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A Carnevale

Publications and source records attributed to A Carnevale.

At least 19 recordsLinked to original sources
PubMed2005

Trisomy of the short arm of chromosome 5 due to a de novo inversion and duplication (5)(p15.3 p13.3).

Partial trisomies of the short arm of chromosome 5 are uncommon. The first description was made by Lejeune et al., in 1964. It has been suggested that the critical region for 5p trisomy syndrome lies between 5p10 and 5p13. We report on a Mexican girl who developed severe mental retardation and generalized tonic clonic seizures at age 1 year. On physical examination at age 5 years, she had macrodolichocephaly, upslanted palpebral fissures, bilateral inner epicanthic folds, low nasal root, and malformed ears with posterior rotation which are clinical characteristics of 5p trisomy syndrome. The cytogenetic study with G bands and FISH with painting for chromosome 5 and with the cri-du-chat 5p15 unique sequence probe showed a duplication and inversion of 5p [46,XX, dup(5)(p15.3 p13.3)] which overlaps with the critical region for 5p trisomy syndrome. Our patient shares clinical characteristics with the patients described in the literature with involvement of this critical region. Both parents have normal karyotypes indicating the rearrangement is de novo. Only one patient has been reported in the literature with the same cytogenetic rearrangement as our patient, but this patient had a different phenotype. Since they only performed conventional cytogenetics and we performed FISH to confirm the diagnosis, the differences in the phenotypes could be explained by the presence of other genes involved in the rearrangement. The combined use of conventional and molecular cytogenetics in this case allows a more precise diagnosis and furthers knowledge in phenotype/genotype correlation.

Abnormalities, Multiple↗
PubMed2003

Antithyroid antibodies in the CSF: their role in the pathogenesis of Hashimoto's encephalopathy.

Antithyroid antibodies and circulating immune complexes (CIC) were found in the CSF of six patients with Hashimoto's encephalopathy (HE) but not in the CSF of 21 controls. The synthesis of autoantibodies and CIC was intrathecal and their titers were independent of the patients' clinical status or therapy. Their presence in the CSF of patients with acute or subacute encephalopathy may be useful in diagnosing HE.

Aged↗
PubMed2001

XV-2c/KM-19 haplotype analysis of cystic fibrosis mutations in Mexican patients.

We analyzed 97 unrelated Mexican cystic fibrosis (CF) patients and their first-degree relatives to study the association of XV2C/TaqI/KM19/PstI haplotypes with CF mutations in this population. Haplotype phases could be established in 148 CF and 110 normal chromosomes, and haplotype distributions of normal and CF chromosomes differed significantly (P < 0.001). DeltaF508 and G542X mutations accounted for 56% of CF chromosomes and were found to be associated with haplotype B in 97.2% and 72.7% of chromosomes, respectively. The haplotype distribution of CF chromosomes carrying other rare and unknown mutations was similar to that of normal chromosomes (P > 0.05), haplotypes A and C being the most frequent. This is in accordance with the extensive heterogeneity and the spectrum of mutations reported in Mexican CF patients. We also report the haplotype distribution of all informative chromosomes bearing rare mutations; some were found to be associated with previously reported haplotypes, whereas others were found on different haplotypes. Recombination or recurrence of mutations may explain these different associations, although other intragenic markers must be used to better understand the origin and dispersion of CF mutations in our country. XK haplotype analysis allowed carrier detection among sibs in 24.3% of families, showing that this method may be useful for carrier detection in populations with high allelic heterogeneity.

Cystic Fibrosis↗
PubMed2000

Ataxia-pancytopenia syndrome.

We report on a Mexican girl who developed cerebellar ataxia at age 3 years and pancytopenia at age 13 years. Cerebral computed tomography scan and magnetic resonance imaging showed evidence of severe cerebellar atrophy. Telangiectasias were not present; immunoglobulins and alpha-fetoprotein levels were normal. Cytogenetic studies showed no evidence of spontaneous chromosome aberrations, a normal rate of diepoxybutane (DEB) and mitomycin C (MMC)-induced chromosome aberrations, but an increased response to bleomycin. The phenotype support the diagnosis of ataxia-pancytopenia syndrome, although monosomy of chromosome 7 was not found in bone marrow. The cytogenetic studies suggest that this may be a chromosomal instability disorder.

Adult↗
PubMed2000

Spectrum of CFTR mutations in Mexican cystic fibrosis patients: identification of five novel mutations (W1098C, 846delT, P750L, 4160insGGGG and 297-1G-->A).

We have analyzed 97 CF unrelated Mexican families for mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Our initial screening for 12 selected CFTR mutations led to mutation detection in 56.66% of the tested chromosomes. In patients with at least one unknown mutation after preliminary screening, an extensive analysis of the CFTR gene by single stranded conformation polymorphism (SSCP) or by multiplex heteroduplex (mHET) analysis was performed. A total of 34 different mutations representing 74.58% of the CF chromosomes were identified, including five novel CFTR mutations: W1098C, P750L, 846delT, 4160insGGGG and 297-1G-->A. The level of detection of the CF mutations in Mexico is still lower than that observed in other populations with a relatively low frequency of the deltaF508 mutation, mainly from southern Europe. The CFTR gene analysis described here clearly demonstrated the high heterogeneity of our CF population, which could be explained by the complex ethnic composition of the Mexican population, in particular by the strong impact of the genetic pool from southern European countries.

Cystic Fibrosis↗
PubMed2000

Can seizures be the only manifestation of transient ischemic attacks? A report of four cases.

Several studies have investigated the frequency of epileptic seizures following ischemic strokes and transient ischemic attacks (TIAs). Little attention has been paid to the possibility that seizures may be precipitated by TIAs. We examined if seizures can be the only symptom of a TIA and how often this might occur. We performed a retrospective analysis of clinical charts and electroencephalograms of 160 consecutive patients evaluated for a first-ever seizure from January 1997 to December 1999 at Belluno General Hospital. From January to May 2000, 19 more first-ever seizure patients were evaluated directly. Four patients (2%) had seizures in the presence of important risk factors for ischemic stroke (atrial fibrillation in two patients, atrial fibrillation and ventricular mural thrombus in one patient, hemodynamically significant left carotid stenosis in one patient). Seizures were not accompanied by other neurological deficits or brain lesions on CT or MRI. As risk factors for brain ischemia are frequent in the general population not developing seizures, our results do not prove that the occurrence of seizures was more than casual in these patients. Yet they indicate that in a small percentage of patients, seizures can occur in a context highly suggestive of TIA, with no other focal deficits.

Aged↗
PubMed1999

Mexican geneticists' views of ethical issues in genetics testing and screening. Are eugenic principles involved?

Herein we discuss Mexican geneticists' views of ethical issues in genetic testing and screening, analyzing whether eugenic principles are involved in this activity. The information was obtained from a comprehensive survey on genetics, ethics, and society organized by Wertz and Fletcher in 1993, in which 37 nations participated. The responses to 21 questions from 64 out of 89 (72%) geneticists invited to participate are analyzed in this paper. The questions were practically the same as those answered recently by a group of Chinese geneticists (Mao X. Chinese geneticists' views of ethical issues in genetic testing and screening: evidence for eugenics in China. Am J Hum Genet 1998: 63: 688-695), who work in a country where the furtherance of eugenic principles is considered to be the goal of human genetics. We concluded that although there are many similarities in the answers from both countries, this is not indicative of Mexican geneticists pursuing eugenic goals because: a) there is no coercion involved; and b) there is no intention of improving the gene pool.

China↗
PubMed1998

Attitudes of Mexican geneticists towards prenatal diagnosis and selective abortion.

Prenatal diagnosis (PD) provides the physician information on whether the unborn fetus has a genetic or chromosomal disorder, and offers patients a new option: selective abortion. In the present study, we analyzed the answers Mexican geneticists provided to a few selected questions from a multinational survey designed by Wertz and Fletcher [1988: Am J Hum Genet 42:592-600]. The selected questions were related to the use of PD, the acceptance of selective abortion, and the self-reported directiveness of counselling following the diagnosis of a fetal anomaly. Our results show that the great majority of Mexican geneticists participating in the study agree with PD when medically indicated, but not on free demand. Specific cases stimulated the group on thinking more than the general statements provided in the survey. Although the majority agreed that PD should be available to all women, when faced with cases of nonmorbid maternal anxiety, paternity testing, and sex selection, the proportion of geneticists willing to perform the test decreased substantially. When counselling patients on a fetal anomaly, the minority would be as unbiased as possible, and this seems to be the tendency in developing countries where counselling, as stated in the respondents' comments, reflects the belief that the goal of genetics is the prevention of or opposition to abortion. Counselling was influenced by the severity of the disorder. The geneticists' personal attitude toward abortion in the same situations was stronger than when counselling others. Analysis of directiveness in counselling for fetal anomaly showed that older geneticists, with more years of experience in medical genetics, were more likely to be neutral. When counselling directively, the group showed an overall direction toward continuing affected pregnancies. However, older geneticists and those with more than 10 years of practice were more likely than their younger counterparts to counsel towards terminating affected pregnancies. In personal situations of fetal disorder, the general tendency was to abort; however, geneticists seeing more than 5 patients per week, and those who believe that religion is important, were more likely to reject abortion. The sample is representative of Mexican geneticists, and the main limitation of this study is that the geneticists have very little experience in PD, and that their responses were mostly based on theory. However, their opinions may influence the demand and the availability of PD and abortion, as well as the possibility of legalization of abortion on the basis of a fetal defect.

Abortion, Induced↗
PubMed1998

Mexican geneticists' opinions on disclosure issues.

Here we discuss the opinion on disclosure issues (respect for confidentiality) of Mexican professionals working in clinical genetics. The information was obtained from a comprehensive survey on genetics, ethics and society organized by Wertz and Fletcher in 1993, in which geneticists from 37 nations participated. The responses to 18 questions from 64 of 89 (72%) geneticists invited to participate were analyzed for this paper. The questions were directed to investigate: a) disclosure of clinically relevant information in several situations such as testicular feminization syndrome, mosaic de novo balanced translocation in a fetus, or accidental discovery of non-paternity; b) the protection of patient's privacy from the spouse or blood relatives; and c) confidentiality in cases with high genetic risk to relatives. The results reveal significant disparity between general responses related to disclosure of all clinically relevant information and specific responses in particular cases. In addition, professionals appear to give higher priority to protecting the spouse, blood relatives or public safety, rather than the patient's confidentiality.

Attitude of Health Personnel↗
PubMed1997

Chromosome instability with bleomycin and X-ray hypersensitivity in a boy with Nijmegen breakage syndrome.

We report on a Mexican boy with microcephaly, short stature, and a high frequency of chromosome aberrations with rearrangements involving chromosomes 7 and 14, typical of ataxia telangiectasia (AT) patients. He had neither ataxia nor telangiectasia, and his immunological status and serum alpha feto protein (AFP) level were normal. Bleomycin hypersensitivity, which has been demon-strated in AT patients, was tested in the patient using AT and normal subjects for comparison. The frequency of spontaneously occurring chromosome aberrations in lymphocyte cultures was significantly higher in the patient and the AT patient than in the normal subject. Four cells from the patient showed structural rearrangements involving chromosomes 7 or 14, with breakpoints typical for AT. When exposed to 5.0 micrograms bleomycin, the lymphocytes from the AT patient showed the highest sensitivity to this agent; our patient had an intermediate sensitivity. In both patients several rearrangements involving chromosomes 7 and 14 were scored, while none were observed in the normal subject. A colony survival assay (CSA) [Huo et al., 1994: Cancer Res 54:2544-2547], using a lymphoblastoid cell line (LCL) derived from our patient, showed a survival fraction (SF) of 7%, which is in the same range as in AT patients. The clinical picture, together with the cytogenetic and radiosensitivity results, suggests that our patient fits the variable spectrum of Nijmegen breakage syndrome.

Abnormalities, Multiple↗
PubMed1997

Counselling following diagnosis of a fetal abnormality: comparison of different clinical specialists in Mexico.

Most geneticists agree that counselling should be nondirective, and studies report that genetic counselling by geneticists is performed largely in a neutral style. However, couples at risk of having a child with a genetic condition may seek the advice of other physicians. The purpose of the present study was to describe the answers of four groups of specialists from Mexico City (internists, pediatricians, obstetricians, and neurologists) regarding how they would counsel a couple when prenatal diagnosis has shown that a fetus is affected by one of 17 different genetic disorders and to analyze the role of several variables in the development of their opinion. Our results show that physicians in these specialties are more likely to counsel directively than neutrally. Other variables did not influence the directiveness. With respect to direction of influence, internists, pediatricians, and neurologists are more likely to counsel terminating affected pregnancies than are obstetricians (P = 0.0002). Similarly, clinicians older than 37 years of age and those reporting that religion is not important to them counsel terminating affected pregnancies (P = 0.005 and P = 0.003, respectively). Physicians' gender and clinical experience with genetic diseases did not show statistically significant differences. Strong consensus among specialists was reached only on terminating pregnancies in anencephaly. A lowered and moderate consensus (51-75% agreement) was reached on continuing pregnancies with cleft lip and plate. A moderate measure of consensus for nondirective counselling was found among obstetricians regarding 14 of the 17 diseases in the study, whereas neurologists expressed a moderate measure of consensus on counselling the termination of pregnancies when the fetus was affected by neurological disorders. Hence, the approach to counselling was related in part to the fetal condition and in part to the clinician's specialty and age and the self-reported importance of religion. The data presented herein may not be representative of all Mexican physicians within the selected specialties; however, it is important to gather their opinions because they are involved in the care and treatment of genetic diseases and may have an important influence on the demand and availability of prenatal diagnosis and abortion.

Abortion, Induced↗
PubMed1997

Attitudes of Mexican physicians toward induced abortion.

The objective of this study was to analyze physicians' attitudes towards induced abortion with normal fetuses and fetuses known to have an abnormality in various degrees. A total of 193 physicians (internists, pediatricians, gynecologists and neurologists) answered a self-administered questionnaire. The questions were about voluntary abortion; voluntary abortion with malformed fetus; abortion because the fetus has anencephaly; and two questions were asked for the use of prenatal diagnosis and abortion in case of the fetus being the physician's child. The majority of physicians were male, over 35 years, religious and did not have experience with genetic diseases. Few physicians approved abortion of a normal pregnancy, 6 out of 10 agreed if the fetus was malformed, and this number increased to 8 or 9 out of 10 in cases of severe or lethal genetic disease. Gynecologists and neurologists were less in agreement with abortion when pregnancy is normal than the internists and pediatricians (7% vs. 20%). In general the physicians did not have consistent answers. Agreement for abortion was influenced by religious values.

Abortion, Induced↗
PubMed1997

Cerebrospinal-fluid ciliary neurotrophic factor in neurological patients.

We developed a double sandwich immunoassay for the dosage of ciliary neurotrophic factor (CNTF) in cerebrospinal fluid (CSF). The detection limit was 100 pg/ml. This assay was applied to human CSF samples from 14 normal subjects, 26 patients with multiple sclerosis (MS), 17 with Guillain-Barré syndrome (GBS) or chronic inflammatory demyelinating polyneuropathy (CIDP), and 22 with tumours of the central nervous system (CNS) or leucaemic meningosis (LM). Samples from normal control subjects and from patients with tumours did not contain detectable CNTF. Only 2 patients with LM were positive, and all the patients with inflammatory diseases of the CNS and peripheral nervous system were positive. The MS group presented a mean value of 240 pg/ml CNTF and the GBS/CIDP group a value of 430 pg/ml.

Astrocytoma↗
PubMed1997

Li-Fraumeni syndrome in pediatric patients with soft tissue sarcoma or osteosarcoma.

Family history of cancer and features of the Li-Fraumeni syndrome (LFS) were investigated in 42 patients with soft tissue sarcoma or osteosarcoma in a pediatric hospital in Mexico City, and compared with 42 non-cancer children. Six subjects with cancer were found among 204 first-degree relatives of cancer patients while there were none among 183 first-degree relatives of non-cancer children. In three families, the proband had two affected relatives, and the type of neoplasia as well as the age of onset suggested the clinical diagnosis of LFS. Our results show that 7.1% of our pediatric patients with soft tissue sarcoma or osteosarcoma may belong to LFS families. The authors encourage pediatric and adult oncologists to pay more attention to the history of cancer in nuclear families for eventual hereditary cancer syndrome identification and cancer prevention.

Adolescent↗
PubMed1996

Effect of hydroxyurea and normal plasma on DNA synthesis in lymphocytes from Fanconi anemia patients.

Fanconi anemia (FA) is characterized at the cellular level by a high frequency of spontaneous chromosomal aberrations; crosslinking agents cause an abnormal increase in the frequency of chromosomal damage, and semiconservative DNA synthesis is severely inhibited. Deoxyribonucleotides are needed in both semiconservative and repair DNA synthesis. To investigate the involvement of deoxyribonucleotide pools in the inhibition of DNA synthesis in FA, we evaluated the effect on FA lymphocytes of hydroxyurea (HU), an inhibitor of ribonucleotide reductase which is known to alter the intracellular levels of deoxyribonucleotides. To achieve this goal, lymphocyte cultures of 4 FA patients and 4 normal individuals were used. Cultures were treated with HU and/or mitomycin C and normal human plasma. All cultures were processed to detect the number of DNA synthesizing nuclei by autoradiography. Scoring of 2000 nuclei for each kind of culture every 6 h in the last 24 h of incubation showed that, in long incubation periods, DNA synthesis in FA is largely inhibited by HU and this hypersensitivity may be partially decreased by addition of normal human plasma. It is known that recovery from damage induced by HU involves several enzymes such as flavin oxido-reductase, superoxide dismutase and catalase which are involved in the production or scavenging of O2 radicals; FA cells are deficient in the detoxification of oxygen and this could explain the response of FA cells to HU.

Cells, Cultured↗
PubMed1996

Post-traumatic malignant glioma. Report of a case.

Only a few cases reported in the literature fulfil the currently established criteria for accepting the traumatic origin of some intracranial tumors. A case of post-traumatic glioma is presented. Several years after sustaining a commotive left parietal trauma, our patient developed symptoms of intracranial tumor. Neuroimaging (CT and MRI) showed a large neoplasia in the left temporo-parietal-occipital region, and stereotactic biopsy revealed a mixed glioma in continuity with the scar resulting from the trauma.

Brain Injuries↗
PubMed1996

G542X mutation in Mexican cystic fibrosis patients.

We analyzed the frequency of the G542X mutation in a sample of 76 Mexican cystic fibrosis patients and the genotype-phenotype correlation. The mutation was screened using PCR-mediated site-directed mutagenesis, and was present on 7.2% of the CF chromosomes. This frequency is significantly higher than the worldwide frequency according to the Cystic Fibrosis Genetic Analysis Consortium (3.4%, p < 0.01), and similar to that reported in Spain (8%), which is in accordance with the ethnic origin of the Mexican population. All patients carrying G542X on at least one allele had mild to moderate pulmonary disease. In patients with hepatobiliary involvement, the frequency of G542X chromosomes was higher than the frequency of the mutation in all the Mexican CF chromosomes.

Base Sequence↗