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Publication
Journal: Scandinavian Journal of Gastroenterology
January/9/2003
Abstract
BACKGROUND
The main autoantigen recognized by the sera of patients with coeliac disease (CD) is tissue transglutaminase (tTG). A human-recombinant form of tTG was used to develop an ELISA to measure anti-tTG serum antibodies for the diagnosis of CD. Preliminary retrospective reports suggest that the human tTG-based ELISA could identify coeliac patients missed by the IgA-anti-endomysium antibody test (AEA). Whether the human recombinant tTG ELISA is sufficiently accurate to become the main diagnostic CD tool in everyday clinical practice is unknown. The objective was to determine, in a prospective study, the sensitivity and specificity of an ELISA test based on the use of human tTG compared with AEA, to analyse the discordant cases for HLA DQ2-8 and for clinical and intestinal biopsy characteristics.
METHODS
1106 patients referred to a gastrointestinal outpatient clinic for symptoms attributable to CD, 52 first-degree relatives of CD patients and 200 healthy controls were tested for both anti-human tTG and AEA antibodies.
RESULTS
Out of 1158 subjects, 146 were tested positive for anti-tTG antibodies and 140 were biopsy-proven coeliacs. The AEA test identified 126/1158 coeliacs who also tested positive for anti-tTG antibodies. The 14 patients missed by the AEA test carried the typical HLA-DQ for CD; they had normal levels of total serum IgA and had milder pathology than those with both anti-tTG and AEA positivity (P < 0001).
CONCLUSIONS
These results prove that human tTG-based ELISA is an excellent diagnostic tool for CD, for mass screening by both the specialist and the general clinic.
Publication
Journal: Cell Death and Differentiation
March/16/2005
Abstract
Although tissue transglutaminase (tTG) has been recognized as a mediator of apoptosis in various experimental models, little is currently known about the molecular mechanisms by which this protein modulates cell death. Recent work from our laboratory has shown that activation of tTG in cells exposed to the apoptotic inducer calphostin C triggers the crosslinking of dual leucine zipper-bearing kinase (DLK), a proapoptotic kinase acting as an essential component of the c-Jun amino-terminal kinase (JNK) signaling pathway. As a consequence of this observation, we have undertaken experiments to investigate the functional relevance of DLK oligomerization in tTG-mediated apoptosis. Our results indicate that, in cells undergoing calphostin C-induced apoptosis, tTG-dependent DLK oligomerization occurs early in the apoptotic response. Both immunocomplex kinase assays and immunoblotting with phosphospecific antibodies revealed that oligomer formation by tTG-mediated crosslinking reactions significantly enhanced the kinase activity of DLK and its ability to activate the JNK pathway. Moreover, functional studies demonstrate that tTG-mediated oligomerization of wild-type DLK sensitizes cells to calphostin C-induced apoptosis, while crosslinking of a kinase-inactive variant of DLK does not. Collectively, these data strongly suggest that tTG facilitates apoptosis, at least partly, by oligomerization and activation of the proapoptotic kinase DLK.
Publication
Journal: Antimicrobial Agents and Chemotherapy
January/12/2004
Abstract
The resistance to ampicillin and nalidixic acid in Shigella sonnei isolates obtained in Korea during the period 1998 to 2000 was characterized. Recently (J. Y. Oh, H. S. Yu, S. K. Kim, S. Y. Seol, D. T. Cho, and J. C. Lee, J. Clin. Microbiol. 41:421-423, 2003) ampicillin and nalidixic acid resistance was found in 49 and 70%, respectively, of the 67 S. sonnei isolates obtained during this period. We analyzed 138 S. sonnei isolates collected during the same period. Ampicillin and nalidixic acid resistance was found in 30 and 86% of the isolates, respectively. The ampicillin resistance was mediated by a TEM-1 beta-lactamase, and TEM-52 extended-spectrum beta-lactamase was identified in one sporadic S. sonnei isolate from 1999. bla(TEM-1) and bla(TEM-52) were located in conjugative R-plasmids. Tn3 was detected in 41% of the ampicillin-resistant isolates. The R-plasmids from the transconjugants that transferred resistance to ampicillin exhibited different restriction fragment length polymorphism patterns, and a bla(TEM-1) probe was hybridized with the different fragments. The nalidixic acid resistance was exclusively associated with an amino acid substitution, Ser83->>Leu (TCG->>TTG), in gyrA. These findings indicate that the genetically related S. sonnei strains readily acquire resistance to ampicillin, streptomycin, trimethoprim, and sulfamethoxazole but not nalidixic acid through conjugative R-plasmids from difference sources when confronted by antibiotic selective pressures.
Publication
Journal: International Archives of Allergy and Immunology
January/9/2012
Abstract
BACKGROUND
The role of regulatory T cells expressing FOXP3 in the pathogenesis of coeliac disease (CD) and type 1 diabetes (T1D) has been reported. Recent data have placed special focus on the interplay between the intestinal barrier and immunoregulatory processes. We aimed to determine whether the expression of tight junction protein 1 (TJP1), which reflects small bowel mucosa permeability, is changed in CD and T1D.
METHODS
Transcription levels of TJP1 and FOXP3 genes were evaluated in the small bowel biopsies of 14 children with CD, 12 with CD and coexisting T1D and 40 controls using real-time PCR. Serum IgA and IgG to deamidated gliadin, bovine β-lactoglobulin, bovine α-casein and human tissue transglutaminase (tTG) were determined by ELISA.
RESULTS
The highest expression of FOXP3 mRNA was seen in patients with CD and T1D compared to patients with CD alone and controls (p = 0.02). In contrast, the lowest level of TJP1 mRNA expression was found in patients with CD and T1D (p = 0.01). The levels of IgA to deamidated gliadin and tTG were highest in patients with CD and T1D (p = 0.0001 and 0.01, respectively). The expression of FOXP3 mRNA correlated highly with the level of anti-gliadin IgA (p = 0.02) and anti-tTG IgA antibodies (p = 0.004).
CONCLUSIONS
The significant decline in TJP1 expression in CD patients, particularly in those with coexisting T1D, was accompanied by an increase in FOXP3 expression. This might reflect an attempt to maintain immune tolerance to counterbalance the loss of mucosal integrity in the small intestine in CD associated with T1D.
Publication
Journal: Indian Journal of Gastroenterology
December/4/2006
Abstract
BACKGROUND
We prospectively evaluated the usefulness of IgA tissue transglutaminase antibodies (IgA tTG) in the initial diagnosis of celiac disease (CD) and compared its diagnostic potential with that of IgA anti-endomysial antibodies (IgA EMA) and anti-IgA and IgG gliadin antibodies (AGA and AGG, respectively).
METHODS
Sera of 23 untreated children fulfilling the revised ESPGHAN criteria for diagnosis of CD (Group I; mean age 10.8 y); 19 disease controls (Group II; mean age 8.5 y) presenting with chronic diarrhea, short stature or both; and 22 healthy children (Group III; mean age 8.8 y) were studied. These were tested in a blinded manner for AGA, AGG, IgA tTG (guinea pig as antigen) and IgA EMA.
RESULTS
In Group I, IgA EMA was positive in 19, IgA tTG in 17, AGA in 14 and AGG in 17 patients. In Group II, these tests were positive in 1, 0, 2 and 14 patients, respectively and in Group III, in 0, 0, 0 and 1 child, respectively. Analyzing data from Group I and II, IgA EMA, IgA tTG, AGA and AGG had sensitivity rates of 83%, 74%, 61% and 74%, respectively; the specificity rates were 95%, 100%, 89% and 26%; positive predictive values were 95%, 100%, 88% and 55% and negative predictive values were 82%, 74%, 65% and 45%, respectively.
CONCLUSIONS
IgA tTG is useful for the diagnosis of CD, with sensitivity and specificity rates comparable to those of EMA and this test is well suited for use in tropical countries like India.
Publication
Journal: Bone
September/25/2008
Abstract
A reduced bone mineral density has been reported in patients with untreated celiac disease (CD) as well as in patients with poorly controlled type 1 diabetes mellitus (T1DM). The aim of this study was to evaluate the bone mineral status by phalangeal quantitative ultrasound in 52 children and adolescents with both diseases (mean age 13.3+/-4.9 years). As a control group 50 patients with T1DM and no CD (age 12.2+/-4.0 years) were studied. The following bone parameters, amplitude-dependent speed of sound (AD-SoS) and bone transmission time (BTT) were considered and expressed as z score. Compliance to gluten free diet and long term glycemic control (mean of four determinations of HbA1c in the last year) were also assessed. The lowest mean AD-SoS z score values were found in patients with T1DM and CD, who reported transgressions to gluten free diet and exhibited positivity for serum anti-tissue transglutaminase antibodies (tTG) and/or endomysial antibodies (EmA), compared with patients with occasional transgressions but negative for anti-tTG and/or -EmA, patients strictly adherent to the diet, and patients who suffered only from diabetes (ANOVA p=0.021). No difference was found between patients with diabetes alone and patients with both diseases strictly adherent to gluten free diet. Prevalence of osteopenia (z AD-SoS values <-2 SD) was higher in patients with T1DM and CD and poor compliance to the diet (45.5%) compared with patients with T1DM (8%) or patients with both diseases strictly compliant to diet (12.9%) (p=0.015). A negative correlation between Ad-SoS z score and HbA1c (r -0.236, p=0.036) was found when patients with T1DM and patients with T1DM and CD, who strictly adhere to the diet, were pooled. In conclusion the quality of bone as assessed by phalangeal ultrasound in patients with T1DM and CD, who strictly adhere to gluten free diet, is similar to that found in T1DM patients. A higher prevalence of osteopenia is present in patients with both diseases who reported habitual transgressions to gluten free diet. The gluten free diet, as well as the optimization of glycemic control, plays an important role in preventing the osteopenic status caused by the clustering of these two chronic diseases.
Publication
Journal: Digestive and Liver Disease
November/26/2007
Abstract
BACKGROUND
Previous studies have demonstrated that serum anti-actin antibodies are a reliable marker of intestinal damage severity in coeliac disease.
OBJECTIVE
To validate in a multicentre study the clinical usefulness of serum IgA anti-actin antibody ELISA and its possible use in monitoring intestinal mucosa lesions during gluten-free diet.
METHODS
Four centres recruited 205 newly diagnosed coeliac disease patients with villous atrophy, 80 healthy controls and 81 "disease" controls. Twelve coeliac disease patients on gluten-free diet but with persistent symptoms underwent serum IgA anti-actin antibody assay and intestinal histology evaluation. IgA anti-actin antibody ELISA was performed with a commercial kit. All coeliac disease patients underwent intestinal histology study.
RESULTS
IgA anti-actin antibodies showed a sensitivity of 80% and a specificity of 85% in the diagnosis of coeliac disease patients with villous atrophy. The area under the receiving operator curve for anti-actin antibodies was 0.873 [95% C.I. 0.805-0.899]. Serum anti-actin antibodies values were significantly higher in coeliac disease patients than in healthy or "disease" controls (P<0.0001). Serum anti-actin antibodies were positive in 41 of the 60 coeliac disease patients with mild intestinal histology lesions (69%) and in 123 of the 145 with severe lesions (85.3%) (P<0.05). There was a significant inverse correlation between anti-actin antibody values and the villi/crypts ratio (r=-0.423; P<0.0001). In the 12 coeliac disease patients on gluten-free diet who underwent re-evaluation as they were persistently symptomatic, intestinal histology showed three cases with persistent villous atrophy: all of these were positive for serum anti-actin antibodies ELISA, whereas both serum anti-tTG and EmAs were negative. The other nine patients showed normal intestinal villi and were negative for serum anti-actin antibodies.
CONCLUSIONS
Anti-actin antibodies are a reliable marker of severe intestinal mucosa damage in coeliac disease patients and a simple ELISA technique offers an accurate method for their determination. These antibodies seem to be a very reliable marker of persistent intestinal damage in coeliac disease patients.
Publication
Journal: Translational research : the journal of laboratory and clinical medicine
April/18/2013
Abstract
The existence of mild forms of celiac disease (CD) can make the histology-based diagnosis difficult to reach. Since anti-endomysium (EMA) and anti-tissue transglutaminase (anti-tTG) are detectable in culture supernatants of duodenal biopsies from CD patients, our aim was to assess if this system can support the histology in the diagnostic work-up. A total of 559 suspected CD patients underwent serum EMA/anti-tTG detection, upper endoscopy with duodenal biopsy sampling, histologic analysis, and organ culture to detect EMA/anti-tTG in supernatants. A subgroup of 30 patients with organ culture positive results were put on a gluten-free diet (GFD). Their gluten-dependency was evaluated by the psychological general well-being and beck depression inventory indexes. Statistical analysis was performed by Cohen k inter-test, Friedman test, and Dunn multiple comparison. Two hundred forty-one out of 559 (43.1%) patients showed intestinal villous atrophy, whereas serum and organ culture EMA/anti-tTG were positive in 293/559 (52.4%) and 334/559 (59.7%) patients, respectively. The strength of agreement resulted good for serology vs histology (k = 0.730), good for organ culture vs histology (k = 0.662), and very good for serology vs organ culture (k = 0.852). After 12 months of GFD, psychological general well-being index significantly increased, and beck depression inventory index significantly decreased (P < 0.001 for each one). Data highlight the organ culture system as a useful tool to assist the histology in diagnosing CD, mainly in cases without villous atrophy or in seronegative patients. The marked improvement in quality of life after a GFD further supports the reliability of this system in diagnosing CD.
Publication
Journal: Clinical and Experimental Immunology
April/1/2009
Abstract
Refractory coeliac disease (RCD) is a very rare and dangerous form of CD, in which gluten-free diet loses its therapeutic effect and the damage of intestinal mucosa persists. Because of the adherence to the diet, serological markers of CD [immunoglobulin A (IgA) antibodies against gliadin, tissue transglutaminase (tTG) and endomysium] are often missing in RCD patients. We found substantially elevated levels of IgA anti-calreticulin (CRT) antibodies in the sera of almost all RCD patients tested. These sera were negative for IgA antibodies to gliadin and tTG and only some of them showed IgA antibodies to enterocytes. Analysis of patients' IgA reactivity to CRT fragments (quarters and halves) by Western blotting revealed differences in the specificity of IgA antibodies between RCD and CD patients. We therefore used the Pepscan technique with synthetic overlapping decapeptides of CRT to characterize antigenic epitopes recognized by serum IgA antibodies of RCD patients. Employing this method we demonstrated several dominant antigenic epitopes recognized by IgA antibodies of RCD patients on the CRT molecule. Epitope GVTKAAEKQMKD was recognized predominantly by serum IgA of RCD patients. Our results suggest that testing for serum IgA antibodies against CRT and its selected peptide could be a very useful tool in RCD differential diagnosis.
Publication
Journal: Archives of Medical Science
January/15/2013
Abstract
BACKGROUND
To explore the effect of tumor suppressor in lung cancer 1 (TSLC1) on proliferation and apoptosis in esophageal cancer Eca109 cells.
METHODS
Eca109 cells were divided into three groups: TSLC1 transfected group (TTG), mock group (MG) and untransfected group (UTG). The TTG and MG were transfected transiently with the pIRES2-EGFP-TSLC1 eukaryotic expression vector and pIRES2-EGFP vector respectively. The UTG was a blank control. The TSLC1 expression in TTG was analyzed with the fluorogram and RT-PCR method. Cell proliferation was measured with 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium (MTT) assay. Cell cycle was measured by flow cytometry (FCM). Cell apoptosis was detected by Annexin-V/PI double staining FCM.
RESULTS
Green color was found in TTG and MG. The band of TSLC1 mRNA of TTG was located at about 1400 bp by RT-PCR and agarose gel electrophoresis assay. The TSLC1 inhibited cell proliferation significantly in MTT assay, and the cell proliferation was slower in TTG than MG and UTG. After TSLC1 transfection, cell numbers increased in G0/G1 phase and decreased in S phase. Forty-eight hours after transfection, the apoptosis rate and death rate of TTG were higher than MG and UTG. Thus TSLC1 induced Eca109 cells to apoptosis.
CONCLUSIONS
The TSLC1 gene had a potent effect on cell proliferation inhibition, G1/S cell cycle arrest and induction of cell apoptosis in Eca109 cells.
Publication
Journal: Przeglad Lekarski
September/14/2009
Abstract
Celiac disease is increasingly recognized autoimmune enteropathy caused by a permanent gluten intolerance. Gluten is the main storage protein of wheat, in genetically predisposed individuals. Celiac disease risk in first degree relatives is about 10%. Diarrhea and changes of bowel movement, observed as well in celiac disease as in IBS, may lead to misdiagnosis of IBS basing on the Rome criteria or may be associated with coexistence of both diseases. The aim of the study was to assess the celiac disease prevalence in patients with irritable bowel syndrome. The study group comprised 200 patients (120 women and 80 men) aged 18-78 years (mean: 46.7 years) with diarrhoeal form of irritable bowel syndrome (IBS), according to the Rome criteria II. At the beginning and after a three month period anti tissue transglutaminase antibodies (IgA tTG) were estimated. Gastroscopy with biopsy where performed in those with IgA tTG titre above 1/200. 40 patients were immunologically positive and 14 of them have histopathologically proven celiac disease. In the group of patients with detected celiac disease, gluten free diet was applied besides the treatment with trimebutin or mebewerin, recommended for IBS. After 6 months the decrease of IgA tTG titre in the serum was observed. In 5 of these patients IgA tTG level was negative. It was associated with the significant decrease of clinical symptoms, such as diarrhea and flatulence. The remaining symptoms, such as abdominal pain, feeling of incomplete defecation demanded continuation of IBS treatment. With regard to often atypical celiac disease symptoms--adult active searching should be performed to differentiate from irritable bowel syndrome.
Publication
Journal: Annals of Saudi Medicine
May/3/2011
Abstract
OBJECTIVE
Celiac disease (CD) is an immune-mediated enteropathy, induced by gluten in genetically susceptible individuals. The objective of this study was to describe the clinical pattern of CD in children from the western region of Saudi Arabia.
METHODS
Retrospective, hospital-based.
METHODS
This study included children with a biopsy-proven diagnosis of CD made between September 2002 and July 2007. Children were admitted to the endoscopy unit for a small-bowel biopsy if they had gastrointestinal symptoms suggestive of CD or if they were positive for a CD-antibody screen performed for the high-risk groups.
RESULTS
Eighty children were identified with a diagnosis of CD. Their mean (SD) age was 9.6 (4.9) years (range, 0.5-18 years). There were 44 (55%) female patients. Forty-one (51%) patients were detected during screening of high-risk groups, while 39 (49%) patients had classical symptoms of malabsorption. The screening also detected asymptomatic patients. Of 65 patients tested, 11 (17%) had elevated liver function tests, which reverted to normal after introduction of a gluten-free diet (GFD) except in one case. Seventy-three (91%) patients were positive for anti-tissue transglutaminase antibodies, 18 (23%), for IgG anti-gliadin antibodies; and 46 (58%), for IgA anti-gliadin antibodies. Forty-one (56%) patients showed good adherence to GFD as assessed by dietary history and the decline in anti-tTG level.
CONCLUSIONS
CD may present with classical symptoms or be identified through screening programs. Growth and laboratory abnormalities usually improve after introduction of a GFD. Adherence to a GFD remains a problem; therefore, thorough assessment and counseling at the time of diagnosis and ongoing care are crucial.
Publication
Journal: International Journal of Preventive Medicine
October/1/2012
Abstract
BACKGROUND
Celiac disease (CD) has been found in up to 10% of the patients presenting with unexplained abnormal liver function tests (LFT). As there is no precise data from our country in this regard, we investigated the prevalence of CD in patients presenting with abnormal LFT.
METHODS
From 2003 to 2008, we measured IgA anti-tissue transglutaminase (t-TG) antibody (with ELISA technique) within the first-level screening steps for all patients presenting with abnormal LFT to three outpatient gastroenterology clinics in Isfahan, IRAN. All subjects with an IgA anti-tTG antibody value of >10 μ/ml (seropositive) were undergone upper gastrointestinal endoscopy and duodenal biopsy. Histopathological changes were assessed according to the Marsh classification. CD was defined as being seropositive with Marsh I or above in histopathology and having a good response to gluten free diet (GFD).
RESULTS
During the study, 224 patients were evaluated, out of which, 10 patients (4.4%) were seropositive for CD. Duodenal biopsies were performed in eight patients and revealed six (2.7%) cases of Marsh I or above (four Marsh IIIA, two Marsh I), all of them had good response to GFD. The overall prevalence of CD among patients with hypertransaminasemia, autoimmune hepatitis, and cryptogenic cirrhosis was determined as 10.7% (3/28), 3.4% (2/59), and 5.3% (1/19), respectively.
CONCLUSIONS
Serological screening with IgA anti-tTG antibody test should be routinely performed in patients presenting with abnormal LFT and especially those with chronic liver diseases including hypertransaminasemia, autoimmune hepatitis, and cryptogenic cirrhosis.
Publication
Journal: Scandinavian Journal of Gastroenterology
August/16/2017
Abstract
BACKGROUND
Since the recognition of tissue transglutaminase (tTG) as the target antigen of anti-endomysium antibodies, several ELISA assays using either guinea pig or human recombinant tTG have been developed. The aim of the study was to compare the behaviour of anti-tTG and anti-endomysium antibodies assays in coeliacs and in patients with chronic liver disease.
METHODS
34 patients (24 women, 34.9 ± 12.5 years) with coeliac disease and 41 with chronic liver disease (14 women, 57 ± 11.2 years), including 19 cirrhotics, were evaluated for anti-endomysium antibodies by indirect immunofluorescence and for anti-tTG IgA antibodies by ELISA, using guinea pig liver or human recombinant transglutaminase.
RESULTS
The prevalences of anti-tTG and anti-endomysium antibodies were 100% in patients with coeliac disease at diagnosis, 75% and 64.3% in patients on a gluten-free diet. All liver disease patients were negative for anti-endomysium antibodies, while 11 (26.8%) were positive for anti-tTG. All these patients had liver cirrhosis and represented 57.9% of all cirrhotics. The presence of anti-tTG was associated with higher Child-Pugh scores. The use of human transglutaminase determined a reduction in the rate of positive results; however, the rate of positive anti-tTG was still 17.1% in all liver disease patients and 31.6% in cirrhotics.
CONCLUSIONS
Our data confirm that anti-tTG have a similar sensitivity compared with anti-endomysium antibodies assay in coeliacs. However, a high prevalence of positive anti-tTG results is observed in cirrhotic patients, even when human recombinant tTG is used. The high prevalence of positive results among cirrhotic patients is associated with more advanced liver disease.
Publication
Journal: Indian Journal of Gastroenterology
October/1/2015
Abstract
BACKGROUND
There is limited data on celiac disease in patients with cryptogenic cirrhosis or idiopathic noncirrhotic intrahepatic portal hypertension (NCIPH). Our objective was to evaluate for celiac disease in patients with portal hypertension in India.
METHODS
Consecutive patients with portal hypertension having cryptogenic chronic liver disease (cases) and hepatitis B- or C-related cirrhosis (controls) were prospectively enrolled. We studied tissue transglutaminase (tTG) antibody and duodenal histology in study patients.
RESULTS
Sixty-one cases (including 14 NCIPH patients) and 59 controls were enrolled. Celiac disease was noted in six cases (including two NCIPH patients) as compared to none in controls. In a significant proportion of the remaining study subjects, duodenal biopsy showed villous atrophy, crypt hyperplasia, and lamina propria inflammation, not accompanied by raised intraepithelial lymphocytes (IELs); this was seen more commonly in cases as compared to controls. An unexpectedly high rate of tTG antibody positivity was seen in study subjects (66 %) of cases as compared to 29 % in controls (p-value < 0.001), which could indicate false-positive test result.
CONCLUSIONS
In this study, 10 % of patients with unexplained portal hypertension (cryptogenic chronic liver disease) had associated celiac disease. In addition, an unexplained enteropathy was seen in a significant proportion of study patients, more so in patients with cryptogenic chronic liver disease. This finding warrants further investigation.
Publication
Journal: Oncotarget
September/14/2017
Abstract
Tissue transglutaminase (tTG), a dual-function enzyme with GTP-binding and acyltransferase activities, has been implicated in the survival and chemotherapy resistance of aggressive cancer cells and cancer stem cells, including glioma stem cells (GSCs). Using a model system comprising two distinct subtypes of GSCs referred to as proneural (PN) and mesenchymal (MES), we find that the phenotypically aggressive and radiation therapy-resistant MES GSCs exclusively express tTG relative to PN GSCs. As such, the self-renewal, proliferation, and survival of these cells was sensitive to treatment with tTG inhibitors, with a benefit being observed when combined with the standard of care for high grade gliomas (i.e. radiation or temozolomide). Efforts to understand the molecular drivers of tTG expression in MES GSCs revealed an unexpected link between tTG and a common marker for stem cells and cancer stem cells, Aldehyde dehydrogenase 1A3 (ALDH1A3). ALDH1A3, as well as other members of the ALDH1 subfamily, can function in cells as a retinaldehyde dehydrogenase to generate retinoic acid (RA) from retinal. We show that the enzymatic activity of ALDH1A3 and its product, RA, are necessary for the observed expression of tTG in MES GSCs. Additionally, the ectopic expression of ALDH1A3 in PN GSCs is sufficient to induce the expression of tTG in these cells, further demonstrating a causal link between ALDH1A3 and tTG. Together, these findings ascribe a novel function for ALDH1A3 in an aggressive GSC phenotype via the up-regulation of tTG, and suggest the potential for a similar role by ALDH1 family members across cancer types.
Publication
Journal: Journal of Drugs in Dermatology
August/5/2013
Abstract
BACKGROUND
Despite the escalating number of patients undergoing aesthetic BoNT-A procedures, a standardized, objective means of setting treatment goals and measuring the success of treatment is lacking. Treat-To-Goal (TTG) is a new approach to consent that utilizes the Merz Aesthetics Scale to set objectively defined start points and treatment goals to better inform the consent process and provide a means of measuring the success of treatment.
OBJECTIVE
To evaluate the TTG approach vs standard consent procedures in terms of patient understanding of the risks and benefits of treatment.
METHODS
This study was undertaken in 2 phases among consecutive patients presenting for BoNT-A treatment. Phase 1 consisted of a crossover comparison of patient satisfaction with standard consent vs the TTG approach (n=20). Patient understanding of the likely outcomes and risks associated with treatment following consent and their overall preference were assessed using 10-point visual analog scales (VAS). Phase 2 assigned patients to receive no treatment (n=10) or treatment with BoNT-A (n=54) following consent with the TTG approach. Patients were followed up with 28 days later to assess whether the goals defined during consent had been met.
RESULTS
The TTG approach significantly improved patient understanding of likely outcomes of BoNT-A treatment compared with standard consent (P=.004 when standard consent assessed first, and P=.002 when TTG assessed first). All patients assessed preferred the TTG approach (median VAS score in favor of TTG: 7.0, P<.0001). Target improvements were successfully met or exceeded in at least one treatment area (forehead, glabellar lines, crow's feet) in all patients treated with BoNT-A. In contrast, none of the untreated patients met their target improvements unless the target was defined as no change.
CONCLUSIONS
The TTG approach represents a significant improvement over standard consent in terms of the information it provides to patients. Further investigation of this concept is warranted.
Publication
Journal: Journal of Integrative Plant Biology
July/25/2016
Abstract
Ethylene responsive factors (ERFs) are plant-specific transcription factors that are involved in a variety of biological processes. We previously demonstrated that an ERF gene from Tamarix hispida, ThERF1, encodes a protein binding to GCC-box and DRE motifs and negatively modulates abiotic stress tolerance. In the present study, microarray analysis was performed to study the genes regulated by ThERF1 on a genomic scale. There were 154 and 307 genes (respectively representing 134 and 260 unique genes) significantly up- and downregulated by ThERF1 under salt stress conditions, respectively. A novel motif, named TTG, was identified to be recognized by ThERF1, which commonly presents in the promoters of ThERF1-targeted genes. The TTG motif is also bound by other ERFs of a different subfamily from T. hispida and Arabidopsis, indicating that it is commonly recognized by ERF proteins. The binding affinities of ERFs to the TTG motif are significantly induced by salt stress. The TTG motif is more enriched than the GCC-box and DRE motifs in the promoters of ThERF1-targeted genes. Taken together, these studies suggested that the TTG motif plays an important role in the gene expression regulated by ERFs in response to salt stress.
Publication
Journal: FEBS Letters
April/17/1997
Abstract
A significant increase in the expression and activity of tissue transglutaminase (tTG), one of the effector elements of apoptosis, was observed during involution of thymus elicited by treatment with either anti-CD3 antibody or dexamethasone or by irradiation. The blood plasma concentration of epsilon(gamma-glutamyl)lysine isodipeptide, the end-product of the digestion of transglutaminase cross-linked proteins, was also elevated in each of these cases. tTG was localized in cells of the cortical layer of the thymus and immunofluorescence double staining revealed that the enzyme appeared in the apoptotic cells. None of these observations could be made when apoptosis was induced by fas-receptor stimulation. The lack of tTG activity in fas-stimulated cells was accompanied with a less organized apoptotic morphology. Our data suggest that distinct signalling pathways, which induce apoptosis within the same cell type, can differentially regulate the expression of tTG, and this enzyme may be involved in structural stabilization of the apoptotic cells.
Publication
Journal: American Journal of Respiratory Cell and Molecular Biology
October/16/1997
Abstract
At birth, the mammalian lung is still immature. The alveoli are not yet formed and the interairspace walls contain two capillary layers which are separated by an interstitial core. After alveolarization (first 2 postnatal weeks in rats) the alveolar septa mature: their capillary layers merge, the amount of connective tissue decreases, and the mature lung parenchyma is formed (second and third week). During the first 3 wk of life the role of tissue transglutaminase (tTG) was studied in rat lung by immunostaining of cryostat and paraffin sections, by Northern and Western blotting, and by a quantitative determination of gamma-glutamyl-epsilon-lysine. While enzyme activity and intracellular tTG were already present before term, the enzyme product (gamma-glutamyl-epsilon-lysine-crosslink) and extracellular tTG appeared between postnatal days 10 and 19 in the lung parenchyma. In large blood vessels and large airways, which mature earlier than the parenchyma, both the enzyme product and extracellular tTG had already appeared at the end of the first postnatal week. We conclude that tTG is expressed and externalized into the extracellular matrix of lung shortly before maturation of an organ area. Because tTG covalently and irreversibly crosslinks extracellular matrix proteins, we hypothesize that it may prevent or delay further remodeling of basement membranes and may stabilize other extracellular components, such as microfibrils.
Publication
Journal: International Journal of Colorectal Disease
December/1/2004
Abstract
OBJECTIVE
Inflammatory bowel diseases (IBD) evoke a damage-repair process accompanied by the activation of apoptotic genes. Data on transglutaminase (TG) expression in apoptotic cells in inflamed colonic epithelium has not been reported, although TG cross-links proteins within typical apoptotic bodies in various cell lines. In an experimental model of colitis we investigated the expression of different markers of apoptosis related to the degree and development of colonic inflammation.
METHODS
Two studies were performed: (a) Colitis was induced by the administration of 2,4,6-trinitrobenzen sulfonic acid (TNBS) at a dose of 10 or 20 mg per rat in 50% ethanol, and the rats were killed 1 week later; (b) Colitis was induced by 20 mg TNBS and the rats were killed 3 days, 1, 2, and 4 weeks thereafter. The colon of rats was macroscopically assessed, and biopsies were histologically assessed and immunoprobed for FasL, FasR, p53 and tTG. Cell death was detected by TUNEL, and TG activity was assayed on colon homogenates.
RESULTS
Study A: According to enhanced TUNEL positivity, FasR/FasL and p53 expression increased depending on the severity of the colitis. Study B showed increased p53 expression at day 3 while FasR/FasL coexpression peaked at 1 week. In both studies tTG was mainly expressed in the extracellular matrix of damaged tissue and in the submucosa.
CONCLUSIONS
Our findings suggest that expression of apoptosis markers is related to the degree of colitis and show that apoptosis is sustained by both p53 and FasR/FasL pathways, depending on the phase of colitis development. Moreover, the lack of TG staining in typical apoptotic bodies may account for a perturbation of the cross-linked apoptotic envelope that may be an important determinant in the development of immune response in ulcerative colitis.
Publication
Journal: Journal of Alzheimer's Disease
June/9/2008
Abstract
BACKGROUND
Protein cross-linking and aggregation are important molecular processes in Alzheimer's disease (AD), and tissue transglutaminase (tTG) catalyzes protein cross-linking.
OBJECTIVE
To measure tTG, tTG enzyme activity and isopeptide, which is the product of tTG, in brain and to relate them to cognitive scores.
METHODS
tTG and isopeptide levels were measured in frontal gray matter of 10 normal (NCI), 10 mild cognitive impairment (MCI) and 9 AD brains from the Religious Orders Study. tTG enzymatic activity was measured with a fluorescence assay.
RESULTS
tTG protein and enzyme activity were highest in AD, but not significantly greater than MCI or NCI. In contrast, isopeptide immunoreactivity in formic acid extracts was significantly greater in AD than NCI and MCI. The level of insoluble formic acid extractable isopeptide correlated with several measures of cognitive function, including word generation and perceptual speed. Multiple linear regression analyses indicated that insoluble isopeptide immunoreactivity could be accounted for by a combination of factors in the formic acid extract, including Abeta, ubiquitin and tau.
CONCLUSIONS
Accumulation of insoluble proteins with isopeptide bonds correlates with cognitive impairment. The relationship of isopeptide to other proteins that are also enriched in formic acid extracts suggests that several substrates of tTG may play a role in the pathogenesis of AD.
Publication
Journal: Journal of Pediatric Gastroenterology and Nutrition
April/30/2007
Abstract
BACKGROUND
Celiac disease (CD) is overrepresented among patients with Down syndrome (DS), who frequently lack any typical symptoms. Therefore, screening for CD is recommended in this high-risk group. The aim of the study was to determine the prevalence of CD in Arab children with DS and evaluate the contribution of immunoglobulin (Ig) A and IgG anti-gliadin antibodies (AGA), IgA and IgG tissue transglutaminase (TTG) antibodies, and IgA anti-endomysial antibodies (EMA) to screen for CD in children with DS.
METHODS
A total of 52 Arab patients with DS and 52 healthy Arab control subjects were studied for CD using various serological markers. Data on age, sex, weight, height, gastrointestinal symptoms, and endocrine abnormalities were recorded. Human leukocyte antigen (HLA) was studied in patients undergoing small intestinal biopsy.
RESULTS
Five patients with DS were IgA TTG-positive and only 1 patient with DS was IgG TTG-positive. EMA was negative in all patients with DS. TTG (IgA and IgG) and EMA were negative in all control children. IgA AGA was positive in 12 patients with DS and 3 control subjects (P = 0.02), whereas IgG AGA was positive in 41 patients with DS and 26 control subjects (P = 0.004). Only children testing positive for TTG underwent upper endoscopy with duodenal biopsy. Two children with DS were diagnosed with CD. Both patients were IgA TTG-positive. One was HLA DQ2-positive and another was negative for HLA DQ2 and DQ8.
CONCLUSIONS
CD is prevalent (3.8%) in Arab patients with DS. Based on our cohort, IgA TTG is useful in diagnosing patients with CD and DS.
Publication
Journal: Clinical Gastroenterology and Hepatology
March/10/2016
Abstract
OBJECTIVE
Celiac disease is underdiagnosed. Many patients are examined by endoscopy, but celiac disease is missed or not detected. We evaluated the accuracy of finger prick-based point-of-care tests in the detection of celiac disease and developed an algorithm for diagnosis.
METHODS
We performed a prospective study of 2 groups of patients with celiac disease evaluated at the Royal Hallamshire Hospital in Sheffield (United Kingdom) from March 2013 through February 2014. In group 1, patients at high risk of celiac disease who tested positive for endomysial antibody (n = 55) were evaluated using the Biocard test (BHR Pharmaceuticals, Nuneaton, UK) and the Celiac Quick Test (Biohit Healthcare UK, Ellesmere Port, UK), which measure antibodies to tissue transglutaminase (anti-tTG), and the Simtomax test (Tillotts Pharma, Rheinfelden, Switzerland), which measures deamidated gliadin peptide antibodies (DGP). Patients in group 2 (508 consecutive patients who underwent an endoscopy examination for any indication) received the DGP test, and also were evaluated using a diagnostic algorithm that incorporated results from the DGP test and data on symptoms. In both groups, point-of-care tests were taken at the time of endoscopy and results were compared with results from histologic analyses of duodenal biopsy specimens from all patients.
RESULTS
In group 1, the DGP test identified patients with celiac disease with 94.4% sensitivity, the Celiac Quick Test identified patients with 77.8% sensitivity (P = .03 vs the DGP test), and the Biocard test identified patients with 72.2% sensitivity (P = .008 vs the DGP test). In group 2, the DGP test identified patients with celiac disease with 92.7% sensitivity (95% confidence interval, 83.0-97.3), 85.2% specificity (95% confidence interval, 81.5-88.3), a positive predictive value of 49.2% (95% confidence interval, 40.3-58.2), and a negative predictive value of 98.7% (95% confidence interval, 96.8-99.5). Measurement of serum anti-tTG identified patients with celiac disease with 91.2% sensitivity (95% confidence interval, 81.1-96.4), 87.5% specificity (95% confidence interval, 84.0-90.4), a positive predictive value of 53.0% (95% confidence interval, 43.6-62.2), and a negative predictive value of 98.5% (95% confidence interval, 96.5-99.4). The algorithm identified patients with celiac disease with 98.5% sensitivity; its use could reduce duodenal biopsies by 35%.
CONCLUSIONS
In a prospective study, a test for DGP identified patients with celiac disease with similar levels of sensitivity and specificity as standard serologic analysis of anti-tTG. Use of the DGP test before endoscopy could increase the accuracy of the diagnosis of celiac disease. Further studies, in lower-prevalence populations, are required to assess the impact of the test in clinical practice.
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