Acquisition of Serum Antibodies Reactive With Enterohemorrhagic Escherichia coli Virulence-Associated Factors by Healthy Brazilian Children and Adults

Background: Patients with hemorrhagic colitis or hemolytic uremic syndrome due to enterohemorrhagic Escherichia coli (EHEC) develop serum IgM and IgG response to lipopolysaccharide (LPS) and to virulence factors such as intimin. The small numbers of cases of diarrhea associated with EHEC strains in Brazil suggests a pre-existing immunity probably due to previous contact with diarrheagenic E. coli. Our aim was to evaluate the development of the serum antibody repertoire to EHEC virulence factors in Brazilian children and adults. Methods: Serum IgM and IgG antibodies were determined by enzyme-linked immunosorbent assay with LPS O111, LPS O26, and LPS O157 in 101 children between 2 months and 10 years of age and in 100 adult sera, by immunoblotting with protein membrane extracts and purified beta intimin; the ability of adult sera to neutralize Shiga toxin2 was also investigated. Results: Children older than 24 months had IgM concentrations reactive with the 3 LPS equivalent to those seen in the adult group, and significantly higher than the group of younger children (P < 0.05). Anti-O26 and anti-O157 LPS IgG concentrations were equivalent between the 2 groups of children and were significantly different from the adult group (P < 0.05). The anti-O111 LPS IgG levels in older children were intermediate between the younger group, and adults (P < 0.05). Immunoblotting revealed strong protein reactivity, including the conserved and variable regions of beta intimin and more than 50% of the adult samples neutralized Shiga toxin 2. Conclusions: Our results demonstrate an increasing anti-LPS and antiprotein antibody response with age, which could provide protection against EHEC infections.

Atypical enteropathogenic Escherichia coli genomic background allows the acquisition of non-EPEC virulence factors

Atypical enteropathogenic Escherichia coli (aEPEC) has been associated with infantile diarrhea in many countries. The clonal structure of aEPEC is the object of active investigation but few works have dealt with its genetic relationship with other diarrheagenic E. coli (DEC). This study aimed to evaluate the genetic relationship of aEPEC with other DEC pathotypes. The phylogenetic relationships of DEC strains were evaluated by multilocus sequence typing. Genetic diversity was assessed by pulsed-field gel electrophoresis (PFGE). The phylogram showed that aEPEC strains were distributed in four major phylogenetic groups (A, B1, B2 and D). Cluster I ( group B1) contains the majority of the strains and other pathotypes [enteroaggregative, enterotoxigenic and enterohemorrhagic E. coli ( EHEC)]; cluster II ( group A) also contains enteroaggregative and diffusely adherent E. coli; cluster III ( group B2) has atypical and typical EPEC possessing H6 or H34 antigen; and cluster IV ( group D) contains aEPEC O55:H7 strains and EHEC O157:H7 strains. PFGE analysis confirmed that these strains encompass a great genetic diversity. These results indicate that aEPEC clonal groups have a particular genomic background - especially the strains of phylogenetic group B1 that probably made possible the acquisition and expression of virulence factors derived from non-EPEC pathotypes.

Effectiveness of Oral Rinse with Chlorhexidine in Preventing Nosocomial Respiratory Tract Infections among Intensive Care Unit Patients

OBJECTIVE. To evaluate the effectiveness of the oral application of a 0.12% solution of chlorhexidine for prevention of respiratory tract infections among intensive care unit (ICU) patients. DESIGN. The study design was a double-blind, randomized, placebo-controlled trial. SETTING. The study was performed in an ICU in a tertiary care hospital at a public university. PATIENTS. Study participants comprised 194 patients admitted to the ICU with a prospective length of stay greater than 48 hours, randomized into 2 groups: those who received chlorhexidine (n = 98) and those who received a placebo (n = 96). INTERVENTION. Oral rinses with chlorhexidine or a placebo were performed 3 times a day throughout the duration of the patient`s stay in the ICU. Clinical data were collected prospectively. RESULTS. Both groups displayed similar baseline clinical features. The overall incidence of respiratory tract infections (RR, 1.0 [95% confidence interval [CI], 0.63-1.60]) and the rates of ventilator-associated pneumonia per 1,000 ventilator-days were similar in both experimental and control groups (22.6 vs 22.3; P = .95). Respiratory tract infection-free survival time (7.8 vs 6.9 days; P = .61), duration of mechanical ventilation (11.1 vs 11.0 days; P = .61), and length of stay (9.7 vs 10.4 days; P = .67) did not differ between the chlorhexidine and placebo groups. However, patients in the chlorhexidine group exhibited a larger interval between ICU admission and onset of the first respiratory tract infection (11.3 vs 7.6 days; P = .05). The chances of surviving the ICU stay were similar (RR, 1.08 [95% CI, 0.72-1.63]). CONCLUSION. Oral application of a 0.12% solution of chlorhexidine does not prevent respiratory tract infections among ICU patients, although it may retard their onset.

Evaluation of Oral Antiseptic Rinsing before Sputum Collection To Reduce Contamination of Mycobacterial Cultures

To assess whether rinsing with oral antiseptics before sputum collection would reduce contamination of mycobacterial cultures, 120 patients with suspected tuberculosis were randomly assigned to rinse with chlorhexidine or cetylpyridinium mouthwash before collection. The culture contamination rate was significantly lower after rinsing with chlorhexidine before collection, especially for cultures grown in MGIT medium.

Effect of Oral Hygiene with 0.12% Chlorhexidine Gluconate on the Incidence of Nosocomial Pneumonia in Children Undergoing Cardiac Surgery

OBJECTIVE. To evaluate the effect of oral hygiene with 0.12% chlorhexidine gluconate on the incidence of nosocomial pneumonia and ventilator-associated pneumonia (VAP) in children undergoing cardiac surgery. DESIGN. Prospective, randomized, double-blind, placebo-controlled trial. SETTING. Pediatric intensive care unit (PICU) at a tertiary care hospital. patients. One hundred sixty children undergoing surgery for congenital heart disease, randomized into 2 groups: chlorhexidine (n = 87) and control (n = 73). INTERVENTIONS. Oral hygiene with 0.12% chlorhexidine gluconate or placebo preoperatively and twice a day postoperatively until PICU discharge or death. RESULTS. Patients in experimental and control groups had similar ages (median, 12.2 vs 10.8 months; P =. 72) and risk adjustment for congenital heart surgery 1 score distribution (66% in category 1 or 2 in both groups; P =. 17). The incidence of nosocomial pneumonia was 29.8% versus 24.6% (Pp. 46) and the incidence of VAP was 18.3% versus 15% (Pp. 57) in the chlorhexidine and the control group, respectively. There was no difference in intubation time (P =. 34), need for reintubation (P =. 37), time interval between hospitalization and nosocomial pneumonia diagnosis (P =. 63), time interval between surgery and nosocomial pneumonia diagnosis (P =. 10), and time on antibiotics (P =. 77) and vasoactive drugs (P =. 16) between groups. Median length of PICU stay (3 vs 4 days; P =. 53), median length of hospital stay (12 vs 11 days; P =. 67), and 28-day mortality (5.7% vs 6.8%; P =. 77) were also similar in the chlorhexidine and the control group. CONCLUSIONS. Oral hygiene with 0.12% chlorhexidine gluconate did not reduce the incidence of nosocomial pneumonia and VAP in children undergoing cardiac surgery.

Prognostic factors and survival analysis in a sample of oral squamous cell carcinoma patients

Objectives. The aims of this report were to describe the 5-year overall survival (OS) in a group of oral squamous cell carcinoma (OSCC) patients and to investigate the effects of age, gender, anatomic localization, tumor evolution time, smoking and alcohol intake, nodal status, tumoral recurrences, histologic classification, p53 and p63 immunoexpression, human papillomavirus DNA presence, and treatment on the prognostic outcome. Study design. Survival curves were generated using Kaplan-Meier method, and univariate and multivariate analyses were made using the log rank test and Cox regression, respectively. Results. The 5-year OS was 28.6%, and the univariate analysis showed significant results for p53 and p63 immunoexpression, age, and anatomic localization. The Cox regression demonstrated poor OS for tumors with p53 immunoexpression and for patients aged over 60 years. There were also significant differences in survival depending on the anatomic localizations. Conclusion. These results highlight the influence of p53 immunoexpression, age, and anatomic localization in OSCC evolution. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2008; 106: 685-95)

Is pain relief equally efficacious and free of side effects with repeated doses of oral sucrose in preterm neonates?

The aim of the present study was to examine the efficacy and potential side effects of repeated doses of oral sucrose for pain relief during procedures in NICU. Thirty-three preterm neonates were randomly allocated in blind fashion into two groups, the sucrose group (SG = 17) and the control group (CG = 16). The responses of neonates to pain and distress were assessed during blood collection on four consecutive assessment (ass.) days. For the first assessment, the neonates did not receive any solution before the blood collection procedure. During the next three days, the SG received oral sucrose (25%; 0.5 ml/kg) and the CG received sterile water, 2 min before each minor acute painful procedure. The neonates were evaluated during blood collection each morning. The assessment was divided into five phases: Baseline (BL), Antisepsis (A), Puncture (P), Dressing (D), and Recovery (R). The neonates` facial activity (NFCS), behavioral state, and heart rate were evaluated. The data analysis used cut-off scores for painful and distressful responses. No side effects of using sucrose were detected. There were significantly fewer SG neonates with facial actions signaling pain than CG neonates in P (ass.2) and in A (ass.3). We found significantly fewer SG neonates in the awake state than CG neonates in P (ass.2 and ass.4). There were significantly fewer SG neonates crying during A (ass.2), P (ass.2 and ass.4), and D (ass.3). There was no statistical difference between-groups for physiological response. The efficacy of sucrose was maintained for pain relief in preterm neonates with no side effects. (C) 2007 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

Neuroprotective effects of oral lamotrigine administration on rabbit retinas after pars plana vitrectomy and silicone oil injection

Purpose: To investigate potential retinal neuroprotective effects of oral lamotrigine in rabbits after pars plana vitrectomy (PPV) and intravitreal silicone oil injection (SOI). Methods: Twelve New Zealand rabbits (weight, 2.0-2.5 kg) underwent PPV with SOI on the right eye. For 30 days postoperatively, 6 rabbits received a daily oral dose of lamotrigine (25 mg/kg), and 6 rabbits received a daily oral dose of water. The animals were killed 30 days after surgery. All retinas were processed histologically, immunostained using glial fibrillary acidic protein (GFAP), and analyzed by fluorescence microscopy. Retina sections from all groups were analyzed by TUNEL for the presence of apoptosis and stained with hematoxylin-eosin for morphologic analysis and retina cell density measurements in each layer using a Zeiss Axiophot microscope and KS 400 software. Results: Retinas from water-operated eyes showed a significant decrease in cell density associated with cell death compared with retinas from water-control eyes; cell density was reduced by 56% in the outer nuclear layer (ONL), 49% in the inner nuclear layer (INL), and 64% in the ganglion cell layer (GCL). Lamotrigine-operated retinas showed a reduction in cell death when compared with water-operated retinas; cell death was reduced by 52% in the ONL, 25% in the INL, and 56% in the GCL. Water-operated retinas showed TUNEL-positive cells and GFAP immunofluorescence throughout Muller cell processes; lamotrigine-operated retinas showed no TUNEL-positive cells and decreased GFAP staining when compared with water-operated retinas. Conclusions: PPV with SOI was associated with apoptosis of retinal cells and activation of glial cells in rabbit eyes. Oral lamotrigine administration provided protection against these effects.

Use of laser phototherapy on a delayed wound healing of oral mucosa previously submitted to radiotherapy: case report

Radiotherapy produces both acute and delayed effects on mucosal tissues, disturbing their healing. This report shows a successful treatment with laser phototherapy (LPT) on a delayed wound healing in oral mucosa previously submitted to radiotherapy with a follow up of 3 years. A 47-year-old patient treated 6 months earlier for tongue squamous cell carcinoma by surgery and radiotherapy presented with a mass in the operated area. Biopsy showed chronic inflammatory infiltrate around a residual polyglactin suture. After 2 months there was a painful mucosal dehiscence on the biopsy site. LPT was performed using a semiconductor laser with 660-nm wavelength (InGaAlP) and spot size of 0.04 cm(2). The parameters applied were 40 mW, 4 Jcm(2)/point, 0.16 J/point, 2.4 J/session. The irradiation was performed punctually, through contact mode in 15 points (4 seconds/point), on top of and around the lesion, during ten sessions. The wound healed completely after ten sessions. This treatment proved to be conservative and effective, inducing healing of a chronic wound in a tissue previously submitted to radiotherapy.

The immunohistochemical profile of oral inflammatory myofibroblastic tumors

Objective. The aim of this study was to demonstrate the immunohistochemical profile of oral inflammatory myofibroblastic tumors (IMTs) along with morphologic analysis. Study design. Three cases diagnosed as oral IMTs were selected to compile an immunohistochemical panel constituted by calponin, caldesmon, Bcl-2, desmin, fibronectin, CD68, Ki-67, S100, anaplastic lymphoma kinase (ALK), alpha-smooth muscle actin, cytokeratins AE1/AE3, muscle-specific actin, CD34, and vimentin. An oral squamous cell carcinoma with a focal area of desmoplastic stroma was used as control for the stained myofibroblastic cells. Results. All oral IMTs were positive for calponin, revealing a strong and diffuse expression in the spindle-shaped cells. The lesions were also positive for vimentin (3/3), fibronectin (3/3), alpha-smooth muscle actin (3/3), and muscle-specific actin (1/3) and negative for h-caldesmon, Bcl-2, desmin, CD68, Ki-67, S100, ALK, cytokeratins AE1/AE3, and CD34. Conclusions. Within the results encountered, the present panel should be of great assistance in the diagnosis of oral IMTs. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2011; 111: 749-756)

Kaposi sarcoma and paracoccidioidomycosis in the same fragment of oral mucosa biopsy: a rare association in human immunodeficiency virus-positive patient. A case report

The immunossuppression caused by HIV infection makes the affected individuals more susceptible to some diseases including infections, neoplasms, or even the association between them. Kaposi sarcoma (KS) is the most common AIDS-related neoplasm, featured as an angioproliferative disorder. Its cause seems to be related to the human herpesvirus type 8 and it is usually associated with lower CD4+ T cell count. Oral involvement is frequent, presenting red to blue-purplish plaques, maculaes, and nodules. On the other hand, paracoccidioidomycosis (PCM) is a systemic mycosis, endemic in Latin America, caused by Paracoccidioides brasiliensis. This mycosis is not commonly related to human immunodeficiency virus (HIV) infection, although PCM can be present in immunosuppression cases. Oral lesions, as granulomatous ulcers, are often identified in seropositive patients with PCM. A rare case, in which a male HIV-positive patient presented simultaneously Kaposi sarcoma and PCM in the same fragment of oral mucosa biopsy, is described. To the best of our knowledge, this concomitant association had not been previously described. (C) 2011 Elsevier Inc. All rights reserved.

Diagnostic implications of oral intravascular papillary endothelial hyperplasia

This study examined the clinical, histological, and immunohistochemical features as well as the differential diagnoses of oral intravascular papillary endothelial hyperplasia (IPEH) to aid clinicians and pathologists in its diagnosis. Clinical features of five oral IPEH cases were obtained from medical records, and all histopathological diagnoses were reviewed. Immunohistochemical reactions, including anti-CD-34, laminin, vimentin, estrogen receptor alpha, and Ki-67, were assessed. Microscopically, a reactive proliferation of vascular cells composed of small papillary structures with hypocellular and hyalinized cores arising in an organized thrombus was seen. CD-34, vimentin, and laminin staining were strongly positive, while estrogen receptor alpha was negative in all cases. A low percentage of cells were positive for Ki-67 in four of five lesions, but one case was strongly positive. A diagnosis of angiosarcoma was investigated and rejected. IPEH presents specific microscopic characteristics that along with clinical data lead to an accurate diagnosis. The general dentist, the first to participate in the diagnostic process, must share the responsibility for diagnosis with the pathologist, and they must work together to determine the correct diagnosis and management. Oral lesions of IPEH are uncommon. Their main significance is that they show a microscopic resemblance to angiosarcoma. Thus, clinicians should have more information regarding this benign entity. Finally, we suggest that in recurrent cases exhibiting strong immunolabeling of proliferative markers the possibility of angiosarcoma should be investigated.