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Biomedical subjects

C Mazza

Publications and source records attributed to C Mazza.

At least 19 recordsLinked to original sources
PubMed2004

Lack of interaction between a polymorphism in the dopamine D2 receptor gene and the clinical features of migraine.

The purpose of this study was to evaluate whether a particular genotype of the dopamine D2 receptor (DRD2) gene would affect the clinical features of migraine. In a group of 118 migraineurs (55 migraine with aura and 63 migraine without aura patients), we tested the association of the biallelic C/T NcoI DRD2 polymorphism with several characteristics of the disease. Genotype and allele frequencies resulted similarly distributed in migraine with aura and migraine without aura patients (chi2 = 1.58, P = 0.45 and chi2 = 0.09, P = 0.77, respectively). The different DRD2 genotypes (C/C, C/T and T/T) had no significant effects on age at onset of migraine, presence of premonitory phenomena, frequency of headache attacks, associated symptoms, psychological features and quality of life of our migraine patients. The results of our study do not support a role for the DRD2 gene in modifying the clinical features of migraine.

Adult↗
PubMed2003

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy syndrome: time to review diagnostic criteria?

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is an autosomal-recessive syndrome defined by two of the following conditions: chronic mucocutaneous candidiasis, hypoparathyroidism, or Addison's disease. Other autoimmune conditions may be associated, such as hypothyroidism, hypogonadism, insulin-dependent diabetes mellitus, chronic active hepatitis, pernicious anemia, vitiligo, alopecia, biliary cirrhosis, and ectodermal dysplasia. APECED is caused by mutations in the autoimmune regulator gene, mapping to 21q22.3. We report on three patients whose clinical and molecular features challenge the currently used diagnostic criteria for APECED. AR presented at 15 yr of age with a history of recurrent infections and mucocutaneous candidiasis. He is now 21 yr old, and no other signs or symptoms of APECED have appeared to date. DR presented at 7 yr of age with hypocalcemia and a prolonged Q-T interval on the electrocardiogram. He also had minor facial dysmorphisms and mild mental retardation. Serum calcium levels were low, PTH levels were undetectable, and hypoparathyroidism was therefore diagnosed. All other biochemical, immunological, and endocrinological tests were normal. DR is now 8 yr old with no other signs or symptoms of APECED. ST presented at 14 yr of age for alopecia aerata and pitted nail dystrophy and goiter. Thyroid function was normal in the presence of thyroid-specific antibodies. No other signs or symptoms of APECED have appeared to date. Genetic analysis revealed a typical mutation (R257X) on a single allele in both AP and DR; in ST, heterozygosity for a novel mutation (V484M) involving one of the zinc fingers of the plant homeodomain of the protein was found. The finding of a typical APECED mutation in two patients presenting with one isolated major clinical APECED feature and of a novel mutation in a patient presenting with atypical features of APECED onset suggests that the time might have come for updating the diagnostic criteria of this syndrome.

Adolescent↗
PubMed2001

Monocytes from Wiskott-Aldrich patients differentiate in functional mature dendritic cells with a defect in CD83 expression.

Wiskott-Aldrich syndrome (WAS) is an X-linked disorder characterized by congenital thrombocytopenia and progressive deterioration of the immune function. Dendritic cells (DC) are key effectors in the induction of specific immunity and are highly specialized in antigen uptake and subsequent migration to draining lymph nodes. DC were generated in vitro from circulating monocytes from ten WAS patients characterized by a different disease score. Immature DC showed similar morphology and membrane phenotype, as compared to normal DC. In chemotaxis assay, immature DC had a reduced migration in response to MIP-1alpha/CCL3, but efficiently endocytosed the macromolecules FITC-dextran and FITC-albumin. Upon terminal differentiation with LPS or CD40 ligand, the acquisition of a mature surface phenotype was variably achieved among WAS patients, with increased expression of CD80, CD86 and DC-LAMP. In contrast, the expression of CD83 was usually low. A defective up-regulation of CD83 was also observed in the lymph node from one WAS patient, whose DC stained positively for DC-LAMP. Mature DC from all the patients tested, but one, significantly migrated in vitro in response to MIP-3beta, a finding confirmed in vivo by the detection of HLA-DR/DC LAMP-positive cells in secondary lymphoid organs. When tested in MLR assays, both immature and mature WAS DC induced allogenic T cell proliferation in a manner comparable to control DC. Collectively these results suggest that, although many functional activities of WAS DC are essentially similar to normal DC, subtle and selective alterations of DC differentiation were also observed, with reduced migratory activity of immature DC and defective CD83 expression upon maturation.

Antigen-Presenting Cells↗
PubMed2001

Henoch-Schönlein purpura in Wiskott-Aldrich syndrome.

Wiskott-Aldrich syndrome (WAS) is a rare immune deficiency disease. Sialophorin glycosylation is defective in WAS. Although it is not very common, renal involvement including IgA nephropathy (IgAN) was reported. Abnormal glycosylation plays a key role in the pathogenesis of IgAN. We present an 8-year-old boy with WAS who had recurrent episodes of Henoch-Schönlein purpura with renal involvement following upper respiratory tract infections. His renal function did not deteriorate. Both IgAN and WAS have glycosylation defects, but there must be some other factors (genetic and environmental) to explain their rare association.

Humans↗
PubMed2001

Crystal structure of the human nuclear cap binding complex.

The heterodimeric nuclear cap binding complex (CBC) binds to 5'-capped polymerase II transcripts. It enhances the efficiency of several mRNA maturation steps and is essential for U snRNA nuclear export in multicellular eukaryotes. The 2A crystal structure of human CBC shows that the large subunit, CBP80, comprises three domains, each containing consecutive helical hairpins and resembling the so-called MIF4G domain found in several other proteins involved in RNA metabolism. The small subunit, CPB20, has an RNP fold and associates with the second and third domains of CBP80. Site-directed mutagenesis revealed 4 residues of CBP20 which are critical for cap binding. A model for cap binding is proposed based on these results and the known mode of binding of RNA to RNP domains.

Amino Acid Sequence↗
PubMed2001

Obesity prevalence and trends in Latin-American countries.

The prevalence of obesity in some lower-income and transitional countries is as high as, or even higher than, the prevalence reported in developed nations, and it seems to be increasing rapidly. In most countries, the prevalence of obesity is higher in women than in men, and higher in urban than in rural areas. Preobesity prevalence is very high in most Latin-American countries. Sixty per cent of the population in Venado Tuerto (Argentina) has a body mass index (BMI) of > or = 25 kg m-2, as do 35% of the population in Brazil, 60% in Mexico, 68% in Paraguay and 53% in Peru. Trends are available from Brazil, where marked increases in the prevalence of obesity have occurred, except in women from higher-income groups. Women from the higher-income quartiles in urban regions experienced a marked reduction in obesity prevalence from 1989 to 1997 (12.8 to 9.2%). Although data in children is scant, the prevalence of undernutrition is decreasing and the prevalence of obesity is high also in Latin-American children. The prevalence of obesity is high even in minority Indian groups. Rapid changes in dietary structure (in particular associated with urbanization) and major changes in the levels of physical activity, both occupationally and during leisure time, may explain these changes.

Child↗
PubMed2001

Defecographic measurements of rectal intussusception and prolapse in patients and in asymptomatic subjects.

OBJECTIVE: The aim of this study was to provide measurements for the defecographic diagnosis of rectal intussusception and rectal prolapse. MATERIALS AND METHODS: Four hundred thirty-seven consecutive patients with defecation and micturition disorders and gynecologic complaints were studied by means of defecography (120 patients), colpodefecography (17 patients), or cystocolpodefecography (300 patients). As a control group, 43 asymptomatic subjects underwent defecographic examination. RESULTS: Thirty-five patients were found to have rectal intussusception and 18, to have rectal prolapse. Anterior and posterior rectal wall folding thickness, intussuscipiens diameter, intussusceptum lumen diameter, and the ratio between the intussuscipiens diameter and the intussusceptum lumen diameter were measured in all patients. The findings were compared with those obtained in 13 of 43 asymptomatic subjects with rectal outline changes mimicking intussusception. Rectal folding thickness and the ratio between the intussuscipiens diameter and the intussusceptum lumen diameter were significantly greater in subjects with rectal intussusception and rectal prolapse than in asymptomatic subjects with rectal mucosa folding. CONCLUSION: Our findings suggest that dynamic evacuation radiology contributes to making a differential diagnosis between rectal intussusception and mucosal folds in the rectum.

Case-Control Studies↗
PubMed2000

Combined immunodeficiencies due to defects in signal transduction: defects of the gammac-JAK3 signaling pathway as a model.

Combined immune deficiencies comprise a spectrum of genetic disorders characterized by developmental or functional defects of both T and B lymphocytes. Recent progress in cell biology and molecular genetics has unraveled the pathophysiology of most of these defects. In particular, the most common form of severe combined immune deficiency in humans, with lack of circulating T cells, a normal or increased number of B lymphocytes, and an X-linked pattern of inheritance (SCIDXI) has been shown to be due to defects of the IL2RG gene, encoding for the common gamma chain (gammac), shared by several cytokine receptors. Furthermore, defects of the JAK3 gene, encoding for an intracellular tyrosine kinase required for signal transduction through gammac-containing cytokine receptors, have been identified in patients with autosomal recessive T-B+ SCID. Characterization of the functional properties of cytokines that signal through the gammac-JAK3 signaling pathway has been favored by the detailed analysis of SCID patients. Specifically, the key role of IL-7 in promoting T cell development has been substantiated by the identification of rare patients with T-B+ SCID who have a defect in the alpha subunit of the IL-7 receptor (IL7Ralpha). The heterogeneity of genetic defects along the same signaling pathway that may lead to combined immune deficiency is paralleled by the heterogeneity of immunological phenotypes that may associate with defects in the same gene, thus creating a need for detailed immunological and molecular investigations in order to dissect the spectrum of combined immune deficiencies in humans.

Animals↗
PubMed2000

Of genes and phenotypes: the immunological and molecular spectrum of combined immune deficiency. Defects of the gamma(c)-JAK3 signaling pathway as a model.

Cytokines play a major role in lymphoid development. Defects of the common gamma chain (gamma(c)) or of the JAK3 protein in humans have been shown to result in a severe combined immune deficiency (SCID), with a profound defect in T and natural killer (NK)-cell development, whereas B-cell generation is apparently unaffected (T-B+NK-SCID). While extensive molecular and biochemical analysis of these patients has been instrumental in understanding better the biological properties of the gamma(c) and JAK3 protein, an unexpected phenotypic heterogeneity of gamma(c) and JAK3 deficiency has emerged, indicating the need for appropriate and extensive investigations even in patients with atypical presentations. At the same time, characterization of the defects has been instrumental in the development of novel therapeutic approaches, from in utero hematopoietic stem cell transplantation to gene therapy.

Cytokines↗
PubMed1999

Influence of maternal CD4 levels on the predictive value of virus load over mother-to-child transmission of human immunodeficiency virus type 1 (HIV-1). Study Group for Vertical Transmission.

Forty-four anti-HIV seropositive pregnant women were enrolled in a study of maternal factors related to mother-to-infant human immunodeficiency virus type 1 (HIV-1) transmission. HIV-1 infection was documented in 11 of 45 infants (24.4%). Obstetric factors, maternal CD4 counts, and disease stage were not related to the risk of transmission. HIV-1 RNA levels at delivery were significantly higher in mothers who transmitted the infection (P = .024). A strong relationship between viral load and risk of transmission was observed in women with stage A1 (P= .006), but not in those with stages A2-A3. These results suggest that vertical transmission of HIV-1 is multifactorial and that viral load plays a major role in mothers with early-stage HIV-1 infection.

Adult↗
PubMed1999

Brain tumors in children under 3 years of age. Recent experience (1987-1997) in 39 patients.

Brain tumors in children under 3 years of age differ in clinical presentation and pathological behavior from those in older patients. In this study, we reviewed data from 39 children (24 males and 15 females) under 3 years of age who were treated for intracranial brain tumors since the introduction of magnetic resonance imaging. The purpose was to assess correlations between clinicoradiological and treatment-related factors, and their impact on prognosis. The following factors were analyzed: sex, age, duration of symptoms, intracranial hypertension on admission, tumor location, surgical removal and histology. Associations between these factors and correlations with prognosis were determined using bivariate analyses (chi(2) test) and Kaplan-Meier survival curves. Collins' concept of a period of risk recurrence was tested. Mean follow-up was 41 months (range 0-136). In March 1998, 20 children were still alive (51.2%) with a mean survival time of 65 months (range 2-136). The incidence of supratentorial tumors was significantly higher in children less than 1 year old (p = 0.027). Lateral tumors were 9/10 (90%) supratentorial versus only 7/26 (27%) midline tumors (p = 0.001). Outcome (dead or alive) was significantly better (p = 0.037) for low-grade astrocytomas (9/12 = 75% survival) when compared to ependymomas (2/6 = 33%) and primitive neuroectodermal tumors (3/12 = 25%). Total tumor removal was achieved in 20 cases and was associated with a better outcome (65 vs. 33% survival; p = 0.049). Survival analysis confirmed a worse prognosis for children with ependymomas and primitive neuroectodermal tumors (p = 0.011) and revealed a worse survival for children with intracranial hypertension on admission (p = 0.047). Total tumor removal was associated with a longer survival, although not significantly (p = 0. 077). Finally, we found no exceptions to Collins' law.

Brain Neoplasms↗
PubMed1998

Unusual charge stabilization of NADP+ in 17beta-hydroxysteroid dehydrogenase.

Type 1 17beta-hydroxysteroid dehydrogenase (17beta-HSD1), a member of the short chain dehydrogenase reductase (SDR) family, is responsible for the synthesis of 17beta-estradiol, the biologically active estrogen involved in the genesis and development of human breast cancers. Here, we report the crystal structures of the H221L 17beta-HSD1 mutant complexed to NADP+ and estradiol and the H221L mutant/NAD+ and a H221Q mutant/estradiol complexes. These structures provide a complete picture of the NADP+-enzyme interactions involving the flexible 191-199 loop (well ordered in the H221L mutant) and suggest that the hydrophobic residues Phe192-Met193 could facilitate hydride transfer. 17beta-HSD1 appears to be unique among the members of the SDR protein family in that one of the two basic residues involved in the charge compensation of the 2'-phosphate does not belong to the Rossmann-fold motif. The remarkable stabilization of the NADP+ 2'-phosphate by the enzyme also clearly establishes its preference for this cofactor relative to NAD+. Analysis of the catalytic properties of, and estradiol binding to, the two mutants suggests that the His221-steroid O3 hydrogen bond plays an important role in substrate specificity.

17-Hydroxysteroid Dehydrogenases↗
PubMed1998

Successful reconstruction of refractory posttraumatic skull base defects with free radial forearm flap.

After our experience with two patients who had persistent posttraumatic defects of the anterior skull base, we recommend using a deepithelialized free radial forearm flap for one-stage reconstruction. The flap provides a thin, water-tight barrier between the cranial cavity and the subcranial spaces for effective prevention of cerebrospinal fluid leakage and ascending infection. It is particularly useful when local flap options are not available.

Adult↗
PubMed1998

Prognostic factors in childhood intracranial ependymomas: the role of age and tumor location.

Despite several clinical reports on intracranial ependymomas in children, the factors which affect prognosis, and the possibility that certain combinations of factors might limit survival, are still a matter of debate. Between 1976 and 1996 we operated on 35 children with intracranial ependymomas. Postoperative irradiation was given to 27 patients, with associated chemotherapy in 6 cases. Mean follow-up was 62 months. In 12 patients a 5-year follow-up was possible. In October 1996, 18 patients (51.4%) were still alive, the longest disease-free follow-up being 20 years, and the shortest 8 months. We analyzed the prognostic relevance of eight factors. For each factor, different subgroups were distinguished and compared as follows: age at diagnosis (<4 vs. >/=4 years), sex, tumor location (supratentorial vs. infratentorial), tumor size (<4 vs. 4-7 vs. >7 cm), surgical removal (total vs. subtotal), histology (low-grade vs. anaplastic), morphology (solid vs. cystic), adjuvant therapies (treatment vs. no treatment). Two-way contingency tables were made to identify associations between variables. The only significant association was between age and tumor location (p = 0.022): in children under 4, tumors were almost invariably located in the posterior fossa (9 out of 10 cases) with a clear preference for the lateral recess (8 cases). Other correlations were not significant. Kaplan-Meier survival curves were compared to assess the prognostic relevance of each factor. Survival was significantly lower for children under 4, for those with posterior fossa tumors, and for patients with residual tumor (p < 0.05). A multivariate analysis compared variables which significantly affected survival, revealing that age is the most important factor affecting prognosis (p < 0.05), while tumor location and surgical removal do not add any significance to the effect of age on survival. We conclude that age has the strongest prognostic relevance in childhood intracranial ependymomas, while the effect of tumor location on survival may be related to the high incidence of lateral recess ependymomas in younger children.

Age Distribution↗
PubMed1998

Prospective study of mother-to-infant transmission of hepatitis C virus (HCV) infection. Study Group for Vertical Transmission.

Seventy-five women with anti-hepatitis C virus (HCV) antibody were enrolled prospectively during pregnancy or at delivery for study of mother-to-child transmission of HCV. Twenty-three women were coinfected with the human immunodeficiency virus (HIV). Seventy babies were monitored for at least 6 months. HCV infection was diagnosed in six infants (8.6%), four of whom were born to anti-HIV-positive mothers. HCV RNA was first detected between 2 and 6 months, and the genotypes of infected babies matched those of their mothers (type 1: n = 4; type 3: n = 2). Identical master sequences of the hypervariable region (HVR1) were detected in a mother-infant pair. In three babies coinfected with HCV and HIV, anti-HCV disappeared between 2 and 7 months, being persistently negative in two cases monitored for 11 and 26 months. Transmitting mothers did not differ significantly from those who did not transmit the infection with anti-HIV, HCV genotypes, and viral load at delivery, but had lower rate of reactivity to C100 by the recombinant immunoblot assay (RIBA) (P < .01). This prospective study confirms transmission of HCV from anti-HIV-negative mothers (4.4% in this series). Absence of anti-C100 antibodies at delivery is apparently related to increased risk of vertical transmission. Seronegative HCV infection can be observed in children coinfected with HIV.

Adult↗
PubMed1998

[Deglutition in patients treated with reconstructive laryngectomy].

INTRODUCTION: We stress the importance of dynamic radiologic studies of swallowing in the patients submitted to reconstructive laryngectomy. MATERIAL AND METHODS: January, 1989, to December, 1996, we examined 36 patients submitted to reconstructive laryngectomy, namely cricohyoidoepiglottopexy in 34 cases, cricohyoidopexy in 1 case and Guerrier's cricohyoidoepiglottopexy in 1 case. Dynamic radiologic studies were performed with fluoroscopic videorecording (Sony U-Matic RM 580) from an X-ray unit. The study was performed with the patients standing or sitting, initially acquiring AP and LL fluoroscopic images of the oropharyngeal region at rest and during swallowing. The patients then swallowed 2 boluses of 5 ml liquid (60%) and semiliquid (250%) barium. When aspiration was suspected, we began with a 2-ml bolus. RESULTS: The patients were grouped by symptoms: group A patients had no symptoms, group B patients had dysphagia and group C patients presented aspiration. The functional changes were: reduced pharyngeal contraction, reduced epiglottis deflection, reduced hyoid bone elevation, aspiration, altered upper esophageal sphincter function. The organic alterations were: parapharyngeal diverticulum, pharyngeal stenosis, posterior pharyngeal wall introflexion. Three group A patients had severe posterior pharyngeal wall introflexion, 4 had marked retention and 2 of them presented postswallowing aspiration. Two group B patients had major retention, 1 cricopharyngeal incoordination, 3 posterior pharyngeal wall introflexion, 2 a pseudodiverticulum and 2 a luminal stenosis. Seven group C patients had intraswallowing and 3 postswallowing aspiration. CONCLUSION: The videofluorographic identification of organic and functional complications, sometimes unknown in asymptomatic patients, is useful for therapy and suggests the speech specialist the best compensatory mechanism to improve the patients' swallowing and consequently their quality of life. Moreover, videofluorography of swallowing is a very useful tool in the follow-up, to monitor treatment outcome after rehabilitation.

Deglutition↗
PubMed1997

Analyses of prognostic factors in a retrospective review of 92 children with ependymoma: Italian Pediatric Neuro-oncology Group.

The principal aim of this report is to present the results of multivariate analyses conducted to identify clinical prognostic factors in 92 children aged < 16 years with ependymoma (EPD) retrospectively collected in seven Italian centres. They were treated over a 16-year period (1977-1993). Treatment modalities varied. Surgery and radiotherapy (RT) was the "gold standard" management method for the majority of these children. Only in the late 1980s did some of them receive chemotherapy (CT), mainly with vincristine, lomustine (CCNU) and prednisone. The median follow-up of the entire study population is 36 months (average 43 months; range 12 to 214 months). The 10-year overall (OS) and the progression-free survival (PFS) of the study population were 55.5% (CI 41.4-69.4%) and 34.7% (CI 21.4-47.8%), respectively. Age (< 5 years; > 5 years), sex, site (infratentorial vs. supratentorial), histology (anaplastic/malignant vs. non-anaplastic/non-malignant), type of resection (complete vs. incomplete); use and fields of RT, and of CT employed were entered in a multivariate regression model to test their impact on OS and PFS. On univariate analysis, radical surgery, the use of RT and age more than 5 years at the time of diagnosis achieved statistically significant values for predicting long-term OS and PFS. Histology reached marginal statistical significance but only for PFS. When those variables were entered in a multivariate analysis only radical resection (P = 0.00142 and 0.0001) resulted a significant factor for predicting long-term OS and PFS, while the use of RT reached a marginal statistical significance, but only for PFS (P = 0.05). Children who had the tumour completely resected did significantly better than all the others who had less than a complete resection, with a 10-year OS and PFS for the two groups of patients of 69.8% (CI 53-86.5%) and 57.2% (CI 40.3-75%) and of 32.5% (CI 8.5-57.6%) and 11.1% (0-24.4%), respectively. These findings suggest that, for childhood EPD, radical resection should be pursued as much as reasonably possible. Thus, it seems justified proposing for future trials, patient stratification by entity of surgical resection.

Adolescent↗