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J Mallolas

Publications and source records attributed to J Mallolas.

At least 37 records · Page 2Linked to original sources

Implications of the FMR1 gene in menopause: study of 147 Spanish women.

OBJECTIVE: To evaluate the relationship between the FMR1 premutation and premature ovarian failure (POF) in the Spanish population and the possible incorporation of this test in gynecological procedures for women with POF or early menopause (EM). DESIGN: Clinical and molecular genetic study. Ninety-eight premutated and six full-mutated carriers of fragile X syndrome and 43 women with POF were studied by polymerase chain reaction and Southern blot analysis for the CGG repeat expansion in the FMR1 gene. RESULTS: Among premutated carriers, 12.2% (12 of 98) presented with POF, and 15.3% (15 of 98) presented with EM. Neither POF nor EM was observed in any of the six full-mutated women. Two women of 43 from the POF population (4.65%) were carriers for the CGG premutation in the FMR1 gene. No correlation between CGG expansion size and age at menopause was found. A biased paternal origin of the premutation and a high twinning incidence was found in all premutated women, whether they had POF or not. CONCLUSIONS: Our data support the hypothesis that the FMR1 gene is one of the genes associated with POF and EM. Analysis of the CGG expansion in the FMR1 gene may be justified in women with POF and EM until the real role of the FMR1 premutation is determined.

Adult↗

[Fragile X syndrome: premature ovarian failure. Preimplantation and preconception genetic diagnosis].

Although it is generally accepted that women who are carriers of the premutation of the fragile X syndrome (FXS) show no pathological clinical features, several studies have shown that they have a higher incidence of premature failure of their ovaries (early menopause) than the general population. However, when women who are carriers of the complete mutation are studied, no relation is seen between the two conditions. All women who are carriers of the premutation of the FMR1 gene should be informed that they have a greater possibility than the general population (10-15 times) of having an early menopause. Pre-implantation genetic diagnosis (PGD) is a technique used in diagnosis, based on genetic analysis of an embryo obtained by in vitro fertilization (IVF) and subsequently transferred to genetically healthy viable embryos. Preconception genetic diagnosis is based on the genetic study of an ovule before fertilization and subsequent IVF of healthy ovules. The methodology is similar in both cases. Genetic study of FXS is especially difficult because of the large number of CGG repetitions in affected. Often indirect diagnosis has to be made. Both diagnoses have a series of evident advantages over prenatal diagnosis. There is no pregnancy present so the stress and emotional trauma of VIP (voluntary interruption of pregnancy) is avoided. However, it should be pointed out that there are technical drawbacks regarding genetic analysis and the need to resort to IVF in fertile couples.

Cytogenetic Analysis↗

[Influence of highly active antiretroviral therapy on the evolution of AIDS-associated Kaposi's sarcoma].

BACKGROUND: To evaluate the highly active antiretroviral therapy (HAART) in the Kaposi's sarcoma evolution. PATIENTS AND METHOD: Retrospective analysis of a cohort of 126 HIV infected patients suffering from Kaposi's sarcoma with or without HAART. Clinical evolution, immunological status (CD4+ cell count) and response to therapy (HIV-RNA plasma viral load and human herpes-8 virus determination). RESULTS: All patients without HAART died and the cumulate probability survival (SD) among those who received HAART was 2.078 (74) days. The CD4+ count at baseline in the HAART group was 130 (125) * 106/l and the HIV-RNA viral load was 196,818 (244,195) copies/ml while at the moment of the clinical response was 235 (209) * 106/l CD4 + and 2,629 (6.444) copies/ml, respectively. CONCLUSION: HAART prolongs survival in HIV patients suffering from Kaposi's sarcoma. There is a clear relationship among clinical response, HAART and immunological recovery.

Adult↗

Impact of switching from human immunodeficiency virus type 1 protease inhibitors to efavirenz in successfully treated adults with lipodystrophy.

We prospectively followed 20 consecutive patients with human immunodeficiency virus type 1 (HIV-1) with viral loads of <200 RNA copies/mL. These patients had been treated with 2 nucleoside reverse transcriptase inhibitors and > or =1 HIV-1 protease inhibitor for > or =3 months; they developed body changes consistent with lipodystrophy and requested they be switched from protease inhibitor to efavirenz. At baseline and every 3 months, we assessed the following: body mass index, waist-to-hip ratio, regional fat thickness (assessed by sonography), fasting total and high-density lipoprotein cholesterol, triglycerides, glucose, insulin, CD4(+) cells, and viral load. At baseline, hypertriglyceridemia (> or =200 mg/dL) was present in 17 (85%) patients, hypercholesterolemia (> or =200 mg/dL) in 14 (70%), and impaired fasting glucose (> or =110 mg/dL) in 8 (40%); CD4(+) T cells were 280x10(6) cells/L (range, 64-942x10(6) cells/L). HIV-1 RNA had been at <200 copies/mL for a median of 14 months (range, 3-24 months). Six months after switching to efavirenz, there was a reduction in triglyceride levels (a decrease of 31%; P=.03) and fasting insulin resistance index (a decrease of 28%; P=.03), but total and high-density lipoprotein cholesterol and glucose did not change. Waist-to-hip ratio decreased from 0.92 to 0.87 (P=.06). Subcutaneous fat thickness did not change. CD4(+) cells remained stable (363x10(6) cells/L; range, 102-741x10(6) cells/L; P=.65). Nineteen patients (95%) had HIV-1 RNA levels that remained at <200 copies/mL. Although CD4(+) response and viral suppression remained preserved after 6 months of switching from protease inhibitor to efavirenz, the benefits of this approach on the evolution of lipodystrophy were limited, and our findings do not support its routine recommendation to treat lipodystrophy.

Adipose Tissue↗

Dose-finding study of once-daily indinavir/ritonavir plus zidovudine and lamivudine in HIV-infected patients.

BACKGROUND: Strategies for treatment of HIV need to be considered in terms of combining potency, safety, and convenience of dosage. However, regimens including once-daily protease inhibitors are not yet available. We have performed a pilot study to determine an indinavir/ritonavir (IND/RTV) regimen for once-daily dosing, by monitoring plasma levels. METHODS: Antiretroviral-naive HIV-infected adults were eligible. Therapy was zidovudine/lamivudine 1 pill twice daily plus IND/RIT (liquid formulation) 800/100 mg twice daily with food. At 4-week intervals, plasma levels were measured and dosage of IND/RIT switched to 1000/100 mg daily and then 800/200 mg daily. If 12-hour minimum concentrations (Cmin12h) of IND were too low (<0.1 microg/ml) with IND/RIT 1000/100 mg once daily in the first half of the patients, it was planned to switch directly to 800/200 mg once daily in the other half. RESULTS: In all, 27 patients were recruited. Mean baseline CD4+ lymphocyte count was 107 x 106/L (range, 4-623 x 106/L). Eleven patients (40%) discontinued the study medication within the first 4 weeks due to clinical progression (n = 3) or grade 1-2 RTV related side effects (n = 8). Nine patients (group A) switched from 800/100 mg twice daily to 1000/100 mg once daily and then to 800/200 mg once daily. Seven patients (group B) switched directly to 800/200 mg once daily. At week 32, viral load was <5 copies/ml in 15 of 16 patients (94%). RTV levels were always <2.1 microg/ml. The mean and 95% confidence interval for IND Cmin and Cmax in microg/ml was: using IND/RTV 800/100 mg twice daily (n = 16) 1.4 (0.5-2.3) and 6.7 (4.4-9.1), respectively; using IND/RTV 1000/100 mg once daily (n = 9) 0.18 (0-0.41) and 8.6 (3.3-14), respectively; and using 800/200 mg once daily (n = 16) 0.38 (0-0.9), and 7.5 (0.8-14.8). For all 16 patients who received IND/RTV 800/100 mg twice daily, the Cmin value for IND was >/=0.1 microg/ml. Conversely, IND Cmin was <0.1 microg/ml in 4 of 9 receiving 1000/100 mg once daily but in only 1 of 16 receiving 800/200 mg once daily. CONCLUSION: Once-daily regimen of IND/RIT is feasible and deserves further evaluation in larger randomized trials. Liquid formulation of RIT was not well tolerated by our antiretroviral-naive patients despite lower than suggested doses.

Adult↗

Rare variants in the promoter of the fragile X syndrome gene (FMR1).

Fragile X syndrome, the most common form of familial mental retardation, is mainly caused by the expansion of an unstable region of CGG repeats in the 5' untranslated region of the FMR1 (Fragile X Mental Retardation-1) gene. Molecular tools to detect an abnormal CGG expansion in FMR1 include Southern blot hybridization and PCR amplification. Southern blotting with the StB12.3 probe and Eco RI/Eag I double digestion is widely used as a routine test for fragile X syndrome diagnosis in laboratories around the world. A patient with mental retardation of unknown origin showed absence of digestion for Eag I due to a -149C-->G substitution in the CpG island of the FMR1 gene, which destroys that restriction enzyme site. Screening for other changes around that region also detected a -154insGGC in a patient with a phenotype highly suggestive of fragile X syndrome but without CGG expansion. Expression studies did not show any abnormal changes in FMR1 function. In summary, we have identified two different changes (a C to G substitution at -149 and a GGC insertion at -154) in the promoter of the FMR1 gene. These are the first variants described in the promoter of the FMR1 gene.

Adolescent↗

Detection of the fragile X syndrome protein for the evaluation of FMR1 intermediate alleles.

Molecular screening programs in mentally retarded individuals have been performed in several populations worldwide. One finding has been an excess of FMR1 intermediate alleles in a population with learning difficulties. However, other published reports with similar characteristics did not corroborate those previous results. In order to contribute additional data from our population, we studied 563 patients affected with nonspecific mental retardation (MRX) that did not present a CGG expansion in the FMR1 gene and 208 individuals as a control population. Forty MRX patients presented alleles within the intermediate range. Among them, one case showed a pattern of expression of the FMR1 protein (FMRP) concordant with a fragile X syndrome case with an intermediate allele/full mutation mosaicism, although it was not detected by Southern blot analysis. Statistical analysis was performed again showing no statistically significant difference regarding the intermediate allele frequency in the MRX and control populations. This finding is in agreement with the hypothesis that the incidence of intermediate FMR1 alleles in MRX populations does not seem to be higher than in control populations, and it emphasizes the importance of FMRP detection as a diagnostic tool for fragile X syndrome.

Alleles↗

Loss of heterozygosity in renal and hepatic epithelial cystic cells from ADPKD1 patients.

Autosomal dominant polycystic kidney disease (ADPKD) is one of the commonest genetic diseases in man, affecting 1:1000 individuals in the Caucasian population. It is caused by mutations in the PKD1 or PKD2 genes. Recently, controversial data regarding the mutational mechanism underlying cyst initiation have been reported: genetic analyses have shown that second somatic mutations may lead to cyst formation (detected as microsatellite loss of heterozygosity, LOH, and point mutations), but immunohistochemical studies show strong immunoreactivity for polycystin in some cysts. In order to further characterise this matter we have analysed 211 cysts from seven different patients for LOH, we have detected a 13.3% LOH for PKD1. This loss was specific to PKD1 as no LOH was detected when other chromosomal regions were studied. Whenever linkage analysis has been possible, it has been proved that the lost allele corresponded to the wild-type. Our data supports previous results in the two-hit theory for ADPKD due to the large number of cysts studied. ADPKD would occur through a recessive cellular mechanism. The probability of cyst development would depend on the probability of mutation in the second allele. The different phenotypical expression of the same mutation reported in ADPKD could be due to the different tendency of inactivation in the second allele in each individual.

Cells, Cultured↗

Intravenous cidofovir for compassionate use in AIDS patients with cytomegalovirus retinitis. Spanish Cidofovir Study Group.

We report the compassionate use of intravenous cidofovir for the treatment of cytomegalovirus retinitis in 51 patients with AIDS who were receiving highly active antiretroviral therapy (HAART). After a median of 9 doses, 49 patients showed no retinitis activity. However, treatment was stopped in 17 patients because of adverse reactions and in 5 patients for other reasons. Two deaths were considered related to the drug. Iritis developed in 21 patients (41.2%), a frequency higher than that reported during the pre-HAART era. Patients with iritis had median CD4 cell counts-both at nadir and at the initiation of cidofovir therapy-approximately 3 times higher than those for patients without iritis (P=.003 and P=.05, respectively). Our study confirms the efficacy of cidofovir therapy for AIDS-associated cytomegalovirus retinitis. Our data suggest that the risk of iritis may be higher for patients with better immunological status, probably because of their enhanced ability to mount an inflammatory response.

AIDS-Related Opportunistic Infections↗

Antineutrophil antibodies associated with ulcerative colitis interact with the antigen(s) during the process of apoptosis.

BACKGROUND: Cell death by apoptosis seems to be an important mechanism for translocation to the cell surface of a variety of intracellular components capable of inducing autoantibody production. AIMS: To identify the cellular location of antigen (Ag)-antineutrophil cytoplasmic antibodies (ANCA) in non-apoptotic human neutrophils, and to assess if ANCA associated with ulcerative colitis reacts with neutrophil antigen(s) during neutrophil apoptosis. The cellular distribution of Ag-ANCA in apoptotic neutrophils was also investigated. METHODS: Sera from 18 ulcerative colitis patients known to be positive for perinuclear IgG-ANCA (titre > or =1/320), as assessed by indirect immunofluorescence (IIF), were analysed by immunofluorescent confocal laser scanning microscopy. ANCA were identified with fluorescein isothiocyanate (FITC) and tetramethylrhodamine isothiocyanate (TRITC) in non-apoptotic and apoptotic neutrophils, respectively. Apoptotic and non-apoptotic DNA was labelled with FITC and propidium iodide, respectively. Cycloheximide was added to polymorphonuclear leucocyte culture to induce apoptosis. RESULTS: Three patterns of scanning laser immunofluorescence microscopy in non-apoptotic neutrophils were observed with respect to cellular ulcerative colitis associated ANCA distribution: (1) diffuse nuclear localisation (16.7%); (2) nuclear localisation in the nuclear periphery (50%); and (3) mixed nuclear and cytoplasmic localisation (33.4%). In all sera ANCA fluorescence colocalised almost completely with apoptotic DNA, with persistence of a diffuse and intense fluorescence. No significant changes in ANCA titres were found in non-apoptotic neutrophils. CONCLUSIONS: The antigen(s) of ANCA associated with ulcerative colitis seems to be localised in most cases in the neutrophil nucleus. The almost identical colocalisation of ANCA and apoptotic cleaved DNA suggests that intracellular DNA redistribution during neutrophil apoptosis may play a role in antigen exposure to the immune system and ANCA production in ulcerative colitis.

Antibodies, Antineutrophil Cytoplasmic↗

Single-strand conformation polymorphism analysis in the FMR1 gene.

The fragile X syndrome is due to an expansion of the CGG trinucleotide repeat in the FMR1 gene and hypermethylation of its 5' upstream CpG island in about 95% of the cases. The remaining 5% of cases correspond to other molecular alterations in FMR1 gene such as partial or complete deletions, or point mutations within the coding sequence. We selected 31 patients with clinical manifestations of fragile X syndrome, scoring 16 or more in Hagerman's checklist, but without the CGG expansion. We performed single-strand conformation polymorphism analysis using a nonradioactive technique (silver staining) and we detected six anomalous migrations that, by sequence analysis, corresponded to six nucleotide changes. We screened two different populations (control and fragile X) for these changes, and concluded that they correspond to five new polymorphisms within the FMR1 gene and to one possible synonymous mutation.

Fragile X Messenger Ribonucleoprotein 1↗

[Disseminated cryptococcosis in patients with AIDS. Prognostic factors of poor outcome].

BACKGROUND: The objectives of this study were to analyze the changes in the incidence of cryptococcal disease in the last 10 years (1987-1997) and to assess the factors of poor prognosis in HIV-1 infected patients. PATIENTS AND METHODS: Clinical records of HIV-1 infected patients diagnosed with cryptococcal infection from June 1987 to December 1997 at Hospital Clinic i Provincial in Barcelona, Spain, were examined. An univariate and multivariate analysis of the predictors of poor outcome was performed. RESULTS: Sixty clinical records were analyzed. The number of cases per 100 exposed patients per year decreased from 1991 to 1993 and, afterwards, decreased again from 1996. Fifty patients had a resolution of clinical symptoms, 17 out of this 50 patients (34%) had a relapse. Factors associated with a higher risk of relapse were a positive blood culture and cryptococcal antigen title in cerebrospinal fluid above 1/1.024. CONCLUSIONS: The decrease in the number of cases of cryptococcal infection coincides with the broad use of triazole antifungal drugs for oral candidiasis (1990-1991) and, afterwards, with the initiation of highly active antiretroviral therapy (1996). The best predictors of relapse are a positive blood cryptococcal culture and a high titter of cryptococcal antigen.

AIDS-Related Opportunistic Infections↗

Isolation of pig mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase gene promoter: characterization of a peroxisome proliferator-responsive element.

Low expression of the mitochondrial 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) synthase gene during development correlates with an unusually low hepatic ketogenic capacity and lack of hyperketonaemia in piglets. Here we report the isolation and characterization of the 5' end of the pig mitochondrial HMG-CoA synthase gene. The 581 bp region proximal to the transcription start site permits transcription of a reporter gene, confirming the function of the promoter. The pig mitochondrial HMG-CoA synthase promoter is trans-activated by the peroxisomal proliferator-activated receptor (PPAR), and a functional response element for PPAR (PPRE) has been localized in the promoter region. Pig PPRE is constituted by an imperfect direct repeat (DR-1) and a downstream sequence, both of which are needed to confer PPAR-sensitivity to a thymidine kinase promoter and to form complexes with PPAR.retinoid X receptor heterodimers. A role of PPAR trans-activation in starvation-associated induction of gene expression is suggested.

Amino Acid Sequence↗

Biochemical phenotype and its relationship with genotype in hyperphenylalaninemia heterozygotes.

The molecular detection of heterozygotes for hyperphenylalaninemia is difficult due to the large number of mutations in the PAH gene. For this reason, various indexes that measure plasma concentrations of phenylalanine (Phe) and tyrosine (Tyr), as an expression of Phe metabolizing capacity, have been used for the detection of carriers for mutations in the PAH gene. In this study, we contrast the biochemical and the molecular data in order to know if this is an accurate method. Familial genetic analysis of the PAH gene in 93 parents of hyperphenylalaninemia patients allows the study of the biochemical expression of the different mutant alleles. Molecular study was performed by SSCP and DGGE analyses of PAH genes, and plasma amino acid analysis by ion-exchange chromatography. Then the biochemical and molecular data were compared by the Student t test. The results found show a relationship between the severity of PKU/HPA mutations in the PAH gene and their biochemical phenotype (Phe/Tyr, Phe2/Tyr) as an expression of the residual enzymatic activity. The study adds further information about the prevalent Mediterranean allele mutations.

Female↗