Nanoscale density variations induced by high energy heavy ions in amorphous silicon nitride and silicon dioxide.

The cylindrical nanoscale density variations resulting from the interaction of 185 MeV and 2.2 GeV Au ions with 1.0 µm thick amorphous SiN x :H and SiO x :H layers are determined using small angle x-ray scattering measurements. The resulting density profiles resembles an under-dense core surrounded by an over-dense shell with a smooth transition between the two regions, consistent with molecular-dynamics simulations. For amorphous SiN x :H, the density variations show a radius of 4.2 nm with a relative density change three times larger than the value determined for amorphous SiO x :H, with a radius of 5.5 nm. Complementary infrared spectroscopy measurements exhibit a damage cross-section comparable to the core dimensions. The morphology of the density variations results from freezing in the local viscous flow arising from the non-uniform temperature profile in the radial direction of the ion path. The concomitant drop in viscosity mediated by the thermal conductivity appears to be the main driving force rather than the presence of a density anomaly.

Length-dependent thermopower of highly conducting Au-C bonded single molecule junctions.

We report the simultaneous measurement of conductance and thermopower of highly conducting single-molecule junctions using a scanning tunneling microscope-based break-junction setup. We start with molecular backbones (alkanes and oligophenyls) terminated with trimethyltin end groups that cleave off in situ to create junctions where terminal carbons are covalently bonded to the Au electrodes. We apply a thermal gradient across these junctions and measure their conductance and thermopower. Because of the electronic properties of the highly conducting Au-C links, the thermoelectric properties and power factor are very high. Our results show that the molecular thermopower increases nonlinearly with the molecular length while conductance decreases exponentially with increasing molecular length. Density functional theory calculations show that a gateway state representing the Au-C covalent bond plays a key role in the conductance. With this as input, we analyze a series of simplified models and show that a tight-binding model that explicitly includes the gateway states and the molecular backbone states accurately captures the experimentally measured conductance and thermopower trends.

Macular optical coherence tomography findings and GPR143 mutations in patients with ocular albinism.

The aim of this study was to describe macular findings using spectral-domain optical coherence tomography (SD-OCT) in patients with ocular albinism (OA) and their carrier mothers, and to identify the frequency of GPR143 gene mutations in these patients. The study included five patients with a clinical diagnosis of OA. SD-OCT of the macular area was performed in both patients and their mothers. The anatomical characteristics of the macula and retinal pigment epithelium (RPE), patterns of autofluorescence and infrared imaging were analyzed. Polymerase chain reaction amplification of the complete coding sequence of GPR 143 was performed and subsequently analyzed by direct sequencing in patients and their possible carrier mothers. SD-OCT images revealed the presence of inner retinal layers in the fovea, an abnormal disposition of the Henle layer and a lack of thickening in the perifoveal area. We found increased thickness in the RPE to the outer segment and in the outer segment to the outer nuclear layer that is associated with increased visual acuity. Autofluorescence images revealed an absence of normal hipoautofluorescence in the fovea. No changes were observed in the images of their carrier mothers. Mutation screening and sequence analysis of the GPR 143 gene revealed a novel pathological mutation in two patients. Abnormalities in the macula were observed in all patients. SD-OCT is a useful tool for the assessment of patients with OA. No changes were observed in the SD-OCT of carrier mothers. Only two patients had the GPR143 gene mutation.

[Functional dyspepsia and the satiety test: its usefulness in clinical practice]. / Dispepsia funcional y test de saciedad: utilidad en la práctica clínica.

INTRODUCTION: According to the Rome III Criteria, functional dyspepsia (FD) is classified as postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS). On the other hand, the satiety test (ST) has been used to evaluate gastric accommodation and emptying, distinguishing healthy individuals from those with dyspepsia. AIMS: To determine whether the ST can distinguish dyspeptic individuals from healthy ones and to evaluate its usefulness in differentiating the two FD subtypes. METHODS: Adults with FD were consecutively enrolled in a cross-sectional study within the time frame of August 2011 and October 2012. Healthy subjects participated as controls. The ST consisted of the intake of a nutritional supplement (Fortisip®, Nutricia Bagó®) at a constant speed; satiety was graded at 5-minute intervals (1 to 5 points). Intake was suspended when the maximum score was reported. The total ingested volume and caloric intake was recorded and the Mann-Whitney U test was used in the statistical analysis. RESULTS: The study included 39 dyspeptic patients and 20 control individuals. The patients were predominantly women (84.6 vs. 25%; p < 0.0001) and they were similar in age (39.59 ± 13.53 vs. 34.70 ± 9.85 years) and BMI (24.32 ± 3.52 vs. 25.82 ± 3.34 kg/m2) with respect to the controls. The FD subtype percentages were PDS: 61%, EPS: 31%, and Mixed syndrome: 8%. There was a lower ingested volume and caloric intake on the part of the dyspeptic patients (185 vs. 300 ml and 277 vs. 520 Kcal, respectively. Both: P<.001). No differences in the ST were observed between the two pure dyspepsia subtypes. CONCLUSIONS: There was a difference in the ST between healthy individuals and those with dyspepsia, but the ingested volume and caloric intake in the two FD subtypes were similar.

Better quality of life and reduced fecal incontinence in rectal cancer patients with the watch-and-wait follow-up strategy.

INTRODUCTION: The watch-and-wait (WW) strategy is an alternative to anterior resection in patients with rectal cancer (RC) that have had a complete clinical response to neoadjuvant treatment. Few reports describe the quality of life and functional anorectal disorders (FADs) in that population. AIM: To analyze and compare the FADs and quality of life in patients with locally advanced adenocarcinoma of the rectum treated with neoadjuvant therapy, divided into two different strategy groups: group 1 (G1), WW; and group 2 (G2), anterior resection. MATERIALS AND METHODS: Thirty patients (G1: n = 20 and G2: n = 10) that had finished neoadjuvant therapy at least 12 months prior were included. Mean patient age was 59.5 years (range: 41-79) and 15 of the patients were men. The FADs were evaluated through: a) clinical history, b) 21-day bowel diary, c) Jorge and Wexner fecal incontinence scale, d) anorectal manometry (ARM), and fecal incontinence quality of life scale (FIQL). RESULTS: Bowel diary: fecal incontinence (40%) and urge to defecate (45%) in G1 vs. fecal incontinence (60%) and urge to defecate (30%) in G2, with no significant differences (p = NS). Fecal incontinence scale: fecal incontinence in G1 was significantly less severe than that in G2 (median 6.5 points vs. 13 points [p = 0.0142]). ARM: no differences between the two groups. Quality of life: significantly different between the two groups (FIQL/G1: 3.7 vs. FIQL/G2: 2.8; p < 0.03). CONCLUSIONS: The WW follow-up strategy in patients with locally advanced rectal cancer was associated with better quality of life and reduced fecal incontinence.

Atomic-scale control of electron transport through single molecules.

Tin-phthalocyanine molecules adsorbed on Ag(111) were contacted with the tip of a cryogenic scanning tunneling microscope. Orders-of-magnitude variations of the single-molecule junction conductance were achieved by controllably dehydrogenating the molecule and by modifying the atomic structure of the surface electrode. Nonequilibrium Green's function calculations reproduce the trend of the conductance and visualize the current flow through the junction, which is guided through molecule-electrode chemical bonds.

Better quality of life and reduced fecal incontinence in rectal cancer patients with the watch-and-wait follow-up strategy. / Mejor calidad de vida y menor incontinencia fecal en pacientes con cáncer de recto con la estrategia de seguimiento watch and wait.

INTRODUCTION: The watch-and-wait (WW) strategy is an alternative to anterior resection in patients with rectal cancer (RC) that have had a complete clinical response to neoadjuvant treatment. Few reports describe the quality of life and functional anorectal disorders (FADs) in that population. AIM: To analyze and compare the FADs and quality of life in patients with locally advanced adenocarcinoma of the rectum treated with neoadjuvant therapy, divided into two different strategy groups: group 1 (G1), WW; and group 2 (G2), anterior resection. MATERIALS AND METHODS: Thirty patients (G1: n = 20 and G2: n = 10) that had finished neoadjuvant therapy at least 12 months prior were included. Mean patient age was 59.5 years (range: 41-79) and 15 of the patients were men. The FADs were evaluated through: a) clinical history, b) 21-day bowel diary, c) Jorge and Wexner fecal incontinence scale, d) anorectal manometry (ARM), and fecal incontinence quality of life scale (FIQL). RESULTS: Bowel diary: fecal incontinence (40%) and urge to defecate (45%) in G1 vs. fecal incontinence (60%) and urge to defecate (30%) in G2, with no significant differences (p = NS). Fecal incontinence scale: fecal incontinence in G1 was significantly less severe than that in G2 (median 6.5 points vs. 13 points [p = 0.0142]). ARM: no differences between the two groups. Quality of life: significantly different between the two groups (FIQL/G1: 3.7 vs. FIQL/G2: 2.8; p < 0.03). CONCLUSIONS: The WW follow-up strategy in patients with locally advanced rectal cancer was associated with better quality of life and reduced fecal incontinence.

Effect of Bifidobacterium infantis NLS super strain in symptomatic coeliac disease patients on long-term gluten-free diet - an exploratory study.

Bifidobacterium infantis NLS super strain (B. infantis NLS-SS) was previously shown to alleviate gastrointestinal symptoms in newly diagnosed coeliac disease (CD) patients consuming gluten. A high proportion of patients following a gluten-free diet experiences symptoms despite dietary compliance. The role of B. infantis in persistently symptomatic CD patients has not been explored. The aim of the study was to evaluate the effect of B. infantis NLS-SS on persistent gastrointestinal symptoms in patients with CD following a long-term GFD. We conducted a randomised, cross-over, double-blind, placebo-controlled trial in symptomatic adult CD patients on a GFD for at least two years. After one-week run-in, patients were randomised to B. infantis NLS-SS or placebo for 3 weeks with cross-over after a 2-week wash-out period. We estimated changes (Δ) in celiac symptom index (CSI) before and after treatment. Stool samples were collected for faecal microbiota analysis (16S rRNA sequencing). Gluten immunogenic peptide (GIP) excretion in stool and urine samples was measured at each study period. Eighteen patients were enrolled; six patients were excluded due violations in protocol. For patients with the highest clinical burden, CD symptoms were lower in probiotic than in placebo treatment (P=0.046). B. infantis and placebo treated groups had different microbiota profiles as assessed by beta diversity clustering. In probiotic treated groups, we observed an increase in abundance of B. infantis. Treatment with B. infantis was associated with decreased abundance of Ruminococcus sp. and Bifidobacterium adolescentis. GIP excretion in stools and urine was similar at each treatment period. There were no differences in adverse effects between the two groups. B. infantis NLS-SS improves specific CD symptoms in a subset of highly symptomatic treated patients (GFD). This is associated with a shift in stool microbiota profile. Larger studies are needed to confirm these findings. ClinicalTrials.gov: NCT03271138.

Stable compounds of helium and neon: he@c60 and ne@c60.

It is demonstrated that fullerenes, prepared via the standard method (an arc between graphite electrodes in a partial pressure of helium), on heating to high temperatures release (4)He and (3)He. The amount corresponds to one (4)He for every 880,000 fullerene molecules. The (3)He/(4)He isotopic ratio is that of tank helium rather than that of atmospheric helium. These results convincingly show that the helium is inside and that there is no exchange with the atmosphere. The amount found corresponds with a prediction from a simple model based on the expected volume of the cavity. In addition, the temperature dependence for the release of helium implies a barrier about 80 kilocalories per mole. This is much lower than the barrier expected from theory for helium passing through one of the rings in the intact structure. Amechanism involving reversibly breaking one or more bonds to temporarily open a "window" in the cage is proposed. A predicted consequence of this mechanism is the incorporation of other gases while the "window" is open. This was demonstrated through the incorporation of (3)He and neon by heating fullerene in their presence.

Modelling energy level alignment at organic interfaces and density functional theory.

A review of our theoretical understanding of the band alignment at organic interfaces is presented with particular emphasis on the metal/organic (MO) case. The unified IDIS (induced density of interface states) and the ICT (integer charge transfer) models are reviewed and shown to describe qualitatively and semiquantitatively the barrier height formation at those interfaces. The IDIS model, governed by the organic CNL (charge neutrality level) and the interface screening includes: (a) charge transfer across the interface; (b) the "pillow" (or Pauli) effect associated with the compression of the metal wavefunction tails; and (c) the molecular dipoles. We argue that the ICT-model can be described as a limiting case of the unified IDIS-model for weak interface screening. For a fully quantitative understanding of the band alignment at organic interfaces, use of DFT (density functional theory) or quantum chemistry methods is highly desirable. In this Perspective review, we concentrate our discussion on DFT and show that conventional LDA or GGA calculations are limited by the "energy gap problem of the organic materials", because the LDA (or GGA) Kohn-Sham energy levels have to be corrected by the self-interaction energy of the corresponding wavefunction, to provide the appropriate molecule transport energy gap. Image potential and polarization effects at MO interfaces tend to cancel these self-interaction corrections; in particular, we show that for organic molecules lying flat on Cu and Ag, these cancellations are so strong that we can rely on conventional DFT to calculate their interface properties. For Au, however, the cancellations are weaker making it necessary to go beyond conventional DFT. We discuss several alternatives beyond conventional LDA or GGA. The most accurate approach is the well-known GW-technique, but its use is limited by its high demanding computer time. In a very simple approach one can combine conventional DFT with a "scissor" operator which incorporates self-interaction corrections and polarization effects in the organic energy levels. Hybrid potentials combined with conventional DFT represent, probably, the best alternative for having a simple and accurate approach for analyzing organic interfaces. The problem then is to find an appropriate one for both the metal and the organic material in a plane-wave formulation; we show, however, how to overcome this difficulty using a local-orbital basis formulation. As examples of these alternatives, we present some DFT-calculations for several organic interfaces, using either the scissor operator or a hybrid potential, which can be interpreted in terms of the unified IDIS-model.

Systematic review and meta-analysis of observational studies on the prevalence of fractures in coeliac disease.

BACKGROUND/AIMS: Evidence of an increased bone fracture risk in coeliac disease is on debate. Our aim was to review systematically the current published information on fractures in coeliac disease and to perform a meta-analysis. METHODS: Case-control and cohort designs were identified by searching MEDLINE (1966-April 2007) and LILACS (1982-April 2007). Participants were adult coeliac disease patients of any sex and the outcome measure was the presence of any fracture. Studies were screened for inclusion by two authors who independently extracted the data. Methodological quality was assessed using the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology Statement) recommendations. Data were analysed using the RevMan Analyses statistical package in Review Manager (version 4.2.8) and reported as pooled odds ratio using a random effect model. Heterogeneity was investigated (standard chi(2) test) and sensitivity analysis was performed based on the reported quality and design type. RESULTS: While 60 of 405 studies met the initial screening criteria, only 8 met inclusion criteria after detailed review. These studies evaluated a total of 20,955 coeliac disease patients having 1819 (8.7%) fractures and 96,777 controls with 5955 (6.1%) fractures (pooled odds ratio=1.43; 95% confidence interval 1.15-1.78) with considerable heterogeneity among studies (p<0.00001). CONCLUSIONS: Our meta-analysis confirms a significant association between bone fractures and coeliac disease. However, qualitative and quantitative differences among studies were evident. Further research is necessary to investigate the relevance of this heterogeneity.

[Case report. Patient with varicocele & oligozoospermia with Y chromosome microdeletion: AZFb+c]. / Aportación de un caso. Paciente con varicocele y oligozoospermia, con microdeleción en cromosoma Y: AZFb+c.

The 13-18% of the couples in reproductive age gets to present some kind of fertility problem, the male factor participates in near 50% of the cases. The microdeletions in the Yq chromosome occupy single the 7,6%; severe oligozoospermia and azoospermia are related with these alterations. The structure of region AZF of Yq is divided in AZFa, AZFb, AZFc and AZFd. The microdeletions can be simple or combined, the microdeletion AZFc (59-65%) is the commonest. In cases with severe oligozoospermia (or azoospermia), study of microdeletions in Y chromosome is suggested. ICSI with selection of sex, would be the treatment adapted in these cases, is in phase of study.

Familial exudative vitreoretinopathy: A report of an asymptomatic case with autosomal dominant inheritance detected using FZD4 molecular analysis. / Vitreorretinopatía exudativa familiar, reporte de un caso asintomático con herencia autosómica dominante, detectado mediante análisis molecular de FZD4.

OBJECTIVE: To report a familial case of Familial Exudative Vitreoretinopathy (FEVR) with an autosomal dominant inheritance pattern identified with the molecular analysis of FZD4. CASE REPORT: The proband is a 13 year-old boy who consulted for low vision. Fundus examination revealed a peripheral avascular zone and macular dragging, consistent with FEVR. Molecular analysis demonstrated a mutation of FZD4 in DNA from both the patient and his asymptomatic mother. DISCUSSION: This familial case was identified with the molecular analysis of FZD4 and shows the importance to explore first degree relatives in a sporadic FEVR case.

Sexual comparisons in immune ability, survival and parasite intensity in two damselfly species.

Recent evolutionary studies have suggested that females have a more robust immune system than males. Using two damselfly species (Hetaerina americana and Argia tezpi), we tested if females produced higher immune responses (as phenoloxidase and hydrolytic enzymes), had a higher survival (using a nylon implant inserted in the abdomen and measuring survival after 24h) and fewer parasites (gregarines and water mites) than males. We also tested whether immune differences should emerge in different body areas (thorax vs. abdomen) within each sex with the prediction that only females will differ with the abdomen having a higher immune response than their thorax since the former area, for ecological and physiological reasons, may be a target zone for increased immune investment. Animals were adults of approximately the same age. In both species, females were more immunocompetent than males, but only in H. americana females were immune responses greater in the abdomen than in the thorax. However, there were no differences in survival and parasite intensity or the probability of being parasitised between the sexes in either of the two species. Thus, this study lends partial support to the principle that females are better at defending than males despite the null difference in parasitism and survival.

Molecular Epidemiology of Mycobacterium bovis in Humans and Cattle.

Bovine tuberculosis (bTB), caused by Mycobacterium bovis (M. bovis), is a serious re-emerging disease in both animals and humans. The evolution of the Multi- and Extensively drug-resistant M. bovis strains (MDR-TB and XDR-TB) represents a global threat to public health. Worldwide, the disease is responsible for great economic losses in the veterinary field, serious threat to the ecosystem, and about 3.1% of human TB cases, up to 16% in Tanzania. Only thorough investigation to understand the pathogen's epidemiology can help in controlling the disease and minimizing its threat. For this purpose, various tools have been developed for use in advanced molecular epidemiological studies of bTB, either alone or in combination with standard conventional epidemiological approaches. These techniques enable the analysis of the intra- and inter-species transmission dynamics of bTB. The delivered data can reveal detailed insights into the source of infection, correlations among human and bovine isolates, strain diversity and evolution, spread, geographical localization, host preference, tracing of certain virulence factors such as antibiotic resistance genes, and finally the risk factors for the maintenance and spread of M. bovis. They also allow for the determination of epidemic and endemic strains. This, in turn, has a significant diagnostic impact and helps in vaccine development for bTB eradication programs. The present review discusses many topics including the aetiology, epidemiology and importance of M. bovis, the prevalence of bTB in humans and animals in various countries, the molecular epidemiology of M. bovis, and finally applied molecular epidemiological techniques.

Pharmacokinetics of a F(ab')2 scorpion antivenom in healthy human volunteers.

This paper presents the first study of F(ab')2 scorpion antivenom pharmacokinetics in humans. We have studied the pharmacokinetics of an antiscorpion venom preparation (Alacramyn) in eight human healthy volunteers. The fabotherapic was administered as a 47.5 mg i.v. bolus. Blood samples were drawn at 0, 5, 15, 30, 45, 60, 90, 120, 180 and 360 min after antivenom administration. Subsequently, the volunteers made seven visits to the hospital. Four of them at 24 h intervals, one at day 10, and one at day 21. We measured antivenom plasmatic concentrations using a specific high sensitivity ELISA method for F(ab')2. The time course of F(ab')2 in serum of seven subjects was well described by a lineal combination of three exponential components; a four exponential component model was necessary to fit the eighth subject. The most significant antivenom pharmacokinetic parameters determined were: AUC(infinity)=596.9 (369.3, 891.2) mg h l(-1); V(c) = 3.1 (2.3, 4.3)l; V(ss) = 15.4 (12.8, 39.9)l; MRT = 250.0 (218.8, 310.2) h; CL = 96.6 (58.0, 139.2) ml h(-1); t(1/2,tau1) (also called t(1/2,alpha)) = 0.25 (0.13, 0.37) h; t(1/2,tau(z)) (corresponding to the slowest component) = 161.3 (141.0, 212.0) h.

Experience of a successful pediatric liver transplant program in Mexico.

Orthotopic liver transplantation (OLT) has been very difficult to develop in Mexico and for many years its occurrence was anecdotal. This report presents the results of a pediatric liver transplant program, analyzing the variables that affect outcomes. Between June 1998 and March 2004, 35 OLT were performed in 34 recipients including 80% cadaveric whole-organ grafts and 20% segmental grafts, with 11% from cadaveric and 9% from living donors. Most of the recipients were infants or toddlers weighing less than 15 kg. There was only 1 case of arterial thrombosis (2.8%); the graft was saved with a Kasai procedure. Biliary complications were present in 22% of cases, all resolved with reoperations. Posttransplant cytomegalovirus infection or reactivation (28%), acute rejection (25%), or posttransplant lymphoproliferative disorders (5.7%) were not a cause of graft or patient loss. Overall, 1- and 5-year patient survival rates are 77.1% and 74.2%, respectively; however, when the 1998-2000 cohort was compared with the 2001-2004 cohort, there was a significant difference in survival (P = .004). The 1-year patient survival for the later group is 91.6%. We performed the first successful living donor liver transplantation and the first simultaneous liver-kidney transplantation in a child in our country. Our results demonstrate that pediatric liver transplantation is a feasible undertaking in Mexico, with survival rates comparable to those of foreign centers.

Body composition and bone mineral density in untreated and treated patients with celiac disease.

Body composition and bone mineral density (BMD) were studied by X-ray absorptiometry in 20 untreated and 12 treated women with celiac disease, as well as in 85 age-matched control women. Untreated patients had a significantly lower body weight, fat mass, lean tissue mass and BMD at the lumbar spine and total skeleton compared to controls (p < 0.001 for all parameters). Treated patients had also a significantly lower body weight (p < 0.01) fat mass (p < 0.05) and bone mineral density at lumbar spine and total skeleton (p < 0.05) compared with controls, but lean tissue mass was not diminished. However, treated patients had a significantly higher body weight, fat mass and BMD of the total skeleton compared with untreated celiac patients (p < 0.01 for all parameters). Serum alkaline phosphatase levels were increased in untreated patients but serum 250HD was normal. In conclusion, celiac disease causes a global and almost universal reduction of fat mass and BMD. The results of this cross-sectional study suggest that osteopenia does not seem to be completely restored by adequate treatment. Alteration of vitamin D metabolism was not the cause of osteopenia in the majority of patients.

Antibodies to human recombinant tissue transglutaminase may detect coeliac disease patients undiagnosed by endomysial antibodies.

BACKGROUND: The screening and diagnosis of coeliac disease have been simplified by the advent of new serological tools. AIM: To assess the clinical utility of a newly developed kit for antibodies to human recombinant tissue transglutaminase (hu-anti-tTG) in a large population of patients undergoing intestinal biopsy for suspected intestinal disorders. METHODS: We evaluated 426 serum samples from consecutive adult patients (250 from untreated coeliac disease patients and 176 from individuals in whom a diagnosis of coeliac disease had been excluded), obtained at the time of intestinal biopsy. Samples were tested for immunoglobulin A (IgA) hu-anti-tTG by enzyme-linked immunoabsorbent assay, IgA endomysial antibodies (EmA) by indirect immunofluorescence and IgA and IgG antigliadin antibodies by enzyme-linked immunoabsorbent assay. A sub-group of samples was also assessed for a guinea-pig-based anti-tissue transglutaminase. RESULTS: According to the cut-off for hu-anti-tTG, the sensitivity, specificity and positive and negative predictive values were 91%, 96%, 97% and 87%, respectively. Simultaneous determination of EmA showed values of 86%, 100%, 100% and 83% for the same parameters. Although 19 coeliac disease patients (7.6%) were negative for EmA and hu-anti-tTG, both tests rendered superior statistical values to antigliadin antibody tests. At diagnosis, IgA deficiency was detected in 11 patients, but both assays were able to detect samples with mild to moderate deficiency. The comparison of hu-anti-tTG with EmA showed excellent concordance between the tests (kappa statistic, 0.85). Discordance was observed in 20 samples from coeliac disease patients (8%) and in nine samples from controls (5%). Fifteen samples had an EmA-negative but hu-anti-tTG-positive serology, and five showed the converse pattern. Comparison of human recombinant and guinea-pig tests showed concordant results in 96% of cases. CONCLUSIONS: The quantitative determination of hu-anti-tTG type IgA using a commercial enzyme-linked immunoabsorbent assay kit was highly sensitive and specific for the detection of coeliac disease. Our results in a large population of patients with a clinical condition suggestive of the disorder demonstrated that the test can be used to detect a substantial number of patients otherwise unrecognized by IgA EmA.

Long-term effect of gluten restriction on bone mineral density of patients with coeliac disease.

AIM: To assess the long-term effect of a gluten-free diet on bone mineral density of adults with untreated coeliac disease. METHODS: Bone mineral density was assessed at baseline and after a mean duration of 37 months of treatment in 25 unselected newly diagnosed coeliac patients. RESULTS: At baseline, osteopenia (> -1 s.d. below normal) was evident in the lumbar spine and total skeleton in 18 (72%) and 21 (84%) patients, respectively. At the end of the study, bone density had increased (mean bone mass Z-score increase: Z-score +1.0 for the lumbar spine and +1.1 for total skeleton) in 22 and 23 patients, respectively. Patients who adhered to strict gluten restriction (n = 15) demonstrated a similar bone remineralization in the spine than those patients with partial compliance (n = 10) (mean Z-score increase: +1.0, in both areas). A greater mean annual change in Z-score in the total skeleton was noted in patients who followed strict gluten restriction (0.4 +/- 0.1) respect to those with partial compliance (0.3 +/- 0.1); however, this difference was not statistically significant. Pre-menopausal women had significantly greater remineralization that post-menopausals (P > 0.05). Remineralization showed an inverse correlation with the degree of basal osteopenia (r = -0.525; P < 0.002). CONCLUSIONS: Long-term treatment with gluten-free diet produces a significant improvement in bone density in coeliac patients. Remineralization was more pronounced in patients who better comply with gluten-free diet, in pre-menopausal women and in patients with the lowest baseline bone mineral density.