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M Catalano

Publications and source records attributed to M Catalano.

At least 19 recordsLinked to original sources
PubMed2005

Functional analysis of R75Q mutation in the gene coding for Connexin 26 identified in a family with nonsyndromic hearing loss.

Mutations in the gene (GJB2) coding for Connexin 26 (Cx26) are responsible for genetic forms of sensorineural hearing loss. This article describes a family characterized by congenital profound hearing loss, inherited in an autosomal dominant fashion and associated to a R75Q substitution in Cx26. Cell transfection and fluorescence imaging, dye transfer experiments and dual patch clamp recording showed that the mutant completely prevents the formation of functional channels despite assembling into junctional plaques, in communication incompetent HeLa cells. The disease is not associated with palmar and plantar keratosis in any of the family members, suggesting that R75Q substitution is not sufficient for the development of the complete syndromic phenotype. The association of palmar and plantar keratosis with profound hearing loss may be dependent on genetic background, requiring a functional interaction between the mutated Cx26 and other epidermally expressed connexins.

Connexin 26↗
PubMed2004

Genetic characterisation of Helicobacter pylori isolates from an Argentinean adult population based on cag pathogenicity island right-end motifs, lspA-glmM polymorphism and iceA and vacA genotypes.

Isolates of Helicobacter pylori from 88 patients were characterised by cagA status, cagA pathogenicity island (PAI) right-end motifs, iceA, vacA and lspA-glmM genotypes, primarily by PCR-based analysis, to investigate whether Argentinean isolates differed from those recovered in southern Europe or other Latin American countries. PCR-based analysis of vacA alleles was confirmed by reverse hybridisation in 56 cases, while sequence analysis was performed either when iceA and vacA genotypes could not be determined by PCR, or to investigate PCR and reverse hybridisation vacA genotyping discordance. Typing by lspA-glmM restriction fragment length polymorphism was performed with HhaI and AluI. The pattern of cag PAI right-end motifs and the prevalence of type Ia were similar to those in isolates from southern European countries, with cagA(+)/iceA1/vacA-s1 m1 being the commonest genotype. Reverse hybridisation identified a vacA-s1a/s1b recombinant allele, confirmed by sequencing analysis. Analysis of lspA-glmM genotypes identified at least 73 unrelated strains. Few mixed infections were identified, but in one case, isolates from a single biopsy exhibiting two vacA alleles were shown by lspA-glmM fingerprints to be two unrelated strains. No associated effect on ulcer disease risk was demonstrated by analysis of cagA, vacA and iceA status. Overall, the isolates of H. pylori from Argentina were similar to isolates from southern Europe or Latin American countries, and infections were associated mainly with single H. pylori strains.

Adult↗
PubMed2004

Multidimensional Voice Program (MDVP) and amplitude variation parameters in euphonic adult subjects. Normative study.

The introduction, in the late 70s, of the first digital spectrograph (DSP Sonograph) by Kay Elemetrics has improved the possibilities of spectroacoustic voice analysis in the clinical field. Thanks to the marketing, in 1993, of the Multi Dimensional Voice Program (MDVP) advanced system, it is now possible to analyse 33 quantitative voice parameters which, in turn, allow evaluation of fundamental frequency, amplitude and spectral energy balance and the presence of any sonority gap and diplophony. Despite its potentials, the above-mentioned system is not widely used yet, partly on account of the lack of a standard procedure. Indeed, there are still only a few case reports in the literature taking into consideration prescriptive aspects related both to procedure and analysis. This study aims to provide the results of amplitude perturbation parameter analysis in euphonic adult patients. In our opinion, these are the most significant parameters in determining the severity of a phonation disorder. The study has been carried out on 35 patients (24 female, 11 male, mean age 31.6 years, range 19-59). The voice signal has been recorded using a 4300 B Kay Computer Speech Lab (CSL) supported by a personal computer including a SM48 Shure-Prolog microphone located at a distance of 15 cm and angled at 45 degrees. Input microphone saturation has been adjusted to 6/9 of the CH1 channel. The voice sample consisted in a held /a/ and the analysis has been carried out on the central 3 seconds of the recording. The analysis has been carried out using a 5105 MDVP software version 2.3 and the signal digitalised at a 50 kHz sample rate. In order for the sample to be as free from intensity or frequency changes as possible, each patient underwent a training session (including at least 3 phonation tests) before the recording. The study included only emissions between 55 and 65 dB and with spectrum stability. Environmental noise has constantly been monitored and maintained below 30 dB. Data from the 24 female patients showed: absolute Shimmer (ShdB) = 0.203 dB, relative shimmer (Shim %) = 2.226, amplitude perturbation quotient (APQ) = 1.758, smoothed amplitude perturbation quotient = 3.309, peak amplitude variation (vAm) = 7.042. Data from the 11 males showed: absolute Shimmer (ShdB) = 0.269 dB, relative shimmer (Shim %) = 2.892, amplitude perturbation quotient (APQ) = 2.611, smoothed amplitude perturbation quotient (SAPQ) = 3.433, peak amplitude variation (vAm) = 6.385. Statistical analysis (t test) showed no statistically significant difference between sexes, thus a single set of rules was used for both sexes.

Adult↗
PubMed2003

Anticarcinogenic Bowman Birk inhibitor isolated from snail medic seeds (Medicago scutellata): solution structure and analysis of self-association behavior.

The high-resolution three-dimensional structure of a Bowman Birk inhibitor, purified from snail medic seeds (Medicago scutellata) (MSTI), has been determined in solution by 1H NMR spectroscopy at pH 5.6 and 27 degrees C. The structure of MSTI comprises two distinct symmetric domains each composed of a three-stranded beta-sheet containing a VIb type loop, where the active sites are located. A characteristic geometry of three aromatic residues confers stability to this protein, and we observe that this feature is conserved in all the Bowman Birk inhibitors of known structure. The two active domains exhibit different conformational features: the second domain displays higher flexibility and hydrophobicity with respect to the first one, and these properties have been correlated to a lower trypsin inhibitory specificity, in agreement with titration studies that have shown a stoichiometric ratio MSTI:trypsin of 1:1.5. NMR analysis indicated that MSTI undergoes self-association at concentrations higher than 2 mM, and the residues involved in this mechanism are localized at opposite faces of the molecule, having the highest positive and negative potential, respectively, thus indicating that electrostatic intermolecular interactions are the driving forces for MSTI association. Most of the residues affected by self-association are highly conserved in BBIs from different seeds, suggesting a functional relevance for these charged superficial patches, possibly involved in the interaction with other enzymes or macromolecules, thus triggering anti-carcinogenic activity.

Amides↗
PubMed2003

Human nuclear transcription factor gene CREM: genomic organization, mutation screening, and association analysis in panic disorder.

Panic disorder is an anxiety disorder with an estimated heritability of 48%. Variation in the gene of the nuclear transcription factor "cAMP-responsive element modulator" (CREM) might contribute to its pathogenesis. CREM knock-out mice exhibit significantly less anxiety behavior than wild-type mice and the alternative CREM gene product "inducible cAMP early repressor" (ICER) plays a pivotal role in the hypothalamo-pituitary-adrenal (HPA) axis, which is disturbed in panic disorder. We characterized the genomic organization of the human CREM gene and performed a systematic mutation screening by means of single stranded conformational analysis (SSCA) in a sample of 40 German patients with panic disorder (DSM-III-R). Four novel single nucleotide polymorphisms in CREM promoters P 1 and P 4, one trinucleotide (ATT)-repeat polymorphism in CREM promoter P 2-generating the ICER isoform-and a rare amino acid substitution in CREM exon glut 2 were identified. Association analysis in an extended sample of German patients (n = 88) revealed a significant excess of the shorter CREM P 2 promoter eight-repeat trinucleotide allele and of genotypes containing the eight-repeat trinucleotide allele in panic disorder (P = 0.02), in particular in panic disorder without agoraphobia (P = 0.001). A replication study in independent Italian (n = 76) and Spanish (n = 62) samples, however, failed to confirm this observation. This suggests that the CREM P 2 promoter trinucleotide polymorphism is not a major susceptibility factor in the pathogenesis of panic disorder. Functional analysis of the observed CREM P 2 promoter polymorphism as well as studies in independent panic disorder samples are necessary.

Agoraphobia↗
PubMed2003

Mitochondrial disruption and apoptosis in lymphocytes of an HIV infected patient affected by lactic acidosis after treatment with highly active antiretroviral therapy.

AIMS: Highly active antiretroviral therapy (HAART) can induce an increase in lactic acid concentrations that seems to be caused by mitochondrial dysfunction induced by the interaction of nucleoside reverse transcriptase inhibitors (NRTIs) with DNA polymerase gamma in the mitochondria. Mitochondrial alterations have been described in liver and muscle cells of NRTI treated human immunodeficiency virus (HIV) infected patients. Because lymphocytes are the main target for HIV and because mitochondria are involved in apoptosis, we studied mitochondrial morphology and apoptosis in the lymphocytes of an HIV infected patient with severe lactic acidosis after treatment with stavudine, didanosine, and indinavir. METHODS: The patient was a 39 year old woman. After two years of treatment she developed rapid weight loss with severe fat wasting, peripheral neuropathy, and hyperlacticaemia, which persisted after treatment withdrawal. The numbers and the morphology of the mitochondria were evaluated by electronic microscopy; the percentage of apoptotic cells was calculated by flow cytometry after staining with annexine V and by fluorescent microscopy after staining with ethidium bromide and acridine orange. RESULTS: The numbers of mitochondria in the lymphocytes were greatly decreased when compared with the lymphocytes of healthy individuals. The most important mitochondrial morphological alterations were swelling and the disruption of cristae and internal mitochondrial structure. These alterations were more evident during the period in which lactic acid values were very high. Moreover, a high percentage of apoptotic lymphocytes was seen. Morphological examination conducted one week after the normalisation of lacticaemia showed a pronounced increase in the number of mitochondria. The morphological alterations were no longer evident, although the size of each mitochondrion was smaller than normal. Moreover, the percentage of apoptotic cells was lower than 5%. CONCLUSIONS: This report describes important morphological alterations in lymphocyte mitochondria in an HIV infected patient during a severe phase of HAART induced hyperlacticaemia. These alterations persisted for several weeks after treatment withdrawal and were associated with an increase in lymphocyte apoptosis. Considering the important role of mitochondria in the apoptotic pathway, the increase in lymphocyte apoptosis may be a consequence of proapoptotic factors released from altered mitochondria.

Acidosis, Lactic↗
PubMed2003

Development of communication and speech skills after cochlear implant in a sign language child.

In selecting patients to undergo cochlear implant, a pre-existing use of sign language gives rise to two problems that have been widely debated in the literature. First, the caution shown toward the candidacy of patients using this mode of communication, since it is considered a possible element of interference in the acquisition of speech. Secondly, refusal of the cochlear implant procedure, on the part of the deaf community, on the grounds both of cultural identity and of it being more "natural" for a deaf person to use an unimpaired visual channel rather than an impaired hearing channel. In order to establish whether knowledge of sign language does, indeed, affect speech production negatively and evaluate which mode of communication, oral or gestual, is preferred, the present investigation was carried out on a preverbal deaf child who had undergone cochlear implant at about 7 years of age and has always used both languages. His verbal skills were evaluated in the precochlear implant stage, then at 6 and 12 months after, together with the changes in his use of sign language and in the relationship between the two modes. Results, besides observing the presence of linguistic evolution at each level examined and already evident at 6 months, also documented a progressive reduction in the spontaneous use of sign language. In conclusion, the present experience revealed no temporal or qualitative differences in post-cochlear implant evolution of speech skills, in comparison with that observed in patients with an exclusively aural-oral approach. Furthermore, the increased use of the hearing pathway, made possible by cochlear implant, determined a spontaneous choice of verbal language as the most natural and economic mode of communication.

Child↗
PubMed2003

Changes in clinical and instrumental vestibular parameters following acute exposition to auditory stress.

Besides Tullio's phenomenon, resulting from anatomic changes in the labyrinth, a hypersensitivity to acoustic stimuli of the saccular structures appears to be the underlying cause of the vestibular responses detected in some patients. In order to evaluate the incidence of vestibular symptoms triggered by acute exposure to auditory stress (disco music), 40 subjects aged between 18 and 26 years, with no audiological and vestibular disorders, were submitted to otoneurologic tests. Subjects were exposed to disco music [intensity 128 dB (C)], for 3 hours. Tests have been carried out before and immediately after exposure. Canalar and macular functions have been evaluated using vestibular investigation techniques and vestibular evoked myogenic potentials. When compared to baseline data, post-exposure test results did not reveal any canalar damage. Pre- and post-exposure recordings of the vestibular-oculomotor reflex threshold have shown no significant changes. Conversely, post-stimulus recordings have shown a significant increase in the amplitude of the vestibular evoked myogenic potential response, thus indicating a possible irritative involvement of the macular receptor. This result suggests a direct action upon the receptor by acoustic stimulation which could, therefore, be the underlying cause of vestibular symptoms reported by patients following exposure to sufficiently intense acoustic stimuli. Prior to this study. a questionnaire concerning the relationship between habitual disco visiting and audio-vestibular symptoms has been completed by 310 students at the University of Catanzaro. This survey revealed a significant incidence of vestibular symptoms due to acoustic stress (Tullio's phenomenon) which led us to hypothesise that balance disorders due to auditory stress are much more frequent than commonly held, particularly since, in many cases, diagnoses is unknown or not easy due to the difficult procedures by which these conditions are diagnosed.

Acoustic Stimulation↗
PubMed2002

High levels of exogenous C2-ceramide promote morphological and biochemical evidences of necrotic features in thyroid follicular cells.

CD95 and ceramide are known to be involved in the apoptotic mechanism. The triggering of CD95 induces a cascade of metabolic events that progressively and dramatically modifies the cell shape by intense membrane blebbing, leading to apoptotic bodies production. Although the CD95 pathway has been abundantly described in normal thyrocytes, the effects of cell permeable synthetic ceramide at morphological and biochemical levels are not fully known. In the present study, we show that thyroid follicular cells (TFC) exposed to 20 microM of C(2)-ceramide for 4 h are characterized by morphological features of necrosis, such as electron-lucent cytoplasm, mitochondrial swelling, and loss of plasma membrane integrity without drastic morphological changes in the nuclei. By contrast, TFC treated with 2 microM of C(2)-ceramide for 4 h are able to accumulate GD3, activate caspases cascade, and induce apoptosis. Furthermore, we provide evidence that 20 microM of C(2)-ceramide determine the destruction of mitochondria and are not able to induce PARP cleavage and internucleosomal DNA fragmentation, suggesting that the apoptotic program is not activated during the death process and nuclear DNA is randomly cleaved as the consequence of cellular degeneration. Pretreatment with 30 microM of zVAD-fmk rescued TFC from 2 microM of C(2)-ceramide-induced apoptosis, whereas, 20 microM of C(2)-ceramide exposure induced necrotic features. Deltapsi(m) was obviously altered in cells treated with 20 microM of C(2)-ceramide for 4 h (75% +/- 3.5%) compared with the low percentage (12.5% +/- 0.4%) of cells with altered Deltapsi(m) exposed to 2 microM of C(2)-ceramide. Whereas, only 20% +/- 1.1% of cells treated with anti-CD95 for 1 h showed altered Deltapsi(m). Additionally, Bax and Bak, two pro-apoptotic members, seem to be not oligomerized in the mitochondrial membrane following ceramide exposure. These results imply that high levels of exogenous ceramide contribute to the necrotic process in TFC, and may provide key molecular basis to the understanding of thyroid signaling pathways that might promote the apoptotic mechanism in thyroid tumoral cells.

Apoptosis↗
PubMed2001

Efficacy of two DNA fingerprinting methods for typing Acinetobacter baumannii isolates.

Performance of macrorestriction and repetitive extragenic palindromic DNA sequence-based PCR (REP-PCR) to type Acinetobacter baumannii isolates was quantitatively estimated using a test population of 54 outbreak-related, 29 endemic infection-related and 17 epidemiologically-unrelated isolates. Reproducibility and stability for macrorestriction were 100%, and REP-PCR showed only slightly lower stability. Macrorestriction resolved 18 fingerprints and REP-PCR 10 DNA patterns, forming eight and seven clusters at 75% of similarity level, respectively. Intercluster band variation was > 7 bands for both methods. Although, all endemic isolates, except one, were concordantly grouped by both methods, macrorestriction distinguished a greater number of subtypes over one year study. For outbreaks, the epidemiologic concordance for both methods was 88%. The discriminatory index for macrorestriction and REP-PCR was 0.884 and 0.877, respectively. In conclusion, both methods showed similar efficacy as epidemiological markers, and by concordance, this study demonstrated that for REP-PCR typing, a > or = 7 bands difference seemed an appropriate threshold to identify unrelated strains.

Acinetobacter↗
PubMed2001

Helicobacter pylori vacA genotypes, cagA status and ureA-B polymorphism in isolates recovered from an Argentine population.

Several reports have evidenced geographic differences in the prevalence of vacA (vacuolating cytotoxin gene) alleles and cagA (cytotoxin-associated gene) status among Helicobacter pylori isolates. We investigated the occurrence of these virulence-associated genes status among our isolates, and their relationship with ulcer disease outcome. Besides, ureA-B polymorphism was studied. One hundred isolates, comprising 32 from patients with ulcer disease (UD) and 68 from patients with non-ulcer dyspepsia (NUD), were analyzed. Eighty-four percent of isolates were cagA-positive without statistically significant difference in prevalence between patients with UD or NUD. Genotype vacA-s1m1 was predominant, although unlike other South American regions, subtype s1am1 occurrence was higher than s1b. The multivariate model used to estimate the predictive value of cagA and vacA status for UD development disclosed infection with vacA-s1am1 isolates as the only variable that increased the risk of UD onset. ureAB fingerprinting showed considerable genetic divergence among isolates, however, confirmed that certain DNA banding profiles are conserved worldwide.

Adult↗
PubMed2001

Functionally gene-linked polymorphic regions and genetically controlled neurotransmitters metabolism.

In clinical psychopharmacology, the existence of marked inter-individual differences in both outcome and side effects is a common observation. Consequently, pharmacogenetics has also gained an increasing interest in psychiatry. Recent exciting findings seem to suggest that the growing interest in regulatory regions of candidate genes and neurotransmitters metabolism, together with the application of sophisticated molecular approaches, may offer new opportunities in neuropsychopharmacology. Indeed, quantitative variation of gene expression and/or of neurotransmitters metabolism could better explain both psychopathology and clinical response to psychotropic drugs. Three functional polymorphisms, and their possible relationship with clinical variables, are discussed. The first is the 44-bp insertion/deletion reported in the promoter region of the serotonin transporter gene. A functional repeat polymorphism in the promoter region of the gene encoding for the enzyme monoamine oxidase A represents the second example. The last is a functional polymorphism within the coding region of the gene encoding for the enzyme catechol-O-methyltransferase

Animals↗
PubMed2001

Genotypic analysis of Staphylococcus aureus from milk of dairy cows with mastitis in Argentina.

Staphylococcus aureus is the most prevalent pathogen causing mastitis of dairy ruminants. This study was developed to ascertain the genotypes and genealogical relationship among strains isolated from milk of bovines with mastitis in Argentina. Molecular epidemiological analysis of S. aureus was performed on 112 isolates from 21 districts. Clonality was assessed by SmaI pulsed-field gel electrophoresis (PFGE) typing, automated EcoRI ribotyping and restriction enzyme analysis of plasmid (REAP) DNA profiles. A total of 22 band patterns distributed in four clusters were found by SmaI PFGE analysis. The similarity of clusters 2, 3 and 4 with cluster 1 was 0.73, 0.69 and 0.33, respectively, and 101 of 112 isolates belonged in cluster 1. PFGE band patterns from 42 isolates within cluster I were indistinguishable from each other (type A). The second largest group of isolates with indistinguishable PFGE band patterns was subtype A11, which was composed of 19 isolates. Automated ribotyping assigned the 112 isolates into 13 ribotypes. Among these, the most prevalent ribotypes I and VI were composed of 49 and 35 isolates respectively. Although there was certain correspondence between PFGE genotypes and ribotypes, further discrimination was achieved by combining both methods. REAP DNA profile analysis was useful to provide even further discrimination between isolates with identical PFGE genotype and ribotype. The most prevalent S. aureus strains A/I and A11/VI were widely distributed in the country and were not restricted to individual nearby locations. Prevalence of these two strains varied consecutively within a period of 8 years. Whether the shift in type prevalence was due to selection of a phenotypic trait remains undisclosed.

Animals↗
PubMed2001

Interobserver agreement for EUS in the evaluation and diagnosis of submucosal masses.

INTRODUCTION: EUS is an accurate means of evaluating and diagnosing submucosal lesions of the GI tract. The aim of this study was to prospectively determine interobserver agreement for the EUS classification of submucosal masses among endosonographers with different levels of training and experience from multiple centers. METHODS: Twenty patients with submucosal mass lesions diagnosed by upper endoscopy underwent EUS. Surgical findings were available for 16 patients. In 4 patients with obvious cystic/vascular structures (i.e., varices) no surgical specimen was necessary. A blinded observer developed a study videotape of critical endoscopic and EUS real-time imaging for each lesion. The videotape was distributed to 10 endosonographers, each with at least 1 year of experience, who independently reviewed the videotape and recorded their diagnosis based on EUS features. These endosonographers used previously agreed-upon standardized EUS diagnostic criteria for each category of lesion. A kappa (kappa) statistic, used to evaluate agreement, was calculated for each lesion category for the 10 endosonographers as a group and individually. An overall kappa statistic was also calculated. Significance was analyzed with a two-tailed t test. RESULTS: Agreement was excellent for cystic lesions (kappa = 0.80) and extrinsic compressions (kappa = 0.94), good for lipoma (kappa = 0.65), fair for leiomyoma and vascular lesions (kappa = 0.53 and 0.54, respectively), and poor for other submucosal lesions (kappa = 0.34). Overall agreement among observers was good (kappa = 0.63). Furthermore, a significant association was noted between total years of EUS experience and the number of correct answers (p = 0.01). CONCLUSIONS: Interobserver agreement is good for characterizing submucosal masses by EUS. However, it appears to be better for some lesions than others. The overall length of experience with EUS appears to play an important role in the accuracy of this modality in the evaluation of submucosal lesions.

Endosonography↗
PubMed2001

The hypothalamic magnocellular neurosecretory system in developing rats.

Studies concerning the development of the magnocellular system are scarce and discordant in literature. We carried out an immunohistochemical study on supraotic and paraventricular hypothalamic nuclei using antivasopressin and antioxytocin antibodies in developing rats between the 15th day of intrauterine life and the 6th day of postnatal life. In addition, we performed RT-PCR experiments to establish the stage at which these hormones appear and neurosecretory activity commences. The results showed that supraoptic and paraventricular nuclei appear, respectively, on the 16th and the 18th day of intrauterine life and both immediately synthetize vasopressin neurohormone. By contrast, synthesis of oxytocin takes place from the 2nd day after birth. Probably, these nuclei synthetize oxytocin in conjunction with the decline of placental maternal oxytocin.

Animals↗
PubMed2000

An association study between 5-HTTLPR polymorphism, COMT polymorphism, and Tourette's syndrome.

Several lines of evidence suggest that a genetic component underlies Tourette's syndrome (TS). We investigated both the role of the insertion/deletion polymorphism in the promoter region of the serotonin transporter gene (5-HTTLPR) and that of the Val-158-Met substitution in the catechol-O-methyl-transferase (COMT) gene in conferring susceptibility to TS. Fifty-two TS patients were recruited and compared with a control group of 63 healthy subjects. Neither a genotypic nor an allelic association was found; subdividing TS patients according to clinical variables, such as a co-diagnosis of obsessive-compulsive disorder (OCD) and a positive family history for obsessive compulsive disorder or tics, also failed to reveal a significant association. The lack of significance for 5-HTTLPR and COMT polymorphisms in conferring liability to TS does not exclude a role of different functional polymorphisms in genes coding for serotonergic or dopaminergic structures in the etiology of TS. In fact, TS is a complex disorder and these genes most likely have only a minor genetic effect in its etiology.

Adult↗