Comparative morphology of the midgut of three species of Cephalotes (Hymenoptera, Formicidae, Myrmicinae)

Studies of histological nature, histochemistry and ultra-morphology of the midgut of three species of ants belonging to the genus Cephalotes (atratus, clypeatus and pusillus) were performed. In histology H-E was employed, and in histochemistry techniques for detection of carbohydrates, proteins in general and collagen and calcium fibers were used. The results obtained from this second technique made possible some discussion about the pH of the midgut of these insects. The species are identical in the characters under study. The digestive cells exhibited a secretion that is typical of ants, the apocrine type.

Apoptosis in different gastric lesions and gastric cancer: Relationship with Helicobacter pylori, overexpression of p53 and aneuploidy

Apoptosis has an essential function in maintaining the integrity of the gastrointestinal mucosa. Its deregulation is associated with the occurrence of lesions such as in atrophic gastritis, peptic ulcers, intestinal metaplasia, and stomach tumorigenesis. Thus, the aim of the present study was to investigate the frequency of apoptotic cells (apoptotic index, AI) by using two different immunohistochemical techniques, TUNEL and anti-activated caspase-3 antibody (CPP32), in gastric dyspepsia [chronic gastritis (CG, N = 34), chronic atrophic gastritis (CAG, N = 11), gastric ulcer (GU, N = 17), and intestinal metaplasia (IM, N = 15)], normal gastric mucosae (NM, N = 8), and gastric adenocarcinoma (GC, N = 12). The relationship was investigated between the AI and Helicobacter pylori infection, diagnosed by PCR, overexpression of p53 protein determined by immunohistochemistry, and aneuploidy by fluorescence in situ hybridization, as performed by our laboratory in previous studies. No significant differences were observed in AI between the different groups, whether by the TUNEL technique (F = 1.60; P = 0.1670) or by CPP32 antibody (F = 1.70; P = 0.1420). Nonetheless, CAG and CG groups had AI statistically higher than those of normal mucosae. These two groups (CAG and CG) also showed a higher frequency of apoptosis-positive cases (TUNEL+ or CPP32+). Generally, there was no correlation between the AI detected by the TUNEL and CPP32 techniques in the groups studied, except in the GC group (r = 0.70). Moreover, there was no significant association between apoptosis and H. pylori infection, overexpression of p53 protein and aneuploidy, but the H. pylori-positive cases only of GU (P = 0.0233) and IM (P = 0.0253) groups displayed a statistically higher AI compared to H. pylori-negative NM, when the CPP32 antibody technique was used. Thus, CG and CAG have increased apoptosis, which may occur independent of an association with H. pylori infection, aneuploidy and overexpression of p53 protein. ©FUNPEC-RP.

Prolapso de glândula de terceira pálpebra em cäes: Avaliação cito e histopatológica

The present experiment was carried out in ten animals with third eyelid prolapsed gland. All of the prolapsed glands were surgically excised. The age of the dogs ranged from two month to ten years old, and the breeds were Beagle (20%), Teckel (10%), Pinscher (10%), Poodle (10%) and other mongrel dogs. Aspirative citology was made in all the removed glands, after that they were fixed in 10% formalin and stained with Hematoxiline and Eosine. It was observed a focal mononuclear inflamatory infiltrate in the conjunctive and periacinal tissues. Ductal dilatation and metaplasia were noted on cells of the ducts. Cyitologic examination showed similar inflamatory infiltrate to histopatologic findings. The glands showed a chronic adenitis. The absence of histo and cytologic significance changes justify the tissue function observed during surgical excision.

Avaliação histeroscópica em pacientes com infertilidade

PURPOSE: to describe hysteroscopy findings in infertile patients. METHODS: this was a retrospective series of 953 patients with diagnosis of infertility evaluated by hysteroscopy. A total of 957 patients investigated for infertility were subjected to hysteroscopy, preferentially during the first phase of the menstrual cycle. When necessary, directed biopsies (under direct visualization during the exam) or guided biopsies were obtained using a Novak curette after defining the site to be biopsied during the hysteroscopic examination. Outcome frequencies were determined as percentages, and the χ2 test was used for the correlations. The statistical software EpiInfo 2000 (CDC) was used for data analysis. RESULTS: a normal uterine cavity was detected in 436 cases (45.8%). This was the most frequent diagnosis for women with primary infertility and for women with one or no abortion (p<0.05). Abnormal findings were obtained in 517 of 953 cases (54.2%), including intrauterine synechiae in 185 patients (19.4%), endometrial polyps in 115 (12.1%), endocervical polyps in 66 (6.0%), submucosal myomas in 47 (4.9%), endometrial hyperplasia in 39 (4.1%), adenomyosis in five (0.5%), endometritis (with histopathological confirmation) in four (0.4%), endometrial bone metaplasia in two (0.4%), and cancer of the endometrium in one case (0.1%). Morphological and functional changes of the uterus were detected in 5.6% of the cases, including uterine malformations in 32 (3.4%) and isthmus-cervical incompetence in 21 (2.2%). CONCLUSIONS: intrauterine synechiae were the most frequent abnormal findings in patients evaluated for infertility. Patients with a history of abortion and infertility should be submitted to hysteroscopy in order to rule out intrauterine synechiae as a possible cause of infertility.

Side-effects of thiamethoxam on the brain andmidgut of the africanized honeybee Apis mellifera (Hymenopptera: Apidae)

The development of agricultural activities coincides with the increased use of pesticides to control pests, which can also be harmful to nontarget insects such as bees. Thus, the goal of this work was assess the toxic effects of thiamethoxam on newly emerged worker bees of Apis mellifera (africanized honeybee-AHB). Initially, we determined that the lethal concentration 50 (LC50) of thiamethoxam was 4.28 ng a.i./μL of diet. To determine the lethal time 50 (LT50), a survival assay was conducted using diets containing sublethal doses of thiamethoxam equal to 1/10 and 1/100 of the LC50. The group of bees exposed to 1/10 of the LC50 had a 41.2% reduction of lifespan. When AHB samples were analyzed by morphological technique we found the presence of condensed cells in the mushroom bodies and optical lobes in exposed honeybees. Through Xylidine Ponceau technique, we found cells which stained more intensely in groups exposed to thiamethoxam. The digestive and regenerative cells of the midgut from exposed bees also showed morphological and histochemical alterations, like cytoplasm vacuolization, increased apocrine secretion and increased cell elimination. Thus, intoxication with a sublethal doses of thiamethoxam can cause impairment in the brain and midgut of AHB and contribute to the honeybee lifespan reduction. © 2013 Wiley Periodicals, Inc.

Absence of RKIP expression is an independent prognostic biomarker for gastric cancer patients

Gastric cancer is a leading cause of cancer-related mortality, and the presence of lymph node metastasis an important prognostic factor. Downregulation of RKIP has been associated with tumor progression and metastasis in several types of neoplasms, being currently categorized as a metastasis suppressor gene. Our aim was to determine the expression levels of RKIP in gastric tissues and to evaluate its impact in the clinical outcome of gastric carcinoma patients. RKIP expression levels were studied by immunohistochemistry in a series of gastric tissues. Overall, we analysed 222 non-neoplastic gastric tissues, 152 primary tumors and 42 lymph node metastasis samples. We observed that RKIP was highly expressed in ∼83% of non-neoplastic tissues (including normal tissue and metaplasia), was lost in ∼56% of primary tumors and in ∼90% of lymph node metastasis samples. Loss of RKIP expression was significantly associated with several markers of poor clinical outcome, including the presence of lymph node metastasis. Furthermore, the absence of RKIP protein constitutes an independent prognostic marker for these patients. In conclusion, RKIP expression is significantly lost during gastric carcinoma progression being almost absent in lymph node metastasis samples. Of note, we showed that the absence of RKIP expression is associated with poor outcome features of gastric cancer patients, this being also an independent prognostic marker.

Atrophic gastritis: Risk factor for esophageal squamous cell carcinoma in a Latin-American population

AIM: To study the association between atrophic gastritis (AG) and esophageal squamous cell carcinoma (ESCC) in a Latin-America population. METHODS: A case-control study was performed at two reference Brazilian hospitals including patients diagnosed with advanced ESCC and dyspeptic patients who had been subjected to upper gastrointestinal endoscopy, with biopsies of the gastric antrum and body. All cases with ESCC were reviewed by a single pathologist, who applied standard criteria for the diagnosis of mucosal atrophy, intestinal metaplasia, and dysplasia, all classified as AG. The data on the patients' age, sex, smoking status, and alcohol consumption were collected from clinical records, and any missing information was completed by telephone interview. The association between AG and ESCC was assessed by means of univariate and multiple conditional logistic regressions. RESULTS: Most patients were male, and the median age was 59 years (range: 37-79 years) in both the ESCC and control groups. Univariate analysis showed that an intake of ethanol greater than 32 g/d was an independent risk factor that increased the odds of ESCC 7.57 times (P = 0.014); upon multiple analysis, alcohol intake of ethanol greater than 32 g/d exhibited a risk of 4.54 (P = 0.081), as adjusted for AG and smoking. Smoking was shown to be an independent risk factor that increased the odds of ESCC 14.55 times (P = 0.011) for individuals who smoked 0 to 51 packs/year and 21.40 times (P = 0.006) for those who smoked more than 51 packs/year. Upon multiple analyses, those who smoked up to 51 packs/year exhibited a risk of 7.85 (P = 0.058), and those who smoked more than 51 packs/year had a risk 11.57 times higher (P = 0.04), as adjusted for AG and alcohol consumption. AG proved to be a risk factor that increased the odds of ESCC 5.33 times (95%CI: 1.55-18.30, P = 0.008) according to the results of univariate conditional logistic regression. CONCLUSION: There was an association by univariate conditional logistic regression between AG and ECSS in this sample of Latin-American population. © 2013 Baishideng.

Efeitos de doses subletais do imidaclopride no cérebro, ventrículo e túbulo de Malpighi de Apis melifera africanizada

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Morfologia do trato digestivo de formigas

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação do perfil de metilação e expressão do gene CDH1 em Cebus apella como modelo experimental para câncer gástrico

O câncer gástrico continua sendo uma importante causa de morte dentre os tipos de câncer no Brasil e no mundo. A origem do câncer de estomago provém, assim como nos demais, de acúmulo de alterações genéticas. Portanto, se faz necessário saber quais alterações genéticas são importantes para desencadear a patogênese do câncer gástrico. O MNU, conhecido carcinógeno, quando ingerido de forma oral em doses determinadas desencadeia o desenvolvimento de adenocarcinoma gástrico do tipo intestinal, com aparecimento de estágios pré definidos característico deste tipo tumoral. Com base nestes conhecimentos, realizamos um experimento com 6 macacos da espécie Cebus apella induzidos à desenvolver câncer gástrico do tipo intestinal. Os animais ingeriam 16mg/kg de peso diariamente da droga, com desenvolvimento de lesões pré-neoplásicas em todos. Infelizmente, devido à toxicidade da droga, somente um animal sobreviveu ao tratamento e desenvolveu desenvolveu uma massa tumoral propriamente dita. Foram feitas avaliações periódicas dos animais, em dias pré-determinados (ao início, no 120º, 150º, 300º, 940º) com coletas de fragmentos da mucosa gástrica. Foram coletadas 20 amostras de tecido, distribuídas entre mucosa normal, gastrite, displasia, metaplasia e tumoral. Destas amostras extraímos DNA para as análises do gene CDH1. Não há na literatura sequencia deste gene para a espécie utilizada no estudo. Com este objetivo, utilizamos iniciadores construídos a partir de sequencias de CDH1 de Callithrix jacchus (espécie filogeneticamente) e seqüenciamos cerca de 342pb da região promotora de CDH1 de C. apella. As análises mostraram uma similaridade de 98% desta região com a dos humanos, com presença de vários sítios de ligação de fatores de transcrição (sp1, Ap2, NF-x, AREB6, Puf e CTF) além da presença do CAAT Box. Esta região ainda possui 30 sitios CpGs, o que indica que ela pode estar sofrendo regulação epigenética. Para se verificar como se encontrava o padrão de metilação desta região realizamos uma análise de MSP com iniciadores específicos e constatamos que houve predominância de alelos não metilados de CDH1 para todas as amostras pré neoplásicas e a amostra de adenocarcinoma encontra-se metilada. O que pode ser constatado com um ensaio de Imunohistoquímica, onde somente a amostra tumoral não expressava a proteína caderina. Desta maneira nossas análises sugerem que a metilação do gene CDH1 desempenha papel importante na tumorigênese gástrica em C. apella, e é um evento tardio, uma vez que não é observado nos outro tipos teciduais não tumorais E, partindo-se da similaridade entre as seqüências, podemos sugerir que o mesmo evento pode está ocorrendo em humanos. Esta metilação do promotor do CDH1 leva a um silenciamento deste gene o que desencadeia o estabelecimento de adenocarcinomas gástricos, fato apoiado pela literatura onde vários trabalhos apontaram que a hipermetilação do promotor da caderina está associada ao desenvolvimento do câncer gástrico.

Clinical and pathological importance of vacA allele heterogeneity and cagA status in peptic ulcer disease in patients from North Brazil

We have examined the prevalence of gene cagA and vacA alleles in 129 patients, 69 with gastritis and 60 with peptic ulcer diseases from North Brazil and their relation with histopathological data. vacA and cagA genotype were determined by polymerase chain reaction. Hematoxylin-eosin staining was used for histological diagnosis. 96.6% of the patients were colonized by Helicobacter pylori strains harboring single vacA genotype (nont-mixed infection). Among them, 11.8% had subtype s1a, 67.8% had subtype s1b, and 17% subtype s2. In regard to the middle region analysis, m1 alleles were found in 75.4% and m2 in 21.2% of patients. The cagA gene was detected in 78% patients infected with H. pylori and was associated with the s1-m1 vacA genotype. The H. pylori strains, vacA s1b m1/cagA-positive, were associated with increased risk of peptic ulcer disease and higher amounts of lymphocytic and neutrophilic infiltrates and the presence of intestinal metaplasia. These findings show that cagA and vacA genotyping may have clinical relevance in Brazil.

Expressão dos antígenos ABH e Lewis na gastrite crônica e alterações pré- neoplásica da mucosa gástrica

RACIONAL: A aderência do Helicobacter pylori à mucosa gástrica humana é pré-requisito para sua colonização e o desenvolvimento da gastrite crônica. Os antígenos de grupos sangüíneos, presentes no muco gástrico, são descritos como prováveis receptores da bactéria neste epitélio. A expressão alterada destes antígenos está associada ao desenvolvimento do câncer gástrico. OBJETIVOS: Verificar a ocorrência do Helicobacter pylori e a distribuição da expressão dos antígenos ABH e Lewis correlacionada com as alterações histopatológicas de pacientes com gastrite crônica. PACIENTES E MÉTODOS: Analisaram-se 63 amostras de sangue, saliva e biopsias gástricas de pacientes com gastrite crônica através das técnicas dot-blot-ELISA, imunoperoxidase indireta e colorações do Gram modificado e hematoxilina-eosina. RESULTADOS: Não foram encontradas associações significativas entre a presença da bactéria e os fenótipos de grupos sangüíneos ABH, Lewis e Secretor. Na maioria dos pacientes, a expressão dos antígenos ABH e Lewis, estava restrita principalmente ao epitélio foveolar da mucosa gástrica, concordando com a expressão ao nível salivar. A expressão inapropriada desses antígenos ocorria sempre na infecção pelo Helicobacter pylori e/ou alterações pré-neoplásicas da mucosa gástrica. Em áreas com metaplasia intestinal foi observada a redução da reatividade para os antígenos H e Le^b, e principalmente o aumento de Le^ª. CONCLUSÃO: Alterações no padrão de glicosilação destes antígenos refletem diferentes estágios de diferenciação celular e são marcadores potenciais na avaliação diagnóstica e prognóstica das patologias gástricas.

Protective effect of gamma-tocopherol-enriched diet on N-methyl-N-nitrosourea-induced epithelial dysplasia in rat ventral prostate

Despite recent advances in understanding the biological basis ofprostate cancer (PCa), the management of this disease remains a challenge. Chemoprotective agents have been usedto protect against or eradicateprostatemalignancies. Here, we investigated the protective effect of -tocopherol on N-methyl-N-nitrosourea (MNU)-induced epithelial dysplasia in the rat ventral prostate (VP). Thirty-two male Wistar rats were divided into four groups (n=8): control (CT): healthy control animals fed a standard diet; control+-tocopherol (CT+T): healthy control animals without intervention fed a -tocopherol-enriched diet (20mg/kg); N-methyl-N-nitrosourea (MNU): rats that received a single dose of MNU (30mg/kg) plus testosterone propionate (100mg/kg) and were fed a standard diet; and MNU+-tocopherol (MNU+T): rats that received the same treatment of MNU plus testosterone and were fed with a -tocopherol-enriched diet (20mg/kg). After 4months, the VPs were excised to evaluate morphology, cell proliferation and apoptosis, as well as cyclooxygenase-2 (Cox-2), glutathione-S-transferase-pi (GST-pi) and androgen receptor (AR) protein expression, and matrix metalloproteinase-9 (MMP-9) activity. An increase in the incidence of epithelial dysplasias, such as stratified epithelial hyperplasia and squamous metaplasia, in the MNU group was accompanied by augmented cell proliferation, GST-pi and Cox-2 immunoexpression and pro-MMP-9 activity. Stromal thickening and inflammatory foci were also observed. The administration of a -tocopherol-enriched diet significantly attenuated the adverse effects of MNU in the VP. The incidence of epithelial dysplasia decreased, along with the cell proliferation index, GST-pi and Cox-2 immunoexpression. The gelatinolytic activity of pro-MMP-9 returned to the levels observed for the CT group. These results suggest that -tocopherol acts as a protective agent against MNU-induced prostatic disorders in the rat ventral prostate.

Avaliação da integração de esferas de hidroxiapatita sintética e de polietileno poroso em cavidades evisceradas de coelhos

Para a recuperação da estética facial,há necessidade de reposição do volume orbitário perdido em decorrência de eviscerações ou enucleações. Este estudo foi realizado com os objetivos de avaliar comparativamente a biocompatibilidade e a manutenção do volume orbitário com o uso de esferas de hidroxiapatita sintética e de polietileno poroso, na reconstrução de cavidades evisceradas de coelhos. Métodos: Para isso foram utilizados 56 coelhos albinos, submetidos à evisceração do olho direito, com colocação de esferas de hidroxiapatita sintética (G1 – 28 animais) ou polietileno poroso (G2 – 28 animais).Quatro coelhos de cada grupo foram sacrificados em 7 momentos experimentais: 7, 15, 30, 60, 90, 120 e 180 dias após a evisceração. Após o sacrifício, o conteúdo da cavidade orbitária direita foi removido e seccionado na porção central em duas hemi-metades,uma das quais foi preparada para exame histopatológico; exame ultra-estrutural em microscópio eletrônico de varredura foi feito em dois animais de 7, 60 e 180 dias, de ambos os grupos experimentais. Resumo 118 Resultados: Observou-se aos 7 dias, tecido conjuntivo frouxo, constituído de células inflamatórias e hemáceas, em meio à rede de fibrina, principalmente na periferia da esfera de hidroxiapatita e chegando até ao centro da esfera de polietileno; a reação tecidual tornou-se mais densa com o passar do tempo. Decorridos 60 dias, observou-se em G1, início de metaplasia óssea que se acentuou ao longo do experimento. Em todos os momentos experimentais, a inflamação,predominantemente macrofágica, foi muito mais acentuada em G1.O volume da cavidade esclero-corneana foi melhor mantido em G2. Conclusão: a esfera de hidroxiapatita sintética provoca mais inflamação que a de polietileno poroso e é menos eficiente na manutenção do volume orbitário... (Resumo completo, clicar acesso eletrônico abaixo)

Alterações epigenéticas e do número de cópias do gene SFN em carcinomas mamários

Pós-graduação em Ciências Biológicas (Genética) - IBB