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1.
Urolithiasis ; 50(1): 79-85, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34424352

RESUMO

Retrograde Intra-Renal Surgery (RIRS) plays a primary role in renal stone treatment context. Energy, frequency and width of laser impulse can be modulated by surgeons to achieve better outcomes. In our study, patients with single renal stone sized 10-20 mm were retrospectively divided into two groups. Patients of Group 1 underwent RIRS with Low-Energy (LE) High-Frequency (HF) settings using Lumenis® 120-W high-power Ho:YAG laser. Patients of Group 2 (control) underwent RIRS using "standard" settings by means of Sphinx® Jr 30 W Ho:YAG system. Follow-up was conducted with a CT scan at 3 months after RIRS in both groups. Procedure success was defined as stone-free or presence of ≤ 4 mm fragments (Clinical Insignificant Residual Fragments-CIRF). A total number of 199 patients were included: 86 LE/HF RIRS (Group 1) vs 113 "conventional" RIRS (Group 2). Mean operative time was 56.6 (± 19.4) min in Group 1 vs 65.2 (± 25.2) min in Group 2 (p = 0.01). Mean hospitalization time was 2.5 ± 1.7 days for Group 1 vs 2.9 ± 3.2 days for Group 2 (p = 0.2). Peri-operative complications were counted: eight in Group 1 and 11 in Group 2 (p > 0.05). At 3-month control, stone-free rate was 69% (59/86 patients) in Group 1 vs 65% (73/113 patients) in Group 2 (p = 0.6). Success rate was 93% (80/86) in Group 1 in comparison to 82% (93/113) in Group 2 (p = 0.03). In conclusion, LE/HF RIRS seems to be a feasible and effective technique with a reduction of operative time and optimal results in terms of "stone-free" and "success" rates. Further studies are needed to ensure the validity of our results and to give evidence-based statements.


Assuntos
Cálculos Renais , Litotripsia a Laser , Litotripsia , Estudos de Casos e Controles , Humanos , Cálculos Renais/diagnóstico por imagem , Cálculos Renais/cirurgia , Litotripsia a Laser/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento , Ureteroscopia
2.
Curr Alzheimer Res ; 15(13): 1267-1275, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30210001

RESUMO

BACKGROUND: We describe the phenomenon of crossed cerebellar diaschisis (CCD) in four subjects diagnosed with Alzheimer's disease (AD) according to the National Institute on Aging - Alzheimer Association (NIA-AA) criteria, in combination with 18F-FDG PET and 11C-PiB PET imaging. METHODS: 18F-FDG PET showed a pattern of cerebral metabolism with relative decrease most prominent in the frontal-parietal cortex of the left hemisphere and crossed hypometabolism of the right cerebellum. 11C-PiB PET showed symmetrical amyloid accumulation, but a lower relative tracer delivery (a surrogate of relative cerebral blood flow) in the left hemisphere. CCD is the phenomenon of unilateral cerebellar hypometabolism as a remote effect of supratentorial dysfunction of the brain in the contralateral hemisphere. The mechanism implies the involvement of the cortico-ponto-cerebellar fibers. The pathophysiology is thought to have a functional or reversible basis but can also reflect in secondary morphologic change. CCD is a well-recognized phenomenon, since the development of new imaging techniques, although scarcely described in neurodegenerative dementias. RESULTS: To our knowledge this is the first report describing CCD in AD subjects with documentation of both 18F-FDG PET and 11C-PiB PET imaging. CCD in our subjects was explained on a functional basis due to neurodegenerative pathology in the left hemisphere. There was no structural lesion and the symmetric amyloid accumulation did not correspond with the unilateral metabolic impairment. CONCLUSION: This suggests that CCD might be caused by non-amyloid neurodegeneration. The pathophysiological mechanism, clinical relevance and therapeutic implications of CCD and the role of the cerebellum in AD need further investigation.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Cerebelo/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/complicações , Compostos de Anilina/metabolismo , Transtornos Cognitivos/diagnóstico por imagem , Transtornos Cognitivos/etiologia , Depressão/diagnóstico por imagem , Depressão/etiologia , Feminino , Fluordesoxiglucose F18/metabolismo , Lateralidade Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Estudos Retrospectivos , Tiazóis/metabolismo
3.
Braz J Biol ; 68(3): 671-9, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18833491

RESUMO

The present study is inspired by the great wealth of species exhibited by the ichthiofauna. Not only concepts and techniques of ecology deserve attention, but also knowledge in other biological areas, such as zoology and anatomy, are necessary. The intention of the present work is to discover the morphology of fish through the study of the digestive tract morphology, associating it to diet data, in order to better understand the biology of four fish species of the upper Paraná River floodplain. The samples were collected quarterly in the year 2000 with gillnets of different meshes. The stomach content was analyzed under a stereoscopic microscope and the frequencies of occurrence (FO) and volumetric (FV) and the alimentary index (IAi) were calculated. Various morphologic characteristics were analyzed and schematized using a light chamber. The species were grouped into two trophic guilds - insectivores (Astyanax altiparanae and Parauchenipterus galeatus) and piscivores (Serrasalmus marginatus and Hoplias aff. malabaricus). The first two, although consumers of insects, preyed on different alimentary groups, notably Hymenoptera in the case of A. altiparanae and Coleoptera in the case of P. galeatus. Serrasalmus marginatus and H. aff. malabaricus consumed mainly fishes. However, only pieces of prey were usually found in the stomach content of the first species, whereas whole fishes were found in the stomach content of the second. Astyanax altiparanae exhibited characteristics that allowed it to obtain food in several compartments of the water column. Similarly P. galeatus consumed food resources that were available in all aquatic compartments, although the abilities to capture, to manipulate and to absorb food differed, as shown by the importance of teeth plates and pharyngeal teeth. Serrasalmus marginatus and H. aff. malabaricus, although resembling each other in many aspects of the digestive tract morphology, differed in the strategies used to capture prey. The analysis showed that, according to the main food item of the diet, the species were grouped into two trophic guilds. However, those within the same category used different feeding methods, and similarity in items consumed does not imply the same group of morphological characteristics.


Assuntos
Comportamento Alimentar/fisiologia , Peixes , Conteúdo Gastrointestinal , Trato Gastrointestinal/anatomia & histologia , Animais , Brasil , Dieta/classificação , Peixes/anatomia & histologia , Peixes/classificação , Peixes/fisiologia , Rios
4.
Braz. j. biol ; 68(3): 671-679, Aug. 2008. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-493588

RESUMO

The present study is inspired by the great wealth of species exhibited by the ichthiofauna. Not only concepts and techniques of ecology deserve attention, but also knowledge in other biological areas, such as zoology and anatomy, are necessary. The intention of the present work is to discover the morphology of fish through the study of the digestive tract morphology, associating it to diet data, in order to better understand the biology of four fish species of the upper Paraná River floodplain. The samples were collected quarterly in the year 2000 with gillnets of different meshes. The stomach content was analyzed under a stereoscopic microscope and the frequencies of occurrence (FO) and volumetric (FV) and the alimentary index (IAi) were calculated. Various morphologic characteristics were analyzed and schematized using a light chamber. The species were grouped into two trophic guilds - insectivores (Astyanax altiparanae and Parauchenipterus galeatus) and piscivores (Serrasalmus marginatus and Hoplias aff. malabaricus). The first two, although consumers of insects, preyed on different alimentary groups, notably Hymenoptera in the case of A. altiparanae and Coleoptera in the case of P. galeatus. Serrasalmus marginatus and H. aff. malabaricus consumed mainly fishes. However, only pieces of prey were usually found in the stomach content of the first species, whereas whole fishes were found in the stomach content of the second. Astyanax altiparanae exhibited characteristics that allowed it to obtain food in several compartments of the water column. Similarly P. galeatus consumed food resources that were available in all aquatic compartments, although the abilities to capture, to manipulate and to absorb food differed, as shown by the importance of teeth plates and pharyngeal teeth. Serrasalmus marginatus and H. aff. malabaricus, although resembling each other in many aspects of the digestive tract morphology, differed in the strategies used ...


A grande riqueza de espécies exibida pela ictiofauna estimula a investigação e não apenas conceitos e técnicas de ecologia merecem atenção, mas também o conhecimento em outras áreas da biologia, como zoologia e anatomia, se fazem necessárias. A intenção do presente trabalho foi conhecer a morfologia de peixes através do estudo da morfologia do trato digestório, associá-lo aos dados de dieta, contribuindo para conhecer a biologia de quatro espécies de peixes da planície de inundação do alto rio Paraná. As amostras foram obtidas trimestralmente no ano 2000 com redes de espera de diferentes malhas. O conteúdo estomacal foi investigado sob microscópio estereoscópico, e as freqüências de ocorrência (FO) e volumétrica (FV) e o índice alimentar (IAi) calculados. Foram avaliadas diversas características morfológicas e esquematizadas sob câmara clara. As espécies foram agrupadas em duas categorias tróficas - insetívoros (Astyanax altiparanae e Parauchenipterus galeatus) e piscívoros (Serrasalmus marginatus e Hoplias aff. malabaricus). As duas primeiras, embora consumidoras de insetos, exploraram grupos alimentares diferentes, destacando-se Hymenoptera para A. altiparanae e Coleoptera para P. galeatus. Serrasalmus marginatus e H. aff. malabaricus consumiram peixes, entretanto apenas pedaços de presas foram mais freqüentes para a primeira e peixes inteiros para a segunda. Astyanax altiparanae exibiu características para obter o alimento em vários compartimentos da coluna d'água. Da mesma forma, P. galeatus aproveita os recursos disponíveis em todo o ambiente aquático, porém as características para capturar, manipular e aproveitar o alimento diferiram e para essa espécie ressalta-se a importância das placas dentígeras e dentes faríngeos. Serrasalmus marginatus e H. aff. malabaricus, embora se assemelhando em muitos aspectos da morfologia do trato digestório, diferiram nas estratégias de captura das presas. As análises demonstraram que, de acordo ...


Assuntos
Animais , Peixes , Comportamento Alimentar/fisiologia , Conteúdo Gastrointestinal , Trato Gastrointestinal/anatomia & histologia , Brasil , Dieta/classificação , Peixes/anatomia & histologia , Peixes/classificação , Peixes/fisiologia , Rios
5.
J Gynecol Obstet Biol Reprod (Paris) ; 35(5 Pt 1): 490-6, 2006 Sep.
Artigo em Francês | MEDLINE | ID: mdl-16940918

RESUMO

OBJECTIVES: To study risk factors for incident cervical intraepithelial neoplasia (CIN) among HIV-infected women. PATIENTS AND METHODS: Prospective study of a population of 97 HIV-infected women with normal Pap smear at inclusion. RESULTS: Fourteen CIN (diagnosed by colposcopy and confirmed with biopsy) were observed within a median follow-up of 38 months (13 CIN 1, one CIN 2). The incidence of cervical lesions was estimated to be 2%, 7% and 10% respectively at one year, two and three years after inclusion, The time to occurrence was very variable (ranging from 7 months to 6 years) among our patients. No known risk factors, in particular neither the CD4 cell count nor antiretroviral treatment, were identified to be associated with occurrence of CIN in our study population. CONCLUSION: Regardless of their immune status and HIV treatments, extensive and prolonged gynaecological follow up of HIV-infected women remains necessary.


Assuntos
Infecções por HIV/epidemiologia , Displasia do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Adulto , Feminino , Seguimentos , França/epidemiologia , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos
6.
J Cell Biol ; 149(1): 141-52, 2000 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-10747093

RESUMO

In this study we present evidence about the cellular functions of KIF4. Using subcellular fractionation techniques and immunoisolation, we have now identified a type of vesicle that associates with KIF4, an NH(2)-terminal globular motor domain kinesin-like protein. This vesicle is highly concentrated in growth cones and contains L1, a cell adhesion molecule implicated in axonal elongation. It lacks synaptic vesicle markers, receptors for neurotrophins, and membrane proteins involved in growth cone guidance. In cultured neurons, KIF4 and L1 predominantly localize to the axonal shaft and its growth cone. Suppression of KIF4 with antisense oligonucleotides results in the accumulation of L1 within the cell body and in its complete disappearance from axonal tips. In addition, KIF4 suppression prevents L1-enhanced axonal elongation. Taken collectively, our results suggest an important role for KIF4 during neuronal development, a phenomenon which may be related to the anterograde transport of L1-containing vesicles.


Assuntos
Transporte Axonal , Cinesinas/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso , Moléculas de Adesão de Célula Nervosa/metabolismo , Vacúolos/química , Vacúolos/metabolismo , Animais , Especificidade de Anticorpos , Axônios/metabolismo , Biomarcadores/análise , Células Cultivadas , Córtex Cerebral/citologia , Imunofluorescência , Cones de Crescimento/metabolismo , Membranas Intracelulares/química , Membranas Intracelulares/metabolismo , Cinesinas/química , Cinesinas/genética , Cinesinas/imunologia , Complexo Antígeno L1 Leucocitário , Camundongos , Microssomos/química , Microssomos/metabolismo , Peso Molecular , Oligonucleotídeos Antissenso/genética , Células Piramidais/citologia , Células Piramidais/embriologia , Células Piramidais/metabolismo , Ratos , Vesículas Sinápticas/química , Vesículas Sinápticas/metabolismo
7.
Chromosome Res ; 2(6): 428-38, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7530578

RESUMO

Human and Chinese hamster chromosomes were obtained from cells grown in the presence of 5-bromodeoxyuridine (BrdU) for (a) one replicative round, (b) two replicative rounds, (c) one replicative round followed by another round in thymidine and (d) the last period of synthetic phase. Untreated chromosomes and chromosomes treated with UV radiation after previous staining with 33258 Hoechst as photosensitizer were studied in order to investigate the mechanism(s) responsible for BrdU-induced sister chromatid differentiation (SCD). Metaphases were prepared by (1) standard methanol-acetic acid fixative for subsequent investigation with Giemsa or DNA-specific dyes such as ethidium bromide, acridine orange and monoclonal antibodies to double- or single-stranded DNA; (2) the procedure for observation under phase-contrast or electron microscopy; and (3) the cytospin method for subsequent immunoreaction with a monoclonal antibody to histone H2B. Our data exclude the possibility that the presence/absence of BrdU in the template strand might affect chromatin organization and thus resistance, while confirming that UV-induced DNA alteration is not sufficient, by itself, to explain SCD mechanism(s). That molecules other than DNA play a role in explaining SCD production is indicated by the fact that BrdU incorporation induces alterations in DNA-histone H2B interactions which, in turn, seem to produce structural variations in chromatin, possibly at the level of condensation, as monitored by phase-contrast and electron microscopy.


Assuntos
Cromátides/ultraestrutura , DNA/análise , Histonas/análise , Animais , Anticorpos Monoclonais , Bisbenzimidazol , Bromodesoxiuridina , Células CHO , Células Cultivadas , Cromátides/efeitos da radiação , Cromossomos/efeitos da radiação , Cromossomos/ultraestrutura , Cromossomos Humanos/efeitos da radiação , Cromossomos Humanos/ultraestrutura , Cricetinae , Replicação do DNA , Imunofluorescência , Humanos , Linfócitos/citologia , Linfócitos/efeitos da radiação , Raios Ultravioleta
8.
Eur J Histochem ; 37(4): 303-8, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-7510536

RESUMO

DNA strandness changes occurring during in situ hybridization were monitored using monoclonal antibodies. Our results show that: 1) RNase induces formation of single stranded DNA, 2) after denaturation-renaturation, single stranded DNA is found principally in centromeric areas, and 3) double stranded DNA is still observed after each step.


Assuntos
DNA/química , Hibridização In Situ , Humanos , Desnaturação de Ácido Nucleico , Renaturação de Ácido Nucleico , Ribonucleases
9.
Hereditas ; 112(2): 187-92, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-1694837

RESUMO

Restriction endonucleases (REs) have been widely used to produce banding patterns on chromosomes, but it remains uncertain to what extent the patterns are due to the sequence specificity of the enzymes, and to what extent chromatin structure influences the pattern of digestion. To throw light on this question, we have digested with restriction endonucleases unfixed chromosomes prepared in two different ways (isolated, and whole metaphase cells spread with a cytocentrifuge) and compared the results with those obtained on conventionally fixed chromosomes. Unfixed isolated chromosomes are easily destroyed by REs; after fixation with cold methanol, which produced minimal alteration to the chromatin structure, the chromosomes are resistant to the action of REs, and conventional methanol-acetic acid fixation is required to permit the induction of banding patterns by REs. Unfixed cytocentrifuge preparations, in which the chromosomes are still surrounded by cytoplasm, are much more resistant to the action of REs, and again banding patterns were only induced after methanol-acetic acid fixation. We conclude that the action of restriction endonucleases on chromosomes is strongly influenced by chromatin organisation, and that methanol-acetic acid fixation is required to permit the induction of conventional banding patterns on chromosomes.


Assuntos
Cromossomos Humanos/análise , Enzimas de Restrição do DNA/metabolismo , Bandeamento Cromossômico , Fixadores , Humanos , Coloração e Rotulagem
10.
Chromosoma ; 97(5): 356-62, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2470554

RESUMO

Fixed human metaphase chromosomes, whose DNA had been substituted with 5'-bromodeoxyuridine (BrdUrd) for two rounds of replication (TB/BB) or for one round in BrdUrd followed by another round in thymidine (TT/BT), were treated with ultraviolet light (UV), in the presence or in the absence of 33258 Hoechst, to produce sister chromatid differentiation (SCD). Giemsa staining was compared with staining with monoclonal antibodies to double-stranded or single-stranded DNA. We confirmed that UV acts by debrominating BrdUrd-stubstituted DNA but showed that debromination alone cannot explain all our findings. We postulated that UV-induced protein-protein cross-linking, occurring to a different extent in differently BrdUrd-substituted chromatids, may also be invoked in explaining our data. Lastly, the different behaviour of unifilarly substituted TB as opposed to BT chromatids in UV-treated chromosomes, allowed us to hypothesize that such chromatids may differ depending on whether or not newly synthesized DNA is formed on a BrdUrd-containing strand.


Assuntos
Anticorpos Monoclonais , Cromossomos/efeitos da radiação , DNA/efeitos da radiação , Metáfase , Bisbenzimidazol , Bromodesoxiuridina/farmacologia , DNA de Cadeia Simples/efeitos da radiação , Humanos , Cariotipagem , Coloração e Rotulagem , Raios Ultravioleta
11.
Cytogenet Cell Genet ; 50(1): 54-8, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2743818

RESUMO

Fresh and 6-day-old fixed chromosome spreads, both untreated and treated with various banding techniques and nucleases, were stained using monoclonal antibodies to double-stranded and single-stranded DNA. DNA in fixed chromosome preparations became progressively denatured with ageing. The staining pattern of untreated chromosomes with anti-double-stranded DNA antibodies (which resembles G-banding) was determined by the conformation of the chromosomal DNA.


Assuntos
Anticorpos Monoclonais/análise , Cromossomos Humanos/ultraestrutura , DNA de Cadeia Simples/imunologia , DNA/imunologia , Humanos , Imuno-Histoquímica , Cariotipagem , Masculino , Metáfase , Conformação de Ácido Nucleico
12.
Chromosoma ; 97(4): 334-8, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2707104

RESUMO

Human metaphase chromosomes, substituted with 5'-bromodeoxyuridine (BrdUrd) for one, two or three rounds of replication, were briefly pretreated with ultraviolet light (UV), in the presence of 33258 Hoechst, and subsequently digested with either exonuclease III or S1 nuclease. Pretreatment alone was not sufficient to induce sister chromatid differential staining (SCD), but allowed subsequent digestion with exonuclease III or S1. Such enzymes were found to induce SCD with ethidium bromide, as unifilarly BrdUrd-substituted chromatids (TB) were more resistant than bifilarly substituted chromatids (BB). Other experiments with DNase I or the AluI and HaeIII restriction endonucleases showed that only HaeIII was capable of inducing SCD by attacking BB more than TB chromatids preincubated with UV in the presence of Hoechst. SCD with exonuclease III/S1 nuclease seems to be due to (1) UV-induced DNA debromination occurring twice in BB as opposed to TB chromatids, and (2) alteration of chromatin protein structure occurring to a different extent in differently BrdUrd-substituted chromatids. Our findings with endonucleases, on the contrary, may depend on the capacity of enzymatic cleavage to cancel the different protein alterations induced differentially by UV in TB as opposed to BB chromatids.


Assuntos
Bromodesoxiuridina/análise , Desoxirribonucleases/metabolismo , Metáfase , Cromossomos , Replicação do DNA , Feminino , Humanos , Masculino , Fotólise
13.
Cancer Detect Prev ; 10(5-6): 401-3, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3568036

RESUMO

The presence of nonrandom chromosomal defects has been reported in a number of leukemias, lymphomas, and solid tumors. Primary karyotypic changes have been described in bladder carcinoma. We report the finding of chromosomal derivative markers 11 in three cases of bladder cancer. These markers were observed in all interpretable metaphases obtained by a direct method. The involvement of the short arm of chromosome 11 in the carcinogenetic process is discussed.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 11 , Neoplasias da Bexiga Urinária/genética , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade
14.
Clin Genet ; 30(5): 353-65, 1986 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3802554

RESUMO

Chromosome analysis in a 31-year-old woman referred for primary amenorrhea, revealed a very high incidence of chromosome aberrations. She had microcephaly and immunodeficiency. Her healthy parents were consanguineous (1/32) and a younger sister, also with primary amenorrhea, died when 20 years old with a malignant lymphoma. Chromosome studies were performed on lymphocytes and fibroblasts and in both tissues a high proportion of metaphases with multiple chromosome aberrations was found. Clonal and sporadic rearrangements, consisting of balanced and unbalanced translocations and dicentric chromosomes were more numerous than chromatid and chromosome breaks. In the lymphocytes the same unbalanced translocation t(8q;21q) was present in about 59% of the metaphases. Rearrangements involving chromosomes 7 and 14, similar to those described in patients with ataxia-telangiectasia were found, but with a lower frequency. Sister Chromatid Exchanges were not increased. Chromosome and chromatid abnormalities were enhanced after exposure of cells to mitomycin C but not after exposure to the radiomimetic drug bleomycin. Clinical and cytogenetic characteristics of the patient are compared with those of syndromes (Ataxia-Telangiectasia and Werner's syndrome) or isolated cases (Weemaes et al. 1981, Sperling 1983, Spinner et al. 1985) whose features are similar to those of our patient. This case might represent a new chromosome instability syndrome due to a recessive mutation.


Assuntos
Amenorreia/genética , Aberrações Cromossômicas , Síndromes de Imunodeficiência/genética , Microcefalia/genética , Adulto , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 21 , Cromossomos Humanos Par 7 , Cromossomos Humanos Par 8 , Consanguinidade , Feminino , Genes Recessivos , Humanos , Síndrome , Translocação Genética
15.
Hum Genet ; 73(1): 12-6, 1986 May.
Artigo em Inglês | MEDLINE | ID: mdl-3519430

RESUMO

Two previous single case reports from the literature showed the presence or absence of centromeric antigens at the site of the inactive centromeres in one (X;X) and in one (9;11) dicentric chromosome. We studied nine different dicentric chromosomes using anticentromeric antibodies and immunofluorescence techniques. In the four autosomal dicentrics the inactive centromere was consistently positive while the dicentrics composed of two X chromosomes were either positive or negative; one case of (X;Y) dicentric was negative. The results indicate that the X chromosome mode of replication may be involved in the suppression of immunofluorescence at the site of the inactive centromere and that one centromere of the dicentric chromosome may lose its function but conserve some of its antigenic properties. This indicates that not all these antigens play a rôle in the microtubules-centromere interaction.


Assuntos
Centrômero , Cromossomos , Mecanismo Genético de Compensação de Dose , Células Cultivadas , Centrômero/imunologia , Cromossomos/imunologia , Fibroblastos/ultraestrutura , Imunofluorescência , Humanos , Cariotipagem
16.
Ann Hum Genet ; 50(2): 153-62, 1986 05.
Artigo em Inglês | MEDLINE | ID: mdl-3435044

RESUMO

Three different samples of translocations were considered in an attempt to identify those chromosomal bands preferentially involved in variant Philadelphia chromosome (Ph1) translocations, and to compare them with bands preferentially broken in constitutional and sporadic translocations. The first sample included 204 cases of variant Ph1 translocations with 221 identified break-points (bp), the second consisted of 106 cases of non-Robertsonian constitutional translocations with 213 bp identified, and the third one of 185 bp identified in sporadic translocations found occasionally in single cells of subjects with normal karyotypes and without haematological disorders. A statistical analysis demonstrated that there are some bands preferentially broken in each of the samples, and this with a high level of significance (P less than 0.001). The analysis of the distributions of the chi 2 components permitted us to identify the 12 bands preferentially involved in variant Ph1 translocations and the 13 and 9 bands preferentially involved in constitutional and sporadic translocations, respectively. The comparison among the groups of preferential bp showed that the bands most involved in the three samples are different. Some theoretical problems related to the origin of the Ph1 chromosome are discussed.


Assuntos
Cromossomo Filadélfia , Translocação Genética , Bandeamento Cromossômico , Humanos , Estatística como Assunto
17.
Cancer Genet Cytogenet ; 16(4): 289-95, 1985 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-3842798

RESUMO

Cytogenetic studies on bladder carcinomas from two patients were carried out on preparations obtained by a direct method. The chromosome mode was 49 and 55, respectively. Several karyotypic changes were found in the tumors. Moreover, the analysis of Q-banded chromosomes revealed the presence in both cases of a chromosome 11p+. These rearranged chromosomes showed a very similar banding pattern. The finding of a der(11) chromosome marker in two patients is intriguing, and suggests the possibility of nonrandom chromosome changes in bladder carcinoma, as already found in other kinds of tumors. The occurrence of chromosome #11 aberrations in tumors of the urinary tract is discussed in connection with the current theories on oncogenesis.


Assuntos
Cromossomos Humanos 6-12 e X , Neoplasias da Bexiga Urinária/genética , Idoso , Aberrações Cromossômicas/patologia , Bandeamento Cromossômico , Transtornos Cromossômicos , Feminino , Humanos , Cariotipagem , Masculino , Pessoa de Meia-Idade
18.
Hum Genet ; 57(4): 345-50, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7286973

RESUMO

Eight patients are reported with a de novo extra inverted duplicated chromosome 15. The abnormal chromosome was considered to be the same in all cases, but its precise delineation remained uncertain and was defined as either 15pter leads to 15q12::15q12 leads to 15pter or 15pter leads to 15q11::15q13 leads to 15pter. Analysis with various techniques of the satellite regions of the bisatellited chromosomes demonstrated maternal derivation in six and paternal derivation in one of the seven families. A non-sister chromatid exchange between the two homologous chromosomes 15 is considered a likely origin of the inv dup(15) in the cases with maternal derivation; in the only case of paternal derivation, however, the abnormal chromosome originated from one single chromosome 15. The clinical findings confirm that patients with inv dup(15) have mental and developmental retardation and are frequently affected by seizures, while severe physical malformations are absent.


Assuntos
Inversão Cromossômica , Cromossomos Humanos 13-15 , Trissomia , Anormalidades Múltiplas/genética , Adolescente , Criança , Feminino , Transtornos do Crescimento/genética , Humanos , Lactente , Deficiência Intelectual/genética , Masculino , Fenótipo , Convulsões/genética
19.
Hum Genet ; 53(2): 165-7, 1980 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7358382

RESUMO

A case of trisomy 16q secondary to a paternal 16/18 translocation is described. A comparison of this case with the few other cases of trisomy 16q described in the literature indicates that trisomy for the long arm of chromosome 16 results in a severely affected phenotype and early death. Conversely, patient with trisomy 16p do not have gross abnormalities. We postulate that the prenatal lethality of full trisomy 16 is mainly due to the trisomy for the long arm.


Assuntos
Cromossomos Humanos 16-18 , Trissomia , Anormalidades Múltiplas/genética , Bandeamento Cromossômico , Transtornos do Desenvolvimento Sexual/genética , Humanos , Recém-Nascido , Masculino , Fenótipo , Translocação Genética
20.
Hum Genet ; 52(1): 55-67, 1979 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-294409

RESUMO

Six cases are reported of variant Ph' translocations found among 240 patients with Ph'-positive CML. Five cases had a three-chromosome rearrangement involving, in addition to chromosomes 9 and 22, chromosomes 7, 4, 2(two), and 3, respectively, and one case had a two-chromosome rearrangement 22/5. A review of the literature revealed that three- and two-chromosome variant Ph' translocations are observed with equal frequency. It is postulated that all variant translocations are indeed three-chromosome rearrangements, that the specific event for the formation of the Ph' chromosome is the reciprocal translocation 9/22, and that the transposition of regions 9q34 and 22 (q11toqter), plays a major role in the development of CML.


Assuntos
Cromossomos Humanos 21-22 e Y , Cromossomos Humanos 6-12 e X , Leucemia Mieloide/genética , Translocação Genética , Adulto , Idoso , Cromossomos Humanos 4-5 , Feminino , Humanos , Cariotipagem , Masculino , Pessoa de Meia-Idade
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