Towards global consensus on core outcomes for hidradenitis suppurativa research: an update from the HISTORIC consensus meetings I and II.

BACKGROUND: A core outcomes set (COS) is an agreed minimum set of outcomes that should be measured and reported in all clinical trials for a specific condition. Hidradenitis suppurativa (HS) has no agreed-upon COS. A central aspect in the COS development process is to identify a set of candidate outcome domains from a long list of items. Our long list had been developed from patient interviews, a systematic review of the literature and a healthcare professional survey, and initial votes had been cast in two e-Delphi surveys. In this manuscript, we describe two in-person consensus meetings of Delphi participants designed to ensure an inclusive approach to generation of domains from related items. OBJECTIVES: To consider which items from a long list of candidate items to exclude and which to cluster into outcome domains. METHODS: The study used an international and multistakeholder approach, involving patients, dermatologists, surgeons, the pharmaceutical industry and medical regulators. The study format was a combination of formal presentations, small group work based on nominal group theory and a subsequent online confirmation survey. RESULTS: Forty-one individuals from 13 countries and four continents participated. Nine items were excluded and there was consensus to propose seven domains: disease course, physical signs, HS-specific quality of life, satisfaction, symptoms, pain and global assessments. CONCLUSIONS: The HISTORIC consensus meetings I and II will be followed by further e-Delphi rounds to finalize the core domain set, building on the work of the in-person consensus meetings.

Coordinated clearance of periciliary liquid and mucus from airway surfaces.

Airway surface liquid is comprised of mucus and an underlying, watery periciliary liquid (PCL). In contrast to the well-described axial transport of mucus along airway surfaces via ciliary action, theoretical analyses predict that the PCL is nearly stationary. Conventional and confocal microscopy of fluorescent microspheres and photoactivated fluorescent dyes were used with well-differentiated human tracheobronchial epithelial cell cultures exhibiting spontaneous, radial mucociliary transport to study the movements of mucus and PCL. These studies showed that the entire PCL is transported at approximately the same rate as mucus, 39.2+/-4.7 and 39.8+/-4.2 micrometer/sec, respectively. Removing the mucus layer reduced PCL transport by > 80%, to 4.8+/-0.6 micrometer/sec, a value close to that predicted from theoretical analyses of the ciliary beat cycle. Hence, the rapid movement of PCL is dependent upon the transport of mucus. Mucus-dependent PCL transport was spatially uniform and exceeded the rate expected for pure frictional coupling with the overlying mucus layer; hence, ciliary mixing most likely accelerates the diffusion of momentum from mucus into the PCL. The cephalad movement of PCL along airway epithelial surfaces makes this mucus-driven transport an important component of salt and water physiology in the lung in health and disease.

Beware Cold Agglutinins in Organ Donors! Ex Vivo Lung Perfusion From an Uncontrolled Donation After Circulatory-Determination-of-Death Donor With a Cold Agglutinin: A Case Report.

BACKGROUND: We began to recover lungs from uncontrolled donation after circulatory determination of death to assess for transplant suitability by means of ex vivo lung perfusion (EVLP) and computerized tomographic (CT) scan. Our first case had a cold agglutinin with an interesting outcome. CASE REPORT: A 60-year-old man collapsed at home and was pronounced dead by Emergency Medical Services personnel. Next-of-kin consented to lung retrieval, and the decedent was ventilated and transported. Lungs were flushed with cold Perfadex, removed, and stored cold. The lungs did not flush well. Medical history revealed a recent hemolytic anemia and a known cold agglutinin. Warm nonventilated ischemia time was 51 minutes. O2-ventilated ischemia time was 141 minutes. Total cold ischemia time was 6.5 hours. At cannulation for EVLP, established clots were retrieved from both pulmonary arteries. At initiation of EVLP with Steen solution, tiny red aggregates were observed initially. With warming, the aggregates disappeared and the perfusate became red. After 1 hour, EVLP was stopped because of florid pulmonary edema. The lungs were cooled to 20°C; tiny red aggregates formed again in the perfusate. Ex vivo CT scan showed areas of pulmonary edema and a pyramidal right middle lobe opacity. Dissection showed multiple pulmonary emboli-the likely cause of death. However, histology showed agglutinated red blood cells in the microvasculature in pre- and post-EVLP biopsies, which may have contributed to inadequate parenchymal preservation. CONCLUSIONS: Organ donors with cold agglutinins may not be suitable owing to the impact of hypothermic preservation.

Further Evidence for Bats as the Evolutionary Source of Middle East Respiratory Syndrome Coronavirus.

The evolutionary origins of Middle East respiratory syndrome (MERS) coronavirus (MERS-CoV) are unknown. Current evidence suggests that insectivorous bats are likely to be the original source, as several 2c CoVs have been described from various species in the family Vespertilionidae Here, we describe a MERS-like CoV identified from a Pipistrellus cf. hesperidus bat sampled in Uganda (strain PREDICT/PDF-2180), further supporting the hypothesis that bats are the evolutionary source of MERS-CoV. Phylogenetic analysis showed that PREDICT/PDF-2180 is closely related to MERS-CoV across much of its genome, consistent with a common ancestry; however, the spike protein was highly divergent (46% amino acid identity), suggesting that the two viruses may have different receptor binding properties. Indeed, several amino acid substitutions were identified in key binding residues that were predicted to block PREDICT/PDF-2180 from attaching to the MERS-CoV DPP4 receptor. To experimentally test this hypothesis, an infectious MERS-CoV clone expressing the PREDICT/PDF-2180 spike protein was generated. Recombinant viruses derived from the clone were replication competent but unable to spread and establish new infections in Vero cells or primary human airway epithelial cells. Our findings suggest that PREDICT/PDF-2180 is unlikely to pose a zoonotic threat. Recombination in the S1 subunit of the spike gene was identified as the primary mechanism driving variation in the spike phenotype and was likely one of the critical steps in the evolution and emergence of MERS-CoV in humans.IMPORTANCE Global surveillance efforts for undiscovered viruses are an important component of pandemic prevention initiatives. These surveys can be useful for finding novel viruses and for gaining insights into the ecological and evolutionary factors driving viral diversity; however, finding a viral sequence is not sufficient to determine whether it can infect people (i.e., poses a zoonotic threat). Here, we investigated the specific zoonotic risk of a MERS-like coronavirus (PREDICT/PDF-2180) identified in a bat from Uganda and showed that, despite being closely related to MERS-CoV, it is unlikely to pose a threat to humans. We suggest that this approach constitutes an appropriate strategy for beginning to determine the zoonotic potential of wildlife viruses. By showing that PREDICT/PDF-2180 does not infect cells that express the functional receptor for MERS-CoV, we further show that recombination was likely to be the critical step that allowed MERS to emerge in humans.

Lung stem cell update: promise and controversy.

Currently, there is great enthusiasm about potential stem cell therapies for intractable diseases. We previously reviewed the topic of stem cells in lung injury and repair, including the role of endogenous, tissue (somatic) stem cells and the contribution of circulating cells to the lung parenchyma. Our purpose here is to provide a concise update in this fast-moving field. New information and ongoing debate focus attention on basic issues in lung stem cell biology and highlight the need for additional studies to establish the feasibility of cell therapies to prevent or treat lung diseases.

Cytochemical localization and biochemical evaluation of a lysosomal serine protease in lung: dipeptidyl peptidase II in the normal rat.

Dipeptidyl peptidase II (DPP II) in normal rat lung was evaluated by the enzymes' ability to hydrolyze Lys-Ala or Lys-Pro derivatives of 4-methoxy-2-naphthylamine (MNA). For visualization of this activity, the liberated MNA was coupled with fast blue B for light microscopy (LM) or hexazotized pararosaniline with osmication for electron microscopy (EM). Granular to diffuse reaction product was noted in many lung cells in frozen sections for LM, including alveolar and tissue macrophages, fibroblasts, chondrocytes, bronchial and bronchiolar epithelial cells and mast cells. Reaction product at the EM level was seen in the lysosomal structures of the above cells, although lysosomal heterogeneity with regard to reactivity was noted. Cellular content of reaction product by EM correlated with LM staining intensity. Additional structures, not obviously reactive by LM, such as the lamellar bodies of type II cells and lysosomes in other cell types, were seen to contain reaction product ultrastructurally. A modified biochemical assay for the quantitation of DPP II in tissue homogenates was used to determine the activity of the enzyme in rat lung. Enzyme activity in polyacrylamide isoelectric focusing gels indicate that Lys-Ala-MNA was the more specific substrate but, by virtue of its rapid hydrolysis, Lys-Pro-MNA was more sensitive.

Cell type-specific lectin staining of the tracheobronchial epithelium of the rat: quantitative studies with Griffonia simplicifolia I isolectin B4.

We compared lectin staining patterns to cell population densities, as determined by morphological criteria in rat airways. Eight lectins were studied: Griffonia simplicifolia I isolectin B4 (GSI-B4), Arachis hypogaea (PNA), Wisteria floribunda (WFA), Glycine maximus (SBA), Dolichos biflorus (DBA), Helix pomatia (HPA), Ulex europaeus (UEA-1), and Maclura pomifera (MPA). Two of the lectins strongly stained morphologically distinct cell subpopulations. GSI-B4 stained basal cells, and MPA stained non-ciliated bronchiolar (Clara) cells. The specificity and sensitivity of GSI-B4 as a marker for basal cells was examined. In the trachea, 35% of all cells were GSI-B4 positive; 84% of these were basal cells, 7% were unidentified cells, 5% were serous/mucous cells, and 4% were ciliated, brush, or inflammatory cells. Comparison to cell population density data strongly suggested that all basal cells were GSI-B4 positive. The segmental bronchus was a transitional area; GSI-B4 positive basal cells were present in the region closest to the lobar bronchus but were absent in the distal region; instead, MPA-positive Clara cells appeared. When dissociated tracheal cells were obtained by pronase digestion, 43% were GSI-B4 positive. These results show that GSI-B4 is a sensitive and relatively specific marker for basal cells in the rat trachea which can be used to study dissociated epithelial cells.

Biochemical quantitation and histochemical localization of cathepsin B, dipeptidyl peptidases I and II, and acid phosphatase in pulmonary granulomatosis and fibrosis in rats.

The purpose of this study was to quantitate biochemically and to localize histochemically the proteases cathepsin B (Cath B), dipeptidyl peptidase I (DPP I), and dipeptidyl peptidase II (DPP II) in experimental pulmonary granulomatosis and fibrosis. These were compared to the prototypical lysosomal hydrolase acid phosphatase (AP). Granulomatosis was induced by the intravenous injection of complete Freund's adjuvant (CFA, 0.2 ml) and fibrosis was induced by the intratracheal instillation of bleomycin sulfate (1 unit) in rats (Wistar, 200 g). Total Cath B, DPP I, and AP activities were markedly elevated over control values five days following both treatments when expressed as activity per lung or as specific activity per milligram protein or milligram DNA. By 14 and 28 days, total activity was elevated for all three enzymes, and activity per milligram DNA remained elevated for Cath B following both treatments and for DPP I 28 days following CFA treatment. Total lung activity of DPP II was significantly elevated at 28 days for both treatments. Histochemical staining indicated that these changes are due, in part, to the influx of inflammatory monocytes and their maturation to macrophages. This study provides a basis for examining the role of these proteases in connective tissue matrix injury during inflammatory processes in the lungs.

Rat tracheal epithelial cell differentiation in vitro.

In vitro culture conditions enabling rat tracheal epithelial (RTE) cells to differentiate to mucociliary, mucous, or squamous phenotypes are described. Medium composition for rapid cell growth to confluence in membrane insert cultures was determined, and the effects of major modifiers of differentiation were tested. Retinoic acid (RA), collagen gel substratum, and an air-liquid interface at the level of the cell layer were required for expression of a mucociliary phenotype which most closely approximated the morphology of the tracheal epithelium in vivo. Large quantities of high molecular weight, hyaluronidase-resistant glycoconjugates, most likely mucin glycoproteins, were produced in the presence of RA when the cells were grown with or without a collagen gel and in submerged as well as in interface cultures. However, extensive ciliagenesis was dependent on the simultaneous presence of RA, collagen gel, and an air-liquid interface. When RA was omitted from the media, the cells became stratified squamous and developed a cornified apical layer in air-liquid interface cultures. This phenotype was accompanied by loss of transglutaminase (TGase) type II and keratin 18 and expression of the squamous markers TGase type I and keratin 13. The ability to modulate RTE cell phenotypes in culture will facilitate future studies investigating molecular regulation of tracheal cell proliferation, differentiation, and function.

Rat tracheal epithelial cell differentiation in vitro.

In vitro culture conditions enabling rat tracheal epithelial (RTE) cells to differentiate to mucociliary, mucous, or squamous phenotypes are described. Medium composition for rapid cell growth to confluence in membrane insert cultures was determined, and the effects of major modifiers of differentiation were tested. Retinoic acid (RA), collagen gel substratum, and an air-liquid interface at the level of the cell layer were required for expression of a mucociliary phenotype which most closely approximated the morphology of the tracheal epithelium in vivo. Large quantities of high molecular weight, hyaluronidase-resistant glycoconjugates, most likely mucin glycoproteins, were produced in the presence of RA when the cells were grown with or without a collagen gel and in submerged as well as in interface cultures. However, extensive ciliagenesis was dependent on the simultaneous presence of RA, collagen gel, and an air-liquid interface. When RA was omitted from the media, the cells became stratified squamous and developed a cornified apical layer in air-liquid interface cultures. This phenotype was accompanied by loss of transglutaminase (TGase) type II and keratin 18 and expression of the squamous markers TGase type I and keratin 13. The ability to modulate RTE cell phenotypes in culture will facilitate future studies investigating molecular regulation of tracheal cell proliferation, differentiation, and function.

Isolation and culture of airway epithelial cells from chronically infected human lungs.

We describe procedures for isolating and culturing airway epithelial cells from chronically infected human lungs. Experience in our laboratory demonstrated the need to balance pathogen eradication against antibiotic toxicity to epithelial cells. To provide a logical basis for antibiotic selection and dose, we systematically analyzed the cytotoxicity of antibiotics useful against typical pathogens. Alone, colistin, ciprofloxacin, doxycycline, and tobramycin were moderately toxic at concentrations close to those used in cell culture, whereas amphotericin, ceftazidime, chloramphenicol, imipenem, meropenem, piperacillin, sulfamethoxazole/trimethoprim, and vancomycin were nontoxic even at concentrations many times the antimicrobial level. Epithelial cytotoxicity of combined antibiotics was additive, with no evidence of competition or synergism. Antibiotics had little effect on initial cell attachment and did not acutely lyse cells, but inhibited subsequent growth. Interestingly, cytotoxicity decreased markedly with increasing epithelial cell density. Cystic fibrosis (CF) and non-CF epithelial cells showed no differences in sensitivity to the antibiotics tested and initial exposure to antibiotics did not affect the electrophysiologic properties of resistance or short circuit current in well-differentiated cells. Tailored combinations of antibiotics at appropriate doses killed even multidrug-resistant bacteria. Thus, epithelial cells can usually be cultured from chronically infected CF airways.

Mucin production in the middle ear in response to lipopolysaccharides.

OBJECTIVE: This study examined the response of middle ear tissue to establish the lowest dose of lipopolysaccharide to induce mucin production in a rat otitis media model. METHODS: Twenty-six male Sprague-Dawley rats' eustachian tubes were obstructed before transtympanic inoculation of the bulla tympanica with 35 microL of Krebs Ringer or 1, 10, 100, or 1000 microgram/mL lipopolysaccharide. After 7 days the effusion and a lavage were collected for mucin ELISA measurement, and tissue was collected for histologic evaluation. RESULTS: Mucin secretion was significantly increased in the 100 microgram/mL 51.20 +/- 13.6 microgram/mL (SE) and 1000 microgram/mL 69.42 +/- 8.57 microgram/mL groups when compared with the Krebs Ringer control group 1.84 +/- 0.28 microgram/mL (P < 0.05). Histologic evaluation shows goblet cell metaplasia and hyperplasia in the middle ear epithelium in the 1000 and 100 microgram/mL groups. CONCLUSIONS: The histology and ELISA results suggest that a middle ear effusion is generated with a dose of lipopolysaccharide as low as 100 microgram/mL.

Nitric oxide mediates mucin secretion in endotoxin-induced otitis media with effusion.

The mechanisms that regulate mucin release in chronic otitis media with effusion, a leading cause of hearing loss in children, remain largely unknown. We developed an animal model using Sprague-Dawley rats to determine the factors responsible for mucin production in chronic otitis media with effusion. N-nitro-L-arginine methyl ester (L-NAME), a competitive inhibitor of nitric oxide synthase, was used to investigate the role of nitric oxide in mucin secretion by the middle ear epithelium. All rats underwent eustachian tube obstruction. In the first set of rats, the middle ear was then injected transtympanically with 35 microl of either 300 mOsm Krebs-Ringer bicarbonate buffer (control group) or 1 mg/ml lipopolysaccharide in Krebs-Ringer (experimental group 1). In a second set of rats, the middle ear space was injected with lipopolysaccharide and then infused at a continuous rate for 7 days with either Krebs-Ringer (experimental group 2) or 1 mmol/L L-NAME in Krebs-Ringer (experimental group 3) through an osmotic infusion pump. After 7 days the volume of effusion and the quantity of mucin collected were significantly greater in lipopolysaccharide-exposed ears than in controls. In addition, antimucin immunostaining demonstrated mucous cell hyperplasia in response to lipopolysaccharide. The lipopolysaccharide-induced production of mucin and mucous cell hyperplasia was inhibited in ears treated with lipopolysaccharide and L-NAME. These results suggest that nitric oxide is a mediator in the pathway of mucin secretion in chronic otitis media with effusion.

Intestinal permeability testing using lactulose and rhamnose: a comparison between clinically normal cats and dogs and between dogs of different breeds.

In the experiment reported here, the lactulose/rhamnose urinary excretion test was used to compare intestinal permeability between four breeds of healthy adult dogs and a group of healthy adult cats. A significant difference in permeability was found between dogs and cats (P <0.001) and between different breeds of dogs (P <0.005). The range of urinary lactulose/rhamnose ratios in the dogs in this study (0.07-0.61) was wider than previously reported (0.03-0.12). The mean value for dogs was 0.19. The range in cats was 0.41-1.25 and the mean 0.52. The results of this study suggest that breed or some other factor such as environment, diet or sexual status as well as species should be taken into account when assessing intestinal permeability using the lactulose/rhamnose urinary excretion test.

Incorporating care for the special patient into general dental practice.

The training of general dental practitioners in a program that emphasizes the care of the special patient is described. Each trainee donates one day a week to the Illinois Masonic Medical Center, which pays all practice expenses, and a referral network is being developed among those who have completed the course.

Comparison of plasma benzodiazepine concentrations following intranasal and intravenous administration of diazepam to dogs.

OBJECTIVE: To determine whether plasma concentrations of benzodiazepines (BDZ) in dogs following intranasal (IN) administration of diazepam are comparable to concentrations following IV administration. ANIMALS: 6 (4 male, 2 female) healthy adult Greyhounds. PROCEDURE: Dogs were randomly assigned to 2 groups of 3 dogs in a crossover design. Diazepam (0.5 mg/kg of body weight) was administered intravenously to dogs in group 1 and intranasally to dogs in group 2. Blood was collected from the jugular vein of each dog into tubes containing lithium heparin before and 3, 6, 9, 12, 15, 20, 30, 60, 120, 240, and 480 minutes following diazepam administration. After a 4-day washout period, dogs in group 1 received diazepam intranasally, dogs in group 2 received diazepam intravenously, and blood was again collected. Plasma concentration of BDZ was determined by use of a fluorescence polarization immunoassay. RESULTS: Mean (+/- SD) peak plasma concentration of BDZ following IV administration (1,316 +/- 216 microg/L) was greater than that following IN administration (448 +/- 41 microg/L). Time to peak concentration was < or = 3 minutes following IV administration and 4.5 +/- 1.5 minutes following IN administration. Mean bioavailability of BDZ following IN administration was 80 +/- 9%. CONCLUSIONS AND CLINICAL RELEVANCE: Diazepam is rapidly and efficiently absorbed following IN administration of the parenteral formulation. Plasma concentrations match or exceed the suggested therapeutic concentration (300 microg/L). Intranasal administration of diazepam may be useful for treatment of seizures in dogs by owners or when intravenous access is not readily available.

Avoiding patient injury during general anesthesia.

Attention to detail when preparing a dental patient for rehabilitation utilizing general anesthesia will prevent a variety of positional and traumatic injuries. The dentist and anesthesiologist must anticipate potential hazards to the unconscious patient.

Dental Trauma and Disease in 34 Professional Athletes.

In brief: As part of the preseason general physical examination, 34 football players were given dental examinations. In addition to routine dental caries and gingival inflammation, 18 athletes had dental problems that could potentially interfere with the competitive season: retained root tips, abscessed teeth, pulpally exposed carious teeth, and seriously impacted third molars. Nine players had sustained injuries to the maxillary anterior teeth, many of which could have been prevented by customized mouth guards.

Mucus clearance, MyD88-dependent and MyD88-independent immunity modulate lung susceptibility to spontaneous bacterial infection and inflammation.

It has been postulated that mucus stasis is central to the pathogenesis of obstructive lung diseases. In Scnn1b-transgenic (Scnn1b-Tg⁺ mice, airway-targeted overexpression of the epithelial Na⁺ channel ß subunit causes airway surface dehydration, which results in mucus stasis and inflammation. Bronchoalveolar lavage from neonatal Scnn1b-Tg⁺ mice, but not wild-type littermates, contained increased mucus, bacteria, and neutrophils, which declined with age. Scnn1b-Tg⁺ mice lung bacterial flora included environmental and oropharyngeal species, suggesting inhalation and/or aspiration as routes of entry. Genetic deletion of the Toll-interleukin-1 receptor adapter molecule MyD88 in Scnn1b-Tg⁺ mice did not modify airway mucus obstruction, but caused defective neutrophil recruitment and increased bacterial infection, which persisted into adulthood. Scnn1b-Tg⁺ mice derived into germ-free conditions exhibited mucus obstruction similar to conventional Scnn1b-Tg⁺ mice and sterile inflammation. Collectively, these data suggest that dehydration-induced mucus stasis promotes infection, compounds defects in other immune mechanisms, and alone is sufficient to trigger airway inflammation.