1/51. CD4 depletion in hiv-infected haemophilia patients is associated with rapid clearance of immune complex-coated CD4 lymphocytes.The predominant immunological finding in hiv haemophilia patients is a decrease of CD4 lymphocytes during progression of the disease. Depletion of CD4 lymphocytes is paralleled by an increase in the proportion of immune complex-coated CD4 cells. We examined the hypothesis that the formation of immune complexes on CD4 lymphocytes is followed by rapid clearance of immune complex-coated CD4 lymphocytes from the circulation. In this study, the relationship of relative to absolute numbers of immune complex-loaded CD4 blood lymphocytes and their association with viral load were studied. Two measurements of relative and absolute numbers of gp120-, IgG- and/or IgM-loaded CD4 lymphocytes were analysed in hiv and hiv- haemophilia patients, with a median interval of approx. 3 years. Immune complexes on CD4 lymphocytes were determined using double-fluorescence flow cytometry and whole blood samples. viral load was assessed using NASBA and Nuclisens kits. Whereas the proportion of immune complex-coated CD4 lymphocytes increased with progression of the disease, absolute numbers of immune complex-coated CD4 lymphocytes in the blood were consistently low. Relative increases of immune complex-coated CD4 blood lymphocytes were significantly associated with decreases of absolute numbers of circulating CD4 lymphocytes. The gp120 load on CD4 blood lymphocytes increased in parallel with the viral load in the blood. These results indicate that immune complex-coated CD4 lymphocytes are rapidly cleared from the circulation, suggesting that CD4 reactive autoantibodies and immune complexes are relevant factors in the pathogenesis of AIDS. Relative increases of immune complex-positive cells seem to be a consequence of both an increasing retroviral activity as well as a stronger loading with immune complexes of the reduced number of CD4 cells remaining during the process of CD4 depletion. The two mechanisms seem to enhance each other and contribute to the progressive CD4 decrease during the course of the disease.- - - - - - - - - - ranking = 1keywords = sample (Clic here for more details about this article) |
2/51. Survey of amniocentesis for fetal sex determination in hemophilia carriers.A study was designed to determine whether there is an increased risk of complications when amniocentesis for fetal sex determination is performed on hemophilia carriers. questionnaires were sent to 112 medical centers providing this service in the united states, and to 19 outside the united states. Responses were received from 76% of the centers in the united states. Data on 11,819 taps were obtained. Only 75 taps (0.64%) were performed for the indication of hemophilia. The frequency of fetal deaths in the general sample (1.84%) was not significantly different from that in the subsample of hemophilia carriers (1.33%). The results of this survey correspond very closely to data from a National Registry on amniocentesis for various indicaions in such variables as the number of taps needed for diagnosis, color of the fluid obtained, and number of dry taps. Carrier women who had bleeding problems during the monitored pregnancy are described. The problems might have been related to the amniocentesis in three women. It is calculated that only 2-4% of hemophilia carrier women who might have amniocentesis are utilizing the service.- - - - - - - - - - ranking = 2keywords = sample (Clic here for more details about this article) |
3/51. An alloantibody recognizing the FVIII A1 domain in a patient with CRM reduced haemophilia A due to deletion of a large portion of the A1 domain dna sequence.We report the development of a FVIII inhibitor in a patient with severe, cross reacting material reduced (CRM(R)) haemophilia A. The level of factor viii antigen (FVIII:Ag) measured by ELISA using anti-C2 monoclonal and alloantibodies was 1.9 U/dl. This baseline FVIII:Ag level was increased to 8.3 U/dl after administration of DDAVP. The anti-FVIII inhibitor titer was 2.9 Bethesda U/ml. dna analysis showed a large deletion of the FVIII gene from exon 4 to 7, corresponding to amino acid residues 111-317 included within the A1 domain. The size of the gene deletion was approximately 28 kb. 5' and 3' breakpoints were identified by sequencing in intron 3 and intron 7, respectively. FVIII mRNA was detected in the patient's peripheral lymphocytes and the deletion spanning exon 4 to 7 was confirmed at the rna level. immunoprecipitation experiments using 125I labeled A1, A2 and light chain demonstrated that the inhibitor reacted only with the 54 kDa A1 domain. The inhibitor activity was more than 95% neutralized by A1 domain polypeptide. Our findings suggest a close relationship between the inhibitor epitope and the specific gene deletion with regard to the pathogenesis of the inhibitor in this patient.- - - - - - - - - - ranking = 0.062154219197213keywords = size (Clic here for more details about this article) |
4/51. De novo factor viii gene intron 22 inversion in a female carrier presents as a somatic mosaicism.The intron 22 inversion represents the most prevalent factor viii gene defect in severe hemophilia a, accounting for about 40% of all mutations. It is hypothesized that the inversion mutations occur almost exclusively in germ cells during meiotic cell division by intrachromosomal recombination between 1 of 2 telomeric copies of the Int22h region and its intragenic homologue. The majority of inversion mutations originate in male germ cells, where the lack of bivalent formation may facilitate flipping of the telomeric end of the single x chromosome. This is the first intron 22 inversion that presents as a somatic mosaicism in a female, affecting only about 50% of lymphocyte and fibroblast cells of the proposita. Supposing a post-zygotic de novo mutation as the usual cause of somatic mosaicism, the finding would imply that the intron 22 inversion mutation is not restricted to meiotic cell divisions but can also occur during mitotic cell divisions, either in germ cell precursors or in somatic cells. (Blood. 2000;96:2905-2906)- - - - - - - - - - ranking = 0.062154219197213keywords = size (Clic here for more details about this article) |
5/51. Postpartum acquired hemophilia (factor viii inhibitors): a case report and review of the literature.Pathologic inhibitors of blood coagulation as a cause of postpartum acquired hemostatic failure are rare. Since 1937, 96 cases of postpartum factor viii (FVIII) inhibitors, including the current case, have been reported. Suspicion for the diagnosis of this condition is often low. We report a case of postpartum FVIII inhibitor formation in a 24-year-old woman who developed intermittent postpartum bleeding that resulted from the inhibitors she formed to FVIII. A unique form of therapy was used in treatment of her disorder. She did not respond to conventional surgical or medical management of her bleeding until Autoplex T (Baxter Healthcare, Glendale, CA), an activated prothrombin complex concentrate (aPCC) was used. The literature concerning acquired hemophilia is reviewed, and new therapeutic medical advances are emphasized.- - - - - - - - - - ranking = 0.062154219197213keywords = size (Clic here for more details about this article) |
6/51. Disseminated "mycobacterium genavense" infection in patients with AIDS.We describe 18 patients with advanced hiv infection, most of whom had a chronic illness characterised by fever, diarrhoea, and massive loss of weight. biopsy and necropsy samples revealed abundant acid-fast microorganisms in intestines, liver, spleen, lymph nodes, and many other tissues, which did not grow on solid media, although limited growth was observed in liquid blood cultures. Using primers complementary to bacterial 16S rRNA we amplified dna sequences from tissue and leucocyte extracts and from blood-culture bottles. The sequences obtained were unique and suggest that the microorganism is a new member of the genus mycobacterium, for which we propose the name "mycobacterium genavense". Disseminated infection with "M genavense" should be considered in the differential diagnosis of hiv-infected patients with extreme immunosuppression, wasting, and fever.- - - - - - - - - - ranking = 1keywords = sample (Clic here for more details about this article) |
7/51. Prenatal exclusion of haemophilia A and carrier testing by direct detection of a disease lesion.A novel mutation was detected in the factor viii gene of a sporadic case of severe haemophilia A. The lesion, a CGA-->TGA transition, converts Arg 795 to Term and adequately accounts for the severe phenotype observed. PCR/direct sequencing was used to confirm the carrier status in the mother. Exclusion of haemophilia A in an at-risk pregnancy was then achieved by demonstration of the absence of this lesion in fetal dna from a chorionic villus sample. The mutation was also detectable by chemical cleavage of mismatch (CCM), which both confirmed the prenatal diagnosis and established the carrier status of the proband's sister. This example therefore serves to illustrate the potential of direct gene analysis in sporadic cases of haemophilia A and/or in families uninformative for known RFLPs.- - - - - - - - - - ranking = 1keywords = sample (Clic here for more details about this article) |
8/51. Serological response and detection of viraemia in acute hepatitis c virus infection.The serological response during acute hepatitis c virus (HCV) infection was examined by enzyme-linked immunosorbent assay (ELISA) in sequential serum samples from 13 haemophiliacs following their first exposure to factor viii concentrates contaminated with HCV. The commercially available C100-3 peptide and a new 22 kDa recombinant protein (p22) encoded by the nucleocapsid region of the viral genome were used for antibody detection, whilst a nested polymerase chain reaction (PCR) method was used for the detection of viraemia. In addition, eight sporadic cases of acute HCV infection were studied. The results in haemophiliacs demonstrated that seroconversion to the C100-3 antigen occurred in only one-third of the patients within 12 weeks of disease onset, but all of the patients had a diagnostic serological response to p22 during this phase of the disease. The new test was positive in all the sporadic cases at a time when the commercially available test was negative. Although PCR offers a sensitive method for the detection of recent HCV infection, the complex methodology makes it unsuitable for diagnostic laboratories. The new ELISA test with p22 may therefore have a useful diagnostic role in acute disease.- - - - - - - - - - ranking = 1keywords = sample (Clic here for more details about this article) |
9/51. Surgical excision of hemophilic pseudotumor of the ilium.The iliac hemophilic pseudotumor is a rare complication of hemophilia occurring in 1-2% of patients with factor viii or factor ix deficiency. It is frequently disabling and life threatening. This report presents a comparative study of postoperative results of two cases of hemophilic pseudotumor of ilium. One patient undergoing partial resection showed a favorable postoperative course, whereas the patient with complete resection of the pseudotumor died of postoperative bleeding and sepsis. Studies on the postoperative results of these two cases indicate that careful preoperative consideration of tumor size and degree of infiltration is of the utmost importance in operative management. Early excision of tumors eliminates the possibility of endogenous infection. Even partial resection of huge tumors, leaving the lateral wall intact for compression, can promote recovery of functions.- - - - - - - - - - ranking = 0.062154219197213keywords = size (Clic here for more details about this article) |
10/51. prenatal diagnosis in a haemophilia A family by both factor viii activity and antigen measurements.With the advent of molecular biology techniques prenatal diagnosis in haemophilia A is generally being performed by first trimester chorionic villus sampling followed by the dna analysis using various polymorphic markers of factor viii gene. Here we report antenatal diagnosis in a haemophilia A family performed in the second trimester by measuring both factor viii:C and factor viii:Ag in the fetal blood sample.- - - - - - - - - - ranking = 1keywords = sample (Clic here for more details about this article) |
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