Activation of Leishmania spp. leishporin: evidence that dissociation of an inhibitor not only improves its lipid-binding efficiency but also endows it with the ability to form pores.

We have previously shown that various species of Leishmania produce a lytic activity, which, in Leishmania amazonensis, is mediated by a pore-forming cytolysin, called leishporin. It is toxic for macrophages in vitro and optimally active at pH 5.0 to 5.

Rickettsia amblyommii infecting Amblyomma auricularium ticks in Pernambuco, northeastern Brazil: isolation, transovarial transmission, and transstadial perpetuation.

This study investigated rickettsial infection in Amblyomma auricularium ticks from the state of Pernambuco, northeastern Brazil. An engorged female of A. auricularium collected from a skunk (Conepatus semistriatus) was sent alive to the laboratory, where the female was found through molecular analysis to be infected by Rickettsia amblyommii.

Getting actionable about community resilience: the Los Angeles County Community Disaster Resilience project.

Community resilience (CR)--ability to withstand and recover from a disaster--is a national policy expectation that challenges health departments to merge disaster preparedness and community health promotion and to build stronger partnerships with organizations outside government, yet guidance is limited. A baseline survey documented community resilience-building barriers and facilitators for health department and community-based organization (CBO) staff. Questions focused on CBO engagement, government-CBO partnerships, and community education.

Genetic diversity of Ehrlichia canis in Brazil.

Canine monocytic ehrlichiosis is a highly prevalent disease in Brazil, where the genetic diversity of Ehrlichia canis remains undefined. In this study, we used the TRP36 gene to examine the genetic diversity of E. canis strains from naturally infected dogs residing in five distinct geographic regions in Brazil.

Initial biochemical and functional characterization of a 5'-nucleotidase from Xylella fastidiosa related to the human cytosolic 5'-nucleotidase I.

The 5'-nucleotidases constitute a ubiquitous family of enzymes that catalyze either the hydrolysis or the transfer of esterified phosphate at the 5' position of nucleoside monophosphates. These enzymes are responsible for the regulation of nucleotide and nucleoside levels in the cell and can interfere with the phosphorylation-dependent activation of nucleoside analogs used in therapies targeting solid tumors and viral infections. In the present study, we report the initial biochemical and functional characterization of a 5'-nucleotidase from Xylella fastidiosa that is related to the human cytosolic 5'-nucleotidase I.

Peer influence and selection processes in adolescent smoking behavior: a comparative study.

Introduction: Adolescent smoking studies find evidence of active peer influence and selection processes. However, studies have shown that these processes operate differently depending on context. This study uses SIENA to model coevolutionary processes between smoking and changes in friendship ties, comparing two high schools in which data were collected in identical fashion to explore influence and selection mechanisms with respect to current smoking, and smoking levels.

Influence of smear layer removal and application mode of MTA on the marginal adaptation in immature teeth: a SEM analysis.

Objectives: This study was an ex vivo evaluation of the marginal adaptation of mineral trioxide aggregate as an apical barrier using teeth with an open apex and scanning electron microscopy.

Materials And Methods: Eighteen single-rooted human teeth were used. An artificial open apex was created using Gates Glidden drills #6-1 in a crown-down manner until the #1 bur passed through the foramen.

Stromal myofibroblasts in focal reactive overgrowths of the gingiva.

Focal reactive overgrowths are among the most common oral mucosal lesions. The gingiva is a significant site affected by these lesions, when triggered by chronic inflammation in response to microorganisms in dental plaque. Myofibroblasts are differentiated fibroblasts that actively participate in diseases characterized by tissue fibrosis.

Cell proliferation and apoptosis in ameloblastomas and keratocystic odontogenic tumors.

A high proliferative activity of the odontogenic epithelium in ameloblastoma (AM) and keratocystic odontogenic tumor (KOT) has been demonstrated. However, no previous study has simultaneously evaluated cell proliferation and apoptotic indexes in AM and KOT, comparing both lesions. The aim of this study was to assess and compare cell proliferation and apoptotic rates between these two tumors.

Reactive oxygen species and nitric oxide in cutaneous leishmaniasis.

Cutaneous leishmaniasis affects millions of people around the world. Several species of Leishmania infect mouse strains, and murine models closely reproduce the cutaneous lesions caused by the parasite in humans. Mouse models have enabled studies on the pathogenesis and effector mechanisms of host resistance to infection.

Cutaneous loxoscelism caused by Loxosceles similis venom and neutralization capacity of its specific antivenom.

Members of the spider genus Loxosceles pose a marked health risk to humans because of the seriousness of the necrotic and systemic effects of their bite, known as loxoscelism. The recent confirmation of Loxosceles similis in residences of Belo Horizonte in Minas Gerais Province, Brazil increases the local potential risk of loxoscelism at higher levels. The first characterization of the venom from this species showed that its main biological effects had a similar intensity as other species (e.

Odontogenic tumours in children and adolescents: a collaborative study of 431 cases.

This study describes the oral and maxillofacial pathological characteristics of a series of odontogenic tumours in children and adolescents from three Brazilian reference centres. The records were reviewed for all odontogenic tumours in patients up to 18 years old based on criteria proposed by the World Health Organization (WHO) in 2005. Data concerning sex, age, skin colour and tumour location were collected and plotted.

Stromal myofibroblasts in oral leukoplakia and oral squamous cell carcinoma.

Objectives: Oral leukoplakia (OL) is the main potentially malignant disorder and oral squamous cell carcinoma (OSCC) is the most common malignancy of the oral mucosa. Stromal myofibroblasts play an important role in tumor invasion and metastasis, due to its ability to modify the extracellular matrix. This study aimed to evaluate the presence of stromal myofibroblasts in OL and OSCC.

Effect of vegetable oil (Brazil nut oil) and mineral oil (liquid petrolatum) on dental biofilm control.

Dental biofilm control represents a basic procedure to prevent caries and the occurrence of periodontal diseases. Currently, toothbrushes and dentifrices are used almost universally, and the employment of good oral hygiene allows for appropriate biofilm removal by both mechanical and chemical control. The aim of this study was to evaluate the effectiveness of adding vegetable or mineral oil to a commercially available dentifrice in dental biofilm control.

Seroprevalence and risk factors to Ehrlichia spp. and Rickettsia spp. in dogs from the Pantanal Region of Mato Grosso State, Brazil.

Sera of 320 dogs from urban and rural areas of a Pantanal region of Brazil were evaluated for rickettsial (Rickettsia rickettsii, R. parkeri, R. amblyommii, R.

Anatomic variations and lesions of the maxillary sinus detected in cone beam computed tomography for dental implants.

Objective: To evaluate the presence of anatomic variations and lesions of the maxillary sinus in cone beam computed tomography (CBCT) of the maxilla required for dental implant planning.

Material And Methods: This transversal prevalence study evaluated a sample of 500 consecutive CBCT exams. The inclusion criteria were CBCT exams of the maxilla required for dental implant planning.

Perception of discomfort during orthodontic treatment with tongue spurs.

Aim: To evaluate patients' and parents' reactions to the orthodontic treatment of open bite patients with a mandibular lingual arch and spurs (MASP) and to compare any changes in anxiety and discomfort during treatment in different age groups and sexes.

Methods: Seventy-two patients completed a baseline questionnaire to assess their levels of discomfort and reaction to this appliance. The patients were divided into two groups: Group 1 consisted of 33 patients up to 14 years of age, and group 2 comprised 39 patients 15 years of age and older.

Isolation and genetic characterisation of Toxoplasma gondii from a red-handed howler monkey (Alouatta belzebul), a jaguarundi (Puma yagouaroundi), and a black-eared opossum (Didelphis aurita) from Brazil.

Toxoplasma gondii isolates are highly diverse in domestic animals from Brazil. However, little is known about the genetics of this parasite from wild mammals in the same region. Reveal genetic similarity or difference of T.

Rickettsia felis infection in cat fleas ctenocephalides felis felis.

The present study evaluated the rickettsial infection in a laboratory colony of cat fleas, Ctenocephalides felis felis (Bouche) in Brazil. All flea samples (30 eggs, 30 larvae, 30 cocoons, 30 males, and 30 females) tested by polymerase chain reaction (PCR) were shown to contain rickettsial DNA. PCR products, corresponding to the rickettsial gltA, htrA, ompA and ompB gene partial sequences were sequenced and showed to correspond to Rickettsia felis, indicating that the flea colony was 100% infected by R.

Experimental infection of the opossum Didelphis aurita by Rickettsia felis, Rickettsia bellii, and Rickettsia parkeri and evaluation of the transmission of the infection to ticks Amblyomma cajennense and Amblyomma dubitatum.

This work evaluated the infection of opossums (Didelphis aurita) by Rickettsia felis, Rickettsia bellii, and Rickettsia parkeri and their role as amplifier hosts for horizontal transmission to Amblyomma cajennense and/or Amblyomma dubitatum ticks. Infection in D. aurita was induced by intraperitoneal inoculation with R.

Periapical repair in dog teeth: root canal adhesive filling by using the Resilon System.

Introduction: New filling biomaterials with better physicochemical properties would create a favorable biologic environment for the healing of periapical tissues. The aim of this study was to evaluate periapical repair after biomechanical preparation and root filling with an adhesive system compared with the gold standard material (gutta-percha+sealer) in dog teeth.

Methods: The pulp of 25 root canals was removed.

Clinical, histological and immunohistochemical features of ectomesenchymal chondromyxoid tumor.

Objective: Ectomesenchymal chondromyxoid tumor is a rare oral soft tissue neoplasm that should be differentiated from other neural and chondromyxoid entities. The aim of this study was to report the clinical, histological, and immunohistochemical features of 3 additional cases of this condition.

Methods: Clinical data were obtained from the clinical records and all cases were evaluated through light microscopy and immunohistochemistry to cytokeratins, vimentin, S100 protein, desmin, smooth muscle actin, and glial fibrilary acidic protein.

Membrane binding requirements for the cytolytic activity of Leishmania amazonensis leishporin.

To lyse cells, some pore-forming proteins need to bind to receptors on their targets. Studying the binding requirements of Leishmania amazonensis leishporin, we have shown that protease-treated erythrocytes are as sensitive to leishporin-mediated lysis as untreated cells, indicating that protein receptors are dispensable. Similarly, carbohydrate receptors do not seem to be needed, since several sugars do not inhibit leishporin-mediated hemolysis.

[Survey of Rickettsia spp in the ticks Amblyomma cajennense and Amblyomma dubitatum in the State of São Paulo].

The presence of rickettsial infection was surveyed in 3,545 Amblyomma cajennense ticks and 2,666 Amblyomma dubitatum ticks. Using the hemolymph test, polymerase chain reaction and isolation of Rickettsia in cell cultures, all of the Amblyomma cajennense were negative, whereas 634 (23.8%) of the Amblyomma dubitatum ticks were shown to be infected with Rickettsia bellii.