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Viruses that affect humans, animals and plants are often dispersed and transmitted through airborne routes of infection. Due to current technological deficiencies, accurate determination of the presence of airborne viruses is challenging. This shortcoming limits our ability to evaluate the actual threat arising from inhalation or other relevant contact with aerosolized viruses. To improve our understanding of the mechanisms of airborne transmission of viruses, air sampling technologies that can detect the presence of aerosolized viruses, effectively collect them and maintain their viability, and determine their distribution in aerosol particles, are needed. The latest developments in sampling and detection methodologies for airborne viruses, their limitations, factors that can affect their performance and current research needs, are discussed in this review. Much more work is needed on the establishment of standard air sampling methods and their performance requirements. Sampling devices that can collect a wide size range of virus-containing aerosols and maintain the viability of the collected viruses are needed. Ideally, the devices would be portable and technology-enabled for on-the-spot detection and rapid identification of the viruses. Broad understanding of the airborne transmission of viruses is of seminal importance for the establishment of better infection control strategies., (© 2019 The Society for Applied Microbiology.)

Background: Bullous pemphigoid (BP) is the most common autoimmune subepidermal blistering skin disease. Two antigens have been identified as targets of circulating autoantibodies (autoAbs) - BP180 and BP230 - with BP180 being a critical transmembrane adhesion protein of basal keratinocytes of the epidermis. The noncollagenous domain 16A (NC16A) of BP180 is the immunodominant epitope in patients with BP, and anti-BP180-NC16A IgG antibodies (Abs) correlate to disease activity. Routine serological testing and follow-up of BP relies on indirect immunofluorescence (IIF) of serum Abs, commonly performed on monkey oesophagus (ME), and/or enzyme-linked immunosorbent assay (ELISA) testing on recombinantly produced fragments of BP180 and BP230 (BP180-NC16A, BP230-C/N)., Objectives: To determine if NC16A epitopes are well represented on ME substrate., Methods: Sera from different BP cohorts were tested by IIF on ME and normal human skin (NHS). To confirm findings, affinity-purified anti-BP180-NC16A/BP230 polyclonal Abs and recombinant anti-BP180-NC16A/BP230 monoclonal antibodies (mAbs) were used., Results: For sensitive detection of BP180-NC16A-specific IgG Abs, sections of NHS are superior to the widely used ME. Confirmation comes from polyclonal affinity-purified anti-BP180-NC16A/BP230 Abs, and by mAbs cloned from a patient with active BP., Conclusions: Use of NHS is preferable over ME in routine IIF testing for BP. These results are of clinical relevance because anti-BP180-NC16A IgG titres are correlated to disease activity and detecting them reliably is important for screening, diagnosis and follow-up of patients with BP., (© 2018 British Association of Dermatologists.)

Aims: To determine the impact of permanent cardiac pacing after transcatheter aortic valve implantation (TAVI) with the CoreValveTM prosthesis in terms of all-cause mortality and morbidity [rehospitalizations for heart failure (HF) or stroke] at the long-term follow-up., Methods and Results: The prospective analysis comprised 259 patients (138 women, 53.3%, age 78 ± 6 years) treated by a CoreValveTM prosthesis from April 2008 to December 2015. Forty-two patients were excluded for analysis: 9 with pre-existing permanent pacemaker (PPM) implantation, 19 who required a PPM during the follow-up and 14 patients because of hospital mortality during or after the CoreValveTM prosthesis implantation procedure. The remaining 217 patients were divided in two groups: Group-1 included those patients who required a PPM immediately after TAVI, and Group-2 included those patients who did not require permanent cardiac pacing at the long-term follow-up. Patients received follow-up at 1-month, 6-months, 12-months, and yearly thereafter. A total of 39 patients required a PPM immediately after TAVI (15.0%), but 178 patients (68.7%) did not. The mean follow-up was 37 ± 27 months (range 3-99 months) in both groups. There was no difference between the two groups in terms of all-cause mortality (52.6% vs. 56.8%, P = 0.125; HR 1.22 [0.87-1.77, 95% CI]), or stroke (13.3% vs. 15.1% P = 0.842; HR 1.12 [0.37-3.32, 95% CI]). However, patients who underwent PPM implantation developed an increase in readmissions for HF (21.1% vs. 31.9%, P = 0.015; HR 1.82 [1.23-3.92, 95% CI])., Conclusion: Patients requiring a PPM after TAVI did not have an increase in mortality, or an increase in the likelihood of developing a stroke at a long-term follow-up. However, this subgroup of patients showed an increase in rehospitalization due to HF at medium- and long-term follow-up.

Aims: State-of-the-art bioaerosol samplers have poor collection efficiencies for ultrafine virus aerosols. This work evaluated the performance of a novel growth tube collector (GTC), which utilizes laminar-flow water-based condensation to facilitate particle growth, for the collection of airborne MS2 viruses., Methods and Results: Fine aerosols (<500 nm) containing MS2 coliphage were generated from a Collison nebulizer, conditioned by a dilution dryer and collected by a GTC and a BioSampler. The GTC effectively condensed water vapour onto the virus particles, creating droplets 2-5 μm in diameter, which facilitated collection. Comparison of particle counts upstream and downstream revealed that the GTC collected >93% of the inlet virus particles, whereas the BioSampler's efficiency was about 10%. Viable counts of the GTC-collected viruses were also one order of magnitude higher than those of the BioSampler (P = 0·003)., Conclusion: The efficiency of the GTC for the viable collection of MS2 viruses exceeds that of industry standard instrument, the BioSampler, by a factor of 10-100., Significance and Impact of the Study: This study reveals that the GTC is an effective collector of viable MS2 aerosols, and concludes the instrument will be an effective tool for studying viable virus aerosols and the inhalation risks posed by airborne viruses., (© 2016 The Society for Applied Microbiology.)

Background: Pemphigus is an organ-specific autoimmune bullous disease., Objectives: To determine the role of regulatory B cells (Bregs) in patients with pemphigus., Methods: The frequency of the occurrence of CD19(+) CD24(hi) CD38(hi) Bregs was detected from 34 patients with pemphigus and 20 healthy controls. Interleukin (IL)-10 secretion was processed after stimulating B cells. Specific antidesmoglein antibody (Ab) titres and their subclasses were also measured. Ab response and cytokine production from peripheral blood mononuclear cells (PBMCs) with or without Bregs were analysed., Results: The number of Bregs was significantly increased in patients with pemphigus compared with healthy controls (15 ± 7% vs. 9 ± 3%; P < 0·01) and the proportion of Bregs in the active groups (newly diagnosed and chronic active patients) was significantly higher than in remittent individuals (16 ± 7% vs. 13 ± 8%; P = 0·04). The IL-10-producing B cells were significantly increased upon stimulation both in patients and in healthy controls. However, the increase ratio of IL-10-producing B cells between short- and long-term stimulation was significantly lower in patients with pemphigus (1·0-fold vs. 2·6-fold increase in control group; P < 0·01). Strikingly, Bregs from the controls were able to suppress interferon (IFN)-γ expression and T helper cell 1 (Th1) immune response (26% inhibition rate), while the suppressive function of Bregs from patients with pemphigus was significantly decreased (9% inhibition rate). There was no difference in Ab levels from PBMCs with or without Bregs after stimulation., Conclusions: Bregs in patients with pemphigus are elevated but with defective regulatory function on Th1 cells., (© 2014 British Association of Dermatologists.)

Pemphigus vulgaris (PV) is a severe autoimmune bullous disease involving both the skin and mucosal areas, and characterized by intraepithelial flaccid blisters and erosions. The pathogenesis of this disease is not yet completely understood, but novel insights into desmoglein biology and autoantibody pathogenesis have recently been published. Acantholysis in PV seems to result from a collective action of autoantibodies against various keratinocyte self antigens, of which desmogleins 1 and 3 are the most important. Additional antigens including desmocollins and nondesmosome components, such as the mitochondrion, might take part in disease activation. Recently, apoptosis was reported as a possible underlying mechanism of acantholysis. Furthermore, apoptolysis is believed to be the link between suprabasal acantholytic and cell-death pathways. We review the possible hypotheses of the pathogenesis of PV: the desmoglein compensation theory, the antibody-induced apoptosis theory, the basal-cell shrinkage hypothesis and the newly published apoptolysis theory., (© The Author(s). CED © 2011 British Association of Dermatologists.)

Background: Pachyonychia congenita (PC) is a group of autosomal dominant ectodermal dysplasias caused by mutations in four differentiation-specific keratin genes. Two major clinical subtypes of PC have been generally recognized. Symmetrically thickened fingernails and toenails are the defining characteristic of PC type 2 (PC-2) with onset at infancy. Pilosebaceous cysts are the best hallmark of PC-2, but they usually occur at puberty., Objectives: To report a Chinese pedigree of PC-2 with unusually early onset sebaceous cysts and to explore the genetic mutation and its phenotype., Methods: Exon 1 of keratin 17 was amplified by polymerase chain reaction (PCR) from genomic DNA from the three patients in the pedigree, the proband, his half-sister and his younger son, two unaffected members in the pedigree and 50 unrelated and unaffected people. PCR products were directly sequenced to detect the mutation., Results: Direct sequencing of the PCR products revealed a heterozygous 275A-->G mutation in all three affected members. This mutation predicts the substitution of asparagine by serine in codon 92 (N92S) located in the 1A domain of keratin 17., Conclusions: Mutation in the 1A domain of keratin 17 underlies the affected members' phenotype, PC-2 with early onset sebaceous cysts and late-onset thickened fingernails and toenails. The onset of the cysts is very early in some people within this family and the age at onset of thickened fingernails and toenails is variable within the family, implying the existence of modifying factors.