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1.
Braz J Biol ; 76(2): 444-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27007505

RESUMO

We report six new occurrence records of the bush dog Speothos venaticus, a widely distributed South American carnivore that is threatened with extinction. These records are accompanied by notes on the places where the records were made, such as vegetation type, date and information about the protection of areas. The records, obtained over the last 17 years in Paraná state, southern Brazil, offer an improved understanding of the species geographic range and the threats it faces and can enable better assessments of the conservation status of the species in southern Brazil.


Assuntos
Canidae , Espécies em Perigo de Extinção , Animais , Brasil/epidemiologia , Dinâmica Populacional/estatística & dados numéricos
6.
Braz. j. biol ; 76(2): 444-449, Apr.-June 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-781394

RESUMO

Abstract We report six new occurrence records of the bush dog Speothos venaticus, a widely distributed South American carnivore that is threatened with extinction. These records are accompanied by notes on the places where the records were made, such as vegetation type, date and information about the protection of areas. The records, obtained over the last 17 years in Paraná state, southern Brazil, offer an improved understanding of the species geographic range and the threats it faces and can enable better assessments of the conservation status of the species in southern Brazil.


Resumo Apresentamos seis novos registros de ocorrência do cachorro-do-mato-vinagre Speothos venaticus, um carnívoro sul Americano de ampla distribuição geográfica, porém ameaçado de extinção. Os registros são acompanhados de notas sobre os locais onde foram obtidos, tais como: tipo de vegetação, datas e informações sobre a proteção das áreas. Os registros, obtidos ao longo dos últimos 17 anos no Estado do Paraná, na região sul do Brasil, oferecem uma maior compreensão acerca da distribuição geográfica e das ameaças que a espécie enfrenta, permitindo melhores avaliações sobre o status de conservação desta espécie no sul do Brasil.


Assuntos
Animais , Espécies em Perigo de Extinção , Canidae , Brasil/epidemiologia , Dinâmica Populacional/estatística & dados numéricos
10.
Hum Genet ; 34(2): 119-24, 1976 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-1002136

RESUMO

A deletion of the Y chromosome at the distal portion of band q11 was found in 6 men with normal male habitus but with azoospermia. Five of them were found during a survey of 1170 subfertile males while the sixth was karyotyped because of slight bone abnormalities. These findings, together with a review of the literature, suggest that on the distal portion of the nonfluoresecent segment of the long arm of the Y, factors are located controlling spermatogenesis.


Assuntos
Cromossomos Sexuais , Espermatogênese , Adulto , Deleção Cromossômica , Humanos , Infertilidade Masculina/genética , Masculino , Aberrações dos Cromossomos Sexuais
11.
Hum Genet ; 39(3): 277-81, 1977 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-598835

RESUMO

An unbalanced X/Y translocation was found in a male child with malformed external genitalia and in his mother, who are respectively nullisomic and monosomic for the distal portion of Xp and have the translocated distal segment of Yq in excess. The loss of the distal portion of Xp is supposed to be the cause of the phenotypic abnormalities present in these subjects. The phenotype of our subjects is compared with those of the other cases of X/Y translocation described in the literature.


Assuntos
Genitália Masculina/anormalidades , Cromossomos Sexuais , Translocação Genética , Dermatoglifia , Humanos , Lactente , Cariotipagem , Masculino , Fenótipo
12.
J Med Genet ; 25(3): 173-80, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3351904

RESUMO

Instability of the heterochromatic centromeric regions of chromosomes 1, 9, and 16 associated with immunodeficiency was found in a four year old girl. Similar phenotypic and chromosomal abnormalities were described in a previous patient studied by us and in four other published cases. All these patients have facial anomalies in addition to combined immunodeficiency and chromosomal instability. Stretching of the heterochromatic centromeric regions of chromosomes 1, 16, and to a lesser extent, 9 and homologous and non-homologous associations of these regions were the most common cytogenetic findings in all the patients. Multi-branched configurations and whole arm deletions of chromosomes 1 or 16 or both were also found. Comparing clinical and chromosomal data we conclude that immunodeficiency, centromeric heterochromatin instability, and facial anomalies form a new syndrome, for which we propose the acronym ICF. A mutation interfering with the normal process of condensation of part of the centromeric heterochromatin is postulated as the basic chromosome defect in this syndrome.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 16/ultraestrutura , Cromossomos Humanos Par 1/ultraestrutura , Cromossomos Humanos Par 9/ultraestrutura , Ossos Faciais/anormalidades , Heterocromatina/ultraestrutura , Síndromes de Imunodeficiência/genética , Crânio/anormalidades , Pré-Escolar , Bandeamento Cromossômico , Feminino , Humanos , Mutação , Síndrome
13.
Chromosoma ; 55(1): 27-36, 1976 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-1253646

RESUMO

Anopheles atroparvus has two pairs of autosomes similar in length and morphology and two sex chromosomes with equal, heterochromatic, late replicating long arms with homologous C-, G-, and Q-bands. The short arm of the Y is shorter than that of the X and both are euchromatic. The mean number of chiasmata per cell in the male is 3.2. During mitosis there is a high grade of somatic pairing but X and Y, which form a heteropycnotic mass in the interphase nucleus, have a differential behaviour. The chronology of DNA replication was studied in spermatogonia and brain cells by autoradiography. It is hypothesized that the present sex chromosomes of A. atroparvus evolved by accumulation of sex determining factors and gene deterioration resulting in heterochromatinization of the long arms, followed by structural rearrangements.--The homology of the two sex chromosomes requires limited dosage compensation which is achieved either as in Drosophila by modifier genes or by accumulation on the short arm of the X, only of female determining factors which do not require dosage compensation.


Assuntos
Anopheles/citologia , Cromossomos/análise , Cromossomos Sexuais/análise , Animais , Evolução Biológica , Troca Genética , Feminino , Heterocromatina , Técnicas In Vitro , Cariotipagem , Masculino , Meiose , Mitose
14.
Chromosoma ; 49(4): 371-4, 1975.
Artigo em Inglês | MEDLINE | ID: mdl-48451

RESUMO

The long arms of the X and Y chromosomes of the mosquito Anopheles atroparvus (2n equals 6) are equal in length, synchronous in their late DNA replication and have homologous G AND Q bands. This indicates that differentiation of the two sex chromosomes was the consequence of a single deletion of an autosome to give the Y chromosome, not followed by the acquisition of differential heterochromatic blocks.


Assuntos
Anopheles/citologia , Cromossomos Sexuais/ultraestrutura , Animais , Autorradiografia , Heterocromatina/análise , Larva , Masculino , Análise para Determinação do Sexo , Espermatozoides/citologia , Coloração e Rotulagem , Timidina/metabolismo , Trítio
15.
Hum Genet ; 61(4): 364-8, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6818132

RESUMO

Aicardi's syndrome, which is characterized by agenesis of the corpus callosum, specific chorioretinal abnormalities, and defects of vertebrae and ribs, is considered a probable X-linked dominant trait with male lethality. All features of this syndrome were seen in a girl with a de novo balanced X/3 translocation (46,X,t(X;3)(p22;q12)). It is hypothesized that the clinical picture is the consequence of chromosome breakage within the Aicardi locus. Then, unusual X-inactivation patterns in blood and fibroblasts of this patient can be explained by somatic selection against cells with the Aicardi phenotype.


Assuntos
Anormalidades Múltiplas/genética , Agenesia do Corpo Caloso , Pré-Escolar , Cromossomos Humanos 1-3/ultraestrutura , Mecanismo Genético de Compensação de Dose , Anormalidades do Olho , Feminino , Fibroblastos , Humanos , Cariotipagem , Aberrações dos Cromossomos Sexuais , Esqueleto/anormalidades , Síndrome , Translocação Genética , Cromossomo X
16.
Hum Genet ; 51(2): 127-37, 1979 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-511139

RESUMO

Instability of the centromeric region of chromosome 1 and multibranched configurations formed by different numbers and combinations of arms of chromosomes 1, 9, and 16 were found in cultured lymphocytes of a 12-year-old male with combined IgA and IgE deficiency. No chromosome abnormalities were found in fibroblast cultures from the patient or in blood cultures from his parents. A possible effect on the frequency of the abnormalities of the almost continuous antibiotic treatment received by the patient was found both in vivo and in vitro, but no abnormalities were found in blood cultures from control subjects who received similar treatment. Interphase association of chromosomes 1, 9, and 16 and a high frequency of interchanges among the centromeric regions of these chromosomes due to the presence of a fragile site is assumed to be the cause of the abnormalities.


Assuntos
Cromossomos Humanos 1-3/ultraestrutura , Cromossomos Humanos 16-18/ultraestrutura , Cromossomos Humanos 6-12 e X/ultraestrutura , Imunoglobulina A , Imunoglobulina E , Síndromes de Imunodeficiência/genética , Criança , Aberrações Cromossômicas/genética , Transtornos Cromossômicos , Humanos , Cariotipagem , Masculino
17.
Graefes Arch Clin Exp Ophthalmol ; 224(3): 317-20, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3086186

RESUMO

The ocular and systemic abnormalities in a boy with ring chromosome 11 [46, XY/46, XY, r(11) (p 15.5----q25] are described. The ocular anomalies consisted of bilateral hypermetropia, microcornea, anterior chamber cleavage syndrome with prominent Wölfflin nodes, and cartwheel configuration of the anterior iris leaf. The systemic changes consisted of skeletal, muscular and articular defects, obesity, cryptorchidism, and mild mental retardation.


Assuntos
Anormalidades Múltiplas/genética , Aberrações Cromossômicas , Cromossomos Humanos 6-12 e X , Anormalidades do Olho , Deformidades Congênitas da Mão , Cromossomos em Anel , Testículo/anormalidades , Anormalidades Múltiplas/diagnóstico por imagem , Anormalidades Múltiplas/patologia , Criança , Bandeamento Cromossômico , Citogenética , Olho/patologia , Olho/fisiopatologia , Humanos , Cariotipagem , Linfócitos/fisiologia , Masculino , Microcefalia/complicações , Radiografia
18.
Ann Hum Genet ; 56(3): 273-8, 1992 07.
Artigo em Inglês | MEDLINE | ID: mdl-1449239

RESUMO

Interphase behaviour of centromeric heterochromatin of chromosomes 1 and 16 has been investigated in lymphocytes and fibroblasts of patients with ICF syndrome and of normal subjects with non-isotopic in situ hybridization, using the satellite II-related probe pHuR 195. We found evidence for interphase somatic pairing in ICF lymphocytes with a frequency higher than that found in normal cells. Lymphocytes of ICF patients showed nuclear protrusions and micronuclei and these nuclear abnormalities consistently involved a hybridization signal. Somatic pairing was also present in fibroblasts, but with frequencies similar in normal and ICF subjects. The fibroblasts do not have the major chromosomal abnormalities found in lymphocytes. The degree of heterochromatin condensation in fibroblasts was lower than that in lymphocytes and we postulate that the more decondensed state of chromocentres in the fibroblasts could be the reason for the absence of the major chromosomal abnormalities.


Assuntos
Aberrações Cromossômicas , Síndromes de Imunodeficiência/genética , Interfase , Núcleo Celular/patologia , Células Cultivadas , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 16 , Fibroblastos , Heterocromatina , Humanos , Cariotipagem , Linfócitos
19.
J Med Genet ; 29(4): 253-5, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1583646

RESUMO

An unbalanced complex chromosome rearrangement with 10 breakpoints resulting in four derivative chromosomes (1, 2, 4, and 11) was found in a girl with severe phenotypic abnormalities, many of which are characteristic of Williams syndrome. The patient was monosomic for the region 4q33----q35.1 and thus the mapping of the syndrome could tentatively be restricted to this region.


Assuntos
Anormalidades Múltiplas/genética , Aberrações Cromossômicas , Cromossomos Humanos Par 4 , Face/anormalidades , Encéfalo/anormalidades , Pré-Escolar , Mapeamento Cromossômico , Feminino , Cardiopatias Congênitas/genética , Humanos , Deficiência Intelectual/genética , Cariotipagem , Monossomia , Síndrome
20.
J Med Genet ; 26(7): 452-6, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2746618

RESUMO

Fibroblasts from a patient with ICF syndrome were grown in the presence of excess of nucleotides, in media with different amounts of folic acid, and with caffeine in an attempt to induce the chromosomal anomalies observed in lymphocytes. We induced despiralisation and breakages in the centromeric heterochromatin of chromosomes 1 and 16 but not associations and multibranching. We suggest that the absence of the major chromosomal anomalies in fibroblasts from patients with ICF might be the result of both a longer G2 in these cells and differential patterns of interphase heterochromatin associations in the two tissues.


Assuntos
Centrômero/ultraestrutura , Aberrações Cromossômicas/efeitos dos fármacos , Cromossomos Humanos Par 16 , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 9 , Cromossomos/ultraestrutura , Expressão Facial , Síndromes de Imunodeficiência/complicações , Mutação , Adenosina , Cafeína , Pré-Escolar , Feminino , Fibroblastos/ultraestrutura , Ácido Fólico , Humanos , Linfócitos/ultraestrutura , Timidina
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