Expression of ADAMTS13 and PCNA in the placentas of gestational diabetic mothers / Expresión de ADAMTS13 y PCNA en las placentas de madres diabéticas gestacionales

SUMMARY: GDM is linked with overexpression of inflammatory cytokines and increased oxidative stress, leading to endothelial dysfunction and vascular disorder. Weaimed to examine the expression of ADAMTS13 and PCNA in the placentas of gestational diabetes mellitus (GDM) patients to investigate the effects of hypoxia, induced by GDM, on proliferation and extracellular matrix formation in the maternal and fetal placenta cells. A total of 60 placentas were collected from pregnant women admitted to the obstetrics clinic. Thirty of them were diagnosed with GDM, and 30 of them were diagnosed with non-GDM patients. Samples were fixed in 10 % formaldehyde, after routine follow-up, embedded in paraffin wax. Sections of 5 µm were cut stained with Mayer Hematoxylin-Eosin, examined under a light microscope. Sections for immunohistochemical analysis were cut and processed for antigen retrievalin citrate solution. Sections were incubated with ADAMTS13 and PCNA primary antibodies, counterstained with hematoxylin, and evaluate under a light microscope. In histopathological examination, the non-diabetic placentas showed that decidua cells in the maternal region were polygonal with oval nuclei and organized in groups. In the GDM group, there were pyknosis and apoptotic changes in decidua cell nuclei. Vacuolar areas were observed in large cavities in maternal connective tissue. Inflammation and dilatation with congestion were observed in the blood vessels of the villus. In the GDM group, positive ADAMTS13 expression was observed in the decidua cells vascular endothelial cells, and surrounding connective tissue fibroblast cells. In the GDM group, a significant increase in PCNA expression was observed in decidua cells, connective tissue cells and endothelial cells. Functional changes in ADAMTS13 proteases and PCNA were thought to induce maternal and fetal complications by stimulating extracellular matrix development.

RESUMEN: La diabetes gestacional está relacionada con la sobreexpresión de citocinas inflamatorias y aumento del estrés oxidativo, lo que lleva a una disfunción endotelial y un trastorno vascular. Nuestro objetivo fue examinar la expresión de ADAMTS13 y PCNA en las placentas con diabetes mellitus gestacional (DMG) para investigar los efectos de la hipoxia inducida por DMG sobre la proliferación y formación de matriz extracelular en células placentarias maternas y fetales. Se recolectaron un total de 60 placentas de mujeres embarazadas ingresadas a la consulta de obstetricia. Treinta de ellas fueron diagnosticadas con DMG y 30 diagnosticadas sin DMG. Las muestras se fijaron en formaldehído al 10 %, y luego de un seguimiento de rutina, fueron embebidas en parafina. Se cortaron secciones de 5 µm teñidas con hematoxilina-eosina de Mayer, las que fueron examinadas bajo un microscopio óptico. Se cortaron y procesaron las secciones para el análisis inmunohistoquímico para la recuperación de antígeno en solución de citrato. Las secciones se incubaron con anticuerpos primarios ADAMTS13 y PCNA, se contratiñeron con hematoxilina y se evalua- ron con un microscopio óptico. En el examen histopatológico, las placentas no diabéticas mostraron que las células de la decidua en la región materna eran poligonales con núcleos ovalados y organizadas en grupos. En el grupo de DMG, se observó picnosis y cambios apoptóticos en los núcleos de las células de la decidua. Se observaron áreas vacuolares en el tejido conectivo materno. En los vasos sanguíneos de las vellosidades se observó inflamación y dilatación con congestión. En el grupo de DMG, se observó expresión positiva de ADAMTS13 en las células de la decidua, en las células endoteliales vasculares y en los fibroblastos del tejido conectivo circundante. En el grupo de DMG se observó un aumento significativo de la expresión de PCNA en células de la decidua, células de tejido conectivo y en las células endoteliales. Se considera que los cambios funcionales en las proteasas ADAMTS13 y PCNA inducen a complicaciones maternas y fetales al estimular el desarrollo de la matriz extracelular.

Improved histoarchitectural changes with angiotensin receptor blockers in early testicular and cauda toxicity in rats / Mejora de los cambios en la histoarquitectura con bloqueadores de receptores de angiotensina en la toxicidad precoz testicular y de cauda en ratas

SUMMARY: Reproductive dysfunction is a complication for many diseases and toxins. Its early diagnosis and treatment are immensely important. Here the morphological histoarchitecture changes in early testicular and cauda toxicity before and after treatment with angiotensin receptor blockers were evaluated. Low-grade testicular damage was induced using thioacetamide (TAA, 50 mg/kg/day) intraperitoneally for two weeks in rats. The rats were randomly divided into four groups (n = 8) treated daily orally for three weeks as follows: Normal control (distilled water), TAA (positive control), TAA+candesartan (0.2 mg/kg) and TAA+losartan (7.5 mg/kg). Serum testosterone and testicular malondialdehyde and glutathione were measured. The changes in histoarchitecture of testis and cauda epididymis were evaluated by hematoxylin and eosin for general structure, Masson's trichrome for collagen, periodic acid Schiff for basement membrane, and caspase-3 and proliferating cell nuclear antigen (PCNA) for immunohistochemical analysis. The TAA-rats showed decreases of serum testosterone and testicular glutathione, increases in testicular malondialdehyde, degenerative changes and apoptosis in germ cells, thickening of tubular basal lamina and increases in expression of caspase 3, and decreases in expression of PCNA. The ARBs (candesartan and losartan) significantly reversed these changes with non-significant differences in-between. Treatment with ARBs (candesartan and losartan) significantly reversed TAA-induced low-grade testicular and cauda toxicity in rats. This could be potentially useful for early treatment of male patients with occupational toxicant-induced reproductive dysfunction especially if they are using ARBs for other comorbidities.

RESUMEN: La disfunción reproductiva es una complicación por muchas enfermedades y toxinas. Su diagnóstico y tratamiento tempranos son inmensamente importantes. Aquí se evaluaron los cambios morfológicos en la histoarquitectura en la toxicidad precoz testicular y cauda antes y después del tratamiento con bloqueadores de receptores de angiotensina. Se indujo daño testicular de bajo grado usando tioacetamida (TAA, 50 mg / kg / día) por vía intraperitoneal durante dos semanas en ratas. Las ratas se dividieron aleatoriamente en cuatro grupos (n = 8) tratados diariamente por vía oral durante tres semanas de la siguiente manera: control normal (agua destilada), TAA (control positivo), TAA + candesartan (0,2 mg / kg) y TAA + losartán (7,5 mg / kg). Se midieron la testosterona sérica, el malondialdehído testicular y el glutatión. Los cambios en la histoarquitectura de los testículos y la epidermis de la cauda se evaluaron mediante Hematoxilina y Eosina para determinar la estructura general, con tricrómicro de Masson para el colágeno, ácido periódico de Schiff para la membrana basal y la caspasa-3 y el antígeno nuclear de células proliferantes (PCNA) para análisis inmunohistoquímico. Las ratas TAA mostraron disminución de la testosterona sérica y glutatión testicular, aumentos en el malondialdehído testicular, cambios degenerativos y apoptosis en células germinales, engrosamiento de la lámina basal tubular y aumentos en la expresión de la caspasa 3, y disminución en la expresión de PCNA. Los ARB (candesartán y losartán) revirtieron significativamente estos cambios con diferencias no significativas en el medio. El tratamiento con BRA (candesartán y losartán) revirtió significativamente la toxicidad testicular y cauda inducida por TAA en ratas. Esto podría ser potencialmente útil para el tratamiento temprano de pacientes con disfunción reproductiva inducida por tóxicos ocupacionales, especialmente si están usando BRA para otras comorbilidades.

Pine ( Pinus densiflora ) needle extract could promote the expression of PCNA and Ki-67 after partial hepatectomy in rat

Abstract Purpose To investigate the effects of pine needle extract (PNE) on the expression of proliferating cell nuclear antigen (PCNA) and Ki-67 during liver regeneration induced by 70% partial hepatectomy (PH) in rat. Methods Forty-eight male rats (SD, 7 weeks) had surgery (70% PH). They were randomly divided into two groups. PH + PNE group was only provided PNE diluted in water (10%) for drinking and PH group was provided water from 5 days before surgery to the time of sacrifice. PNE was made by pressing and filtering. Animals were sacrificed at 12h, 24h, 36h, 60h, 84h, 168h after PH, respectively. The expressions of PCNA and Ki-67 were determined as proliferation indices. Results Immunohistochemistry turned out to increase the expression of PCNA and Ki-67. PCNA expression of PH+PNE group increased up to twice of that of PH group. Western blot also seemed to increase the PCNA expression. These results indicated the promotion of cell proliferation in liver tissue and hepatic regeneration. Conclusions Pine needle extract stimulates the expression of some mitotic proteins during liver regeneration induced by 70% PH in rats. It suggests that administration of pine needle extract could accelerate the liver regeneration after partial hepatectomy.

Propofol attenuates cytokine-mediated upregulation of expression of inducible nitric oxide synthase and apoptosis during regeneration post-partial hepatectomy

Abstract Purpose: To determine the effects of propofol and ketamine anesthesia on liver regeneration in rats after partial hepatectomy (PHT). Methods: Male Wistar albino rats were assigned randomly to four groups of 10. Anesthesia was induced and maintained with propofol in groups 1 and 2, and with ketamine in groups 3 and 4. PHT was undertaken in groups 1 and 3. Rats in groups 2 and 4 (control groups) underwent an identical surgical procedure, but without PHT. At postoperative day-5, rats were killed. Regenerated liver was removed, weighed, and evaluated (by immunohistochemical means) for expression of inducible nitric oxide synthase (iNOS), endothelial NOS (eNOS), apoptosis protease-activating factor (APAF)-1, and proliferating cell nuclear antigen (PCNA). Also, blood samples were collected for measurement of levels of tumor necrosis factor (TNF)-α and interleukin (IL)-6. Results: Between groups 2 and 4, there were no differences in tissue levels of iNOS, eNOS, and APAF-1 or plasma levels of TNF-α and IL-6. eNOS expression was similar in group 1 and group 3. Expression of iNOS and APAF-1 was mild-to-moderate in group 1, but significantly higher in group 3. Groups 1 and 3 showed an increase in PCNA expression, but expression in both groups was comparable. Plasma levels of TNF-α and IL-6 increased to a lesser degree in group 1 than in group 3. Conclusion: Propofol, as an anesthetic agent, may attenuate cytokine-mediated upregulation of iNOS expression and apoptosis in an animal model of liver regeneration after partial hepatectomy.

Frequent users of emergency services: associated factors and reasons for seeking care / Usuários frequentes de serviço de emergência: fatores associados e motivos de busca por atendimento / Usuarios frecuentes de servicios de emergencia: factores asociados y motivos de la búsqueda de atención

Aim: to identify the profile of frequent users of emergency services, to verify the associated factors and to analyze the reasons for the frequent use of the services. METHOD: An explanatory sequential type mixed method was adopted. Quantitative data were collected from the electronic medical records, with a sample of 385 users attended four or more times in an emergency service, during the year 2011. Qualitative data were collected through semi-structured interviews with 18 users, intentionally selected from the results of the quantitative stage. Quantitative data were analyzed using descriptive and inferential statistics and qualitative data using thematic analysis. RESULTS: It was found that 42.9% were elderly, 84.9% had chronic diseases, 63.5% were classified as urgent, 42.1% stayed for more than 24 hours in the service and 46.5% were discharged. Scheduled follow-up appointment, risk classification, length of stay and outcome were factors associated with frequent use. The reasons for seeking the services were mainly related to the exacerbation of chronic diseases, to easier access and concentration of technology, to the bond, and to the scheduled appointments. CONCLUSIONS: The results contribute to comprehending the repeated use of emergency services and provide additional data to plan alternatives to reduce frequent use. .

OBJETIVO: identificar o perfil de usuários frequentes de serviço de emergência, verificar fatores associados e analisar os motivos para utilização frequente do serviço. MÉTODO: adotou-se método misto, do tipo sequencial explanatório. Os dados quantitativos foram coletados em registros de prontuários eletrônicos, com amostra de 385 usuários, atendidos quatro vezes ou mais em um serviço de emergência, durante o ano de 2011. Os dados qualitativos foram obtidos por meio de entrevistas semiestruturadas, com 18 usuários, selecionados intencionalmente a partir dos resultados da etapa quantitativa. Os dados quantitativos foram analisados com estatística descritiva e inferencial e os qualitativos com análise temática. RESULTADOS: identificou-se que 42,9% eram idosos, 84,9% tinham doenças crônicas, 63,5% foram classificados como urgentes, 42,1% permaneceram mais de 24 horas no serviço e 46,5% tiveram alta. Os fatores associados à utilização frequente são retorno agendado, classificação de risco, tempo de permanência e desfecho. Os motivos da busca pelo serviço são relacionados, principalmente, à agudização de doenças crônicas, maior facilidade de acesso, concentração de tecnologia, vínculo e retornos agendados. CONCLUSÕES: os resultados contribuem para compreensão do uso repetido de serviços de emergência e oferecem subsídios para planejamento de alternativas para redução da utilização frequente. .

OBJETIVO: identificar el perfil de usuarios frecuentes de servicios de emergencia, verificar los factores asociados y analizar los motivos para utilización frecuente de ese servicio. MÉTODO: se adoptó un método mixto del tipo secuencial explicativo. Los datos cuantitativos fueron recolectados en registros de fichas electrónicas, con muestra de 385 usuarios atendidos cuatro veces o más, en un servicio de emergencia, durante el año de 2011. Los datos cualitativos fueron obtenidos por medio de entrevistas semiestructuradas con 18 usuarios, seleccionados intencionalmente a partir de los resultados de la etapa cuantitativa. Los datos cuantitativos fueron analizados con estadística descriptiva e inferencial y los cualitativos con análisis temático. RESULTADOS: se identificó que 42,9% eran ancianos, 84,9% tenían enfermedades crónicas, 63,5% fueron clasificados como urgentes, 42,1% permanecieron más de 24 horas en el servicio y 46,5% tuvieron alta para el domicilio. El retorno programado, la clasificación de riesgo, el tiempo de permanencia y el resultado, son factores asociados a la utilización frecuente. Los motivos de la búsqueda por el servicio son relacionados, principalmente a: la agudización de enfermedades crónicas, la mayor facilidad de acceso y concentración de tecnología, los vínculos, y a los retornos programados. CONCLUSIONES: los resultados contribuyen para la comprensión del uso repetido de servicios de emergencia y ofrecen informaciones para planificar alternativas para reducción de la utilización frecuente. .

La proliferación de los miocitos ventriculares del corazón de mamífero adulto: un fenómeno esporádico pero factible / Proliferation of adult mammalian ventricular cardiomyocytes: A sporadic but feasible phenomenon

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.

Protective effects of silymarin on fumonisin B1-induced hepatotoxicity in mice

The present study was conducted to investigate the effect of silymarin on experimental liver toxication induced by Fumonisin B1 (FB1) in BALB/c mice. The mice were divided into six groups (n = 15). Group 1 served as the control. Group 2 was the silymarin control (100 mg/kg by gavage). Groups 3 and 4 were treated with FB1 (Group 3, 1.5 mg/kg FB1, intraperitoneally; and Group 4, 4.5 mg/kg FB1). Group 5 received FB1 (1.5 mg/kg) and silymarin (100 mg/kg), and Group 6 was given a higher dose of FB1 (4.5 mg/kg FB1) with silymarin (100 mg/kg). Silymarin treatment significantly decreased (p < 0.0001) the apoptotic rate. FB1 administration significantly increased (p < 0.0001) proliferating cell nuclear antigen and Ki-67 expression. Furthermore, FB1 elevated the levels of caspase-8 and tumor necrosis factor-alpha mediators while silymarin significantly reduced (p < 0.0001) the expression of these factors. Vascular endothelial growth factor (VEGF) and fibroblast growth factor-2 (FGF-2) expressions were significantly elevated in Group 4 (p < 0.0001). Silymarin administration alleviated increased VEGF and FGF-2 expression levels (p < 0.0001). In conclusion, silymarin ameliorated toxic liver damage caused by FB1 in BALB/c mice.

Phytohemagglutinin improves the development and ultrastructure of in vitro-cultured goat (Capra hircus) preantral follicles

The objective this study was to determine the effect of phytohemagglutinin (PHA) on survival, growth and gene expression in caprine secondary follicles cultured in vitro. Secondary follicles (∼0.2 mm) were isolated from the cortex of caprine ovaries and cultured individually for 6 days in α-MEM+ supplemented with PHA (0, 1, 10, 50, 100, or 200 µg/mL). After 6 days of culture, follicle diameter and survival, antrum formation, ultrastructure and expression of mRNA for FSH receptors (FSH-R), proliferating cell nuclear antigen (PCNA), and neuronal nitric oxide synthase were determined. All treatments maintained follicular survival [α-MEM+ (94.59%); 1 µg/mL PHA (96.43%); 10 µg/mL PHA (84.85%); 50 µg/mL PHA (85.29%); 100 µg/mL PHA (88.57%), and 200 µg/mL PHA (87.50)], but the presence of 10 µg/mL PHA in the culture medium increased the antrum formation rate (21.21%) when compared with control (5.41%, P < 0.05) and ensured the maintenance of oocyte and granulosa cell ultrastructures after 6 days of culture. The expression of mRNA for FSH-R (2.7 ± 0.1) and PCNA (4.4 ± 0.2) was also significantly increased in follicles cultured with 10 µg/mL PHA in relation to those cultured in α-MEM+ (1.0 ± 0.1). In conclusion, supplementation of culture medium with 10 µg/mL PHA maintains the follicular viability and ultrastructure, and promotes the formation of antral cavity after 6 days of culture in vitro.

REGγ is a strong candidate for the regulation of cell cycle, proliferation and the invasion by poorly differentiated thyroid carcinoma cells

REGγ is a proteasome activator that facilitates the degradation of small peptides. Abnormally high expression of REGγ has been observed in thyroid carcinomas. The purpose of the present study was to explore the role of REGγ in poorly differentiated thyroid carcinoma (PDTC). For this purpose, small interfering RNA (siRNA) was introduced to down-regulate the level of REGγ in the PDTC cell line SW579. Down-regulation of REGγ at the mRNA and protein levels was confirmed by RT-PCR and Western blot analyses. FACS analysis revealed cell cycle arrest at the G1/S transition, the MTT assay showed inhibition of cell proliferation, and the Transwell assay showed restricted cell invasion. Furthermore, the expression of the p21 protein was increased, the expression of proliferating cell nuclear antigen (PCNA) protein decreased, and the expression of the p27 protein was unchanged as shown by Western blot analyses. REGγ plays a critical role in the cell cycle, proliferation and invasion of SW579 cells. The alteration of p21 and PCNA proteins related to the down-regulation of REGγ suggests that p21 and PCNA participate in the process of REGγ regulation of cell cycle progression and cell proliferation. Thus, targeting REGγ has a therapeutic potential in the management of PDTC patients.

Ozone Exposure Suppresses Proliferative Response in Mice Skin

No abstract available.

The effects of antidepressants and pilocarpine on rat parotid glands: an immunohistochemical study

OBJECTIVES: To evaluate the effects of antidepressants and pilocarpine on the quantity of myoepithelial cells and on the proliferation index of the epithelial cells of rat parotid glands. INTRODUCTION: Hyposalivation, xerostomia, and alterations in saliva composition are important clinical side effects related to the use of antidepressants. METHODS: Ninety male Wistar rats were allocated to nine groups. The control groups received saline for 30 (group C30) or 60 days (group C60) or pilocarpine for 60 days (group Pilo). The experimental groups were administered fluoxetine (group F30) or venlafaxine for 30 days (group V30); fluoxetine (group FS60) or venlafaxine (group VS60) with saline for 60 days; or fluoxetine (group FP60) or venlafaxine (group VP60) with pilocarpine for 60 days. Parotid gland specimens were processed, and the immunohistochemical expression of calponin and proliferating cell nuclear anti-antigen on the myoepithelial and parenchymal cells, respectively, was evaluated. Analysis of variance (ANOVA), Tukey HSD and Games-Howell tests were applied to detect differences among groups (p<0.05). RESULTS: Compared with the controls, chronic exposure to antidepressants was associated with an increase in the number of positively stained cells for calponin. In addition, venlafaxine administration for 30 days was associated with an increase in the number of positively stained cells for proliferating cell nuclear anti-antigen. Fluoxetine and pilocarpine (group FP60) induced a significant decrease in the number of positively stained cells for calponin compared with all other groups. CONCLUSIONS: The number of positively stained cells for calponin increased after chronic administration of antidepressants. The proliferation index of the epithelial cells of rat parotid glands was not altered by the use of antidepressants for 60 days.

The effect of preconditioning on liver regeneration after hepatic resection in cirrhotic rats / 대한간학회지

BACKGROUND/AIMS: Ischemic preconditioning (IP) decreases severity of liver necrosis and has anti-apoptotic effects in previous studies using liver regeneration in normal rats. This study assessed the effect of IP on liver regeneration after hepatic resection in cirrhotic rats. METHODS: To induce liver cirrhosis, thioacetamide (300 mg/kg) was injected intraperitoneally into Sprague-Dawley rats twice per week for 16 weeks. Animals were divided into four groups: non-clamping (NC), total clamping (TC), IP, and intermittent clamping (IC). Ischemic injury was induced by clamping the left portal pedicle including the portal vein and hepatic artery. Liver enzymes alanine transaminase (ALT) and aspartate aminotransferase (AST) were measured to assess liver damage. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) staining for apoptosis and proliferating cell nuclear antigen (PCNA) staining for cell replication were also performed. RESULTS: Day-1 ALT and AST were highest in IP, however, levels in NC and IC were comparably low on days 1-7. There was no significant correlation of AST or ALT with experimental groups (P=0.615 and P=0.186). On TUNEL, numbers of apoptotic cells at 100x magnification (cells/field) were 31.8+/-24.2 in NC, 69.0+/-72.3 in TC, 80.2+/-63.1 in IP, and 21.2+/-20.8 in IC (P<0.05). When regeneration capacity was assessed by PCNA staining, PCNA-positive cells (cells/field) at 400x were 3.4+/-6.0 in NC, 16.9+/-69 in TC, 17.0+/-7.8 in IP and 7.4+/-7.6 in IC (P<0.05). CONCLUSIONS: Although regeneration capacity in IP is higher than IC, the liver is vulnerable to ischemic damage in cirrhotic rats. Careful consideration is needed in applying IP in the clinical setting.

Aldosterone Modulates Cell Proliferation and Apoptosis in the Neonatal Rat Heart

In the present study, we investigated whether and how the mineralocorticoid receptor antagonist spironolactone affects cardiac growth and development through apoptosis and cell proliferation in the neonatal rat heart. Newborn rat pups were treated with spironolactone (200 mg/kg/d) for 7 days. The cell proliferation was studied by PCNA immunostaining. The treatment with spironolactone decreased proliferating myocytes by 32% (P<0.05), and reduced myocytes apoptosis by 29% (P<0.05). Immunoblot and immunohistochemistry for the expression of p38, p53, clusterin, TGF-beta2, and extracellular signal-regulated kinase were performed. In the spironolactone group, p38, p53, clusterin, and TGF-beta2 protein expression was significantly decreased (P<0.05). These results indicate that aldosterone inhibition in the developing rat heart induces cardiac growth impairment by decreasing proliferation and apoptosis of myocytes.

The influence of estrogen on liver regeneration: an experimental study in rats / A influência do estrogênio na regeneração hepática: estudo experimental em ratos

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.

Endothelin A Receptor Blockade Influences Apoptosis and Cellular Proliferation in the Developing Rat Kidney

Endothelin systems are believed to play important roles in the emergence and maintenance of functions of various organs during perinatal development, including the kidney. The present study was designed to investigate the roles of endothelin systems on physiologic renal growth and development. Newborn rat pups were treated with either Bristol-Myers Squibb-182874 (30 mg/kg/day), a selective endothelin A receptor (ET(A)R) antagonist, or vehicle for 7 days. To identify cellular changes, kidneys were examined for apoptotic cells by terminal deoxynucleotide transferasemediated nick-end labeling stain and proliferating cell nuclear antigen (PCNA) by immunohistochemical (IHC) stain. To clarify the molecular control of these processes, immunoblots and reverse transcriptase-polymerase chain reaction for Clusterin, Bcl-2, Bcl-X(L), Bax, and p53 were performed. ETAR antagonist treatment resulted in reduced kidney weights, decreased PCNA-positive proliferating cells, and increased apoptotic cells. The protein expressions of renal Bcl-X(L) and Bax in the ETAR antagonist-treated group were significantly decreased, whereas the mRNA expressions of these genes were not changed. There were no significant differences in the expressions of Clusterin, Bcl-2, and p53. In conclusion, inhibition of endogenous endothelins impairs renal growth, in which decreased cellular proliferation, increased apoptosis and decreased expressions of renal Bcl-X(L) and Bax are possibly implicated.

DNA repair by polymerase delta in Saccharomyces cerevisiae is not controlled by the proliferating cell nuclear antigen-like Rad17/Mec3/Ddc1complex

DNA damage activates several mechanisms such as DNA repair and cell cycle checkpoints. The Saccharomyces cerevisiae heterotrimeric checkpoint clamp consisting of the Rad17, Mec3 and Ddc1 subunits is an early response factor to DNA damage and activates checkpoints. This complex is structurally similar to the proliferating cell nuclear antigen (PCNA), which serves as a sliding clamp platform for DNA replication. Growing evidence suggests that PCNA-like complexes play a major role in DNA repair as they have been shown to interact with and stimulate several proteins, including specialized DNA polymerases. With the aim of extending our knowledge concerning the link between checkpoint activation and DNA repair, we tested the possibility of a functional interaction between the Rad17/Mec3/Ddc1 complex and the replicative DNA polymerases alpha, delta and epsilon. The analysis of sensitivity response of single and double mutants to UVC and 8-MOP + UVA-induced DNA damage suggests that the PCNA-like component Mec3p of S. cerevisiae neither relies on nor competes with the third subunit of DNA polymerase delta, Pol32p, for lesion removal. No enhanced sensitivity was observed when inactivating components of DNA polymerases alpha and epsilon in the absence of Mec3p. The hypersensitivity of pol32delta to photoactivated 8-MOP suggests that the replicative DNA polymerase delta also participates in the repair of mono- and bi-functional DNA adducts. Repair of UVC and 8-MOP + UVA-induced DNA damage via polymerase delta thus occurs independent of the Rad17/Mec3/Ddc1 checkpoint clamp.

Selective expression of progesterone receptor in malignant melanoma was inversely correlated with PCNA / 华中科技大学学报（医学）（英德文版）

To investigate the role of progesterone receptor (PR) expression in malignant melanoma (MM), PR and proliferative cell nuclear antigen (PCNA) expression were immunohistochemistrically evaluated in a series of 35 specimens of MM, and the correlation between the immunohistochemistrical findings and clinicopathological data was also analyzed. PR expression was detected in 25.7% (9/35) of the patients with MM. No PR expression was observed in nevi. PR expression was inversely correlated with PCNA expression (r=-0.353, P=0.026). PR expression was slightly increased in females, subjects aged under 55 y, those with ulceration, non-acral subtype and diagnosis delay longer than 1 y, but the difference was not statistically significant. Selective expression of progesterone receptor in malignant melanoma might be correlated with inhibited tumor growth.

Efficacy of estriol in inhibiting epithelial proliferation in mammary fibroadenoma: randomized clinical trial

CONTEXT AND OBJECTIVE: Mammary fibroadenoma is a disease that affects a large number of women of reproductive age. The aim of this study was to evaluate the proliferative activity of mammary fibroadenoma through expression of Ki-67 and c-myc antigens, following administration of oral contraceptive with or without estriol. DESIGN AND SETTING: Placebo-controlled double-blind randomized clinical trial in the Mastology Sector of the Department of Gynecology, Universidade Federal de São Paulo. METHODS: Thirty-three fibroadenoma patients were studied. Ten women (group 1) took an oral contraceptive constituted by levonorgestrel and ethinyl estradiol together with placebo manufactured in the same capsule for four consecutive cycles with a seven-day interval between them. The other 23 patients (group 2) took the same oral contraceptive together with estriol, which was put into the same capsule and used in the same way as among the group 1 patients. After four cycles, the nodules were surgically removed and sent for immunohistochemical analysis of Ki-67 and c-myc expression. RESULTS: The Ki-67 and c-myc analysis did not reveal any significant differences between the study groups. The values were 9.16 and 10.54 for group 1 and 10.86 and 17.03 for group 2, respectively. There was a tendency towards higher expression of antigens in group 2. CONCLUSION: Our results showed that there was no significant statistical difference in Ki-67 and c-myc expression between our study groups, but only a tendency towards higher expression among users of oral contraceptives containing estriol.

CONTEXTO E OBJETIVO: O fibroadenoma mamário é uma doença que atinge um grande número de mulheres na idade reprodutiva. O objetivo foi avaliar a atividade proliferativa do fibroadenoma mamário, através da expressão do Ki-67 e do c-myc, após a administração de anticoncepcional oral, associado ou não ao estriol. TIPO DE ESTUDO E LOCAL: Ensaio clínico randomizado, duplo-cego, placebo controlado, realizado na Universidade Federal de São Paulo a nível terciário. MÉTODOS: Foram estudadas 33 pacientes portadoras de fibroadenoma, atendidas no setor de Mastologia da Disciplina de Ginecologia da Universidade Federal de São Paulo - Escola Paulista de Medicina (Unifesp-EPM), sendo que 10 mulheres constituíram o grupo 1, e utilizaram anticoncepcional oral composto de levonorgestrel e etinilestradiol, associados a placebo na mesma cápsula por quatro ciclos consecutivos, com intervalo de sete dias entre cada um. As restantes 23 pacientes alocaram-se no grupo 2 e ingeriram, além do anticoncepcional oral descrito acima, um comprimido de estriol, que foi manufaturado na mesma cápsula e foi utilizado da mesma forma que nas pacientes do grupo 1. Ao final dos quatro ciclos, praticou-se a exérese cirúrgica dos nódulos, com posterior envio para análise imunoistoquímica de Ki-67 e c-myc. RESULTADOS: A análise com Ki-67 e c-myc não revelou diferença significante entre os grupos estudados, que foi de 9,16 e 10,54 no grupo 1 e de 10,86 e 17,03 no grupo 2, respectivamente, apesar de ter havido tendência a maior expressão dos marcadores entre as pacientes do grupo 2. CONCLUSÃO: Nossos resultados demonstram não haver diferença estatisticamente significante na expressão de Ki-67 e de c-myc entre os grupos em estudo, apenas uma tendência a sua maior expressão entre as usuárias de anticoncepcional e estriol.

Response of the growth plate of uremic rats to human growth hormone and corticosteroids

Children with chronic renal failure in general present growth retardation that is aggravated by corticosteroids. We describe here the effects of methylprednisolone (MP) and recombinant human growth hormone (rhGH) on the growth plate (GP) of uremic rats. Uremia was induced by subtotal nephrectomy in 30-day-old rats, followed by 20 IU kg-1 day-1 rhGH (N = 7) or 3 mg kg-1 day-1 MP (N = 7) or 20 IU kg-1 day-1 rhGH + 3 mg kg-1 day-1 MP (N = 7) treatment for 10 days. Control rats with intact renal function were sham-operated and treated with 3 mg kg-1 day-1 MP (N = 7) or vehicle (N = 7). Uremic rats (N = 7) were used as untreated control animals. Structural alterations in the GP and the expression of anti-proliferating cell nuclear antigen (PCNA) and anti-insulin-like growth factor I (IGF-I) by epiphyseal chondrocytes were evaluated. Uremic MP rats displayed a reduction in the proliferative zone height (59.08 ± 4.54 vs 68.07 ± 7.5 æm, P < 0.05) and modifications in the microarchitecture of the GP. MP and uremia had an additive inhibitory effect on the proliferative activity of GP chondrocytes, lowering the expression of PCNA (19.48 ± 11.13 vs 68.64 ± 7.9 percent in control, P < 0.0005) and IGF-I (58.53 ± 0.96 vs 84.78 ± 2.93 percent in control, P < 0.0001), that was counteracted by rhGH. These findings suggest that in uremic rats rhGH therapy improves longitudinal growth by increasing IGF-I synthesis in the GP and by stimulating chondrocyte proliferation.

Sulindac Prevents Esophageal Adenocarcinomas Induced by Gastroduodenal Reflux in Rats

PURPOSE: It is known that cyclooxygenase (COX)-2 expression is increased in Barrett's esophagus and esophageal adenocarcinomas. We studied COX-2 expression and the effect sulindac has on the genesis of Barrett's esophagus and adenocarcinoma in rats undergoing esophagogastroduodenal anastomosis (EGDA). MATERIALS AND METHODS: Fifty-one rats were divided into a control group (n=27), a 500ppm sulindac-treated group (n=15) and 1000 ppm sulindac-treated group (n=9). Randomly selected rats were killed by diethyl ether inhalation at 20 and 40 weeks after surgery. RESULTS: At 40 weeks, rats treated with 1000 ppm sulindac showed narrower esophageal diameter and milder inflammation than the control rats. At 40 weeks, the incidence of Barrett's esophagus was similar between control and sulindac-treated groups, but the incidence of adenocarcinoma was significantly lower in the 1000ppm sulindac-treated group than either the control or 500 ppm sulindac-treated groups. COX-2 was significantly increased in the lower esophagus of control rats killed at 40 weeks. Cyclin D1 expression was negligible in the sulindac- treated group compared with the control group. CONCLUSION: We suggest that the chemopreventive effect of sulindac is related to decreased COX-2 and cyclin D1 expression, which may be influenced by reduced inflammation.