Development of a Model of Natural Infection with Mycobacterium bovis in White-Tailed Deer

The objective of this study was to develop a suitable experimental model of natural Mycobacterium bovis infection in white-tailed deer (Odocoileus virginianus), describe the distribution and character of tuberculous lesions, and to examine possible routes of disease transmission. In October 1997, 10 mature female white-tailed deer were inoculated by intratonsilar instillation of 2 3 103 (low dose) or 2 3 105 (high dose) colony forming units (CFU) of M. bovis. In January 1998, deer were euthanatized, examined, and tissues were collected 84 to 87 days post inoculation. Possible routes of disease transmission were evaluated by culture of nasal, oral, tonsilar, and rectal swabs at various times during the study. Gross and microscopic lesions consistent with tuberculosis were most commonly seen in medial retropharyngeal lymph nodes and lung in both dosage groups. Other tissues containing tuberculous lesions included tonsil, trachea, liver, and kidney as well as lateral retropharyngeal, mandibular, parotid, tracheobronchial, mediastinal, hepatic, mesenteric, superficial cervical, and iliac lymph nodes. Mycobacterium bovis was isolated from tonsilar swabs from 8 of 9 deer from both dosage groups at least once 14 to 87 days after inoculation. Mycobacterium bovis was isolated from oral swabs 63 and 80 days after inoculation from one of three deer in the low dose group and none of four deer in the high dose group. Similarly, M. bovis was isolated from nasal swabs 80 and 85 days after inoculation in one of three deer from the low dose group and 63 and 80 days after inoculation from two of four deer in the high dose group. Intratonsilar inoculation with M. bovis results in lesions similar to those seen in naturally infected white-tailed deer; therefore, it represents a suitable model of natural infection. These results also indicate that M. bovis persists in tonsilar crypts for prolonged periods and can be shed in saliva and nasal secretions. These infected fluids represent a likely route of disease transmission to other animals or humans.

Milk Containing Mycobacterium bovis as a Source of Infection for White-Tailed Deer Fawns (Odocoileus virginianus)

Setting:White-tailed deer represent the first wildlife reservoir of Mycobacterium bovis in the United States. The behavior of does with nursing fawns provides several potential mechanisms for disease transmission. Little information exists concerning transmission between doe and fawn, specifically transmammary transmission. Objective: Determine if fawns can become infected by ingestion of milk replacer containing M. bovis, thus simulating transmission from doe to fawn through contaminated milk. Design: Seventeen, 21-day-old white-tailed deer fawns were inoculated orally with 2x108 CFU (high dose, n=5), 2.5 x 105 to 2.5 x 106 CFU (medium dose, n=5), and 1x104 CFU (low dose, n=5) of M. bovis in milk replacer. Dosages were divided equally and fed daily over a 5-day period. Positive control fawns (n=2) received 1x105 CFU of M. bovis instilled in the tonsillar crypts. Fawns were euthanized and examined 35-115 days after inoculation and various tissues collected for bacteriologic and microscopic analysis. Results: All fawns in the tonsillar, high oral and medium oral dose groups developed generalized tuberculosis involving numerous organs and tissues by 35-84 days after inoculation. Three of five fawns in the low-dose oral group had tuberculous lesions in the mandibular lymph node, and one of five had lesions in the medial retropharyngeal lymph node when examined 115 days after inoculation. Conclusion: White-tailed deer fawns can become infected through oral exposure to M. bovis. Therefore, the potential exists for fawns to acquire M. bovis while nursing tuberculous does.

Susceptibility of Raccoons (Procyon lotor) to Infection with Mycobacterium bovis

Tuberculosis due to Mycobacterium bovis infection is endemic in white-tailed deer (Odocoileus virginianus) in the northeastern portion of the lower Michigan peninsula (USA). Various wild carnivores and omnivores, including raccoons (Procyon lotor), are infected with M. bovis within the endemic area. To investigate the pathogenesis of tuberculosis in raccoons and the likelihood of M. bovis transmission from infected raccoons to other susceptible hosts, we experimentally inoculated raccoons with single oral doses of M. bovis (ranging from 30 to 1.7 x 105 colony forming units [CFU]), five daily oral doses of M. bovis (ranging from 10 to 1 x 105 CFU), or a single intravenous (IV) dose of 1 x 105 CFU of M. bovis, from November 1998 through December 2000. Granulomatous lesions consistent with tuberculosis, or tissue colonization with M. bovis, were seen in one of five raccoons in the single low oral dose group, one of five raccoons in the multiple low oral dose group, two of five raccoons in the multiple medium oral dose group, five of five raccoons in the multiple high oral dose group, and five of five raccoons in the IV inoculated group. In orally inoculated raccoons, lesions were most common in the tracheobronchial and mesenteric lymph nodes and lung. Excretion of M. bovis in saliva or nasal secretions was noted in all IV inoculated raccoons and two of five multiple low oral dose raccoons. Mycobacterium bovis was not isolated from urine or feces from any experimentally inoculated raccoons. The need for multiple large oral doses to establish infection, and the low number of orally inoculated raccoons that excreted M. bovis in nasal secretions or saliva, suggest that widespread tuberculosis among raccoons is unlikely.

Efficacy of Oral and Parenteral Routes of Mycobacterium bovis Bacille Calmette-Guerin Vaccination Against Experimental Bovine Tuberculosis in White-Tailed Deer (Odocoileus virginianus): A Feasibility Study

We investigated the efficacy of oral and parenteral Mycobacterium bovis bacille Calmette-Guerin Danish strain 1331 (BCG) in its ability to protect white-tailed deer (Odocoileus virginianus) against disease caused by M. bovis infection. Twenty-two white-tailed deer were divided into four groups. One group (n=5) received 109 colony-forming units (cfu) BCG via a lipid-formulated oral bait; one group (n=5) received 109 cfu BCG in culture directly to the oropharynx, one group (n=6) was vaccinated with 106 cfu BCG subcutaneously, and one group served as a control and received culture media directly to the oropharynx (n=6). All animals were challenged 3 mo after vaccination. Five months postchallenge the animals were examined for lesions. Results indicate that both oral forms of BCG and parenterally administerd BCG offered significant protection against M. bovis challenge as compared to controls. This study suggests that oral BCG vaccination may be a feasible means of controlling bovine tuberculosis in wild white-tailed deer populations.

Nanoencapsulação de compostos de rutênio, análise de sua atividade anti - Mycobacterium tuberculosis e biodisponibilidade oral

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

Expression of nonclassical molecule human leukocyte antigen-G in oral lesions

Introduction: Human leukocyte antigen (HLA)-G is a nonclassic class I molecule that acts as a modulator of immune responses, and the expression of these molecules in virus-infected cells has been associated with subversion of the immune response. Objective: In this study, we performed a cross-sectional study, systematically comparing the expression of the HLA-G in benign, premalignant, and malignant oral lesions and correlating it with the presence of high-risk and low-risk human papillomavirus (HPV) types. Specimens and Methods: Oral biopsies were collected from 51 patients and analyzed by immunohistochemistry using anti HLA-G antibody. Human papillomavirus detection and typing from oral biopsies were obtained by polymerase chain reaction using GP5+/GP6+ and specific primers. Results: The 51 biopsies were stratified into 3 groups according to lesion grade: oral benign lesions (oral hyperplasia and papilloma, n = 16), oral premalignant lesions (oral leukoplakia with dysplasia and lichen planus, n = 17), and malignant lesions (oral squamous cell carcinoma, n = 18). Human leukocyte antigen G overexpression was mainly observed in benign and premalignant oral lesions but was not related to HPV infection (P>.05). On the other hand, HPV DNA was detected in 24 (47%) oral lesions, mainly in benign and premalignant lesions, with the most frequent type detected being high-risk HPV type. Conclusion: The HLA-G molecule was expressed in a significant number of benign oral lesions and was not correlated with HPV infection or oral cancer. Crown Copyright (C) 2012 Published by Elsevier Inc. All rights reserved.

Oral Lesions in Renal Transplant

To prevent rejection of kidney transplants, patients must be kept in immunosuppressive therapy for a long time, which includes the use of drugs such as cyclosporine, azathioprine, cyclophosphamide, and prednisone. The action of these drugs reduces the general immune response of transplant patients and thus increases their susceptibility to infections. Moreover, these drugs increase the potential of developing lesions. Therefore, oral hygiene in kidney transplant recipients contributes to maintenance of the transplanted organ and its function. Thus, an investigation of oral lesions could be counted as a notable work. The aim of this study was to investigate oral lesions in a group of 21 kidney transplant patients under immunosuppressive therapy attended during a 1-year period in the Nephrology Department of the Federal University of Sergipe, Brazil. Data related to sex, age, etiology of renal disease, types of renal transplant, time elapsed after transplantation, immunosuppressive treatment, use of concomitant agents, and presence of oral lesions were obtained. All patients received a kidney transplant from a living donor, and the mean posttransplantation follow-up time was 31.6 months; 71.5% used triple immunosuppressive therapy with cyclosporine A, azathioprine, and prednisone. Ten patients were also treated with calcium-channel blockers. Of the 21 transplant patients, 17 (81%) presented oral lesions. Gingival overgrowth was the most common alteration, followed by candidiasis and superficial ulcers. One case of spindle cell carcinoma of the lower lip was observed. Oral cavity can harbor a variety of manifestations related to renal transplantation under immunosuppressive therapy.

Porphyromonas gingivalis infection at different gestation periods on fetus development and cytokines profile

Oral Diseases (2012) 18, 648654 Aim: Infective agents may affect pregnancy outcomes by deregulating homeostasis. Objectives: The effects of Porphyromonas gingivalis infection before and at different gestation periods were evaluated. Materials and Methods: Wistar rats infected via subcutaneous with P. gingivalis W83, one week before mating (BM), days 1 (PR1) and 11 of gestation (PR11), and controls were evaluated, and samples were obtained at the end of gestation. P. gingivalis was detected by PCR. Cytokine was determined by ELISA. Results: Infected rats had lower maternal gain of weight. Implantation was not observed in 2/12 BM rats. PR11 presented more fetal-placental resorptions and lower placenta/fetus weight than controls. P. gingivalis was detected in placenta and fetus. IL-6 and TNF-a levels were higher in placenta and serum of infected groups, except for TNF-a in placenta of PR1. IL-1 beta levels were higher in placenta of PR11, but lower in serum and placenta of PR1. There were no differences in IL-10 and PGE2 concentrations among the groups (P < 0.05). Conclusions: The experimental infection by P. gingivalis resulted in alterations in the gestational pattern and in fetal development. The consequences of infection at mid-gestation were more severe than at the beginning, possibly due to the induction of pro-inflammatory cytokines in the fetal compartment.

Oral immunization with attenuated Salmonella vaccine expressing Escherichia coli O157:H7 intimin gamma triggers both systemic and mucosal humoral immunity in mice

Human infections with EHEC such as O157:H7 have been a great concern for worldwide food-industry surveillance. This pathogen is commonly associated with bloody diarrhea that can evolve to the life-threatening hemolytic uremic syndrome. Animals are the natural reservoir where this pathogen remains asymptomatically, in steps of ingestion and colonization of the bowel. The bacterium is shed in the feces, contaminating the surroundings, including water and food that are directed for human consumption. A major player in this colonization process is intimin, an outer membrane adhesion molecule encoded by the E. coli attachment and effacement (eae) gene that has been shown to be essential for intimate bacterial attachment to eukaryotic host cells. In an attempt to reduce the colonization of animal reservoirs with EHEC O157:H7, we designed a vaccine model to induce an immune response against intimin gamma. The model is based on its recombinant expression in attenuated Salmonella, used as a suitable vaccine vector because of its recognized ability to deliver recombinant antigens and to elicit all forms of immunity: mucosal, systemic, and humoral responses. To test this model, mice were orally immunized with a S. enterica serovar Typhimurium strain carrying the pYA3137eaeA vector, and challenged with E. coli O157:H7. Here we show that immunization induced the production of high levels of specific IgG and IgA antibodies and promoted reduction in the fecal shedding of EHEC after challenge. The live recombinant vaccine reported herein may contribute to the efforts of reducing animal intestinal mucosa colonization.

Oral myiasis in an elderly patient

Background: Myiasis is the invasion of living tissue of humans and other mammals by eggs or maggots of flies of the order of Diptera. It occurs mainly in the Tropics and is associated with inadequate public and personal hygiene. Oral myiases in an older man appears to be rare. Objective: To relate a case of oral myiases in a debilitated older man treated by mechanical removal of the maggots, identifying the adult insect that caused the infestation. Methods: The diagnosis of oral myiasis was established by the clinical examination and it was detected that the infestation involved only soft tissue and the sinus cavity. The patient was submitted to two mechanical removal of the visible maggots. Results: Total of 110 maggots was removed from the oral cavity of the patient and adult insects was identified as belonging to the Calliphoridae Family, Cochliomyia hominivorax species. The patient died two days after the second procedure by severe systemic complications. Conclusions: The mechanic removal and the identification of the maggots must be adopted as soon as possible to prevent further tissue damage and bacterial infection in cases of oral myiasis. Special attention should be given to the debilitated old patients that are particularly susceptible to oral myiasis infestation.

Epidemiological study of HPV in oral mucosa through PCR

The Human Papillomavirus (HPV) belongs to the Papillomaviridae family and has a capsid and a single DNA strand. Its infection occurs mainly through sexual intercourse, having an important tropism for skin and mucosal cells. Aim: To evaluate the HPV presence in normal oral mucosa of asymptomatic subjects and; in parallel, to correlate social behavioral habits with the virus. Materials and Methods: Contemporary cohort cross-sectional study. The HPV was found by PCR, using general primers MY09/11 in 125 oral mucosa samples submitted to DNA extraction and PCR to search for the beta-globin gene in order to assess the quality of the extracted DNA. In parallel, we carried out a study of behavioral issues associated with the patients. Results: All the samples had a positive diagnosis of the beta-hemoglobin gene. HPV was diagnosed in 23.2% of the samples analyzed. Conclusion: The virus was present in 29 of the 125 patients, without them having any clinical-pathological manifestation associated with the HPV. As to the social behavior of the patients, we concluded that oral sex is statistically correlated to the virus, and besides the HPV has been statistically more present in female patients.

Lower third molar infection with purulent discharge through the external auditory meatus. Case report and review of literature

This manuscript reports an uncommon case of inferior third molar facial abscess with purulent secretion drainage through the left external acoustic meatus. The patient's left external acoustic meatus was filled with a purulent secretion observed on a CT scan. He underwent surgery to drain the facial abscess. Despite facial abscesses being routine occurrences, the literature does not contain many case reports of odontogenic facial abscesses with drainage via the external acoustic meatus. These situations occur in two possible ways: multiple fissures in the anterior wall of the cartilaginous portion of the external acoustic meatus; and congenital defects that are occasionally present in the anterior-superior aspect of the external acoustic meatus, known as the foramen of Huschke, which allow communication between the external acoustic meatus and mandibular fossa. These defects may also predispose the patient to the spread of the infection or tumour from the external auditory canal to the infratemporal fossa and vice versa. No otological sequelae were observed in this case. The authors conclude that the hypothesis of bone malformation cannot be excluded, and affirm that any facial abscess requires appropriate and immediate treatment for adequate resolution, by removing the causal factor and providing systemic support.

Assessment and management of oral health in liver transplant candidates

Liver transplantation has become a standard treatment for end-stage liver disease and the number of recipients has grown rapidly in the last few years. Dental care during pre-transplant workup is important to reduce potential sources of infection in the drug-induced immunosuppression phase of liver transplantation. Objectives: The objectives of this study were to document the prevalence of oral abnormalities in patients on a liver transplant waiting list presenting to an urban dental school clinic, discuss the appropriate dental treatment according their systemic conditions and compare their oral manifestations with those of healthy individuals. Material and Methods: A pilot study was conducted involving 16 end-stage liver disease individuals (study group- SG) attending the Special Care Dentistry Center of the University of So Paulo and 16 control individuals (control group- CG) with no liver diseases, receiving dental care at the Dental School of the University of So Paulo. These individuals were assessed for their dental status (presence of oral disease or abnormalities), coagulation status, and dental treatment indications. Results: The patients from SG exhibited a greater incidence of oral manifestations compared with CG (p=0.0327) and were diagnosed with at least one oral disease or condition that required treatment. Coagulation abnormalities reflecting an increased risk of bleeding were found in 93.75% of the patients. However, no bleeding complications occurred after dental treatment. Conclusions: The patients with chronic liver diseases evaluated in this study exhibited a higher incidence of oral manifestations compared with the control group and had at least one oral disease or abnormality which required dental treatment prior to liver transplantation. Careful oral examination and evaluation of the patient, including laboratory tests, will ensure correct oral preparation and control of oral disease prior to liver transplantation.

Signaling transduction analysis in gingival epithelial cells after infection with Aggregatibacter actinomycetemcomitans

Periodontal diseases result from the interaction of bacterial pathogens with the hosts gingival tissue. Gingival epithelial cells are constantly challenged by microbial cells and respond by altering their transcription profiles, inducing the production of inflammatory mediators. Different transcription profiles are induced by oral bacteria and little is known about how the gingival epithelium responds after interaction with the periodontopathogenic organism Aggregatibacter actinomycetemcomitans. In the present study, we examined the transcription of genes involved in signaling transduction pathways in gingival epithelial cells exposed to viable A.actinomycetemcomitans. Immortalized gingival epithelial cells (OBA-9) were infected with A.actinomycetemcomitans JP2 for 24 h and the transcription profile of genes encoding human signal transduction pathways was determined. Functional analysis of inflammatory mediators positively transcribed was performed by ELISA in culture supernatant and in gingival tissues. Fifteen of 84 genes on the array were over-expressed (P < 0.01) after 24 h of infection with viable A.actinomycetemcomitans. Over-expressed genes included those implicated in tissue remodeling and bone resorption, such as CSF2, genes encoding components of the LDL pathway, nuclear factor-?B-dependent genes and other cytokines. The ELISA data confirmed that granulocytemacrophage colony-stimulating factor/colony-stimulating factor 2, tumor necrosis factor-a and intercellular adhesion molecule-1 were highly expressed by infected gingival cells when compared with control non-infected cells, and presented higher concentrations in tissues from patients with aggressive and chronic periodontitis than in tissues from healthy controls. The induction in epithelial cells of factors such as the pro-inflammatory cytokine CSF2, which is involved in osteoclastogenesis, may help to explain the outcomes of A.actinomycetemcomitans infection.

Oral Transmission of Chagas Disease

Chagas disease is now an active disease in the urban centers of countries of nonendemicity and endemicity because of congenital and blood and/or organ transplantation transmissions and the reactivation of the chronic disease in smaller scale than vectorial transmission, reported as controlled in countries of endemicity. Oral transmission of Chagas disease has emerged in unpredictable situations in the Amazon region and, more rarely, in areas of nonendemicity where the domiciliary triatomine cycle was under control because of exposition of the food to infected triatomine and contaminated secretions of reservoir hosts. Oral transmission of Chagas disease is considered when >1 acute case of febrile disease without other causes is linked to a suspected food and should be confirmed by the presence of the parasite after direct microscopic examination of the blood or other biological fluid sample from the patient.