Andreia Maria Camargos Rocha

Cytokine Expression Profile Over Time In Severely Burned Pediatric Patients

ABSTRACT A severe burn leads to hypermetabolism and catabolism resulting in compromised function and structure of essential organs. The massive release of cytokines is implicated in this hypermetabolic response. The aim of the present study was to compare cytokine expression profiles from severely burned children without signs of infections or inhalation injury (n = 19) to the cytokine profiles from normal, noninfected, nonburned children (n = 14). The Bio-Plex suspension array system was used to measure the concentration of 17 cytokines. The expression of proinflammatory and anti-inflammatory cytokines was maximal during the first week after thermal injury. Significant increases were measured for 15 mediators during the first week after thermal injury: interleukin (IL) 1&bgr;, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12 p70, IL-13, IL-17, interferon &ggr;, monocyte chemoattractant protein 1, macrophage inflammatory protein 1&bgr;, and granulocyte colony-stimulating factor (P < 0.05). Granulocyte-macrophage colony-stimulating factor was significantly increased during the second week after burn (P < 0.05). Within 5 weeks, the serum concentrations of most cytokines decreased, approaching normal levels. When compared with the cytokine levels measured in normal children, a total of 16 cytokines were significantly altered (P < 0.05). After severe burn, a specific cytokine expression profile is observed in patients without complications such as inhalation injury or sepsis. The cytokine concentrations decrease during 5 weeks after burn but remain elevated over nonburned values. Furthermore, the elevation in most serum cytokine levels during the first week after burn may indicate a potential window of opportunity for therapeutic intervention.

Evaluation of [13C]urea breath test and Helicobacter pylori stool antigen test for diagnosis of H. pylori infection in children from a developing country.

ABSTRACT The [13C]urea breath test (13C-UBT) and Helicobacter pylori stool antigen test (HpSA) for the diagnosis of H. pylori infection in children were validated. The sensitivity, specificity, and positive and negative predictive values were 93.8, 99.1, 97.8, and 98.0%, respectively, for the 13C-UBT and 96.9, 100, 100, and 98.0%, respectively, for HpSA. Both tests are appropriate for diagnosing H. pylori infection in children.

The levels of IL-17A and of the cytokines involved in Th17 cell commitment are increased in patients with chronic immune thrombocytopenia

Th17 cells have been associated with immune-mediated diseases in humans but it has still not been determined whether they play a role in immune thrombocytopenia. We evaluated representative cytokines of the Th17, Th1, Th2 and Treg cell commitment in the serum of patients with chronic immune thrombocytopenia, as well as the cell source of IL-17A. Higher levels of IL-17A and Th17-related cytokines, and an increased percentage of IL-17A producing CD4+ and neutrophils were observed in patients. The levels of cytokines involved in Th1 cell commitment IFN-γ, IL-2, IL12-p70 and the percentages of Th1 cells were also increased, but IL-4 was not detected. Although the concentrations of IL-10 were higher, the levels of TGF-β were similar in both groups. In conclusion, our results point to a putative role for Th-17 cells/IL-17A cytokine in the pathogenesis of chronic immune thrombocytopenia.

Transmission of Helicobacter pylori infection in families of preschool-aged children from Minas Gerais, Brazil.

We evaluated the role of the family in the transmission of Helicobacter pylori infection in preschool‐aged children from a rural district in the State of Minas Gerais, Brazil. Sixty‐six families (66 index children, 63 mothers, 60 fathers and 134 siblings), defined as at least one parent living in the same household with at least one offspring up to 8 years old, were studied. Odds ratios (OR) and 95% confidence intervals (CI) were estimated by logistic regression controlling for age, gender, number of children in household and H. pylori status of the father, mother and siblings. The prevalence of the infection was 69.7% (469 of 673) and it increased with age (P < 0.001). Positive mothers were a strong and independent risk factor for infection (OR 22.70; 95% CI 2.31–223.21). Positive siblings were also positively associated with infection (OR 1.81; 95% CI 1.01–3.30).

babA2- and cagA-positive Helicobacter pylori strains are associated with duodenal ulcer and gastric carcinoma in Brazil.

ABSTRACT The babA2 and cagA genes were investigated in 208 Brazilian Helicobacter pylori strains. A strong association between babA2 and duodenal ulcer or gastric carcinoma was observed, even after adjusting for confounding factors, such as age, gender, and cagA status. cagA-positive strains were also independently associated with H. pylori-related diseases.

IL1RN polymorphic gene and cagA‐positive status independently increase the risk of noncardia gastric carcinoma

Helicobacter pylori cagA‐positive strains and host cytokine proinflammatory polymorphisms have been associated with gastric carcinoma. However, the individual role of each factor has not been evaluated yet. Our aim was to evaluate whether IL‐1 gene cluster and tumor necrosis factor‐α (TNFA)‐307 polymorphisms, as well as cagA‐positive status, are associated with gastric carcinoma in a non‐Caucasian population by analyzing the data in logistic regression models. We evaluated 166 patients with noncardia gastric carcinoma and 541 blood donors. Among them, 702 were successfully genotyped for all cytokine studied: 166 with gastric carcinoma and 536 controls. The carcinoma patients were considered to be H. pylori‐positive if culture alone or 2 among preformed urease test, stained smear or histologic section, serology, polymerase chain reaction (PCR) for ureA and urea breath test were positive. In blood donors, H. pylori status was based on enzyme‐linked immunosorbent assay. The cagA status was determined by PCR or serology. IL1B‐511/‐31, IL1RN (interleukin‐1 receptor antagonist) and TNFA‐307 polymorphisms were genotyped by PCR, PCR with restriction fragment length polymorphism, or PCR with confronting 2‐pair primers. We found that the IL1RN2 polymorphic allele (OR = 1.93) was associated with noncardia gastric carcinoma, even after inclusion of age, gender and cagA status in the logistic models. However, the cagA‐positive status was the strongest independent factor associated with gastric carcinoma (OR = 11.89). The other polymorphisms were not significantly associated with the disease when they were evaluated in logistic models. This study provides evidence supporting the independent associations of cagA‐positive H. pylori status and IL1RN polymorphisms with noncardia gastric carcinoma.

Helicobacter pylori Primary Resistance to Metronidazole and Clarithromycin in Brazil

ABSTRACT Helicobacter pylori resistance to metronidazole was detected in 107 (52.97%) of 202 strains. Twenty (9.85%) strains, 18 of them harboring 23S ribosomal DNA mutations, were resistant to clarithromycin. Metronidazole resistance was associated with female gender. Resistance to metronidazole and resistance to clarithromycin were associated. Increasing clarithromycin resistance rates were observed over time.

Helicobacter pylori infection in adults from a poor urban community in northeastern Brazil: demographic, lifestyle and environmental factors

We investigated the prevalence and the risk factors for infection with Helicobacter pylori in a randomly-selected population of adults from a low-income community in Northeastern Brazil. Helicobacter pylori infection was determined by ELISA. Risk factors were assessed using a structured interview. Two hundred and four individuals were included in the study, including 49 males and 155 females, ranging from 18 to 80 years old. Overall, 165 of 204 participants (80%) were H. pylori positive, without significant gender differences (p= 0.49). The infection rate was of 84.7% in subjects 18 to 30 years of age, increasing to 92% in subjects 46-60 years old. Above 60 years old, the prevalence decreased slightly. As a whole, the prevalence of infection did not increase significantly (p=0.147) with age. There were no significant differences in the prevalence of H. pylori infection, when patients were classified by age, smoking habit, educational level, alcohol consumption, the number of persons per room, the number of children per household, the number of adults per household, cup-sharing, household pets, toilet location, number of persons per bed and medical history of antibiotic and raw vegetable ingestion. In conclusion, no risk factors associated with infection was found in these adults, suggesting that the infection, even in a poor population, may be acquired predominantly during childhood; the relatively high prevalence that we observed may be more due to a cohort effect than to acquisition of infection during adulthood.

iceA Genotypes of Helicobacter pylori Strains Isolated from Brazilian Children and Adults

ABSTRACT Data concerning the geographic distribution of iceAalleles are scarce, and information on the association of the gene with the disease is rare and still controversial. Furthermore, no such study has been developed in Brazil, where duodenal ulcer and gastric adenocarcinoma are very common. We investigated, by PCR, the frequency of iceA alleles and cagA status inHelicobacter pylori strains isolated from 142 patients (62 children and 80 adults; 66 female; mean age, 30.0 years; age range, 3 to 78 years) with gastritis, duodenal ulcer, or gastric adenocarcinoma.iceA was identified in bacterium samples obtained from all patients. Eleven (7.7%) of them were infected with multiple strains. Among the patients with nonmixed infection, iceA2 allele was detected in 118 (90.1%). iceA2 allele was associated with ulcer (P = 0.02) and with carcinoma (P = 0.001). iceA2 amplicons of 229, 334, or 549 bp were detected, but none of them was associated with the patients disorder. iceA2 strains were more frequent in patients older than 7 years (P = 0.001). The gene was also more frequent in strains obtained from males (P = 0.02). cagA was more common in strains obtained from carcinoma (P = 0.0008) and ulcer patients (P < 0.006). cagA-positive strains were more frequent in children older than 7 years (P < 0.003). No association between cagA status and sex was found (P = 0.28). In conclusion, we thinkiceA should not be used as a reliable marker for predicting the clinical outcome of H. pylori infection.

Isolation of Helicobacter pylori from the Intestinal Mucosa of Patients with Crohn's Disease

Background:  Helicobacter species are associated with inflammatory bowel disease in rodents and in nonhuman primates. Therefore, we prospectively investigated the presence of Helicobacter species in the intestinal mucosa of patients with and without Crohns disease by culture and polymerase chain reaction (PCR) assays.