Histological evaluation of the lesion induced by inoculation of Leishmania mexicana in the cheek pouch of the hamster

No presente estudo, investigamos o papel da resposta imune na morfologia do granuloma leishmaniótico induzido na bolsa jugal do hamster, um local imunologicamente privilegiado, após inoculação de 3x10(5) Leishmania mexicana. Os animais foram avaliados histológica e imunologicamente até os 120 dias da inoculação. Independente da época do sacrifício, os animais foram sempre não reatores ao teste do coxim plantar. Histologicamente, a inoculação de Leishmania mexicana na bolsa jugal resultou na formação de abcesso que evoluiu para reação granulomatosa rica em formas amastigotas e, posteriormente, para resolução. Esses resultados sugerem que o desenvolvimento da resposta imune não é preponderante no controle da infecção induzida pela Leishmania mexicana inoculada subcutaneamente na bolsa jugal do hamster. Sugerem ainda que os macrófagos que compõe os granulomas leishmanióticos são capazes de eliminar esse parasita, independente da presença de resposta imune avaliável pelo teste do coxim plantar.

Laryngeal lesion in leprosy and the risk of aspiration

Leprosy affects the larynx, damaging its mucosa and sensory nerves and loss of sensation may result in aspiration of food and secretions. The laryngeal lesion may be insidious. Post-mortem studies showed bronchopneumonia that could have originated from aspiration. In patients with laryngeal symptoms, dysphagia or aspiration pneumonia loss of laryngeal sensation should be looked for.

In vitro and skin lesion cytokine profile in Brazilian patients with borderline tuberculoid and borderline lepromatous leprosy

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Iatrogenic cortical aneurysm post-craniotomy

Taking into account the number of craniotomies performed every day around the world, iatrogenic aneurysm post-craniotomy is extremely rare with only anecdotal cases reported in literature. We report an iatrogenic aneurysm affecting a cortical vessel which probably developed during dural closure of a conventional craniotomy. The aneurysm was discovered 6 months after surgery on a routine control angiography. The patient was successfully treated by trapping the parent vessel and excising the aneurysm. Histopathological findings were compatible with a true type of traumatic aneurysm. The possibility of this rare condition occurring highlights the risk of arterial injury during craniotomy.

Is Reinke's Edema a Precancerous Lesion? Histological and Electron Microscopic Aspects

The objectives of this study were to evaluate morphologic alterations and precancerous lesions in Reinke's edema. Patients included were 54 smokers with bilateral Reinke's edema submitted to surgery in the Otolaryngology Department, Botucatu Medical School, São Paulo State University, Brazil, between 2002 and 2006. All specimens were evaluated by light microscopy and five contralateral lesions were also evaluated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The main histological alterations were edema (100%), inflammation (81.48%), basal membrane (bm) thickening (77.77%), and vessel proliferation (75.92%). Epithelium alterations were classified as grade 0 (11.11%), grade 1 (70.37%), grade 2 (14.81%), and grade 3 (3.70%). In the case included in grade 3 classification, microinvasive carcinoma was detected. SEM showed epithelial surface with some cellular desquamation, few microridges, and a polished and impermeable surface aspect. TEM showed epithelial hyperplasia, basal cells with different sizes, widening of the intercellular spaces, abnormal desmosome architecture, thickening of the bm, some electron-dense vesicles, and points of interruption. The morphological alterations presented in this study are not specific to Reinke's edema but this lesion can be the site of different grades of dysplasia and carcinoma, justifying the importance of periodic laryngeal endoscopic exams and meticulous histological analysis.

Necrotic skin lesion in a dog attributed to Loxosceles (brown spider) bite: a case report

Envenomations caused by Loxosceles (brown spider) have been reported throughout the world. Clinical signs associated to bites of these spiders involve dermonecrotic lesions and intense local inflammatory response, besides systemic manifestations such as intravascular hemolysis, thrombocytopenia, disseminated intravascular coagulation and acute renal failure. The present study aimed to report and to describe dermonecrotic lesions probably caused by a Loxosceles envenomation in a four year-old poodle female dog, treated at the Dermatology Service of the Veterinary Hospital of the Veterinary Medicine and Animal Husbandry School, São Paulo State University, Botucatu, Brazil. Initially, the animal presented two skin lesions with blackish aspect that evolved into ulcerative crusts. The owner reported the presence of a brown spider near the place where the animal spent most of the time. Histological examination of lesions revealed necrosis of the epidermis extending to adnexa and panniculi, which is compatible with Loxosceles bite reaction. The animal was treated with systemic antibiotic and local curatives. Lesions healed by second intention in two months.

Porencephaly and cortical dysplasia as cause of seizures in a dog

Background: Seizures are a common problem in small animal neurology and it may be related to underlying diseases. Porencephaly is an extremely rare disorder, and in Veterinary Medicine it affects more often ruminants, with only few reports in dogs.Case presentation: A one-year-old intact male Shih-Tzu dog was referred to Veterinary University Hospital with history of abnormal gait and generalized tonic-clonic seizures. Signs included hypermetria, abnormal nystagmus and increased myotatic reflexes. At necropsy, during the brain analysis, a cleft was observed in the left parietal and occipital lobes, creating a communication between the subarachnoid space and the left lateral ventricle, consistent with porencephaly; and also a focal atrophy of the caudal paravermal and vermal portions of the cerebellum. Furthermore, the histological examination showed cortical and cerebellar neuronal dysplasia.Conclusions: Reports of seizures due to porencephaly are rare in dogs. In this case, the dog presented a group of brain abnormalities which per se or in assemblage could result in seizure manifestation.

Cortical Bone Stress Distribution in Mandibles with Different Configurations Restored with Prefabricated Bar-Prosthesis Protocol: A Three-Dimensional Finite-Element Analysis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Detection of periapical lesion development by conventional radiography or computed tomography

Objective. The aim of this study was to detect the development of experimentally induced periapical lesions using conventional radiography and computed tomography.Study design. The root canals of dogs' teeth were exposed to the oral environment for 7 days for contamination and then sealed for 7 days (GI), 15 days (GII), 30 days (GIII), and 60 days (GIV). Immediately after each experimental period, radiographs and tomograms were taken in order to detect the occurrence of periapical bone resorption. The periapical radiographs were digitized and areas of bone resorption were measured using the VIXWIN 2000 software. Scores were assigned to the tomograms based on the progression of periapical bone resorption. The specimens were evaluated by calibrated examiners who were blinded to the groups. The radiographic results were analyzed by ANOVA and Tukey's test (P <.05) and the tomographic results were analyzed by Kruskal-Wallis and Dunn's tests (P <.05).Results. The radiographic evaluation did not reveal periapical lesions at the 7-day control. Lesions were radiographically visible at 15 and 30 days (47.4% and 77.8% of the cases, respectively) and presented similar dimensions (P <.05). At 60 days, lesions were detected in all specimens, presenting larger dimensions than those of the earlier evaluation periods (P <.05). The tomographic evaluation detected lesions at 7 and 15 days (32.5% and 83.3% of the cases, respectively). Lesions were detected in all specimens at the 30- and 60-day periods, when the greatest values of bone resorption were observed (P <.05).Conclusions. Tomography was able to detect periapical lesion development in its initial stages, even when the lesions were undetectable radiographically.

Comparative radiographic and histological analyses of periapical lesion development

Objective. The present study evaluated the dynamics of the development of periapical lesions.Study design. Root canals from dogs' teeth were exposed to the oral environment, and then sealed for 7 days (Group A), 15 days (Group B), 30 days (Group C), and 60 days (Group D). After each experimental period, radiographs were taken to detect periapical bone resorption. In addition, histological sections from the periapical region were prepared. The radiographic and histological results were analyzed by ANOVA and Tukey's, Wilcoxon, and Pearson's tests. Significance level was set at 5%.Results. Lesions were radiographically visible at 15 and 30 days, and had similar size at these periods (P > .05). At 60 days, lesions were larger than in the other periods (P < .05). Bone resorption was detected histologically at 7 days. The greatest values of bone resorption were observed at the 30- and 60-day periods (P < .05). The results of the methods of evaluation were similar only at the 30-day period. There was no correlation between the radiographic and histological results.Conclusions. Periapical radiography did not provide detection of periapical lesion in its initial stages. The periapical lesions became more evident radiographically when the bone resorption area increased. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009;107:442-447)

Effects of AV3V lesion on pilocarpine-induced pressor response and salivary gland vasodilation

The cholinergic agonist pilocarpine injected intraperitoneally (ip) increases mean arterial pressure (MAP) and superior mesenteric (SM) vascular resistance and reduces submandibular/sublingual gland (SSG) vascular resistance. In the present study, we investigated the effects of electrolytic lesions of the anteroventral third ventricle (AV3V) region on the changes in MAP, SM, and SSG vascular resistances induced by ip pilocarpine. Male Holtzman rats anesthetized with urethane (1.0 g/kg) and chloralose (60 mg/kg) were submitted to sham or electrolytic AV3V lesions and bad pulsed Doppler flow probes implanted around the arteries. Contrary to sham rats, in 1-h and 2-day AV3V-lesioned rats, pilocarpine (4 mu mol/kg) ip decreased MAP (-41 +/- 4 and -26 4 mm Hg, respectively, vs. sham: 19 +/- 4 mm Hg) and SM (-48 +/- 11 and -45 +/- 10%, respectively, vs. sham: 41 +/- 10%) and hindlimb vascular resistances (-65 +/- 32 and -113 +/- 29%, respectively, vs. sham: 19 +/- 29%). In 7-day AV3V-lesioned rats, pilocarpine produced no changes on MAP and SM and hindlimb vascular resistances. Similar to sham rats, pilocarpine reduced SSG vascular resistance 1 h after AV3V lesions (-46 +/- 6%, vs. sham: -40 +/- 6%), but it produced no effect 2 days after AV3V lesions and increased SSG vascular resistance (37 6%) in 7-day AV3V-lesioned rats. The responses to ip pilocarpine were similar in 15-day sham and AV3V-lesioned rats. The cholinergic antagonist atropine methyl bromide (10 nmol) iv slightly increased the pressor response to ip pilocarpine in sham rats and abolished for 40 min the fall in MAP induced by ip pilocarpine in 1-h AV3V-lesioned rats. The results suggest that central mechanisms dependent on the AV3V region are involved in the pressor responses to ip pilocarpine. Although it was impaired 2 and 7 days after AV3V lesions, pilocarpine-induced salivary gland vasodilation was not altered 1 h after AV3V lesions which suggests that this vasodilation is not directly dependent on the AV3V region. (c) 2005 Elsevier B.V. All rights reserved.

Effect of electrolytic and chemical lesion by ibotenic acid of the septal area on water and salt intake

Water and sodium chloride intake was studied in male Holtzman rats weighing 250-300 g that had been subjected to electrolytic and chemical lesions of the septal area (SA). Water intake increased in animals with electrolytic lesion of the SA bilaterally from 169.37 +/- 8.55 (sham) to 214.87 +/- 23.10 ml/5 days (lesioned). Water intake decreased after ibotenic acid lesion of the SA from 229.33 +/- 27.60 to 127.33 +/- 22.84 ml/5 days. Sodium chloride intake (1.5%) increased in animals with electrolytic lesion of the SA from 10.0 +/- 1.73 to 15.5 +/- 1.95 ml/5 days after lesion. Also sodium chloride (1.5%) intake increased after ibotenic acid injection into the SA to a greater extent (from 7.83 +/- 1.25 to 14.33 +/- 1.87 ml/5 days). The results indicate that the water intake response may be due to lesions that involve cell bodies and fibers of passage and that the sodium intake response can also be induced by lesions which involve only cell bodies. Finally, these results led us to conclude that the SA uses its cell bodies and afferent bodies and fibers for processing inputs mediating water intake and salt appetite and that the cells bodies of the SA are implicated in increased water intake. (C) 1998 Elsevier B.V.