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1.
Calcif Tissue Int ; 109(1): 104-109, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33616713

RESUMEN

Hepatitis C-associated osteosclerosis (HCAO) remains a rare condition despite the growing prevalence of hepatitis C virus (HCV) infection worldwide. Since the first case reported in 1992, this is the twenty-second case described. Patients with HCAO present with severe bone pain and elevated serum levels of bone markers, especially alkaline phosphatase (ALP), with increased bone density. We report here the case of a 59-year-old man with generalized bone pain and diagnosis of HCV infection. Biochemical tests showed elevated bone turnover markers, specifically, ALP, carboxy-terminal collagen crosslinks and osteocalcin. Imaging studies revealed generalized bone sclerosis. Bone mineral density was elevated in all validated sites. His clinical symptoms and bone-related findings were attributed to HCAO. He was sequentially treated with cholecalciferol, prednisone, sofosbuvir associated with daclatasvir and ibandronate, and progressed with undetectable viral load after HCV treatment, normalization of ALP levels after introduction of ibandronate, and pain improvement 1 year after discontinuation of the bisphosphonate. Bone pain complaints must be investigated in patients with HCV. HCAO is a differential diagnosis of increased bone mass.


Asunto(s)
Hepatitis C Crónica , Hepatitis C , Osteosclerosis , Carbamatos , Hepacivirus , Hepatitis C/complicaciones , Hepatitis C/tratamiento farmacológico , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Ácido Ibandrónico , Imidazoles , Masculino , Persona de Mediana Edad , Osteosclerosis/tratamiento farmacológico , Pirrolidinas , Sofosbuvir , Valina/análogos & derivados
2.
Ecotoxicol Environ Saf ; 189: 109991, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31780208

RESUMEN

The honey bee Apis mellifera is an important pollinator of agricultural crops and natural forests. Honey bee populations have declined over the years, as a result of diseases, pesticides, and management problems. Fungicides are the main pesticides found in pollen grains, which are the major source of protein for bees. The objective of this study was to evaluate the cytotoxic effects of the fungicide iprodione on midgut cells of adult A. mellifera workers. Bees were fed on iprodione (LD50, determined by the manufacturer) for 12 or 24 h, and the midgut was examined using light and transmission electron microscopies. The expression level of the autophagy gene atg1 was assessed in midgut digestive cells. Cells of treated bees had signs of apoptosis: cytoplasmic vacuolization, apical cell protrusions, nuclear fragmentation, and chromatin condensation. Ultrastructural analysis revealed some cells undergoing autophagy and necrosis. Expression of atg1 was similar between treated and control bees, which can be explained by the facts that digestive cells had autolysosomes, whereas ATG-1 is found in the initial phases of autophagy. Iprodione acts by inhibiting the synthesis of glutathione, leading to the generation of reactive oxygen species, which in turn can induce different types of cell death. The results indicate that iprodione must be used with caution because it has side effects on non-target organisms, such as pollinator bees.


Asunto(s)
Aminoimidazol Carboxamida/análogos & derivados , Abejas/efectos de los fármacos , Fungicidas Industriales/toxicidad , Hidantoínas/toxicidad , Aminoimidazol Carboxamida/toxicidad , Animales , Apoptosis/efectos de los fármacos , Abejas/citología , Sistema Digestivo/citología , Sistema Digestivo/efectos de los fármacos , Plaguicidas/análisis , Polen/química
3.
Microsc Microanal ; 26(6): 1236-1244, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32924896

RESUMEN

The carpenter ant Camponotus rufipes has intracellular bacteria in bacteriocytes scattered in the midgut epithelium, which have different amounts of endosymbionts, according to the developmental stages. However, there are no detailed data about the midgut cells in adult workers. The present work aimed to evaluate the morphology and cellular events that coordinate the abundance of endosymbionts in the midgut cells in C. rufipes workers. The midgut epithelium has digestive cells, bacteriocytes, and cells with intermediate morphology. The latter is similar to bacteriocytes, due to the abundance of endosymbionts, and similar to digestive cells, due to their microvilli. The digestive and intermediate cells are rich in autophagosomes and autolysosomes, both with bacteria debris in the lumen. These findings suggest that midgut cells of C. rufipes control the endosymbiont level by the autophagy pathway.


Asunto(s)
Hormigas , Animales , Autofagia , Bacterias , Humanos , Simbiosis
4.
Ecotoxicol Environ Saf ; 167: 69-75, 2019 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-30296698

RESUMEN

The selectivity of insecticides on natural enemies in pest control are an important strategy for Integrated Pest Management. However, insecticides can have side effects on non-target organisms such as natural enemies. This study evaluated the histological and cytological changes mediated by the sublethal concentration of the imidacloprid insecticide on the midgut of non-target predator Podisus nigrispinus (Heteroptera: Pentatomidae), used in the biological control of pests. Imidacloprid was toxic for P. nigrispinus with LC50 = 3.75 mg L-1 and survival of 51.8%. This sublethal concentration of imidacloprid causes histological alterations in the midgut epithelium and cytotoxic features were irregular border epithelium, cytoplasmic vacuolation, and apocrine secretions in the first 6 h after exposure with the insecticide. Apoptosis in the digestive cells occurs after 12 h of exposure in the midgut. These results suggest that imidacloprid may affect the digestive physiology of P. nigrispinus and compromise the effective predation of this insect a biological control agent. The associated use of this insecticide with the predator in pest control should be carefully evaluated.


Asunto(s)
Tracto Gastrointestinal/efectos de los fármacos , Heterópteros/efectos de los fármacos , Insecticidas/toxicidad , Neonicotinoides/toxicidad , Nitrocompuestos/toxicidad , Animales , Agentes de Control Biológico , Tracto Gastrointestinal/metabolismo , Heterópteros/metabolismo , Dosificación Letal Mediana , Conducta Predatoria/efectos de los fármacos , Pruebas de Toxicidad
5.
Ecotoxicol Environ Saf ; 175: 148-154, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-30897413

RESUMEN

Populations of stingless bees have declined around the world and pesticides have been indicated as one of the possible causes of this decrease. Spinosad, which is synthesized from the fermentation process produced by the soil actinomycete Saccharopolyspora spinosa, is one of the most used bioinsecticides today. This study aimed to evaluate the possible effects of spinosad (formulation) on survival, general group activity and the processes of autophagy, apoptosis and oxidative stress in two organs (midgut and brain) of workers of Partamona helleri, after 24 h of oral exposure. Workers were orally exposed to different concentrations of spinosad. The concentration (8.16 × 10-3 mg a.i./mL) that led to the mortality of approximately half the number of treated bees was considered LC50 and was used in behavior, histology and immunofluorescence bioassays. The results revealed that bee survival was substantially reduced with increasing spinosad concentrations. The LC50 of the bioinsecticide compromised general group activity, caused morphological alterations in the midgut and intensified the processes of autophagy, apoptosis and oxidative stress in this organ. The brain, on the other hand, did not present significant alterations under the tested conditions. The data obtained demonstrate, therefore, that spinosad negatively affects individual survival, general group activity and the midgut epithelium of P. helleri.


Asunto(s)
Abejas/efectos de los fármacos , Conducta Animal/efectos de los fármacos , Sistema Digestivo/efectos de los fármacos , Insecticidas/efectos adversos , Macrólidos/efectos adversos , Animales , Abejas/crecimiento & desarrollo , Encéfalo/efectos de los fármacos , Combinación de Medicamentos , Himenópteros , Dosificación Letal Mediana
6.
Dev Biol ; 431(2): 194-204, 2017 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-28939335

RESUMEN

In insects, the hindgut is a homeostatic region of the digestive tract, divided into pylorus, ileum, and rectum, that reabsorbs water, ions, and small molecules produced during hemolymph filtration. The hindgut anatomy in bee larvae is different from that of adult workers. This study reports the morphological changes and cellular events that occur in the hindgut during the metamorphosis of the honeybee Apis mellifera. We describe the occurrence of autophagosomes and the ultrastructure of the epithelial cells and cuticle, suggesting that cuticular degradation begins in prepupae, with the cuticle being reabsorbed and recycled by autophagosomes in white- and pink-eyed pupae, followed by the deposition of new cuticle in light-brown-eyed pupae. In L5S larvae and prepupae, the hindgut undergoes cell proliferation in the anterior and posterior ends. In the pupae, the pylorus, ileum, and rectum regions are differentiated, and cell proliferation ceases in dark-brown-eyed pupae. Apoptosis occurs in the hindgut from the L5S larval to the pink-eyed pupal stage. In light-brown- and dark-brown-eyed pupae, the ileum epithelium changes from pseudostratified to simple only after the production of the basal lamina, whereas the rectal epithelium is always flattened. In black-eyed pupae, ileum epithelial cells have large vacuoles and subcuticular spaces, while in adult forager workers these cells have long invaginations in the cell apex and many mitochondria, indicating a role in the transport of compounds. Our findings show that hindgut morphogenesis is a dynamic process, with tissue remodeling and cellular events taking place for the formation of different regions of the organ, the reconstruction of a new cuticle, and the remodeling of visceral muscles.


Asunto(s)
Apoptosis , Abejas/anatomía & histología , Abejas/embriología , Sistema Digestivo/citología , Sistema Digestivo/embriología , Jerarquia Social , Integumento Común/anatomía & histología , Animales , Autofagia , Abejas/ultraestructura , Caspasa 3/metabolismo , Proliferación Celular , Sistema Digestivo/ultraestructura , Histonas/metabolismo , Larva/citología , Larva/ultraestructura , Pupa/citología , Pupa/ultraestructura
7.
Ecotoxicol Environ Saf ; 156: 1-8, 2018 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-29524778

RESUMEN

Annonaceous acetogenins (Annona squamosa Linnaeus) comprises of a series of natural products which are extracted from Annonaceae species, squamocin proved to be highly efficient among those agents. Squamocin is mostly referred as a lethal agent for midgut cells of different insects, with toxic effects when tested against larva of some insects. In present study, LC50 and LC90 of squamocin for A. gemmatalis Hübner (Lepidoptera: Noctuidae) were calculated using probit analysis. Morphological changes in midgut cells were analyzed under light, fluorescence and transmission electron microscopes when larvae were treated with LC50 and LC90 of squamocin for 24, 48 and 72 h. Results revealed that the maximum damage to midgut cells was found under LC90 where it showed digestive cells with enlarged basal labyrinth, highly vacuolated cytoplasm, damaged apical surface, cell protrusions to the gut lumen, autophagy and cell death. The midgut goblet cells showed a strong disorganization of their microvilli. Likewise, in insects treated with squamocin, mitochondria were not marked with Mitotracker fluorescent probe, suggesting some molecular damage in these organelles, which was reinforced by decrease in the respiration rate in these insects. These results demonstrate that squamocin has potential to induce enough morphological changes in midgut through epithelial cell damage in A. gemmatalis.


Asunto(s)
Furanos/toxicidad , Lactonas/toxicidad , Lepidópteros/efectos de los fármacos , Animales , Autofagia , Sistema Digestivo/anatomía & histología , Sistema Digestivo/efectos de los fármacos , Sistema Digestivo/ultraestructura , Larva/anatomía & histología , Larva/efectos de los fármacos , Larva/ultraestructura , Lepidópteros/anatomía & histología , Lepidópteros/crecimiento & desarrollo , Lepidópteros/ultraestructura
8.
Reprod Domest Anim ; 53(5): 1103-1113, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29893035

RESUMEN

The growth hormone (GH) and growth insulin-like factor-1 (IGF-1) act directly upon the regulation and growth in the different phases of preantral follicles. Thus, it is necessary to define their sequentiality until the in vitro preovulatory development. Therefore, the study aimed to assess the effects of a sequential medium containing GH and/or IGF-1 in the long-duration in vitro culture of preantral ovarian follicles. Ovarian fragments were cultivated: first half (days 1-7), second half (days 7-14) or during 14 culture days. Treatments were identified as: αMEM+; GH â†’ IGF-1; IGF-1 â†’ GH and GH + IGF-1. The culture was designed in 24-well plates, in an incubator at 37°C and 5% CO2 . The parameters of normality, viability, follicles (primordial/in developing) and follicle diameter were evaluated. In addition, the ultrastructure was confirmed with electron transmission microscopy. The results showed that the culture treated with GH â†’ IGF-1 kept the follicular normality and the viability until the 14th day of culture and increased both in the follicular development until 7th day and in the follicular diameter until 14th day, when compared to the control. The treatments IGF-1 â†’ GH and GH + IGF-1 were not effective in the developing and follicular diameter after 7 days of culture, and also reduced the percentage of viability. It is concluded that the bovine preantral follicles cultured in the sequential medium treated with GH â†’ IGF-1 improved the follicular development until the first half of the culture and kept these parameters with normality, viability and ultrastructure until the second half of the in vitro culture.


Asunto(s)
Hormona del Crecimiento/farmacología , Factor I del Crecimiento Similar a la Insulina/farmacología , Oocitos/fisiología , Folículo Ovárico/fisiología , Animales , Bovinos , Femenino , Oocitos/efectos de los fármacos , Folículo Ovárico/efectos de los fármacos , Técnicas de Cultivo de Tejidos/veterinaria
9.
Parasitology ; 144(7): 904-916, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28134069

RESUMEN

We compared the relevance of ibuprofen, vitamins C and E to control oxidative/nitrosative stress and heart disease in mice infected by Trypanosoma cruzi. Swiss mice were randomized into five groups: control, uninfected; infected without treatment; and infected treated with vitamins C, E or ibuprofen. Animals were inoculated with 2000 trypomastigote forms of T. cruzi. After 20 days, infected mice presented reduced vitamin C and E tissue levels, high cytokines (interferon gamma, tumour necrosis factor-α, interleukin 10 and chemokine ligand 2), prostaglandin F2α (PGF2α ) and nitric oxide (NO) cardiac production, intense myocarditis and reactive tissue damage, which was directly correlated with the intensity of the inflammatory infiltrate and the degree of pathological cardiac remodelling. Vitamins C and E supplementation were irrelevant to counteract reactive tissue damage and myocarditis in infected animals. Conversely, ibuprofen reduced tissue levels of cytokines, PGF2α and NO, as well as lipid and protein oxidation, antioxidant enzyme activity and the cardiac damage, without interfering with heart parasitism. Our results do not support the applicability of vitamin C and E supplementation in the management of acute Chagas cardiomyopathy. By controlling the inflammatory infiltrate, anti-inflammatory-based therapy proved to be a more rational strategy than a direct antioxidant therapy in attenuating oxidative/nitrosative stress and cardiac damage.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Antioxidantes/uso terapéutico , Enfermedad de Chagas/tratamiento farmacológico , Animales , Antiinflamatorios no Esteroideos/farmacología , Antioxidantes/farmacología , Enfermedad de Chagas/inmunología , Enfermedad de Chagas/parasitología , Modelos Animales de Enfermedad , Masculino , Ratones , Estrés Nitrosativo , Trypanosoma cruzi/efectos de los fármacos
10.
Int J Gynecol Pathol ; 33(3): 225-34, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24681731

RESUMEN

We hypothesized that the activation of cyclooxygenase (COX)-2, epidermal growth factor receptor (EGFR), and ErbB-2 signaling is required for cervical intraepithelial neoplasia (CIN) lesions to progress to cervical cancer. A retrospective analysis was performed in 179 patients with Stage I squamous cell carcinoma (SCC) and 233 patients with CIN (112 CIN I, 47 CIN II, and 74 CIN III). COX-2, EGFR, and ErbB-2 expression was analyzed by immunohistochemistry using the ACIS III automated imaging system. The mean expression of COX-2, EGFR, and ErbB-2 was compared between the various stages of CIN and SCC. COX-2 mean expression was predominantly cytoplasmic, increasing significantly from CIN I to CIN II, CIN III, and SCC (P<0.001). EGFR mean expression also rose significantly during tumor progression from CIN I to SCC (P=0.001). CIN I samples were negative for ErbB-2 expression. CIN II, CIN III, and SCC were considered positive for ErbB-2 expression in 2.2%, 14%, and 16.2% of cases, respectively. There was also a statistically significant correlation between increase of ErbB-2 positivity from CIN to SCC. We conclude that COX-2, EGFR, and ErbB-2 expression increase significantly during the progression of CIN to cancer.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/patología , Infecciones por Papillomavirus/patología , Lesiones Precancerosas/patología , Displasia del Cuello del Útero/patología , Neoplasias del Cuello Uterino/patología , Automatización de Laboratorios , Ciclooxigenasa 2/metabolismo , Progresión de la Enfermedad , Receptores ErbB/metabolismo , Femenino , Humanos , Infecciones por Papillomavirus/metabolismo , Receptor ErbB-2/metabolismo , Estudios Retrospectivos , Análisis de Matrices Tisulares , Neoplasias del Cuello Uterino/metabolismo , Displasia del Cuello del Útero/metabolismo
11.
Microsc Microanal ; 20(1): 285-95, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24188829

RESUMEN

Bumblebees need to keep bodily homeostasis and for that have an efficient system of excretion formed by the Malpighian tubules, ileum, and rectum. We analyzed the excretory organs of Bombus morio, a bee without rectal pads. In addition, we analyzed the rectal epithelium of Melipona quadrifasciata anthidioides which has rectal pads. The Malpighian tubules exhibited two cell types and the ileum four types. However, comparative analysis of the rectum showed that only cells of the anterior region of the rectal epithelium of B. morio are structurally distinct. We suggest that cells of the Malpighian tubules of B. morio have an excretory feature and that cells of ileum have different functions, such as ion absorption and water, organic compound, and protein secretion. In addition, only the anterior region of the rectum of B. morio showed characteristic absorption. We suggest that Malpighian tubules participate in the excretion of solutes and that the ileum and rectal epithelium are responsible for homeostasis of water and solutes, compensating for the absence of rectal papillae. These results contribute to our understanding of the morphophysiology of the excretory organs of bees without rectal pads.


Asunto(s)
Abejas/ultraestructura , Túbulos de Malpighi/ultraestructura , Recto/ultraestructura , Animales , Íleon/ultraestructura , Microscopía Electrónica
12.
Sci Total Environ ; 815: 152847, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-34995599

RESUMEN

The honey bee Apis mellifera is an important pollinator that increases the yield and quality of crops. In recent years, honey bee populations have declined in some parts of the world, which has been associated with several causes, including pesticides used in agriculture. Neonicotinoids are neurotoxic insecticides widely used in the world with systemic action mode contaminating nectar and pollen that may be consumed by bees. This study evaluated the side effects of imidacloprid in the midgut of A. mellifera after acute oral exposure. Toxicity, histopathology, cytotoxicity, and expression of autophagy-related gene atg1 were evaluated in honey bee workers orally exposed to imidacloprid. The estimated imidacloprid LC50 was 1.44 mg L-1. The midgut epithelium of bees fed on imidacloprid LC50 has the occurrence of cytoplasm vacuoles, enlarged intercellular spaces, disorganization of the striated border, and nuclear pyknosis, with an organ injury index that increases with time exposure. The midgut digestive cells of treated bees have apical protrusions, damaged mitochondria, and autophagosomes that were characterized for content with organelle debris and high expression of atg1. These features indicate the occurrence of high cell death in the midgut of workers exposed to imidacloprid, which may affect the digestibility the physiology of the insect.


Asunto(s)
Insecticidas , Nitrocompuestos , Animales , Apoptosis , Autofagia , Abejas , Insecticidas/toxicidad , Neonicotinoides/toxicidad , Nitrocompuestos/toxicidad
13.
Rev Bras Ginecol Obstet ; 42(10): 642-648, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33129220

RESUMEN

OBJECTIVE: To evaluate the agreement between the histopathological diagnoses of preoperative endometrial samples and surgical specimens and correlate the agreement between the diagnoses with the impact on surgical management and the survival of patients with endometrial adenocarcinomas. METHODS: Sixty-two patients treated for endometrial cancer at a university hospital from 2002 to 2011 were retrospectively evaluated. The histopathological findings of preoperative endometrial samples and of surgical specimens were analyzed. The patients were subjected to hysterectomy as well as adjuvant treatment, if necessary, and clinical follow-up, according to the institutional protocol. Lesions were classified as endometrioid tumor (type 1) grades 1, 2, or 3 or non-endometrioid carcinoma (type 2). RESULTS: The agreement between the histopathological diagnoses based on preoperative endometrial samples and surgical specimens was fair (Kappa: 0.40; p < 0.001). However, the agreement was very significant for tumor type and grade, in which a higher concordance occurred at a higher grade. The percentage of patients with lymph nodes affected was 19.2%. Although most patients presenting with disease remission or cure were in the early stages (90.5%), there were no significant differences between those patients who had a misdiagnosis (11/16; 68.8%) and those who had a correct diagnosis (25/33; 75.8%) based on preoperative endometrial sampling (p = 0.605). CONCLUSION: Our findings corroborate the literature and confirm the under staging of preoperative endometrial samples based on histopathological assessment, especially for lower grade endometrial tumors. We suggest that the preoperative diagnosis should be complemented with other methods to better plan the surgical management strategy.


OBJETIVO: Avaliar a concordância entre os diagnósticos histopatológicos de amostras endometriais pré-operatórias e cirúrgicas de pacientes com adenocarcinomas endometriais e avaliar o impacto da concordância entre os diagnósticos no planejamento cirúrgico e sobrevida das pacientes. MéTODOS: Dados de 62 pacientes com câncer de endométrio operadas entre 2002 a 2011 em um hospital universitário foram avaliadas retrospectivamente. As pacientes foram submetidas à histerectomia e tratamento adjuvante, se necessário, e acompanhadas clinicamente de acordo com o protocolo institucional. Foram avaliados os resultados das análises histopatológicas das amostras endometriais pré-operatórias e cirúrgicas. As lesões foram classificadas como tumor endometrioide (tipo 1) graus 1, 2 ou 3 ou carcinoma não endometrioide (tipo 2). RESULTADOS: De modo geral, houve uma concordância baixa entre os diagnósticos histopatológicos das amostras endometriais pré-operatórias e cirúrgicas (Kappa: 0,40; p < 0,001). Entretanto, uma alta concordância entre os diagnósticos foi observada nos tumores de graus mais elevados. Comprometimento de linfonodos ocorreu em 19,2% das pacientes e a maioria das que apresentaram remissão ou cura foram diagnosticadas nos estágios iniciais da doença (90,5%). Não houve diferença significativa na taxa de remissão ou cura entre as pacientes que tiveram concordância (25/33; 75,8%) ou divergência (11/16; 68,8%) entre os resultados histopatológicos pré-operatórios e cirúrgicos (p = 0,605). CONCLUSãO: Nossos achados corroboram a literatura e confirmam o sub-estadiamento de amostras endometriais pré-operatórias com base na avaliação histopatológica, especialmente para tumores endometriais de baixo grau. Outros métodos complementares são necessários para um diagnóstico pré-operatório mais preciso a fim de melhorar o planejamento cirúrgico.


Asunto(s)
Adenocarcinoma/patología , Neoplasias Endometriales/patología , Adulto , Anciano , Brasil/epidemiología , Estudios de Cohortes , Estudios Transversales , Neoplasias Endometriales/mortalidad , Femenino , Humanos , Histerectomía , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Patología Quirúrgica , Valor Predictivo de las Pruebas , Periodo Preoperatorio , Estudios Retrospectivos , Análisis de Supervivencia
14.
Oncol Rep ; 21(2): 313-20, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19148501

RESUMEN

The Wnt family is involved in tumorigenesis of several tissues. In ovarian cancer, the role played by Wnts and its pathways is not clearly defined. In order to analyze the canonical and noncanonical Wnt pathway in normal ovary, benign ovarian tumor and ovarian cancer, we evaluated the immunohistochemical expression of Wnt1, Frizzled-1 (FZD1), Wnt5a, Frizzled-5 (FZD5) and beta-catenin. Ovarian specimens were obtained from surgeries performed between 1993 and 2004. The patients were divided in three groups: group A, epithelial ovarian cancer (n=38); group B, benign epithelial neoplasia (n=28); and group C, normal ovaries (n=26). Immunoreactivity for Wnt1, FZD1, Wnt5a, FZD5 and beta-catenin was scored for each group. The proportion of Wnt1 positive women in group A (29.4%) was significantly higher than in group B (4.3%) and C (9.1%) (p=0.020). The proportion of FZD1 positive patients in group C (54.5%) was significantly lower than in group A (97.1%) and B (90.0%) (p<0.001). The proportion of Wnt5a positive women was significantly higher for group A (80.0%) compared to group B (25.0%) and C (27.3%) (p<0.001). The proportion of beta-catenin positive patients in group C (95.8%) was significantly higher than group B (52.4%) (p=0.004). Comparison of the survival curves in group A according to Wnt5a expression showed a significant difference between positive and negative patients, whereas the Wnt5a positive women showed worse results (p=0.050). Our findings suggest that the pathways related to Wnt5a have an important role in ovarian malignant neoplasia. Furthermore, Wnt5a was found to be a predictor of poor prognosis for ovarian cancer.


Asunto(s)
Biomarcadores de Tumor/análisis , Receptores Frizzled/biosíntesis , Neoplasias Glandulares y Epiteliales/metabolismo , Neoplasias Ováricas/metabolismo , Proteínas Wnt/biosíntesis , beta Catenina/biosíntesis , Femenino , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Estadificación de Neoplasias , Neoplasias Glandulares y Epiteliales/patología , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/patología , Ovario , Pronóstico , Transducción de Señal/fisiología
15.
Microsc Res Tech ; 82(6): 941-948, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30901503

RESUMEN

The ant Paraponera clavata (Fabricius, 1775) is the only extant species of Paraponerinae and is widely distributed in Brazilian forests. Aspects of its biology are documented extensively in the literature; however, knowledge of P. clavata internal morphology, specifically of exocrine glands, is restricted to the venom apparatus. The objective of this study was to describe the mandibular gland morphology of P. clavata workers. The mandibular gland is composed of a reservoir connected to a cluster of Type III secretory cells with cytoplasm rich in mitochondria and lipid droplets, similar to that of other ants. Notably, the glandular secretion is rich in protein and has a solid aspect. This is the first morphological description of the mandibular gland of P. clavata. RESEARCH HIGHLIGHTS: This study presents the morphological description of the mandibular gland of Paraponera clavata (Hymenoptera: Paraponerinae). Singular characteristics of the gland are described: the glandular secretion is rich in protein and has a solid aspect.


Asunto(s)
Hormigas/anatomía & histología , Glándulas Salivales/anatomía & histología , Animales , Hormigas/citología , Hormigas/ultraestructura , Brasil , Histocitoquímica , Microscopía , Microscopía Electrónica de Transmisión
16.
Arthropod Struct Dev ; 53: 100885, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31614307

RESUMEN

The permeability of the peritrophic matrix, essential for its function, depends on its chemical composition. The objective was to determine if the permeability of the peritrophic matrix varies along the midgut and in the presence of anti-peritrophin-55 antibody in Melipona quadrifasciata and Apis mellifera bees. The thickness of the peritrophic matrix in both species varies between the anterior and posterior midgut regions in workers. In A. mellifera dextran molecules with 40 kDa cross the peritrophic matrix, whereas those ≥70 kDa are retained in the endoperitrophic space. In M. quadrifasciata the peritrophic matrix permeability was for molecules <40 kDa. Bees fed on anti-peritrophin-55 antibody showed an increase in peritrophic matrix permeability, but survival was not affected. In the bees studied, the peritrophic matrices have morphological differences between midgut regions, but there is no difference in their permeability along the midgut, which is affected by peritrophin 55.


Asunto(s)
Abejas/fisiología , Proteínas de Insectos/metabolismo , Glicoproteínas de Membrana/metabolismo , Animales , Fenómenos Fisiológicos del Sistema Digestivo , Inmunohistoquímica , Permeabilidad , Especificidad de la Especie
17.
Chemosphere ; 221: 464-470, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30654260

RESUMEN

The mosquito Aedes aegypti is the main vector of Dengue, Chikungunya, Zika, and yellow fever viruses, which are responsible for high human morbidity and mortality. The fight against these pathogens is mainly based on the control of the insect vector with the use of insecticides. Among insecticides, spinosad bioinsecticide is efficient against A. aegypti larvae and may be an alternative for vector control. Here, we investigate the sublethal effects of spinosad during midgut metamorphosis of A. aegypti females and its cumulative effects on blood acquisition capacity and fecundity in adults. We studied the midgut because it is an important model organ directly related to blood acquisition and digestion. Treatment of larvae with spinosad induced oxidative stress, apoptosis, and damage to the midgut cells at all stages of development and in adults. There was a reduction in the number of proliferating cells and the number of enteroendocrine cells in treated individuals. In addition, damage caused by spinosad led to a reduction in oviposition and egg viability of A. aegypti females. Finally, the exposure of mosquito larvae to sublethal concentrations of spinosad interfered with the development of the midgut, arresting the blood digestion and reproduction of adult females with blood digestion and reproduction difficulties.


Asunto(s)
Aedes/efectos de los fármacos , Insecticidas , Larva/efectos de los fármacos , Macrólidos/farmacología , Animales , Combinación de Medicamentos , Femenino , Fertilidad/efectos de los fármacos , Humanos , Insecticidas/farmacología , Mosquitos Vectores , Virosis/prevención & control
18.
Insects ; 10(3)2019 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-30875839

RESUMEN

Friesella schrottkyi is a small stingless bee (3-mm long) important for agricultural and native forest pollination. This study describes the morphology and morphometry of the midgut in F. schrottkyi forager workers. The F. schrottkyi midgut presents a single-layered epithelium with digestive, regenerative and endocrine cells. The digestive cells are similar along the entire midgut length with a spherical nucleus, apex with long striated border, cytoplasmic granules in the apical region and well-developed basal labyrinth associated with mitochondria, suggesting they are multifunctional, synthesizing digestive enzymes and peritrophic matrix compounds and absorbing nutrients. Regenerative cells are located around the basal region organized in nests with some cells with a spherical nucleus. Phe-Met-Arg-Phe-NH2-amide (FMRFamide) positive endocrine cells are restricted to the posterior midgut region, suggesting a paracrine function in the midgut. This is the first morphological description of the F. schrottkyi midgut contributing to the comprehension of the digestive process of this bee.

19.
PeerJ ; 7: e7489, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31534837

RESUMEN

Juvenile hormone analogs (JHA) are known to interfere with growth and biosynthesis of insects with potential for insecticide action. However, there has been comparatively few data on morphological effects of JHA on insect organs. To determine pyriproxyfen effects on Aedes aegypti larvae, we conducted toxicity, behavioral bioassays and assessed ultrastructural effects of pyriproxyfen on midgut cells. A. aegypti larvae were exposed in aqueous solution of pyriproxyfen LC50 concentrations and evaluated for 24 h. This study fulfilled the toxic prevalence of pyriproxyfen to A. aegypti larvae (LC50 = 8.2 mg L-1). Behavioral observations confirmed that pyriproxyfen treatment significantly changes swimming behavior of larvae, limiting its displacement and speed. The pyriproxyfen causes remarkable histopathological and cytotoxic alterations in the midgut of larvae. Histopathological study reveals presence of cytoplasmic vacuolization and damage to brush border of the digestive cells. The main salient lesions of cytotoxic effects are occurrence of cell debris released into the midgut lumen, cytoplasm rich in lipid droplets, autophagosomes, disorganized microvilli and deformed mitochondria. Data suggest that pyriproxyfen can be used to help to control and eradicate this insect vector.

20.
Mol Genet Genomic Med ; 7(12): e962, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31595705

RESUMEN

BACKGROUND: Maturity-onset diabetes of the young (MODY) is a form of monogenic diabetes with autosomal dominant inheritance. To date, mutations in 11 genes have been frequently associated with this phenotype. In Brazil, few cohorts have been screened for MODY, all using a candidate gene approach, with a high prevalence of undiagnosed cases (MODY-X). METHODS: We conducted a next-generation sequencing target panel (tNGS) study to investigate, for the first time, a Brazilian cohort of MODY patients with a negative prior genetic analysis. One hundred and two patients were selected, of which 26 had an initial clinical suspicion of MODY-GCK and 76 were non-GCK MODY. RESULTS: After excluding all benign and likely benign variants and variants of uncertain significance, we were able to assign a genetic cause for 12.7% (13/102) of the probands. Three rare MODY subtypes were identified (PDX1/NEUROD1/ABCC8), and eight variants had not been previously described/mapped in genomic databases. Important clinical findings were evidenced in some cases after genetic diagnosis, such as MODY-PDX1/HNF1B. CONCLUSION: A multiloci genetic approach allowed the identification of rare MODY subtypes, reducing the large percentage of MODY-X in Brazilian cases and contributing to a better clinical, therapeutic, and prognostic characterization of these rare phenotypes.


Asunto(s)
Diabetes Mellitus Tipo 2/genética , Pruebas Genéticas/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Adolescente , Adulto , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Brasil , Estudios de Cohortes , Femenino , Predisposición Genética a la Enfermedad , Proteínas de Homeodominio/genética , Humanos , Masculino , Análisis de Secuencia de ADN , Receptores de Sulfonilureas/genética , Transactivadores/genética , Adulto Joven
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