Analysis of Legacy and Novel Neutral Per- and Polyfluoroalkyl Substances in Soils from an Industrial Manufacturing Facility.

Per- and polyfluoroalkyl substances (PFASs) have been detected in an array of environmental media due to their ubiquitous use in industrial and consumer products as well as potential release from fluorochemical manufacturing facilities. During their manufacture, many fluorotelomer (FT) facilities rely on neutral intermediates in polymer production including the FT-alcohols (FTOHs). These PFAS are known to transform to the terminal acids (perfluoro carboxylic acids; PFCAs) at rates that vary with environmental conditions. In the current study on soils from a FT facility, we employed gas chromatography coupled with conventional- and high-resolution mass spectrometry (GC-MS and GC-HRMS) to investigate the profile of these precursor compounds, the intermediary secondary alcohols (sFTOHs), FT-acrylates (FTAcr), and FT-acetates (FTAce) in soils around the former FT-production facility. Of these precursors, the general trend in detection intensity was [FTOHs] > [sFTOHs] > [FTAcrs], while for the FTOHs, homologue intensities generally were [12:2 FTOH] > [14:2 FTOH] > [16:2 FTOH] > [10:2 FTOH] > [18:2 FTOH] > [20:2 FTOH] > [8:2 FTOH] ∼ [6:2 FTOH]. The corresponding terminal acids were also detected in all soil samples and positively correlated with the precursor concentrations. GC-HRMS confirmed the presence of industrial manufacturing byproducts such as FT-ethers and FT-esters and aided in the tentative identification of previously unreported dimers and other compounds. The application of GC-HRMS to the measurement and identification of precursor PFAS is in its infancy, but the methodologies described here will help refine its use in tentatively identifying these compounds in the environment.

Double-headed small-bowel capsule endoscopy: Real-world experience from a multi-centre British study.

INTRODUCTION: Capsule endoscopy (CE) is well established the investigation of small-bowel (SB) pathology. We compared the use of double-headed (DH) capsules, to conventional single-headed (SH), in a real-world patient cohort in the first multicentre British study. METHODS: Over 9 months, patients referred for routine SBCE at 4 tertiary referral centres in the UK underwent DH CE instead of conventional SH using MiroCamⓇ MC2000 as per local protocols. One head (L/R) was chosen at random and reported by an expert reviewer. The DH recordings, anonymised and randomised, reported by another expert or re-read after a 4-week interval. For each CE, numbers and types of findings and overall conclusion/diagnosis were compared between SH and DH examinations. RESULTS: 211 CEs were performed. 7 failed to reach the SB; 204 analysed. Indications were: SB bleeding (n = 94); ?SB inflammation or reassessment of known inflammatory bowel disease (IBD) (n = 84); ?SB neoplasia including suspicious radiological imaging (n = 15); and, others e.g. ?celiac disease (n = 11). For SB bleeding: 27/94 (28.7%) examinations reported differences between SH and DH readings. In 17 (18.1%) the findings were clinically significant. SH CE missed angiectasias (5 pts), SB inflammation (7 pts), oesophagitis (2 pts) and SB masses (2 pts). In 1 patient, the extent of angiectasias seen was greater on the DH reading. For IBD: findings differed in 30/84 (35.7%) of CEs; 11 (13.1%) were clinically significant. In 5, signs of active inflammation were missed by the SH reading. In 6, assessment of extent/severity differed. For?SB neoplasia findings differed in 2/15 (13.3%) of examinations. Both were clinically significant. For others: 1/11 (9.1%) examinations differed; however, not deemed clinically significant. Overall, use of DH CE impacted the diagnosis in 30/204 (14.7%). CONCLUSIONS: The use of DH CE provides more information with the potential to change clinical diagnosis and therefore management. Therefore, the routine adoption of DH CE in SB assessment should be considered.

Repeat capsule endoscopy in suspected gastrointestinal bleeding.

Objectives: This study aims to review the utility of repeat capsule endoscopy (CE) with on-going concern of small bowel (SB) bleeding following initial SB investigation with CE. Materials and methods: A specifically designed database of CE examinations performed over 13 years, with hospital records, was retrospectively interrogated for patients undergoing multiple CEs to investigate iron deficiency anaemia (IDA) or suspected SB bleeding. Results: 1335/2276 (58.7%) of CEs were performed to investigate IDA or SB bleeding; 92 were repeat CEs carried out for ongoing clinical concern. The median time interval between initial and repeat CE procedures was 466.5 (range 1-3066) days. Twenty-four patients had initially normal CE; on repeat examination, abnormalities were detected in 11/24 (45.8%). 3/21 (14.2%) of patients with angioectasia on first CE had alternative causes for IDA or GI bleeding detected on repeat CE. Six patients with active bleeding, without an identifiable source on initial CE, undergoing repeat CE had a cause isolated in 5/6 (83.3%). Changing CE device did not affect diagnostic yield (DY) compared to repeat CE using the same device (27.5% to 26.8%). Conclusions: It is known that CE can miss clinically relevant and serious lesions. Our results suggest that patients with an initially negative or inconclusive CE frequently have a cause of SB bleeding detected on repeat CE. The DY of repeat CE is highest in those with bleeding on their initial CE (83.3%) and lower in those with initially normal examinations (45.8%) or when an alternative cause, such as angioectasia is seen (14.2%).

Haemodynamic characterisation and heart catheterisation complications in children with pulmonary hypertension: Insights from the Global TOPP Registry (tracking outcomes and practice in paediatric pulmonary hypertension).

BACKGROUND: The TOPP Registry has been designed to provide epidemiologic, diagnostic, clinical, and outcome data on children with pulmonary hypertension (PH) confirmed by heart catheterisation (HC). This study aims to identify important characteristics of the haemodynamic profile at diagnosis and HC complications of paediatric patients presenting with PH. METHODS AND RESULTS: HC data sets underwent a blinded review for confirmation of PH (defined as mean pulmonary arterial pressure ≥ 25 mmHg, pulmonary capillary wedge pressure ≤ 12 mmHg and pulmonary vascular resistance index [PVRI] of >3 WU × m(2)). Of 568 patients enrolled, 472 who fulfilled the inclusion criteria and had sufficient data from HC were analysed. A total of 908 diagnostic and follow-up HCs were performed and complications occurred in 5.9% of all HCs including five (0.6%) deaths. General anaesthesia (GA) was used in 53%, and conscious sedation in 47%. Complications at diagnosis were more likely to occur if GA was used (p=0.04) and with higher functional class (p=0.02). Mean cardiac index (CI) was within normal limits at diagnosis when analysed for the entire group (3.7 L/min/m(2); 95% confidence interval 3.4-4.1), as was right atrial pressure despite a severely increased PVRI (16.6 WU × m(2,) 95% confidence interval 15.6-17.76). However, 24% of the patients had a CI of <2.5L/min/m(2) at diagnosis. A progressive increase in PVRI and decrease in CI was observed with age (p<0.001). CONCLUSION: In TOPP, haemodynamic assessment was remarkable for preserved CI in the majority of patients despite severely elevated PVRI. HC-related complication incidence was 5.9%, and was associated with GA and higher functional class.

A study of aspirin and clopidogrel in idiopathic pulmonary arterial hypertension.

Idiopathic pulmonary arterial hypertension (IPAH) is characterised by in situ thrombosis and increased thromboxane (Tx) A2 synthesis; however, there are no studies of antiplatelet therapy in IPAH. The aim of the current study was to determine the biochemical effects of aspirin (ASA) and clopidogrel on platelet function and eicosanoid metabolism in patients with IPAH. A randomised, double-blind, placebo-controlled crossover study of ASA 81 mg once daily and clopidogrel 75 mg once daily was performed. Plasma P-selectin levels and aggregometry were measured after exposure to adenosine diphosphate, arachidonic acid and collagen. Serum levels of TxB2 and urinary metabolites of TxA2 and prostaglandin I2 (Tx-M and PGI-M, respectively) were assessed. A total of 19 IPAH patients were enrolled, of whom nine were being treated with continuous intravenous epoprostenol. ASA and clopidogrel significantly reduced platelet aggregation to arachidonic acid and adenosine diphosphate, respectively. ASA significantly decreased serum TxB2, urinary Tx-M levels and the Tx-M/PGI-M ratio, whereas clopidogrel had no effect on eicosanoid levels. Neither drug significantly lowered plasma P-selectin levels. Epoprostenol use did not affect the results. In conclusion, aspirin and clopidogrel inhibited platelet aggregation, and aspirin reduced thromboxane metabolite production without affecting prostaglandin I2 metabolite synthesis. Further clinical trials of aspirin in patients with idiopathic pulmonary arterial hypertension should be performed.

Attenuated expression of the mga virulence regulon in an M serotype 50 mouse-virulent group A streptococcal strain.

The attenuated expression of virulence genes found in a group A streptococcal strain that is naturally pathogenic for mice was postulated to result from a defect in the strain's multigene regulator, Mga. The sequence of the mga gene reveals three amino acid changes in the gene product that might affect protein function. The defect in the mga gene was complemented by providing either the closely similar mga4 allele or a more divergent mga1 allele in trans. Complementation increased the amount of emm50 transcript and the quantity of surface-extractable M protein, restoring virulence function.

Role of putative virulence factors of Streptococcus pyogenes in mouse models of long-term throat colonization and pneumonia.

To investigate the role of putative virulence factors of Streptococcus pyogenes (group A streptococcus; GAS) in causing disease, we introduced specific mutations in GAS strain B514, a natural mouse pathogen, and tested the mutant strains in two models of infection. To study late stages of disease, we used our previously described mouse model (C3HeB/FeJ mice) in which pneumonia and systemic spread of the streptococcus follow intratracheal inoculation. To study the early stages of disease, we report here a model of long-term (at least 21 days) throat colonization following intranasal inoculation of C57BL/10SnJ mice. When the three emm family genes of GAS strain B514-Sm were deleted, the mutant showed no significant difference from the wild type in induction of long-term throat colonization or pneumonia. We inactivated the scpA gene, which encodes a complement C5a peptidase, by insertion of a nonreplicative plasmid and found no significant difference from the wild type in the incidence of throat colonization. However, there was a small but statistically significant decrease in the incidence of pneumonia caused by the scpA mutant. Finally, we demonstrated a very important effect of the hyaluronic acid capsule in both models. Following intranasal inoculation of mice with a mutant in which a nonreplicative plasmid was inserted into the hasA gene, which encodes hyaluronate synthase, we found that all bacteria recovered from the throats of the mice were encapsulated revertants. Following intratracheal inoculation with the hasA mutant, the incidence of pneumonia within 72 h was significantly reduced from that of the control strain (P = 0.006). These results indicate that the hyaluronic acid capsule of S. pyogenes B514 confers an important selective advantage for survival of the bacteria in the upper respiratory tract and is also an important determinant in induction of pneumonia in our model system.

DNA sequencing and gene expression of the emm gene cluster in an M50 group A streptococcus strain virulent for mice.

The strain B514, an M serotype 50 strain, is capable of causing a natural upper respiratory infection leading to death in mice, as reported by Hook et al. in 1960 (E. W. Hook, R. R. Wagner, and R. C. Lancefield, Am. J. Hyg. 72:111-119, 1960). Thus, this strain was of interest for use in developing an animal model for group A streptococcal colonization and disease. The emm gene cluster for this strain was examined by PCR mapping and found to contain three emm family genes and cluster pattern 5. PCR-generated fragments corresponding to the SF4 (mrp50), SF2 (emmL50), and SF3 (enn50) genes were cloned and the entire gene cluster was sequenced. The gene cluster has greater than 97% DNA identity to previously sequenced regions of the gene cluster of the M2 strain T2/44/RB4 if two small divergent regions that encode the mature amino terminus of the SF-2 and SF-3 gene products are not included. If expressed, the genes encode proteins which bind human immunoglobulin G (Mrp50 and EmmL50) or immunoglobulin A (Enn50). However, in isolates taken directly after passage in mice, the surface proteins arising from these genes were barely detectable. The transcription of each gene in the B514 strain was investigated by Northern (RNA) hybridization, and mRNA transcripts were detected and quantitated relative to those of the recA gene, a housekeeping gene. Transcription of all three emm family genes was found to be over 30-fold attenuated relative to transcription of the same genes in strain T2/44/RB4. This suggests that the positive regulator, Mga, either is not expressed in this strain or has a different requirement for activation; it also suggests that the capsule may be sufficient to inhibit phagocytosis under these circumstances.

Structural heterogeneity of the emm gene cluster in group A streptococci.

One or more distinct copies of emm genes lie within a gene cluster that is located downstream from a transcriptional regulatory gene (mry). Mry is a positive regulator for the genes in this cluster and for the downstream gene, scpA. The objective of this study is to examine the structure of this cluster and the distribution of specific alleles within the cluster among group A streptococcal isolates of 32 different serotypes. The peptidoglycan (PG)-spanning domain, which exists in four divergent forms, was used to identify specific alleles of the genes within the emm cluster. Gene content of the cluster was determined by Southern hybridization with allele-specific oligonucleotides. Five different chromosomal patterns for this cluster were observed. Sequence heterogeneity in the adjacent mry locus was demonstrated by the ability of some of the isolates to hybridize with a whole mry gene probe, but not with mry-based oligonucleotide probes. A PCR-based chromosomal mapping technique was used to examine further the gene order within the emm gene clusters. Structural heterogeneity of the emm gene cluster was found within class I isolates in this study, while class II isolates were relatively homogeneous at this chromosomal locus and distinct from class I.

Characterization of pharmacy workload and pharmacist activities in a Canadian community pharmacy.

The present study was undertaken to obtain data which would characterize pharmacist activities and prescription workload in a community pharmacy. Data on pharmacist activities were obtained by using a work sampling methodology. The proportion of time spent on each of 44 activities was obtained, and it was found that the proportion of time spent on professional activities (17.6 percent) was notably less than the time spent on nonprofessional activities (82.4 percent). Data on prescription workload were obtained by the design of a data sheet which was to be completed by each pharmacist for every prescription dispensed. The collected data characterized the number of prescriptions dispensed, which were related to the time of day and day of the week; they also provided information on the types of prescriptions dispensed, the age of patients (e.g., pediatric, geriatric), and the methods of payment.

Synthesis and quantitative structure--activity relationships of some antibacterial 3-formylrifamycin SV N-(4-substituted phenyl)piperazinoacethydrazones.

A series of 14 3-formylrifamycin SV N-(4-substituted phenyl)piperazinoacethydrazones has been synthesized and evaluated for their antimicrobial activity. The compounds were found active against Bacillus subtilis, Staphylococcus aureus, Mycobacterium phlei, and Mycobacterium tuberculosis but not as active as rifampin. The compounds also exhibited significant activity against Clostridium perfringens and in this bacterial system some were more active than rifampin. The QSAR showed that the activity against B. subtilis depended only on lipophilicity, and the regression equation was linear. A parabolic relationship between the antibacterial activity and lipophilicity of the compounds was found in Staph. aureus. Additionally, the activity was dependent upon the electronic and steric effects of the phenyl substituents. The sensitivity of M. phlei to the compounds was found to correlate well with a linear combination of hydrophobic, electronic, and steric parameters. No statistically significant correlation was possible between the physicochemical parameters studied and the activity of the compounds against C. perfringens and M. tuberculosis.

Synthesis and quantitative structure-activity relationships of antibacterial 1-(substituted benzhydryl)-4-(5-nitro-2-furfurylideneamino) piperazines.

1-Benzhydryl -4- (5-nitro-2-furfurylideneamino) piperazine and 11 substituted analogs were prepared and examined for in vitro antimicrobial activity. The compounds were active against Bacillus cereus 7, Bacillus megaterium 122, Bacillus subtilis 104, Clostridium perfringens 13, and the tetracycline-resistant Clostridium perfringens 37. Regression analyses on the antibacterial activity data based on the Hansch approach, using pi, pi2, and sigma parameters, yielded several statistically significant correlation equations. 1-Benzhydryl-4-(5-nitro-2-furfurylideneamino) piperazine stopped the protein and DNA syntheses in C. perfringens 13, as indicated by precipitable radioactivity. The compound, however, showed no effect on the cell wall synthesis in the bacteria.

Reactions of benzenesulfonohydrazides and benzenesulfonamides with hydrogen chloride or hydrogen bromide in acetic acid.

Benzenesulfonohydrazides capable of yielding a sulfinic acid intermediate by virtue of a basic nitrogen atom in the second position of the hydrazide moiety produced thiosulfonates when treated with 1 N hydrogen chloride in acetic acid and produced disulfides when treated with 1 N hydrogen bromide in the same solvent. In two cases, a crystalline mixture of P-nitrophenyl p-nitrobenzenethiosulfonate and bis(p-nitrophenyl) disulfide was isolated from the hydrogen chloride reactions. No reaction product was obtained from either the hydrogen chloride or hydrogen bromide reaction with benzenesulfonohydrazides that were unable to form a sulfinic acid intermediate. Reduction of benzenesulfonamides to disulfides appeared to be possible only with hydrogen bromide in acetic acid. No thiosulfonate was isolated from the treatments of benzenesulfonamides with 1 N hydrogen chloride in acetic acid. p-Nitrophenyl p-nitrobenzenethiosulfonate and p-bromophenyl p-bromobenzenethiosulfonate exhibited some antimicrobial activities against Gram-positive bacteria. The latter compound also showed analgesic properties in the phenylquinone test.