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Biomedical subjects

A Friedmann

Publications and source records attributed to A Friedmann.

At least 37 records · Page 2Linked to original sources

Management of rhesus isoimmunization by preimplantation genetic diagnosis.

A genetic assay by single blastomere analysis was developed for rhesus (RhD) blood group typing of early cleavage stage embryos. The method, which is based on the simultaneous amplification of an RhD-specific sequence and an internal control in single cells, was applied for the selective transfer of RhD-negative embryos in a family of an RhD sensitized woman and a heterozygote partner. The RhD status of two out of three biopsied embryos was determined. According to their amplified products, both were typed as RhD-negative and transferred to the uterus. Pregnancy was not achieved.

Adult↗

Therapeutic efficacy of vincamine in dementia.

This trial was performed to investigate the therapeutic efficacy of vincamine in the treatment of primary degenerative and vascular dementia. 152 male and female patients aged between 50 and 85 years from two psychogeriatric centers and two nursing homes were initially included in the trial and screened for eligibility. 142 patients completed the trial. Clinical diagnosis was established according to DSM-III-R criteria. Allocation of the patients to the primary degenerative dementia of the Alzheimer type (DAT) group or the multi-infarct dementia (MID) group was based on computed tomography scans, electroencephalographic findings and the Hachinski Ischemic Score. In a 12-week double-blind treatment either 30 mg vincamine or placebo was given twice daily. Confirmatory statistics included item 2 of the Clinical Global Impression (CGI), the total score of the Sandoz Clinical Assessment Geriatric (SCAG) scale, the subscale 'need for help' of the nurse's rating of geriatric patients (Beurteilungsskala für geriatrische Patienten; BGP) and the total score of the Short Cognitive Performance Test (Syndrom-Kurztest; SKT). In addition, data on tolerance and on therapy response were evaluated based on descriptive statistics. The therapeutic efficacy of vincamine was clearly demonstrated by confirmatory analysis as the drug was statistically significantly superior to placebo in all four target variables. The clinical relevance of the outcome was further underlined by the results of the responder analysis of the variables SCAG, BGP and SKT. Based on the results of this trial, it can be accepted that the therapeutic effect of vincamine is superior to placebo in patients with mild to moderate dementia of degenerative and vascular etiologies.

Aged↗

Vasopressin gene related products are markers of human breast cancer.

Immunohistochemical analysis for products of vasopressin and oxytocin gene expression was performed on acetone-fixed tissues from 19 breast cancers representing a variety of tumor sub-types. Studies employed the avidin-biotin complex (ABC) immunohistochemical procedure and utilized rabbit polyclonal antibodies to arginine vasopressin (VP), provasopressin (ProVP), vasopressin-associated human glycopeptide (VAG), oxytocin (OT), oxytocin-associated human neurophysin (OT-HNP), and a mouse monoclonal antibody to vasopressin-associated human neurophysin (VP-HNP). Western Blot analysis was performed on protein extracts of fresh-frozen tissues from 12 additional breast tumors. While VP gene related proteins were not detected in normal breast tissue, immunohistochemistry revealed the presence of VP, ProVP, and VAG in all neoplastic cells for all of the tumor tissues examined. Vasopressin-associated human neurophysin was evident in only one of 19 acetone-fixed tumor preparations. However, Western blot analysis for all 12 fresh-frozen tumor samples showed the presence of two proteins, 42,000 and 20,000 daltons, that were immunoreactive with antibodies to VP, VP-HNP, and VAG. Oxytocin and OT-HNP, by immunohistochemistry, were found to be common to cells of normal breast tissues. For tumors, positive staining for OT was observed in 8 of 18 tumors, while OT-HNP was not detected in any of the tumors examined. These findings indicate that VP gene expression is a selective feature of all breast cancers, and that products of this expression might therefore be useful as markers for early detection of this disease and as possible targets for immunotherapy.

Antibodies, Monoclonal↗

Characterization of pra, a gene for replication control in pSAM2, the integrating element of Streptomyces ambofaciens.

pSAM2 is a genetic element found integrated in Streptomyces ambofaciens (B2) and additionally in a replicating form in two mutants B3 and B4. The presence of the pSAM2 replicating form in these mutants was the result of mutations located on pSAM2 in the pra locus, named pra3 and pra4, respectively. The pra gene is not directly involved in replication, but its inactivation led to the disappearance of the pSAM2 free form; therefore, it was considered as a replication regulator. The pra3 and pra4 mutations were located in the pra promoter and were shown to be point substitutions that increase the promoter strength. The replication regulator role of pra was demonstrated by the fact that its constitutive expression in cells harbouring pSAM2B2, which is normally only integrated, led to the appearance of the pSAM2 replicating form. Northern analysis showed that the pra gene transcript can be detected only for the replicating mutants B3 and B4 and that the three adjacent genes korSA, pra and traSA were transcribed separately. As replication of pSAM2 is not needed for its maintenance but is an indispensable stage of its transfer, the pra gene, described formally as an activator of pSAM2 replication, is patently involved in pSAM2 transfer.

Amino Acid Sequence↗

Comparative analysis of HLA polymorphism at the serologic and molecular level in Moroccan and Ashkenazi Jews.

The Jewish people comprise two major groups, one encompassing the Jews of Ashkenazi (Central and Eastern European) origin and the other including those of Sephardic (Middle Eastern and North African) descent. To the latter belong the Jews of Moroccan stock, who form the largest Jewish subgroup among the non-Ashkenazi population living in Israel. As the members of each of these groups differ in physiognomy and life style, it was of interest to investigate whether these differences are also reflected in their respective HLA compositions. To this end, 132 subjects of Ashkenazi and 113 individuals of Moroccan origin residing in Israel were tested and the results compared with data for other populations made available by the 11th International Histocompatibility Workshop. Comparison between their HLA profiles and those of non-Jews revealed that the Jewish groups in some aspects resembled one another but in others showed disparities. The dissimilarities between the various groups are expressed in terms of gene and haplotype frequencies, as well as in HLA-disease associations (as for example rheumatoid arthritis, erosive lichen planus, primary Sjögren's syndrome, pemphigus vulgaris). However, both Jewish groups shared some unique features with respect to HLA class II allelic frequencies, pointing to a common ancestry.

Adolescent↗

Identical HLA class II alleles predispose to drug-triggered and idiopathic pemphigus vulgaris.

In pemphigus vulgaris, a dermatological autoimmune disease, specific human leukocyte antigen (HLA) class II alleles, DR4 (DRB1*0402) and DRw14 (DRB1*1401, in linkage disequilibrium with DQB1*0503), are thought to be susceptibility genes involved in the onset of the disease. We studied the HLA class II alleles (DQA1, DQB1, DRB1 and DPB1) of 6 patients with pemphigus, in whom the disease was "triggered" by drugs containing sulphydryl or another sulphur-containing group. All patients carried the DRB1*0402 susceptibility allele, and one patient also carried the second susceptibility allele, namely DQB1*0503 (in linkage with DRB1*1401). Bacterial, viral or environmental agents are suspected to trigger the onset of autoimmune diseases. Our study demonstrated the presence in patients with drug-triggered pemphigus vulgaris of the same HLA alleles thought to predispose to idiopathic pemphigus vulgaris. This finding strengthens the notion that these HLA alleles may be true disease susceptibility genes.

Adult↗

Presence of infective Epstein-Barr virus in the urine of patients with infectious mononucleosis.

The presence of Epstein-Barr virus (EBV) in the blood and urine of 20 patients with infectious mononucleosis (IM) was investigated together with the clinical course of the disease, and in 9 patients up to 2-7 months after recovery. EBV DNA, analyzed by the polymerase chain reaction (PCR), was detected in the blood of all 20 patients from the first sample obtained and detected between 3 to 42 days from the beginning of symptoms and up to 2-3 months after recovery. In the urine, EBV DNA was detected in 15 out of 16 (93%) patients in the first sample obtained and detected between 3 to 50 days during the clinical course of the disease. In four patients EBV DNA was detected in the urine up to 3 months after full recovery. Seventeen out of 26 (65%) urine samples including 3 which were obtained 2-7 months after recovery infected B cells as assessed by PCR. Nine out of 12 (75%) urine samples tested induced Epstein-Barr nuclear antigen (EBNA) in the infected B-cell line. In addition to the persistence of EBV in the blood of IM patients, these studies show for the first time the presence of infective EBV in the urine during the clinical course of the disease and up to 7 months after full clinical recovery.

Antigens, Viral↗

Identification of a gene encoding the replication initiator protein of the Streptomyces integrating element, pSAM2.

pSAM2 is an 11-kilobase integrating element from Streptomyces ambofaciens which was previously shown to generate single-stranded DNA during replication, indicating that it probably replicates by a rolling-circle replication (RCR) mechanism. Two separate regions are involved in its replication, one of which was shown to contain the plus origin of replication (ds origin). We report here the study of the second region. Its nucleotide sequence was determined and analysed for open reading frames (ORFs). Three putative ORFs were identified: orf183 (183 amino acids (aa)), orf50 (50 aa), and repSA (459 aa). orf183 is not necessary for replication. The function of orf50 is unknown. repSA is essential for pSAM2 replication; it could encode a protein, RepSA, presenting similarities to the replication initiator proteins (Rep) of elements that replicate by an RCR mechanism. A derivative consisting of repSA, the region containing ds origin, a Streptomyces antibiotic resistance marker, and pBR322, could replicate in Streptomyces, further demonstrating that this ORF encodes the major replication protein of pSAM2. repSA might be co-transcribed with the genes involved in integration and excision of pSAM2.

Amino Acid Sequence↗

Simultaneous detection of three common sexually transmitted agents by polymerase chain reaction.

OBJECTIVE: Human papillomaviruses, herpes simplex viruses, and Chlamydia trachomatis are very common infections of the genital tract. The purpose of our study was to develop a polymerase chain reaction-based assay for the simultaneous detection of these organisms from a single genital swab. STUDY DESIGN: To prove the technical feasibility of a simultaneous polymerase chain reaction assay for these organisms, a mixture of deoxyribonucleic acids extracted from cells infected by these three agents was amplified in the same tube with three different sets of primers corresponding to specific regions of the human papillomavirus genome, the herpes simplex virus 1 and 2 genomes, and the Chlamydia trachomatis plasmid, respectively. Then genital swabs from patients with suspected infection by one or more of these agents were assayed by polymerase chain reaction for the presence of herpes simplex virus, human papillomavirus, and Chlamydia trachomatis independently and simultaneously. Most of the samples were analyzed in parallel by other methods: herpes simplex virus by culture., Chlamydia trachomatis by culture and antigen staining, and human papillomavirus by the filter in situ hybridization method. RESULTS: Analysis of the polymerase chain reaction products amplified from the deoxyribonucleic acid mixture revealed three bands corresponding to the respective amplified region of each microorganism. A total of 391 genital swabs were assayed independently by polymerase chain reaction for the presence of herpes simplex virus (113 samples), human papillomavirus (200 samples), and Chlamydia trachomatis (78 genital swabs and four urethral swabs). Forty-nine were herpes simplex virus positive (47 by culture), 45 were human papillomavirus positive (43 by filter in situ hybridization), and one sample was positive for Chlamydia trachomatis, both by polymerase chain reaction and by culture. Ninety-two of the 391 samples were analyzed simultaneously by polymerase chain reaction for the presence of the three agents. The correlation between the results obtained independently and simultaneously was of the order of 100%: 29 were positive for herpes simplex virus, 16 were positive for human papillomavirus, and one was positive for Chlamydia trachomatis, in one sample we could detect both human papillomavirus and herpes simplex virus. CONCLUSIONS: The polymerase chain reaction simultaneous assay is a quick and efficient way of detecting herpes simplex virus, human papillomavirus, and Chlamydia trachomatis from a single genital swab. This method can greatly simplify the diagnostic procedures in the laboratory.

Base Sequence↗

HLA polymorphism in Moroccan Jewry.

The Moroccan Jewish community living in Israel shows a relatively large genetic distance from other North African Jewish communities. In this work the polymorphism of HLA class I and class II determinants, as defined by serology and oligotyping, is analyzed in 113 healthy unrelated Jews of Moroccan stock. The class I antigens HLA-A1, -B44, and -Cw7 showed the highest frequency, while the most prevalent class II variants were DRB1*0701 and *1104, DQA1*0501, and DQB1*0201 and *0301. HLA A1-B13-DR7, A2-B51-DR10, and A1-B44-DR13 were the most typical three-locus haplotypes. Although the antigen frequency distribution of the Moroccan Jews falls within the Caucasian diversity range, this community has a unique pattern in terms of antigen, gene, and haplotype frequencies. Thus, in the Moroccan Jews DRB1*1305, an allele believed to be the result of a recombination event between DRB1*1301-1302 and DRB1*1101, is represented to a much larger extent than in all the other population groups studied at the 11th IHWS. This allele may therefore be a typical Jewish variant. A particular finding was the high frequencies of HLA-B13, B52, and DR10, alleles common among some Oriental populations. The answer to this enigmatic phenomenon probably must be sought in the tortuous history of this community.

Alleles↗

Do specific pockets of HLA-C molecules predispose Jewish patients to psoriasis vulgaris?

BACKGROUND: Psoriasis vulgaris was reported to be associated with a specific alanine residue at position 73 of HLA-C alleles in Japanese patients. OBJECTIVE: Our purpose was to determine the role of HLA genes in susceptibility to psoriasis vulgaris in the Israeli Jewish population. METHODS: Twenty-eight Israeli patients were analyzed for their HLA class I and II specificities by means of serologic and molecular methods. RESULTS: All patients possessed in their HLA-C antigens an alanine residue at position 73 (p < 0.002). A significantly increased frequency of HLA-Cw6 and of Cw7 was also observed among the patients (p < 0.02). CONCLUSION: Our study clearly shows that alanine in position 73 is significantly associated with psoriasis vulgaris in Jewish patients. Cw6 and Cw7 have a unique antigen-binding pocket containing both alanine at position 73 and a negatively charged aspartic acid at position 9. These residues are most probably important in determining the conformation of the C pocket and in turn the nature of the peptide bound to it. We suggest that this combination confers the highest risk of the development of psoriasis vulgaris.

Alanine↗

Preimplantation diagnosis of cystic fibrosis by simultaneous detection of the W1282X and delta F508 mutations.

W1282X (W) and delta F508 (delta) are the two most common mutations of the cystic fibrosis Israeli population. Patients who are homozygotes (WW and delta delta) as well as compound heterozygotes (W delta) present a severe phenotype of the disease. In the present study, we have developed a polymerase chain reaction (PCR)-based method for the detection of both mutations simultaneously in a single blastomere. Unfertilized human oocytes and single polyspermic blastomeres were subjected to a two-round PCR amplification: a first round of multiplex PCR followed by a second round of nested PCR, done separately at each locus. Clear signals at both loci were obtained in 51% (47/65) of oocytes and 69% (24/35) of blastomeres. The genotype of the single cell analysed was determined by endonuclease digestion of the W products and by heteroduplex formation of the delta F products. This diagnostic system will allow the identification of affected embryos (WW, delta delta, W delta) as well as phenotypically normal carriers (W+, +delta), and therefore may be used for cystic fibrosis preimplantation diagnosis in families who carry either or both mutations.

Base Sequence↗

Serologic and molecular analysis of the HLA system in Israeli Jewish patients with oral erosive lichen planus.

Oral erosive lichen planus is a distinct subtype of the common dermatosis lichen planus. Although the etiology of lichen planus is still obscure, it is known that cell-mediated immune mechanisms and genetic factors underlie its pathogenesis. Previous studies have found an association between lichen planus and HLA-DR3 or DR9 in different population groups. The present work was designed to elucidate, at the serologic and molecular levels, whether and which HLA genes are associated with oral erosive lichen planus in Israeli Jewish patients. A significant association with HLA-DR2 (RR = 4.7; pc < 0.0013) and a decrease in DR4 (RR = 0.3; p < 0.03) among the patients were noted. Oligotyping of DR2 alleles showed the presence of all three common variants (DRB1*1501, DRB1*1502 and DRB1*1601) in the patients, although none of the variants was overrepresented significantly. Three possible explanations for the role of HLA genes in the predisposition to oral erosive lichen planus are discussed. The most attractive theory for the pathogenesis of the disease seems to include the involvement of non-classical HLA genes.

Female↗

Molecular analysis of HLA class II genes in primary Sjögren's syndrome. A study of Israeli Jewish and Greek non-Jewish patients.

In an attempt to define the role of HLA class II genes in predisposition to primary Sjögren's syndrome, patients of two different ethnic groups (Israeli Jews and Greeks of non-Jewish origin) suffering from this disorder were studied. Oligonucleotide genotyping revealed the majority in both groups to carry either DRB1*1101 or DRB1*1104, alleles that are in linkage disequilibrium with DQB1*0301 and DQA1*0501. The high frequency of the two alleles in these SS patients is in contrast with the accepted association of primary SS with HLA-DR3 in Italian and American individuals. Molecular analysis of DQB1 and DQA1 alleles found in American Caucasian and American black SS (or SLE) patients demonstrated high frequencies of DQB1*0201 and DQA1*0501. The fact that the majority of SS patients, across racial and ethnic boundaries, carry a common allele, DQA1*0501, implies its involvement in the predisposition to primary SS. Based on sequence analysis and the computer imaging of the HLA class II molecule structure, a hypothetical model for the role of the DQ molecule in promoting primary SS is proposed.

Alleles↗