Immunohistochemical approach to the pathogenesis of clinical cases of bovine Herpesvirus type 5 infections

Meningoencephalitis by Herpesvirus type 5 (BoHV-5) in cattle has some features that are similar to those of herpetic encephalitis in humans and other animal species. Human Herpesvirus 3 (commonly known as Varicella-zoster virus 1), herpes simplex viruses (HSV), and equid Herpesvirus 1 (EHV-1) induce an intense inflammatory, vascular and cellular response. In spite of the many reports describing the histological lesions associated with natural and experimental infections, the immunopathological mechanisms for the development of neurological disorder have not been established. A total of twenty calf brains were selected from the Veterinary School, University of São Paulo State, Araçatuba, Brazil, after confirmation of BoHV-5 infection by virus isolation as well as by a molecular approach. The first part of the study characterized the microscopic lesions associated with the brain areas in the central nervous system (CNS) that tested positive in a viral US9 gene hybridization assay. The frontal cortex (Fc), parietal cortex (Pc), thalamus (T) and mesencephalon (M) were studied. Secondly, distinct pathogenesis mechanisms that take place in acute cases were investigated by an immunohistochemistry assay. This study found the frontal cortex to be the main region where intense oxidative stress phenomena (AOP-1) and synaptic protein expression (SNAP-25) were closely related to inflammatory cuffs, satellitosis and gliosis, which represent the most frequently observed neurological lesions. Moreover, MMP-9 expression was shown to be localized in the leptomeninges, in the parenchyma and around mononuclear infiltrates (p < 0.0001). These data open a new perspective in understanding the role of the AOP-1, MMP-9 and SNAP-25 proteins in mediating BoHV-5 pathogenesis and the strategies of host-virus interaction in order to invade the CNS.

Influence of hypertension on oral infections and endodontic treatment

Hypertension is characterized by peripheral vascular resistancethat leads to blood pressure increase and severalsystemic changes that may negatively influence one s oralhealth. Thus, the aim of this study was to conduct a literaturereview on the influence of hypertension over oral conditionsand endodontic treatment. Hypertension mainly affects theblood vessels, brain and kidneys. A hypertensive conditioncan lead to increased levels of parathyroid hormones, abnormalvitamin D metabolism, reduction in the concentrationof ionized calcium and decreased calcium absorption.Therefore, hypertension can be closely associated with oralproblems such as periodontal diseases, implant loss, difficultyin bone healing, reduced salivary flow and protein concentrationin saliva, increased number of neutrophils and, as a consequence,favoring of inflammatory processes. It has alsobeen suggested that the success rate of endodontic treatmentin hypertensive patients is lower than in normotensiveones. The response of hypertensive patients to root canaltreatment, intracanal medications and sealers should be furtherstudied in order to provide knowledge on the changes,failures and success of endodontic treatment.

Susceptibility of microorganisms isolated from necrotic pulps to calcium hydroxide

Calcium hydroxide has been used as pulp-capping agent and canal dressing due to its antimicrobial and anti-inflammatory properties besides its ability to induce formation of mineralized tissues. The aim of this study was to evaluate the susceptibility to calcium hydroxide of 146 bacterial strains isolated from endodontic infections. MIC was determined by using an agar dilution method, while contact bactericide activity was performed through in broth. All the isolates were sensitive to calcium hydroxide in concentrations that varied from 0.5mg/ml to 128 mg/ml, and the genera Enterococcus, Pseudomonas, Staphylococcus and Actinomyces were the most resistant. Gramnegative anaerobes proved to be the most sensitive isolates. All the isolates were inhibited after 60 minutes of contact with the alkali in concentration of 100mg/ml

Microbiota asociated with infections of the jaws

The microbial infections involving the craniofacial skeleton, particularly maxilla and mandible, have direct relationship with the dental biofilm, with predominance of obligate anaerobes. In some patients, these infections may spread to bone marrow or facial soft tissues, producing severe and life-threatening septic conditions. In such cases, local treatment associated with systemic antimicrobials should be used in order to eradicate the sources of contamination. This paper discuss the possibility of spread of these infections and their clinical implications for dentistry, as well as their etiology and aspects related to microbial virulence and pathogenesis.

Isolation and molecular identification of Fusobacterium nucleatum from Nigerian patients with oro-facial infections.

Fusobacterium nucleatum is one of the most common anaerobic bacteria present in the oral cavity and is often isolated from infections involving other body sites. To characterise F. nucleatum strains from patients attending a teaching hospital in Nigeria in order to provide information on the methods for accurate identification of anaerobes in clinical specimen. Fusobacterium nucleatum specie from 50 patients presenting with oro-facial infections were studied by culture on Fusobacterium selective agar and fastidious anaerobe agar. The isolates were characterised based on colonial morphology, microscopy, lipase production, susceptibility to kanamycin and colistin and resistance to vancomycin. Biochemical tests were performed using a commercial test kit. The identity of the isolates was confirmed based on molecular characterization performed using polymerase chain reaction (PCR) analysis. Forty-eight (96%) F. nucleatum isolates were obtained from the 50 patients by culture and all the isolates were identified by colonial appearance and microscopy based on their unique spindle shape with tapered ends. Only 26 (54.2%) of the 48 isolates were identified by commercial API 20A test kit while PCR confirmed the identity of all the isolates. Anaerobes are involved in human infections and their study is quite cumbersome due to tedious nature and high cost of the techniques involved. Cultural method is reliable in the isolation and identification of F. nucleatum species. PCR is a rapid and simple method that can complement the phenotypic identification of anaerobes and would assist in their full identification.

Família Enterobacteriaceae, Acinetobacter baumannii e Pseudomonados na microbiota bucal de pacientes mantidos em unidades de terapia intensiva

Enteric organisms, pseudomonads and other opportunistic microorganisms in the oral microbiota have been linked to serious infections in patients hospitalized in intensive care units (ICU). The present study evaluated the presence of family Enterobacteriaceae, Pseudomonas aeruginosa, and Acinetobacter baumannii in the mouth of patients in ICU, correlating it with oral and systemic conditions. Data on health, socioeconomic status, medication use, drug addiction, medical and family histories of patients held for more than 72 hours in the ICU with a diagnosis of severe infection or that developed this condition after entry in said unit were obtained. Fifty patients provided clinical samples of supragingival and subgingival biofilms, saliva and oral mucous membranes were collected, as well as respiratory secretions from patients with pneumonia, blood and urine for sepsis. The presence of target microorganisms was carried out by polymerase chain reaction (PCR) and by culture using selective media. The Chi-square and Mann-Whitney tests were used for statistical analysis, and the significance level was 5%. The intraoral clinical conditions of the patients were poor. The family Enterobacteriaceae was the most prevalent, affecting 39.5% of the supragingival biofilm samples of patients attended in ICU and 18.6% of patients in the control group, besides the rods were the only group found in extraoral samples.

Opportunistic microorganisms in patients with head and neck trauma

The use of antimicrobial agents has facilitated the dissemination of multi-resistant microorganisms, compromising dental and medical treatment. The aim of this study was to evaluate the distribution of different opportunistic microbial species in patients who suffered head and neck trauma, under temporary maintenance in nosocomial environment, particularly intensive care units, on the occurrence of such microorganisms in the oral cavity of the patients. It was selected 38 patients subjected to head and neck traumas. After emergency surgical procedures, clinical samples of saliva, sub and supragingival biofilms and mucosal surfaces were collected at two different moments: just after stabilization of the patient and soon after patients’ release from medical units. The presence of opportunistic and superinfecting microorganisms was evaluated by culture on selective and non-selective media, and the presence of the family Enterobacteriaceae, as well as genera Enterococcus, Pseudomonas, and Staphylococcus was assessed by PCR. It was found that the use of antimicrobials, even for short periods of time was sufficient to facilitate colonization by microorganisms of the families Enterobacteriaceae and Pseudomonadaceae, as well as yeasts and enterococci. These results support the concept that medical and dental teams should make a periodically change of antimicrobials used in treatment protocols in hospital for head and neck trauma patients, in order to minimize dissemination of opportunistic or superinfecting microorganisms.

Multirresistência microbiana e opções terapêuticas disponíveis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effect of oral infections on serum creatinine levels in diabetic rats

Aim: The aim of this study was to evaluate the relationship between pulpal and/or periodontal disease and serum creatinine levels in a rat model of diabetes mellitus. Methods: Eighty male rats (Rattus norvegicus albinus, Wistar) were divided into the following 8 groups compris-ing 10 animals each: normal (G1), with pulpal disease (G2), with periodontal disease (G3), with both pulpal and periodontal disease (G4), diabetic (G5), diabetic with pulpal disease (G6), diabetic with periodontal disease (G7), and diabetic with both pulpal and periodontal disease (G8). Diabetes was induced by injecting streptozotocin, pul-pal disease were induced by exposing pulpal tissue to the oral environment, and periodontal disease was induced by periodontal ligature. After 30 days, blood was collected by cardiac puncture and the animals were killed. The maxillae were processed for histopathology. Serum creatinine levels were measured by the enzymatic method. The total assessed values were statistically analyzed by analysis of variance and Tukey’s test (p < 0.05). Results: Serum creatinine levels were significantly higher in diabetic rats than that in all normoglycemic rats (p < 0.05). The presence of pulpal and periodontal disease increased the serum creatinine levels in normoglycemic and diabetic rats, but there was no statistical difference between the groups (p > 0.05). Conclusions: We found that the serum creatinine level was higher in diabetic rats and may be related to the pres-ence of oral infections. Clinical significance: Changes in serum creatinine level may be related to the presence of oral infections and diabetes.

Microbiota bucal e sua relação com infecções oportunistas em pacientes edêntulos mantidos em unidades de terapia intensiva

Pós-graduação em Odontologia - FOA

Infecção do trato urinário adquirida em ambiente hospitalar em idosos

Introduction: Hospital-acquired urinary tract infection (HAUTI) is an important cause of morbidity in the elderly population. Objective: Evaluate the occurrence of HAUTI and risk factors associated with it. Method: This is a prospective study of a sample of 332 elderly people, interned in a university hospital. Criteria for defining infection were established by the Center for Diseases and Prevention Control. Statistical analysis of data used calculation of frequencies, odds ratio and logistic regression. The rate of hospital infection was 23.6%. The prevalent topographies of infection were respiratory infections (27.6%), urinary tract infections (26.4%) and surgical wound infections (23.6%, with 21, 20 and 19 episodes, respectively. The HAUTI incidence density associated with urinary catheterization was 24.2 infections by 1,000 catheter-days. The length of hospital stay of patients without nosocomial infection was 6.9 days and with HAUTI was increased in 10.4 (p<0.05).The rate of mortality of patients with HAUTI was 20%. Pathogens were isolated in 75% of episodes of HAUTI and the prevalent were: Escherichia coli (33%) and Pseudomonas aeruginosa (20%). Risk factors found for HAUTI were urinary catheterization implementation (odds ratio (OR) = 43.1; 95% confidence interval (95 CI%) = 3.9 – 311.1), hospitalization with community infection (OR= 21.9; 95% CI = 4.9 – 97.9); vascular diseases (OR=14; 95% CI = 2 – 98); diabetes mellitus (OR= 5.5; 95% CI = 1.4 – 21) and urinary catheterization by more than three days (OR=3.7; 95% CI = 1 – 13.8). Conclusions: HAUTI presented elevated incidence and it increased the length of hospital stay.

Genital infections of HIV-infected women assisted by a specialized service

The present study aimed at analyzing the persistence/recurrence of genital infections and its associated factors in HIV-infected women. Fifty-eight women treated for chlamydial infection, trichomoniasis, vulvovaginal candidiasis, and/or bacterial vaginosis (BV) and who had specimens collected for cure control up to one year after treatment were studied. Diagnoses were performed by the Gram staining method for cases of BV and candidiasis and by T. vaginalis culture and qualitative PCR for C. trachomatis. Antiretroviral therapy was used by 79.3% of patients, and 62.1% showed an undetectable HIV plasma load. The most frequent infection was BV with persistence/recurrence of 52.4%, which was associated with a longer time period between treatment and cure control (P = 0.0455), postmenopausal period (P = 0.0451), and having a steady partner (P = 0.007). Persistence/recurrence of vulvovaginal candidiasis was observed in 25%, trichomoniasis in 23.1%, and chlamydial infection in 10.5%. The letter was associated with inadequate treatment of the partner (P = 0.073) among patients with low T CD4 lymphocyte counts. The majority of women in the present study showed good HIV-infection control and a vulnerable sexual behavior, which stress the importance of maintaining gynecological followup.

Etiolofia, epidemiologia e prognóstico das pneumonias associadas à ventilação mecânica em um hospital de ensino, com ênfase no estudo molecular e virulência de Staphylococcus aureus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Reo-Like Virus in White Shrimp Penaeus vannamei (Crustacea: Decapoda): Co-occurrence with Baculovirus penaei in Experimental Infections

A virus, tentatively identified as reo-like, occurred concurrently with experimentally-induced Baculovirus penaei (BP) infection in cultured white shrimp larvae Penaeus vannamei. Each shrimp with a reo-like viral infection also had a BP infection, but not all BP-infected shrimp had a reo-like infection. Both viruses occurred in the same tissues and occasionally withln the same cell. The reolike virus developed in epithelial cells of the anterior midgut and in reserve- and fibrillar-cells of the hepatopancreas. The paraspherical and non-enveloped reo-like virions (ca. 50 nm diam.) occurred as unordered aggregates in the cell cytoplasm. Their etiology has not been determined. Reo-like virions may have been introduced along with the BP virus, or, were latent and only manifested due to stress induced by the more pathogenic BP virus.

Echinococcus Infections in Man and Animals in Kenya

1. Hydatid cysts are found in more than 30 per cent of all cattle, sheep and goats in Kenya, but the disease is prevalent in man only in the semi-desert area of Turkana. Up to the time of the present investigation the life-cycle of the parasite in East Africa had not been studied, but it was suggested that wild carnivores, such as hyenas and jackals, might be the main hosts of the adult worms. 2. One hundred and forty-three carnivores, representing 23 species, have been examined. Echinococcus adults were found in 27 out of 43 domestic dogs (Canis familiaris), in three out of four hunting dogs (Lycaon pictus), in one out of nine jackals (Thos mesomelas), and in three out of 19 hyaenas (Crocuta crocuta). 3. A detailed morphological study was made of the Kenya material. After comparison with specimens from other parts of the world, it was concluded that the only species occurring in Kenya was E. granulosus, but it is possible that the minor morphological and biological differences are evidence of distinct strains. Further laboratory studies are necessary to compare the parasite from man and animals in different parts of Kenya with material from elsewhere. 4. A search was made for larval hydatids in 92 ungulates representing 18 species, and in a miscellaneous collection of nearly 2,000 rodents and primates representing a further 31 species. Only one animal was positive, a wildebeest (Gorgon taurinus). 5. The infections in the wild carnivores were all very light; only domestic dogs were heavily infected. It is concluded that the main cycle of transmission in Kenya is between dogs and domestic livestock. 6. Turkana tribesmen are the most heavily infected people in Kenya, either because the strain of parasite is more pathogenic to man in that area, or, more probably, because of the intimate contact between children and the large number of infected dogs. A particularly dangerous custom in the area is the use of dogs to clean the face and anal regions of babies when they vomit or have diarrhea. No satisfactory explanation can be given for the rarity of the disease in man in many of the other areas of Kenya where hydatids are very common in domestic animals. 7. The control of the disease will depend upon an active health-education campaign, together with the destruction of all unregistered dogs and improvement in meat hygiene.