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1.
Microchem J ; 133: 614-621, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29081543

RESUMO

A Rancieite type material (K2Mn4O9) nanomaterial was synthesized and tested for the removal of chromium (III) and chromium (VI) from aqueous solutions. The synthesized nanomaterial was characterized using powder XRD and SEM. XRD showed weak diffraction peaks at only at the angles associated with K2Mn4O9. The SEM corroborated that the nanoparticles were present; however, the nanoparticles were clustered into larger aggregates. Batch studies were performed to determine the optimum pH, capacity, time dependency, interferences, and the thermodynamics of the binding. The optimum pH for the binding of Cr(III) and Cr(VI) were determined to be pH 5 and pH 2, respectively. Isotherm studies were performed at temperatures of 4 , 25 , and 45 for Cr(III) and Cr(VI) and showed binding capacities of 21.7 mg/g, 36.5 mg/g, 41.8 mg/g for Cr(III). The Cr(VI) binding capacities were 4.22 mg/g, 4.08 mg/g, and 3.25 mg/g at the respective temperatures. The thermodynamic studies showed that the binding processes for the reactions were spontaneous and endothermic, with a ΔH was 17.54 kJ/mol for Cr(III) and 6.05 kJ/mol for Cr(VI). The of sorption for Cr(III) were determined to be -3.88 kJ/mol, -5.83 kJ/mol and -7.03 kJ/mol at the aforementioned temperatures. The ΔG values for the Cr(VI) sorption were determined to be -4.89 kJ/mol, -5.64 kJ/mol, and -6.05 kJ/mol. In addition, the ΔS values for Cr(III) and Cr(VI) were determined to be 77.92 J/mol and 39.49 J/mol, respectively. The thermodynamics indicate that the binding of Cr(III) and Cr(VI) is spontaneous and endothermic.

2.
Nat Genet ; 10(2): 202-7, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7663516

RESUMO

Congenital generalized hypertrichosis (CGH) is a rare, fully penetrant X-linked dominant trait previously described in a single, multigenerational Mexican family. CGH is a visually striking phenotype characterized by excessive facial and upper torso hair in males and by less severe asymmetric hairiness in females. We have found significant evidence for linkage with several markers from the long arm of the X chromosome. Recombinant chromosomes place the CGH gene within a 22 cM interval between DXS425 and DXS1227 in Xq24-Xq27.1. The localization of a gene for CGH represents the first step towards the isolation of genes involved in hair growth pattern, particularly those involved in restriction of areas in humans.


Assuntos
Hipertricose/genética , Cromossomo X , Criança , Mapeamento Cromossômico , Feminino , Genes Dominantes , Ligação Genética , Genótipo , Humanos , Masculino , Linhagem , Polimorfismo de Fragmento de Restrição
3.
Nat Genet ; 2(4): 330-4, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1303289

RESUMO

Familial Alzheimer's disease (FAD) has been shown to be genetically heterogeneous, with a very small proportion of early onset pedigrees being associated with mutations in the amyloid precursor protein (APP) gene on chromosome 21, and some late onset pedigrees showing associations with markers on chromosome 19. We now provide evidence for a major early onset FAD locus on the long arm of chromosome 14 near the markers D14S43 and D14S53 (multipoint lod score z = 23.4) and suggest that the inheritance of FAD may be more complex than had initially been suspected.


Assuntos
Doença de Alzheimer/genética , Cromossomos Humanos Par 14 , Idoso , Alelos , Precursor de Proteína beta-Amiloide/genética , Sequência de Bases , Mapeamento Cromossômico , DNA/genética , Feminino , Marcadores Genéticos , Humanos , Escore Lod , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Linhagem
4.
Science ; 216(4546): 639-40, 1982 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-6461922

RESUMO

Electrophoretic study of phosphoglucomutase (PGM) in human milk revealed different patterns that can be explained by the existence of a locus distinct from the common PGM1, PGM2, and PGM3. One hundred and forty samples were tested and the results showed four different alleles of PGM4 whose frequencies were under Hardy-Weinberg equilibrium.


Assuntos
Leite Humano/enzimologia , Fosfoglucomutase/genética , Alelos , Eritrócitos/enzimologia , Feminino , Regulação da Expressão Gênica , Humanos , Isoenzimas/genética , Fenótipo
5.
Genet Couns ; 18(1): 85-97, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17515304

RESUMO

We describe two unrelated patients and the mother of one of them showing clinical and radiological features as those previously described in the spondyloepiphyseal dysplasia-brachydactyly and distinctive speech (SED-BDS, also named Fantasy Island syndrome or Tattoo dysplasia) clinically characterized by short stature with acral shortness, distinctive face, mild blepharophimosis, upslanted palpebral fissures, abundant eyebrows and eyelashes, thick and abundant hair and coarse voice; and radiologically by brachymetacarpalia, brachymetatarsalia and brachyphalangia of all fingers and toes, short and broad long bones with normal morphology and small pelvis. The clinical and radiological features present in mother and son suggest a probable autosomal dominant mode of inheritance and variable expressivity.


Assuntos
Anormalidades Múltiplas , Dedos/anormalidades , Distúrbios da Fala , Dedos do Pé/anormalidades , Anormalidades Múltiplas/genética , Adolescente , Adulto , Pré-Escolar , Nanismo/genética , Fácies , Feminino , Doenças Genéticas Ligadas ao Cromossomo X , Cabelo , Humanos , Masculino , Distúrbios da Fala/genética , Síndrome
6.
Hum Mutat ; 15(1): 116-7, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10612837

RESUMO

The factor IX gene (F9) is a valuable model for studying germ-line mutations. Nine mutations were detected in nine Mexican patients with hemophilia B by direct sequencing using genomic amplification with transcript sequencing (GAWTS): six single base changes, one micro-deletion, and two large deletions. Germline origins of mutations were found in three of six families with sporadic cases. Curiously, the four independent single base substitutions which were not at CpG dinucleotides occurred at only two different nucleotide positions (17,678 and 17,747) one transition and one transversion at each. The two remaining substitutions were identical changes at a CpG dinucleotide, but were determined to be independent by germline origin analysis. A statistical analysis suggests that the independent recurrence of mutations at these locations may reflect an unusual aspect of F9 mutagenesis in the Mexican population. These data raise the possibility of population-specific differences in human germline mutations.


Assuntos
Fator IX/genética , Mutação em Linhagem Germinativa , Hemofilia B/genética , Feminino , Deleção de Genes , Humanos , Masculino , México , Mutação Puntual
7.
J Invest Dermatol ; 113(6): 954-9, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10594736

RESUMO

Papular atrichia is an autosomal recessive disorder characterized clinically by the occurrence of universal congenital alopecia and disseminated papular lesions. Recently, mutations in the human hairless (HR) gene have been reported in Irish and Arab Palestinian families with papular atrichia. We have studied two further kindreds with this clinical phenotype from other ethnic backgrounds. For mutation detection the complete coding region as well as exon-intron boundaries of the HR gene were sequenced. The first family is a Mexican family with clinically typical papular atrichia. Sequencing identified a homozygous deletion of 4 bp in exon 7 (2001delCCAG) leading to a premature stop codon in exon 8. The second family is a South Tyrolian family with affected individuals showing papular atrichia and retardation of bone age during childhood. All affected individuals were identified as homozygous for an A-->G transition at nucleotide position 2909 (exon 14) leading to an amino acid change of asparagine to serine in codon 970 (Asn970Ser). These data provide further evidence for the involvement of hairless mutations in papular atrichia. In addition, these findings suggest that the hairless protein is not only involved in hair development but also in the process of ossification during development.


Assuntos
Alopecia/congênito , Alopecia/genética , Mutação da Fase de Leitura , Mutação de Sentido Incorreto , Adulto , Feminino , Humanos , Masculino , Polimorfismo Genético
8.
Eur J Hum Genet ; 7(3): 357-62, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10234512

RESUMO

Alleles of the CAG and the GGC repeat in the first exon of the human androgen receptor (AR) gene have been shown to be associated with the risk of (advanced) prostate cancer. These studies had been carried out in the United States. We have analysed these polymorphisms in a French-German collection of 105 controls, 132 sporadic cases, and a sample of prostate cancer families comprising 85 affected and 46 not affected family members. The allele distributions were very similar in all four groups and chi square statistics on contingency tables did not detect any significant differences. The relative risk (odds ratio, OR) were calculated using logistic regression and did not reach significance despite sufficient numbers of patients and controls. Typical results were OR = 1.007; 95% Confidence Interval (CI) 0.97-1.1, P = 0.87 for CAG as continuous variable and OR = 1.2 (95% CI 0.7-2.0), P = 0.47 for CAG classes < 22 and > = 22 repeats. Similar results were obtained for subgroups defined by age or Gleason score. We conclude that these polymorphisms can not be used as predictive parameters for prostate cancer in the French or German population.


Assuntos
Neoplasias da Próstata/genética , Receptores Androgênicos/genética , Repetições de Trinucleotídeos , Idoso , Idoso de 80 Anos ou mais , Alelos , França , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade
9.
Am J Med Genet ; 51(3): 213-5, 1994 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-8074146

RESUMO

Recently a distinct spondyloepimetaphyseal dysplasia (SEMD) was reported in three members of a Jewish family. We present a 3.5-year-old Mexican boy with disproportionate short stature, peculiar face, short neck, small chest, abdominal distension, lumbar lordosis, short limbs, marked genua vara, and joint laxity. Roentgenologic findings include short long bones, wide and flared metaphyses with irregularities, delayed epiphyseal ossification, platyspondyly and morphological changes of vertebral bodies and fibular overgrowth. The striking resemblance of this patient to those previously reported confirms this form of SEMD as a distinct entity. Autosomal recessive inheritance is supported and the designation SEMD Shohat type is proposed.


Assuntos
Anormalidades Múltiplas/genética , Fíbula/anormalidades , Osteocondrodisplasias/genética , Pré-Escolar , Nanismo/congênito , Genes Recessivos , Humanos , Hipertrofia , Instabilidade Articular , Articulação do Joelho/fisiopatologia , Lordose/genética , Masculino , Osteocondrodisplasias/patologia
10.
Am J Med Genet ; 47(4): 526-8, 1993 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-8256816

RESUMO

The Schwartz-Jampel syndrome (SJS) is an autosomal recessive disorder of myotonia, short stature, "mask-like" face, blepharophimosis, stiff joints, spinal malalignment, and pectus carinatum. The authors report on a 10-year-old girl with expressionless face, blepharophimosis, mild thoracic asymmetry, and myotonic electromyographic pattern, but without osteoarticular, spinal, and statural involvement. This appears to be one of the mildest form of SJS described so far. Contiguous genes could be an explanation for this and other atypical cases of SJS.


Assuntos
Osteocondrodisplasias/genética , Estatura , Osso e Ossos/anormalidades , Pré-Escolar , Feminino , Humanos , Articulações/anormalidades , Osteocondrodisplasias/patologia , Coluna Vertebral/anormalidades
11.
Am J Med Genet ; 5(2): 179-88, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-6772027

RESUMO

Three sibs from a Mexican mestizo family affected with a spondylo-epi-metaphyseal dysplasia were studied. The clinical, radiological, and genetic findings were similar to those previously described in Venezuelan Indians of the Irapa tribe. The present patients permit confirmation of the syndrome and provide evidence for autosomal recessive inheritance. Genetic drift is postulated.


Assuntos
Nanismo/genética , Mucopolissacaridose IV/genética , Adolescente , Criança , Feminino , Frequência do Gene , Genes Recessivos , Humanos , Masculino , México , Fenótipo , Síndrome
12.
Am J Med Genet ; 20(4): 677-84, 1985 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3993688

RESUMO

A t(X;3) (q26;q13.2) was found in three generations of a family. Female carriers exhibited normal reproductive function, whereas all three postpuberal male carriers showed spermatogenesis arrest at meiosis I. Additionally, a 2 3/12-year-old girl had duplication 3qter resulting from an adjacent-1 segregation.


Assuntos
Cromossomos Humanos 1-3 , Oligospermia/genética , Translocação Genética , Cromossomo X , Adolescente , Adulto , Pré-Escolar , Aberrações Cromossômicas , Bandeamento Cromossômico , Feminino , Heterozigoto , Humanos , Cariotipagem , Linfócitos/ultraestrutura , Masculino , Meiose , Linhagem , Espermatogênese , Espermatozoides/citologia , Testículo/citologia
13.
Am J Med Genet ; 69(4): 380-2, 1997 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-9098486

RESUMO

We carried out molecular analysis of 80 chromosomes from 40 unrelated Mexican patients with a diagnosis of cystic fibrosis. The study was performed in two PCR steps: a preliminary one to identify mutation delta F508, the most frequent cause of cystic fibrosis worldwide, and the second a reverse dot-blot with allele-specific oligonucleotide probes to detect 15 additional common mutations in the Caucasian population. A frequency of 45% for delta F508 was found, making it the most common in our sample of Mexican patients. Another five mutations (G542X, 3,849 + 10 kb C-->T, N1303K, SN549N, and 621 + 1 G-->T) were detected, and those accounted for 11.25%. The remaining mutations (43.75%) were undetectable with the methodology used.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/genética , Humanos , México , Mutação
14.
Am J Med Genet ; 69(2): 138-51, 1997 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-9056550

RESUMO

The hypertrichosis and osteochondrodysplasia syndrome is a rare entity with clinical findings including macrosomia at birth cardiomegaly. Autosomal recessive inheritance is presumed based on the report of two affected sibs born to healthy parents. Here we report on four new patients with their follow-up data, as well as on one of the four cases from the original report. Comparison of all eight cases indicates that they share 50% of clinical and radiological changes. This report contributes to the further delineation of this newly recognized syndrome.


Assuntos
Anormalidades Múltiplas/genética , Cardiomegalia/congênito , Hipertricose/congênito , Osteocondrodisplasias/congênito , Adolescente , Cardiomegalia/diagnóstico , Cardiomegalia/genética , Criança , Pré-Escolar , Feminino , Humanos , Hipertricose/diagnóstico , Hipertricose/genética , Masculino , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/diagnóstico por imagem , Osteocondrodisplasias/genética , Fenótipo , Radiografia , Síndrome , Raios X
15.
J Clin Pathol ; 36(6): 697-700, 1983 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6853734

RESUMO

A new fluorimetric method for the quantification of red blood cell (RBC) sorbitol dehydrogenase is described. It is based on the oxidation of sorbitol to fructose, in presence of NAD+, catalysed by the RBC-sorbitol dehydrogenase. The quantity of NADH formed is then measured in a filter fluorimeter. Comparison with an indirect spectrophotometric assay yielded good correlation; however, the present method offers several advantages: it is more rapid, simple and inexpensive. It should be useful to screen for sorbitol dehydrogenase deficiency in large numbers of individuals, particularly patients with diabetes or cataracts.


Assuntos
Eritrócitos/enzimologia , L-Iditol 2-Desidrogenase/sangue , Desidrogenase do Álcool de Açúcar/sangue , Fluorometria/métodos , Humanos , Cinética , Espectrofotometria
16.
FEMS Immunol Med Microbiol ; 22(4): 303-8, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9879921

RESUMO

Each year cholera epidemics occur in various places around the world. Though there is no effective vaccine against cholera, people who recover from an infection usually have prolonged immunity to the disease. Sera from convalescent patients contain antibodies to a number of outer membrane proteins (OMPs) of V. cholerae. We isolated several OMPs (43, 42, 30, and 22 kDa) from V. cholerae V86 E1 Tor Inaba, sequenced their amino-termini, and generated hyperimmune sera against them in rabbits. Antisera to the 43-, 42-, and 22-kDa OMPs, but not the preimmune sera, significantly reduced V. cholerae-induced fluid secretion seen in rabbit intestinal loops challenged with the homologous strain. In addition, a combination of antisera to the different OMPs reduced the fluid secretion induced by challenge with heterologous V. cholerae Ogawa and O139 strains. These results have significance in the development of vaccines to V. cholerae, as the hyperexpression of these OMP encoding genes in vaccine strains may improve the efficacy of cholera vaccines.


Assuntos
Proteínas da Membrana Bacteriana Externa/imunologia , Proteínas de Escherichia coli , Vibrio cholerae/imunologia , Adesinas Bacterianas/imunologia , Adesinas Bacterianas/isolamento & purificação , Sequência de Aminoácidos , Animais , Proteínas da Membrana Bacteriana Externa/isolamento & purificação , Cólera/imunologia , Cólera/prevenção & controle , Feminino , Dados de Sequência Molecular , Coelhos
17.
Arch Dermatol ; 114(12): 1807-9, 1978 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-153732

RESUMO

Thirteen members of a family had multiple comedones. Three other relatives were also ascertained to be affected. This peculiar dermatosis affected both sexes and was present in one individual as young as 10 years of age. The lesions were more numerous in male family members, increasing in number with age. The pedigree showed a definite pattern of autosomal dominant inheritance.


Assuntos
Acne Vulgar/genética , Genes Dominantes , Acne Vulgar/patologia , Adolescente , Adulto , Idoso , Criança , Aberrações Cromossômicas/genética , Transtornos Cromossômicos , Feminino , Humanos , Masculino , Linhagem , Pele/patologia
18.
Arch Med Res ; 24(2): 139-42, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-7903882

RESUMO

The frequency of alleles, intragenic (intron 18) and extragenic (DXS52) Bcl I RFLPs was investigated in a sample of the Mexican population. Altogether 33 X chromosomes at R8c locus and 30 at DXS52 locus were studied. The allele frequencies found at the F8c locus were similar to those reported in the majority of other populations. The observed heterozygosity for the intragenic and extragenic markers were 0.57 and 0.64, respectively. By using these two RFLPs 15 females at risk in five independent families with hemophilia A were investigated; ten of them could be identified and five excluded as carriers.


Assuntos
Triagem de Portadores Genéticos , Hemofilia A/genética , Alelos , Feminino , Frequência do Gene , Hemofilia A/epidemiologia , Humanos , Masculino , México/epidemiologia , Linhagem , Polimorfismo de Fragmento de Restrição
19.
Mutat Res ; 361(2-3): 107-12, 1996 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-8980695

RESUMO

The purpose of the present study was to investigate the range of micronucleated erythrocytes (MNE) in peripheral blood from splenectomized patients with and without genotoxic chemotherapy. The erythrocytes were stained with Wright and Giemsa for microscopic observation. To estimate the number of MNE, two series of 10000 erythrocytes per sample were analyzed and averaged. The results expressed as mean +/- standard deviation were as follows: control patients with genotoxic chemotherapy (n = 6) 2.5 +/- 1.5 (range 1 to 5 MNE); splenectomized patients with genotoxic chemotherapy (n = 7) 65.2 +/- 17.7 (range: 47-108) MNE and splenectomized patients without genotoxic chemotherapy (n = 13) 29.5 +/- 5.8 MNE; (range: 18.5-35.6). The MNE number in the patients treated with genotoxic chemotherapy depended on the type of drugs utilized: cyclophosphamide, mitoxantrone, vincristine, busulphan, cytosine arabinoside and hydroxyurea. Upon these results, it is suggested that splenectomized people could be useful in monitoring exposures, and the baseline MNE level would serve as each person's pre-exposure control when either chronic or acute exposure to environmental mutagens is investigated.


Assuntos
Antineoplásicos/efeitos adversos , Eritrócitos/ultraestrutura , Doenças Hematológicas/sangue , Micronúcleos com Defeito Cromossômico , Neoplasias/sangue , Adulto , Antineoplásicos/uso terapêutico , Feminino , Doenças Hematológicas/tratamento farmacológico , Doenças Hematológicas/cirurgia , Humanos , Masculino , Neoplasias/tratamento farmacológico , Neoplasias/cirurgia , Esplenectomia
20.
Mutat Res ; 413(3): 277-81, 1998 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-9651543

RESUMO

Diesel or its derivatives could have aneuploidogenic and/or clastogenic activity. Hence, the genotoxicity of diesel gases has been studied, considering exposure to them as potentially carcinogenic. The results obtained by different authors suggest the need to know the effects of direct and chronic exposure to diesel in humans, as in the case of the street workers called 'firebreathers' who fill their buccal cavity with diesel and then spread it to a burning torch many times during the day in order to give a 'dragon show' for 5 h a day and 6 days a week. The buccal samples of eight firebreathers were collected, processed and scored according to the criterion established by Tolbert et al., 1992 and then compared with positive and negative control groups. The results revealed that diesel was not micronucleogenic although it induces some nuclear abnormalities.


Assuntos
Gasolina/efeitos adversos , Mucosa Bucal/efeitos dos fármacos , Mutagênicos/efeitos adversos , Exposição Ocupacional/efeitos adversos , Adulto , Aberrações Cromossômicas , Feminino , Humanos , Masculino , Testes para Micronúcleos , Pessoa de Meia-Idade , Mucosa Bucal/ultraestrutura
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