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51.

Background

Carbon monoxide (CO) is formed as a result of the incomplete burning of hydrocarbon-containing fuels such as natural gas, coal, liquid petroleum gas, and wood. CO is a colorless, odorless, and poisonous gas that produces various acute and chronic effects in CO-exposed people. In this study, we aimed to measure CO levels in auto care repairmen with chronic CO-related illnesses using a serial, non-invasive method.A prospective cohort study.

Methods

A total of 99 people from six different auto-repair services were included in the study. Carboxyhemoglobin (COHb) levels were measured at four different times with 2-hour intervals starting at 08:00 AM. Data concerning employees’ ages, working hours, smoking statuses, and types of home heating fuel were collected. A control group of 100 cases was created based on this data. The measurements were done on the control group in the morning with a Masimo Rad-57 CO-oximeter.

Results

The highest mean (± SD) COHb value was 7.04%?±?3.32% after the third measurement. The mean value for the control group was 1.61%?±?1.43%. A statistically significant difference between the groups was found for each value.

Discussion

We determined that the risk of being affected by CO is high in buildings in which the auto services were located. The effects of chronic or prolonged exposure to low amounts of CO were found to be ambiguous. However, in some studies, it was found that low-grade CO exposure could lead to coronary artery disease and some neurological complications. Therefore, it is necessary to be careful about the health of employees who have been exposed to CO.

Conclusions

We concluded that there is a need for more detailed studies concerning chronic CO poisoning. Also, in workplaces in which there is high exposure to CO, proper workplace safety measures should be taken to reduce this gas’s harmful effects to employees.
  相似文献   
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The spread of antimicrobial resistance challenges the empirical treatment of urinary tract infections (UTIs). Among others, nitrofurantoin is recommended for first-line treatment, but acceptance among clinicians is limited due to chronic nitrofurantoin-induced lung toxicity and insufficient coverage of Enterobacteriaceae other than Escherichia coli. Nitroxoline appears to be an alternative to nitrofurantoin owing to its favourable safety profile, however data on its current in vitro susceptibility are sparse. In this study, susceptibility to nitroxoline was tested against 3012 urinary clinical isolates (including multidrug-resistant bacteria and Candida spp.) by disk diffusion test and/or broth microdilution. At least 91% of all Gram-negatives (n?=?2000), Gram-positives (n?=?403) and yeasts (n?=?132) had inhibition zone diameters for nitroxoline ≥18?mm. Except for Pseudomonas aeruginosa, nitroxoline MIC90 values were ≤16?mg/L and were 2- to >16-fold lower compared with nitrofurantoin. In extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae and methicillin-resistant Staphylococcus aureus (MRSA), MIC90 values of nitroxoline were two-fold higher compared with non-ESBL-producing enterobacteria and methicillin-susceptible S. aureus (MSSA). The in vitro efficacies of nitroxoline and nitrofurantoin against ATCC strains of E. coli, Enterococcus faecalis and Proteus mirabilis were compared by time–kill curves in Mueller–Hinton broth and artificial urine. Nitroxoline was non-inferior against E. coli, P. mirabilis and E. faecalis in artificial urine. In conclusion, nitroxoline showed a broad antimicrobial spectrum, with inhibition zone diameters and MICs of nitroxoline well below the EUCAST breakpoint for E. coli for most organisms, and thus may also be a target for therapy of uncomplicated UTIs.  相似文献   
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The interaction of trolox with ammonia, alkylamines of different classes, and amino derivatives of heterocyclic compounds, including nitroxyl radicals and alkaloids, led to the production of ammonium salts called ion conjugates (ICs). Five ICs were characterised by X-ray diffraction. This is the first time a wide range of ICs were made from trolox with amines, and ESI-MS data demonstrated they have the potential to generate pseudomolecular [(A?B+)?+?H]+ ions. For all obtained trolox ICs, a significant increase (1–3 orders of magnitude) in water solubility was achieved while retaining high antioxidant activity. ICs synthesised from two biologically active fragments may be used to create polyfunctional agents with varying solubility and bioavailability.  相似文献   
56.
Extracellular vesicles (EV) are secreted signaling entities that enhance various pathological processes when released in response to cellular stresses. Respiratory exposures such as cigarette smoke and air pollution exert cellular stresses and are associated with an increased risk of several chronic diseases. The aim of this review was to examine the evidence that modifications in EV contribute to respiratory exposure-associated diseases. Publications were searched using PubMed and Google Scholar with the search terms (cigarette smoke OR tobacco smoke OR air pollution OR particulate matter) AND (extracellular vesicles OR exosomes OR microvesicles OR microparticles OR ectosomes). All original research articles were included and reviewed. Fifty articles were identified, most of which investigated the effect of respiratory exposures on EV release in vitro (25) and/or on circulating EV in human plasma (24). The majority of studies based their main observations on the relatively insensitive scatter-based flow cytometry of EV (29). EV induced by respiratory exposures were found to modulate inflammation (19), thrombosis (13), endothelial dysfunction (11), tissue remodeling (6), and angiogenesis (3). By influencing these processes, EV may play a key role in the development of cardiovascular diseases and chronic obstructive pulmonary disease and possibly lung cancer and allergic asthma. The current findings warrant additional research with improved methodologies to evaluate the contribution of respiratory exposure-induced EV to disease etiology, as well as their potential as biomarkers of exposure or risk and as novel targets for preventive or therapeutic strategies.  相似文献   
57.
Historically, no black fly (Diptera: Simuliidae) nuisance has been reported in the Murcia Region. Back in September 2016 the Ojós City Council has contacted the Regional Public Health General Directorate for help regarding a local insect nuisance, most probably based on mosquitoes. After sampling with a BG-sentinel 2 trap, collecting adult specimens with an entomological aspirator, and collect larvae and pupae on submerged giant cane stalks at the river, it turned out that Simulium sergenti was the insect species causing the nuisance. This species is not considered particularly anthropophilic; therefore, a low vector risk for human health was considered. However, the high fly density impaired the life quality of the people at the village. A management plan was recommended, treating the river with Bacillus thuringiensis var israelensis.  相似文献   
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Purpose

To conduct a systematic literature review of the reliability, construct validity, and responsiveness of the SF-36® Health Survey (SF-36) in patients with ulcerative colitis (UC).

Methods

We performed a systematic search of electronic medical databases to identify published peer-reviewed studies which reported scores from the eight scales and/or two summary measures of the SF-36 collected from adult patients with UC. Study findings relevant to reliability, construct validity, and responsiveness were reviewed.

Results

Data were extracted and summarized from 43 articles meeting inclusion criteria. Convergent validity was supported by findings that 83% (197/236) of correlations between SF-36 scales and measures of disease symptoms, disease activity, and functioning exceeded the prespecified threshold (r ≥ |0.40|). Known-groups validity was supported by findings of clinically meaningful differences in SF-36 scores between subgroups of patients when classified by disease activity (i.e., active versus inactive), symptom status, and comorbidity status. Responsiveness was supported by findings of clinically meaningful changes in SF-36 scores following treatment in non-comparative trials, and by meaningfully larger improvements in SF-36 scores in treatment arms relative to controls in randomized controlled trials. The sole study of SF-36 reliability found evidence supporting internal consistency (Cronbach’s α ≥ 0.70) for all SF-36 scales and test–retest reliability (intraclass correlation coefficient ≥0.70) for six of eight scales.

Conclusions

Evidence from this systematic literature review indicates that the SF-36 is reliable, valid, and responsive when used with UC patients, supporting the inclusion of the SF-36 as an endpoint in clinical trials for this patient population.
  相似文献   
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