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Biomedical subjects

R Berger

Publications and source records attributed to R Berger.

At least 487 records · Page 27Linked to original sources
PubMed1991

Repeated polymerase chain reaction complementary to other conventional methods for early detection of HIV infection in infants born to HIV-infected mothers.

The efficacy of a polymerase chain reaction (PCR) method for early detection of human immunodeficiency virus (HIV) in infants at risk for HIV infection was assessed. The PCR method was added to the routine laboratory test programme in these patients in 1988. PCR was performed in a total of 26 children at risk (age range 2 days to 58 months), including 17 infants born to HIV-infected mothers, who were followed up clinically from the time of birth for a mean period of 23 months (range 6 to 54) in a prospective study. Twelve children were PCR-positive. Eight had AIDS, ARC or symptoms suggestive of HIV infection. All these patients had at least one culture positive for HIV (6/8) and/or one positive serum p24-antigen test (5/8). One child was repeatedly PCR positive, but asymptomatic as well as virus- and antigen-negative. Three asymptomatic children with a single positive PCR result were PCR negative in subsequent tests. Fourteen children with negative PCR did not show clinical or immunological signs suggestive of HIV infection. Their cultures for HIV and antigen-p24 assays were negative. It is concluded that in addition to clinical and immunological parameters PCR is a useful technique for diagnosis of HIV infection in infants born to HIV-infected mothers. However, in case of negative HIV cultures and/or serum p24-antigen tests, single positive PCR results in asymptomatic patients must be interpreted with caution and should be confirmed by repeated tests.

Base Sequence↗
PubMed1991

Constitutive heterochromatin C-band polymorphism in prostatic cancer.

The size of the heterochromatin C-bands on chromosomes has been reported to be associated with some, but by no means all, human malignancies. No studies along these lines have been performed in prostatic cancer. We therefore investigated the size, incidence of inversions, and symmetry versus asymmetry of C-band heteromorphisms on chromosomes 1, 9, and 16 in peripheral blood lymphocytes from 52 prostatic cancer patients and 183 healthy individuals. There were no differences in C-band heteromorphism on chromosomes 1, 9, and 16 between the patients and the controls. Neither were there any differences when patients with early-stage disease were compared with patients with more advanced cancer. Younger (aged less than 70 years) cancer patients had significantly higher frequencies of larger C-bands on chromosomes 1 (p less than 0.01) and 16 (p less than 0.001) than did patients aged more than 70 years at diagnosis. This could indicate a possible relationship between the amount of constitutive heterochromatin on chromosomes 1 and 16 and susceptibility to early development of prostatic cancer but could also result from the age differences between the two patient groups.

Aged↗
PubMed1991

Partial deletion of chromosome 2 in non-Hodgkin lymphoma.

Six patients with non-Hodgkin malignant lymphoma (NHL) in a series of 151 cases showed partial deletion of chromosome 2 when studied cytogenetically. Three had deletions of bands 2p14-p22 and three others had a deletion of bands 2q22-q24 in common. The deletions were associated with other abnormalities in each case and were not associated with a particular subtype of NHL. These deletions are secondary, apparently nonrandom, new abnormalities associated with NHL.

Adult↗
PubMed1991

Studies of BCR rearrangements in Philadelphia-positive acute leukemia.

Five patients with Philadelphia-positive acute leukemia were cytogenetically and molecularly investigated in order to determine the localization of the breakpoints on chromosome 22. Rearrangements of the bcr segment were detected in one case with acute mixed leukemia in a child. Rearrangements in the BCR gene first intron, the so-called bcr2 and bcr3 regions, were detected in two other cases, one with an acute lymphoblastic leukemia (ALL) and one with mixed acute leukemia. No molecular rearrangement could be detected in the last two cases, an ALL and a T-cell acute lymphoblastic leukemia with a t(2;22) translocation.

Acute Disease↗
PubMed1991

Cytogenetic abnormalities in thyroid adenomas.

Cytogenetic investigations using short-term cultures are reported in six thyroid adenomas. Clonal and nonclonal numerical chromosomal changes were present in two tumors. In two of the four remaining, nonclonal numerical and structural abnormalities were observed, whereas only normal karyotypes were found in the other two. Chromosome 10 and 17 were involved in several cases, although no common clonal changes could be detected. The present studies show that thyroid adenomas, benign tumors of an endocrine gland, may have chromosomal abnormalities, as described for other benign tumors.

Adenoma↗
PubMed1991

Origin of the high constitutive level of progesterone receptor in T47-D breast cancer cells.

The T47-D breast cancer cell line constitutively expresses high levels of progesterone receptor (PR). This does not appear to be related to an anomaly in the estrogen receptor (ER) as shown by cloning of the ER cDNA from T47-D cells and its insertion into the expression vector pKSV-10. When transfected into heterologous Cos-7 and L cells this receptor exerts a normal biological activity, stimulating the transcription of a reporter gene only in the presence of estrogen. Moreover, normal estrogen regulation of the transcription of the reporter gene was also observed in situ in T47-D cells. Southern blot experiments showed the presence of four copies of the progesterone receptor gene in T47-D cells. This was related to the existence of four copies of chromosome 11 in these cells. The most likely explanation of the anomalous regulation of progesterone receptor expression in T47-D cells is thus the presence of at least one copy of the PR gene bearing an anomaly in its regulatory region(s).

Animals↗
PubMed1991

Chromosomal localization of two human zinc finger protein genes, ZNF24 (KOX17) and ZNF29 (KOX26), to 18q12 and 17p13-p12, respectively.

Two members of the zinc finger Krüppel family, ZNF24 (KOX17) and ZNF29 (KOX26), have been localized by somatic cell hybrid analysis and in situ chromosomal hybridization to human chromosomes 18q12 and 17p13-p12, respectively. The mapping of ZNF29 together with the previously reported localization of ZFP3 suggests that a zinc finger gene complex is located on human chromosome 17p. ZNF29 maps centromeric to the human p53 tumor antigen gene (TP53). In the analogous murine position, the two mouse zinc finger genes Zfp2 and Zfp3 have recently been assigned to the distal region of mouse chromosome 11, the murine homolog of human chromosome 17. Both human zinc finger genes ZNF24 and ZNF29 are in chromosomal regions that have been noted to be deleted in neoplasms of the lung and of the central nervous system at chromosome 17p and in colorectal neoplasia at chromosomes 17p and 18q.

Animals↗
PubMed1991

Mapping of the gene for X-linked liver glycogenosis due to phosphorylase kinase deficiency to human chromosome region Xp22.

X-linked liver glycogenosis (XLG) is a glycogenosis due to deficient activity of phosphorylase kinase (PHK) in liver. PHK consists of four different subunits, alpha, beta, gamma, and delta. Although it is unknown whether liver and muscle PHK subunits are encoded by the same genes, the muscle alpha subunit (PHKA) gene was a likely candidate gene for the mutation responsible for this X-linked liver glycogenosis as it was assigned to the X chromosome at q12-q13. Linkage analysis with X-chromosomal polymorphic DNA markers was performed in two families segregating XLG. First, multipoint linkage analysis excluded the muscle PHKA region as the site of the XLG mutation. Second, evidence was obtained for linkage between the XLG locus and DXS197, DXS43, DXS16, and DXS9 with two-point peak lod scores Zmax = 6.64, 3.75, 1.30, and 0.88, all at theta max = 0.00, respectively. Multipoint linkage results and analysis of recombinational events indicated that the mutation responsible for XLG is located in Xp22 between DXS143 and DXS41.

Chromosome Mapping↗
PubMed1991

Immortalization of human adult normal prostatic epithelial cells by liposomes containing large T-SV40 gene.

Simian virus SV40 has been widely used to immortalize epithelial cells of mammalian origin. We report here, for the first time to our knowledge, the immortalization of normal adult prostatic epithelial cells in culture by transfection of a plasmid containing SV40 genome with a defective replication origin (SV40 ori-) encapsulated into liposomes. These cells (PNT1) have now been cultured for more than 12 months, and shown to contain the SV40 genome. They express large T protein, present the phenotype of differentiated luminal prostatic cells (positive with antibodies to cytokeratin 18, 19, weakly positive for prostatic acid phosphatase and prostatic specific antigen, negative with anticytokeratin 14 and KL2 antibody). PNT1 cells contain high affinity receptors for dihydrotestosterone. These cells provide a useful tool to study the biology and the pathology of adult prostatic epithelial cells, specially to understand the steps leading to prostatic transformation.

Acid Phosphatase↗
PubMed1991

Tc-99m HMPAO diffuse pulmonary uptake demonstrated in cigarette smokers.

Tc-99m HMPAO, a lipophilic radiotracer used as a brain SPECT imaging agent in the diagnosis of strokes and dementias, is normally localized in the brain and the heart and is excreted through the kidneys (50%) and the hepatobiliary system (14% to 30%). There is no pulmonary localization except in the lungs of smokers. To evaluate pulmonary localization of Tc-99m HMPAO in relation to smoking, 23 patients (aged 27 to 76 years) who were referred for brain imaging studies for strokes or dementias also underwent lung imaging studies immediately following the brain imaging. Anterior and/or posterior lung images were obtained 30 to 45 minutes after IV injection of 15 mCi Tc-99m HMPAO. Diffuse pulmonary uptake was graded semiquantitatively: 3+, pulmonary uptake is equal to or higher than hepatic uptake; 2+, pulmonary uptake is less than hepatic uptake but higher than cardiac uptake; 1+, pulmonary uptake is equal to cardiac uptake; 0, pulmonary uptake is less than cardiac uptake. Each patient's smoking history, including duration and daily consumption, was recorded. Four patients' lung images showed 3+ lung uptake; 6 patients, 2+; 1 patient, 1+; and 12 patients, 0 uptake. Eleven patients with lung uptakes of 3+ to 1+ had a history of cigarette smoking. Twelve patients with lung uptake less than cardiac uptake had no smoking history. Pulmonary distribution of Tc-99m HMPAO is usually negligible in the normal lung. Our results indicate that lung uptake correlates significantly (chi-square = 23, d.f. = 1, P = 0.0001) with smoking history.

Adult↗
PubMed1991

Upper keratinocytes of psoriatic skin lesions express high levels of NAP-1/IL-8 mRNA in situ.

In order to better understand the factors regulating disease promotion and activity in psoriasis (PS), we searched for the in situ expression of mRNA for various cytokines in long-standing PS skin lesions. Specific hybridization with a NAP-1/IL-8 anti-sense RNA probe was keratinocyte associated and yielded strong and specific signals exclusively in the upper layers of the lesional epidermis, but not in uninvolved skin from psoriatic patients or normal skin from non-psoriatics. Interestingly, NAP-1/IL-8 transcripts were focally clustered in a spotty pattern predominantly between the tips of elongated papillae, but were absent in the lower epidermal region and the dermal compartment. We consistently failed to detect appreciable numbers of TNF-alpha and/or IL-6 mRNA-containing cells in psoriatic lesions. These results support the notion that IL-8, rather than IL-6, is an important disease-promoting cytokine in PS. In view of the known in vitro and in vivo effects of IL-8, it is conceivable that this substance greatly contributes to the major pathologic changes seen in psoriatic skin, i.e., keratinocyte hyperproliferation and leucocyte infiltration. In this case, local pharmacologic down-regulation of NAP-1/IL-8 activity could be a promising therapeutic strategy in PS.

Cell Adhesion Molecules↗
PubMed1991

[Molecular genetic aspects of phenylketonuria (PKU)].

In phenylketonuria (PKU) usually there is a defect in the phenylalanine hydroxylase (PAH) gene. Eight restriction fragment length polymorfisms (RFLP's) in the PAH gene together constitute the haplotype. A considerable number of mutations, responsible for the gene defect, some of which are rather frequent, have been described. Here, we present the first results of investigations on the distribution of haplotypes and mutations in PKU patients in the Netherlands. A short literature review is presented.

Haplotypes↗
PubMed1991

Regional mapping of the Batten disease locus (CLN3) to human chromosome 16p12.

The gene for Batten disease (CLN3) has been mapped to human chromosome 16 by demonstration of linkage to the haptoglobin locus, and its localization has been further refined using a panel of DNA markers. The aim of this work was to refine the genetic and physical mapping of this disease locus. Genetic linkage analysis was carried out in a larger group of families by using markers for five linked loci. Multipoint analysis indicated a most likely location for CLN3 in the interval between D16S67 and D16S148 (Z = 12.5). Physical mapping of linked markers was carried out using somatic cell hybrid analysis and in situ hybridization. A mouse/human hybrid cell panel containing various segments of chromosome 16 has been constructed. The relative order and physical location of breakpoints in the proximal portion of 16p were determined. Physical mapping in this panel of the markers for the loci flanking CLN3 positioned them to the bands 16p12.1----16p12.3. Fluorescent in situ hybridization of metaphase chromosomes by using these markers positioned them to the region 16p11.2-16p12.1. These results localize CLN3 to an interval of about 2 cM in the region 16p12.

Chromosome Mapping↗