Biomedical subjects

C Neace

Publications and source records attributed to C Neace.

12 recordsLinked to original sources

PubMed2001

Reuse of negative CLOtest kits in children.

BACKGROUND: The rapid urease test, CLOtest, is used frequently in endoscopy suites. In the developed world, a negative CLOtest result is extremely common. The question of whether reuse of previously negative CLOtest kits is appropriate in children and the cost saving of such a practice were investigated. METHODS: Children who underwent diagnostic endoscopic procedures were prospectively recruited to the study. In each procedure gastric biopsy specimens were obtained for 2 rapid urease tests, one a new kit and the other a used negative kit obtained from previous procedures. In addition gastric specimens were also obtained for routine histologic examination. RESULTS: In 121 (99.2%) patients a complete concordance between new and used CLOtests was observed. Chi-square analyses showed a significant association between CLOtest results and each of the following factors: gastritis, the presence of Helicobacter pylori organisms, and H pylori-associated gastritis. Assuming an average rate of 15% positive CLOtest results in our pediatric population, the annual savings at the rural hospital was $265 and at the urban children's hospital, $1958. CONCLUSION: Reuse of a negative CLOtest is reliable and may reduce costs, especially in facilities with a high volume of endoscopic procedures.

Child↗

PubMed2000

Is sudden infant death syndrome associated with Helicobacter pylori infection in children?

Helicobacter pylori infection has recently been implicated in the pathogenesis of sudden infant death syndrome (SIDS). We investigated this association. Twenty-five pairs of gastric and tracheal tissue specimens obtained from autopsies of 25 children with previous diagnoses of SIDS were available for this study. The presence of H. pylori organisms was evaluated by three different methods: histology (hematoxylin-eosin or Giemsa staining), immunohistochemistry, and nested polymerase chain reaction technique. We were unable to confirm the presence of H. pylori organisms by the first two methods. H. pylori DNA was identified by nested polymerase chain reaction in six different tissue specimens (stomach, 4; trachea, 2). In no case was H. pylori DNA detected in both tissues. We concluded that H. pylori infection is most likely not associated with SIDS.

Female↗

PubMed1999

Tryosine kinase and ornithine decarboxylase activation in children with Helicobactor pylori gastritis.

H. pylori infection has been considered a risk factor for the development of gastric malignancy. Ornithine decarboxylase and tyrosine kinases activities are increased in patients with colon or esophageal cancer. In this study we compared the ODC and tyrosine kinases activities in the gastric mucosa of children with H. pylori infection and normal mucosa. Gastric biopsies were prospectively collected from children during routine upper endoscopic procedure. H. pylori infection was determined histologically. Biopsies were analyzed for ODC activity, total tyrosine kinases activities, and for the activity of protooncogene tyrosine kinase pp60(c-src). The mean ODC activity (pmol 14CO2/mg. protein/hr) and total tyrosine kinases activity (pmol 32P/mg. protein) were 186 and 5877 for H. pylori infected mucosa; and 229 and 4300, for normal mucosa, respectively (p> 0.05). Tyrosine kinase pp60(c-src) protein levels were similar between H. pylori infected mucosa and normal mucosa (3.12 and 2.15 pmol 32P/mg. protein, respectively; p>0.05). There was no correlation between gastric inflammation and the level of ODC or tyrosine kinase activities. ODC and tyrosine kinase activities in the gastric mucosa are similar in children with H. pylori infection compared to normal mucosa. The data suggest that these enzymes cannot be used as markers for future cancer development in children.

Adolescent↗

PubMed1999

Detection of Helicobacter pylori organisms by Hp-fast in children.

Hp-fast is a new rapid urease test (RUT) that has not been evaluated in children. The aim of the study was to prospectively compare the Hp-fast test to the CLOtest in children. Children with gastrointestinal symptoms who undergo diagnostic upper endoscopy were prospectively enrolled to the study. Antral gastric biopsies were evaluated for histology and for CLO-test and Hp-fast. Results were then compared to histology. Of the 94 children who participated, gastritis was found in 38 (40%), of whom 16 (42%) had associated H. pylori organisms. In two children, H. pylori organisms were identified without gastritis. The concordance between both RUT tests was 98%. A significant correlation was found between RUT results and histological factors or serology. The accuracy rate of both RUT increased significantly when different gold standards were utilized to detect Hp infection in children. The best correlation was found when histology and serology were considered as the gold standard for the diagnosis of H. pylori infection in children (sensitivity: 100% compared to 43-80% with other standards, respectively). In conclusion, the Hp-fast test result is comparable to CLOtest, but neither alone is sufficient to establish the diagnosis of Hp infection in children.

Adolescent↗

PubMed1999

Prevalence of CagA, VacA antibodies in symptomatic and asymptomatic children with Helicobacter pylori infection.

BACKGROUND: Limited data are available on the prevalence of CagA and VacA Helicobacter pylori antibodies in children. The aim of this study was to investigate the antibody prevalence to the H. pylori virulence factors CagA and VacA in symptomatic and asymptomatic children with H. pylori infection and to correlate these antibodies with the severity of gastric inflammation or density of H. pylori organisms in the gastric mucosa. MATERIALS AND METHODS: Twenty-three symptomatic children and 132 asymptomatic children with positive H. pylori serology participated in this study. Anti-H. pylori IgG antibody and CagA or VacA H. pylori antibodies were measured by enzyme immunoassay (HM-CAP; sensitivity and specificity > 90%) and Western immunoblot (Helicoblot 2.0) methods, respectively. Gastric inflammation and H. pylori density were graded histologically using the revised Sydney criteria. RESULTS: The prevalence of CagA and VacA antibodies were 69% and 35% in symptomatic children and 54% and 52% in asymptomatic children, respectively. Multiple regression analysis showed a correlation between CagA antibody and the severity of gastritis but no correlation with other histological features, including the number of neutrophils or lymphoid follicles. Neither antibody correlated with the degree of bacterial density in the gastric mucosa. CONCLUSION: CagA and VacA H. pylori antibodies are common in the pediatric population. The combined CagA/VacA antibodies correlated weakly with the degree of mucosal inflammation.

Adolescent↗

PubMed1999

Helicobacter pylori antibody profile in household members of children with H. pylori infection.

Intrafamilial spread is implicated as a major route for acquisition of Helicoobacter pylori infection. Investigating H. pylori cytotoxin-associated protein (CagA) and vacuolating toxin (VacA) antibodies within family members enabled the authors to evaluate this possibility further. Serum samples were collected prospectively from household members after their index children were diagnosed with active H. pylori infection. Serum samples were evaluated for anti-H. pylori immunoglobulin G antibody using the enzyme immunoassay (IEA) method and for H. pylori CagA and VacA antibodies with the commercially available immunoprobing Western blot kit. Ten different families participated in the study, including 10 pediatric patients and 31 household members. All patients and 28 household members (90%) were seropositive for H. pylori antibody by IEA and Western blot tests. Overall, 17 subjects (41.4%) were CagA positive, 14 (34.1%) were VacA positive, 11 (26.8%) were positive for both antibodies, and 22 (53.6%) were negative for both antibodies. A significant association in bacterial antibody profile was found between the patient index members and all household members (Cohen's kappa and Mentel-Haenszel methods). In four families, more than 66% of the household members harbored the same antibody profile, and in two families a completely different profile was observed. Moreover, a similar H. pylori antibody profile between the index patient and the mother was found in six families, and between the index patient and the father in two families. The data strongly suggest an intrafamiliar transmission for H. pylori infection.

Adult↗

PubMed1998

Immunosuppressive effect of budesonide on human lamina propria lymphocytes.

Budesonide, a beta-adreno-receptor agonist, is comparable to corticosteroid in the treatment of patients with inflammatory bowel disease with the advantage of minimal side effect. Although the immunomodulatory effects of budesonide on the circulatory and respiratory mucosal immune system have been reported, its effect on the human gut immune system has not been published. In this study, the effect of budesonide on the human gut immune system was compared to methyl-prednisolone. The cellular immune function was measured in-vitro by DNA synthesis, ornithine decarboxylase (ODC) activity and TNFalpha secretion. We found that both drugs have a comparable inhibitory effect on DNA synthesis, ODC activity and suppression of TNFalpha secretion. Exogenous addition of IL-2, did not restore the antiproliferative effect of both drugs. We conclude that budesonide has a comparative suppressive effect to methyl-prednisolone on the gut immune system which is not related to IL-2 secretion. The antiproliferative response may explain the therapeutic effect of budesonide on patients with inflammatory bowel disease.

Adrenergic beta-Agonists↗

PubMed1998

Prevalence of Helicobacter pylori infection in children from urban and rural West Virginia.

Our objective was to evaluate the prevalence rate of Helicobacter pylori (HP) in children from urban and rural areas of West Virginia. In all, 1164 blood samples were collected from children who attended a local health fair, pediatric clinics, and emergency departments of four different hospitals located in urban and rural counties. Socioeconomic status was determined in 303 children. Serum HP antibody (IgG) was measured by enzyme immunoassay (EIA). A total of 468 (40%) samples were HP positive. HP acquisition correlated with increasing age, family crowding, and community location (urban/rural) but not with gender, water source used (city/well), or socioeconomic status. The prevalence rate of HP in the children of West Virginia is higher than any data previously reported from the United States. The results correlated with only few socioeconomic criteria, suggesting that other factors may contribute to the increased prevalence of HP infection in the children of West Virginia.

Adolescent↗

PubMed1998

Human vaginal mucosal immune system: characterization and function.

OBJECTIVE: The mucosal immune system has been recognized as the first line of defense against foreign antigens. The limited information available on the mucosal immunity of the lower reproductive organs have restricted our ability to fight infections, especially, the sexually transmitted disease. The aim of this study was to characterize in-vitro the human vaginal lamina propria lymphocytes (VLPL), their cell surface phenotypes, and cellular function. METHODS: VLPL were isolated from human vaginal mucosa by enzymatic techniques. Cell surface characteristics were investigated by immunohistochemistry and flow cytometric analysis. Cellular immune function was evaluated by 3H-thymidine incorporation studies and ornithine decarboxylase (ODC) activity. RESULTS: Immunohistochemistry and flow cytometric analysis showed that the CD4/CD8 ratio of the human vaginal mucosa is reversed compared to the gut lamina propria lymphocytes (0.55 +/- 0.17). PHA and ConA mitogens enhanced VLPL thymidine incorporation, while PWM did not have any significant effect. Very high level of ODC activity was observed in VLPL after PHA stimulation. CONCLUSIONS: The human VLPL can be isolated, characterized, and respond to a mitogenic stimulus. We postulate that further analysis of the vaginal immune system will enhance our understanding of local defence mechanisms which will help in the development of new therapeutic modalities against vaginal infections.

CD4-CD8 Ratio↗

PubMed1997

Vitamin A and retinoic acids immunomodulation on human gut lymphocytes.

Epidemiological studies have suggested an important immunomodulatory role for vitamin A and other related vitamin A compounds in adults and children. Although vitamin A is absorbed via the gastrointestinal tract, its affect on the gut mucosal immune cells has not been adequately investigated. We investigated the in-vitro effect of vitamin A (retinol) and its retinoid acid (RA) compounds (13-cis- and all trans-retinoic acids) on the human gut mucosal immune system as represented by colonic lamina propria lymphocyte (LPL) proliferation, and ornithine decarboxylase (ODC) activity. Results showed that retinol suppressed and trans-retinoic acid enhanced thymidine incorporation into LPL. 13-cis retinoic acid did not significantly affect LPL DNA synthesis. Similarly, retinol (0.025 microgram/ml and 10 micrograms/ml) and 13-cis retinoic acid (conc. 10 micrograms/m) suppressed, while all trans-retinoic acid (conc. 10 micrograms/ml) enhanced ODC activity in PHA-stimulated LPL. Interestingly, the effects of retinol and all trans-RA were abolished when LPL were previously depleted of macrophages. Addition of monocyte-associated lymphokines, IL-1 and IL-6, showed that IL-1 partially replaced the enhancing effect of all trans-RA previously observed on LPL thymidine incorporation. IL-6 did not affect LPL DNA synthesis irrespective of the vitamin A compound used. We conclude that retinol and retinoid acids (13-cis, all trans-) may alter the human colonic immune system possibly via IL-1 cytokine, but not via IL-6. The data suggest that vitamin A and its retinoid compounds may participate in the modulation of the gut immune system.

Adjuvants, Immunologic↗

PubMed1997

Comparison between a rapid office-based and ELISA serologic test in screening for Helicobacter pylori in children.

BACKGROUND: The rapid diagnostic serological test for detection of Helicobacter pylori (H. pylori) infection in children has a significant advantage over the standard enzyme immunoassay (EIA) method, for its simplicity and rapid availability of results in a physician's office setting. We compared the immunochromatographic test with a standard enzyme immunoassay test in the pediatric population. MATERIALS AND METHODS: A retrospective analysis of 1147 serum samples from asymptomatic children and prospective analysis of 62 serum samples from symptomatic children undergoing diagnostic upper endoscopy were evaluated for the detection of H. pylori antibody by two commercially available serology tests. Each serum sample was tested by a rapid test (FlexSure HP, SmithKline Diagnostics, Inc.) and compared to the standard EIA method (HM-CAP, Enteric Products, Inc.). RESULTS: The rapid test, FlexSure HP, was comparable to the rapid EIA test in screening for H. pylori infection in symptomatic and asymptomatic children with sensitivity and specificity of 83-90% and 90-100%, respectively. Both methods had a comparable sensitivity and specificity for the detection of H. pylori-associated gastritis (60-70% and 94%, respectively). CONCLUSION: The rapid test is comparable to the standard EIA test and may be used by physicians in symptomatic children. The use of FlexSure HP as a screening tool for the prevalence of H. pylori infection in asymptomatic children may be limited by its low positive predictive value compared to the EIA method.

Adolescent↗

PubMedDate not supplied

Helicobacter pylori serology and the diagnosis of H. pylori infection in children.

Serological screening accuracy rate may be dependent on clinical and pathological determinants. The aim of this study was to evaluate the accuracy of Hp serology test (Roche Biomedical Lab., Labcorp), in the diagnosis of Hp infection in 121 children who were seen in the Pediatric Gastoenterology Clinic at the Marshall University Joan C. Edwards School of Medicine in Huntington. Positive serology detected children with Hp-associated gastritis with a sensitivity of 51.6%. Positive serology significantly correlated with the degree of gastric inflammation and density of Hp organisms in the gastric mucosa (ANOVA p < 0.001). The Labcorp. Hp-ELISA test had a poor accuracy rate for the detection of Hp-gastritis in children. Gastric biopsies should always be performed to establish the diagnosis of Hp infection in children.

Adolescent↗