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BACKGROUND: Graft-versus-host disease (GVHD) is an immune system reaction that occurs in patients with a history of hematopoietic stem cell transplantation (HSCT), in which the grafted donor's cells attack those of the host. The objective of this systematic review was to present a study on oral squamous cell carcinoma (OSSC) that developed from GVHD areas in patients undergoing HSCT. MATERIAL AND METHODS: An electronic search was conducted in the databases PUBMED, WEB OF SCIENCE, SCOPUS, MEDLINE and SCIENCE DIRECT, according to PRISMA guidelines. RESULTS: Of the 1582 results, 23 articles were included, resulting in 81 cases. The most common underlying disease for performing the transplant was Myeloid Leukemia (55.6%). The mean age was 39 years, with a predilection for males (64.2%). The tongue was the site of GVHD that most frequently underwent transformation to SCC (59.3%). The average time between transplantation and the development of GVHD was of approximately of 8 months, while the average period of development between transplantation and the development of OSCC was of approximately of 111 months. The most common treatment to GVHD was cyclosporine associated with corticosteroids. CONCLUSIONS: OSCCs arising from areas of GVHD present a different evolution from conventional oral carcinomas, since they affect younger patients, smoking and alcohol are not important etiological factors and finally because they present good prognosis, but further studies with larger number cases followed are needed to confirm our findings.
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Carcinoma de Células Escamosas , Enfermedad Injerto contra Huésped , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Masculino , Humanos , Adulto , Carcinoma de Células Escamosas/complicaciones , Carcinoma de Células Escamosas de Cabeza y Cuello/complicaciones , Neoplasias de la Boca/etiología , Enfermedad Injerto contra Huésped/complicaciones , Neoplasias de Cabeza y Cuello/complicacionesRESUMEN
BACKGROUND: This study aimed to explore the clinical, histopathologic, and immunohistochemical characteristics of myofibromas (MFs) affecting the head and neck region. MATERIAL AND METHODS: Formalin-fixed paraffin-embedded tissue blocks of patients diagnosed with MFs in the head and neck were retrieved from the archives of three oral and maxillofacial pathology laboratories. Data including clinical, radiographic, microscopic and immunohistochemical findings, treatment employed, and follow-up status were retrieved from the patient's medical records or pathology reports. RESULTS: Sixteen cases were included in the study. Females were slightly more affected than males. The first and second decades of life were more prevalent. The most common locations were the alveolar ridge and cheek. Although rare, some of the patients were presented with intraosseous lesions. Microscopically, tumors consisted of plump, spindle-shaped myofibroblasts arranged in whorls or fascicles with varying degrees of differentiation. Immunohistochemically, diffuse positivity for vimentin and α-SMA was observed, while Ki-67 mostly showed low immunoreactivity (<5%). Treatment primarily involved complete excision. CONCLUSIONS: MFs in the head and neck region are rare and predominantly affect female patients during the second decade of life. Despite their rarity, central MFs should be considered in the differential diagnosis of intraosseous lesions in infants.
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BACKGROUND: To evaluate the prevalence and clinicopathological features of a large series of gingival neoplasms in Brazil. MATERIAL AND METHODS: All gingival benign and malignant neoplasms were retrieved from the records of six Oral Pathology Services in Brazil, during a 41-year period. Clinical and demographic data, clinical diagnosis, and histopathological data were collected from the patients' clinical charts. For statistical analysis, the chi-square, median test of independent samples and the U Mann-Whitney tests were used, considering a significance of 5%. RESULTS: From 100,026 oral lesions, 888 (0.9%) were gingival neoplasms. There were 496 (55.9%) males, with a mean age of 54.2 years. Most cases (70.3%) were malignant neoplasms. Nodules (46.2%) and ulcers (38.9%) were the most common clinical appearance for benign and malignant neoplasms, respectively. Squamous cell carcinoma (55.6%) was the most common gingival neoplasm, followed by squamous cell papilloma (19.6%). In 69 (11.1%) malignant neoplasms, the lesions were clinically considered to be inflammatory or of infectious origin. Malignant neoplasms were more common in older men, appeared with larger size, and with a time of complaint shorter than benign neoplasms (p<0.001). CONCLUSIONS: Benign and malignant tumors may appear as nodules in gingival tissue. In addition, malignant neoplasms, especially squamous cell carcinoma, should be considered in the differential diagnosis of persistent single gingival ulcers.
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Carcinoma de Células Escamosas , Neoplasias Gingivales , Úlceras Bucales , Masculino , Humanos , Anciano , Persona de Mediana Edad , Femenino , Neoplasias Gingivales/patología , Brasil/epidemiología , Úlcera/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/patología , Diagnóstico Diferencial , Estudios RetrospectivosRESUMEN
BACKGROUND: HIV-related non-Hodgkin lymphomas of the oral cavity are rare lesions with aggressive clinical behaviour. The aim of this study is to describe the clinicopathological features of a series of HIV-related oral non-Hodgkin lymphomas. MATERIAL AND METHODS: Eleven cases of oral lymphomas affecting HIV-positive patients were retrieved from 2012 to 2019. Clinicopathological features regarding age, sex, tumour location, clinical presentation, laboratory findings, disease stage and follow-up were obtained. Histologic, immunohistochemical and in situ hybridization for EBV detection were done for diagnosis confirmation. Overall survival was estimated by Kaplan-Meier curve. RESULTS: Males predominated, with a mean age of 40.3 years-old. Maxilla and mandible were the mostly affected. Plasmablastic lymphoma and diffuse large B-cell lymphoma not otherwise specified (NOS) were the main histological types. Lesions presented as reddish ulcerated swellings, representing the first sign of AIDS in six cases. Stage IV were common (7 cases) and the mean HIV viral load was 10,557 copies/mL, with a mean of 266 CD4+ cells/mm3, 1,278 CD8+ cells/mm3 and a CD4+/CD8+ ratio of 0.26. Eight patients died of the disease (72.7%). Overall survival revealed that 78.2% of the patients died after 21 months of follow-up. CONCLUSIONS: HIV-related oral lymphomas present a poor prognosis usually diagnosed in advanced stages and in our series plasmablastic lymphoma was the most common subtype.
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Infecciones por VIH , Linfoma de Células B Grandes Difuso , Linfoma no Hodgkin , Adulto , Infecciones por VIH/complicaciones , Humanos , Hibridación in Situ , Linfoma de Células B Grandes Difuso/diagnóstico , Linfoma de Células B Grandes Difuso/patología , Linfoma no Hodgkin/diagnóstico , Linfoma no Hodgkin/patología , Masculino , Boca/patologíaRESUMEN
BACKGROUND: Kaposi's sarcoma (KS) is an uncommon, multifocal and angioproliferative lesion, which demonstrates a poor prognosis. The aim of the present research was to explore the association of HIV viral load, CD4+ and CD8+ counts and the CD4+/CD8+ ratio on the risk of oral Kaposi's sarcoma (KS) development. MATERIAL AND METHODS: A total of 62 patients were retrieved from March 2008 to October 2020 from the files of two oral pathology centres. Clinical, laboratory and follow-up data were retrieved from their medical files. Poisson regression was used to explore the role of history of immunosuppression and its association with oral KS development. A P-value <0.05 was considered significant. RESULTS: Sixty-two patients were included in the present study (32 with oral KS and 30 with no presentation of lesions anywhere on the body). Patients with oral KS presented a mean age of 32.6 years, and male patients were more affected. The hard palate (15 cases; 46.8%) was the main anatomical site affected. The lesions were mostly presented as swellings (13 cases; 40.6%) and nodules (12 cases; 37.5%). Systemic manifestations were also observed, including candidiasis (4 cases; 12.5%), bacterial infection (3 cases; 9.3%), tuberculosis (3 cases; 9.3%), herpes simplex (3 cases; 9.3%) and pneumonia (3 cases; 9.3%). A significant correlation was observed between HIV viral load, CD4+ count and the CD4+/CD8+ ratio with oral KS development. CONCLUSIONS: HIV viral load, CD4+ count and the CD4+/CD8+ ratio are associated with oral KS development.
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Infecciones por VIH , Sarcoma de Kaposi , Adulto , Recuento de Linfocito CD4 , Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos , Infecciones por VIH/complicaciones , Humanos , Masculino , Sarcoma de Kaposi/complicaciones , Carga ViralRESUMEN
BACKGROUND: The aim of this study was to investigate the frequency of oral lesions in the floor of the mouth from representative oral pathology centres in Latin America. MATERIAL AND METHODS: This study was conducted on biopsies obtained from January of 1978 to December of 2018 at nine Latin America oral and maxillofacial pathology centres. Gender, age and histopathological diagnosis were evaluated. Data were analysed using descriptive methods. Chi-square test was used for pairwise comparisons. RESULTS: From 114,893 samples, 4,016 lesions (3.49%) occurred in the floor of the mouth. Brazil showed 3,777 cases (94%), Mexico 182 cases (4.5%) and Argentina 57 cases (1.4%). Benign lesions represented 65.1% (2,617 cases), followed by 34.9% (1,404 cases) of malignant disorders. Lesions of epithelial origin were more frequent (1,964 cases; 48.9%), followed by salivary glands (1,245 cases; 31%) and soft tissue lesions (475 cases; 11.7%). The most common histological subtypes were oral squamous cell carcinoma (1,347 cases; 33.5%), ranula (724 cases; 18%), oral leukoplakia (476 cases; 11.8%) and inflammatory fibrous hyperplasia (239 cases; 5.9%). The lesion affected males in 2,129 cases and females in 1,897 cases. CONCLUSIONS: In the current study, lesions in the floor of the mouth represented 3.49% of biopsies submitted to oral pathology services and oral squamous cell carcinoma, ranula and leukoplakia were the most common lesions.
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Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Enfermedades de la Boca , Neoplasias de la Boca , Femenino , Humanos , Leucoplasia Bucal , Masculino , Enfermedades de la Boca/epidemiología , Mucosa Bucal , Neoplasias de la Boca/epidemiología , Estudios RetrospectivosRESUMEN
BACKGROUND: To describe the clinicopathological characteristics of a series of head and neck rhabdomyosarcoma (RMS) and to review the literature. MATERIAL AND METHODS: Cases diagnosed as RMS affecting the head and neck region were retrospectively retrieved from the files of two Brazilian institutions from January 2006 to January 2017. Data on clinical features (sex, age and affected site), microscopic subtype, immunohistochemical results, treatment employed and follow-up status were obtained from the patient's medical charts. RESULTS: During the period considered, 10 cases of RMS were identified. Females predominated (4M:6F), the mean age at diagnosis was 16.5 years-old and the orbit was the most affected site (4 cases). Microscopically, most cases were classified as embryonal RMS (6 cases) and the Desmin/Myogenin/Myo-D1 immunohistochemical positivity was useful to confirm the diagnosis. Chemotherapy and radiotherapy were applied to 9 and 8 patients respectively, whereas 2 patients were treated by surgery. Recurrences occurred in 3 patients and distant metastasis in 2 cases. Nine patients were alive in their last follow-up, 3 of them with disease, whereas 1 patient died due to the disease. CONCLUSION: Head and neck RMS is an aggressive malignant neoplasm which demands especial concern to achieve early diagnosis and successful treatment.
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Neoplasias de Cabeza y Cuello/diagnóstico , Rabdomiosarcoma/diagnóstico , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Estudios Retrospectivos , Adulto JovenRESUMEN
Neuromedin B (NB) and gastrin-releasing peptide (GRP) are bombesin-like peptides, found in the gastrointestinal tube and pancreas, among other tissues. Consistent data proposed that GRP stimulates insulin secretion, acting directly in pancreatic cells or in the release of gastrointestinal hormones that are incretins. However, the role of NB remains unclear. We examined the glucose homeostasis in mice with deletion of NB receptor (NBR-KO). Female NBR-KO exhibited similar fasting basal glucose with lower insulinemia (48.4%) and lower homeostasis model assessment of insulin resistance index (50.5%) than wild type (WT). Additionally, they were more tolerant to oral glucose, demonstrated by a decrease in the area under the glucose curve (18%). In addition, 15 min after an oral glucose load, female and male NBR-KO showed lower insulin serum levels (45.6 and 26.8%, respectively) than WT, even though blood glucose rose to similar levels in both groups. Single injection of NB, one hour before the oral glucose administration, tended to induce higher serum insulin in WT (28.9%, p=0.3), however the same did not occur in NBR-KO. They showed no changes in fasting insulin content in pancreatic islets by immunohistochemistry, however, the fasting serum levels of glucagon-like peptide, a potent incretin, exhibited a strong trend to reduction (40%, p=0.07). Collectively, mice with deletion of NB receptor have lower insulinemia, especially in response to oral glucose, and females also exhibited a better glucose tolerance, suggesting the involvement of NB and its receptor in regulation of insulin secretion induced by incretins, and also, in insulin sensitivity.
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Eliminación de Gen , Glucosa/administración & dosificación , Glucosa/farmacología , Insulina/metabolismo , Receptores de Bombesina/metabolismo , Administración Oral , Animales , Ayuno , Femenino , Glucagón/metabolismo , Péptido 1 Similar al Glucagón/metabolismo , Prueba de Tolerancia a la Glucosa , Homeostasis/efectos de los fármacos , Islotes Pancreáticos/efectos de los fármacos , Islotes Pancreáticos/patología , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Neuroquinina B/administración & dosificación , Neuroquinina B/análogos & derivados , Neuroquinina B/farmacología , Receptores de Bombesina/deficienciaRESUMEN
Hyperleptinemia during lactation programs for higher serum leptin in 30-day-old and adult rats, associated with metabolic changes. Here we evaluated the inhibition of serum leptin at 29 and 30 days on the metabolic phenotype of rats programmed with leptin during lactation. Pups from Wistar rats were saline-injected or leptin-injected from postnatal day 1 to day 10. At 29 and 30 days old, animals were injected with anti-leptin antibody (LA and CA) or saline (LS and CS). In adult animals, higher visceral (+53%) and total fat mass (+33%), hyperleptinemia (+67%), hypertriglyceridemia (+47%), and hypoadiponectinemia (-44%) observed in LS group compared to CS were prevented by immunoneutralization of leptin, since LA group had those parameters values similar to CS group. However, immunoblockade of leptin in normal animals led to the same metabolic changes seen in leptin-treated animals, in addition to lower serum adiponectin (-77% vs. CS) and higher insulin resistance index (+37%). Liver sirtuin1 (SIRT1) was higher (+41%) only in LA group, suggesting a role for SIRT1 in the prevention of leptin programming. Hypothalamic OBR was lower and SOCS3 higher in LS group and these changes were normalized in LA group. In conclusion, blocking leptin action one week after weaning seems to revert most of the alterations observed in rats programmed by neonatal hyperleptinemia. Higher liver SIRT1 expression may be one of the mechanisms involved, leading to a better glucose and lipid metabolism. Our data suggest that the lack or the excess of leptin programs an adverse metabolic phenotype in adulthood.
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Leptina/administración & dosificación , Obesidad/tratamiento farmacológico , Obesidad/prevención & control , Destete , Adiponectina/sangre , Animales , Glucemia/análisis , Femenino , Lactancia , Leptina/sangre , Hígado/metabolismo , Masculino , Obesidad/sangre , Obesidad/fisiopatología , Distribución Aleatoria , Ratas , Ratas Wistar , Sirtuina 1/genética , Sirtuina 1/metabolismoRESUMEN
The objective was to evaluate the available published data on sinonasal melanoma and analyse its clinical features, treatment modalities, and prognostic factors. An electronic search was undertaken in March 2018 in multiple databases. Eligibility criteria included publications with sufficient clinical, histological, and immunohistochemical information to confirm the diagnosis. Seventy-three publications (439 cases) were included. The lesion was more prevalent in females than in males. There was a higher prevalence in the seventh and eighth decades of life. The lesions mainly presented as epistaxis and commonly involved the nasal cavity. Age (>67.6 years; P=0.0012), primary location (middle turbinate; P=0.0112), disease stage (advanced disease stage; P=0.0026), treatment (radiotherapy; P=0.0111), recurrence (recurrence presented; P=0.0137), and distant metastasis (distant metastasis presented; P=0.0011) were independently associated with a lower survival rate. Recurrence was significantly correlated with age (>67.6 years; P=0.0021), sex (males tended to present a higher recurrence rate than females; P=0.0051), disease stage (stages III and IV presented a higher recurrence rate than stages I and II; P=0.0331), and histological type (amelanotic lesions presented a higher index of recurrence than melanotic lesions; P=0.0095). In conclusion, sinonasal melanoma is a neoplasm with a poor prognosis, presenting a 30.69% possibility of survival after 5 years.
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Melanoma , Recurrencia Local de Neoplasia , Femenino , Humanos , Masculino , Cavidad Nasal , Estadificación de Neoplasias , Pronóstico , Estudios RetrospectivosRESUMEN
The objective was to integrate the available published data on chondrosarcoma (CHS) of the jaw bones into a comprehensive analysis of its clinical and histological features, treatment, and prognostic factors. An electronic search was undertaken in October 2017. To be eligible, the publication had to provide sufficient clinical/histological data to confirm the diagnosis. One hundred and ten publications (224 cases of CHS) were identified and included. There was a slightly higher prevalence of CHS in males than in females. Most subjects with CHS were in the second to fifth decades of life. The most common symptom was swelling and the most commonly observed location was the maxilla. Histologically, most tumours were of the conventional type and were low grade tumours. The treatment of choice was tumour resection. Histological grade, treatment with chemotherapy alone, and the presentation of recurrence or metastasis were found to be significant independent prognostic factors: patients who presented high-grade tumours, who received chemotherapy alone as the treatment of choice, and those who presented recurrence or metastasis were more likely to have a worse prognosis. In addition, radical surgery associated with radiotherapy as the treatment protocol showed a better prognosis.
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Neoplasias Óseas , Condrosarcoma , Femenino , Humanos , Masculino , Recurrencia Local de Neoplasia , PronósticoRESUMEN
The present study investigated the prevalence of mutations in the -550 (H/L) and -221 (X/Y) mannose-binding lectin (MBL) gene promoter regions and their impact on infection by human immunodeficiency virus 1 (HIV-1) in a population of 128 HIV-1 seropositive and 97 seronegative patients. The allele identification was performed through the sequence-specific primer polymerase chain reaction method, using primer sequences specific to each polymorphism. The evolution of the infection was evaluated through CD4+ T-lymphocyte counts and plasma viral load. The allele and haplotype frequencies among HIV-1-infected patients and seronegative healthy control patients did not show significant differences. CD4+ T-lymphocyte counts showed lower levels among seropositive patients carrying haplotypes LY, LX and HX, as compared to those carrying the HY haplotype. Mean plasma viral load was higher among seropositive patients with haplotypes LY, LX and HX than among those carrying the HY haplotype. When promoter and exon 1 mutations were matched, it was possible to identify a significantly higher viral load among HIV-1 infected individuals carrying haplotypes correlated to low serum levels of MBL. The current study shows that haplotypes related to medium and low MBL serum levels might directly influence the evolution of viral progression in patients. Therefore, it is suggested that the identification of haplotypes within the promoter region of the MBL gene among HIV-1 infected persons should be further evaluated as a prognostic tool for AIDS progression.
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Infecciones por VIH/genética , VIH-1/genética , Lectina de Unión a Manosa/genética , Polimorfismo Genético/genética , Recuento de Linfocito CD4 , Estudios de Casos y Controles , Progresión de la Enfermedad , Marcadores Genéticos/genética , Predisposición Genética a la Enfermedad/genética , Infecciones por VIH/virología , Seronegatividad para VIH/genética , Haplotipos/genética , Humanos , Mutación , Reacción en Cadena de la Polimerasa , Regiones Promotoras Genéticas/genética , Carga ViralRESUMEN
Peptide YY (PYY)3-36 is a gut-derived hormone, with a proposed role in central mediation of postprandial satiety signals, as well as in long-term energy balance. In addition, recently, the ability of the hormone to regulate gonadotropin secretion, acting at pituitary and at hypothalamus has been reported. Here, we examined PYY3-36 effects on thyrotropin (TSH) secretion, both in vitro and in vivo. PYY3-36-incubated rat pituitary glands showed a dose-dependent decrease in TSH release, with 44 and 62% reduction at 10(-8) and 10(-6) M (P < 0.05 and P < 0.001 respectively), and no alteration in TSH response to thyrotropin-releasing hormone. In vivo, PYY3-36 i.p. single injection in the doses of 3 or 30 cg/kg body weight, administered to rats fed ad libitum, was not able to change serum TSH after 15 or 30 min. However, in fasted rats, PYY3-36 at both doses elicited a significant rise (approximately twofold increase, P < 0.05) in serum TSH observed 15 min after the hormone injection. PYY3-36 treatment did not modify significantly serum T4, T3, or leptin. Therefore, in the present paper, we have demonstrated that the gut hormone PYY3-36 acts directly on the pituitary gland to inhibit TSH release, and in the fasting situation, in vivo, when serum PYY3-36 is reduced, the activity of thyroid axis is reduced as well. In such a situation, systemically injected PYY3-36 was able to acutely activate the thyrotrope axis, suggesting a new role for PYY3-36 as a regulator of the hypothalamic-pituitary-thyroid axis.
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Ayuno/metabolismo , Péptido YY/farmacología , Adenohipófisis/metabolismo , Tirotropina/metabolismo , Animales , Células Cultivadas , Depresión Química , Relación Dosis-Respuesta a Droga , Leptina/sangre , Masculino , Adenohipófisis/efectos de los fármacos , Ratas , Ratas Wistar , Tirotropina/análisis , Tirotropina/sangre , Hormona Liberadora de Tirotropina/metabolismo , Hormona Liberadora de Tirotropina/farmacología , Tiroxina/sangre , Triyodotironina/sangreRESUMEN
Objetivou-se avaliar o desempenho bioeconômico de bezerros, nos primeiros 60 dias de vida, submetidos a três sistemas de aleitamento. Foram utilizados 24 bezerros (Holandês x Guzerá), sendo 12 machos e 12 fêmeas, com peso inicial de 32,25±4,8kg para as fêmeas e 36,92±6,8kg para os machos. Os animais foram distribuídos em delineamento inteiramente ao acaso, em esquema fatorial (3 x 2). Os bezerros receberam água à vontade e seis litros de sucedâneo lácteo por dia, durante 60 dias, em três estratégias diferentes, denominadas sistema de aleitamento (SA30: 3 litros de sucedâneo lácteo, duas vezes ao dia, até 30 dias de idade; SA45: 3 litros de sucedâneo lácteo, duas vezes ao dia, até 45 dias de idade; SA49: 3 litros de sucedâneo lácteo, duas vezes ao dia, até 49 dias de idade). Os sistemas de aleitamento estudados não apresentaram diferença estatística (P>0,05) para o consumo e a digestibilidade de nutrientes, com exceção para o consumo de matéria orgânica (MO) e extrato etéreo (EE). Verificou-se interação (P<0,05) entre o sistema de aleitamento e a classe sexual para os consumos de MO e EE, bem como para o ganho médio diário, em que os machos do SA 49 apresentaram maiores médias em relação ao SA 30. O desempenho bioeconômico de bezerros machos do sistema de aleitamento 49 foi superior e apresentou a melhor relação custo-benefício entre os sistemas estudados.(AU)
The objective of this study was to evaluate the bioeconomic performance of calves in the first 60 days of life submitted to three feeding systems. Twenty-four calves (Dutch x Guzerá) were used, 12 males and 12 females, with initial weight of 32.25±4.8kg for females and 36.92±6.8kg for males. The animals were distributed in a completely randomized design, in a factorial scheme (3 x 2). The calves received water at will and six liters of milk replacer a day for 60 days in three different strategies, called the suckling system (SA-30: 3 liters of milk replacer, twice a day until 30 days of age; SA-45: 3 liters of milk replacer, twice a day until 45 days of age; SA-49: 3 liters of milk replacer, twice daily up to 49 days old). The lactation systems studied did not present statistical difference (P>0.05) for the consumption and digestibility of nutrients, except for organic matter (OM) and ethereal extract (EE). There was an interaction (P<0.05) between the suckling system and sexual class for the OM and EE intakes, as well as for the average daily gain, in which HS 49 males presented higher averages in relation to SA 30. The bioeconomic performance of male calves from the lactation system 49 was superior and presented the best cost-benefit ratio among the systems studied.(AU)
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Animales , Bovinos , Crianza de Animales Domésticos , Lactancia Materna , Bovinos/metabolismoRESUMEN
BACKGROUND AND PURPOSE: Mounting evidence implicates matrix metalloproteinase (MMP) in the vascular dysfunction and remodelling associated with hypertension. We tested the hypothesis that treatment with pyrrolidine dithiocarbamate (PDTC), which interferes with NF-κB-induced MMPs gene transcription, could exert antihypertensive effects, prevent MMP-2 and MMP-9 up-regulation, and protect against the functional alterations and vascular remodelling of two-kidney, one clip (2K1C) hypertension. EXPERIMENTAL APPROACH: Sham-operated or hypertensive rats were treated with vehicle or PDTC (100 mg·Kg(-1) ·day(-1)) by gavage for 8 weeks. Systolic blood pressure (SBP) was monitored weekly. Aortic rings were isolated to assess endothelium-dependent relaxations. Quantitative morphometry of structural alterations of the aortic wall was carried out in haematoxylin/eosin sections. Formation of vascular reactive oxygen species (ROS), and inducible (i) NOS and phosphorylated-p65 NF-κB subunit expression were measured in the aortas. MMP-2 and MMP-9 aortic levels and gelatinolytic activity were determined by gelatin and in situ zymography and by immunofluorescence. KEY RESULTS: Treatment with PDTC attenuated the increases in SBP and prevented the endothelial dysfunction associated with 2K1C hypertension. Moreover, PDTC reversed the vascular aortic remodelling, the increases in aortic ROS levels and in iNOS and phosphorylated-p65 NF-κB expression found in 2K1C rats. These effects were associated with attenuation of 2K1C up-regulation of aortic MMP-2 and MMP-9 levels and gelatinolytic activity. CONCLUSION AND IMPLICATIONS: These findings suggest that PDTC down-regulates vascular MMPs and ameliorates vascular dysfunction and remodelling in renovascular hypertension, thus providing evidence supporting the suggestion that PDTC is probably a good candidate to be used to treat hypertension.
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Antihipertensivos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Hipertensión Renal/tratamiento farmacológico , Metaloproteasas/antagonistas & inhibidores , Pirrolidinas/farmacología , Tiocarbamatos/farmacología , Animales , Aorta/efectos de los fármacos , Aorta/fisiología , Hipertensión Renal/complicaciones , Hipertrofia/tratamiento farmacológico , Masculino , Metaloproteasas/metabolismo , FN-kappa B/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Ratas , Ratas WistarRESUMEN
Exonuclease III (Exo III) and endonuclease IV (Endo IV) play a critical role in the base excision repair (BER) of Escherichia coli. Both are endowed with AP endonucleolytic activity, cleaving the 5' phosphodiester bond adjacent to spontaneous or induced abasic sites in DNA. Although mutants defective in Exo III (xthA) are usually hypersensitive to oxidative agents such as hydrogen peroxide, near-UV-light and X-rays, mutants defective in Endo IV (nfo) are not as sensitive as the xthA strain. To further investigate the roles of these AP endonucleases in DNA repair, we evaluated the sensitivity and mutagenesis of xthA and nfo strains after UVB and compared with UVC light. Our results revealed that xthA but not nfo strain was hypersensitive to UVB. The use of Fe(+2) ion chelator (dipyridyl), prior to irradiation, completely protected the xthA mutant against UVB lethal lesions, suggesting the generation of toxic oxidative lesions mediated by transition metal reactions. The nfo strain displayed increased UVB-induced mutagenesis, which was significantly suppressed by pre-treatment with dipyridyl. Although xthA strain did not display increased mutagenesis after UVC and UVB treatments, this phenotype was not related to xthA mutation, but rather to an unknown secondary mutation specifying an antimutator phenotype. After UVB irradiation, the base substitution spectra of nfo strain revealed a bias towards AT-->GC transitions and GC-->CG transversions, which were also suppressed by previous treatment with the iron chelator. Overall, on the basis of the differential sensitivities and mutational spectra displayed after UVC and UVB treatments, we propose a role for Endo IV and Exo III to counteract DNA damage induced by the oxidative counterpart of UVB in E.coli.
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Reparación del ADN , Desoxirribonucleasa IV (Fago T4-Inducido)/fisiología , Escherichia coli/genética , Exodesoxirribonucleasas/fisiología , Mutagénesis , Quelantes/farmacología , ADN/química , Escherichia coli/metabolismo , Escherichia coli/efectos de la radiación , Genotipo , Hierro/química , Oxígeno/metabolismo , Fenotipo , Sensibilidad y Especificidad , Rayos UltravioletaRESUMEN
A free-ranging group of Saimiri sciureus was studied in a semi-natural forest habitat in eastern Amazonia, where behaviour patterns were broadly similar to those recorded for the species in the wild. According to focal-animal samples, the monkeys spent the vast majority of their time foraging and feeding, in particular for arthropod prey, which contributed almost half of identified food items. The predation of a small-bodied bat was also observed, although the study animals did not appear to forage systematically for chiropterans in the manner recorded for Saimiri oerstedi.