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Duchenne and Becker muscular dystrophy (DMD/BMD) are recessive X-linked neuromuscular diseases produced by allelic mutations in the human dystrophin gen. In the present study we determined the 14-deletion prone exons by multiplex PCR in 24 no related venezuelan patients with clinical diagnosis of DMD/BMD. We found 37% of intragenic deletions of which 77% were located at the "hot spot" deletion region that includes exons 44 to 55. The present study show that deletion frequency observed in venezuelan patients resembles some Asian populations and is lower than that observed in Europe and North America. The explanation of the low frequency detected in our patients is beyond the present study, but it is likely that different mutations, ocurring at other regions of the gene is determining a molecular heterogeneity of the DMD/BMD disease in Venezuela.

Since the beginning of cytogenetics, there has been a constant improvement of chromosomal culture and banding techniques. In 1976, Yunis described a high chromosomal resolution technique (HRC), that permits the detection of subtle chromosomal abnormalities. The present work, reports the results obtained when HRC was applied to the study of chromosomal abnormalities in patients with high risk of such. The study comprised 434 specimens of venous blood and 182 bone marrow aspirates. The samples were classified according to the presuntive diagnoses. The highest frequency of chromosomal abnormalities, was found in blood samples from patients with physical deformities with or without mental retardation (22.22%), followed by mental retardation autism and/or fragile X chromosome (13.66%), and in couples with reproductive disorders (5.8%). In bone marrow, the most frequent abnormalities corresponded to patients with chronic myeloid leukemia (78.43%), acute lymphocytic leukemia (62.10%), acute myeloide leukemia (61.9%), myelodisplastic syndromes (43.7%) and chronic lymphocytic leukemia (14.2%). The present results stress the need to apply the HRC technique when the probability of minute chromosomal abnormalities is high.

Results from an epidemiological study of congenital malformations (CM) realized at Pedro Garcia Clara Hospital from march 1989 to december 1992 are presented. Malformation was defined as all external or internal morphological defects that could be clinically diagnosed at birth. In all births, incidence and type of CM, birth condition, sex, weight, number of pregnancies and maternal ages were analyzed. Moreover, in live births from march 1989 to august 1991, were analyzed: the type of childbirth presentation, maternal residence place, paternal age, maternal and paternal occupation and school education, parental consaguinity, previous spontaneous abortions, other malformed in the family and exposition to physical agents, medicaments, vaccines, acute and chronical diseases and vaginal bleeding in the first trimester of pregnancy. The control group were children born during the same day and sex matched as the malformed children. The incidence of CM was 23.4 per 1000 total births. Most frequent malformations were principally minor or feasible of satisfactory treatment. Major malformations were Central Nervous System anomalies, specially, neural tube deffects and Down syndrome. Only maternal age, type of childbirth, other malformed members in the family and medicaments exposition were statistically significant. Our results confirm the importance and utility of CM epidemiology monitoring.

The results of a retrospective analysis of newborn population with neural tube defects (NTD) occurred in the Hospital Pedro Garcia Clara at Zulia State for the period 1982-1988, sex, birth condition, maternal age, number of pregnancies and mother's mean permanency of time in the zone, were studied. The control sample were children who were born the same day and of the same sex as the malformed children. By that period, the NTDs occupied the first place as morbidity caused for congenital malformations. NTDs had an incidence rate of 2.28 out of thousand total of births and can be considered one of the highest reported in the country. The major rate, 5.5 per 1000 was observed in 1986. The frequency of NTDs was higher in stillbirths and females. There were no differences between NTDs and controls in relation with maternal age and number of pregnancies in the mother. There was a heterogeneous geographical distribution with high concentration of cases of NTDs in Bachaquero and Mene Grande. The permanency of the NTDs's mothers was greater than that the controls' mothers. According to this investigation, it is suggested a necessity for more profound studies in order to identify and clarify some possible environmental conditions that could explain the present findings.

We have quantified the soluble class I antigen (sHLA) secretion by peripheral blood lymphocytes of 26 multiple sclerosis (MS) patients. Thirteen of them were in a stable phase of the disease, 6 on relapse and 7 suffered from a progressive MS. sHLA secretion was reduced in the presence or absence of phytohemagglutinin in patients with either active or stable MS, being normal after stimulation with a monoclonal antibody anti-CD3. In MS patients, lymphocyte proliferation and immunoglobulin secretion were found to be similar to those of 29 healthy blood donors who comprised the group of controls. These results reflect systemic anomalies in the cell activation process in MS, which seem to be independent of the disease activity. Whether these alterations are specific to MS or are common to other inflammatory CNS diseases remains to be elucidated.

Chronic myelocytic leukemia is a particular subtype of leukemia characterized by increased myeloid precursor cells. It has been associated with the presence of the Philadelphia chromosome, described by Nowel and Hungerford in 1960, as a deletion of part of the long arm of a G group chromosome, the 22 chromosome. The present work reports the chromosomal abnormalities observed in 39 patients with chronic myelocytic leukemia, studied at the Genetic Unit, in the Faculty of Medicine of Zulia University, during the period from 1987 to 1991. Sixty per cent of the patients showed different abnormalities, such as 8 trisomy, t (8;22), and in the remaining 15%, no chromosomal changes were detected. The patients with t (9;22) as the only abnormality, had less relapses and longer survival. The clinical course of 50% of the patients with normal karyotype was similar to those with t (9;22) as the only abnormality; the other 50% had an accelerated course with frequent relapses and early death. The present findings confirm that the presence of the Philadelphia chromosome as the only karyotypical abnormality, is indicative of better prognosis, and its association with other chromosomal changes predicts a more accelerated course that will probably require a more aggressive treatment.

We have studied the intrathecal synthesis of soluble class I antigens (sHLA), reflected by the index IH = (CSF sHLA/serum sHLA)/(CSF albumin/serum albumin), in multiple sclerosis (MS). IH was increased in patients in relapse, but normal in patients in remission; these findings show that there is a high lymphocyte activation within the central nervous system in patients with clinically active MS.

Two phosphatidylinositol-specific phospholipases C (PI-PLC) have been purified from human spleen. PI-PLCm represents the main activity detected in the membrane, while PI-PLCc is the main activity present in the cytoplasm. PI-PLCm can be resolved into two peaks of activity of high Mr (60,000-70,000) and low Mr (16,000-18,000). High salt concentration ((NH4)2SO4, 2M) dissociates the high Mr form yielding the low molecular form and increasing the specific activity. The same effect of dissociation and potentiation of the activity is observed when membranes solubilized by n-octyl glucoside are subjected to the high voltage conditions of an isoelectric focusing run. The purified Pi-PLCm has a Mr of about 18,000 when analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis or gel filtration and a basic pI (9.0-9.2). Purified PI-PLCc has a Mr of 57,000 (sodium dodecyl sulfate-polyacrylamide gel electrophoresis or gel filtration) and a slightly acid pI (6.2). Other characteristics of both enzymes, such as cations dependence, substrate specificity, optimum pH, and kinetic parameters, are also discussed.

In this work we have quantified soluble class I histocompatibility antigens (s-HLA) and beta 2-microglobulin (beta 2 m) in sera of HIV+ or HIV- mothers at delivery and in cord blood sera of their newborn children. The results obtained for beta 2 m show that cord blood sera of newborn children have higher concentrations than their mothers, implying that most of the beta 2 m in the newborn is self-produced as described previously. s-HLA serum concentrations in the newborn children are significantly lower than in their mothers or in age-matched controls. Moreover, HIV+ mothers have significantly higher serum concentrations than HIV- mothers or an age-matched control group. These results suggest that s-HLA does not cross the placental barrier.

A solid immunoassay for the detection of protein tyrosine kinases has been developed. It is based on the binding of the synthetic polypeptide poly(Glu.Na,Tyr) 4:1 to microELISA wells, where the phosphorylation reaction takes place in the presence of ATP and enzyme. The phosphorylated tyrosine residues produced in the reaction are finally detected, in the same well, by means of an ELISA using monoclonal antiphosphotyrosine antibody, peroxidase-labeled goat anti-mouse IgG antibody, and substrate. The amount of protein tyrosine kinase activity present in the sample is proportional to the color at 492 nm developed in each well.

The aim of this work is to reevaluate the hypothesis of the existence of a possible genetic control of nondisjunction of chromosome 21. The population under study was the families trisomy (TLI) as diagnosed in the Medical Genetic Unit of LUZ from 1971 to 1988. The control population was the families of 418 individuals with no apparent genetic pathology (CON), approximately matched in age with the patients. The frequency of consanguineous unions in parents (UCPM), maternal grandparents (UCAM) and paternal grandparents (UCAP) of both patients and controls was determined. The results indicated that UCPM was significantly greater in TLI than CON while the UCAM and UCAP were more frequent in CON. The coefficient of consanguinity in parents of TLI was three times greater than in parents of CON. The results of this investigation suggest that the consanguinity should be considered another risk factor for the nondisjunction of chromosome 21 and it is independent of maternal age and support the hypothesis that there exists an autosomal recessive gene that, in the homologous state, results in a predisposition toward nondisjunction of chromosome 21 in the first mitotic division.

A case is reported in which a comprehensive program of hyperbaric oxygen (HBO), surgical debridement and reconstruction, and continuing medical management resulted in complete and sustained closure of an extensive perineal Crohn's lesion refractory to conventional medical and surgical management. It is emphasized that in this case healing occurred in the setting of previous removal of all diseased intestinal tissue and only with the combined use of all three treatment modalities. HBO may be a useful adjunct in the therapy of large nonhealing perineal lesions post-proctocolectomy in patients who are unresponsive to metronidazole or to immunosuppressant therapy or who experience limiting side effects from continued medical therapy.

sHLA are soluble class I antigens produced by lymphocytes on early activation. We have studied the sHLA index IH = (CSF sHLA/serum sHLA)/(CSF albumin/serum albumin), which reflects the intrathecal synthesis (ITS) of sHLA in 23 intravenous drug abusers with central nervous system (CNS) HIV infection. Their mean IH value was increased and directly correlated with ITS of IgG against HIV when the total group of patients was studied; however, 8 of them, who suffered from concomitant tuberculous meningitis, had a decreased IH. The relationship between this index, blood-brain barrier (BBB) function, and HIV and tuberculous infection was also studied. We consider IH an index of lymphocyte activation within the CNS. Its decrease in patients with CNS HIV infection may reflect the presence of a meningeal opportunistic infection due to Mycobacterium tuberculosis.

The case of a patient with severe anaerobic infection, a brain abscess, is presented. The causative organism was a penicillinase-producing, clindamycin-resistant strain of Bacteroides melaninogenicus. Treatment with adequate doses of penicillin G failed. Findings in this case suggest caution when basing therapy on the untested assumption that B. melaninogenicus is routinely susceptible to penicillin and clindamycin therapy.

Paracoccidioides brasiliensis (ATCC 60885) produces conidia that, when plated in enriched media and incubated at 21-25 degrees C, give rise to a yeast-form variant (YRT) (ATCC 46678). The virulence of this variant for BALB/c mice has been compared with that of the yeast and conidia produced by the parent isolate. Adult female mice were inoculated intravenously with 10(7) viable cells of YRT or yeast, or 5 x 10(5) viable conidia. Mice were weighed weekly, and three mice were sacrificed at 1, 2, 3, 4 and 8 weeks post-inoculation and their organs weighed and prepared for determination of viable counts (colony forming units; c.f.u.). Animals infected with yeast cells or with conidia exhibited little weight loss in comparison with that seen in the YRT-infected mice which began to lose weight 1 week post-challenge. Organ weights increased in the YRT group, while the changes in the remaining two groups were minor. The c.f.u. from these organs also increased in the YRT-infected mice, whereas the infection in the yeast-and conidia-infected mice was self-limiting. A proportion (16.6%) of the YRT-infected animals died during the observation period. Conversely, no deaths occurred in the remaining groups. These results indicate that the YRT variant possesses increased virulence.

A healthy young adult is described in whom acute erosive esophagitis developed four weeks after undergoing splenectomy and receiving six units of blood because of trauma. Cytomegalovirus inclusion bodies were identified in esophageal mucosa, and cytomegalovirus was cultured from blood and throat. Within three weeks, the patient's anticytomegalovirus antibody had increased four-fold. The patient was initially anergic and had a titer of antinuclear antibody of 1:10,240. His symptoms and histopathologic findings disappeared over five weeks, and his immunologic abnormalities were partially corrected. It is suggested that cytomegalovirus was the primary cause of gastrointestinal disease in this nonimmunocompromised patient.

Incubation of Paracoccidioides brasiliensis conidia at 20-25 degrees C (RT) results in two types of colonies, mycelial (M) and yeast (YRT). A study of the latter colonies was undertaken. Conidia were plated in complex (BHI) and chemically-defined media (CDCM), with and without fetal calf serum (FCS). Incubation was carried out at 21 degrees C for 4 weeks. The mean number of YRT colonies was approximately 18.5% on BHI agar. Selected YRT colonies were transferred to liquid CDCM, incubated 7 days at 21 degrees C and transferred to solid media; YRT appearance was preserved in 95% of the colonies if media were FCS-supplemented; otherwise, most colonies reverted to the M form. When FCS was replaced by bovine albumin or by alpha-globulin, 63% and 68% respectively of the colonies obtained after plating YRT cells, became mycelial. Comparative morphologic studies of both YRT and yeasts grown at 37 degrees C suggested that there were no major differences between these two types of yeast cells when size and budding were taken into consideration. The results indicate that in this particular variant, dimorphism is not exclusively temperature-dependent.

Saponins were extracted from quinoa (Chenopodium quinoa Willd, Kancolla variety) by refluxing with a methanol-water (4:1) mixture. Once the methanol was evaporated, the remaining residue was treated following Honerlagen and Tretter's method with only slight modifications. The extract was then hydrolyzed with 12N sulfuric acid in a 1:1 dioxane-water system at 110 degrees C for 1.5 hr. The sapogenins were extracted with chloroform, concentrated and some microliters (equivalent to 121 mg of quinoa) were spotted, against an oleanolic acid standard, on a silicagel g plate and developed with a chloroform-acetone-benzene (80:20:10; v/v) mixture. The spots were located by iodine vapor, and the band whose Rf was similar to that of the oleanolic acid, was scraped into a glass column, eluted with chloroform, dried out, dissolved in 1 ml of glacial acetic acid, treated with 4 ml of (1:1; v/v) sulfuric acid:glacial acetic acid mixture, heated in a water bath at 60 degrees C for 25 minutes, cooled and taken to the spectrophotometer where it was read at a wave length of 527 nm against a reagent blank. Under the same conditions, the oleanolic acid employed as a standard showed a linearity in the range of 60 to 480 micrograms. The oleanolic acid percentage has been determined (0.269 +/- 0.025) in quinoa, and the content of saponins estimated using a conversion factor found by gas chromatography and expressed in the following relationship: % Saponin = (8.5204) x (% oleanolic acid) The sapogenin extract obtained - analyzed by this method - showed an error of 10.7% in relation to its gas chromatography determination.

Soluble major histocompatibility complex class I molecules (sHLA) present in human serum can be resolved by gel filtration into two different peaks with an apparent molecular mass of about 200 kDa (30% of the total) and 50-60 kDa (60%-70%). The serological analysis of the peaks shows that A or B specificities can only be detected in the 200 kDa peak while both are recognized by the monomorphic W6/32 monoclonal antibody (mAb) and anti-beta 2-microglobulin mAb. Such sHLA (non HLA-A or -B) molecules are released from human spleen membranes upon incubation at 37 degrees C and have been purified by affinity chromatography with mAb W6/32 bound to Sepharose. The molecular mass analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the sHLA (non HLA-A or -B) and of the classical HLA-A or -B antigens still bound to the membranes and purified from the same membranes after detergent solubilization does not show a significant difference, indicating that sHLA do not represent proteolytic fragments of the classical HLA-A or -B antigens. The presence of sHLA (non HLA-A or -B) has also been detected in the supernatants of lymphocyte cultures and increases dramatically upon stimulation by mitogens. The effect of pokeweed mitogen, phytohemagglutinin, Staphylococcus aureus Cowan strain and phorbol 12-myristate 13-acetate on the secretion of sHLA has been studied. The molecular mass of the secreted sHLA (detected using [14C]leucine) is compared with the classical transmembrane proteins.

Pulmonary shunt calculated by the Berggren method is commonly used as an indicator of pulmonary function. Although there is usually a good correlation between the shunt and the A-aDO2, other physiologic parameters involved in the shunt equation may significantly alter pulmonary function. The purpose of this study is to show the contribution of the PVO2 and a--v diff to the shunt equation. Data from eight selected patients with A--aDo2 values ranging from 300 to 395 torr and calculated shunts ranging from 6 to 35% were selected for this purpose. In patients with significant changes in PVO2 and a--v diff, the A--aDO2 is more reliable as an indicator of pulmonary function than is the calculated shunt.