A novel UV-damaged DNA binding protein emerges during the chromatin-eliminating cleavage period in Ascaris suum

During the early cleavage period of Ascaris suum , chromatin diminution takes place in the somatic founder cells. In the process of chromatin diminution numerous heterochromatic blocks, consisting predominantly of highly repeated DNA, are discarded during mitotic anaphase and are later on digested in the cytoplasm. Very little is known about proteins that are involved in chromatin diminution. We have detected a nuclear protein and purified it to near homogeneity by its preferential binding to UV-damaged DNA. We termed this protein chromatin diminution associated factor 1 (CDAF1), because maximum binding activity per nucleus was observed to develop in 4-8-cell stages, when chromatin diminution occurs for the first time. CDAF1 recognizes cyclobutane pyrimidine dimers in UV-damaged double-stranded DNA. Its binding properties identify CDAF1 as a novel kind of damaged-DNA binding protein. CDAF1 activity is almost not detectable in 1-celled embryos. It increases dramatically during formation of somatic founder cells and persists up to the first larval stage. However, CDAF1 is absent in tissues of adults. These findings led us to suggest that CDAF1 plays a dual role: during the early segregative cleavage period it might be involved in chromatin diminution as a transfactor and act in nucleotide excision repair as an accessory factor throughout embryogenesis.

[Leiomyosarcoma of the spermatic cord with paraneoplastic beta-hCG production]

Leiomyosarcomas of the spermatic cord are very rare tumours, which, in contrast to the rhabdomyosarcoms of childhood, occur almost exclusively in adults. We report the case of a 51-year-old male patient with a metastasizing, pleomorphic leiomyosarcoma of the spermatic cord. The tumour showed paraneoplastic secretion of beta-chain human chorionic gonadotropin (beta-hCG), as was demonstrated by the elevated levels of beta-hCG in serum samples and by immunohistochemistry. Histologically, the tumour was a high-grade leiomyosarcoma which showed an aggressive course with pulmonary metastases appearing 4 months after primary surgery. A concomitant rise in the serum levels of beta-hCG was also noted at this time. A wide spectrum of tumours with a choriocarcinomatous component or paraneoplastic production of beta-hCG has been described, the vast majority being carcinomas. Only two leiomyosarcomas producing beta-hCG have so far been reported. The paraneoplastic production of beta-hCG should prevent confusion with germ-cell tumours, especially teratomas.

CTLA4 codon 17 dimorphism in patients with rheumatoid arthritis

The genetic susceptibility to rheumatoid arthritis is conferred by genes in the human leukocyte antigen (HLA) region on chromosome 6, but additional genes may be involved to determine disease susceptibility. We have studied the distribution of the CTLA4 exon 1 polymorphism (49 A/G) in rheumatoid arthritis. This dimorphism at codon 17 results in an amino acid exchange (Thr/Ala) in the leader peptide of the expressed protein and was analyzed by PCR, SSCP and RFLP in 258 Caucasian rheumatoid arthritis patients and 456 controls. Rheumatoid arthritis patients were characterized by a decreased frequency of homozygotes for the Thr-17 substitution (32% versus 39%) and an overrepresentation of patients heterozygous for the Thr/Ala substitution (54% versus 46%). Gene frequencies for the Ala/Thr substitution differed only marginally from controls. In contrast, analyses of the CTLA4 exon 1 polymorphism with respect to HLA-DRB1*04 revealed significantly more patients with Ala in the homozygous (19% versus 15% controls) or heterozygous state (54% versus 39% controls) and less homozygous for Thr (27% versus 46% controls), with a particular increase of Ala/Ala genotypes among rheumatoid arthritis patients carrying the HLA-DRB1*0401 subtype. Among HLA-DRB1*04 negative rheumatoid arthritis patients, we observed no difference between the allele frequencies of the Ala-17 or Thr-17 substitution.

Codon 17 polymorphism of the cytotoxic T lymphocyte antigen 4 gene in Hashimoto's thyroiditis and Addison's disease

Endocrine autoimmune disorders share susceptibility and resistance factors of the human leukocyte antigen system on the short arm of chromosome 6, but other gene loci also contribute to predisposition and protection. Because the cytotoxic T lymphocyte antigen 4 (CTLA4) alanine-17 encoded by the CTLA4 gene on chromosome 2q33 confers susceptibility to Graves' disease, as well as to type 1 (insulin-dependent) diabetes mellitus, we investigated this dimorphism in the other endocrine autoimmune disorders: Hashimoto's thyroiditis and Addison's disease. We analyzed the CTLA4 exon 1 polymorphism (49 A/G) in 73 patients with Hashimoto's thyroiditis, 76 with Addison's disease, and 466 healthy controls. This dimorphism corresponds to an aminoacid exchange (Thr/Ala) in the leader peptide of the expressed protein. CTLA4 alleles were defined by PCR, single-strand conformational polymorphism analysis, and restriction fragment length polymorphism analysis using BbvI. Patients with Hashimoto's thyroiditis had significantly more Ala alleles than controls, both as homozygotes (22% vs. 15%) and heterozygotes (53% vs. 46%), and less Thr than controls as homozygotes (25% vs. 39%), P < 0.04. The phenotypic frequency for Ala was significantly higher in patients (75%), compared with controls (61%), P < 0.03. Patients with Addison's disease did not differ significantly from controls, but those carrying the suceptibility marker, human leukocyte antigen DQA1*0501, were significantly more CTLA4 Ala17 positive than controls with the same DQA1 allele (P < 0.05). In conclusion, an alanine at codon 17 of CTLA4 confers genetic susceptibility to Hashimoto's thyroiditis, whereas this applies only to the subgroup of DQA1*0501+ patients with Addison's disease.

HLA-DR/DQ/DP interactions in rheumatoid arthritis

Rheumatoid arthritis (RA) is associated with the presence of particular HLA-DRB1 alleles. In order to characterize HLA-DQB1 and/or-DPB1 alleles that contribute to disease susceptibility besides HLA-DRB1 alleles, we have analysed the HLA-DRB1, -DQB1 and -DPB1 polymorphism in 84 RA patients and 135 controls. HLA typing for HLA-DRB1 and -DQB1 alleles was performed using sequence-specific primers in combination with sequence-based typing. HLA-DPB1 alleles were characterized by reverse dot-blot hybridization. Our data confirm the predominant role of the (Q)R/KRAA sequence from AA position 70-74 of the HLA-DRB chain for disease susceptibility. In particular, the lysine (K) substitution at position 71 was highly significantly associated with RA. Analysis of the DQB1 locus revealed no association with RA when linkage disequilibrium between HLA-DRB1 and -DQB1 alleles was considered. In contrast, we observed an increased frequency of HLA-DPB1*0401 among (Q)R/KRAA-positive patients. (Q)R/KRAA-negative RA patients exhibited an overrepresentation of HLA-DPB1*0201 and HLA-DPB1*0601. Rheumatoid factor (RF) production correlated with the presence of the disease-associated (Q)R/KRAA amino acid cassette of the HLA-DRB chain. When HLA-DPB1 allele frequencies were compared between RF-positive and RF-negative RA patients, we observed an increased frequency of HLA-DPB1*0401 among RF-positive RA patients and HLA-DPB1*0201 among RF-negative patients. These results suggest that besides the predominent role of HLA-DR molecules in RA, HLA-DP molecules may have an influence on disease susceptibility and could modulate disease progression. HLA-DPB1*0401 may function in addition to HLA-DRB1*04, whereas HLA-DPB1*0201 and -DPB1*0601 may represent additional risk factors among (Q)R/KRAA-negative RA patients.

HLA-DRB1*04 subtypes are associated with increased inflammatory activity in early rheumatoid arthritis

The sequence polymorphism of HLA-DRB1 molecules in 84 rheumatoid arthritis (RA) patients with early RA has been analysed to evaluate whether particular HLA-DR alleles influence disease progression in the early stage of the disease. Clinical data were analysed by grouping the patients according to disease-associated haplotype combinations (DRB1*04,04/DRB1*04,01/DRB1*04,X/DRB1*01,X) in comparison to patients who did not carry these haplotypes (DRB1*X,X). Our results indicate that patients with early RA who are homozygous for DRB1*04 exhibit an elevated inflammatory activity and an increase of joint affections. In addition, the amino acid polymorphism (QR/KRAA) at position 70-74 seems to affect the production of rheumatoid factors. These results support the role of HLA-DRB1 alleles in the pathogenesis of RA and indicate that patients with particular HLA-DRB1*04 haplotype combinations may require intensified therapeutic interventions in the early stage of the disease to prevent disease progression.

Development of polyarthritis after insertion of silicone breast implants followed by remission after implant removal in 2 HLA-identical sisters bearing rheumatoid arthritis susceptibility genes

We describe 2 HLA-identical sisters who both received silicone breast implants and subsequently developed polyarticular arthritis and neurologic symptoms. In both patients, HLA typing revealed 3 alleles typically associated with rheumatic diseases: HLA-DRB1*0405 and HLA-DQB1*0302 (associated with RA), and HLA-DRB4*01 (associated with mixed connective tissue disease and autoimmune reactions in patients with silicone breast implants. After removal of the implants, rheumatic as well as neurologic symptoms improved dramatically in both patients. One patient achieved complete remission. The other patient, who initially had more progressive disease, retained mild residual symptoms, but had significant improvement in radiological erosions. We believe that our cases support the theories that silicone may act as a triggering factor in genetically susceptible individuals, and that silicone may represent an adjuvant for the development of autoimmune disease. We discuss the possibility that a manifested spectrum of symptoms after silicone exposure might be more specific for a patient's genetic background than unique for silicone.

Value of quantitative DNA analysis in endocrine tumors of the pancreas

BACKGROUND

The diagnosis of malignancy can be difficult in endocrine tumors of the pancreas. Moreover prognostically relevant factors are not available. The aim of this study was to evaluate retrospectively whether the DNA distribution pattern can differentiate between benign and malignant pancreatic endocrine tumors and secondly whether the DNA content of tumor cells gives prognostic information.

METHOD

Image cytometry of paraffin-embedded tumor material of 42 pancreatic endocrine tumors.

RESULTS

In 27 benign endocrine pancreatic tumors (25 insulinomas, 2 benign nonfunctioning endocrine tumors) we could differentiate between 6 diploid, 15 hypotriploid and 6 triploid DNA histograms. In 15 malignant endocrine tumors of the pancreas we could differentiate between 1 diploid, 1 hypotriploid, 9 triploid and 4 hypertriploid tumors. All 4 patients with a hypertriploid tumor died as a consequence of their disease in contrast to only 1 patient with a diploid, hypotriploid or triploid tumor even in case of a nonradical resection.

CONCLUSION

With the help of quantitative DNA measurement a differentiation between malignant and benign endocrine pancreatic tumors is not possible even if the risk of malignancy increases with the DNA content. The DNA content of malignant endocrine pancreatic tumors has an influence on the long-term survival. Hypertriploid tumors have a statistically significantly worse prognosis than diploid, hypotriploid or triploid tumors.

[Traumatic thrombosis of the distal ulnar artery (hypothenar hammer syndrome) in a golf player with an accessory muscle loop around Guyon's canal. Case report]

Arteriography of a 34-year-old golf player with M. Raynaud symptoms of his left hand revealed filling defects in the digital arteries II to IV fingers associated with corkscrew-like configuration of the ulnar artery in Guyon's space. The preoperative workup including 50 clinical laboratory tests searching for connective tissue diseases, vasculitis, and haematological disorders was without pathological findings; more central embolic sources were excluded angio- and cardiologically. MRI-scan demonstrated an anomalous muscle at the level of the hamate hook located underneath the M. palmaris brevis forming a sling around the ulnar artery. Surgery showed the ulnar artery distal to the anomalous muscle dilated with fibrotic thickening and intraluminal thrombosis. The involved A. ulnaris segment was resected and an interpositional vein graft performed. Histopathologic sections showed fibrosis of the arterial wall with intraluminal thrombosis and elastica fragmentation indicating traumatic genesis (hypothenar-hammer syndrome). We suspect intensive golf playing with the grip style and repetitive movements leading to pressure injury of the hypothenar area and the underlying ulnar artery. Contraction of the anomalous muscle belly may have additionally compressed the artery slowing down the arterial flow and accelerating the thrombosis.

Analysis of glycoprotein Ia, Ib, IIb and IV RNA in platelets: quantitative determination using fluorescence-based polymerase chain reaction

The aim of this study was to analyze the RNA level of glycoprotein (GP) receptors in platelets. We have therefore established a quantitative fluorescence-based polymerase chain reaction (PCR) to analyze GP Ia, Ib, IIb, and IV RNA. Isolation of platelet RNA was performed by guanidium isothiocyanate/phenol chloroform extraction. An internal standard consisting of cRNA copies from plasmid pAW109 was included before reverse transcription in each RNA sample and PCR amplification was performed using fluorescence-labeled primers. Subsequently, PCR fragments were separated by gel electrophoresis and quantitation of the GP-specific fragments was done by measuring the fluorescence intensities in comparison to the internal standard. Relative amount of GP RNA/platelet were calculated taking into account the number of platelets used for isolation of platelet RNA and the platelet size as determined by flow-cytometric analysis. Using this method we analyzed the GPIa, Ib, IIb and IV RNA content of platelets in healthy blood donors. In parallel experiments the number of GP cell surface receptors was measured by flow-cytometric analysis and correlated with the GP-specific RNA content. This method may be useful to study the GP-specific RNA content in platelets as well as in other tissues, such as megakaryocytes, especially in patients with congenital or acquired platelet function disorders.

Sensitive determination of the RhD genotype in mixed samples using fluorescence-based polymerase chain reaction

OBJECTIVES

Prenatal determination of the fetal RhD status in pregnancies of Rh-negative (Rh-neg) women by polymerase chain reaction (PCR) on DNA has become of increasing importance. Since determination of the RhD genotype in these cases is usually performed in samples containing both maternal Rh-neg and fetal Rh-neg or Rh-positive (Rh-pos) DNA, the sensitivity and specificity of PCR-based DNA detection are of crucial importance in the diagnosis of the fetal RhD status.

METHODS

We developed a method for RhD typing using the PCR and a fluorescence-based detection method that allows us to determine RhD-pos DNA even if it is mixed with large amounts of Rh-neg DNA.

RESULTS

Using this approach, Rh-pos DNA could be detected in dilutions with Rh-neg DNA of as high as 1 in 10,000 (Rh-pos/Rh-neg). Furthermore PCR amplification could also be carried out on DNA samples from persons with weak (Dweak) or partial (Dcat) RhD antigens.

CONCLUSION

This method will be valuable in prenatal RhD typing after amniocentesis or after the isolation of fetal cells from maternal peripheral blood.

[Treatment of watermelon stomach (GAVE syndrome) with endoscopic argon plasma coagulation (APC). A new therapy approach]

The case of a 74-year-old male patient with a watermelon stomach (GAVE-syndrome: gastric antral vascular ectasia) is reported. The superficial annual mucosa showed the characteristic picture of ectatic capillaries, some of them plugged with fibrin thrombi. Anemia due to chronic blood loss had developed in our patient. The vascular lesions of the antral mucosa were treated endoscopically in three sessions with an argon-plasma-coagulation (APC). Three months after completion of therapy the vascular changes of the antral mucosa had resolved almost completely. In addition no further blood loss had occurred. Many treatment modalities of the watermelon stomach abnormality exist. Nowadays, vaporization of the vascular lesions with the Neodym-Yag laser has widely replaced surgical treatment. The argon-plasma-coagulation uses instead of laser energy conduction of electric energy by ionized argon gas (plasma), which produces coagulation necrosis of tissues. The potential advantages of the argon-plasma-coagulation lie in the limited deep penetration, which reduces the risk of perforation and the symmetric spread of the coagulation effects in the surrounding mucosa. These properties make the argon plasma-coagulation a promising tool for the endoscopic therapy of mucosal lesions of the GI-tract. Further attractive is the low cost of the argon-plasma-coagulation equipment compared with laser devices.

The desire for a son is the father of many daughters: a sex ratio paradox

"This paper investigates the impact of preferences for male offspring to female offspring upon the sex ratio of the population. Asymmetric procreation behaviour of this kind is modelled by assuming that a female's procreation ceases only after at least one son or n daughters are born. It is shown that such asymmetric procreation behaviour has no effect on the sex ratio of the society, but influences rather the growth rate of the population. Finally, problems concerning the interrelationship between the sex ratio, the pattern of procreation, and the marriage regime in stationary populations are investigated."

Genetic complexity of regulatory mutants defective for HLA class II gene expression

MHC (called HLA in man) class II genes play an essential role in cell-mediated immunity. Absence of HLA class II Ag on B lymphocytes is the basis of some congenital immunodeficiencies (CID). We have studied CID by generating transient heterokaryons from cell lines of such patients, and we report that the mutations fall into four complementation groups. In addition, fusions with the HLA class II deletion mutant 721.180 indicate that the genetic defects for each group in HLA class II expression map outside the HLA class II region. A small HLA-DRA promoter fragment is sufficient to drive expression of a reporter gene in normal B cell lines, but expression from the same construct is clearly reduced in mutant cell lines representative of all four complementation groups. This confirms earlier results that indicate defective transcription of HLA class II genes in the class II- CID mutant cell lines. Analysis of proteins that bind to the DRA promoter in nuclear extracts of the mutants suggests that complexes recognizing distinct elements of the DRA promoter may be quantitatively decreased in different mutants. In addition, we show that nuclear extracts from two groups fail to transcribe a DRA promoter construct in vitro accurately reflecting their DRA- phenotypes. In contrast, nuclear extracts from another mutant, RJ2.2.5, transcribe the DRA construct, albeit at a reduced level. Finally, though cell lines from different groups complement each other in vivo, no complementation was observed by mixing extracts for transcription in vitro.

Genetic complexity of regulatory mutants defective for HLA class II gene expression

MHC (called HLA in man) class II genes play an essential role in cell-mediated immunity. Absence of HLA class II Ag on B lymphocytes is the basis of some congenital immunodeficiencies (CID). We have studied CID by generating transient heterokaryons from cell lines of such patients, and we report that the mutations fall into four complementation groups. In addition, fusions with the HLA class II deletion mutant 721.180 indicate that the genetic defects for each group in HLA class II expression map outside the HLA class II region. A small HLA-DRA promoter fragment is sufficient to drive expression of a reporter gene in normal B cell lines, but expression from the same construct is clearly reduced in mutant cell lines representative of all four complementation groups. This confirms earlier results that indicate defective transcription of HLA class II genes in the class II- CID mutant cell lines. Analysis of proteins that bind to the DRA promoter in nuclear extracts of the mutants suggests that complexes recognizing distinct elements of the DRA promoter may be quantitatively decreased in different mutants. In addition, we show that nuclear extracts from two groups fail to transcribe a DRA promoter construct in vitro accurately reflecting their DRA- phenotypes. In contrast, nuclear extracts from another mutant, RJ2.2.5, transcribe the DRA construct, albeit at a reduced level. Finally, though cell lines from different groups complement each other in vivo, no complementation was observed by mixing extracts for transcription in vitro.

[Adjuvant chemotherapy of breast cancer with the CMFV protocol]

Adjuvant CMFV therapy was administered from 1975 to 1984 at the Department of Gynaecology and Obstetrics of the University of Erlangen in 331 patients from a patient population, who underwent an operation with the intention of curing invasive breast cancer. Six cycles of this therapy were administered to 224 women. Only these patients were considered in the evaluation. 538 patients without axillary lymph node metastases and without adjuvant therapy served as reference population. The significance of adjuvant CMFV therapy in relation to the lymph node and menopausal status was investigated in a retrospective analysis. It was shown, that the five-year actual survivals in the group of premenopausal patients with one to three affected lymph nodes and CMFV therapy (n = 60), did not differ significantly from the group of women with premenopausally negative lymph nodes without adjuvant therapy (n = 198) (87.7% versus 88.2%). On the other hand, in the postmenopausal patients, the five-year actual survivals for the corresponding groups were 65.9% and 83.2%, respectively. The difference was significant. The results indicate, that adjuvant CMFV therapy improves the prognosis in premenopausal women, above all in cases with one to three affected lymph nodes. In the postmenopausal patients, a comparable effect could not be demonstrated in this group of patients.

Evaluation of the biological effects of low-molecular-weight heparins

In experiments with a laser thrombosis model in rat mesenteric venules, where laser beams induce defined injuries at the vessel endothelium, antithrombotic potency of low-molecular-weight (LMW) heparins was calculated by the number of laser injuries required to induce vessel occluding thrombi. The antithrombotic effect of various LMW heparins was measured at defined time intervals after subcutaneous application. Simultaneously, rat blood was collected and aXa and aIIa plasma levels were determined by chromogenic substrate assays. The antithrombotic effect calculated in the animal model lasted longer than 48 h after a single subcutaneous heparin injection whereas the anticoagulative effect measured as aXa or aIIa activity was measurable only within the first 6 h after subcutaneous application. LMW heparins showed an antithrombotic effect at dosages where no influence on the coagulation system could be demonstrated.