Development of a core outcome set for cutaneous squamous cell carcinoma trials: identification of core domains and outcomes.

BACKGROUND: The lack of uniformity in the outcomes reported in clinical studies of the treatment of cutaneous squamous cell carcinoma (cSCC) complicates efforts to compare treatment effectiveness across trials. OBJECTIVES: To develop a core outcome set (COS), a minimum set of agreed-upon outcomes to be measured in all clinical trials of a given disease or outcome, for the treatment of cSCC. METHODS: One hundred and nine outcomes were identified via a systematic literature review and interviews with 28 stakeholders. After consolidation of this long list, 55 candidate outcomes were rated by 19 physician and 10 patient stakeholders, in two rounds of Delphi exercises. Outcomes scored 'critically important' (score of 7, 8 or 9) by ≥ 70% of patients and ≥ 70% of physicians were provisionally included. At the consensus meeting, after discussion and voting of 44 international experts and patients, the provisional list was reduced to a final core set, for which consensus was achieved among all meeting participants. RESULTS: A core set of seven outcomes was finalized at the consensus meeting: (i) serious or persistent adverse events, (ii) patient-reported quality of life, (iii) complete response, (iv) partial response, (v) recurrence-free survival, (vi) progression-free survival and (vii) disease-specific survival. CONCLUSIONS: In order to increase the comparability of results across trials and to reduce selective reporting bias, cSCC researchers should consider reporting these core outcomes. Further work needs to be performed to identify the measures that should be reported for each of these outcomes.

Comparison of electric hand dryers and paper towels for hand hygiene: a critical review of the literature.

Numerous studies are published on the benefits of electric hand dryers vs paper towels (PT) for drying hands after washing. Data are conflicting and lacking key variables needed to assess infection risks. We provide a rapid scoping review on hand-drying methods relative to hygiene and health risks. Controlled vocabulary terms and keywords were used to search PubMed (1946-2018) and Embase (1947-2018). Multiple researchers independently screened abstracts for relevance using predetermined criteria and created a quality assessment scoring system for relative study comparisons. Of 293 papers, 23 were included in the final analysis. Five studies did not compare multiple methods; however, 2 generally favoured electric dryers (ED); 7 preferred PT; and 9 had mixed or statistically insignificant results (among these, 3 contained scenarios favourable to ED, 4 had results supporting PT, and the remaining studies had broadly conflicting results). Results were mixed among and within studies and many lacked consistent design or statistical analysis. The breadth of data does not favour one method as being more hygienic. However, some authors extended generalizable recommendations without sufficient scientific evidence. The use of tools in quantitative microbial risk assessment is suggested to evaluate health exposure potentials and risks relative to hand-drying methods. We found no data to support any human health claims associated with hand-drying methods. Inconclusive and conflicting results represent data gaps preventing the advancement of hand-drying policy or practice recommendations.

Falling through the cracks. A thematic evaluation of unmet needs of adult survivors of childhood cancers.

OBJECTIVE: The population of adult survivors of childhood cancers (ASCCs) is growing, resulting in unique long-term challenges. This study explored experiences of perceived unmet ASCC survivorship needs. METHODS: We invited ASCCs to complete surveys sent through the cancer registry. Four open-ended questions allowed participants to write in comments. We analyzed responses to these open-ended questions thematically, employing a process of constant comparison. RESULTS: Our sample included 94 ASCCs who completed open-ended questions (61 female; aged 20-78 years, mean age = 34.47, SD = 11.84, mean = 23.27 years post diagnosis). Identified themes included (1) overlooked experiences of distress; (2) lack of counseling: system, patient, and family barriers; (3) difficulty negotiating future life milestones exacerbated by lack of knowledge; and (4) dissatisfaction with service provision: past and present. Prevalent issues identified by participants included lack of supportive care to address needs, distress due to missed developmental milestones as a result of cancer, lack of knowledge about late-term and long-term effects of cancer treatment, and concern over absence of organized long-term follow-up. CONCLUSIONS: Adult survivors of childhood cancers continue to experience unmet needs during their cancer diagnosis, treatment, and long into survivorship due to the treatment for cancer and ongoing side effects. Solutions could focus on addressing the needs of survivors to bridge system gaps and barriers. Specifically, there is a need to improve psychological interventions and transitions from pediatric to adult-care facilities.

Impact of disinfectant wipes on the risk of Campylobacter jejuni infection during raw chicken preparation in domestic kitchens.

AIMS: In the present study, we conducted a quantitative microbial risk assessment forecasting the exposure to Campylobacter jejuni contaminated surfaces during preparation of chicken fillets and how using a disinfectant-wipe intervention to clean a contaminated work area decreases the risk of infection following the preparation of raw chicken fillet in a domestic kitchen. METHODS AND RESULTS: Using a Monte Carlo simulation of the risk of transferring Camp. jejuni strain A3249, from various surfaces to hands and subsequently transferring it to the mouth was forecasted. The use of a disinfectant-wipe intervention to disinfect contaminated surface area was also assessed. Several assumptions were used as input parameters in the classical Beta-Poisson model to determine the risk of infection. The disinfectant-wipe intervention reduced the risk of Camp. jejuni infection by 2-3 orders on all fomites. CONCLUSIONS: The use of disinfectant wipes after the preparation of raw chicken meat reduces the risk of Camp. jejuni infections. SIGNIFICANCE AND IMPACT OF THE STUDY: This risk assessment shows that the use of disinfectant wipes to decontaminate surface areas after chicken preparation reduces the annual risk of Camp. jejuni infections up to 99·2%, reducing the risk from 2 : 10 to 2 : 1000.

Maladaptive health factors as potential mediators for the association between posttraumatic stress disorder and cardiovascular disease: A sex-stratified analysis in the U.S. adult population.

OBJECTIVES: This study examined sex differences for health risk factors as potential mediators in the association between posttraumatic stress disorder (PTSD) and cardiovascular disease (CVD). METHODS: Secondary data from the 2012-2013 National Epidemiological Survey on Alcohol and Related Conditions Wave 3 was used. This cross-sectional survey contains a nationally representative sample of 36,309 U.S. adults (nfemales = 20,447, Mage = 47.16, 95% CI = [46.74, 47,57]; nmales = 15,682, Mage = 45.88, 95% CI = [45.42, 46.34]). Natural effect models and logistic regression analyses were conducted to evaluate health risk factors (smoking, substance use, low physical activity, high body mass index [BMI], binge eating, and multiple health risk factors) as potential mediators for the PTSD-CVD relationship in females and males. RESULTS: High BMI (indirect AOR = 1.05, 95% CI = [1.02, 1.07]) and substance use (indirect AOR = 0.93, 95% CI = [0.88, 0.98], p = 0.005) were potential mediators in females and males respectively. Binge eating, smoking, and low physical activity were not mediators in either sex. The number of health risk factors was also a potential mediator in females (indirect AOR = 1.12, 95% CI = [1.07, 1.19], p = <0.001) though not males (indirect AOR = 1.09, 95% CI = [1.00, 1.19], p = .059). CONCLUSIONS: The results inform prevention strategies, such as screening for health risk factors to mitigate the adverse effect of PTSD on CVD risk. Findings also inform important directions for future longitudinal research to establish causal pathways.

Characterizing the transition from paediatric to adult care among emerging adults with Type 1 diabetes.

AIMS: The goals of the study were to describe the transition of youth with Type 1 diabetes from paediatric to adult healthcare services, examine the link of this transition with self care and glycaemic control, and distinguish youth who received medical treatment from different physicians in terms of demographic and parent relationship variables. METHODS: Youth with Type 1 diabetes (n = 118) were enrolled in a prospective study that examined the transition from the paediatric to adult healthcare systems and were evaluated during their senior year of high school (time 1) and 1 year later (time 2). Data on self care, glycaemic control and parent relationship were collected. RESULTS: The majority of youth saw a paediatric endocrinologist at both assessments (n = 64); others saw an adult care physician at both assessments (n = 26) or transitioned from a paediatric endocrinologist to an adult care physician (n = 19). Nine youth saw no physician between time 1 and time 2. There were group differences in demographic and parent relationship variables and self-care behaviour and glycaemic control related to the transition of care. Youth who remained in the paediatric healthcare system had the best self care and did not experience declines in glycaemic control over time. CONCLUSIONS: Early transition from the paediatric healthcare system to the adult healthcare system is associated with psychosocial variables and worse glycaemic control. Future research should identify factors that determine optimal timing and strategies to avoid deterioration of care and control during this transition.

Floor and environmental contamination during glove disposal.

BACKGROUND: Evidence suggests that doffing and possibly disposal of used personal protective equipment (PPE) can lead to environmental contamination. AIM: To ascertain the potential for site and floor contamination when medical gloves are inappropriately disposed. METHODS: Fifteen healthcare workers (HCWs) disposed of gloves inoculated with bacteriophage and a chemical dye into a wastebasket, located 1.22 m away. Following each trial, designated sample areas were visually inspected with a blacklight for fluorescent dye stains and swabbed with a 3M Letheen Broth sponge to quantify the bacteriophage. FINDINGS: The area closest to the participant (<0.30 m) had the highest bacteriophage concentrations (geomean: 6.9 × 103 pfu/100 cm2; range: 8.07 to 3.93 × 107 pfu/100 cm2). Bacteriophage concentrations were significantly higher (P < 0.05) in areas ≤0.61 m compared to >0.61 m from the HCWs. Although the farthest distances (1.22-1.52 m) resulted in 14% bacteriophage- and 4% fluorescent dye-positive occurrences, there was no significant difference (P = 0.069) between the tracers. The bacteriophage and chemical dye indicate highest environmental contamination nearest the HCWs and both tracers could be appropriate for PPE disposal training. CONCLUSION: HCWs use gloves every workday and potentially could contaminate surrounding surfaces and floors, during improper disposal practices. Therefore, proper disposal techniques are required to minimize pathogen transmission by establishing industry-wide policies, adequate training, and education to HCWs.

Identification of a cyclohexylcarbonyl CoA biosynthetic gene cluster and application in the production of doramectin.

The side chain of the antifungal antibiotic ansatrienin A from Streptomyces collinus contains a cyclohexanecarboxylic acid (CHC)-derived moiety. This moiety is also observed in trace amounts of omega-cyclohexyl fatty acids (typically less than 1% of total fatty acids) produced by S. collinus. Coenzyme A-activated CHC (CHC-CoA) is derived from shikimic acid through a reductive pathway involving a minimum of nine catalytic steps. Five putative CHC-CoA biosynthetic genes in the ansatrienin biosynthetic gene cluster of S. collinus have been identified. Plasmid-based heterologous expression of these five genes in Streptomyces avermitilis or Streptomyces lividans allows for production of significant amounts of omega-cyclohexyl fatty acids (as high as 49% of total fatty acids). In the absence of the plasmid these organisms are dependent on exogenously supplied CHC for omega-cyclohexyl fatty acid production. Doramectin is a commercial antiparasitic avermectin analog produced by fermenting a bkd mutant of S. avermitilis in the presence of CHC. Introduction of the S. collinus CHC-CoA biosynthetic gene cassette into this organism resulted in an engineered strain able to produce doramectin without CHC supplementation. The CHC-CoA biosynthetic gene cluster represents an important genetic tool for precursor-directed biosynthesis of doramectin and has potential for directed biosynthesis in other important polyketide-producing organisms.

Crystal structure of a substrate complex of Mycobacterium tuberculosis beta-ketoacyl-acyl carrier protein synthase III (FabH) with lauroyl-coenzyme A.

Beta-ketoacyl-acyl carrier protein synthase III (FabH) catalyzes a two step reaction that initiates the pathway of fatty acid biosynthesis in plants and bacteria. In Mycobacterium tuberculosis, FabH catalyzes extension of lauroyl, myristoyl and palmitoyl groups from which cell wall mycolic acids of the bacterium are formed. The first step of the reaction is an acyl group transfer from acyl-coenzyme A to the active-site cysteine of the enzyme; the second step is acyl chain extension by two carbon atoms through Claisen condensation with malonyl-acyl carrier protein. We have previously determined the crystal structure of a type II, dissociated M.tuberculosis FabH, which catalyzes extension of lauroyl, myristoyl and palmitoyl groups. Here we describe the first long-chain Michaelis substrate complex of a FabH, that of lauroyl-coenzyme A with a catalytically disabled Cys-->Ala mutant of M.tuberculosis FabH. An elongated channel extending from the mutated active-site cysteine defines the acyl group binding locus that confers unique acyl substrate specificity on M.tuberculosis FabH. CoA lies in a second channel, bound primarily through interactions of its nucleotide group at the enzyme surface. The apparent weak association of CoA in this complex may play a role in the binding and dissociation of long chain acyl-CoA substrates and products and poses questions pertinent to the mechanism of this enzyme.

Polyketide synthase acyl carrier protein (ACP) as a substrate and a catalyst for malonyl ACP biosynthesis.

BACKGROUND: Using an acyl-acyl carrier protein (ACP) as a starter unit, type II polyketide synthases (PKSs) generate a wide range of polyketide products by successive decarboxylative condensations with the two-carbon donor malonyl (ACP). In vitro experiments have demonstrated that polyketide biosynthesis in reconstituted PKS systems requires the fatty acid synthase (FAS) enzyme malonyl CoA:ACP acyltransferase (FabD) from streptomycetes. It has also been shown that holo-ACPs from a type II PKS can catalyze self-malonylation in the presence of malonyl CoA and negate this FabD requirement. The relative roles of FabD and ACP self-malonylation in PKS biosynthesis in vivo are still not known. RESULTS: We have examined the ACP specificity of the Streptomyces glaucescens FabD and shown that it reacts specifically with monomeric forms of ACP, with comparable k(cat)/K(M) values for ACPs from both type II PKS and FAS systems. Incubations of tetracenomycin ACP (TcmM) with the Escherichia coli FAS ACP (AcpP) unexpectedly revealed that, in addition to the self-malonylation process, TcmM can catalyze the malonylation of AcpP. The k(cat)/K(M) value for the TcmM-catalyzed malonylation of S. glaucescens FAS ACP is two orders of magnitude smaller than that observed for the FabD-catalyzed process. CONCLUSIONS: The ability of a PKS ACP to catalyze malonylation of a FAS ACP is a surprising finding and demonstrates for the first time that PKS ACPs and FabD can catalyze the same reaction. The differences in the catalytic efficiency of these two proteins rationalizes in vitro observations that FabD-independent polyketide biosynthesis proceeds only at high concentrations of a PKS ACP.

Mechanisms of molecular recognition in the pikromycin polyketide synthase.

BACKGROUND: Modular polyketide synthases (PKSs) produce a wide range of medically significant compounds. In the case of the pikromycin PKS of Streptomyces venezuelae, four separate polypeptides (PikAI-PikAIV), comprising a total of one loading domain and six extension modules, generate the 14-membered ring macrolactone narbonolide. The polypeptide PikAIV contains a thioesterase (TE) domain and is responsible for catalyzing both the last elongation step with methylmalonyl CoA, and subsequent release of the final polyketide chain elongation intermediate from the PKS. Under certain growth conditions this polypeptide is synthesized from an alternative translational start site, giving rise to an N-terminal truncated form of PikAIV, containing only half of the ketosynthase (KS(6)) domain. The truncated form of PikAIV is unable to catalyze the final elongation step, but is able to cleave a polyketide chain from the preceding module on PikAIII (ACP(5)), giving rise to the 12-membered ring product 10-deoxymethynolide. RESULTS: S. venezuelae mutants expressing hybrid PikAIV polypeptides containing acyl carrier protein (ACP) and malonyl CoA specific acyltransferase (AT) domains from the rapamycin PKS were unable to catalyze production of 12- or 14-membered ring macrolactone products. Plasmid-based expression of a hybrid PikAIV containing the native KS(6) and TE domains, however, restored production of both narbonolide and 10-deoxymethynolide in the S. venezuelae AX912 mutant that generates a TE-deleted form of PikAIV. Use of alternative KS domains or deletion of the KS(6) domain within the hybrid PikAIV resulted in loss of both products. Plasmid-based expression of a TE domain of PikAIV as a separate polypeptide in the AX912 mutant resulted in greater than 50% restoration of 10-deoxymethynolide, but not in mutants expressing a hybrid PikAIV bearing an unnatural AT domain. Mutants expressing hybrid PikAIV polypeptides containing the natural AT(6) domains and different ACP domains efficiently produced polyketide products, but with a significantly higher 10-deoxymethynolide/narbonolide ratio than observed with native PikAIV. CONCLUSIONS: Dimerization of KS(6) modules allows in vivo formation of a PKS heterodimer using PikAIV polypeptides containing different AT and ACP domains. In such heterodimers, the TE domain and the AT(6) domain responsible for formation of the narbonolide product are located on different polypeptide chains. The AT(6) domain of PikAIV plays an important role in facilitating TE-catalyzed chain termination (10-deoxymethynolide formation) at the proceeding module in PikAIII. The pikromycin PKS can tolerate the presence of multiple forms (active and inactive) of PikAIV, and decreased efficiency of elongation by PikAIV can result in increased levels of 10-deoxymethynolide. These results provide new insight into functional molecular interactions and interdomain recognition in modular PKSs.

Use of immunoglobulin A-antiendomysial antibody to screen for celiac disease in North American children with type 1 diabetes.

OBJECTIVE: Our objective was to determine if a serological marker, the immunoglobulin A antiendomysial antibody (IgA-EMA), can be used to screen for celiac disease in North American children with type 1 diabetes. RESEARCH DESIGN AND METHODS: Subjects included 236 diabetes clinic patients and 56 gastrointestinal clinic patients who underwent intestinal biopsy for suspected malabsorption. Total IgA and IgA-EMA assays were performed. Diabetic patients who were positive for IgA-EMA were asked to undergo biopsy. RESULTS: Of 236 diabetic patients tested, none were IgA deficient and 19 were positive for IgA-EMA (8%). Of 17 patients biopsied, 12 had celiac disease and 3 were symptomatic. The estimated prevalence of celiac disease was 5.1%, consistent with data from European diabetic clinics. Of the 56 gastrointestinal clinic patients, the 3 who were IgA-EMA positive had biopsies diagnostic of celiac disease. Three were found to be IgA deficient, one of whom had celiac disease. Of the 50 IgA-sufficient and IgA-EMA-negative patients, 1 had celiac disease and 49 did not. The IgA-EMA test had a sensitivity of 94% and a specificity of 91% for IgA-sufficient biopsied patients. CONCLUSIONS: IgA-EMA is an appropriate tool for demonstrating an increased prevalence of celiac disease in a North American pediatric diabetic population. Positive testing should be confirmed by intestinal biopsy, and false-positive results require serial follow-up. Symptomatic children require biopsy regardless of their IgA-EMA status.

The Streptomyces venezuelae pikAV gene contains a transcription unit essential for expression of enzymes involved in glycosylation of narbonolide and 10-deoxymethynolide.

In Streptomyces venezuelae, four polyketide synthase (PKS) polypeptides encoded by pikAI-pikAIV are used to generate 10 and 12-membered macrocyclic structures, narbonolide and 10-deoxymethynolide. Sequence analysis suggests these genes are translationally coupled with downstream genes, pikAV (encoding a type II thioesterase), desVIII-desVI (encoding enzymes responsible for production of the final glycosylated products pikromycin, narbomycin, methymycin and neomethymycin) and desR (a resistance gene). Type II thioesterases have been suggested to have an editing function in polyketide biosynthesis and deletion of the corresponding genes often leads to decreased levels of polyketide production. Surprisingly an in-frame deletion of 687 bp of the 843 bp pikAV ORF led to a strain SC1022 that produced normal yields of polyketide products, but only in the aglycone form. Plasmid-based expression of the desVIII-VI and desR in the SC1022 strain completely restored production of glycosylated products, despite the absence of a functional pikAV gene product. Under these conditions the PikAV TEII therefore does not play an important role in polyketide biosynthesis, and its function remains an enigma. These observations also demonstrate that the region of pikAV DNA deleted in strain SC1022 contains a transcription unit essential for expression of the des genes. A sequence alignment of PikAV with members of the highly conserved type II thioesterases revealed a short divergent region at the carboxy terminus, suggesting a region of pikAV that might contain such a transcription unit. DNA containing this region of pikAV was shown to be able to increase plasmid-based expression of both crotonyl CoA reductase gene (ccr) and the erythromycin resistance gene (ermE) in S. venezuelae.

In vivo analysis of straight-chain and branched-chain fatty acid biosynthesis in three actinomycetes.

The starter units for branched-chain and straight-chain fatty acid biosynthesis was investigated in vivo in three actinomycetes using stable isotopes. Branched-chain fatty acids, which constitute the majority of the fatty acid pool, were confirmed to be biosynthesized using the amino acid degradation products methylbutyrl-CoA and isobutyrl-CoA as starter units. Straight-chain fatty acids were shown to be constructed using butyrl-CoA as a starter unit. Isomerization of the valine catabolite isobutyryl-CoA was shown to be only a minor source of this butyryl-CoA.

Isotopically sensitive regioselectivity in the oxidative deamination of a homologous series of diamines catalyzed by diamine oxidase.

The equivalence of aminomethylene groups in selected diamine substrates of diamine oxidase was exploited for the determination of intramolecular isotope effects. In the series of substrates, [1,1-2H2]-1,3-diaminopropane, [1,1-2H2]-1,5-diaminopentane, [1,1-2H2]-1,6-diaminohexane, [1,1-2H2]-1,7-diaminoheptane and [alpha,alpha-2H2]-4-(aminomethyl)benzylamine, the preference of the enzyme for reaction at the unlabeled methylene was found to vary from 1.45 to 10.5-fold. The observed partitioning ratios go through a minimum value with 1,5-diaminopentane, the best substrate of diamine oxidase of the compounds tested. The results suggest that fast substrates have less opportunity to reorient into alternate binding conformations while bound to the active site of the enzyme. On the other hand, diamine substrates tested that cannot exist in energetically favorable conformations with internitrogen distances of about 7-8 A showed larger intramolecular isotope effects.

Biosynthesis of ansatrienin by Streptomyces collinus: cell-free transformations of cyclohexene- and cyclohexadienecarboxylic acids.

Cell-free extracts of Streptomyces collinus were tested with various cyclohexene- and cyclohexadienecarboxylic acids in order to determine the latter stages of the conversion of shikimic acid to cyclohexanecarboxylic acid. It was demonstrated that the final three steps of this process involve reduction of the alpha,beta-double bond of 1(6),2-cyclohexadienylcarbonyl CoA, an isomerization of the double bond of the resulting 2-cyclohexenylcarbonyl CoA to afford 1-cyclohexenylcarbonyl CoA, and a subsequent reduction of the newly formed alpha,beta-double bond. Both of the reduction steps were shown to require NADPH as a cofactor.

The biosynthesis of monensin-A: thymine, beta-aminoisobutyrate and methacrylate metabolism in Streptomyces cinnamonensis.

Feeding experiments with isotopically labelled samples of [13C,2H3-methyl]-thymine, (R,S)-[I-13C]- and (R,S-[13C-methyl]-beta-aminoisobutyrates into monensin-A demonstrate that these metabolites can all contribute to the methylmalonyl-CoA pool in Streptomyces cinnamonensis, and implicate DNA catabolism as a contributory metabolic source of propionate carbon atoms for secondary metabolic biosynthesis. Further, these labelled compounds were unexpectedly incorporated into the butyrate unit of monensin-A, an observation which can be rationalised if beta-aminoisobutyrate is converted to methacrylyl-CoA and then reduced to isobutyryl-CoA prior to conversion to butyryl-Coa by the action of isobutyryl-CoA mutase. Feeding experiments with [I-13C]- and [13C-methyl]-methacrylates and [3-13C]-isobutyrate suggest that these metabolites partition similarly between the butyrate and propionate units of monensin-A consistent with the view that isobutyryl-CoA and methacrylyl-CoA have a close metabolic relationship.