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1.
J Intern Med ; 290(3): 646-654, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33999451

RESUMO

BACKGROUND AND OBJECTIVE: We aimed to evaluate the safety and outcomes of thrombectomy in anterior circulation acute ischaemic stroke recorded in the SITS-International Stroke Thrombectomy Register (SITS-ISTR) and compare them with pooled randomized controlled trials (RCTs) and two national registry studies. METHODS: We identified centres recording ≥10 consecutive patients in the SITS-ISTR with at least 70% of available modified Rankin Scale (mRS) at 3 months during 2014-2019. We defined large artery occlusion as intracranial internal carotid artery, first and second segment of middle cerebral artery and first segment of anterior cerebral artery. Outcome measures were functional independence (mRS score 0-2) and death at 3 months and symptomatic intracranial haemorrhage (SICH) per modified SITS-MOST. RESULTS: Results are presented in the following order: SITS-ISTR, RCTs, MR CLEAN Registry and German Stroke Registry (GSR). Median age was 73, 68, 71 and 75 years; baseline NIHSS score was 16, 17, 16 and 15; prior intravenous thrombolysis was 62%, 83%, 78% and 56%; onset to reperfusion time was 289, 285, 267 and 249 min; successful recanalization (mTICI score 2b or 3) was 86%, 71%, 59% and 83%; functional independence at 3 months was 45.5% (95% CI: 44-47), 46.0% (42-50), 38% (35-41) and 37% (35-41), respectively; death was 19.2% (19-21), 15.3% (12.7-18.4), 29.2% (27-32) and 28.6% (27-31); and SICH was 3.6% (3-4), 4.4% (3.0-6.4), 5.8% (4.7-7.1) and not available. CONCLUSION: Thrombectomy in routine clinical use registered in the SITS-ISTR showed safety and outcomes comparable to RCTs, and better functional outcomes and lower mortality than previous national registry studies.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Trombectomia , Artérias , Isquemia Encefálica/cirurgia , Procedimentos Endovasculares , Humanos , Hemorragias Intracranianas , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Resultado do Tratamento
2.
Curr Oncol ; 26(2): e180-e187, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31043825

RESUMO

Background: Variations in treatment choice, or late stage at first diagnosis, mean that, despite guideline recommendations, not all patients with hormone receptor (hr)-positive locally advanced or metastatic breast cancer (la/mbca) will have received endocrine therapy before disease progression. In the present study, we aimed to estimate the proportion of women with postmenopausal hr-positive la/mbca in the United States who are endocrine therapy-naïve. Methods: Women in the Optum Electronic Health Record (ehr) database with a breast cancer (bca) diagnosis (January 2008-March 2015) were included. Patient and malignancy characteristics were identified using structured data fields and natural-language processing of free-text clinical notes. The proportion of women with postmenopausal hr-positive, human epidermal growth factor 2 (her2)-negative (or unknown) la/mbca who had not received prior endocrine therapy was determined. Results were extrapolated to the entire U.S. population using the U.S. National Cancer Institute's Surveillance, Epidemiology, and End Results database. Results are presented descriptively. Results: In the ehr database, 11,831 women with bca had discernible information on postmenopausal status, hr status, and disease stage. Of those women, 1923 (16.3%) had postmenopausal hr-positive, her2-negative (or unknown) la/mbca, and 70.7% of those 1923 patients (n = 1360) had not received prior endocrine therapy, accounting for 11.5% of the overall population. Extrapolating those estimates nationally suggests an annual incidence of 14,784 cases, and a 5-year limited duration prevalence of 50,638 cases. Conclusions: A substantial proportion of women with postmenopausal hr-positive la/mbca in the United States could be endocrine therapy-naïve.


Assuntos
Neoplasias da Mama/epidemiologia , Receptor ErbB-2 , Receptores de Estrogênio , Receptores de Progesterona , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , Prevalência , Receptores de Esteroides , Estados Unidos/epidemiologia
3.
Arq. bras. med. vet. zootec ; 68(4): 983-990, jul.-ago. 2016. tab
Artigo em Português | LILACS, VETINDEX | ID: lil-792485

RESUMO

O objetivo deste estudo foi avaliar a morfometria intestinal por meio da inclusão de níveis de treonina digestível na dieta de codornas para corte em crescimento. O delineamento experimental adotado foi o inteiramente ao acaso, em esquema fatorial: quatro níveis nutricionais e três segmentos do intestino com dez repetições. Foram coletadas amostras dos três segmentos do intestino delgado. As variáveis estudadas foram área e altura das vilosidades intestinais, profundidade de cripta e relação vilo e cripta. No estudo da altura da vilosidade, foi obtida interação significativa para todas as idades estudadas. A profundidade da cripta em codornas de corte aos 21 dias de idade mostrou-se significativa para as variáveis inclusão de treonina na dieta e para a porção do intestino estudada. Na profundidade da cripta aos 42 dias, ficou evidenciada uma interação significativa entre níveis de inclusão de treonina na dieta e porção do intestino delgado. No estudo da relação altura de vilosidade e profundidade de cripta em codornas aos 21 dias de idade, foram encontrados resultados significativos para a interação tratamento e porção do intestino. Aos 21 e aos 42 dias de idade, a suplementação de 1,04 e 0,78%, respectivamente, de treonina digestível na dieta promove melhores resultados para morfometria intestinal.(AU)


The aim of the study was to evaluate intestinal morphology data by including different levels of threonine in the diet of meat quails in the growing phase. The experimental design was completely randomized in a factorial arrangement: four nutritional levels and three intestinal segments with ten repetitions. Samples were collected to obtain morphometry data (villi and crypt) of the three segments of the small intestine (duodenum, jejunum, and ileum). In the study of the intestinal villus height a highly significant interaction was obtained for all ages studied. A crypt depth was evidenced at 42 days with a significant interaction between levels of inclusion of threonine in the diet and small intestine. In the study of the relationship villus height and depth crypt quails at 21 days of age, the results were significant for the interaction treatment (T) and part of the intestine. At 21 and 42 days of age, supplementation of 1.04 and 0.78% respectively of threonine in the diet promotes better outcomes for intestinal morphology.(AU)


Assuntos
Animais , Fenômenos Fisiológicos da Nutrição Animal , Coturnix/fisiologia , Intestinos/anatomia & histologia , Treonina , Aminoácidos Essenciais , Aves Domésticas
4.
Poult Sci ; 93(5): 1130-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24795305

RESUMO

This study evaluated the effects of different levels of canola meal in broiler diets on growth performance, nutrient digestibility, and duodenal morphometry. A total of 320 one-day-old Cobb broilers were used in a 35-d experiment. A completely randomized design with 5 levels of canola meal (0, 10, 20, 30, and 40%) as a substitute for soybean meal was used with 8 replicates of 8 birds each. The basal diets were formulated based on corn and soybean meal to meet nutrient requirements of broiler chickens. The levels of canola meal were evaluated with a polynomial regression at 5% of significance. Weight gain and average BW showed a quadratic response (P = 0.03 and P = 0.04, respectively), decreasing with the addition of 40% canola meal. The apparent nutrient digestibility of DM (P < 0.0001), CP (P < 0.0001), and nitrogen-free extract (P < 0.0001) decreased linearly with increased levels of canola meal. A quadratic effect was observed for villus height (P = 0.003), decreasing up to a 20% inclusion of canola meal in the diet and increasing beyond that level. In conclusion, canola meal can be added up to 16.7% in diets for broilers without affecting the key variables of growth performance. It can be added up to 20% with no negative effect on the CP digestibility, but there was a linear decrease in the digestibility of DM and nitrogen-free extract with increased inclusion of canola meal. Additionally, a quadratic response to canola was observed for villus height with a maximum at 23.6% canola meal.


Assuntos
Brassica/química , Galinhas/fisiologia , Digestão , Duodeno/efeitos dos fármacos , Aumento de Peso/efeitos dos fármacos , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Galinhas/anatomia & histologia , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Relação Dose-Resposta a Droga , Duodeno/citologia , Mucosa Intestinal/citologia , Mucosa Intestinal/efeitos dos fármacos , Masculino , Distribuição Aleatória
6.
Arq. Inst. Biol. (Online) ; 77(4): 567-573, out.-dez. 2010. graf
Artigo em Português | VETINDEX, LILACS | ID: biblio-1391804

RESUMO

Este trabalho teve como objetivo determinar a prevalência de Escherichia coli produtoras de Shigatoxinas (STEC) e E. coli dos sorogrupos O157, O111 e O113 em rebanhos leiteiros do Município de Jaboticabal, SP, Brasil. A presença de sequências gênicas stx1, stx2e eae foi detectada pela reação em cadeia da polimerase (PCR) em amostras de fezes. Todas as amostras stx e eae positivas foram submetidas a uma nova reação de PCR para detecção das sequências rfb O157, O111 e O113. Observou-se uma alta prevalência (72,16%) de sequências stx nas fezes dos bovinos, sendo que o perfil genotípico encontrado com maior frequência foi o stx1 associado à stx2. Os coeficientes de prevalência das sequências rfb O157, O111 e O113 foram, respectivamente, 14,77%, 0,2% e 30,83%. Animais de todos os rebanhos (100%) apresentaram em suas fezes STEC e E. coli O113 e os sorogrupos O157 e O111 foram observados em 60,0% e 10,0% dos rebanhos, respectivamente. Concluiu-se que a alta prevalência de STEC detectada em rebanho leiteiro evidenciada nas fezes de bovinos desempenham um papel importante na contaminação ambiental e podem oferecer risco de agravo à saúde pública.


The purpose of this study was to determine the prevalence of Shigatoxigenic Escherichia coli (STEC) and serogroups O157, O111 and O113 in dairy cattle from Jaboticabal, state of São Paulo, Brazil. Feces samples were collected from 10 herds and assessed for the presence of the virulence genes stx1, stx2 and eae by polymerase chain reaction (PCR). All samples positive for stx and eae were submitted to a second PCR reaction targeting the sequences rfb O157, rfb O111 and rfb O113. A high prevalence of stx (72.16%) was detected in the fecal samples, the most frequent being stx1 associated to stx2. The prevalence of sequences rfb O157, rfb O111 and rfb O113 was 14.77%, 0.2% and 30.83%, respectively. STEC and serogroup O113 was identified in all herds (100%), and serogroups O157 and O111 were observed in 60% and 10% of the herds. In conclusion, the high STEC prevalence detected in dairy herds evidences that bovine feces might play an important role as a contamination source in the region of Jaboticabal.


Assuntos
Animais , Bovinos , Escherichia coli/classificação , Infecções por Escherichia coli/epidemiologia , Escherichia coli Shiga Toxigênica/isolamento & purificação , Fezes/microbiologia , Reação em Cadeia da Polimerase Multiplex/veterinária
7.
Arq. Inst. Biol. (Online) ; 77(4): 617-624, out.-dez. 2010. tab
Artigo em Português | VETINDEX, LILACS | ID: biblio-1391918

RESUMO

O objetivo deste trabalho foi determinar o número de coliformes totais, termotolerantes, Staphylococcus coagulase positivo e a presença de bactéria do gênero Salmonella no músculo, no tecido superficial, no trato gastrintestinal de peixes e na água de cultivo de pesque-pagues situados na microbacia do Córrego Rico, SP. Não foi detectado Staphylococcus coagulase positivo em nenhuma amostra de água e peixe. O número mais provável (NMP) de coliformes totais no peixe variou de 2,0 x 10 a >1,1 x 104 NMP.100 mL-1, na água de cultivo variou de 4,2 x 104 a > 2,4 x 105 NMP.100 mL-1. A contagem de coliformes termotolerantes no peixe variou de < 3 a 5,1 x 103 NMP.g-1, na água de cultivo variou de 3,8 x 102 a 2,0 x 104 NMP.100 mL-1. Não houve diferença estatística (P > 0,05) entre as populações de micro-organismos pesquisados na água, pele e trato gastrintestinal, o que reflete uma relação entre a presença dos micro-organismos na água e nesses dois locais analisados. Foi isolada Salmonella sp. em uma amostra de músculo e em duas amostras de trato gastrintestinal. O pescado pode ser veículo de contaminação cruzada, tendo como fonte dos micro-organismos a pele e o trato gastrintestinal para sua própria musculatura. Portanto, o monitoramento da qualidade da água é de suma importância para garantir a produção de peixes com boa qualidade.


The objective of this study was to determine the number of total and thermotolerant coliforms, coagulase-positive Staphylococcus, and the presence of bacteria of the genus Salmonella in the muscle, surface tissue, and gastrointestinal tract of fish, and in the pond water of fee-fishing establishments located in the Córrego Rico microwatershed in the state of São Paulo, Brazil. Coagulase-positive Staphylococcus was not detected in any sample of pond water or fish. The most probable number (MPN) of total coliforms in fish ranged from 2.0 x 10 to > 1.1 x 104 NMP.100 mL-1, while in pond water it ranged from 4.2 x 104 to > 2.4 x 105 NMP.100 mL-1. The count of thermotolerant coliforms in fish ranged from < 3 to 5.1 x 103 NMP.g-1, while in pond water it ranged from 3.8 x 102 to 2.0 x 104 NMP.100 mL-1. There was no statistical difference (P > 0.05) among the studied populations of microorganisms in pond water, surface tissue and gastrointestinal tract, which reflects a relationship between the presence of microorganisms in the water and in the two tissues analyzed. Salmonella sp. was isolated in one sample of muscle and in two samples of gastrointestinal tract. The fish can be a vehicle for cross contamination, having the gastrointestinal tract and the surface tissue as a source of microorganisms for its muscles. Therefore, monitoring the water quality is important to ensure the production of fish with good quality.


Assuntos
Animais , Salmonella/isolamento & purificação , Staphylococcus/isolamento & purificação , Coagulase/análise , Pesqueiros/normas , Peixes/microbiologia , Colimetria , Lagoas/microbiologia
8.
Food Chem Toxicol ; 45(4): 662-6, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17187912

RESUMO

Stevioside is a natural non-caloric sweetener extracted from Stevia rebaudiana (Bertoni) leaves. It has been widely used in many countries, including Japan, Korea, China, Brazil and Paraguay, either as a substitute for sucrose in beverages and foods or as a household sweetener. The aim of this work was to study its genotoxic potentiality in eukaryotic cells. Wistar rats were treated with stevioside solution (4mg/mL) through oral administration (ad libitum) and the DNA-induced damage was evaluated using the single cell gel electrophoresis (comet assay). The results showed that treatment with stevioside generates lesions in peripheral blood, liver, brain and spleen cells in different levels, the largest effect being in liver. Therefore, these undesired effects must be better understood, once the data present here point to possible stevioside mutagenic properties.


Assuntos
Ensaio Cometa/métodos , Diterpenos do Tipo Caurano/toxicidade , Glucosídeos/toxicidade , Edulcorantes/toxicidade , Animais , Dano ao DNA , Ratos , Ratos Wistar
9.
Mol Cell Biochem ; 293(1-2): 187-92, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16804638

RESUMO

Stevioside is widely used daily in many countries as a non-caloric sugar substitute. Its sweetening power is higher than that of sucrose by approximately 250-300 times, being extensively employed as a household sweetener, or added to beverages and food products. The purpose of this study was to ascertain stevioside genotoxic and cytotoxic potentiality in different biological systems, as its use continues to increase. Agarose gel electrophoresis and bacterial transformation were employed to observe the occurrence of DNA lesions. In addition to these assays, Escherichia coli strains were incubated with stevioside so that their survival fractions could be obtained. Results show absence of genotoxic activity through electrophoresis and bacterial transformation assays and drop of survival fraction of E. coli strains deficient in rec A and nth genes, suggesting that stevioside (i) is cytotoxic; (ii) could need metabolization to present deleterious effects on cells; (iii) is capable of generating lesions in DNA and pathways as base excision repair, recombination and SOS system would be important to recover these lesions.


Assuntos
Diterpenos do Tipo Caurano/toxicidade , Glucosídeos/toxicidade , Mutagênicos/toxicidade , Edulcorantes/toxicidade , DNA Bacteriano/efeitos dos fármacos , Eletroforese em Gel de Ágar , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/metabolismo , Plasmídeos/efeitos dos fármacos , Plasmídeos/metabolismo , Transformação Bacteriana
10.
Soc Psychiatry Psychiatr Epidemiol ; 40(1): 11-7, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15624069

RESUMO

BACKGROUND: There have been very few Brazilian epidemiological surveys of child mental health problems. The only recent survey to have used internationally recognised measures and diagnostic criteria was carried out in Southeast Brazil in a relatively prosperous setting where the population was predominantly urban and white. METHODS: The setting was an island community in Northeast Brazil that is rural, relatively poor and has a strong African heritage. In an initial phase, a simple random sample of 519 children aged 5-14 was assessed by screening questionnaires completed by parents, teachers and older children. In a second phase, a sub-sample of 100 children was selected for more detailed diagnostic assessments. RESULTS: Conduct and hyperactivity problems were commoner in boys; emotional symptoms were commoner in girls; and hyperactivity declined with age. By contrast with previously collected data from Southeast Brazil, there were more reported symptoms, but less resultant impact. Using a variety of indices, the rate of disorder on Ilha de Maré was around half that previously found in Southeast Brazil. CONCLUSION: The measures and diagnostic criteria that were employed appeared valid for use in Northeast Brazil, though there was evidence for consistent over-reporting of symptoms on the screening questionnaire. Rates of child mental health problems appear to differ substantially between sites, confirming the need for a multi-site Brazilian study of the prevalence of child psychiatric disorders.


Assuntos
População Negra/estatística & dados numéricos , Serviços de Saúde da Criança/estatística & dados numéricos , Inquéritos Epidemiológicos , Transtornos Mentais/etnologia , Transtornos Mentais/terapia , Serviços de Saúde Mental/estatística & dados numéricos , População Rural/estatística & dados numéricos , Adolescente , África/etnologia , Brasil/epidemiologia , Criança , Pré-Escolar , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Humanos , Masculino , Transtornos Mentais/epidemiologia , Inquéritos e Questionários
11.
J Hosp Infect ; 59(1): 19-26, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15571849

RESUMO

Studies on the genetic diversity of oxacillin-resistant coagulase-negative staphylococcal (CNS) isolates are important for the control and prevention of infections. The present study evaluated the clonal diversity of oxacillin-resistant Staphylococcus epidermidis (ORSE) and Staphylococcus haemolyticus (ORSH) strains, isolated from patients in nine Brazilian medical centres by using pulsed-field gel electrophoresis (PFGE) after digestion of bacterial DNA using SmaI. PFGE analysis of ORSE (N=44) and ORSH (N=25) strains showed the presence of 29 restriction profiles clustered in 16 PFGE types, and 21 distinct profiles in 15 PFGE types, respectively, indicating a large genetic diversity among isolates of both of these species. Among the ORSE isolates, 23 (52%) strains belonged to two predominant PFGE types (named A and B), which were observed in most of the hospitals assessed, indicating the spread of these PFGE types in hospitals located in Rio de Janeiro. The spread of PFGE types of ORSH was also detected in some of the hospitals investigated. The results show that PFGE is a suitable tool for epidemiological studies of oxacillin-resistant CNS, and can be used as a basis for infection control procedures for these multiresistant organisms.


Assuntos
Infecção Hospitalar/microbiologia , Eletroforese em Gel de Campo Pulsado/métodos , Genoma Bacteriano , Oxacilina , Infecções Estafilocócicas/microbiologia , Staphylococcus epidermidis/genética , Staphylococcus haemolyticus/genética , Proteínas de Bactérias/genética , Brasil/epidemiologia , Análise por Conglomerados , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle , Infecção Hospitalar/transmissão , Farmacorresistência Bacteriana/genética , Eletroforese em Gel de Campo Pulsado/normas , Estudos Epidemiológicos , Variação Genética/genética , Hospitais de Ensino , Hospitais Urbanos , Humanos , Controle de Infecções , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Filogenia , Reação em Cadeia da Polimerase/métodos , Prevalência , Mapeamento por Restrição , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/prevenção & controle , Infecções Estafilocócicas/transmissão , Staphylococcus epidermidis/isolamento & purificação , Staphylococcus haemolyticus/isolamento & purificação
12.
Toxicol Lett ; 151(3): 481-7, 2004 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-15261992

RESUMO

Plants have been related to our lives, being used as medicine, regardless of scientific evidence of side effects. This work analyses the toxicological effects of Chrysobalanus icaco L. aqueous extract, used in different pathologies. It was studied through: (i) alteration of plasmid pUC 9.1 topology; (ii) survival of bacterial strains submitted, or not, to previous treatment with SnCl2; (iii) transformation efficiency of E. coli strain by the treatment with the plasmid pUC 9.1. In (i), the treatment of the plasmid resulted in DNA single-strand breaks (SSB). A decrease of the lethal effect induced by SnCl2 in presence of the extract was found, while no C. icaco bacterial survival reduction was observed. The transformation efficiency of the plasmid was also reduced. Results suggest that the extract could present a potential genotoxic effect, as demonstrated either by the induction of SSB in plasmid or in transformation efficiency experiments. Finally, it presents an antioxidant action.


Assuntos
Chrysobalanaceae , Extratos Vegetais/toxicidade , Antioxidantes/farmacologia , Dano ao DNA , Escherichia coli/efeitos dos fármacos , Extratos Vegetais/farmacologia , Folhas de Planta , Plasmídeos/efeitos dos fármacos , Transformação Bacteriana/efeitos dos fármacos
13.
Artigo em Inglês | MEDLINE | ID: mdl-12109528

RESUMO

Allergic reactions to the pollen of trees is among the most prevalent allergic sensitivities. The cashew tree grows in abundance in the northeast region of the Brazil, mainly in Fortaleza city, in state of the Ceará. It flowers once a year between August and October. This is the first study conducted to establish the possible role of the cashew pollen extract in causing skin test reactivity in patients with allergic asthma. A stock solution of pollen extract was prepared with the standard weight/volume method for intradermal skin tests and for the protein content of the extract, estimated with the use of Folin phenol reagent and a spectrophotometer. Ten nonallergic volunteers and 80 subjects with allergic asthma, as documented by previous positive skin test reactions to various pollens, were studied. All of the 80 patients (100%) had positive test reactions (grade III and grade IV reactions). None of the control subjects (n = 10) had positive responses to the intradermal tests. This study provided us with knowledge of an additional pollen extract of the Anacardium occidentale, which could provoke skin test reactivities in asthmatic individuals from the northeastern area of Brazil. The results suggest a relationship between the period of flowering of the cashew tree and the increased number of allergic asthma cases.


Assuntos
Alérgenos/imunologia , Anacardium/imunologia , Asma/imunologia , Pólen/imunologia , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Testes Intradérmicos , Masculino , Pessoa de Meia-Idade , Extratos Vegetais/imunologia , Proteínas de Plantas/análise
14.
Cytobios ; 98(389): 137-47, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10533268

RESUMO

Chromosomal analysis of Kunsia tomentosus showed a karyotype with 2n = 44, constituted by 21 pairs of acrocentric autosomes. The X chromosome was a median acrocentric, between pairs 3 and 4 in size, and the Y chromosome was a small acrocentric (between pairs 19 and 20). Five pairs with nucleolus organizer regions were located at the short arms. C-banding showed blocks of constitutive heterochromatin occurring in the centromeres of all autosomes and of the X chromosome. The Y chromosome was entirely heterochromatic. In order to identify possible homologies, karyotypes of Kunsia and Scapteromys, the phyletically related taxa, were compared. No autosome shared by either genus was found by G-band comparisons. The C-band patterns and those produced by Alu I, Mbo I, Rsa I and Hae III restriction endonucleases were also different. The results of FISH indicated a different composition of the telomeric regions of the chromosomes of both taxa, since in Scapteromys the probes hybridized in both telomeres, and in Kunsia this hybridization only occurred in one of the telomeres. These differences also occurred in the localization and number of nucleolus organizer regions.


Assuntos
Genoma , Cariotipagem , Roedores/genética , Animais , Roedores/classificação
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