60 research outputs found
Bio-physical characteristics of gastrointestinal mucosa of celiac patients: comparison with control subjects and effect of gluten free diet-
<p>Abstract</p> <p>Background</p> <p>Intestinal mucosa is leaky in celiac disease (CD), and this alteration may involve changes in hydrophobicity of the mucus surface barrier in addition to alteration of the epithelial barrier. The aims of our study were i) to compare duodenal hydrophobicity as an index of mucus barrier integrity in CD patients studied before (n = 38) and during gluten- free diet (GFD, n = 68), and in control subjects (n = 90), and ii) to check for regional differences of hydrophobicity in the gastro-intestinal tract.</p> <p>Methods</p> <p>Hydrophobicity was assessed by measurement of contact angle (CA) (Rame Hart 100/10 goniometer) generated by a drop of water placed on intestinal mucosal biopsies.</p> <p>Results</p> <p>CA (mean ± SD) of distal duodenum was significantly lower in CD patients (56° ± 10°)) than in control subjects (69° ± 9°, p < 0.0001), and persisted abnormal in patients studied during gluten free diet (56° ± 9°; p < 0.005). CA was significantly higher (62° ± 9°) in histologically normal duodenal biopsies than in biopsies with Marsh 1-2 (58° ± 10°; p < 0.02) and Marsh 3 lesions (57° ± 10°; p < 0.02) in pooled results of all patients and controls studied. The order of hydrofobicity along the gastrointestinal tract in control subjects follows the pattern: gastric antrum > corpus > rectum > duodenum > oesophagus > ileum.</p> <p>Conclusions</p> <p>We conclude that the hydrophobicity of duodenal mucous layer is reduced in CD patients, and that the resulting decreased capacity to repel luminal contents may contribute to the increased intestinal permeability of CD. This alteration mirrors the severity of the mucosal lesions and is not completely reverted by gluten-free diet. Intestinal hydrophobicity exhibits regional differences in the human intestinal tract.</p
The influence of early aging on eye movements during motor simulation
Movement based interventions such as imagery and action observation are used increasingly to support physical rehabilitation of adults during early aging. The efficacy of these more covert approaches is based on an intuitively appealing assumption that movement execution, imagery and observation share neural substrate; alteration of one influences directly the function of the other two. Using eye movement metrics this paper reports findings that question the congruency of the three conditions. The data reveal that simulating movement through imagery and action observation may offer older adults movement practice conditions that are not constrained by the age-related decline observed in physical conditions. In addition, the findings provide support for action observation as a more effective technique for movement reproduction in comparison to imagery. This concern for imagery was also seen in the less congruent temporal relationship in movement time between imagery and movement execution suggesting imagery inaccuracy in early aging
Mechanisms and management of loss of response to anti-TNF therapy for patients with Crohn's disease: 3-year data from the prospective, multicentre PANTS cohort study
This is the final version. Available from Elsevier via the DOI in this record.âŻBackground We sought to report the effectiveness of infliximab and adalimumab over the first 3 years of treatment
and to define the factors that predict anti-TNF treatment failure and the strategies that prevent or mitigate loss of
response.
Methods Personalised Anti-TNF therapy in Crohnâs disease (PANTS) is a UK-wide, multicentre, prospective
observational cohort study reporting the rates of effectiveness of infliximab and adalimumab in anti-TNF-naive patients
with active luminal Crohnâs disease aged 6 years and older. At the end of the first year, sites were invited to enrol
participants still receiving study drug into the 2-year PANTS-extension study. We estimated rates of remission across
the whole cohort at the end of years 1, 2, and 3 of the study using a modified survival technique with permutation
testing. Multivariable regression and survival analyses were used to identify factors associated with loss of response
in patients who had initially responded to anti-TNF therapy and with immunogenicity. Loss of response was defined
in patients who initially responded to anti-TNF therapy at the end of induction and who subsequently developed
symptomatic activity that warranted an escalation of steroid, immunomodulatory, or anti-TNF therapy, resectional
surgery, or exit from study due to treatment failure. This study was registered with ClinicalTrials.gov, NCT03088449,
and is now complete.
Findings Between March 19, 2014, and Sept 21, 2017, 389 (41%) of 955 patients treated with infliximab and
209 (32%) of 655 treated with adalimumab in the PANTS study entered the PANTS-extension study (median age
32·5 years [IQR 22·1â46·8], 307 [51%] of 598 were female, and 291 [49%] were male). The estimated proportion of
patients in remission at the end of years 1, 2, and 3 were, for infliximab 40·2% (95% CI 36·7â43·7),
34·4% (29·9â39·0), and 34·7% (29·8â39·5), and for adalimumab 35·9% (95% CI 31·2â40·5), 32·9% (26·8â39·2),
and 28·9% (21·9â36·3), respectively. Optimal drug concentrations at week 14 to predict remission at any later
timepoints were 6·1â10·0 mg/L for infliximab and 10·1â12·0 mg/L for adalimumab. After excluding patients who
had primary non-response, the estimated proportions of patients who had loss of response by years 1, 2, and 3
were, for infliximab 34·4% (95% CI 30·4â38·2), 54·5% (49·4â59·0), and 60·0% (54·1â65·2), and for adalimumab
32·1% (26·7â37·1), 47·2% (40·2â53·4), and 68·4% (50·9â79·7), respectively. In multivariable analysis, loss of
response at year 2 and 3 for patients treated with infliximab and adalimumab was predicted by low anti-TNF drug
concentrations at week 14 (infliximab: hazard ratio [HR] for each ten-fold increase in drug concentration 0·45
[95% CI 0·30â0·67], adalimumab: 0·39 [0·22â0·70]). For patients treated with infliximab, loss of response was
also associated with female sex (vs male sex; HR 1·47 [95% CI 1·11â1·95]), obesity (vs not obese 1·62 [1·08â2·42]),
baseline white cell count (1·06 [1·02â1·11) per 1 Ă 10âč increase in cells per L), and thiopurine dose quartile. Among
patients treated with adalimumab, carriage of the HLA-DQA1*05 risk variant was associated with loss of response
(HR 1·95 [95% CI 1·17â3·25]). By the end of year 3, the estimated proportion of patients who developed anti-drug
antibodies associated with undetectable drug concentrations was 44·0% (95% CI 38·1â49·4) among patients
treated with infliximab and 20·3% (13·8â26·2) among those treated with adalimumab. The development of antidrug antibodies associated with undetectable drug concentrations was significantly associated with treatment
without concomitant immunomodulator use for both groups (HR for immunomodulator use: infliximab 0·40
[95% CI 0·31â0·52], adalimumab 0·42 [95% CI 0·24â0·75]), and with carriage of HLA-DQA1*05 risk variant for
infliximab (HR for carriage of risk variant: infliximab 1·46 [1·13â1·88]) but not for adalimumab (HR 1·60
[0·92â2·77]). Concomitant use of an immunomodulator before or on the day of starting infliximab was associated
with increased time without the development of anti-drug antibodies associated with undetectable drug
concentrations compared with use of infliximab alone (HR 2·87 [95% CI 2·20â3·74]) or introduction of an
immunomodulator after anti-TNF initiation (1·70 [1·11â2·59]). In years 2 and 3, 16 (4%) of 389 patients treated
with infliximab and 11 (5%) of 209 treated with adalimumab had adverse events leading to treatment withdrawal.
Nine (2%) patients treated with infliximab and two (1%) of those treated with adalimumab had serious infections
in years 2 and 3.
Interpretation Only around a third of patients with active luminal Crohnâs disease treated with an anti-TNF drug were
in remission at the end of 3 years of treatment. Low drug concentrations at the end of the induction period predict
loss of response by year 3 of treatment, suggesting higher drug concentrations during the first year of treatment,
particularly during induction, might lead to better long-term outcomes. Anti-drug antibodies associated with
undetectable drug concentrations of infliximab, but not adalimumab, can be predicted by carriage of HLA-DQA1*05
and mitigated by concomitant immunomodulator use for both drugs.Guts UKCrohnâs and Colitis UKCure Crohnâs ColitisAbbVieMerck Sharp and DohmeNapp PharmaceuticalsPfizerCelltrion Healthcar
International Consensus Statement on Rhinology and Allergy: Rhinosinusitis
Background: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICARâRS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICARâRSâ2021 as well as updates to the original 140 topics. This executive summary consolidates the evidenceâbased findings of the document. Methods: ICARâRS presents over 180 topics in the forms of evidenceâbased reviews with recommendations (EBRRs), evidenceâbased reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary. Results: ICARâRSâ2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidenceâbased management algorithm is provided. Conclusion: This ICARâRSâ2021 executive summary provides a compilation of the evidenceâbased recommendations for medical and surgical treatment of the most common forms of RS
Ciliary beat pattern analysis below 37°C may risk PCD misdiagnosis
Primary Ciliary Dyskinesia (PCD) is a rare inherited multi-genic disorder of mucociliary function. Patients with indicative clinical profiles referred to the UK specialist PCD service receive a diagnosis based on multiple factors. These include high-speed video microscopy (HSVM) analysis of ciliary beat pattern (CBP) and ciliary beat frequency (CBF) at 37°C (for in vivo modelling). In PCD, ciliary axonemal defects generate abnormal CBP with/without abnormal CBF. Corresponding and predominant ultrastructural defects are determined by TEM, except in atypical cases. We report an atypical PCD patient (8 months old) with respiratory and nasal symptoms since birth, situs inversus and serous otitis media. HSVM confirmed abnormal and hyperfrequent ciliary function at 37°C on four occasions, but normal ciliary ultrastructure. On two occasions CBP and CBF (mean ±SD) were assessed at 37oC and room temperature (21-24°C). At 37°C CBF was hyperfrequent (34.4 Hz ±13.5 n=11; 26.3 Hz ±3.4 n=6) and CBP consistently abnormal with interrupted, short range, dyskinetic motility. However at room temperature the same cilia reverted to CBF (15.2 Hz ±4.5 n=2; 12.6 Hz ±0.8 n=6) within our normal range (11-20 Hz) with improved ciliary coordination and range of movement, suggesting a PCD variant with temperature sensitive CBP. Recent research suggests that healthy human epithelium maintains a normal CBP at temperatures as low as 2°C, and low temperature ciliary analysis may diagnostically replace HSVM. However, in light of our case study we conclude that temperature sensitive variants of PCD may exist and CBP analysis below 37°C without HSVM may risk PCD misdiagnosis
High-resolution 3D imaging of osteocytes and computational modelling in mechanobiology: insights on bone development, ageing, health and disease
Osteocytes are involved in mechanosensation and mechanotransduction in bone and hence, are key to bone adaptation in response to development, ageing and disease. Thus, detailed knowledge of the three-dimensional (3D) structure of the osteocyte network (ON) and the surrounding lacuno-canalicular network (LCN) is essential. Enhanced understanding of the ON&LCN will contribute to a better understanding of bone mechanics on cellular and sub-cellular scales, for instance through improved computational models of bone mechanotransduction. Until now, the location of the ON within the hard bone matrix and the sub-”m dimensions of the ON&LCN have posed significant challenges for 3D imaging. This review identifies relevant microstructural phenotypes of the ON&LCN in health and disease and summarises how light microscopy, electron microscopy and X-ray imaging techniques have been used in studies of osteocyte anatomy, pathology and mechanobiology to date. In this review, we assess the requirements for ON&LCN imaging and examine the state of the art in the fields of imaging and computational modelling as well as recent advances in high-resolution 3D imaging. Suggestions for future investigations using volume electron microscopy are indicated and we present new data on the ON&LCN using serial block-face scanning electron microscopy. A correlative approach using these high-resolution 3D imaging techniques in conjunction with in silico modelling in bone mechanobiology will increase understanding of osteocyte function and, ultimately, lead to improved pathways for diagnosis and treatment of bone diseases such as osteoporosis
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