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Summary: Background: Pemphigus is a group of rare life‐threatening mucocutaneous autoimmune diseases, presenting mainly as two subtypes: pemphigus vulgaris (PV) and pemphigus foliaceus (PF). Inherited predispositions to pemphigus have long been speculated but they remain poorly understood. Objectives: To identify common and specific nongenetic and genetic factors associated with pemphigus and its subtypes in the Chinese population. Methods: A genome‐wide association study (GWAS) was performed in 496 unrelated patients with pemphigus (including 365 with PV and 104 with PF) and 1105 controls without pemphigus. Results: A sex preference was observed only in PV (57·5% female) and not in PF (47·1% female). For male patients only, the mean age at diagnosis was significantly lower for PV than for PF (P < 0·001). The strongest associated single‐nucleotide polymorphisms are in the human leucocyte antigen (HLA) region: rs70993900 (PV; P = 1·5 × 10−45) and rs9469220 (PF; P = 1·1 × 10−8). HLA‐DQB1*05:03 ranks at the top (P = 4·7 × 10−40; odds ratio 12·4) in both subtypes, with significantly different risk allele frequency (RAFPV = 34·2% vs. RAFPF = 18·8% vs. RAFcontrol = 4·4%), whereas HLA‐DRB1*14:01 and HLA‐DRB1*04:06 are PV specific. HLA‐DQB1*03:03 and HLA‐DQB1*03:02 show significant subtype specificity in opposite directions. All of these associations were validated in the replication series with 147 cases of pemphigus and 604 controls. Multiple novel non‐HLA susceptibility loci were also identified in the GWAS. Conclusions: This study represents the largest GWAS on pemphigus in the Chinese population published to date, and has allowed us to identify HLA haplotypes significantly shared between or specific to the two main subtypes of pemphigus. What's already known about this topic? Pemphigus is a group of autoimmune mucocutaneous diseases.It has multiple subtypes associated with certain human leucocyte antigen (HLA) haplotypes in an ethnicity‐specific manner. What does this study add? This is the largest genome‐wide association study published on pemphigus to date.We identified, for the first time, more than 100 single‐nucleotide polymorphisms (SNPs; six independent) at the HLA locus, with associations reaching genome‐wide significance.Some of these SNPs are strongly associated with specific subtypes of pemphigus. What is the translational message? The identified new haplotypes can potentially serve as genetic markers to improve investigation of the epidemiology and pathogenesis of pemphigus and its specific subtypes. Linked Comment:Geller. Br J Dermatol 2019; 180:713–714. Respond to this article [ABSTRACT FROM AUTHOR]

Asthma and allergic rhinitis (AR) frequently coexist, but have usually been studied separately in health economic analyses.To determine the incremental effect of documented AR on health care resource use in adults with asthma.A retrospective cohort study using data from a UK general practice database for the period 1998–2001 enrolled subjects 16–55 years of age, with one or more asthma-related general practitioner (GP) visits during a 12-month follow-up period. The study outcomes were asthma-related hospitalizations, GP visits, and prescription drug costs during the 12-month follow-up period for patients with and without physician-diagnosed AR.Concomitant AR was documented in 4611 (16.9%) of the total sample of 27 303 adults with asthma. Compared with those with asthma alone, patients with concomitant AR experienced more GP visits (5.2 vs. 4.2;P<0.0001) and more of them were hospitalized for asthma (0.76% vs. 0.45%;P<0.01) during the 12-month follow-up period. In multi-variable regression analyses, AR was predictive of hospitalization for asthma (odds ratio 1.52, 95% confidence interval (CI) 1.03–2.24) and was associated with an increase in the annual number of asthma-related GP visits (mean increase per patient 0.42, 95% CI 0.42–0.43) and annual asthma-related drug costs (mean increase GBP 5.1, 95% CI 5.0–5.3).Adults with asthma and documented concomitant AR experienced more asthma-related hospitalizations and GP visits, and incurred higher asthma drug costs than did adults with asthma alone. A unified treatment strategy for asthma and AR might reduce the costs of treating these conditions. [ABSTRACT FROM AUTHOR]

It is now widely known that a magnetic field, either homogeneous or inhomogeneous, depresses the growth process of protein crystals. In this report, the dissolution process of tetragonal lysozyme crystals is also confirmed to be depressed by a homogeneous magnetic field (inhomogeneity <1.5%). The dissolution process was monitored using a Mach-Zehnder interferometer. The results showed that the concentration change during the dissolution process was slowed in a magnetic field compared with that in the absence of a magnetic field. It was concluded that the diffusion coefficient of the lysozyme molecules in the solution was decreased by the magnetic field. The decrease in the diffusion coefficient may contribute to the slowed growth process. The changes in the spatial concentration distribution under a vertical temperature gradient before crystallization in the absence of a magnetic field was also studied. The concentration in the lower, colder part of the cell increased, while it decreased in the upper, hotter part, a similar phenomenon to that discovered by previous investigators in an isothermal supersaturated solution system. Aggregated domain formation is proposed to explain the concentration redistribution before crystal growth and a suspended crystal model is proposed to explain the decrease of diffusivity in a magnetic field. [ABSTRACT FROM AUTHOR]