Consensus guidelines of ECCO/ESPGHAN on the medical management of pediatric Crohn's disease

Children and adolescents with Crohn's disease (CD) present often with a more complicated disease course compared to adult patients. In addition, the potential impact of CD on growth, pubertal and emotional development of patients underlines the need for a specific management strategy of pediatric-onset CD. To develop the first evidenced based and consensus driven guidelines for pediatric-onset CD an expert panel of 33 IBD specialists was formed after an open call within the European Crohn's and Colitis Organisation and the European Society of Pediatric Gastroenterolog, Hepatology and Nutrition. The aim was to base on a thorough review of existing evidence a state of the art guidance on the medical treatment and long term management of children and adolescents with CD, with individualized treatment algorithms based on a benefit-risk analysis according to different clinical scenarios. In children and adolescents who did not have finished their growth, exclusive enteral nutrition (EEN) is the induction therapy of first choice due to its excellent safety profile, preferable over corticosteroids, which are equipotential to induce remission. The majority of patients with pediatric-onset CD require immunomodulator based maintenance therapy. The experts discuss several factors potentially predictive for poor disease outcome (such as severe perianal fistulizing disease, severe stricturing/penetrating disease, severe growth retardation, panenteric disease, persistent severe disease despite adequate induction therapy), which may incite to an anti-TNF-based top down approach. These guidelines are intended to give practical (whenever possible evidence-based) answers to (pediatric) gastroenterologists who take care of children and adolescents with CD; they are not meant to be a rule or legal standard, since many different clinical scenario exist requiring treatment strategies not covered by or different from these guidelines.

The prevalence of pelvic floor disorders and their relationship to gender, age, parity and mode of delivery

OBJECTIVE

To define the prevalence of pelvic floor disorders in a non-institutionalised community and to determine the relationship to gender, age, parity and mode of delivery.

DESIGN

A representative population survey using the 1998 South Australian Health Omnibus Survey.

SAMPLE

Random selection of 4400 households; 3010 interviews were conducted in the respondents' homes by trained female interviewers. This cross sectional survey included men and women aged 15-97 years.

RESULTS

The prevalence of all types of self-reported urinary incontinence in men was 4.4% and in women was 35.3% (P<0.001). Urinary incontinence was more commonly reported in nulliparous women than men and increased after pregnancy according to parity and age. The highest prevalence (51.9%) was reported in women aged 70-74 years. The prevalence of flatus and faecal incontinence was 6.8% and 2.3% in men and 10.9% and 3.5% in women, respectively. Pregnancy (> 20 weeks), regardless of the mode of delivery, greatly increased the prevalence of major pelvic floor dysfunction, defined as any type of incontinence, symptoms of prolapse or previous pelvic floor surgery. Multivariate logistic regression showed that, compared with nulliparity, pelvic floor dysfunction was significantly associated with caesarean section (OR 2.5, 95% CI 1.5-4.3), spontaneous vaginal delivery (OR 3.4, 95% CI 2.4-4.9) and at least one instrumental delivery (OR 4.3, 95% CI 2.8-6.6). The difference between caesarean and instrumental delivery was significant (P<0.03) but was not for caesarean and spontaneous delivery. Other associations with pelvic floor morbidity were age, body mass index, coughing, osteoporosis, arthritis and reduced quality of life scores. Symptoms of haemorrhoids also increased with age and parity and were reported in 19.9% of men and 30.2% of women.

CONCLUSION

Pelvic floor disorders are very common and are strongly associated with female gender, ageing, pregnancy, parity and instrumental delivery. Caesarean delivery is not associated with a significant reduction in long term pelvic floor morbidity compared with spontaneous vaginal delivery.

Prevalence and cost of alternative medicine in Australia

BACKGROUND

To determine the prevalence and cost of alternative medicines and alternative practitioner use in an Australian population.

METHODS

We conducted a representative population survey of persons aged 15 or older living in South Australia, which required 3004 personal interviews. We assessed the rates of use and types of alternative medicine and therapists used by this population in 1993, and correlations with other demographic and medical variables.

FINDINGS

The overall use of at least one non-medically prescribed alternative medicine (excluding calcium, iron and prescribed vitamins) was 48.5%. The users were more likely to be perimenopausal females, better educated, have a higher alcohol intake, be of normal weight and more likely to be employed than non-users. 20.3% of respondents had visited at least one alternative practitioner, most commonly chiropractors (15%). The users of alternative practitioners were more likely to be younger, live in the country and be overweight. Women were more likely to consult naturopaths, iridiologists, and reflexologists than men.

INTERPRETATION

Extrapolation of the costs to the Australian population gives a natural expenditure in 1993, for alternative medicines, of $621 million (Australian dollars) and for alternative therapists of $AU309 million per annum. This compares to the $AU360 million of patient contributions for all classes of pharmaceutical drugs purchased in Australia in 1992/93. The public health and economic ramifications of these huge costs are questioned in view of the paucity of sound safety and efficacy data for many of the therapies and products of the alternative medicine industry.

The Postpartum Bonding Questionnaire: a validation

This is a validation of a self-rating questionnaire designed to detect disorders of the mother-infant relationship. 125 subjects filled in the questionnaire, and were also interviewed using the 5(th) Edition of the Birmingham Interview for Maternal Mental Health. On the basis of these interviews and the case records, we made consensus diagnoses of various forms and degrees of mother infant relationship disorder, according to criteria published in this paper. We calculated specificity, sensitivity and positive predictive value of the four scale scores generated by the questionnaire. Scale 1 (a general factor) had a sensitivity of 0.82 for all mother-infant relationship disorders. Scale 2 (rejection and pathological anger) had a sensitivity of 0.88 for rejection of the infant, but only 0.67 for severe anger. The performance of scale 3 (infant-focused anxiety) was unsatisfactory. Scale 4 (incipient abuse) selected only a few mothers, but was of some value in identifying those at high risk of child abuse. Revision of the thresholds can improve sensitivity, especially of scale 2, where a cut-off point of 12 = normal, 13 = high better identifies mothers with threatened rejection. These new cut-off points would need validation in another sample.

Cooperative dimerization of paired class homeo domains on DNA

Homeo domain-containing proteins mediate many transcriptional processes in eukaryotes. Because nearly all animal homeo proteins are believed to bind to short, highly related DNA sequences, the basis for their high specificity of action is not understood. We show that cooperative dimerization on palindromic DNA sequences can provide increased specificity to one of the three major classes of homeo domains, the Paired/Pax class. The 60-amino-acid homeo domains from this class contain sufficient information to bind cooperatively as homo- and heterodimers to palindromic DNA sequences; that is, the binding of one homeo domain molecule can increase the affinity of a second molecule by up to 300-fold. Different members of the Paired (Prd) class of homeo domains prefer different spacings between half-sites, as determined by the ninth amino acid residue of the recognition helix. In addition, this residue determines the identity of the base pairs at the center of the palindromic sites, as well as the magnitude of the cooperative interaction. The cooperative dimerization of homeo domains in the Prd class distinguishes them from other classes, whereas binding-site configuration and sequence specificity allow for distinctions within this class.

Abnormal in vivo metabolism of apolipoprotein E4 in humans

Apolipoprotein E (apoE) is important in modulating the catabolism of remnants of triglyceride-rich lipoprotein particles. It is a polymorphic protein with the three common alleles coding for apoE2, apoE3, and apoE4. ApoE3 is considered the normal isoform, while apoE4 is associated both with hypercholesterolemia and type V hyperlipoproteinemia. We quantitated the kinetics of metabolism of apoE4 in 19 normolipidemic apoE3 homozygotes and 1 normolipidemic apoE4 homozygote, and compared this with the metabolism of apoE3 in 12 normolipidemic apoE3 homozygotes. In the apoE3 homozygous subjects, apoE4 was catabolized twice as fast as apoE3, with a mean plasma residence time of 0.37 +/- 0.01 d (+/- SEM) and 0.73 +/- 0.05 (P less than 0.001), respectively. When plasma was fractionated into the lipoprotein subclasses, the greatest amount of labeled apoE4 was present on very low density lipoproteins, while the largest fraction of labeled apoE3 was associated with high density lipoproteins. The plasma apoE concentration was decreased in an apoE4 homozygote compared with the apoE3 homozygotes (3.11 mg/dl vs. 4.83 +/- 0.35 mg/dl). The reduced apoE4 concentration was entirely due to a decreased apoE4 residence time in the apoE4 homozygote (0.36 d vs. 0.73 +/- 0.05 d for apoE3 in apoE3 homozygotes). These results indicate that apoE4 is kinetically different than apoE3, and suggest that the presence of apoE4 in hypercholesterolemic and type V hyperlipoproteinemic individuals may play an important pathophysiological role in the development of these dyslipoproteinemias.

Discovery of CGS 27023A, a non-peptidic, potent, and orally active stromelysin inhibitor that blocks cartilage degradation in rabbits

Structure-activity relationships of a lead hydroxamic acid inhibitor of recombinant human stromelysin were systematically defined by taking advantage of a concise synthesis that allowed diverse functionality to be explored at each position in a template. An ex vivo rat model and an in vivo rabbit model of stromelysin-induced cartilage degradation were used to further optimize these analogs for oral activity and duration of action. The culmination of these modifications resulted in CGS 27023A, a potent, orally active stromelysin inhibitor that blocks the erosion of cartilage matrix.

Inflammation and angiogenesis in osteoarthritis

OBJECTIVE

To quantify the relationship between inflammation and angiogenesis in synovial tissue from patients with osteoarthritis (OA).

METHODS

Hematoxylin and eosin staining and histologic grading for inflammation were performed for 104 patients who met the American College of Rheumatology criteria for OA and had undergone total joint replacement or arthroscopy. A purposive sample of synovial specimens obtained from 70 patients was used for further analysis. Vascular endothelium, endothelial cell (EC) proliferating nuclei, macrophages, and vascular endothelial growth factor (VEGF) were detected by immunohistochemical analysis. Angiogenesis (EC proliferation, EC fractional area), macrophage fractional area, and VEGF immunoreactivity were measured using computer-assisted image analysis. Double immunofluorescence histochemical analysis was used to determine the cellular localization of VEGF. Radiographic scores for joint space narrowing and osteophyte formation in the knee were also assessed.

RESULTS

Synovial tissue samples from 32 (31%) of 104 patients with OA showed severe inflammation; thickened intimal lining and associated lymphoid aggregates were often observed. The EC fractional area, EC proliferation, and VEGF immunoreactivity all increased with increasing histologic inflammation grade and increasing macrophage fractional area. In the synovial intimal lining, VEGF immunoreactivity was localized to macrophages and increased with increasing EC fractional area and angiogenesis. No inflammation or angiogenic indices were significantly correlated with radiographic scores.

CONCLUSION

Inflammation and angiogenesis in the synovium are associated with OA. The angiogenic growth factor VEGF generated by the inflamed synovium may promote angiogenesis, thereby contributing to inflammation in OA.

Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

TAP- and tapasin-dependent HLA-E surface expression correlates with the binding of an MHC class I leader peptide

BACKGROUND

The human major histocompatibility complex (MHC) class lb molecule HLA-E is transcribed in most tissues but little is known about its localisation within the cell. We have recently shown that HLA-E binds signal-sequence-derived peptides from human MHC class I molecules in vitro.

RESULTS

Using a newly characterised antibody recognising HLA-E, we show that HLA-E is expressed at the cell surface. We demonstrate that HLA-E surface expression is correlated with the presence of MHC class I molecules which provide suitable leader sequence peptides capable of binding to HLA-E. Further studies on the interaction of HLA-E with molecules in the endoplasmic reticulum revealed that HLA-E associates with the transporter associated with antigen processing (TAP) and calreticulin, and that HLA-E expression is TAP-dependent and tapasin-dependent. In addition, HLA-E dissociates from TAP upon binding of MHC class I leader sequence peptides.

CONCLUSION

These experiments establish that surface expression of HLA-E is regulated by the binding of a restricted pool of peptides from the leader sequence of MHC class I molecules. The correlation between HLA-E and MHC class I surface expression might be relevant to the function of HLA-E. Our results also show that, although these HLA-E binding peptides are derived from signal sequences, they may be released back into the cytosol and subsequently translocated by the TAP complex and loaded onto HLA-E molecules.

Choice making to promote adaptive behavior for students with emotional and behavioral challenges

Two analyses investigated the effects of choice making on the responding of elementary school students with emotional and behavioral challenges. In the first analysis, 2 participants were given choices from menus of academic tasks, all of which were pertinent to their educational objectives in English and spelling, respectively. Reversal designs showed that the choice-making conditions increased task engagement and reduced disruptive behavior for both students. An additional analysis was performed with a 3rd student in an effort to further distinguish the effects of choice making from preference. In this study, one of the no-choice phases was yoked to a previous choice-making condition. This analysis demonstrated that the choice-making condition was superior to baseline and yoked control phases as determined by levels of task engagement and disruptive behavior. The findings of the two analyses contribute information relevant to students with emotional and behavioral disorders, and to a growing literature on the desirable effects of choice making for students with disabilities and challenging behaviors.

Mutations in a new gene in Ellis-van Creveld syndrome and Weyers acrodental dysostosis

Ellis-van Creveld syndrome (EvC, MIM 225500) is an autosomal recessive skeletal dysplasia characterized by short limbs, short ribs, postaxial polydactyly and dysplastic nails and teeth. Congenital cardiac defects, most commonly a defect of primary atrial septation producing a common atrium, occur in 60% of affected individuals. The disease was mapped to chromosome 4p16 in nine Amish subpedigrees and single pedigrees from Mexico, Ecuador and Brazil. Weyers acrodental dysostosis (MIM 193530), an autosomal dominant disorder with a similar but milder phenotype, has been mapped in a single pedigree to an area including the EvC critical region. We have identified a new gene (EVC), encoding a 992-amino-acid protein, that is mutated in individuals with EvC. We identified a splice-donor change in an Amish pedigree and six truncating mutations and a single amino acid deletion in seven pedigrees. The heterozygous carriers of these mutations did not manifest features of EvC. We found two heterozygous missense mutations associated with a phenotype, one in a man with Weyers acrodental dysostosis and another in a father and his daughter, who both have the heart defect characteristic of EvC and polydactyly, but not short stature. We suggest that EvC and Weyers acrodental dysostosis are allelic conditions.

Systematic reviews of sublingual immunotherapy (SLIT)

Allergic rhinitis is common worldwide, with significant morbidity and impact on quality of life. In patients who don't respond adequately to anti-allergic drugs. Subcutaneous allergen immunotherapy is effective although requires specialist administration. Sublingual immunotherapy may represent an effective and safer alternative. This Cochrane systematic review is an update of one published in 2003. We searched Cochrane ENT Group Trials Register, Central, PubMed, EMBASE, CINAHL, Web of Science, Biosis Previews, Cambridge Scientific Abstarcts, mRCT and additional sources. We included randomised, double-blind, placebo- controlled trials of sublingual immunotherapy in adults and children. Two authors selected studies and assessed them for quality. Data were put into RevMan 5.0 for a statistical analysis. We used standardised mean difference (SMD), with a random effect model to combine data. Sixty studies were included, with 49 suitable for meta-analysis. We found significant reductions in symptoms (SMD -0.49; 95%CI (-0.64 to -0.34, P < 0.00001)) and medication requirements (SMD -0.32; 95%CI (-0.43 to -0.21, P < 0.00001)) compared with placebo. None of the trials reported severe systemic reactions, anaphylaxis or use of Adrenaline. This updated review reinforces the conclusion of the original 2003 Cochrane Review that sublingual immunotherapy is effective for allergic rhinitis and appears a safe route of administration.

Hepatic lesion detection: comparison of MR imaging after the administration of superparamagnetic iron oxide with dual-phase CT by using alternative-free response receiver operating characteristic analysis

PURPOSE

To compare the performance of magnetic resonance (MR) imaging after the administration of superparamagnetic iron oxide (SPIO) and dual-phase computed tomography (CT) in the depiction of liver metastases.

MATERIALS AND METHODS

Fifty-one hepatic resection candidates with known colorectal metastases were examined. MR imaging comprised fast spin-echo (SE) T2-weighted imaging, T1-weighted gradient-echo (GRE) fast low-angle shot imaging before SPIO enhancement, dual-echo SE imaging, T2-weighted fast low-angle shot imaging, and T1-weighted GRE imaging after SPIO enhancement. CT was performed with 8-mm collimation and 1:1 pitch; imaging commenced 20 seconds and 65-70 seconds after injection of 150 mL of contrast medium. All images were reviewed independently by four blinded observers. The alternative-free response receiver operating characteristic (ROC) method was used to analyze the results, which were correlated with findings from surgery, intraoperative ultrasonography, and histopathologic studies in 31 patients and with consensus review together with all other imaging and clinical follow-up in 20 patients. Sensitivities were also calculated.

RESULTS

The mean sensitivity of MR was significantly higher than that of CT (p < .02): 79.8% for MR and 75.3% for CT for all lesions, and 80.6% for MR and 73.5% for CT for malignant lesions. The mean areas under the alternative-free response ROC curves were 0.83 for MR and 0.78 for CT (difference not significant).

CONCLUSION

SPIO-enhanced MR imaging was more sensitive than dual-phase CT in the depiction of colorectal metastases.

Cassini Observes the Active South Pole of Enceladus

Cassini has identified a geologically active province at the south pole of Saturn's moon Enceladus. In images acquired by the Imaging Science Subsystem (ISS), this region is circumscribed by a chain of folded ridges and troughs at approximately 55 degrees S latitude. The terrain southward of this boundary is distinguished by its albedo and color contrasts, elevated temperatures, extreme geologic youth, and narrow tectonic rifts that exhibit coarse-grained ice and coincide with the hottest temperatures measured in the region. Jets of fine icy particles that supply Saturn's E ring emanate from this province, carried aloft by water vapor probably venting from subsurface reservoirs of liquid water. The shape of Enceladus suggests a possible intense heating epoch in the past by capture into a 1:4 secondary spin/orbit resonance.

Conformational transitions in model silk peptides

Protein structural transitions and beta-sheet formation are a common problem both in vivo and in vitro and are of critical relevance in disparate areas such as protein processing and beta-amyloid and prion behavior. Silks provide a "databank" of well-characterized polymorphic sequences, acting as a window onto structural transitions. Peptides with conformationally polymorphic silk-like sequences, expected to exhibit an intractable beta-sheet form, were characterized using Fourier transform infrared spectroscopy, circular dichroism, and electron diffraction. Polymorphs resembling the silk I, silk II (beta-sheet), and silk III (threefold polyglycine II-like helix) crystal structures were identified for the peptide fibroin C (GAGAGS repetitive sequence). Two peptides based on silk amorphous sequences, fibroin A (GAGAGY) and fibroin V (GDVGGAGATGGS), crystallized as silk I under most conditions. Methanol treatment of fibroin A resulted in a gradual transition from silk I to silk II, with an intermediate state involving a high proportion of beta-turns. Attenuated total reflectance Fourier transform infrared spectroscopy has been used to observe conformational changes as the peptides adsorb from solution onto a hydrophobic surface. Fibroin C has a beta-strand structure in solution but adopts a silk I-like structure upon adsorption, which when dried on the ZnSe crystal contains silk III crystallites.

Conotruncal anomaly face syndrome is associated with a deletion within chromosome 22q11

The conotruncal anomaly face syndrome was described in a Japanese publication in 1976 and comprises dysmorphic facial appearance and outflow tract defects of the heart. The authors subsequently noted similarities to Shprintzen syndrome and DiGeorge syndrome. Chromosome analysis in five cases did not show a deletion at high resolution, but fluorescent in situ hybridisation using probe DO832 showed a deletion within chromosome 22q11 in all cases.

Angiogenesis in the synovium and at the osteochondral junction in osteoarthritis

OBJECTIVES

We hypothesised that osteochondral and synovial angiogenesis in osteoarthritis (OA) are independent processes. We investigated whether indices of osteochondral and synovial angiogenesis display different relationships with synovitis, disease severity and chondrocalcinosis in patients with OA.

DESIGN

Synovium and medial tibial plateaux were obtained from 62 patients undergoing total knee joint replacement for OA (18 [29%] had chondrocalcinosis) and from 31 recently deceased people with no evidence of joint pathology post-mortem (PM). Vascular endothelium, proliferating endothelial cells (ECs) and macrophages were quantified by immunohistochemistry for CD34, CD31/Ki67 and CD14, respectively. Grades were assigned for radiographic and histological OA disease severity, clinical disease activity and histological synovitis (based on cellular content of the synovium).

RESULTS

Blood vessels breached the tidemark in 60% of patients with OA and 20% of PM controls. Osteochondral vascular density increased with increasing cartilage severity and clinical disease activity scores, but not with synovitis. Synovial EC proliferation, inflammation and macrophage infiltration were higher in OA than in PM controls. Synovial angiogenesis indices increased with increasing histological synovitis, but were not related to osteochondral vascular density or other indices of OA disease severity. OA changes were more severe in patients with concurrent chondrocalcinosis. Chondrocalcinosis was not associated with increased angiogenesis or histological synovitis beyond that seen in OA alone.

CONCLUSION

Osteochondral and synovial angiogenesis appear to be independent processes. Osteochondral vascularity is associated with the severity of OA cartilage changes and clinical disease activity, whereas synovial angiogenesis is associated with histological synovitis. Modulation of osteochondral and synovial angiogenesis may differentially affect OA disease.

Genetic dissection of autoimmune type I diabetes in the BB rat

The BB rat is among the best models of insulin-dependent diabetes mellitus--with onset and pathogenesis closely resembling the human disease. One unusual feature is a severe T-cell lymphopenia, which appears to be inherited as a recessive trait controlled by a single gene, Lyp. Based on genetic analysis of several crosses, we show that development of diabetes involves at least three genes: Lyp, which is tightly linked to the neuropeptide Y (Npy) gene on chromosome 4, a gene linked to the major histocompatibility complex (MHC) on chromosome 20, and a third unmapped gene for which the Fischer rat strain carries an allele conferring resistance.

Prevention of nitroimidazole resistance in Campylobacter pylori by coadministration of colloidal bismuth subcitrate: clinical and in vitro studies

One hundred patients with duodenal ulceration and Campylobacter pylori in their stomach were entered into a double blind placebo controlled prospective study. Treatment schedules were cimetidine and placebo, or cimetidine and tinidazole, or colloidal bismuth subcitrate (CBS) and placebo, or CBS and tinidazole. Seventeen per cent of isolates of C pylori obtained at the first endoscopy were resistant to tinidazole and 70% of the second isolates from patients given cimetidine and tinidazole became tinidazole resistant. Suspensions of nitroimidazole sensitive cultures of C pylori showed that three of 22 isolates had a nitroimidazole resistant subpopulation. In patients who healed and remained free of C pylori after treatment ulcers recurred less often than in patients who healed but retained C pylori (23% v 73% over 12 months, p less than 0.001).

Reasons for modification and discontinuation of antiretrovirals: results from a single treatment centre

OBJECTIVE

To describe the reasons for, and factors associated with, modification and discontinuation of highly active antiretroviral therapy (HAART) regimens at a single clinic.

SUBJECTS

A total of 556 patients who started HAART at the Royal Free Hospital were included in analyses. Modification was defined as stopping or switching any antiretrovirals in the regimen, whereas discontinuation was defined as the simultaneous stopping of all antiretrovirals included in the initial regimen. Reasons were classified as immunological/virological failure (IVF) and toxicities and patient choice/poor compliance (TPC).

RESULTS

The median CD4 count at starting HAART was 171 x 10(6) cells/l and viral load 5.07 log copies/ml. During a median follow-up of 14.2 months, 247 patients (44.4%) modified their HAART regimen, 72 due to IVF (29.1%) and 159 due to TPC (64.4%) and a total of 148 patients (26.6%) discontinued HAART. Older patients were less likely to modify HAART [relative hazard (RH), 0.73 per 10 years; P = 0.0008], as were previously treatment-naive patients (RH, 0.65; P = 0.0050), those in a clinical trial (RH, 0.64; P = 0.027) and those who started nelfinavir (RH, 0.57; P = 0.035). Patients who started with four or more drugs (RH, 2.21, P < 0.0001), who included ritonavir in the initial regimen (RH, 1.41; P = 0.035) or who had higher viral loads during follow-up (RH per log increase, 1.51; P < 0.0001) were more likely to modify HAART.

CONCLUSIONS

There was a high rate of modification and discontinuation of HAART regimens in the first 12 months, particularly due to toxicities, patient choice or poor compliance.

The health-related quality-of-life of never smokers, ex-smokers, and light, moderate, and heavy smokers

BACKGROUND

Health related quality-of-life is recognized as an important health outcome measure; how ever, it may also have a significant application in smoking reduction and cessation programs.

METHODS

Representative population data (n = 3010) was used to compare the quality-of-life status of differ ent smoking categories with never smokers.

RESULTS

Statistically significant differences in mean quality-of-life scores, as measured by the SF-36 health status questionnaire, were observed between never smokers, as the reference group, ex-smokers, all smokers, and light, moderate, and heavy smokers. Heavy smokers also scored significantly lower than both other groups of smokers, scoring as low as the 29th percentile of the population on the general health dimension and lower than the 36th percentile of the population on all the mental health dimensions.

CONCLUSIONS

The design of public health smoking cessation programs should consider the varying characteristics of different segments of the smoking population. The advantages of improved quality-of-life may strengthen the argument for encouraging heavier smokers to become light smokers as a precursor to total cessation.

iPTF16geu: A multiply imaged, gravitationally lensed type Ia supernova

We report the discovery of a multiply imaged, gravitationally lensed type Ia supernova, iPTF16geu (SN 2016geu), at redshift z = 0.409. This phenomenon was identified because the light from the stellar explosion was magnified more than 50 times by the curvature of space around matter in an intervening galaxy. We used high-spatial-resolution observations to resolve four images of the lensed supernova, approximately 0.3 arc seconds from the center of the foreground galaxy. The observations probe a physical scale of ~1 kiloparsec, smaller than is typical in other studies of extragalactic gravitational lensing. The large magnification and symmetric image configuration imply close alignment between the lines of sight to the supernova and to the lens. The relative magnifications of the four images provide evidence for substructures in the lensing galaxy.

Elasticity of the red cell membrane and its relation to hemolytic disorders: an optical tweezers study

We have used optical tweezers to study the elasticity of red cell membranes; force was applied to a bead attached to a permeabilized spherical ghost and the force-extension relation was obtained from the response of a second bead bound at a diametrically opposite position. Interruption of the skeletal network by dissociation of spectrin tetramers or extraction of the actin junctions engendered a fourfold reduction in stiffness at low applied force, but only a twofold change at larger extensions. Proteolytic scission of the ankyrin, which links the membrane skeleton to the integral membrane protein, band 3, induced a similar effect. The modified, unlike the native membranes, showed plastic relaxation under a prolonged stretch. Flaccid giant liposomes showed no measurable elasticity. Our observations indicate that the elastic character is at least as much a consequence of the attachment of spectrin as of a continuous membrane-bound network, and they offer a rationale for formation of elliptocytes in genetic conditions associated with membrane-skeletal perturbations. The theory of Parker and Winlove for elastic deformation of axisymmetric shells (accompanying paper) allows us to determine the function BH(2) for the spherical saponin-permeabilized ghost membranes (where B is the bending modulus and H the shear modulus); taking the literature value of 2 x 10(-19) Nm for B, H then emerges as 2 x 10(-6) Nm(-1). This is an order of magnitude higher than the value reported for intact cells from micropipette aspiration. Reasons for the difference are discussed.