Functional activation of pyruvate dehydrogenase in human brain using hyperpolarized [1-13 C]pyruvate.

PURPOSE: Pyruvate, produced from either glucose, glycogen, or lactate, is the dominant precursor of cerebral oxidative metabolism. Pyruvate dehydrogenase (PDH) flux is a direct measure of cerebral mitochondrial function and metabolism. Detection of [13 C]bicarbonate in the brain from hyperpolarized [1-13 C]pyruvate using carbon-13 (13 C) MRI provides a unique opportunity for assessing PDH flux in vivo. This study is to assess changes in cerebral PDH flux in response to visual stimuli using in vivo 13 C MRS with hyperpolarized [1-13 C]pyruvate. METHODS: From seven sedentary adults in good general health, time-resolved [13 C]bicarbonate production was measured in the brain using 90° flip angles with minimal perturbation of its precursors, [1-13 C]pyruvate and [1-13 C]lactate, to test the hypothesis that the appearance of [13 C]bicarbonate signals in the brain reflects the metabolic changes associated with neuronal activation. With a separate group of healthy participants (n = 3), the likelihood of the bolus-injected [1-13 C]pyruvate being converted to [1-13 C]lactate prior to decarboxylation was investigated by measuring [13 C]bicarbonate production with and without [1-13 C]lactate saturation. RESULTS: In the course of visual stimulation, the measured [13 C]bicarbonate signal normalized to the total 13 C signal in the visual cortex increased by 17.1% ± 15.9% (p = 0.017), whereas no significant change was detected in [1-13 C]lactate. Proton BOLD fMRI confirmed the regional activation in the visual cortex with the stimuli. Lactate saturation decreased bicarbonate-to-pyruvate ratio by 44.4% ± 9.3% (p < 0.01). CONCLUSION: We demonstrated the utility of 13 C MRS with hyperpolarized [1-13 C]pyruvate for assessing the activation of cerebral PDH flux via the detection of [13 C]bicarbonate production.

Dual-phase imaging of cardiac metabolism using hyperpolarized pyruvate.

PURPOSE: Previous cardiac imaging studies using hyperpolarized (HP) [1-13 C]pyruvate were acquired at end-diastole (ED). Little is known about the interaction between cardiac cycle and metabolite content in the myocardium. In this study, we compared images of HP pyruvate and products at end-systole (ES) and ED. METHODS: A dual-phase 13 C MRI sequence was implemented to acquire two sequential HP images within a single cardiac cycle at ES and ED during successive R-R intervals in an interleaved manner. Each healthy volunteer (N = 3) received two injections of HP [1-13 C]pyruvate for the dual-phase imaging on the short-axis and the vertical long-axis planes. Spatial distribution of HP 13 C metabolites at each cardiac phase was correlated to multiphase 1 H MRI to confirm the mechanical changes. Ratios of myocardial HP metabolites were compared between ES and ED. Segmental analysis was performed on the midcavity short-axis plane. RESULTS: In addition to mechanical changes, metabolic profiles of the heart detected by HP [1-13 C]pyruvate differed between ES and ED. The myocardial signal of [13 C]bicarbonate relative to [1-13 C]lactate was significantly smaller at ED than the ratio at ES (p < .05), particularly in mid-anterior and mid-inferoseptal segments. The distinct metabolic profiles in the myocardium likely reflect the technical aspects of the imaging approach such as the coronary flow in addition to the cyclical changes in metabolism. CONCLUSION: The study demonstrates that metabolic profiles of the heart, measured by HP [1-13 C]pyruvate, are affected by the cardiac cycle in which that the data are acquired.

Characterization and compensation of f0 inhomogeneity artifact in spiral hyperpolarized 13 C imaging of the human heart.

PURPOSE: This study aimed to investigate the role of regional f0 inhomogeneity in spiral hyperpolarized 13 C image quality and to develop measures to alleviate these effects. METHODS: Field map correction of hyperpolarized 13 C cardiac imaging using spiral readouts was evaluated in healthy subjects. Spiral readouts with differing duration (26 and 45 ms) but similar resolution were compared with respect to off-resonance performance and image quality. An f0 map-based image correction based on the multifrequency interpolation (MFI) method was implemented and compared to correction using a global frequency shift alone. Estimation of an unknown frequency shift was performed by maximizing a sharpness objective based on the Sobel variance. The apparent full width half at maximum (FWHM) of the myocardial wall on [13 C]bicarbonate was used to estimate blur. RESULTS: Mean myocardial wall FWHM measurements were unchanged with the short readout pre-correction (14.1 ± 2.9 mm) and post-MFI correction (14.1 ± 3.4 mm), but significantly decreased in the long waveform (20.6 ± 6.6 mm uncorrected, 17.7 ± 7.0 corrected, P = .007). Bicarbonate signal-to-noise ratio (SNR) of the images acquired with the long waveform were increased by 1.4 ± 0.3 compared to those acquired with the short waveform (predicted 1.32). Improvement of image quality was observed for all metabolites with f0 correction. CONCLUSIONS: f0 -map correction reduced blur and recovered signal from dropouts, particularly along the posterior myocardial wall. The low image SNR of [13 C]bicarbonate can be compensated with longer duration readouts but at the expense of increased f0 artifacts, which can be partially corrected for with the proposed methods.

Aspirin Use Is Associated With Decreased Mechanical Ventilation, Intensive Care Unit Admission, and In-Hospital Mortality in Hospitalized Patients With Coronavirus Disease 2019.

BACKGROUND: Coronavirus disease-2019 (COVID-19) is associated with hypercoagulability and increased thrombotic risk in critically ill patients. To our knowledge, no studies have evaluated whether aspirin use is associated with reduced risk of mechanical ventilation, intensive care unit (ICU) admission, and in-hospital mortality. METHODS: A retrospective, observational cohort study of adult patients admitted with COVID-19 to multiple hospitals in the United States between March 2020 and July 2020 was performed. The primary outcome was the need for mechanical ventilation. Secondary outcomes were ICU admission and in-hospital mortality. Adjusted hazard ratios (HRs) for study outcomes were calculated using Cox-proportional hazards models after adjustment for the effects of demographics and comorbid conditions. RESULTS: Four hundred twelve patients were included in the study. Three hundred fourteen patients (76.3%) did not receive aspirin, while 98 patients (23.7%) received aspirin within 24 hours of admission or 7 days before admission. Aspirin use had a crude association with less mechanical ventilation (35.7% aspirin versus 48.4% nonaspirin, P = .03) and ICU admission (38.8% aspirin versus 51.0% nonaspirin, P = .04), but no crude association with in-hospital mortality (26.5% aspirin versus 23.2% nonaspirin, P = .51). After adjusting for 8 confounding variables, aspirin use was independently associated with decreased risk of mechanical ventilation (adjusted HR, 0.56, 95% confidence interval [CI], 0.37-0.85, P = .007), ICU admission (adjusted HR, 0.57, 95% CI, 0.38-0.85, P = .005), and in-hospital mortality (adjusted HR, 0.53, 95% CI, 0.31-0.90, P = .02). There were no differences in major bleeding (P = .69) or overt thrombosis (P = .82) between aspirin users and nonaspirin users. CONCLUSIONS: Aspirin use may be associated with improved outcomes in hospitalized COVID-19 patients. However, a sufficiently powered randomized controlled trial is needed to assess whether a causal relationship exists between aspirin use and reduced lung injury and mortality in COVID-19 patients.

Potassium conservation is impaired in mice with reduced renal expression of Kir4.1.

To better understand the role of the inward-rectifying K channel Kir4.1 (KCNJ10) in the distal nephron, we initially studied a global Kir4.1 knockout mouse (gKO), which demonstrated the hypokalemia and hypomagnesemia seen in SeSAME/EAST syndrome and was associated with reduced Na/Cl cotransporter (NCC) expression. Lethality by ~3 wk, however, limits the usefulness of this model, so we developed a kidney-specific Kir4.1 "knockdown" mouse (ksKD) using a cadherin 16 promoter and Cre-loxP methodology. These mice appeared normal and survived to adulthood. Kir4.1 protein expression was decreased ~50% vs. wild-type (WT) mice by immunoblotting, and immunofluorescence showed moderately reduced Kir4.1 staining in distal convoluted tubule that was minimal or absent in connecting tubule and cortical collecting duct. Under control conditions, the ksKD mice showed metabolic alkalosis and relative hypercalcemia but were normokalemic and mildly hypermagnesemic despite decreased NCC expression. In addition, the mice had a severe urinary concentrating defect associated with hypernatremia, enlarged kidneys with tubulocystic dilations, and reduced aquaporin-3 expression. On a K/Mg-free diet for 1 wk, however, ksKD mice showed marked hypokalemia (serum K: 1.5 ± 0.1 vs. 3.0 ± 0.1 mEq/l for WT), which was associated with renal K wasting (transtubular K gradient: 11.4 ± 0.8 vs. 1.6 ± 0.4 in WT). Phosphorylated-NCC expression increased in WT but not ksKD mice on the K/Mg-free diet, suggesting that loss of NCC adaptation underlies the hypokalemia. In conclusion, even modest reduction in Kir4.1 expression results in impaired K conservation, which appears to be mediated by reduced expression of activated NCC.

Genetic factors conferring an increased susceptibility to develop Crohn's disease also influence disease phenotype: results from the IBDchip European Project.

OBJECTIVE: Through genome-wide association scans and meta-analyses thereof, over 70 genetic loci (Crohn's disease (CD) single nucleotide polymorphisms (SNPs)) are significantly associated with CD. We aimed to investigate the influence of CD-SNPs and basic patient characteristics on CD clinical course, and develop statistical models to predict CD clinical course. DESIGN: This retrospective study included 1528 patients with CD with more than 10 years of follow-up from eight European referral hospitals. CD outcomes of interest were ileal (L1), colonic (L2) and ileocolonic disease location (L3); stenosing (B2) or penetrating behaviour (B3); perianal disease; extraintestinal manifestations; and bowel resection. A complicated disease course was defined as stenosing or penetrating behaviour, perianal disease and/or bowel resection. Association between CD-SNPs or patient characteristics and specified outcomes was studied. RESULTS: Several CD-SNPs and clinical characteristics were statistically associated with outcomes of interest. The NOD2 gene was the most important genetic factor, being an independent predictive factor for ileal location (p=2.02 × 10(-06), OR=1.90), stenosing (p=3.16 × 10(-06), OR=1.82) and penetrating (p=1.26 × 10(-02), OR=1.25) CD behaviours, and need for surgery (p=2.28 × e-05, OR=1.73), and as such was also the strongest factor associated with a complicated disease course (p=6.86 × 10(-06), OR=2.96). Immunomodulator (azathioprine/6-mercaptopurine and methotrexate) use within 3 years after diagnosis led to a reduction in bowel stenoses (p=1.48 × 10(-06), OR=0.35) and surgical rate (p=1.71 × 10(-07), OR=0.34). Association between each outcome and genetic scores, created using significant SNPs in the univariate analysis, revealed large differences in the probability of developing fistulising disease (IL23R, LOC441108, PRDM1, NOD2; p=9.64e-4, HR=1.43), need for surgery (IRGM, TNFSF15, C13ORF31, NOD2; p=7.12 × 10(-03), HR=1.35), and stenosing disease (NOD2, JAK2, ATG16L1; p=3.01 × 10(-02), HR=1.29) among patients with low and high score. CONCLUSIONS: This large multicentre cohort study has found several genetic and clinical factors influencing the clinical course of CD. NOD2 and early immunomodulator use are the clinically most meaningful predictors for its clinical course.

TEMPO-conjugated tobacco mosaic virus as a magnetic resonance imaging contrast agent for detection of superoxide production in the inflamed liver.

Superoxide, an anionic dioxygen molecule, plays a crucial role in redox regulation within the body but is implicated in various pathological conditions when produced excessively. Efforts to develop superoxide detection strategies have led to the exploration of organic-based contrast agents for magnetic resonance imaging (MRI). This study compares the effectiveness of two such agents, nTMV-TEMPO and kTMV-TEMPO, for detecting superoxide in a mouse liver model with lipopolysaccharide (LPS)-induced inflammation. The study demonstrates that kTMV-TEMPO, with a strategically positioned lysine residue for TEMPO attachment, outperforms nTMV-TEMPO as an MRI contrast agent. The enhanced sensitivity of kTMV-TEMPO is attributed to its more exposed TEMPO attachment site, facilitating stronger interactions with water protons and superoxide radicals. EPR kinetics experiments confirm kTMV-TEMPO's faster oxidation and reduction rates, making it a promising sensor for superoxide in inflamed liver tissue. In vivo experiments using healthy and LPS-induced inflamed mice reveal that reduced kTMV-TEMPO remains MRI-inactive in healthy mice but becomes MRI-active in inflamed livers. The contrast enhancement in inflamed livers is substantial, validating the potential of kTMV-TEMPO for detecting superoxide in vivo. This research underscores the importance of optimizing contrast agents for in vivo imaging applications. The enhanced sensitivity and biocompatibility of kTMV-TEMPO make it a promising candidate for further studies in the realm of medical imaging, particularly in the context of monitoring oxidative stress-related diseases.

Azurin as a protein scaffold for a low-coordinate nonheme iron site with a small-molecule binding pocket.

The apoprotein of Pseudomonas aeruginosa azurin binds iron(II) to give a 1:1 complex, which has been characterized by electronic absorption, Mössbauer, and NMR spectroscopies, as well as X-ray crystallography and quantum-chemical computations. Despite potential competition by water and other coordinating residues, iron(II) binds tightly to the low-coordinate site. The iron(II) complex does not react with chemical redox agents to undergo oxidation or reduction. Spectroscopically calibrated quantum-chemical computations show that the complex has high-spin iron(II) in a pseudotetrahedral coordination environment, which features interactions with side chains of two histidines and a cysteine as well as the C═O of Gly45. In the (5)A(1) ground state, the d(z(2)) orbital is doubly occupied. Mutation of Met121 to Ala leaves the metal site in a similar environment but creates a pocket for reversible binding of small anions to the iron(II) center. Specifically, azide forms a high-spin iron(II) complex and cyanide forms a low-spin iron(II) complex.

Norepinephrine: a neuromodulator that boosts the function of multiple cell types to optimize CNS performance.

Norepinephrine (NE) is a neuromodulator that in multiple ways regulates the activity of neuronal and non-neuronal cells. NE participates in the rapid modulation of cortical circuits and cellular energy metabolism, and on a slower time scale in neuroplasticity and inflammation. Of the multiple sources of NE in the brain, the locus coeruleus (LC) plays a major role in noradrenergic signaling. Processes from the LC primarily release NE over widespread brain regions via non-junctional varicosities. We here review the actions of NE in astrocytes, microglial cells, and neurons based on the idea that the overarching effect of signaling from the LC is to maximize brain power, which is accomplished via an orchestrated cellular response involving most, if not all cell types in CNS.

Preoperative imaging of glioblastoma patients using hyperpolarized 13C pyruvate: Potential role in clinical decision making.

BACKGROUND: Glioblastoma remains incurable despite treatment with surgery, radiation therapy, and cytotoxic chemotherapy, prompting the search for a metabolic pathway unique to glioblastoma cells.13C MR spectroscopic imaging with hyperpolarized pyruvate can demonstrate alterations in pyruvate metabolism in these tumors. METHODS: Three patients with diagnostic MRI suggestive of a glioblastoma were scanned at 3 T 1-2 days prior to tumor resection using a 13C/1H dual-frequency RF coil and a 13C/1H-integrated MR protocol, which consists of a series of 1H MR sequences (T2 FLAIR, arterial spin labeling and contrast-enhanced [CE] T1) and 13C spectroscopic imaging with hyperpolarized [1-13C]pyruvate. Dynamic spiral chemical shift imaging was used for 13C data acquisition. Surgical navigation was used to correlate the locations of tissue samples submitted for histology with the changes seen on the diagnostic MR scans and the 13C spectroscopic images. RESULTS: Each tumor was histologically confirmed to be a WHO grade IV glioblastoma with isocitrate dehydrogenase wild type. Total hyperpolarized 13C signals detected near the tumor mass reflected altered tissue perfusion near the tumor. For each tumor, a hyperintense [1-13C]lactate signal was detected both within CE and T2-FLAIR regions on the 1H diagnostic images (P = .008). [13C]bicarbonate signal was maintained or decreased in the lesion but the observation was not significant (P = .3). CONCLUSIONS: Prior to surgical resection, 13C MR spectroscopic imaging with hyperpolarized pyruvate reveals increased lactate production in regions of histologically confirmed glioblastoma.

CDH1 gene polymorphisms, smoking, Helicobacter pylori infection and the risk of gastric cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC-EURGAST).

Despite declining incidence rates, gastric cancer (GC) is a major cause of death worldwide. E-Cadherin is an adhesion molecule that is thought to be involved in GC. Germline mutations in the E-Cadherin gene (CDH1) have been identified in hereditary diffuse GC. Also, a promoter polymorphism at position -160 C/A has been suggested to lead to transcriptional down regulation and has been shown to affect GC risk in some studies. However, very little information exists on the GC risk association of other CDH1 polymorphisms and it is unclear whether any associations may be different by GC anatomical sites or histological types. Thus, a case-control study (cases=245/controls=950) nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort was conducted to assess the GC risk association of eight CDH1 gene polymorphisms. None of the CDH1 polymorphisms or haplotypes analysed were associated with GC risk and no differences of effect were observed by Helicobacter pylori infection status. However, three CDH1 polymorphisms in the same haplotype block, including the CDH1-160C/A, interacted with smoking to increase GC risk in smokers but not in never smokers. These findings should be confirmed in larger independent studies.

Schedule shifts, cancer and longevity: good, bad or indifferent?

Prompted by a recent report of the possible carcinogenic effect of shiftwork focusing on the disruption of circadian rhythms, we review studies involving shifts in schedule implemented at varying intervals in unicells, insects and mammals, including humans. Results indicate the desirability to account for a broader-than-circadian view. They also suggest the possibility of optimizing schedule shifts by selecting intervals between consecutive shifts associated with potential side-effects such as an increase in cancer risk. Toward this goal, marker rhythmometry is most desirable. The monitoring of blood pressure and heart rate present the added benefit of assessing cardiovascular disease risks resulting not only from an elevated blood pressure but also from abnormal variability in blood pressure and/or heart rate of normotensive as well as hypertensive subjects.

Seven and 3.5-day rhythms in the incidence of myocardiopathies in Mexico.

BACKGROUND: There is recent evidence about the existence of 7- and 3.5-day rhythms in some biological systems, particularly in human diseases. The objective of this work was to analyze and compare health data from various sources in Mexico to find this rhythm and a plausible explanation. METHODS: We analyzed the hourly number of myocardial infarctions (MI), angina, arrhythmias, hypertension, and heart failure registered at the Clinical Research Department of Hospital de Cardiología of Centro Medico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, in Mexico City for a period of 1 year (1996), with a total of 4947 cases. We used two methods based on the Fast Fourier Transform algorithm to determine the periodicities of this data. RESULTS: A predominant 1-day rhythm was found in the hourly data, and important periodicities of approximately 7- and 3.5-day among other rhythms. These periodicities were also found in other medical data from different sources in Mexico, particularly a long database of MI mortality for the whole country. CONCLUSIONS: The explanation of the 7-day rhythm may be related to the social week of human activity, but the 3.5-day rhythm has no easy explanation. Here we discuss the possibility that these rhythms may be related to environmental conditions, particularly to the solar activity that has periods close to the 3.5 and 7 days. Regardless of the modest number of data, the finding of these rhythms on the incidence of MI and other cardiac-related diseases in Mexico confirms previous investigations concerning medical data from other Mexican health care institutions.

Relationship between clinical features of Crohn's disease and the risk of developing extraintestinal manifestations.

OBJECTIVES: Crohn's disease is frequently associated with extraintestinal manifestations. The aim of this study was to evaluate the degree of association between the development of extraintestinal manifestations, the clinical forms of Crohn's disease according to the Vienna Classification and to the presence of several potential risk factors of the disease. METHODS: One hundred and seventy-three consecutive Crohn's disease patients were studied. Sex, smoking habits, previous Crohn's disease-related surgery, family history of Crohn's disease, steroid dependency, steroid resistance and the presence of at least one mutant allele in any of the three considered variants of CARD15 gene were considered as potential risk factors. The Vienna Classification was applied, and the presence of extraintestinal manifestations was evaluated. RESULTS: A total of 61 (35.3%) patients developed extraintestinal manifestations. They were more frequently seen in women than in men (41.1 vs. 26.7%), (odds ratio 1.92, 95% confidence interval: 0.99-3.70; P=0.05) and in steroid-dependent patients than in steroid responders (61.1 vs. 28.5%), (odds ratio 3.94, 95% confidence interval: 1.83-8.49; P<0.01). No relationship was found in general between the extraintestinal manifestations of Crohn's disease and smoking habits, previous Crohn's disease-related surgery, a family history of Crohn's disease, steroid resistance and CARD15 mutations. Such relationships were, however, detected for some individual extraintestinal manifestations as between both smoking habits (odds ratio 9.09, 95% confidence interval: 1.15-71.66; P<0.05) and the G908R CARD15 mutation (odds ratio 4.76, 95% confidence interval: 1.11-20.43; P<0.05), respectively, and erythema nodosum. Patients with any colonic involvement of Crohn's disease (L2+L3) suffered from extraintestinal manifestations of the disease more frequently than patients without colonic involvement (42.7 vs. 25.9%, respectively; odds ratio 2.12, 95% confidence interval: 1.10-4.07; P<0.05). CONCLUSIONS: Female gender, steroid-dependency and colonic involvement are associated with the risk of developing extraintestinal manifestations of Crohn's disease.

[Design of an atrial fibrillation and embolic risk registry in Mexico: CARMEN-AF]. / Diseño de un registro de fibrilación auricular y riesgo embólico en México: CARMEN-AF.

OBJECTIVE: Atrial fibrillation (AF) is one of the most common arrhythmias, and its prevalence increase with age. It is associated with high risk of stroke. The prevention of such thromboembolism is done with oral anticoagulants, which in our country seem to be underused. CARMEN-AF registry aims primarily to determine the current status of thromboprophylaxis of non-valvular AF in Mexico. A secondary objective is to know the morbidity and mortality associated with non-valvular AF in at least one year of follow-up. METHODS: CARMEN-AF registry is an observational, longitudinal, multicenter, and national survey about the use of oral anticoagulants in patients with non-valvular AF. Patients 18years old or older, diagnosed with AF during the last 6months, and with at least one risk factor of thromboembolism based in the CHA2DS2-Vasc score are being selected. Demographic and clinical data will be collected during the visits to their usual clinic with a follow-up of 2years. The recruitment began on September 19, 2014, and the inclusion of the last patient is expected on September 18, 2016. According to the reported incidence of AF globally and taking into account the total Mexican population, the inclusion of 1,200 patients is estimated. CONCLUSIONS: The Atrial Fibrillation and Embolic Risk Registry (CARMEN-AF) will reveal the current status of thromboprophylaxis in patients with non-valvular AF, and will allow to get an overview of the national and international clinical practice guidelines accomplishment in this area.

The Mitochondrial Unfolded Protein Response Protects against Anoxia in Caenorhabditis elegans.

The mitochondrial unfolded protein response (UPRmt) is a surveillance pathway that defends proteostasis in the "powerhouse" of the cell. Activation of the UPRmt protects against stresses imposed by reactive oxygen species, respiratory chain deficits, and pathologic bacteria. Consistent with the UPRmt's role in adaption, we found that either its pharmacological or genetic activation by ethidium bromide (EtBr) or RNAi of the mitochondrial AAA-protease spg-7 was sufficient to reduce death in an anoxia-based Caenorhabditis elegans model of ischemia-reperfusion injury. The UPRmt-specific transcription factor atfs-1 was necessary for protection and atfs-1 gain-of-function (gf) mutants were endogenously protected from both death and dysfunction. Neurons exhibited less axonal degeneration following non-lethal anoxia-reperfusion (A-R) when the UPRmt was pre-activated, and consistent with the concept of mitochondrial stress leading to cell non-autonomous (ie. "remote") effects, we found that restricted activation of the UPRmt in neurons decreased A-R death. However, expression of the atfs-1(gf) mutant in neurons, which resulted in a robust activation of a neuronal UPRmt, did not upregulate the UPRmt in distal tissues, nor did it protect the worms from A-R toxicity. These findings suggest that remote signaling requires additional component(s) acting downstream of de facto mitochondrial stress.

Lack of association of IL-12 p40 gene polymorphism with peptic ulcer disease.

Interleukin 12 (IL-12) is a proinflammatory cytokine composed by two chains, p40 and p35, that plays a key role in the promotion of a Th1 immune response in the gastrointestinal mucosa. An enhanced expression of IL-12 mRNA in gastric mucosa has been reported in individuals infected by Helicobacter pylori. The aim of our study was to assess whether a functional polymorphism located at position 1188 (A-->C) of the IL-12 p40 (IL12B) gene is associated with the susceptibility and clinical features of peptic ulcer disease. Genotyping of 184 unrelated white Spanish patients with peptic ulcer and 107 healthy controls was performed by polymerase chain reaction and restriction fragment length polymorphism. Helicobacter pylori status and nonsteroidal antiinflammatory drugs use were studied in patients and controls. There were no significant differences in carriage, genotype, and allele frequencies of the IL-12 p40 gene polymorphism between patients with peptic ulcer and controls. Moreover, no differences were found with respect to the localization of the ulcer, Helicobacter pylori status, nonsteroidal antiinflammatory drug use, age, sex, bleeding episodes, and family history of peptic ulcer. Our data reveal that the IL12B 1188 (A-->C) gene polymorphism is not involved in defining the genetic basis of the susceptibility to and final outcome of peptic ulcer disease.

Autoantibodies and histogenesis of celiac disease.

OBJECTIVE: Autoantibodies are used as markers for celiac disease (CD) identifying patients with mucosal lesions. The purpose of this study was to evaluate the sensitivity and role of the autoantibodies such as IgA antiendomysium (EMA), IgA antigliadin (AGA) and the IgA antitissue transglutaminase (tTGA) in histogenesis of celiac disease. METHODS: Seventy-nine cases including 30 untreated celiacs, 5 celiacs on gluten-free diet (GFD), 41 first degree relatives and 3 non-relatives suspected for CD were investigated. Three untreated celiacs with IgA deficiency were excluded from this study group. IgA antibodies to tTGA were determined by ELISA, as described before. Twelve of 41 relatives and 2 cases of non relatives suspected with positive serology underwent a small intestinal biopsy. Results were correlated with the degrees of abnormality of the intestinal mucosa in patients with CD. Intestinal biopsies obtained from study population were evaluated for histological quantification. RESULTS: Celiacs and suspected cases with positive EMA/AGA and or tTGA showed shorter villi (p < 0.007) and/or a higher number of intraepithelial lymphocytes (IEL) (p < 0.035). The sensitivity of serology (EMA, AGA, tTGA) in patients with Marsh IIIc was 100%. However, in patients with Marsh IIIa the sensitivity for EMA, AGA, and tTGA was 40%, 50% and 20% respectively. CONCLUSIONS: The appearance of antibodies is related to the degree of mucosal infiltration by IELs. Although tTGA, like EMA provide a highly sensitive parameter for the detection of celiacs with severe mucosal damage, it appears to be less sensitive (even less than AGA) in celiac patients with milder histopathological abnormalities. However, it should be recognized that the substantial part of the celiac population present with these milder forms of mucosal abnormalities. Using tTGA as a single test in screening may result in missing up to 60-70% of celiacs with mild mucosal abnormalities. Combination with other screening tests (at least with AGA) is essential and strongly recommended