Pregnant women, 1st trimester: means = 40.0 mg/l (s = 12.2); pregnant women, 2nd trimester: means = 60.13 mg/l (s = 18.9); pregnant women, 3 rd trimester: means = 73.5 mg/l (s = 17.4); post partum: means = 77.5 mg/l (s = 29.52); cervical carcinoma: means = 41.9 mg/l (s = 17.3); adnexitis: means = 46.46 mg/l (s = 16.8); controls: means = 38.61 mg/l (s = 10.5). In a second part S-IgA could be estimated in serum samples of pregnant women by means of an enzyme-linked immunosorbent assay (ELISA). The levels ranged from 7.1 mg/l to 19.3 mg/l in the 1st trimenon and from 16.8 mg/l to 82 mg/l in the 3rd trimenon (means = 11.72 mg/l; s = 4.419; n = 21 and means = 40.01 mg/l; s = 15.117; n = 60). This increasing was significant too (p less than 0.01).

Adult↗
PubMed1991

Preparation of a neoglycoprotein using a homobifunctional reagent and its applicability for protein blotting and electron microscopy.

A new method for the preparation of a neoglycoprotein (chemically mannosylated bovine serum albumin, D-Man.BSA) is described using the homobifunctional reagent divinylsulphone.D-Man.BSA purified by affinity chromatography on ConA-Sepharose 4B shows microheterogeneity as demonstrated by immunoaffinity electrophoresis with free ConA in the first-dimension gel. The dissociation constant K for the neoglycoprotein-ConA complex has been calculated to be 2.5.10(-5) M. Biotinylated D-Man.BSA is a useful reagent to detect carbohydrate binding proteins of L1210 leukemia cells on blots. The neoglycoprotein labelled with colloidal gold may be used to demonstrate L1210 cell surface D-Man binding proteins by preembedding electron microscopy.

Animals↗
PubMed1991

Detection of mannose-binding proteins on mouse lymphocytes.

D-Mannose influences both the allogeneic stimulation of mouse spleen cells and the induction of cytotoxic T-lymphocytes. At low concentrations (10(-3) -4 x 10(-3) M), D-mannose increases [3H]thymidine incorporation and induction of cytotoxic cells. Higher concentrations lead to an inhibition of the allogeneic response. To test the involvement of mannose receptors, unstimulated and allogeneically stimulated spleen cells were lysed and the proteins electrophoretically separated. After blotting, the D-mannose-binding structures were identified by means of a biotinylated mannose-neoglycoprotein and avidin peroxidase. Two mannose-binding proteins of unstimulated mouse spleen lymphocytes with a molecular mass of 29 and 31 kDa were detected. In vitro allogeneically stimulated spleen lymphocytes show three other mannose-binding proteins with a molecular mass of 53, 65, and 76 kDa.

Animals↗
PubMed1991

[Bronchoalveolar lavage--a diagnostic method in chronic nonspecific bronchopulmonary diseases in childhood? 2. Studies of cellular and humoral parameters in BAL irrigation fluid].

With a view of the pathogenesis of chronic bronchopulmonary diseases the interrelations between infections and evolving defense system are of interest, they are perhaps detectable by means of diagnostic bronchoalveolar lavage. We carried out cytodifferentiation, investigated adenosine deaminase activities and interleukin 1 formation of macrophages, determined immunoglobulin concentrations (secretory IgA), lysozyme, alpha 2-macroglobulin, alpha 1-antitrypsin, albumin. Because the cytodifferentiation yields insight into topical inflammatory reactions, shows diagnostic useful informations in single cases and because it is simple to carry out we can recommend it for each bronchological examination. There were no results specific for any disease group for parameters mentioned above.

Adenosine Deaminase↗
PubMed1991

The monoclonal antibody RIB5/1--a useful completion of the MRC OX-3 and OX-6 haplotype specificity.

The haplotype binding pattern of a new mAb RIB5/1 against RT1 class II antigens on different tissues of inbred rat strains was investigated using the indirect POD-technique and a cytofluorometric analysis. RIB5/1 binds to a polymorphic determinant of the RT1 class II glycoprotein. Unlike MRC OX-3 (and OX-6), RIB5/1 reacts in optimal dilution with the RT1 haplotypes dvl, a, av, g, 1 but not with u. Therefore, the mAb pair MRC OX-3 (OX-6) and RIB5/1 is applicable for specific immunohistological purposes in chimaeric models with these RT1 haplotypes.

Animals↗
PubMed1990

Aortic compliance in hypercholesterolemic Watanabe rabbits compared to normal New Zealand controls.

This study was designed to test the hypothesis that severe atherosclerosis changes aortic compliance. Compliance of a vessel is defined as change in volume per unit change in pressure and is a measure of the stiffness or distensibility of the vascular wall. Part of the energy delivered by the left ventricle in systole is used to propel the blood forward into the aorta and part of it to distend the aorta and major vessels. During diastole, the arterial walls recoil and provide energy for propulsion of blood, thereby making blood flow continuous. It is known that Watanabe hereditary hyperlipidemic rabbits develop severe atherosclerosis beginning at 6 months of age. Compliance of the ascending thoracic aorta was studied angiographically in eight Watanabe hereditary hyperlipidemic rabbits of ages greater than 6 months and six normal lipidemic New Zealand white rabbits of ages greater than 6 months, used as controls. The normal New Zealand white rabbits had an average blood cholesterol of 27.4 mg/dL, SD = 13.8, and a regional compliance in the ascending aorta of 0.004 mL/mm Hg, SD = 0.002, compared to the Watanabe hereditary hyperlipidemic rabbits with a cholesterol of 583.1 mg/dL, SD = 162.7, and a compliance of 0.0022 mL/mm Hg, SD = 0.0015. These are significant differences (p less than .05). In addition, the histopathology of the aorta of the Watanabe hyperlipidemic rabbit compared to that of the controls showed a significant decrease in the number of medial lamellar elastin units, an indicator of the decreased elasticity of the blood vessel wall.

Angiography, Digital Subtraction↗
PubMed1990

Secretory immunoglobulin A in serum of CF patients.

Increased sIgA values were found in CF patients in about 70 per cent (3 studies with 23, 43, 45 CF patients). With higher severity of CF disease (Shwachman score) we could observe higher sIgA levels. Postmortem histological findings and sIgA concentrations correlated well in 13 cases. Determinations of sIgA in serum could serve as parameter for hepatobiliary involvement in CF. Secretory immunoglobulin A (sIgA) is the predominant immunoglobulin of exocrine secretions. In serum large and frequent elevations of sIgA could be found in patients with chronic liver disease characterized by biliary obstruction (3). Slight and irregular elevations were observed in patients with disorders of gastrointestinal tract and of respiratory tract as well as in lactating women (3). Manifestations of the hepatobiliary system in CF will become more important with advancing age and progressively higher life expectancy of CF patients. A simple reliable test for detection of hepatobiliary involvement in CF would be useful.

Biliary Tract Diseases↗
PubMed1990

Diagnosis of cystic fibrosis by means of particle electrophoresis test.

Incubation of polystyrene latex particles with CF serum leads to reduced electrophoretic mobility (EPM) measured by a particle electrophoresis device. About 85% of 50 CF patients, 60 CF heterozygotes and 190 controls (healthy subjects and patients with different disorders) could be identified correctly.

Adsorption↗