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1.
Acta cir. bras ; 33(5): 439-445, May 2018. graf
Artigo em Inglês | LILACS | ID: biblio-949344

RESUMO

Abstract Purpose: To investigate the effects of capsiate treatment on hepatic hyperplasia in partially hepatectomized rats. Methods: The animals were divided into a Capsiate group (CPH), a Capsiate Post-Partial Hepatectomy group (CPPH) and a Partial Hepatectomy Control group (PH). CPH and CPPH animals received 60 mg/kg/day Capsiate for 30 days. Next, the rats underwent partial hepatectomy. CPPH animals continued to receive treatment for 48 h after partial hepatectomy. Liver tissue and intracardiac blood samples were obtained 24 or 48 h after PH. Results: Capsiate treatment interfered with hepatic parameters, reducing the number of mitoses and apoptosis and increasing blood ALT and alkaline phosphatase concentrations. Conclusion: Capsiate treatment preceding hepatic surgery may compromise the initial period of postoperative recovery.


Assuntos
Animais , Masculino , Ratos , Capsaicina/análogos & derivados , Hepatectomia , Fígado/enzimologia , Aspartato Aminotransferases/metabolismo , Capsaicina/farmacologia , Ratos Wistar , Apoptose/efeitos dos fármacos , Alanina Transaminase/metabolismo , Fosfatase Alcalina/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Regeneração Hepática/efeitos dos fármacos , Mitose/efeitos dos fármacos
2.
Rev. Col. Bras. Cir ; 45(4): e1715, 2018. tab, graf
Artigo em Português | LILACS | ID: biblio-956577

RESUMO

RESUMO Objetivo: avaliar as características dos pacientes portadores de melanoma cutâneo atendidos no Hospital São Paulo - UNIFESP. Métodos: estudo retrospectivo de 184 casos de melanoma cutâneo. Foram analisadas as informações sobre sexo, idade, características do tumor, características histológicas e estadiamento. Resultados: a média de idade ao diagnóstico foi de 58,7 anos, com distribuição etária homogênea entre os sexos e predominância em indivíduos brancos (70,6%). Observou-se acometimento predominante de tronco, em homens (36,7%), e de membros inferiores, em mulheres (42%). A exposição solar, com queimaduras, foi mais comum entre homens (31,2%) do que entre mulheres (23,5%). Houve aumento de aproximadamente três vezes no acometimento linfonodal quando o índice mitótico subia de zero (11,9%) para uma ou mais mitoses por campo (36,2%), e aumento progressivo do acometimento linfonodal e de desfechos ruins quanto maior a espessura de Breslow: 10,2% quando menor do que 1mm e 59,2% quando maior do que 4mm. Conclusão: as características dos pacientes portadores de melanoma cutâneo atendidos no Hospital São Paulo são semelhantes às encontradas na literatura.


ABSTRACT Objective: to evaluate the characteristics of the patients with cutaneous melanoma treated at the São Paulo Hospital - UNIFESP. Methods: we conducted a retrospective study of 184 cases of cutaneous melanoma. We analyzed information on gender, age, tumor characteristics, histological characteristics and staging. Results: mean age at diagnosis was 58.7 years, with homogeneous age distribution between genders and predominance in white individuals (70.6%). There was a predominance of trunk involvement in men (36.7%) and lower limbs in women (42%). Sun exposure, with sunburns, was more common among males (31.2%) than among females (23.5%). There was an approximately three-fold increase in lymph node involvement when the mitotic index rose from zero (11.9%) to one or more mitosis per field (36.2%). In addition, the greater the Breslow thickness, the greater the lymph node involvement and poor the outcomes: 10.2% when less than 1mm and 59.2% when greater than 4mm. Conclusion: the characteristics of patients with cutaneous melanoma treated at Hospital São Paulo are similar to those found in the literature.


Assuntos
Humanos , Masculino , Feminino , Neoplasias Cutâneas/epidemiologia , Melanoma/epidemiologia , Queimadura Solar , Brasil/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Distribuição por Sexo , Distribuição por Idade , Linfonodos , Pessoa de Meia-Idade , Mitose
3.
Braz. j. med. biol. res ; 48(6): 493-501, 06/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-748227

RESUMO

Apolipoprotein E (APOE=gene, apoE=protein) is a known factor regulating the inflammatory response that may have regenerative effects during tissue recovery from injury. We investigated whether apoE deficiency reduces the healing effect of alanyl-glutamine (Ala-Gln) treatment, a recognized gut-trophic nutrient, during tissue recovery after 5-FU-induced intestinal mucositis. APOE-knockout (APOE-/-) and wild-type (APOE+/+) C57BL6J male and female mice (N=86) were given either Ala-Gln (100 mM) or phosphate buffered saline (PBS) by gavage 3 days before and 5 days after a 5-fluorouracil (5-FU) challenge (450 mg/kg, via intraperitoneal injection). Mouse body weight was monitored daily. The 5-FU cytotoxic effect was evaluated by leukometry. Intestinal villus height, villus/crypt ratio, and villin expression were monitored to assess recovery of the intestinal absorptive surface area. Crypt length, mitotic, apoptotic, and necrotic crypt indexes, and quantitative real-time PCR for insulin-like growth factor-1 (IGF-1) and B-cell lymphoma 2 (Bcl-2) intestinal mRNA transcripts were used to evaluate intestinal epithelial cell turnover. 5-FU challenge caused significant weight loss and leukopenia (P<0.001) in both mouse strains, which was not improved by Ala-Gln. Villus blunting, crypt hyperplasia, and reduced villus/crypt ratio (P<0.05) were found in all 5-FU-challenged mice but not in PBS controls. Ala-Gln improved villus/crypt ratio, crypt length and mitotic index in all challenged mice, compared with PBS controls. Ala-Gln improved villus height only in APOE-/- mice. Crypt cell apoptosis and necrotic scores were increased in all mice challenged by 5-FU, compared with untreated controls. Those scores were significantly lower in Ala-Gln-treated APOE+/+ mice than in controls. Bcl-2 and IGF-1 mRNA transcripts were reduced only in the APOE-/--challenged mice. Altogether our findings suggest APOE-independent Ala-Gln regenerative effects after 5-FU challenge.


Assuntos
Animais , Feminino , Masculino , Antimetabólitos Antineoplásicos/efeitos adversos , Apolipoproteínas E/deficiência , Dipeptídeos/farmacologia , Fluoruracila/efeitos adversos , Mucosa Intestinal/efeitos dos fármacos , Mucosite/tratamento farmacológico , Apoptose/efeitos dos fármacos , Peso Corporal , Dipeptídeos/uso terapêutico , Fator de Crescimento Insulin-Like I/análise , Mucosa Intestinal/patologia , Contagem de Leucócitos , Linfoma de Células B , Mitose/efeitos dos fármacos , Mucosite/induzido quimicamente , Mucosite/patologia , Distribuição Aleatória , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do Tratamento
4.
Acta cir. bras ; 29(9): 603-607, 09/2014. tab
Artigo em Inglês | LILACS | ID: lil-722129

RESUMO

PURPOSE: To compare controlled liver regeneration in rats submitted to 60% hepatic resection having L-arginine supplemented diet, based on weight changes of the regenerated liver, laboratory parameters of liver function and pathological findings. METHODS: Thirty-six rats were divided into two groups, control and L- arginine. The first received standard chow and saline solution by gavage. The second had supplementation with L- arginine. Animals were killed on postoperative period at 24h, 72h and seven days. For analysis of liver regeneration was used Kwon formula for weight, laboratory tests and mitosis. RESULTS: Weight, showed no benefit with L- arginine supplementation; however, intergroup comparison in the first 24h observed positive effect on supplementation (p=0.008). Alkaline phosphatase was increased in arginine group (p<0.04). The number of mitoses showed no difference between the two groups; however, in the first 24 hours, the supplemented group had higher number of mitoses within the groups (p=0.03). CONCLUSION: Supplementation with L-arginine did not show benefits in liver regeneration; however, supplemented group in the first 24 hours showed benefits over 72 hours and seven days of the evaluation by weight gain and number of mitosis. .


Assuntos
Animais , Masculino , Arginina/farmacologia , Suplementos Nutricionais , Regeneração Hepática/efeitos dos fármacos , Hepatectomia , Regeneração Hepática/fisiologia , Fígado/efeitos dos fármacos , Fígado/patologia , Fígado/fisiologia , Mitose/efeitos dos fármacos , Mitose/fisiologia , Tamanho do Órgão , Ratos Wistar , Fatores de Tempo
5.
Rev. biol. trop ; 62(2): 671-688, Jun.-Aug. 2014. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-715462

RESUMO

Mexico is a biodiverse country in several taxa as reptiles, that include several species of freshwater and marine turtles. Eventhough most of this group species are under protection, Tabasco State has nine native freshwater turtles, like Kinosternon leucostomum, Trachemys scripta and Staurotypus triporcatus that are very important in traditional dishes. This has resulted in a critical level of their populations, together with little biological knowledge for their conservation. Therefore, this study was dedicated to turtle cytogenetics. The study was conducted using the conventional methods for cytogenetics. The results showed the modal diploid and haploid number for K. leucostomum of 2n=56 (2n=56+3 microchromosomes “B”) and 1n=28 chromosomes in mitosis and meiosis, respectively. In T. scripta 2n=50 chromosomes (2n=50+2 microchromosomes “B”) and 1n=25 chromosomes were also characterized. Whereas in S. triporcatus we only report the 2=54 chromosomes (2n=54+2 microchromosomes “B”). The karyological formula for K. leucostomum was integrated by 12 metacentric-submetacentric chromosomes “msm”/”A”+22 subtelocentrictelocentric chromosomes “stt”/”B”+22 telocentric chromosomes “T”/”C” with fundamental number (FN) of 90 chromosome arms. While T. scripta karyotype was integrated by 32 “msm/”A”+10 “stt”/”B”+8”T/”C” chromosomes, with FN of 92 arms. S. triporcatus karyotype formula was built up by 20 chromosomes “msm”/”A”+34 chromosomes “T”/”C” with FN of 74. The variation in chromosome classification, the fundamental number and the presence of supernumerary microchromosomes “B” in the studied species, were evidence of a particular chromosome cytotypes in Tabasco. We considered that the presence of microchromosomes “B” probably has different origins, and they may be very important as a pattern for the formation or separation of new species. This study also showed the absence of heterologous chromosomes between the females and males karyotypes from the studied species. Rev. Biol. Trop. 62 (2): 671-688. Epub 2014 June 01.


México es un país biodiverso en varios grupos taxonómicos incluyendo a los reptiles, por ello en el país existen varias especies de tortugas dulceacuícolas y marinas. Las especies que integran dicho grupo se encuentran dentro del listado de especies sujetas a protección. El estado de Tabasco cuenta con nueve especies de tortugas de agua dulce, de las cuales Kinosternon leucostomum, Trachemys scripta y Staurotypus triporcatus son de las más importantes dentro de la tradición culinaria, hecho que las ha llevado a niveles críticos en sus poblaciones; aunado al poco conocimiento biológico que sobre dichas especies existe para conservarlas. Por lo anterior, el presente estudio de citogenética es el primero en tortugas de agua dulce en la región. El estudio se realizó, empleando el método convencional de citogenética. Los resultados muestran, el número modal diploide y haploide de K. leucostomum de 2n=56 (2n=56+3 microcromosomas “B”) y 1n=28 cromosomas 686 en mitosis y meiosis, respectivamente. En T. scripta de 2n=50 cromosomas (2n=50+2 microcromosomas “B”) y 1n=25 cromosomas. Mientras que en S. triporcatus solo se reporta el 2n=54 cromosomas (2n=54+2 microcromosomas “B”). La fórmula cromosómica en K. leucostomum, fue de 12 cromosomas metacéntricos submetacéntricos “msm”/“A”+22 cromosomas subtelocéntricos-telocéntricos “stt”/“B”+22 cromosomas telocéntricos “T”/“C”, con número fundamental (NF) de 90 brazos cromosómicos. En T. scripta fue de 32 cromosomas “msm”/“A”+10 cromosomas “stt”/“B”+8 cromosomas “T”/“C”, con NF de 92 y en S. triporcatus 20 cromosomas “msm”/“A”+34 cromosomas “T”/“C” con NF de 74. La variación en la clasificación cromosómica, el número fundamental y la presencia de microcromosomas “B” supernumerarios en las tres especies, son evidencia de citotipos cromosómicos particulares de las tortugas de Tabasco. Se argumenta que la presencia de los microcromosomas “B” tiene diferentes orígenes y de su importancia como pauta para la formación o separación de nuevas especies. En el estudio se descarta la presencia de cromosomas heterólogos entre las hembras y los machos de las especies estudiadas.


Assuntos
Animais , Feminino , Masculino , Cromossomos/genética , Tartarugas/genética , Cariotipagem , Meiose , México , Mitose , Tartarugas/classificação
6.
Arch. cardiol. Méx ; 84(2): 102-109, abr.-jun. 2014.
Artigo em Espanhol | LILACS | ID: lil-732014

RESUMO

La proliferación de los miocitos que forman parte de los ventrículos cardíacos del mamífero adulto ha sido descartada por algunos investigadores con el argumento de que estas células están diferenciadas en forma terminal; sin embargo, este dogma ha sido puesto en duda a partir de los hallazgos de otros investigadores quienes han observado que estos miocitos pueden presentar los procesos necesarios para la proliferación, es decir síntesis de ADN, mitosis y citocinesis, cuando el miocardio se daña en forma experimental con estrategias de tipo farmacológico o quirúrgico, o debido a condiciones patológicas relacionadas con el sistema cardiovascular. Esta revisión integra algunos de los trabajos disponibles en la literatura que han evaluado la síntesis del ADN, mitosis y citocinesis en estas células, en el miocardio dañado, para saber si su proliferación puede ser considerada como un fenómeno factible. La revisión concluye con una reflexión sobre las perspectivas del conocimiento generado en esta área de estudio.


Proliferation of adult mammalian ventricular cardiomyocytes has been ruled out by some researchers, who have argued that these cells are terminally differentiated; however, this dogma has been rejected because other researchers have reported that these cells can present the processes necessary to proliferate, that is, DNA synthesis, mitosis and cytokinesis when the heart is damaged experimentally through pharmacological and surgical strategies or due to pathological conditions concerning the cardiovascular system. This review integrates some of the available works in the literature evaluating the DNA synthesis, mitosis and cytokinesis in these myocytes, when the myocardium is damaged, with the purpose of knowing if their proliferation can be considered as a feasible phenomenon. The review is concluded with a reflection about the perspectives of the knowledge generated in this area.


Assuntos
Adulto , Animais , Cães , Humanos , Camundongos , Ratos , Proliferação de Células , DNA , Ventrículos do Coração/citologia , Mitose/fisiologia , Miócitos Cardíacos/fisiologia , Bromodesoxiuridina/metabolismo , Diferenciação Celular , Citocinese , Miócitos Cardíacos/citologia , Antígeno Nuclear de Célula em Proliferação/metabolismo , RNA Mensageiro/metabolismo
7.
Rev. MVZ Córdoba ; 18(3): 3868-3876, set.-dic. 2013. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-700573

RESUMO

Objetivo. Estudiar el ciclo celular y realizar la descripción cromosómica de Espeletiopsis muiska, utilizando células meristemáticas de ápices radicales obtenidos a través de cultivo in vitro de embriones en medio MS suplementado con AIB. Materiales y métodos. Se colectaron ápices radicales a diferentes horas del día y se contaron en ellos las células presentes en cada fase mitótica, se determinó la duración del ciclo celular y la hora de mayor actividad mitótica. La descripción de los cromosomas y la elaboración del cariotipo de la especie, se realizó utilizando un protocolo que permitió la obtención de cromosomas metafásicos. Resultados. Respecto a la duración del ciclo celular, se encontró que la interfase comprende el 94.65% y la mitosis el 5.35% del total del ciclo celular. Entre las fases mitóticas la profase tiene mayor duración, 1.92%, mientras que la anafase es la más corta, 0.96%. En cuanto a la hora mitótica, las células meristemáticas de los ápices radicales presentaron mayor actividad entre las 10:30 y las 11:15. Con el estudio citogenético se encontraron 19 pares de cromosomas con longitudes e índices centroméricos similares y cariotipo asimétrico. Conclusiones. El estudio detallado de los cromosomas, permitió determinar un complemento cromosómico 2n=38+2B, dos cromosomas con microsatélites terminales y uno con constricción secundaria.


Objective. The cell cycle and chromosomic description of Espeletiopsis muiska was studied in meristematic cells of root tips obtained from in vitro culture of embryos on MS medium supplemented with IBA. Materials and methods. Root tips at different times of day were collected and the cells in each mitotic phase were counted. With this information, the cell cycle length and mitotic activity was determined at its peak hours. Description of chromosomes and elaboration of karyotype of the specie was done with a protocol that allows obtaining metaphase chromosomes. Results. Regarding the cell cycle length, we found that the interface includes the 94.65% and mitosis the 5.35% of total cell cycle. Regarding the mitotic phases, the prophase lasts longer, 1.92%, while the anaphase is the shortest, 0.96%. As to mitotic hour, meristematic cells of root tips showed an increased activity between 10:30 and 11:15. 19 pairs of chromosomes with similar lengths, similar centromeric indices and asymmetrical karyotype were found in this cytogenetic study. Conclusions. The detailed study of the chromosomes revealed a chromosome complement 2n=38+2B, two chromosomes with microsatellite terminals and one with a secondary constriction.


Assuntos
Animais , Cromossomos , Mitose
8.
Acta cir. bras ; 27(6): 361-369, June 2012. ilus
Artigo em Inglês | LILACS | ID: lil-626253

RESUMO

PURPOSE: To analyse histopathological alterations characterized by the mitotic index in the mucosa of the large intestine in Wistar rats submitted to jejunoileal bypass operation after continued administration of sodium nitrite and vitamin C to different groups. METHODS: Eighty male Wistar rats were employed and separated into 12 groups. In the control group (20 rats): five animals ingested only water; five animals received vitamin C; five animals received sodium nitrite and five received sodium nitrite + vitamin C. In the sham group (20 rats), the animals were anesthetized and underwent midline laparotomy and only intestinal manipulation was performed: five animals ingested only water; five animals received vitamin C; five animals received sodium nitrite and five received sodium nitrite + vitamin C. In the operated group 40 rats underwent a jejunoileal bypass surgery: ten animals ingested only water; ten animals received vitamin C; ten animals received sodium nitrite and ten received sodium nitrite + vitamin C. The mean weight of the animals was measured weekly. The large intestine was subdivided into cecum (S1), ascending colon (S2), transverse colon (S3), descending colon (S4) and rectum (S5) for histopathological analysis and mitotic counts. The statistical analysis was used to compare the mitotic indices. The level of significance was 5%. RESULTS: The mean of all the segments indicates that the sodium nitrite+vitamin C group obtained the lowest mitotic index compared to the other treatments in the control group. The segments S1 and S2 showed a statistical difference with the vitamin C treatment: a higher mitotic index and better preservation of the mucosa in the operated group. In the sham group the main statistical difference occurred only in the sodium nitrite+vitamin C group between the means of the segments. CONCLUSIONS: The comparison of all the colonic segments of the various groups revealed a lower mitotic index in the animals treated with sodium nitrite+vitamin C. In addition, it was found that vitamin C did not present a statistically significant inhibiting effect on the preservation of the mucosa and the mitotic index.


OBJETIVO: Analisar as alterações histopatológicas caracterizada pelo índice mitótico na mucosa do intestino grosso em ratos Wistar submetidos a operação de bypass jejunoileal após a administração continuada de nitrito de sódio e vitamina C para diferentes grupos. MÉTODOS: Oitenta ratos Wistar foram utilizados e separados em 12 grupos. No grupo controle (20 ratos): cinco animais ingeriram apenas água; cinco animais receberam vitamina C, cinco animais receberam nitrito de sódio e cinco receberam nitrito de sódio + vitamina C. No grupo sham (20 ratos), os animais foram anestesiados e submetidos a laparotomia mediana e só a manipulação intestinal foi realizada: cinco animais ingeriram apenas água; cinco animais receberam vitamina C, cinco animais receberam nitrito de sódio e cinco receberam nitrito de sódio + vitamina C. No grupo operado 40 ratos foram submetidos a uma cirurgia de bypass jejunoileal: dez animais ingeridos apenas água; dez animais receberam vitamina C, dez animais receberam nitrito de sódio e dez nitrito de sódio + vitamina C. O peso médio dos animais foi medido semanalmente. O intestino grosso foi subdividido em ceco (S1), cólon ascendente (S2), cólon transverso (S3), cólon descendente (S4) e reto (S5) para análise histopatológica e contagem das mitoses. A análise estatística foi utilizado para comparar os índices mitóticos. O nível de significância foi de 5%. RESULTADOS: A média de todos os segmentos indica que o grupo que ingeriu nitrito de sódio + vitamina C obteve o menor índice mitótico em relação aos demais tratamentos no grupo controle. Os segmentos S1 e S2 mostraram uma diferença estatística com a vitamina C de tratamento: um maior índice mitótico e melhor preservação da mucosa no grupo operado. No grupo sham a principal diferença estatística ocorreu apenas no grupo que ingeriu nitrito de sódio + vitamina C entre as médias dos segmentos. CONCLUSÕES: A comparação de todos os segmentos do colon dos vários grupos revelaram um menor índice de mitose nos animais tratados com nitrito de sódio + vitamina C. Além disso, a vitamina C não apresentou efeito inibidor, estatísticamente significativo, na preservação da mucosa e do índice de mitoses.


Assuntos
Animais , Masculino , Ratos , Ácido Ascórbico/farmacologia , Conservantes de Alimentos/farmacologia , Intestino Grosso/patologia , Derivação Jejunoileal/efeitos adversos , Mitose/efeitos dos fármacos , Nitrito de Sódio/farmacologia , Antioxidantes/farmacologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Intestino Grosso/efeitos dos fármacos , Índice Mitótico , Mitose/fisiologia , Ratos Wistar
9.
An. bras. dermatol ; 86(4,supl.1): 107-109, jul,-ago. 2011. ilus
Artigo em Português | LILACS | ID: lil-604135

RESUMO

Paciente, sexo feminino, 23 anos, com melanoma extensivo superficial em dorso, Breslow 0,35 mm, Clark II, sem ulcerações e com 2 mitoses / mm². Foi submetida à ampliação de margem e biópsia de dois linfonodos sentinela (axila esquerda). O exame anatomopatológico mostrou micrometástases, no seio subcapsular de ambos. Seguindo a recomendação do "American Joint Commitee on Cancer" 2009, a paciente foi submetida à linfadenectomia axilar total, sem outros linfonodos metastáticos. A aplicação da dermatoscopia vem permitindo maior precisão diagnóstica de melanoma cutâneo, contribuindo para maior proporção de melanoma fino ao diagnóstico. A taxa mitótica foi incluída como um importante fator prognóstico para melanomas finos pelo "American Joint Commitee on Cancer" 2009, sugerindo biópsia para esses pacientes.


23-year-old female patient, with superficial spreading melanoma (SSM) on the back, Breslow 0.35 mm, Clark II, without ulceration and with 2 mitosis/mm². Patient was submitted to margin enlargement and sentinel biopsy of 2 lymph nodes (left armpit). Histopathology revealed micrometastasis in the subcapsular sinus of both. Following the recommendation of the 2009 American Joint Committee on Cancer Melanoma Staging (AJCC), the patient underwent complete axillary lymphadenectomy. No other lymph nodes were metastatic. The clinical application of dermoscopy has enabled more accurate diagnosis of cutaneous melanoma, probably contributing to a greater proportion of thin melanomas at diagnosis. The mitotic rate was included as an important prognostic factor for thin melanomas by the AJCC, suggesting biopsy for these patients.


Assuntos
Feminino , Humanos , Adulto Jovem , Mitose , Melanoma/patologia , Biópsia de Linfonodo Sentinela , Neoplasias Cutâneas/patologia , Excisão de Linfonodo , Valor Preditivo dos Testes , Prognóstico
11.
An. acad. bras. ciênc ; 83(2): 627-635, June 2011. ilus
Artigo em Inglês | LILACS | ID: lil-589919

RESUMO

Polo-like kinases are important regulators of cell cycle progression and mitosis. They constitute a family of conserved serine/threonine kinases which are highly related in their catalytic domains and contain polo boxes involved in protein-protein interactions and subcellular localization. In mammals, five Plks (Plk 1-5) encompass diverse roles in centrosome dynamics, spindle formation, intra S-phase and G2/M checkpoints and DNA damage response. Plk1 is a key positive regulator of mitosis and is overexpressed in various types of cancers. Plk4 is a divergent member of the Plk family, with essential functions in centriole duplication. Homozygous disruption of Plk1 or Plk4 in mice is lethal in embryos. Two Plk members SmPlk1 and SmSak, homologous to Plk1 and Plk4 respectively, are present in the parasitic platyhelminth Schistosoma mansoni. Structural and functional analyses of SmPlk1 have demonstrated its conserved function in the regulation of cell cycle G2/M transition in Xenopus oocytes. The anti-cancer drug BI 2536 (the most potent and selective Plk1 inhibitor) inhibits specifically the catalytic activity of SmPlk1 and induced profound alterations in schistosome gonads, indicating a role of SmPlk1 in parasite gametogenesis and its potential as a novel chemotherapeutic target against schistosomiasis. Functions of SmSak in cell cycle regulation and schistosome gonad development are currently investigated.


Quinases do tipo Polo ("polo-like") são importantes reguladores da progressão do ciclo celular e da mitose. Elas constituem uma família de serina/treonina quinases que são altamente relacionadas entre si no seu domínio catalítico e contêm blocos "polo" envolvidos com interações proteína-proteína e com localização subcelular. Em mamíferos, cinco Plks (Plk 1-5) englobam diversos papéis na dinâmica do centrossomo, formação do fuso, "checkpoints" dentro da fase S e da transição G2/M, e na resposta aos danos do DNA. Plk1 é um regulador positivo chave da mitose, e é superexpresso em vários tipos de câncer. Plk4 é um membro divergente da família Plk, com funções essenciais na duplicação do centríolo. Deleção homozigótica de Plk1 ou Plk4 em camundongos é letal em embriões. Dois membros da família Plk, SmPlk1 e SmSak, homólogos a Plk1 e Plk4, respectivamente, estão presentes no parasita platelmíntico Schistosoma mansoni. Análises estruturais e funcionais de SmPlk1 demonstraram uma função conservada na regulação da transição G2/M do ciclo celular em ovócitos de Xenopus. A droga anticâncer BI2536 (o inibidor mais potente e seletivo de Plk1) inibe específicamente a atividade catalítica de SmPlk1 e induz alterações profundas nas gonadas de esquistossomos, indicando um papel de SmPlk1 na gametogênese do parasita e seu potencial como um alvo terapêutico novo contra a esquistossomose. As funções de SmSak na regulação do ciclo celular e no desenvolvimento das gônadas de esquistossomos estão sendo investigadas no momento.


Assuntos
Animais , Gônadas/enzimologia , Mitose , Proteínas Serina-Treonina Quinases/fisiologia , Schistosoma mansoni/enzimologia , Reprodução , Schistosoma mansoni/fisiologia , Xenopus
12.
Rev. biol. trop ; 59(2): 683-692, jun. 2011. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-638112

RESUMO

Karyotypic characterization in mitosis and meiosis of the common snook Centropomus undecimalis (Pisces: Centropomidae). The common snook Centropomus undecimalis inhabits marine, brackish and freshwater habitats in the Western Central Atlantic Ocean, including the Gulf of Mexico. Common snook is an economically important fish in many localities, nevertheless the number of studies on its biology and genetics are still few. The present study attempts to establish the cytogenetic profiles of the specimens collected in Paraiso Municipality Tabasco, Mexico. Tissue of five females and eight male organisms were processed by conventional cytological techniques to obtain chromosome slides of high quality in order to assemble the karyotype. The results from the kidney tissue analysis showed that 85.1% of 288 mitosis had a 2n=48 chromosomes, and 52.8% of 104 meiosis exhibited the haploid number 1n=24. The diploid karyotype showed 48 monoarmed chromosomes of the telocentric (T) type. There was no chromosome heteromorphism between females and males. The diploid karyotype was very similar to that observed in the majority of marine fishes. Rev. Biol. Trop. 59 (2): 683-692. Epub 2011 June 01.


El robalo blanco Centropomus undecimalis, vive en hábitats marinos, salobres y dulceacuícolas en el océano Atlántico occidental, incluyendo el golfo de México. La especie, es económicamente importante en varias localidades, no obstante los estudios sobre su biología y genética son hasta el momento pocos. El presente estudio tiene como propósito, la caracterización citogenética de especímenes recolectados en el municipio de Paraíso, Tabasco, México. Cinco hembras y ocho machos fueron procesados por técnicas citológicas convencionales para la obtención de preparaciones cromosómicas de buena calidad para elaborar el cariotipo. Los resultados del análisis del tejido del riñón, mostraron que 85.1% de 288 mitosis tienen 2n=48 cromosomas y 52.8% de 104 meiosis exhiben el número haploide de 1n=24. El cariotipo diploide mostro 48 cromosomas monorrámeos de tipo telocéntrico (T). No se observó heteromorfismo cromosómico entre hembras y machos. El cariotipo diploide fue similar a los observados en la mayoría de peces marinos.


Assuntos
Animais , Feminino , Masculino , Peixes/genética , Meiose/genética , Mitose/genética , Oceano Atlântico , Peixes/classificação , Peixes/fisiologia , Cariotipagem , Meiose/fisiologia , Mitose/fisiologia
13.
Braz. j. biol ; 71(2): 487-490, maio 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-592585

RESUMO

Treatment of human breast epithelial cells MCF-10F with 17-β-estradiol has been reported to result in E2-transformed cells which have given rise to highly invasive C5 cells that in turn generate tumors in SCID mice. From these tumors, various cell lines, among which C5-A6-T6 and C5-A8-T8, were obtained. Although different phases of the tumorigenesis process in this model have been studied in molecular biology and image analysis assays, no cytological data on apoptotic ratios and mitotic abnormalities have been established to accompany the various steps leading to 17-β-estradiol-treated MCF-10F cells to tumorigenesis. Here we detected that the apoptotic ratio decreases with the transformation and tumorigenesis progress, except for the tumor cell line C5-A8-T8, probably on account of its more intense proliferation rate and a more rapid culture medium consumption. Increased frequency of mitotic abnormalities contributed by triple- and tetrapolar metaphases, and by lagging chromosomes and chromosome bridges observed at the anaphase found by transformation and tumorigenesis progress. However, no difference was found under these terms when the C5-A6-T6 and C5-A8-T8 tumor cell lines were compared to each other. Present findings are in agreement with the nuclear instability and enrichment of dysregulated genes in the apoptotic process promoted by transformation and tumorigenesis in 17-β-estradiol-treated MCF-10F cells.


O tratamento das células epiteliais mamárias humanas MCF-10F com 17-β-estradiol tem sido relatado como resultando nas células transformadas E2, que deram origem às células C5, altamente invasivas, e que geraram tumores em camundongos SCID. A partir desses tumores foram originadas em cultura células tumorais, dentre as quais C5-A6-T6 e C5-A8-T8. Embora diversas fases do processo tumorigênico neste modelo tenham sido estudadas por ensaios de biologia molecular e análise de imagem, não foram ainda estimados dados citológicos referentes a índices apoptóticos e anomalias mitóticas que acompanhassem os vários passos que levam as células CF-10F tratadas com 17-β-estradiol à tumorigênese. Neste trabalho detectamos que o índice apoptótico decresce com a transformação e o avanço da tumorigênese, exceto na linhagem celular tumoral C5-A8-T8, provavelmente por causa de sua velocidade de proliferação mais intensa, que poderia levá-la a um consumo mais rápido do meio de cultura presente e à morte celular. Um aumento na frequência de anomalias mitóticas contribuídas por metáfases tripolares e tetrapolares e por pontes cromossômicas e cromossomos desgarrados, identificáveis na anáfase, foi observado com a transformação e o progresso da tumorigênese. Contudo não foram detectadas diferenças nesses parâmetros quando se compararam as linhagens tumorais C5-A6-T6 e C5-A8-T8 entre si. Os presentes achados estão de acordo com a instabilidade nuclear e o enriquecimento em desregulação de genes que atuam no processo apoptótico, promovidos pela transformação e tumorigênese nas células MCF-10F tratadas com 17-β-estradiol.


Assuntos
Animais , Feminino , Humanos , Camundongos , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Estradiol/farmacologia , Mitose/efeitos dos fármacos , Linhagem Celular Transformada , Linhagem Celular Tumoral , Transformação Celular Neoplásica
15.
Biocell ; 34(3): 95-101, Dec. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-595010

RESUMO

Mikania glomerata is a plant used in Brazilian traditional medicine, known as 'guaco'. It possesses anti-inflammatory properties and the aqueous extracts of its leaves are indicated for the treatment of diseases of the respiratory tract. This study aimed at evaluating the antiproliferative and genotoxic effect of Mikania glomerata leaf infusions on the cell cycle of onion. The material used was collected in the native environment from Rio Grande do Sul State, Brazil. Aqueous extracts through infusions were prepared in two concentrations: 4g/L (usual concentration) and 16g/L (4x more concentrated) of each of the populations. Two groups of four onion bulbs for each plant population were used plus a control group. The rootlets were fixed in ethanol-acetic acid (3:1), conserved in ethanol 70% and slides were prepared using the squashing technique colored with orcein 2%. The cells were observed and analyzed during cell cycle. Per group of bulbs, 2000 cells were analyzed, and the mean values of the cell number of each of the phases of the cell cycle were calculated, determining the mitotic index (MI). Statistic analyses of the data were carried out by the x2 ( p= 0.05) test. We conclude that M. glomerata presents both antiproliferative and genotoxic activity.


Assuntos
Anti-Inflamatórios/toxicidade , Ciclo Celular , Citotoxinas/toxicidade , Mikania/química , Raízes de Plantas/citologia , Raízes de Plantas , Brasil , Cebolas/citologia , Cebolas , Extratos Vegetais/toxicidade , Medicina Tradicional , Mitose , Mutagênicos/toxicidade
16.
Biocell ; 33(3): 149-154, Dec. 2009. ilus, graf
Artigo em Inglês | LILACS | ID: lil-595019

RESUMO

Triatoma infestans, a blood-feeding insect, synchronises physiological mechanisms leading to moult with food intake. Since the corpora allata are important in moult and metamorphosis regulation, we have studied morphological changes in 4th instar nymphs (gland size, cell density, percent of animals showing mitoses and cell size). Changes were correlated with the effect of precocene II, epidermal proliferation, and with the extent of the [quot ]head critical period[quot ]. Based on morphological grounds, three stages can be defined in the gland along the 4th instar: Stage 1 (days 0-2 after feeding) showed small corpora allata, composed by a small number of cells, and in which mitoses were absent; Stage 2 (days 3-9) showed growing corpora allata, in which cell number was increasing and proliferation was apparent; and Stage 3 (days 10-13) showed no mitotic activity, and a sharply diminishing size of the gland, as a consequence of the diminishing size of their cells. The ability of precocene II to induce abnormal moulting disappeared during stage 2 correlating with the termination of the head critical period and suggesting that corpora allata are essential during days 3 to 5 to determine normal growth. Epidermal cell number was increasing as a consequence of more frequent mitotic activity, beginning after the finalization of the head critical period and after a first increment in the size of the gland.


Assuntos
Animais , Benzopiranos/farmacologia , Benzopiranos/metabolismo , Corpora Allata/citologia , Corpora Allata/crescimento & desenvolvimento , Corpora Allata , Doença de Chagas/transmissão , Proliferação de Células , Epiderme/crescimento & desenvolvimento , Epiderme , Insetos Vetores/crescimento & desenvolvimento , Insetos Vetores , Mitose , Mitose/fisiologia , Triatoma/crescimento & desenvolvimento , Triatoma
17.
Biocell ; 33(1): 25-32, Apr. 2009. ilus, tab
Artigo em Inglês | LILACS | ID: lil-595026

RESUMO

Different copper concentrations, as well as different exposure times, were applied to investigate both cytogenetical and ultrastructural alterations in garlic (Allium sativum L.) meristem cells. Results showed that the mitotic index decreased progressively when either copper concentration or exposure time increased. C-mitosis, anaphase bridges, chromosome stickiness and broken nuclei were observed in the copper treated root tip cells. Some particulates containing the argyrophilic NOR-associated proteins were distributed in the nucleus of the root-tip cells and the amount of this particulate material progressively increased with increasing exposure time. Finally, the nucleolar material was extruded from the nucleus into the cytoplasm. Also, increased dictyosome vesicles in number, formation of cytoplasmic vesicles containing electron dense granules, altered mitochondrial shape, disruption of nuclear membranes, condensation of chromatin material, disintegration of organelles were observed. The mechanisms of detoxification and tolerance of copper are briefly discussed.


Assuntos
Aberrações Cromossômicas/classificação , Allium , Allium/genética , Cobre/toxicidade , Meristema , Meristema/genética , Raízes de Plantas , Raízes de Plantas/genética , Citoplasma , Citoplasma/ultraestrutura , Mitose , Mitose/genética , Núcleo Celular , Núcleo Celular/ultraestrutura , Nucléolo Celular , Nucléolo Celular/ultraestrutura
18.
Acta cir. bras ; 24(1): 3-6, Jan.-Feb. 2009. graf, tab
Artigo em Inglês | LILACS | ID: lil-503097

RESUMO

PURPOSE: To recognize the regenerative capacity influenced by the administrating of estradiol. METHODS: 42 female Wistar rats were used, divided into two groups, the control and the experiment group. A resection of approximately 70 percent of the liver was made in the liver of these animals. The control group received an intramuscular injection of one ml of peanut oil. The experiment group were given estradiol hexahydrobenzoate (50µg) diluted in one ml of peanut oil. Calibrations were done after 36 hours and 7 days, using three methods: the formula of Kwon et al.21, to recognize gain in volume, counting of the mitosis figures in five fields and the percentage of positive PCNA nuclei. RESULTS: Gain in volume (mass) was similar in both groups after 36 hours (p=0.1873) and higher in the experiment groups after seven days (p=0.0447). Microscopy showed a similar number of mitosis figures after 36 hours (p=0.3528) and a tendency to be higher in the experiment group after 7 days (p=0.0883). The average of positive PCNA nuclei was higher in the experiment group both after 36 hours (p=0.0009) and 7 days (p=0.0000). CONCLUSION: The estradiol hexahydrobenzoate improved liver regeneration in rats submitted to a 70 percent hepatectomy.


OBJETIVO: Reconhecer a capacidade regenerativa influenciada pela administração de estradiol. MÉTODOS: Utilizaram-se 42 ratos Wistar, fêmeas, divididos em dois grupos controle e experimento. Realizou-se a ressecção de, aproximadamente, 70 por cento do fígado destes animais. Ratos do grupo controle receberam injeção intramuscular de um mililitro de óleo de amendoim, enquanto que os do grupo experimento receberam hexaidrobenzoato de estradiol (50µg) diluídos em um mililitro de óleo de amendoim. Fizeram-se as aferições com 36 horas e 7 dias, com 3 métodos: Fórmula de Kwon et al.21 para reconhecer ganho de volume, contagem das figuras de mitose existentes em 5 campos e percentual dos núcleos PCNA positivos em 5 campos. RESULTADOS: O ganho de volume (massa) foi semelhante nos dois grupos com 36 horas (p=0,1873) e maior no grupo experimento com 7 dias (p=0,0447). À microscopia observou-se número de figuras de mitose em número semelhante com 36 horas (p=0,3528) e tendência a ser maior no grupo experimento com 7 dias (p=0,0883). A média de núcleos PCNA positivos foi maior no grupo experimento tanto com 36 horas (p=0,0009) quanto com 7 dias (p=0,0000). CONCLUSÃO: O hexaidrobenzoato de estradiol favoreceu a regeneração hepática em ratos submetidos à hepatectomia 70 por cento.


Assuntos
Animais , Feminino , Ratos , Estradiol/análogos & derivados , Estrogênios/farmacologia , Hepatectomia , Regeneração Hepática/efeitos dos fármacos , Modelos Animais de Doenças , DNA , Avaliação Pré-Clínica de Medicamentos , Estradiol/farmacologia , Regeneração Hepática/imunologia , Mitose , Antígeno Nuclear de Célula em Proliferação/análise , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos Wistar
19.
Int. j. morphol ; 26(4): 995-1004, Dec. 2008. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-532944

RESUMO

El conejo ha demostrado ser un excelente modelo de estudio de implantación. Como ovulador obligado, el tiempo de preñez se puede establecer en forma precisa. La observación morfológica de cortes de úteros de 7, 8, 9 y 10 días pos coito, permitió en este estudio reconstruir una secuencia de los eventos morfométricos que ocurren durante la implantación, en el conejo. Se utilizaron 20 conejas neozelandesas blancas adultas (Oryctolagus cuniculus), nulíparas, no gestantes. Para la cruza, se utilizaron 5 machos de probada fertilidad. Los conejos fueron obtenidos del Bioterio de la Facultad de Medicina de la Universidad de La Frontera, Temuco, Chile. Determinamos como día 0, el momento del coito, sacrificando las hembras los días 7, 8, 9 y 10 de cada cruza. Una vez sacrificados, se disecó macro y mesoscópicamente la región pélvica, seleccionándose vesículas uterinas para sus estudios histológico e inmunocitoquímico. Se realizaron estudios morfométricos y de cinética celular con las técnicas de Túnel y PCNA. Se efectuó estadística descriptiva en base a promedio y desviación estándar (p< 0.001), utilizando el programa estadístico Stata 9.0. Las mediciones morfométricas obtenidas fueron de diámetro y volumen de la vesícula uterina, altura de la pared uterina y lumen glandular de regiones mesometrial y antimesometrial, para los días 7 al 10 post coito. Los análisis inmunocitoquímicos permitieron determinar: índice apoptótico de los núcleos celulares y el índice celular mitótico. Para el día 8 post coito se observaron los cambios morfométricos más significativos a nivel del lumen vesicular, altura de pared uterina de la región mesometrial, y lumen glandular. El mismo día se observaron cambios importantes en los índices celular mitótico y apoptótico. El conejo podría ser una especie usada para predecir el normal desarrollo embrionario, tras la comprensión morfológica y morfométrica de la implantación. Presenta una forma poco invasiva de implantación...


The rabbit has demonstrated to be an outstanding implanting model. As an obligated ovulating animal, its pregnancy time can be established exactly. The morphologic observation of uterus cuts of 7, 8, 9 and 10 days post mating, allowed this research to rebutid an apparent sequence morphometric events, that take place during rabbit implantation. Twenty New Zealand, white, adult, female rabbits were used in this research. (Oryctolagus cunículus), nulipara. And 4, proven, fertile, males were used for mating. These males were obtained from the Bioterio of the Faculty of Medicine at the Universidad de La Frontera, Temuco, Chile. Mating day was defined as day cero, sacrificing the females days 7, 8, 9 and 10 in each mating. Once sacrificed, the pelvic region was macro and mesoscopically dissected, and the vesicles were selected for histological and immunocitochemical study. Histological studies were performed with H.E. technique; morphometric and cellular kinetics with Tunnel and PCNA techniques. Descriptive statistics was used based on an average and standard deviation (p< 0.001). The Stata 9.0 statistical program was used. The morphometric measurements obtained were: diameters and volume of the uterine vesicle, height of the uterine wall and glandular lumen of the mesometrial and antimesometrial regions to 7-10 days post coitus. The immunocitochemical analysis identified: apoptotic Index of the cellular nucleous and cellular mitotic Índex. By day 8 post coitus were observed significant morphometric changes at the vesicular lumen, height of the uterine wall of the mesometrial region and glandular lumen. For the same day important changes of the cellular mitotic Índex and apoptotic Index were observed. The rabbit could be a species used to predict normal embryo development, after the morphologic comprehension of the implantation, given its not so invasive form of implantation and its capacity of early placenta formation. Providing updated information...


Assuntos
Animais , Feminino , Coelhos , Coelhos/anatomia & histologia , Coelhos/fisiologia , Implantação do Embrião/fisiologia , Útero/anatomia & histologia , Útero/fisiologia , Apoptose/fisiologia , Desenvolvimento Embrionário/fisiologia , Mitose/fisiologia , Fatores de Tempo , Útero/citologia
20.
J. appl. oral sci ; 16(6): 414-419, Nov.-Dec. 2008. ilus, tab
Artigo em Inglês | LILACS | ID: lil-499891

RESUMO

Actinic cheilitis is a potentially malignant lip lesion caused by excessive and prolonged exposure to ultraviolet radiation, which can lead to histomorphological alterations indicative of abnormal cell differentiation. In this pathology, varying degrees of epithelial dysplasia may be found. There are few published studies regarding the p53 and MDM2 proteins in actinic cheilitis. Fifty-eight cases diagnosed with actinic cheilitis were histologically evaluated using Banóczy and Csiba (1976) parameters, and were subjected to immunohistochemical analysis using the streptavidin-biotin method in order to assess p53 and MDM2 protein expression. All studied cases expressed p53 proteins in basal and suprabasal layers. In the basal layer, the nuclei testing positive for p53 were stained intensely, while in the suprabasal layer, cells with slightly stained nuclei were predominant. All cases also tested positive for the MDM2 protein, but with varying degrees of nuclear expression and a predominance of slightly stained cells. A statistically significant correlation between the percentage of p53 and MDM2-positive cells was established, regardless of the degree of epithelial dysplasia. The expression of p53 and MDM2 proteins in actinic cheilitis can be an important indicator in lip carcinogenesis, regardless of the degree of epithelial dysplasia.


Assuntos
Humanos , Queilite/patologia , /análise , /análise , Biomarcadores/análise , Adesão Celular/genética , Diferenciação Celular/genética , Nucléolo Celular/ultraestrutura , Núcleo Celular/ultraestrutura , Polaridade Celular/genética , Queilite/genética , Cromatina/ultraestrutura , Citoplasma/ultraestrutura , Células Epiteliais/patologia , Epitélio/patologia , Hiperplasia , Imuno-Histoquímica , Queratinas , Lábio/patologia , Mitose/genética , Luz Solar/efeitos adversos
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