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Publication
Journal: Journal of Clinical Pathology
September/11/2006
Abstract
BACKGROUND
Screening for IgA deficiency in patients with coeliac disease is essential because of the increased incidence of IgA deficiency associated with the disease, which usually relies on the estimation of IgA levels in each case.
OBJECTIVE
To devise a method of excluding IgA deficiency without measuring total serum IgA in each case.
METHODS
The optical density readings on enzyme-linked immunosorbent assay (ELISA) of 608 routine samples received for tissue transglutaminase (TTG) antibody testing for coeliac disease were compared with their total IgA concentrations. Dilution experiments were also carried out to ensure linear relationships between optical density on ELISA and IgA concentrations and to compare the sensitivities for TTG and endomysium antibodies in TTG-positive samples.
CONCLUSIONS
A clear relationship was shown between total IgA concentration and TTG optical density readings by ELISA. To ensure a positive TTG result if antibodies are present, it was possible to recommend an optical density level above which all samples have sufficient IgA. Samples with optical density <0.05 should be investigated further by estimating total IgA and, if low, samples should be subjected to immunofluorescence microscopy testing for IgA and IgG endomysium antibodies.
CONCLUSIONS
An easier, more cost-effective and practical way of excluding IgA deficiency in the investigation on coeliac disease is reported.
Publication
Journal: Clinical Chemistry and Laboratory Medicine
September/27/2012
Abstract
BACKGROUND
In the diagnosis of celiac disease (CD), serum assays for anti-endomysium (EMA) and anti-transglutaminase (anti-tTG) antibodies have excellent diagnostic accuracy. However, these assays are less sensitive in young pediatric patients. Recently, a new ELISA test using deamidated gliadin peptides (DGP) as antigen has proved to be very sensitive and specific even in pediatric patients. In addition, anti-actin IgA antibodies (AAA) is another test that can be used in CD patients because antibody concentrations correlate with the degree of villous atrophy. This study evaluated the clinical accuracy of anti-tTG, EMA, AGA, anti-DGP and AAA and the effectiveness of these in different combinations for diagnosing CD in a large cohort of pediatric patients.
METHODS
Sera of 150 children under 6 years of age were tested: 95 patients had a diagnosis of CD, while 55 patients who did not suffer from CD were used as controls. Anti-DGP IgA/IgG and AAA were assayed with ELISA kits, while anti-tTG IgA/IgG and AGA IgG/IgA were assayed using a quantitative fluoroimmunoassay. The EMA test was conducted by indirect immunofluorescence.
RESULTS
Seventy-six of 95 (80%) CD patients were positive for DGP IgA and/or tTG IgA. Eighty of 95 (84.2%) patients were positive for DGP IgG and/or tTG IgA. None of the controls were positive for these antibodies. Eighty-four of 95 (88.4%) patients and 8/55 (14.5%) controls were positive for AAA and/or anti-tTG IgA.
CONCLUSIONS
In very young children, association of anti-tTG IgA with anti-DGP IgG is the best test combination for diagnosing CD, yielding a cumulative sensitivity of 84.2% and a specificity of 100%.
Publication
Journal: Nutrients
August/20/2019
Abstract
Two Lactobacillus strains have proven anti-inflammatory properties by reducing pro-inflammatory responses to antigens. This randomized double-blind placebo-controlled trial tested the hypothesis that L. plantarum HEAL9 and L. paracasei 8700:2 suppress ongoing celiac disease autoimmunity in genetically at risk children on a gluten-containing diet in a longitudinally screening study for celiac disease. Seventy-eight children with celiac disease autoimmunity participated of whom 40 received 1010 CFU/day of L. plantarum HEAL9 and L. paracasei 8700:2 (probiotic group) and 38 children maltodextrin (placebo group) for six months. Blood samples were drawn at zero, three and six months and phenotyping of peripheral blood lymphocytes and IgA and IgG autoantibodies against tissue transglutaminase (tTG) were measured. In the placebo group, naïve CD45RA+ Th cells decreased (p = 0.002) whereas effector and memory CD45RO+ Th cells increased (p = 0.003). In contrast, populations of cells expressing CD4+CD25highCD45RO+CCR4+ increased in the placebo group (p = 0.001). Changes between the groups were observed for NK cells (p = 0.038) and NKT cells (p = 0.008). Median levels of IgA-tTG decreased more significantly over time in the probiotic (p = 0.013) than in the placebo (p = 0.043) group whereas the opposite was true for IgG-tTG (p = 0.062 respective p = 0.008). In conclusion, daily oral administration of L. plantarum HEAL9 and L. paracasei 8700:2 modulate the peripheral immune response in children with celiac disease autoimmunity.
Publication
Journal: Clinical Chemistry and Laboratory Medicine
July/10/2016
Abstract
BACKGROUND
The European Society for Pediatric Gastroenterology and Nutrition states that if IgA anti-tissue transglutaminase (tTG) exceeds 10 times the upper limit of normal (ULN), there is the possibility to diagnose celiac disease (CD) without duodenal biopsy, if supported by anti-endomysium testing and human leukocyte antigen (HLA) typing. We aimed to evaluate whether combining IgA tTG and IgG anti-deamidated gliadin peptide (DGP) antibody testing and taking into account the antibody levels improves clinical interpretation.
METHODS
We calculated likelihood ratios for various test result combinations using data obtained from newly diagnosed CD patients (n=156) [13 children <2 years, 45 children between 2 and 16 years, and 98 adults (>16 years)] and 974 disease controls. All patients and controls underwent duodenal biopsy. IgA anti-tTG and IgG anti-DGP assays were from Thermo Fisher and Inova.
RESULTS
Likelihood ratios for CD markedly increased with double positivity and increasing antibody levels of IgA anti-tTG and IgG anti-DGP. Patients with double positivity and high antibody levels (>3 times, >10 times ULN) had a high probability for having CD (likelihood ratio ≥649 for >3 times ULN and ∞ for >10 times ULN). The fraction of CD patients with double positivity and high antibody levels was 59%-67% (depending on the assay) for >3 ULN and 33%-36% (depending on the assay) for >10 ULN, respectively. This fraction was significantly higher in children with CD than in adults.
CONCLUSIONS
Combining IgG anti-DGP with IgA anti-tTG and defining thresholds for antibody levels improves the serologic diagnosis of CD.
Publication
Journal: American Journal of Gastroenterology
June/19/2017
Abstract
Response to gluten challenge (GC) is a key feature in diagnostic algorithms and research trials in celiac disease (CD). Currently, autoantibody titers, late responders to GC, and invasive duodenal biopsies are used to evaluate gluten responsiveness. This study investigated the accuracy of serum intestinal-fatty acid binding protein (I-FABP), a marker for intestinal epithelial damage, to predict intestinal damage during GC in patients with CD.
Twenty adult CD patients in remission underwent a two-week GC with 3 or 7.5 g of gluten daily. Study visits occurred at day -14, 0, 3, 7, 14, and 28. Serum I-FABP, antibodies to tissue transglutaminase (tTG-IgA), deamidated gliadin peptides (IgA-DGP), and anti-actin (AAA-IgA) were assessed at each visit. Villous-height to crypt-depth ratio (Vh:Cd) and intraepithelial lymphocyte (IEL) count were evaluated at day -14, 3, and 14. Forty-three CD-serology negative individuals were included to compare serum I-FABP levels in CD patients on a gluten-free diet (GFD) with those in healthy subjects.
Serum I-FABP levels increased significantly during a two-week GC. In contrast, the most pronounced autoantibody increase was found at day 28, when patients had already returned to a GFD for two weeks. IgA-AAA titers were only significantly elevated at day 28. I-FABP levels and IEL count correlated at baseline (r=0.458, P=0.042) and at day 14 (r=0.654, P=0.002) of GC. Neither gluten dose nor time on a GFD influenced I-FABP change during GC.
Serum I-FABP levels increased significantly during a two-week GC in adult CD patients and correlated with IEL count. The data suggest that serum I-FABP is an early marker of gluten-induced enteropathy in celiac patients and may be of use in both clinical and research settings.
Publication
Journal: Journal of Pediatric Gastroenterology and Nutrition
June/30/2013
Abstract
OBJECTIVE
Although it is well known that celiac disease (CD) is associated with neurologic disorders, association with psychiatric problems is not well defined. In this report, we aimed to detect CD prevalence in patients with attention-deficit hyperactivity disorder (ADHD).
METHODS
A total of 362 patients between the ages 5 and 15 years with the diagnosis of ADHD according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) diagnostic criteria and 390 sex- and age-matched healthy children were included in the present study. Serum levels of tissue transglutaminase (tTg) immunoglobulin (Ig) A and IgG were studied in both groups. Serum IgA levels were also studied in patients with positive tTG IgG for the exclusion of selective IgA deficiency. Endoscopic duodenal biopsy was provided in seropositive patients, whose parents approved the procedure. Biopsy samples were evaluated according to Marsh-Oberhuber classification.
RESULTS
tTg IgA was positive in 4 patients with ADHD (1.1%). Endoscopic duodenal biopsy was suggestive of CD in one of them (0.27%). tTg IgA was positive in 3 of control group patients (0.8%). Duodenal biopsy of the only patient from control group, who underwent upper gastrointestinal endoscopy, revealed normal intestinal mucosa.
CONCLUSIONS
The seropositivity rates for CD were found similar in ADHD and control groups. Thus, neither routine screening for CD nor empirical recommendation of gluten-free diet seems necessary in children with ADHD.
Publication
Journal: Medicine
February/10/2016
Abstract
Celiac disease (CD) is common in Caucasians, but thought to be rare in Asians. Our aim was to determine the prevalence of CD in Chinese patients with chronic diarrhea predominant irritable bowel syndrome (IBS-D).From July 2010 to August 2012, 395 adult patients with IBS-D and 363 age and sex-matched healthy controls were recruited in Zhongnan Hospital of Wuhan University and Xiaogan Central Hospital in Hubei province, central China. Patients with IBS-D were diagnosed according to the Rome III criteria. Serum Immunoglobulin (IgA/IgG) anti-human tissue transglutaminase (anti-htTG)-deamidated gliadin peptide (DGP) antibodies were measured in a single ELISA (QUANTA Lite h-tTG/DGP Screen). Upper endoscopy with duodenal biopsies and HLA-DQA1 and HLA-DQB1 genotyping were performed in seropositive subjects and a gluten-free diet was prescribed.Seven IBS-D patients (7/395, 1.77%) and 2 healthy controls (2/363, 0.55%), were positive for anti-htTG/DGP antibodies. Of these 9 cases, 1 was lost to follow-up, 3 were suspected to have CD and 5 were eventually diagnosed as CD with intestinal histological lesions classified as Marsh Type II in 2 and Type III in 3. Of these 5 diagnosed CD patients, 4 (4/395, 1.01%) were from the IBS-D group and 1 (1/363, 0.28%) from the healthy control had asymptomatic CD. Two Type III CD patients with relatively high titers in the serologic assay were homozygous and heterozygous for haplotype HLA-DQA1*03-DQB1*03:03 (HLA-DQ9.3), respectively.In the present study, CD was present in 1.01% of patients with IBS-D and in 0.28% of the control group. We like to suggest that the haplotype HLA-DQA1*03-DQB1*03:03 (HLA-DQ9.3), which is common in Chinese, is a new susceptibility factor for CD in China. Larger screening and genetic studies are needed in the Chinese population of different regions.
Publication
Journal: Microbial Drug Resistance
February/16/2016
Abstract
OBJECTIVE
Tuberculosis (TB) is a devastating infectious disease causing high mortality and morbidity worldwide. The most serious threat related to tuberculosis control is the recent emergence of drug-resistant tuberculosis strains. The aim of the present study was to identify various types of mutations in the rpoB region in rifampicin-resistant strains isolated from sputum of tuberculosis patients.
METHODS
Drug susceptibility of 125 Mycobacterium tuberculosis isolates was determined using the CDC standard conventional proportional method. Target DNA of M. tuberculosis was amplified by polymerase chain reaction, hybridized, and scanned. We used the low cost density array (LCD-array) to detect mutations within the 90-bp rpoB region. Each array is a transparent, prestructured polymer support using a nonfluorescent detection principle based on the precipitation of a clearly visible dark substrate.
RESULTS
Of the 125 M. tuberculosis isolates, 35 (28%) were found to be rifampicin-resistant and using the LCD array revealed point mutations at nine different codons as follows: S512T (AGC→ACC) (20%), D516V (GAC→GTC) (20%), H526D (CAC→GAC) (6%), H526R (CAC→CGC) (20%), H526Y (CAC→TAC) (23%), and S531W (TCG→TGG) (8%), and the most frequent site mutations were L511P (CCG→CTG) (46%), followed by S531l (TCG→TTG) (40%) and D516Y (GAC→TAC) (26%).
CONCLUSIONS
Our data significantly differs from previously reported mutation frequencies for codon 526 (CAC to GAC) among Italian isolates (40.1%) and Greek isolates (17.6%). Phenotypic testing is time-consuming and requires laboratory resources. Microarray rpoB is useful in detecting rifampicin resistance-determining region-associated site mutations of rifampicin-resistant M. tuberculosis isolates.
Publication
Journal: American Journal of Gastroenterology
June/19/2017
Abstract
Celiac disease (CD) and irritable bowel syndrome (IBS) share similar symptoms, leading to confusion between the two and diagnostic delay. International guidelines recommend screening individuals with IBS for CD, via serological testing. However, studies published recently have cast doubt on the utility of this. We updated a previous meta-analysis examining this issue.
MEDLINE, EMBASE, and EMBASE Classic were searched through to May 2016. Eligible studies recruited adults with IBS according to symptom-based criteria, physician's opinion, or questionnaire data. Tests for CD included IgA-class antigliadin antibodies (AGA), endomysial antibodies (EMA), tissue transglutaminase antibodies (tTG), or duodenal biopsies following positive serology. The proportion of individuals meeting criteria for IBS testing positive for CD was combined to give a pooled prevalence for all studies, and compared between cases with IBS and, healthy controls without (where reported), using an odds ratio (OR) with a 95% confidence interval (CI).
There were 36 eligible studies, recruiting 15,256 individuals, of whom 9,275 (60.8%) met criteria for IBS. Pooled ORs for positive IgA AGAs, EMA and/or tTG, and biopsy-proven CD in IBS subjects vs. controls were 3.21 (95% CI 1.55-6.65), 2.75 (95% CI 1.35-5.61), and 4.48 (95% CI 2.33-8.60), respectively. There was no increase in ORs for any test for CD among cases with IBS in North American studies, and results were inconsistent in population-based studies. The prevalence of biopsy-proven CD was significantly higher across all subtypes of IBS. Limitations included heterogeneity in some analyses, and few North American studies.
Overall, prevalence of positive celiac serology and biopsy-proven CD was significantly higher in subjects with symptoms suggestive of IBS vs. healthy controls. However, the utility of screening for CD in individuals with suspected IBS in North America or in the community is less clear.
Publication
Journal: The Application of Clinical Genetics
November/3/2013
Abstract
OBJECTIVE
The aim of this study was to investigate the association of the Pro12Ala polymorphism of the human peroxisome proliferator-activated receptor gamma 2 (PPARγ2) gene with hypertension and obesity in a highly consanguineous aboriginal Qatari population.
METHODS
A cross-sectional survey conducted from January 2011-December 2012.
METHODS
Primary health care clinics.
METHODS
A random sample of 1,528 Qatari male and female population older than 20 years of age.
METHODS
Data on age, sex, income, level of education, occupation status, body mass index, and blood pressure and lipid profile were obtained. The Pro12Ala in the PPARγ2 gene was detected on the LightCycler® using two specific probes: (Sensor [G] 5'-CTC CTA TTG ACG CAG AAA GCG-FL and PPAR Anchor 5' LC Red 640- TCC TTC ACT GAT ACA CTG TCT GCA AAC ATA TC-PH). Univariate and multivariate logistic regression were performed.
RESULTS
Out of a total 1,528 participants, 220 were diagnosed with essential hypertension, and 420 were obese. Participants with consanguinity were significantly higher among hypertensive than normotensive (41.9% versus 30.8%; P=0.001). Altogether, more than three-fourths (89%) of the participants had a wild genotype (Pro12Pro), 9.8% were heterozygous with Pro12Ala, and only 1.2% was homozygous with the Ala12Ala genotype. The frequency of the Pro allele was 94.5% in normotensive versus 90.5% in hypertensive, while the distribution of the Ala allele was 5.5% in normotensive versus 9.5% in the hypertensive group (P=0.001). The odds of hypertension were 1.7 times higher among the participants with the Ala allele as compared to those with the Pro, while adjusting for other potential confounders (adjusted odds ratio 1.69; 95% confidence interval 1.12-2.55; P=0.012). There was no association between the PPARγ2Ala allele and obesity (P=0.740).
CONCLUSIONS
The current study revealed an association between the PPARγ2Ala allele and hypertension in Qatar's population. On the other hand, this study found no association between the Ala allele and obesity.
Publication
Journal: Journal of Pediatric Gastroenterology and Nutrition
November/18/2012
Abstract
OBJECTIVE
The aim of the study was to analyze the diagnostic performance of anti-deamidated gliadin peptide (dGp) immunoglobulin (Ig) G and IgA regarding the age at celiac disease (CD) diagnosis and the anti-dGp IgG usefulness for diagnosing CD IgA-deficient patients.
METHODS
Anti-dGp IgG and IgA and anti-native gliadin (nGlia) IgA were determined by enzyme fluoroimmunoassay in 100 newly diagnosed anti-tissue transglutaminase (tTG) IgA-positive pediatric and adult patients with CD and in 100 age-matched patients with other digestive pathologies. Anti-dGp IgG was evaluated in 6 CD IgA-deficient patients.
RESULTS
When analyzing all of the patients, the anti-dGp IgG assay showed higher diagnostic accuracy (area under receiver operating characteristic curve), specificity, and positive predictive value than anti-dGp IgA and anti-nGlia IgA. All of the diagnostic parameters corresponding to anti-dGp IgG reached the same values as anti-tTG IgA in children 7 years or younger. In older patients, both anti-dGp isotypes showed an inverse behavior, IgG having a higher specificity and positive predictive value but a lower sensitivity and negative predictive value than IgA. Anti-dGp levels were associated with the severity of intestinal lesions, and an inverse association was found regarding age at diagnosis. Both anti-dGp IgG and IgA were found to be positive in the 9 patients with minimal intestinal changes included in the study. All of the patients with CD with IgA deficiency were positive for anti-dGp IgG.
CONCLUSIONS
The diagnostic performance of anti-dGp depends on the antibody isotype and on the age at CD diagnosis, anti-dGp IgG being a serological marker at least as useful as anti-tTG IgA for detecting CD in children ages 7 years or younger. Our data also indicate that anti-dGp IgG can improve the diagnosis of IgA-deficient patients.
Publication
Journal: BMJ Open
February/19/2017
Abstract
The prevalence of coeliac disease (CD) in Vietnam is unknown. To fill this void, we assessed the prevalence of serological markers of CD autoimmunity in a population of children in Hanoi.
The outpatient blood drawing laboratory of the largest paediatric hospital in North Vietnam was used for the study, which was part of an international project of collaboration between Italy and Vietnam.
Children having blood drawn for any reason were included. Exclusion criteria were age younger than 2 years, acquired or congenital immune deficiency and inadequate sample. A total of 1961 children (96%) were enrolled (838 females, 1123 males, median age 5.3 years).
Primary outcome was the prevalence of positive autoimmunity to both IgA antitransglutaminase antibodies (anti-tTG) assessed with an ELISA test and antiendomysial antibodies (EMA). Secondary outcome was the prevalence of CD predisposing human leucocyte antigens (HLA) (HLA DQ2/8) in the positive children and in a random group of samples negative for IgA anti-tTG.
The IgA anti-tTG test was positive in 21/1961 (1%; 95% CI 0.61% to 1.53%); however, EMA antibodies were negative in all. HLA DQ2/8 was present in 7/21 (33%; 95% CI 14.5% to 56.9%) of the anti-tTG-positive children and in 72/275 (26%; 95% CI 21% to 32%) of those who were negative.
Coeliac autoimmunity is rare in Vietnam, although prevalence of HLA DQ2/8 is similar to that of other countries. We hypothesise that the scarce exposure to gluten could be responsible for these findings.
Publication
Journal: Gastroenterology Research and Practice
July/13/2011
Abstract
Objective. The prevalence of Celiac Disease (CD) is high in Iran, and evaluation of CD is not part of the routine screening procedure for dyspeptic patients; therefore, cases of occult CD may be missed. This study aimed to investigate the prevalence of occult CD among dyspeptic patients who presented at a gastroenterology clinic in the Western region of Iran. Methods. In this descriptive, cross-sectional prospective study, patients who had a history of at least 12 weeks of upper abdominal discomfort were eligible to participate in the study during a 14-month recruitment period. Patients with a clinical or paraclinical data in favor of organic causes were excluded from the study. Enrolled patients were screened for IgA antiendomysium antibody (EMA) and IgA antitissue transglutaminase antibody (tTG). Those who screened positive for EMA/tTG received a confirmatory diagnostic biopsy for Marsh classification of CD. Results. From 225 potential participants with dyspepsia, 55 patients were excluded due to having explainable organic causes. The study sample included 170 patients with "functional dyspepsia." Mean age of participants was 31 years and 55.8% were female. Twelve patients (7%) had positive tests (EMA/tTG), of which 10 were female (83.4%). According to Rome II criteria, all twelve patients with positive tests had "dysmotility type dyspepsia." Based on Marsh classification, six patients were consistent with "Marsh I," four with "Marsh II," and two with the "Marsh III" classification. Conclusions. In this study, the prevalence of CD in dyspeptic patients was high. As a result, this study suggests that screening by serology tests (EMA/tTG) is justifiable for the detection of CD among functional dyspeptic patients in the tertiary centers in our country.
Publication
Journal: Journal of Clinical Gastroenterology
March/31/2008
Abstract
OBJECTIVE
To prospectively evaluate the role of tissue transglutaminase (tTG) antibody in detecting celiac disease (CD) in Indian children.
METHODS
Over a period of 3 years, 333 children (<or=14 y of age) with suspected CD were evaluated. CD was diagnosed on the basis of modified ESPGHAN criteria. Antibody to <em>tTG</em> (guinea-pig) was detected by commercial enzyme-linked immunosorbent assay kit. Children with a suspicion of CD but found to have normal villous architecture were taken as controls. Antiendomysial antibody (EMA) and IgA-antigliadin antibody were done in 80 cases and 40 controls.
RESULTS
The mean age of 180 children with CD was 6.5+/-3 years with a male to female ratio of 1.7:1. Their presenting complaints were diarrhea in 84% and failure to thrive in 87%. Wasting, stunting, and anemia were seen in 87%, 59%, and 83% of cases, respectively. The best sensitivity and specificity of tTG antibody we have got at a cut-off value of 10 U/mL and were 94% and 97%, respectively, with a positive predictive value of 98% and negative predictive value of 92.4%. The mean tTG antibody titer was 106+/-76 U/mL in cases and 2+/-1.6 U/mL in controls (P<0.001). The concordance of tTG antibody with EMA was 95% in cases and 97.5% in controls.
CONCLUSIONS
tTG antibody is a highly sensitive and specific serologic marker. Being technically simpler and due to its high concordance with EMA, it can be used as an alternative to EMA in developing countries like India.
Publication
Journal: Differentiation
September/28/1994
Abstract
Rat pregnancy is characterized by a progressive continuous induction of apoptosis in the maternal tissues lining the conceptus. Different cell types (decidual cells, giant cells, epithelial cells, etc.) undergo apoptosis at the different stages of development. We demonstrated here that, independently from their origin and stage of pregnancy, the dying cells were invariably characterized by the presence of 'tissue' transglutaminase (tTG) and negligible amounts of Bcl-2 proteins. This finding confirms the antithetic roles played by these two gene products within the apoptotic pathway. It is noteworthy that Bcl-2 was detected in decidual cells just after the implant; however, starting from day 9, its positive detection was reduced in the maternal tissues and appeared in the embryonal ones. The apoptotic nature of death was also suggested by the presence of a high phagocytic activity in the maternal involuting regions and by morphological observations showing that the tTG positive cell remnants displayed typical phenotypic features of apoptosis. The possibility that the cells lining the conceptus that die by apoptosis could be envisaged as an inert barrier between the maternal and fetal tissues is discussed.
Publication
Journal: Mycoses
August/8/2001
Abstract
Twenty-five culture collection strains from four Aspergillus species (A. fumigatus n = 8, A. flavus n = 8, A. niger n = 4, A. nidulans n = 5) were characterized by four methods: (i) determination of patterns in an assimilation assay; (ii) protein pattern of whole mycelial cell lysates in the sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis (PAGE); (iii) reactivity of a pool serum obtained from cystic fibrosis patients with mycelial lysates in the immunoblot; and (iv) random amplification of polymorphic DNA (RAPD) with eight primers having arbitrary or repetitive sequences. In the assimilation assay the A. fumigatus strains showed identical patterns in contrast to the strains of the species A. flavus, A. niger, and A. nidulans, which each showed four patterns. In the SDS-PAGE no differences in the band patterns in the A. fumigatus strains were found, in contrast to the A. flavus (three patterns), A. nidulans (five patterns) and A. niger strains (two patterns). The immunoblot patterns were characteristic for each species with bands at 62 and 17/18 kDa in the A. fumigatus strains, at 51 and 18 kDa in the A. flavus strains, at 51 kDa in the A. niger strains, and at 51, 40 and 17/18 kDa in the A. nidulans strains allowing, however, no intraspecies typing. In the RAPD assay four out of eight primers gave interpretable patterns with 3-20 bands. None of the primers showed sufficient discriminatory power when used alone. However, when combining the results of two of the primers (5'-GTA TTG CCC T-3' and 5'-GAT AGA TAG ATA GAT A-3') all strains except two A. fumigatus strains could be clearly separated from each other. It is concluded that the the RAPD assay showed the most discriminatory power in all Aspergillus species investigated. In contrast to the phenotypically similar A. fumigatus strains, the strains of the species A. flavus, A. nidulans and A. niger differed in their phenotypic characteristics. The presented data of strains from international culture collections may serve as basis for interlaboratory standardization of typing methods.
Authors
Publication
Journal: Annals of Allergy, Asthma and Immunology
August/6/2014
Abstract
BACKGROUND
Tissue transglutaminase (tTG) is a post-translational modifying enzyme located in airway epithelial cells. A potential contribution of serum specific IgG (sIgG) to tTG in airway inflammation of toluene diisocyanate (TDI)-induced occupational asthma (OA) has been suggested.
OBJECTIVE
To prepare a TDI-tTG conjugate and detect serum specific antibodies in sera of patients with TDI-OA to understand this mechanism.
METHODS
Ninety-nine patients with TDI-OA, 76 asymptomatic exposed controls, 208 patients with non-OA, and 74 unexposed controls were enrolled for this study. The TDI-tTG conjugate was prepared and confirmed by a native gel. Serum sIgG and/or sIgE antibodies to tTG, TDI-tTG, TDI conjugated to human serum albumin, cytokeratin 19, and serum cytokine levels, such as interleukin-8, transforming growth factor-β1, and tissue inhibitor of metalloproteinase-1, were measured by enzyme-linked immunosorbent assay. The level of interleukin-8 produced from airway epithelial cells (A549) treated with tTG was evaluated to investigate the inflammatory effect of tTG and TDI-tTG.
RESULTS
In the TDI-OA group, the prevalence of serum sIgG to TDI-tTG (17.2%) was higher than that of sIgG to tTG (11.1%), which were significantly higher than those of the 3 control groups (P < .05 for all groups). TDI-exposed subjects with high levels of serum sIgG to TDI-tTG had a high prevalence of sIgG to cytokeratin 19 and higher serum levels of transforming growth factor-β1 and tissue inhibitor of metalloproteinase-1. The tTG and TDI-tTG dose-dependently increased interleukin-8 production from A549 cells.
CONCLUSIONS
These findings suggest that TDI exposure in the workplace binds to tTG to form a conjugate that can induce serum sIgG antibody production, airway inflammation, and airway remodeling in patients with TDI-OA.
Publication
Journal: Lipids in Health and Disease
November/25/2014
Abstract
BACKGROUND
Apolipoprotein A1 (ApoA1) is the major apoprotein constituent of high density lipoprotein (HDL) which exerts innate protective effects in systemic inflammation. However, its role in the acute lung injury (ALI) has not been well studied. In the present study we investigated the association between polymorphisms of ApoA1 gene and ALI in a Chinese population.
METHODS
Three polymorphisms of the ApoA1 gene (rs11216153, rs2070665, and rs632153) were genotyped by TaqMan method in 290 patients with sepsis-associated ALI, 285 patients sepsis alone and 330 age- and sex-matched healthy controls.
RESULTS
We found rs11216153 polymorphism of ApoA1 was associated with ALI, the GG genotype and G allele was common in the ALI patients (76.9%, 88.1%, respectively) than both in the control subjects (55.8%, 75.8%, respectively) and in the sepsis alone patients (58.2%, 78.4%, respectively). Haplotype consisting of these three SNPs strengthened the association with ALI susceptibility. The frequency of haplotype GTG in the ALI samples was significantly higher than that in the healthy control group (OR = 2.261, 95% CI: 1.735 ~ 2.946, P <0.001) and the sepsis alone group (OR = 1.789, 95% CI: 1.373 ~ 2.331.P < 0.001). Carriers of the haplotype TTG had a lower risk for ALI compared with healthy control group (OR = 0.422, 95% CI: 0.310 ~ 0.574, P < 0.001) and sepsis alone group (OR = 0.491, 95% CI: 0.356 ~ 0.676, P <0.001).
CONCLUSIONS
These results indicated that genetic variants in the ApoA1 gene might be associated with susceptibility to sepsis-associated ALI in Han Chinese population.
Publication
Journal: Brain research. Molecular brain research
July/24/2005
Abstract
Tissue transglutaminase (tTG) is a member of a multigene family principally involved in catalyzing the formation of protein cross-links. Unlike other members of the transglutaminase family, tTG is multifunctional since it also serves as a guanosine triphosphate (GTP) binding protein (Galpha(h)) and participates in cell adhesion. Different isoforms of tTG can be produced by proteolysis or alternative splicing. We find that tTG mRNA is expressed at low levels in the mouse CNS relative to other tissues, and at lower levels in the CNS of mouse in comparison to that of human or rat. tTG mRNA levels are higher in the heart compared to the CNS, for example, and much higher in the liver. Within the CNS, tTG message is lowest in the adult cerebellum and thalamus and highest in the frontal cortex and striatum. In the hippocampus, tTG expression is highest during embryonic development and falls off dramatically after 1 week of life. We did not find alternative splicing of the mouse tTG. At the protein level, the predominant isoform is approximately 62 kDa. In summary, tTG, an important factor in neuronal survival, is expressed at low levels in the mouse CNS and, unlike rat and human tTG, does not appear to be regulated by alternative splicing. These findings have implications for analyses of rodent tTG expression in human neurodegenerative and neurotrauma models where alternative processing may be an attractive pathogenetic mechanism. They further impact on drug discovery paradigms, where modulation of activity may have therapeutic value.
Publication
Journal: Pediatric Endocrinology Reviews
November/12/2008
Abstract
OBJECTIVE
There is a strong evidence for association between type 1 diabetes and Celiac Disease. Up to 8% of patients with type1 diabetes have characteristic features of CD on small intestinal biopsy. Type 1 diabetics who have HLA DQ2 or DQ8 are at risk for CD. However most of this data is from studies conducted in Europe, with mostly Caucasian population. This study aims to identify the prevalence of celiac disease in African American children with Type1 diabetes in inner city Brooklyn, New York.
METHODS
IgA and IgG Antigliadin antibodies, IgA tissue transglutaminase and HLA typing was measured in blood collected from 34 children with type1 diabetes mellitus. Patients with positive anti tissue transglutaminase antibody underwent small intestinal biopsy.
RESULTS
17 patients had elevated IgG AGA, none showed elevated IgA AGA. Only one patient had elevated IgA and anti tTG levels, and a normal small intestinal biopsy. 28 patients had HLA DQ2 or DQ8 present.
CONCLUSIONS
94% of the African American children with type1 diabetes were serology negative for celiac disease inspite of having the predisposing HLA haplotype. Only one patient was positive for anti tTG antibody, with a negative small intestinal biopsy, the prevalence of celiac disease in this population may not be similar to the other populations. Pediatric Endocrinology in review 990,2008.
Publication
Journal: European Journal of Gastroenterology and Hepatology
December/9/2003
Abstract
OBJECTIVE
It has been reported that occult gastrointestinal bleeding as detected by faecal occult blood (FOB) testing can occur in coeliac disease. This study examines whether a positive FOB is a feature of coeliac disease and whether FOB-positive subjects need investigation for coeliac disease.
METHODS
First, the records of patients on the Nottingham Register for Coeliac Disease were reviewed for positive FOB testing. Second, the Nottingham colorectal cancer screening trial database was also reviewed to examine how many coeliac patients on the Register had participated and to examine their FOB results. Finally, sera from 309 screening trial participants who were FOB-positive but had no colonic abnormality were screened for immunoglobulin A (IgA) gliadin and IgA endomysial and human tissue transglutaminase (tTG) IgA antibodies.
RESULTS
Five of 590 patients on the Register had had FOB tests at the time of diagnosis; four had positive tests during investigation of diarrhoea and/or anaemia. Of 21 patients on the Register who had participated in the colorectal cancer screening trial, one had a positive FOB test and was found to have a rectal tubulo-villous adenoma. Of the 309 FOB-positive patients, 7% (22 subjects) were positive for IgA gliadin antibodies, but none had IgA endomysial antibodies detected and two subjects had positive human tTG antibody assays for coeliac disease.
CONCLUSIONS
Occult gastrointestinal bleeding occurs in a small number of symptomatic coeliac disease patients before diagnosis, but is no more frequent in treated and undetected coeliac disease patients than in the general population. Unless there are other indications, coeliac disease does not need to be considered in the investigation of a positive FOB test.
Publication
Journal: Medical Hypotheses
October/26/2005
Abstract
Chronic unexplained hypertransaminasemia is an isolated clinical manifestation of celiac disease (CD) and lacks of a clear physiopathological explanation. Since CD and tropical sprue (TS) have similar intestinal functional and histological pattern of injury and that an increased inflammatory response has been reported to occur in patients with irritable bowel syndrome (IBS), liver involvement might be expected to occur either in TS or IBS. However, according to author's prior observations, the frequency of hypertransaminasemia is significantly higher in CD than in TS and IBS-diarrhea predominant patients (IBS-D). Thus, based on current knowledge, intestinal mucosal damage, increased intestinal permeability and/or an active intestinal inflammatory response do not completely explain liver damage in CD. We hypothesize that other factors, unique to CD not present in TS or IBS-D, like gluten toxicity and the presence of tissular transglutaminase (tTG) an auto-antigen with pro-inflammatory and remodeling properties, act in addition to intestinal mucosal injury and account to hypertransaminasemia in CD. Further research focusing on the mechanisms of gluten and tTG hepatic toxicity, and/or the characterization of the expression, secretion and enteral-hepatic transport of certain pro-inflammatory cytokines is needed, to understand the possible links between intestinal and liver disorders seen in CD.
Publication
Journal: Arquivos de Gastroenterologia
October/4/2011
Abstract
BACKGROUND
Several studies have demonstrated a higher prevalence of celiac disease (CD) among females with Turner syndrome when compared to the general population. Nevertheless, there is no record in literature concerning this investigation among Brazilian patients.
OBJECTIVE
To assess the prevalence of CD among a group of Brazilian patients with Turner syndrome.
METHODS
Fifty-six females with Turner syndrome and on gluten-containing diet were screened for CD utilizing immunoglobulin A antiendomysium (IgA-EMA) and immunoglobulin A anti-tissue transglutaminase (IgA-tTG) antibody assays. Additionally, they were genotyped for CD human leukocyte antigen (CD-HLA) predisposing alleles. Patients showing positivity in serological testing were offered to perform small intestine biopsy for histological confirmation.
RESULTS
Mean age at diagnosis of Turner syndrome was 5.5 ± 4.4 years; mean age at screening for CD was 17.0 ± 9.3 years (from 10 months of age to 52 years). Two girls were positive for IgA-EMA and IgA-tTG, presented predisposing HLA-DQ2 alleles and both had the diagnosis of CD confirmed by jejunal biopsy.
CONCLUSIONS
The 3.6% prevalence of biopsy-proven CD among this group of females with Turner syndrome is 10 times higher than the one among females from the general population of the same geographical area. This result provides additional support to an association between these two disorders and restates that girls and women with Turner syndrome represent a high risk population for developing CD.
Publication
Journal: Digestive Diseases and Sciences
May/10/2005
Abstract
In recent years, there has been a marked increase in the diagnostic workups for celiac disease among military personnel, thereby significantly increasing overall laboratory testing expenditures and burden. We evaluated the serologic testing procedure in symptomatic young adults, using a "cost-effect" approach. We evaluated the serologic screening policy for celiac disease among serologically tested military personnel. The study population was divided into subgroups according to the clinical presentation prior to screening: isolated (low-risk) and combined complaints (high-risk). Sensitivity, specificity, and predictive values of serologic markers for celiac disease were evaluated. Cost analyses were based on diagnostic expenditures. Cost-effect ratio is expressed as cost per newly diagnosed patients, and cost minimization as cost per screened individuals. Five hundred thirty-eight military personnel were serologically tested for celiac disease. Eight new cases of celiac were diagnosed, all of whom belonged to the high-risk subgroup and tested positive for at least two positive serologic tests (tTG + EMA or tTG + AGA IgG + EMA). EMA Ab measured the highest sensitivity, specificity, and predictive values. Average screening expenditure was U.S. $287 per patient. The lowest cost-effect and cost minimization ratios were achieved by implementing a two-step single-marker screening protocol for high-risk subjects and one-step follow-up for low-risk subjects. Among patient population of young adults, selective diagnostic workup could result in cost-minimization without risking quality of diagnosis. From a cost-effect perspective, implemented screening procedures need to be dependent on subgroup: low-risk, clinical follow-up; and high-risk, serological testing for EMA and, only if positive, possibly a small-bowel biopsy.
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