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Direct evidence on the impact of air pollution on preterm birth (PTB) among advanced maternal age (AMA) primiparas is limited. This study examined the association between air pollution and PTB among 6,295 AMA primiparas in rural Henan Province. Logistic regression and distributed lag nonlinear models showed that prenatal exposure to carbon monoxide (CO), sulfur dioxide (SO2), nitrogen dioxide (NO2), and fine particulate matter (PM2.5) was associated with an increased PTB risk among AMA primiparas, while ozone (O3) exposure was inversely related to PTB risk (all P < 0.05). Moreover, the vulnerable periods were identified as gestational weeks 1–6 and 22–28. The education level, smoking status, and season of conception significantly modified the association between PTB and air pollution (P interaction < 0.10) among AMA primiparas. These findings emphasize the impact of air pollution on PTB risk in AMA primiparas, highlighting the need for targeted interventions in vulnerable populations. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 38-year-old woman with methemoglobinemia and hypoxemic respiratory failure, focusing on the discrepancy between pulse oximetry (SpO2) and arterial blood gas (SaO2) readings. Topics discussed include noninvasive oxygen measurement via pulse oximetry, the impact of methemoglobinemia on oxygen delivery, and the differential diagnosis for an "SpO2–SaO2 gap."

Rationale: Cannabis use is rapidly growing in the United States, but its health implications are poorly understood, particularly when compared with cigarette smoking. Previous research conducted on animal models or nonrepresentative populations with small sample sizes has yielded mixed results on the impact of marijuana use on hemoglobin concentrations, which might reflect subclinical hypoxemia and/or carbon monoxide exposure. Objectives: We evaluated the association between marijuana use and hemoglobin concentrations in a nationally representative sample of U.S. adults. Methods: This cross-sectional study included 16,038 individuals 18–59 years of age enrolled in National Health and Nutrition Examination Survey (NHANES) from 2009 to 2018. We related current and former marijuana use with measured hemoglobin concentrations, with adjustment for demographics, education, housing, and cigarette smoking status in multivariable analyses that incorporated complex survey weights. As candidate positive and negative control exposures, we used similar methods to relate cigarette smoking and benzodiazepine use, respectively, with hemoglobin concentrations. Results: Current marijuana use was associated with significantly higher hemoglobin concentrations. After multivariable adjustment, compared with never use, current marijuana use was associated with a 0.111 (95% confidence interval, 0.021 to 0.201) g/dl higher hemoglobin concentration, whereas former use was associated with a 0.047 (95% confidence interval, −0.018 to 0.113) g/dl higher concentration (linear trend P = 0.01). As hypothesized, cigarette smoking was also associated with higher hemoglobin concentrations, whereas benzodiazepine use was not. Conclusions: Among American adults, current marijuana use was associated with higher hemoglobin concentrations, as is cigarette smoking but not benzodiazepine use. These results suggest the possibility that marijuana smoking induces subclinical hypoxemia stimulating hemoglobin production. Further confirmation of this observational finding is needed in light of the increasing medical and recreational use of smoked marijuana products. [ABSTRACT FROM AUTHOR]

Acute carbon monoxide (CO) poisoning may cause liver damage and liver dysfunction. Therefore, in this study, we aimed to compare the efficiency of normobaric oxygen (NBO) and high-flow nasal cannula oxygen (HFNCO) treatments on liver injury. For that purpose, 28 male Wistar albino rats were divided into four groups (Control, CO, CO + NBO, and CO + HFNCO). The control group was allowed to breath room air for 30 min. Acute CO poisoning in CO, CO + NBO, CO + HFNCO was induced by CO exposure for 30 min. Thereafter, NBO group received 100% NBO with reservoir mask for 30 min. HFNCO group received high-flow oxygen through nasal cannula for 30 min. At the end of the experiment, all animals were sacrificed by cardiac puncture under anesthesia. Serum liver function tests were measured. Liver tissue total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) levels, tissue histomorphology and immunoexpression levels of Bax, Caspase 3, TNF-α, IL-1β, and NF-κB were also examined. Our observations indicated that acute CO poisoning caused significant increases in blood COHb, serum aminotransferase (AST), alanine aminotransferase (ALT0, alkaline phosphatase (ALP), total protein, albumin, and globulin levels but a decrease in albumin to globulin ratio (all, p < 0.05). Furthermore, acute CO poisoning significantly increased the OSI value, and the immunoexpresssion of Bax, Caspase 3, TNF-α, IL-1β, and NF-κB in liver tissue (all, p < 0.05). These pathological changes in serum and liver tissue were alleviated through both of the treatment methods. In conclusion, both the NBO and HFNCO treatments were beneficial to alleviate the acute CO poisoning associated with liver injury and dysfunction. Twenty-eight rats were divided into four groups (control, CO, CO + NBO, and CO + HFNCO) and the animals in CO, CO + NBO, CO + HFNCO were exposed to CO poisoning in a closed box (1), CO + NBO group received 100% normobaric oxygen with a reservoir mask at a flow rate 15 L/min (2), CO + HFNCO group received high-flow oxygen through nasal cannula at a flow rate of 60 L/min (3). All rats were sacrificed by cardiac puncture under anesthesia (4), blood and liver tissues were received (5) for the laboratory examinations (6). Our observations indicated that CO poisoning (7) caused significant increases in blood COHb, serum AST, ALT, ALP, total protein, albumin, globulin levels but a decrease in albumin to globulin ratio as well as the upregulation of tissue oxidative stress, and inflammatory cytokine levels (8). The upregulated oxidative stress and inflammation possibly led to increases in apoptotic protein expressions of Bax (9), Caspase 3, and NF-κB (10). The elevated NF-κB potentially increased the pro-inflammatory cytokine levels (11). However, both O2 treatments alleviated the pathological alterations in both serum and liver tissue (12). [ABSTRACT FROM AUTHOR]

• Carboxyhemoglobin (CO-Hb) was reported to likely reflect hemolysis and inflammation, both risk factors for cardiac surgery–associated acute kidney injury (CSA-AKI). • CO-Hb is easily obtainable and available on routine blood gas in cardiac surgery patients at no additional costs or equipment. • Patients with CO-Hb ≥1.4% at intensive care unit admission showed a significantly higher rate of CSA-AKI. • CO-Hb at intensive care unit admission may serve as a practical and biologically logical biomarker in both clinical and research settings. • Specifically for research purposes, CO-Hb could be used for risk stratification and population enrichment in trials of CSA-AKI prevention to increase statistical power, decrease the sample size, and lower the cost of trials. Carboxyhemoglobin (CO-Hb) is a marker of hemolysis and inflammation, both risk factors for cardiac surgery–associated AKI (CSA-AKI). However, the association between CO-Hb and CSA-AKI remains unknown. A retrospective cohort study. Tertiary university-affiliated metropolitan hospital: single center. Adult on-pump cardiac surgery patients from July 2014 to June 2022 (N = 1,698). None. Patients were stratified into quartiles based on CO-Hb levels at intensive care unit (ICU) admission. A progressive increased risk of CSA-AKI was observed with higher CO-Hb levels at ICU admission. On multivariable logistic regression analysis, the highest quartile (CO-Hb ≥ 1.4%) showed an independent association with the occurrence of CSA-AKI (odds ratio 1.45 compared to the lowest quartile [CO-Hb < 1.0%], 95% CI 1.023-2.071; p = 0.038). Compared to patients with CO-Hb <1.4%, patients with CO-Hb ≥ 1.4% at ICU admission had significantly higher postoperative creatinine (135 vs 116 μmol/L, p < 0.001), higher rates of postoperative RRT (6.7% vs 2.3%, p < 0.001) and AKI (p < 0.001) on univariable analysis and shorter time to event for AKI or death (p < 0.001). CO-Hb ≥ 1.4% at ICU admission is an independent risk factor for CSA-AKI, which is easily obtainable and available on routine arterial blood gas measurements. Thus, CO-Hb may serve as a practical and biologically logical biomarker for risk stratification and population enrichment in trials of CSA-AKI prevention. [ABSTRACT FROM AUTHOR]

Background: Carbon monoxide (CO) poisoning is a major health problem associated with a high rate of severe morbidity and mortality. Aims: This study aimed to evaluate the validity of the serum glucose/potassium (Glu/K) ratio as a quick predictor of both early and delayed unfavorable outcomes following acute CO poisoning. Patients and methods: This prospective cohort study included 136 patients with acute CO poisoning admitted at Tanta Poison Control Center, Egypt, between January 2023 and June 2024. The serum Glu/K ratio was calculated for all patients. The primary outcome was a prediction of mortality. Secondary outcomes were the prediction of delayed neurological sequelae (DNS) within six months after CO exposure, the need for mechanical ventilation, and the need for hyperbaric oxygen. A receiver operating curve analysis was applied to test the performance of the Glu/K ratio in predicting acute CO poisoning outcomes. Results: The mortality rate was 12.5% of patients with acute CO poisoning. Meanwhile, 14.7% of patients developed DNS. Furthermore, mechanical ventilation was required in 16.9% of patients. An elevated Glu/K ratio was significantly associated with the severity of acute CO poisoning. At a cut-off value of >31.62, the Glu/K ratio demonstrated an AUC of 0.649 for predicting mortality. The Glu/K ratio was employed to predict DNS at a cut-off value of 33.10, with a sensitivity of 60.0%, a specificity of 82.76%, and an AUC of 0.692. Conclusions: Early Glu/K ratio may be an effective, reliable, and convenient laboratory predictor of mortality, DNS, and the need for mechanical ventilation in patients with acute CO poisoning. [ABSTRACT FROM AUTHOR]

Aim: Hookah smoking is increasing all over the world, and it can cause many health problems that are rarely known to be experienced by smokers. The aim of this study was to evaluate the acute impact of hookah smoking on hemodynamic parameters using perfusion index (PI) and pleth variability index (PVI). Materials and Methods: This prospective observational study was conducted in a hookah cafe with 84 participants. Systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse, oxygen saturation (SpO2), carboxyhemoglobin (COHb) PI, and PVI values of the participants were measured immediately before and 30 min after hookah smoking. Results: Sixty-three (75%) participants were male, and the median age was 26 [interquartile range (IQR) 22-29]. There were no significant changes in SBP, DBP, pulse, and SpO2 following hookah smoking. There was a 2% (IQR 2-3) increase in COHb level (p

Jiwoong Her,1,2 Justin Roh,1 Deborah A Keys3 1Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, USA; 2Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA; 3Kaleidoscope Statistics, LLC Athens, GA, USACorrespondence: Jiwoong Her, Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA, Email Jiwoong.her@outlook.comPurpose: To assess the agreement between pulse co-oximeter and blood co-oximeter in measuring methemoglobin (MetHb) and carboxyhemoglobin (COHb) in healthy, awake dogs.Patients and Methods: Forty-five healthy dogs were enrolled in the study. Pulse co-oximetry was performed using the Masimo Radical 7 Pulse Co-Oximeter with a Rainbow® adhesive sensor. Simultaneously, venous blood samples were collected, and MetHb and COHb were immediately measured using a Stat Profile Prime Plus VET Critical Care Analyzer. Paired measurements of MetHb and COHb were evaluated via Spearman correlation, intra-class correlation (ICC), and Bland-Altman plots to evaluate the degree of agreement between the pulse co-oximeter and the blood co-oximeter.Results: A total of 45 paired MetHb and COHb measurements were collected. There was a weak correlation between the pulse co-oximeter and the blood co-oximeter readings. The correlation coefficients for MetHb and COHb were 0.0 (95% CI, − 0.3 to 0.3) and 0.03 (95% CI, − 0.27 to 0.32), respectively. The ICC indicated poor agreement between the pulse and blood co-oximeter for MetHb (ICC = 0.00, 95% CI: − 0.12 to 0.15) and COHb (ICC = 0.03, 95% CI: − 0.27 to 0.33). Bland-Altman plots revealed low mean bias but wide limits of agreement, indicating that the pulse co-oximeter overestimated MetHb by on average of 0.7% (P < 0.0001) (95% LoA: − 0.5 to 2.0) and COHb by on average 0.2% (P = 0.59) (95% LoA: − 4.6 to 5.0).Conclusion: Obtaining MetHb and COHb measurements with the Masimo Radical 7 Pulse Co-Oximeter is straightforward in healthy, awake dogs. However, the device does not provide accurate measurements compared to the blood co-oximeter, specifically in the range of MetHb and COHb in healthy dogs, based on the wide LoA.Keywords: co-oximetry, methemoglobin, carboxyhemoglobin, dog

Proton exchange membrane fuel cells (PEMFCs), as a feasible alternative to replace the traditional fossil fuel-based energy converter, contribute significantly to the global sustainability agenda. At the PEMFC anode, given the high exchange current density, Pt/C is deemed the catalyst-of-choice to ensure that the hydrogen oxidation reaction (HOR) occurs at a sufficiently fast pace. The high performance of Pt/C, however, can only be achieved under the premise that high purity hydrogen is used. For instance, in the presence of trace level carbon monoxide, a typical contaminant during H2 production, Pt is severely deactivated by CO surface blockage. Addressing the poisoning issue necessitates for either developing anti-poisoning electrocatalysts or using pre-purified H2 obtained via a thermo-catalysis route. In other words, the CO poisoning issue can be addressed by either thermal-catalysis from the H2 supply side or electrocatalysis at the user side, respectively. In spite of the distinction between thermo-catalysis and electro-catalysis, there are high similarities between the two routes. Essentially, a reduction in the kinetic barrier for the combination of CO to oxygen containing intermediates is required in both techniques. Therefore, bridging electrocatalysis and thermocatalysis might offer new insight into the development of cutting edge catalysts to solve the poisoning issue, which, however, stands as an underexplored frontier in catalysis science. This review provides a critical appraisal of the recent advancements in preferential CO oxidation (CO-PROX) thermocatalysts and anti-poisoning HOR electrocatalysts, aiming to bridge the gap in cognition between the two routes. First, we discuss the differences in thermal/electrocatalysis, CO oxidation mechanisms, and anti-CO poisoning strategies. Second, we comprehensively summarize the progress of supported and unsupported CO-tolerant catalysts based on the timeline of development (nanoparticles to clusters to single atoms), focusing on metal–support interactions and interface reactivity. Third, we elucidate the stability issue and theoretical understanding of CO-tolerant electrocatalysts, which are critical factors for the rational design of high-performance catalysts. Finally, we underscore the imminent challenges in bridging thermal/electrocatalytic CO oxidation, with theory, materials, and the mechanism as the three main weapons to gain a more in-depth understanding. We anticipate that this review will contribute to the cognition of both thermocatalysis and electrocatalysis. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effects of contamination of venous blood with a lipid-containing solution on parameters measured by a modern blood gas analyzer. We collected venous blood from 17 healthcare workers (46 ± 11 years; 53 % women) into three blood gas syringes containing 0 , 5 and 10 % lipid-containing solution. Blood gas analysis was performed within 15 min from sample collection on GEM Premier 5000, while triglycerides and serum indices were assays on Roche COBAS C702. Triglycerides concentration increased from 1.0 ± 0.3 mmol/L in the uncontaminated blood gas syringe, to 39.4 ± 7.8 and 65.3 ± 14.4 mmol/L (both p<0.001) in syringes with 5 and 10 % final lipid contamination. The lipemic and hemolysis indices increased accordingly. Statistically significant variation was noted for all analytes except hematocrit and COHb in the syringe with 5 % lipids, while only COHb did not vary in the syringe with 10 % lipids. Significant increases were observed from 5 % lipid contamination for pO2, SO2 and lactate, while the values of pH, pCO2, sodium, potassium, chloride, ionized calcium, glucose, hematocrit (10 % contamination), hemoglobin and MetHB decreased. All these changes except lactate and CoHb exceeded their relative performance specifications. Artifactual hyperlipidemia caused by contamination with exogenous lipids can have a clinically significant impact on blood gas analysis. Manufacturers of blood gas analyzers must be persuaded to develop new instruments equipped with serum indices. [ABSTRACT FROM AUTHOR]

A novel pulsed power source capable of nanosecond pulses with burst frequencies up to 1 MHz is employed to create atmospheric pressure pulsed plasma in pure CO2 gas. The short bursts contain up to four nanosecond pulses. The CO2 conversion and corresponding energy efficiency are measured ex-situ with Fourier-transform infrared absorption spectroscopy. Trends in the absorption line profile of in-situ quantum cascade laser infrared absorption spectroscopy indicate an elevated vibrational temperature of CO2 with an increasing number of pulses per burst. The key result of this paper is that the dissociation energy efficiency is higher when operating the plasma in burst mode. Furthermore, a larger number of pulses in a burst is associated with a further increase of the dissociation efficiency. The highest efficiency measured is (17.7 ± 0.3) % for single pulses spaced 2 ms apart, and (20.0 ± 0.3) % for bursts of three pulses, with an in-burst frequency of 1 MHz and bursts spaced 4 ms apart. [ABSTRACT FROM AUTHOR]

Gaseous signaling molecules (GSMs) including nitric oxide (NO), carbon monoxide (CO) and hydrogen sulfide (H2S) have presented excellent therapeutic efficacy such as anti‐inflammatory, anti‐microbial and anti‐cancer effects and multiple biomedical applications in recent years. As the three most vital signaling molecules in human physiology, these three GSMs show so intertwined and orchestrated interactions that the synergy of multiple gases may demonstrate a more complex therapeutic potential than single gas delivery. Consequently, researchers have been devoted to developing codelivery systems of GSMs by synthesizing a single molecule as a dual donor to maximize the gaseous therapeutic efficacy. In this minireview, we summarize the recent developments of molecules or materials enabling codelivery of GSMs for biomedical applications. It appears that compared with the abundant cases of codelivery of NO and H2S, research on codelivery of CO and the other two GSMs separately remains to be explored. [ABSTRACT FROM AUTHOR]

Objective: Electrocautery in laparoscopic surgeries converts abdominal carbon dioxide gas into carbon monoxide, which binds to hemoglobin with a higher affinity than oxygen and can impair oxygen transport and lead to hypoxia. This study aimed to assess changes in carboxyhemoglobin (COHb) levels and investigate the factors affecting COHb levels in patients undergoing robotic surgery. Methods: Forty-two patients were included in this retrospective study. Patient demographics, anesthetic used, airway pressures, and COHb levels at different time points (baseline COHb-1st hour COHb-post-pneumoperitoneum COHb-postoperative care unit COHb-deltaCOHb) were considered. Age, gender, American Society of Anesthesiology (ASA) physical score, body mass index, smoking status, surgery type, anesthesia type, patient position, fresh gas flow (FGF), insufflation, and airway pressures, which may have an effect on COHb levels, were compared. Results: No significant relationship was found between COHb levels at all measured time points and factors such as gender, ASA scores, surgery type, anesthesia type, position, FGF, insufflation pressure, and airway pressure. Smokers had significantly higher COHb levels than passive smokers, non-smokers, and ex-smokers at baseline (p=0.003), 1st hour (p=0.006), and post-pneumoperitoneum COHb (p=0.009) levels. Conclusion: Long surgery time, use of different types of anesthetics, and low FGF does not increase the risk of elevated COHb levels. Hence, different anesthetic drugs and low FGF, regardless of the position of the patient or the length of the procedure, can be used in robotic surgery without increasing the risk. [ABSTRACT FROM AUTHOR]

Delayed neuropsychiatric sequelae (DNS) are critical complications following acute carbon monoxide (CO) poisoning that can substantially affect the patient's life. Identifying high-risk patients for developing DNS may improve the quality of follow-up care. To date, the predictive DNS determinants are still controversial. Consequently, this study aimed to construct a practical nomogram for predicting DNS in acute CO-poisoned patients. This retrospective study was conducted on patients with acute CO poisoning admitted to the Tanta University Poison Control Center (TUPCC) from December 2018 to December 2022. Demographic, toxicological, and initial clinical characteristics data, as well as laboratory investigation results, were recorded for the included patients. After acute recovery, patients were followed up for six months and categorized into patients with and without DNS. Out of 174 enrolled patients, 38 (21.8%) developed DNS. The initial Glasgow Coma Scale (GCS), carboxyhemoglobin (COHb) level, CO exposure duration, oxygen saturation, PaCO2, and pulse rate were significantly associated with DNS development by univariate analysis. However, the constructed nomogram based on the multivariable regression analysis included three parameters: duration of CO exposure, COHb level, and GCS with adjusted odd ratios of 1.453 (95% CI: 1.116–1.892), 1.262 (95% CI: 1.126–1.415), and 0.619 (95% CI: 0.486–0.787), respectively. The internal validation of the nomogram exhibited excellent discrimination (area under the curve [AUC] = 0.962), good calibration, and satisfactory decision curve analysis for predicting the DNS probability. The proposed nomogram could be considered a simple, precise, and applicable tool to predict DNS development in acute CO-poisoned patients. [ABSTRACT FROM AUTHOR]

This article, titled "Carbon Monoxide: An Ancient Silent Enemy," provides a historical and contemporary perspective on the impact of carbon monoxide (CO) on humans. It discusses various incidents throughout history where CO poisoning occurred, including the deaths of crew members on Arctic expeditions and the dangers of coal gas in the 19th century. The article also explores the toxic effects of CO on the body and the symptoms of chronic CO poisoning. It concludes by emphasizing the ongoing threat of CO poisoning and the importance of detection and prevention. [Extracted from the article]

While mounting evidence suggests that wildland fire smoke (WFS) inhalation may increase the burden of cardiopulmonary disease, the occupational risk of repeated exposure during wildland firefighting remains unknown. To address this concern, we evaluated the cardiopulmonary function in mice following a cumulative exposure to lab-scale WFS equivalent to a mid-length wildland firefighter (WLFF) career. Dosimetry analysis indicated that 80 exposure hours at a particulate concentration of 22 mg/m3 yield in mice the same cumulative deposited mass per unit of lung surface area as 3600 h of wildland firefighting. To satisfy this condition, male Apoe-/- mice were whole-body exposed to either air or smoldering Douglas fir smoke (DFS) for 2 h/day, 5 days/week, over 8 consecutive weeks. Particulate size in DFS fell within the respirable range for both mice and humans, with a count median diameter of 110 ± 20 nm. Expiratory breath hold in mice exposed to DFS significantly reduced their minute volume (DFS: 27 ± 4; Air: 122 ± 8 mL/min). By the end of the exposure time frame, mice in the DFS group exhibited a thicker (DFS: 109 ± 3; Air: 98 ± 3 μm) and less distensible (DFS: 23 ± 1; Air: 28 ± 1 MPa-1) aorta with reduced diastolic blood augmentation capacity (DFS: 53 ± 2; Air: 63 ± 2 kPa). Cardiac magnetic resonance imaging further revealed larger end-systolic volume (DFS: 14.6 ± 1.1; Air: 9.9 ± 0.9 μL) and reduced ejection-fraction (DFS: 64.7 ± 1.0; Air: 75.3 ± 0.9 %) in mice exposed to DFS. Consistent with increased airway epithelium thickness (DFS: 10.4 ± 0.8; Air: 7.6 ± 0.3 μm), airway Newtonian resistance was larger following DFS exposure (DFS: 0.23 ± 0.03; Air: 0.20 ± 0.03 cmH2O-s/mL). Furthermore, parenchyma mean linear intercept (DFS: 36.3 ± 0.8; Air: 33.3 ± 0.8 μm) and tissue thickness (DFS: 10.1 ± 0.5; Air: 7.4 ± 0.7 μm) were larger in DFS mice. Collectively, mice exposed to DFS manifested early signs of cardiopulmonary dysfunction aligned with self-reported events in mid-career WLFFs.

The present work aims to investigate the cumulative effect of hydrogen enrichment with the fuels of diesel, Neat chlorella vulgaris oil (NCVO), and Chlorella vulgaris methyl ester (CVME) in a mono-cylinder CI engine. The performance, combustion, and emission parameters of diesel, NCVO, and CVME are analyzed and compared to the findings obtained with hydrogen induction in the intake manifold under dual fuel configuration. With the effect of hydrogen infusion, the metrics of performance, combustion and emission parameters are improved. Under maximum load condition, the induction of hydrogen escalates the BTE from 32.74%, 28.01%, and 23.02%–35.39%, 31.40%, and 28.12% with diesel, CVME, and NCVO at maximal hydrogen share energy of 14.38%, 11.50% and 9.61% respectively. Alongside, the enrichment of hydrogen declines the carbon monoxide (CO) from 4.13, 10.38, and 19.24 g/kWh to 3.16, 8.02, and 15.26 g/kWh, unburned hydrocarbons (UHC) from 0.51, 0.71, and 2.02 g/kWh to 0.36, 0.50, and 1.64 g/kWh, smoke opacity from 55%, 75%, and 85%–43%, 67%, and 71% with diesel, CVME, and NCVO respectively. However, the hydrogen's significant flame velocity and immense calorific value confect to an elevated combustion temperature and subsequent rise in heat release rate (HRR) to, cylinder pressure, and emission of nitrogen oxide (NO). Among the tested fuels, diesel posses maximum HRR and cylinder pressure of 80.46 J/0CA and 88.67 bar respectively. Maximum specific NO emission was observed with CVME having 10.80 g/kWh, whereas diesel and NCVO has 9.49 g/kWh and 4.93 g/kWh respectively. • Explored fuel characterization studies of chlorella vulgaris methyl ester. • Poorer combustion and performance with neat chlorella vulgaris oil. • Using chlorella vulgaris methyl ester in compression ignition engine. • Hydrogen induction improves performance and reduces emissions with all tested fuels. [ABSTRACT FROM AUTHOR]

We use air pollution exposure measurements and household survey data from four studies conducted across three countries in sub‐Saharan Africa (SSA) to analyze the association between carbon monoxide (CO) exposure from cooking with biomass and indicators of cognitive impairment. While there is strong evidence on the relationship between ambient air pollution exposure and cognitive impairment from studies in high‐income countries, relatively little research has focused on household air pollution (HAP) in low‐income country settings where risks of HAP exposure are high. This study is the first to our knowledge to focus on the association between HAP exposure (specifically CO exposure) and cognitive impairment across diverse settings in SSA. We use 24‐hour measurements of primary cooks' exposure to CO across four study sites: urban Zambia (n = 493); urban Malawi (n = 130); rural Malawi (n = 102); and urban Rwanda (n = 2,576). We model the estimated percent carboxyhemoglobin (%COHb) of cooks and map values to a toxicological profile for risk of cognitive impairment. We find that across all study settings, cooks' average %COHb levels are below levels of daily concern, but that cooks who use charcoal for preparing greater than 40% of meals are more likely to spend additional time at higher levels of risk. For the urban Zambia sample, we compare %COHb and frequency of charcoal use to a series of cognitive test scores and find no consistent relationships between %COHb and cognitive test scores. High levels of daily CO exposure from cooks across SSA highlight the potential for longer‐term negative cognitive (and other) health outcomes motivating additional research and efforts to characterize and mitigate risk. [ABSTRACT FROM AUTHOR]

INTRODUCTION In this study, we investigate the effects of smoking on pain scores, vital signs, and analgesic consumption in the intraoperative and postoperative period in patients undergoing tympanomastoidectomy surgery. METHODS A total of 100 patients with American Society of Anesthesiologists I-II status, aged 18-55 years, and who were planned to undergo tympanomastoidectomy surgery were divided into two groups: smokers (Group 1) and non-smokers (Group 2). The patients were compared for preoperative, intraoperative, and 24-hour postoperative carboxyhemoglobin, blood pressure, oxygen saturation, respiratory rate, heart rate, pain intensity and verbal numerical rating scales, the extent of patient-controlled tramadol dose, nausea, and vomiting. RESULTS There were 50 individuals in each group. Postoperative analgesic consumption and pain scores were higher in Group 1, and the first postoperative pain was felt earlier. Furthermore, in Group 1, preoperative carboxyhemoglobin levels and postoperative nausea were statistically higher before, after, and at the tenth minute after induction, whereas oxygen saturation was lower. The two groups had no statistical difference regarding intraoperative and postoperative vital signs. Postoperative analgesic consumption was not affected by age or gender. CONCLUSIONS Smoking changes postoperative pain management, especially for this kind of operation, and these patients feel more pain and need more postoperative analgesic doses. Therefore, effective postoperative pain control should take account of smoking behavior, and analgesic doses may need to be adjusted for patients who smoke. [ABSTRACT FROM AUTHOR]

Introduction The prevalence of waterpipe tobacco smoking is increasing globally. Biomarkers of waterpipe tobacco smoke (WTS) exposure are less studied. Aims and Methods To identify the types of biomarkers of WTS exposure and estimate changes in biomarker concentrations pre- to post-WTS exposure. PubMed, Embase, Web of Science, CINAHL Plus, PsycINFO, and Cochrane Library were searched for studies up to April 24, 2023. The types of biomarkers were identified. Random-effects models were used to estimate changes in biomarker concentrations pre- to post-WTS exposure. Results Seventy-three studies involving 3755 participants exposed to WTS (49% male, mean age: 24.8 years) and 11 types of biomarkers of WTS exposure were identified. The biomarkers included tobacco alkaloids, expired carbon monoxide (eCO), carboxyhemoglobin (COHb), tobacco-specific nitrosamines, volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), heavy metals, unmetabolized VOCs, unmetabolized PAHs, furan metabolites, and heterocyclic aromatic amines. Compared with pre-WTS exposure, eCO (breath; mean difference [MD] 27.00 ppm; 95% confidence interval [CI]: 20.91 to 33.08), COHb (blood; MD 4.30%; 95%CI: 2.57 to 6.03), COHb (breath; MD 7.14%; 95%CI: 4.96 to 9.31), nicotine (blood; MD 8.23 ng/mL; 95%CI: 6.27 to 10.19), and cotinine (urine; MD 110.40 ng/mL; 95%CI: 46.26 to 174.54) significantly increased post-WTS exposure. Conclusions Biomarkers of WTS exposure were systematically identified. The similarity between the biomarkers of WTS exposure and those of cigarette smoke and higher concentrations of some biomarkers post-WTS exposure underscore the need for further research on applying biomarkers in surveillance, interventions, and regulations to mitigate the harms of waterpipe tobacco smoking. Implications This study provides the first comprehensive overview of biomarkers investigated and available for assessing WTS exposure and their concentration changes in the human body. Researchers can use biomarkers such as eCO, COHb, nicotine, and cotinine to measure the health risks associated with WTS exposure and objectively evaluate the effectiveness of public health interventions aimed at reducing waterpipe tobacco smoking. Public health policymaking can also be informed through increased biomarker concentrations following WTS exposure, to implement regulations and public health education campaigns on limiting or preventing waterpipe tobacco smoking. [ABSTRACT FROM AUTHOR]

Carbon monoxide poisoning is one of the leading causes of mortality and morbidity by poisoning in the world. Signs and symptoms are nonspecific and related to impaired oxygen delivery to tissues, with the brain being the most affected organ due to its high oxygen demand. CO-Hb is a poor indicator of severity and long-term outcome, with clinicians relying more on clinical features such as level of consciousness and need for intubation, organ dysfunction and shock and also pH level. A 45-year-old female was found unconscious in her home with the fireplace lit and smoke all over the house. She was last seen well 18 hours before. She was brought to the emergency department and was admitted to the ICU in coma and cardiogenic shock, with a metabolic acidosis with hyperlactacidemia and a CO-Hb level of 15.5%. Laboratorial investigation revealed hepatic cytolysis, acute renal failure, rhabdomyolysis and a troponin I level of 338 ng/L. ECG showed no acute myocardial ischemia. Echocardiogram revealed diffuse hypokinesia with an ejection fraction of 25%. Head CT scan showed bilateral and symmetrical hypodensities of the globus pallidus. The patient underwent hyperbaric oxygen treatment with full neurological and cardiac recovery, allowing extubation 48 hours after admission. This rare severe case of coma due to carbon monoxide intoxication with globus pallidus injury and cardiogenic shock was successfully treated with hyperbaric oxygen, showing that it can be the right treatment choice in these cases, with an excellent impact on neurological and cardiac outcome. [ABSTRACT FROM AUTHOR]

Fire-related deaths are usually a consequence of carbon monoxide (CO) poisoning or shock from thermal injuries. In humans, high levels of carboxyhemoglobin (COHb) concentrations in the blood can support a diagnosis of CO poisoning. In veterinary medicine, few studies investigated the pathological changes and blood COHb% in fire victims, and no data are available on post-mortem changes in blood gas composition due to fire. This study aims to investigate the pathological changes and COHb levels in both animal victims of fire and cadavers experimentally exposed to fire. For this purpose, dogs were selected and subdivided into three groups. Group A comprised 9 adult dogs, and Group B comprised 7 puppies that died under fire-related conditions. Group C was represented by 4 dog cadavers experimentally exposed to heat and smoke. A complete macroscopic, histological, and COHb evaluation were performed on each animal. Animals in Groups A and B showed cherry-red discoloration, thermal-injuries and soot deposits along the respiratory tract. Animals in Group C showed thermal injuries and soot deposits limited to the upper respiratory tract. The mean COHb% values in cadavers in Group C were lower than those observed in the other groups but higher compared to the values detected before the heat and smoke treatment. These findings suggest that both pathological changes and COHb analysis are valid tools for investigating fire-related deaths in dogs. However, the increase of COHb levels in cadavers exposed postmortem to heat and smoke highlights how the COHb analysis should always be evaluated together with macroscopical and microscopical findings to avoid significant misjudgments in investigating fire-related fatalities in veterinary forensic practice. [ABSTRACT FROM AUTHOR]

Carbon monoxide (CO) poisoning is a leading cause of poison-related morbidity and mortality worldwide. By binding to hemoglobin and other heme-containing proteins, CO reduces oxygen delivery and produces tissue damage. Prompt treatment of CO-poisoned patients is necessary to prevent acute and long-term complications. Oxygen therapy is the only available treatment. Visible light has been shown to selectively dissociate CO from hemoglobin with high efficiency without affecting oxygen affinity. Pulmonary phototherapy has been shown to accelerate the rate of CO elimination in CO poisoned mice and rats when applied directly to the lungs or via intra-esophageal or intra-pleural optical fibers. The extracorporeal removal of CO using a membrane oxygenator with optimal characteristic for blood exposure to light has been shown to accelerate the rate of CO illumination in rats with or without lung injury and in pigs. The development of non-invasive techniques to apply pulmonary phototherapy and the development of a compact, highly efficient membrane oxygenator for the extracorporeal removal of CO in humans may provide a significant advance in the treatment of CO poisoning. • Visible light selectively dissociates CO from hemoglobin without affecting oxygen binding. • Pulmonary phototherapy has been shown to accelerate the rate of CO elimination in mice and rats. • The extracorporeal removal of CO using phototherapy (ECCOR-P) accelerates CO elimination in small and large animals. • Pulmonary phototherapy and ECCOR-P development may provide a significant advance for treating CO poisoning. [ABSTRACT FROM AUTHOR]

Background: The continuous exposure of blood to a non-biological surface during extracorporeal membrane oxygenation (ECMO) may lead to progressive thrombus formation in the oxygenator, hemolysis and consequently impaired gas exchange. In most centers oxygenator performance is monitored only on a once daily basis. Carboxyhemoglobin (COHb) is generated upon red cell lysis and is routinely measured with any co-oximetry performed to surveille gas exchange and acid–base homeostasis every couple of hours. This retrospective cohort study aims to evaluate COHb in the arterial blood gas as a novel marker of oxygenator dysfunction and its predictive value for imminent oxygenator change. Results: Out of the 484 screened patients on ECMO 89, cumulatively requiring 116 oxygenator changes within 1833 patient days, including 19,692 arterial COHb measurements were analyzed. Higher COHb levels were associated with lower post-oxygenator pO2 (estimate for log(COHb): − 2.176 [95% CI − 2.927, − 1.427], p < 0.0001) and with a shorter time to oxygenator change (estimate for log(COHb): − 67.895 [95% CI − 74.209, − 61.542] hours, p < 0.0001). COHb was predictive of oxygenator change within 6 h (estimate for log(COHb): 5.027 [95% CI 1.670, 15.126], p = 0.004). Conclusion: COHb correlates with oxygenator performance and can be predictive of imminent oxygenator change. Therefore, longitudinal measurements of COHb in clinical routine might be a cheap and more granular candidate for ECMO surveillance that should be further analyzed in a controlled prospective trial design. [ABSTRACT FROM AUTHOR]

CO2 anesthesia is the most common method for immobilizing Drosophila for research purposes. But CO2 exposure has consequences—it can impact fertility, behavior, morphogenesis, and cytoskeletal dynamics. In this respect, Drosophila is an outstanding model for studying the impact of CO2 exposure on tissues. In this study we explored the response of intracellular pH (pHi) to a one-minute CO2 pulse using a genetically encoded, ubiquitously expressed pH sensor, tpHusion, to monitor pHi within a live, intact, whole fly. We compared wild-type flies to flies lacking Imaginal disc growth factors (Idgfs), which are chitinase-like proteins that facilitate developmental processes and the innate immune response. Morphogenetic and cytoskeletal defects in Idgf-null flies are enhanced after CO2 exposure. We found that pHi drops sharply within seconds of the beginning of a CO2 pulse and recovers over several minutes. The initial profile was nearly identical in control and Idgf-null flies but diverged as the pHi returned to normal. This study demonstrates the feasibility of monitoring pH in live adult Drosophila. Studies exploring pH homeostasis are important for understanding human pathologies associated with pH dysregulation. [ABSTRACT FROM AUTHOR]

L'intoxication au monoxyde de carbone (CO) est une pathologie fréquente et responsable d'une morbi-mortalité élevée dans le monde. Peu d'études en Tunisie se sont intéressées à la population pédiatrique touchée par ce problème de la santé publique. Le but de cette étude était de déterminer le profil épidémiologique de l'intoxication au CO ainsi que ses aspects cliniques, paracliniques, thérapeutiques et évolutifs. Notre étude a inclus les observations d'intoxications au CO chez les enfants hospitalisés au service de pédiatrie C de l'hôpital d'enfants de Tunis, sur une période de trois ans. Nous avons colligé 199 cas d'intoxication au CO chez les enfants. L'âge moyen était de 5,43 ans avec un sex-ratio de 0,98. La localisation de la source de CO était à l'intérieur du domicile dans 73,2 % des cas et il s'agissait du chauffe-bain à gaz dans 68,8 % des cas. L'intoxication était collective dans 94,9 % des cas et elle survenait durant le mois de janvier dans 35,8 % des cas. Les manifestations cliniques étaient des céphalées dans 69 % des cas. Le taux de la carboxyhémoglobine était pathologique dans 73,9 % des cas. Tous les patients ont reçu une oxygénothérapie normobare et seulement 3,6 % des patients ont eu une séance d'oxygénothérapie hyperbare. Nous n'avons déploré aucun cas de décès dans notre série. L'intoxication au CO reste un problème de santé publique en Tunisie. Le risque de complications, notamment neuropsychiatriques, impose un suivi clinique et éventuellement neuroradiologique de ces victimes. Carbon monoxide (CO) poisoning is a common pathology responsible for high morbidity and mortality worldwide. Few studies in Tunisia have focused on the pediatric population. The purpose of this study was to determine the epidemiological profile of CO poisoning as well as its clinical, paraclinical, therapeutic and evolutionary aspects. Our study included observations of CO poisoning in children hospitalized in the pediatric department C of the children's hospital in Tunis, over a period of 3 years. We have collected 199 cases of CO poisoning in children. The average age was 5.43 years with a sex ratio of 0.98. The source of CO was inside the home in 73.2% of cases and it was the gas bath heater in 68.8% of cases. The intoxication was collective in 94.9% of the cases and it occurred during the month of January in 35.8% of the cases. The clinical manifestations were headaches in 69% of cases. The rate of carboxyhemoglobin was pathological in 73.9% of cases. All patients received normobaric oxygen therapy and only 3.6% of patients had a hyperbaric oxygen therapy session. We did not deplore any case of death in our study. CO poisoning remains a public health problem in our country with high morbidity. The risk of secondary complications, particularly neuropsychiatric, requires clinical and possibly neuroradiological monitoring of these victims. [ABSTRACT FROM AUTHOR]

Oxidative stress represents a hallmark for many degenerative pathologies of the Central Nervous System. Throughout life, the constant pressure of noxious stimuli and/or episodes of traumatic events may expose the brain to a microenvironment where the non-balanced reactive oxygen species inevitably lead to neuronal loss and cognitive decline. HO-1, a 32 kDa heat-shock protein catalyzing the degradation of heme into carbon monoxide (CO), iron and biliverdin/bilirubin is considered one of the main antioxidant defense mechanisms playing pivotal roles in neuroprotection. Restoring the redox homeostasis is the goal of many natural or synthetic antioxidant molecules pursuing beneficial effects on brain functions. Here, we investigated the antioxidant capacity of four selected benzofuran-2-one derivatives in a cellular model of neurodegeneration represented by differentiated SH-SY5Y cells exposed to catechol-induced oxidative stress. Our main results highlight how all the molecules have antioxidant properties, especially compound 9, showing great abilities in reducing intracellular ROS levels and protecting differentiated SH-SY5Y cells from catechol-induced death. This compound above all seems to boost HO-1 mRNA and perinuclear HO-1 protein isoform expression when cells are exposed to the oxidative insult. Our findings open the way to consider benzofuran-2-ones as a novel and promising adjuvant antioxidant strategy for many neurodegenerative disorders. [ABSTRACT FROM AUTHOR]

Background/Objective : Hydroxocobalamin is indicated for cyanide poisoning and its package insert states it should be given "without delay". We sought to evaluate time to administration and clinical characteristics when hydroxocobalamin was administered in a quaternary care academic medical center. Methods : All hydroxocobalamin administrations from January 1, 2007 to December 31, 2018 were analyzed. Data points recorded were: carboxyhemoglobin, cyanide and methemoglobin levels, hospital time and course, time and dose of hydroxocobalamin administration, lactate and bicarbonate levels, initial and nadir pH, initial heart rate, and initial and lowest systolic blood pressure. Results : Fifty-six cases were identified. One case was excluded as hydroxocobalamin was administered for nitroprusside toxicity. Among 55 cases analyzed, 93% (n = 51) were adults. Median hospital length of stay was 4.3 days (IQR 2.5 to 12). Burn, inhalation injury, and smoke inhalation were 80% of admitting diagnoses. Median time to hydroxocobalamin administration was 208 minutes (IQR 62.5 to 330). Eleven of 55 cases died. Hydroxocobalamin was given within 60 minutes of arrival in 12 cases, of which 3 died. All adults received 5 g of hydroxocobalamin. Time to hydroxocobalamin administration was longer in death cases [median: 221 minutes (IQR 119 to 594)] vs survivors [median: 184.5 minutes (IQR 62.8 to 315)]. Seventeen cases had cyanide levels drawn, with 9 being measurable, but none were toxic. Conclusions : Significant delay in hydroxocobalamin administration was seen in this study. Cases that resulted in death had significantly longer times to hydroxocobalamin administration. Further studies are warranted to identify reasons for delays in hydroxocobalamin administration. [ABSTRACT FROM AUTHOR]

No definitive prognostic biomarkers for carbon monoxide (CO) poisoning have been proposed. The aim of this study is to investigate, through a systematic literature review and pooled analysis, whether red blood cell distribution width (RDW) can predict disease severity in CO-poisoned patients. We performed an electronic search in Scopus and PubMed using the keywords: 'red blood cell distribution width' OR 'RDW' AND 'carbon monoxide' AND 'poisoning,' with no time or language restrictions (i.e. through August 2023) to find clinical studies that examined the value of RDW in patients with varying severity of CO poisoning. The analysis was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) 2020 reporting checklist. We identified 29 articles, seven of which were included in our analysis, with a total of 1979 CO-poisoned patients, 25.9% of whom were severely ill. In all but one of the studies, the RWD mean or median value was higher in CO-poisoned patients with severe disease. The weighted mean difference (WMD) of RDW was 0.36 (95% confidence interval (CI), 0.26–0.47)%. In the three articles in which the severity of illness in CO-poisoned patients was defined as cardiac injury, the WMD of the RDW was 1.26 (95%CI, 1.02–1.50)%. These results suggest that monitoring RDW in CO-poisoned patients may help to determine the severity of disease, particularly cardiac injury. [ABSTRACT FROM AUTHOR]

Carbon monoxide can cause severe harm to humans even at low concentrations. Metal Oxide Semiconductor (MOS) carbon monoxide gas sensors have excellent sensing performance regarding sensitivity, selectivity, response speed, and stability, making them very desirable candidates for carbon monoxide monitoring. However, MOS gas sensors generally work at temperatures higher than room temperature, and need a heating source that causes high power consumption. High power consumption is a great problem for long-term portable monitoring devices for point-of-care or wireless sensor nodes for IoT application. Room-temperature MOS carbon monoxide gas sensors can function well without a heater, making them rather suitable for IoT or portable applications. This review first introduces the primary working mechanism of MOS carbon monoxide sensors and then gives a detailed introduction to and analysis of room-temperature MOS carbon monoxide sensing materials, such as ZnO, SnO2, and TiO2. Lastly, several mechanisms for room-temperature carbon monoxide sensors based on MOSs are discussed. The review will be interesting to engineers and researchers working on MOS gas sensors. [ABSTRACT FROM AUTHOR]

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ABSTRACT Objective: To identify and characterize the population of Pediatric patients referred to our hyperbaric oxygen therapy center. Methods: Retrospective and observational study, including pediatric patients treated with hyperbaric oxygen therapy, from 2006 to 2021, at the hyperbaric medicine reference center in the north of Portugal. Variables of interest were extracted from electronic medical records. Results: Our study included 134 patients. The most frequent reasons for referral were carbon monoxide poisoning (n=59) and sudden sensorineural hearing loss (n=41). In 75 cases (56%), treatment was initiated in an urgent context. Symptom presentation at Emergency Department varied among patients, the most frequent being headache and nausea/vomiting. Concerning carbon monoxide poisoning, the most common sources were water heater, fireplace/brazier, and boiler. Regarding adverse effects, it was identified one case of intoxication by oxygen and four cases of middle ear barotrauma. Conclusions: The most frequent cause for referral was carbon monoxide poisoning. All patients evolved favorably, with few side effects being reported, emphasizing the safety of this therapy. While most pediatricians may not be aware of the potential benefits arising with hyperbaric oxygen therapy, it is of upmost importance to promote them, so that this technique is increasingly implemented.

In today’s world, where stress and busyness are an integral part of everyday life, energy drinks have become not only a means of satisfying the need for energy and maintenance of vitality, but also a symbol of lifestyle, an important element of the modern culture of consumption. The speed and efficiency they promise attract the attention of consumers, especially those who are constantly on the move. Such drinks have become popular not only among young people, but also among everyone who seek to maintain their activity and efficiency during the day. The purpose of the work was to investigate the dynamics of changes in the level of total hemoglobin and its forms, in particular oxy-, carboxy-, sulf-, met-, and dyshemoglobin under the conditions of energy drink consumption. The study was conducted using male Wistar rats weighing 150–220 g kept in the vivarium under appropriate lighting conditions, temperature, humidity and standard diet. All the animals had free access to feed (based on daily requirements) and water (based on 20 ml of water per rat per day). The experiment was carried out in compliance with the requirements of the European Convention for the Protection of Vertebrate Animals used for Experimental and Scientific Purposes (Strasbourg, 1986). The animals were divided into five groups: the 1st group received drinking water (intact control); the 2nd–5th groups received daily the non-alcoholic energy drink “Burn” per os for a month. The calculation of the required amount of drink for administration per one rat was based per 1 kg of body weight. To monitor the growth and development, we weighted the rats at the beginning and at each stage of the experiment. The material (blood) was taken on the 1st (2nd group), 10th (3rd group), 20th (4th group) and 30th day (5th group) after the completion of the experiment under anesthesia (intramuscularly sodium thiopental, 60 mg/kg). The total hemoglobin level was determined with the Mythic 18 hematological analyzer. Determination of the content of oxyhemoglobin, methemoglobin, sulfhemoglobin and carboxyhemoglobin was performed spectrophotometrically. The obtained data indicate significant changes in both the total level of hemoglobin and its ligand forms, in particular, a decrease in the level of oxyhemoglobin and the accumulation of dyshemoglobins, such as methemoglobin, sulfhemoglobin, and carboxyhemoglobin. As evidenced by the obtained results, the consumption of energy drinks leads to the oxygen homeostasis violation, the development of tissue hypoxia and can cause structural and functional disorders in the body under such conditions.

The main method for estimating the level of arterial blood oxygenation is pulse oximetry, which has the advantages of being fast, simple, reliable, and non-invasive. However, in well-known pulse oximeters, oxygen saturation is determined only by hemoglobin functional fractions, which reduces the device accuracy and is unacceptable in certain clinical cases. The known pulse oximeter improvement that considers the dysfunctional fraction concentration, especially carboxyhemoglobin, when measuring the level of blood oxygenation is an actual scientific and technical task. The research subjects. Mathematical, algorithmic, and technical support of a pulse oximeter that measures blood oxygenation levels considering the carboxyhemoglobin concentration. Objective. To expand the pulse oximeter functionality to consider the concentration of carboxyhemoglobin in arterial blood. Methods. Methods of computer simulation for developing a model and estimating the pulse oximeter accuracy that measures the blood oxygenation level considering the carboxyhemoglobin concentration. Results. The theoretical statements of measuring the level of blood oxygenation considering the carboxyhemoglobin concentration and the simplest pulse oximeter structural diagram for measuring are developed. An additional LED used in the pulse oximeter is proposed, and the wavelength choice is justified on the condition of maximizing the carboxyhemoglobin contribution to the optical density of the biological object. Computer models of a traditional pulse oximeter and a pulse oximeter with an additional LED were developed, simulation research was conducted using the developed models, and the device accuracy for measuring the level of blood oxygenation was estimated considering the carboxyhemoglobin concentration. Conclusions. Simulation studies based on the developed models show that the proposed pulse oximeter, compared with the known one, allows determining and estimating a decrease in blood oxygenation caused by the carboxyhemoglobin concentration increasing in the patient’s blood. Considering that light is also absorbed by the third derivative of hemoglobin, carboxyhemoglobin, increases the accuracy of the proposed pulse oximeter in measuring functional saturation.

Objective: The effect marker club cell protein (CC16) is secreted by the epithelium of the small respiratory tract into its lumen and passes into the blood. Increased amounts of CC16 in serum are observed during acute epithelial lung injury due to air pollutants. CC16 in serum was determined as part of this cross-sectional study in underground potash miners on acute and chronic health effects from exposures to diesel exhaust and blasting fumes. Methods: Nitrogen oxides, carbon monoxide, and diesel particulate matter were measured in 672 workers at a German potash mining site on a person-by-person basis over an early shift or midday shift, together with CC16 serum concentrations before and after the respective shift. CC16 concentrations and CC16 shift-differences were evaluated with respect to personal exposure measurements and other quantitative variables by Spearman rank correlation coefficients. CC16 shift-differences were modeled using multiple linear regression. Above-ground workers as reference group were compared to the exposed underground workers. Results: Serum concentrations of CC16 were influenced by personal characteristics such as age, smoking status, and renal function. Moreover, they showed a circadian rhythm. While no statistically significant effects of work-related exposure on CC16 concentrations were seen in never smokers, such effects were evident in current smokers. Conclusion: The small airways of current smokers appeared to be vulnerable to the combination of measured work-related exposures and individual exposure to smoking. Therefore, as health protection of smokers exposed to diesel exhaust and blasting fumes, smoking cessation is strongly recommended. [ABSTRACT FROM AUTHOR]

Aim: The study aimed to investigate whether there are differences in carboxyhemoglobin, bilirubin and hemoglobin values of neonates born by normal spontaneous vaginal birth (NSVD) (without anesthesia) and elective spinal cesarean section (CS) and its effect on neonatal jaundice. Materials and Methods: A total of 110 healthy neonates without any risk factors for neonatal hyperbilirubinemia were included in the study. There were fifty-five neonates in both NVSD and spinal CS groups. COHb, bilirubin and Hb values which were measured from umbilical cord blood (as cord) and capillary blood taken from the heel 4-6 hours after birth (as post cord) were recorded. Results: No statistically significant difference was found between the groups in terms of birthweight, maternal age, APGAR scores, and gender (p>0.05). There was a statistical difference between the groups according to the mean of gestational age, and it was observed that the mean of gestational age in spinal CS group was lower than in NSVD group (38.30±1.2 and 39.16±1.39 respectively) (p=0.001). Umbilical cord COHb levels in spinal CS group were higher than in NSVD group, but there was no statistically significant difference between groups (1.01±0.15 and 0.99±0.20 respectively, p=0.22). Furthermore, the differences between groups in term of mean of bilirubin and Hb levels in cord and post cord were not statistically significant (>0.05). But, it was determined that post cord COHb levels were higher than in NVSD group, and this difference was statistically significant (p=0.028). Additionally, it was found that the mean rank of COHb, bilirubin, and Hb in cord and post cord values were statistically significantly different between the groups (p < 0.05). Conclusion: It should be kept in mind of that the anesthetic agent may also be a factor in bilirubin increases that occurs in neonatal hyperbilirubinemia without an underlying risk factor. [ABSTRACT FROM AUTHOR]

The enzyme heme oxygenase-1 (HO-1) is pivotal in reproductive processes, particularly in placental and vascular development. This study investigated the role of HO-1 and its byproduct, carbon monoxide (CO), in trophoblastic spheroid implantation. In order to deepen our understanding of the role of HO-1 during implantation, we conducted in vivo experiments on virgin and pregnant mice, aiming to unravel the cellular and molecular mechanisms. Using siRNA, HO-1 was knocked down in JEG-3 and BeWo cells and trophoblastic spheroids were generated with or without CO treatment. Adhesion assays were performed after transferring the spheroids to RL-95 endometrial epithelial cell layers. Additionally, angiogenesis, stress, and toxicity RT2-Profiler™ PCR SuperArray and PCR analyses were performed in uterine murine samples. HO-1 knockdown by siRNA impeded implantation in the 3D culture model, but this effect could be reversed by CO. Uteruses from virgin Hmox1−/− females exhibited altered expression of angiogenesis and stress markers. Furthermore, there was a distinct expression pattern of cytokines and chemokines in uteruses from gestation day 14 in Hmox1−/− females compared to Hmox1+/+ females. This study strongly supports the essential role of HO-1 during implantation. Moreover, CO appears to have the potential to compensate for the lack of HO-1 during the spheroid attachment process. The absence of HO-1 results in dysregulation of angiogenesis and stress-related genes in the uterus, possibly contributing to implantation failure. [ABSTRACT FROM AUTHOR]

Some studies have shown the effect of air pollution on migraine. However, it needs to be confirmed in larger-scale studies, as scientific evidence is scarce regarding the association between air pollution and migraine. Therefore, this systematic review aims to determine whether there are associations between outdoor air pollution and migraine. A literature search was performed in Scopus, Medline (via PubMed), EMBASE, and Web of Science. A manual search for resources and related references was also conducted to complete the search. All observational studies investigating the association between ambient air pollution and migraine, with inclusion criteria, were entered into the review. Fourteen out of 1417 identified articles met the inclusion criteria and entered the study. Among the gaseous air pollutants, there was a correlation between exposure to nitrogen dioxide (NO2) (78.3% of detrimental relationships) and carbon monoxide (CO) (68.0% of detrimental relationships) and migraine, but no apparent correlation has been found for sulfur dioxide (SO2) (21.2% of detrimental relationships) and ozone (O3) (55.2% of detrimental relationships). In the case of particulate air pollutants, particulate matter with a diameter of 10 μm or less (PM10) (76.0% of detrimental relationships) and particulate matter with a diameter of 2.5 μm or less (PM2.5) (61.3% of detrimental relationships) had relationships with migraine. In conclusion, exposure to NO2, CO, PM10, and PM2.5 is associated with migraine headaches, while no conclusive evidence was found to confirm the correlation between O3 and SO2 with migraine. Further studies with precise methodology are recommended in different cities around the world for all pollutants with an emphasis on O3 and SO2. [ABSTRACT FROM AUTHOR]

We conducted ab initio valence bond (VB) calculations employing the valence bond self-consistent field (VBSCF) and breathing orbital valence bond (BOVB) methods to investigate the nature of the coordination bonding between ferrous heme and carbon monoxide (CO) within cytochrome P450. These calculations revealed the significant influence exerted by both proximal and equatorial ligands on the π-backdonation effect from the heme to the CO. Moreover, our VB calculations unveiled a phenomenon of synergistic charge transfer (sCT). In the case of ferrous heme–CO bonding, the significant stabilization in this sCT arises from cooperative resonance between the VB structures associated with σ donation and π backdonation. Unlike many other ligands, CO possesses the unique ability to establish two mutually perpendicular π-backdonation orbital interaction pairs, leading to an intensified stabilization attributed to σ–π resonance. Furthermore, while of a smaller energy magnitude, sCT due to one π–π pair is also present, contributing to the differential stabilization of ferrous heme–CO bonding. [ABSTRACT FROM AUTHOR]

Carbon monoxide (CO) poisoning is difficult to diagnose owing to its nonspecific symptoms. Multiwave pulse oximetry can be used to quickly screen patients for CO poisoning. However, few studies have analyzed patients with CO poisoning who presented to the emergency department (ED). The primary aim of our study was to determine the correlation between COHb levels measured in blood gas analysis and COHb levels measured in multiwave pulse oximetry. Secondary aims were the sensitivity and specificity of the COHb level cutoff value using multiwave pulse oximetry to predict a 25% COHb level in blood gas analysis. This single-center retrospective observational study included patients with CO poisoning who visited the ED of a university-affiliated hospital in Seoul, Korea between July 2021 and June 2023. COHb poisoning was determined using blood gas analysis and multiwave pulse oximetry. The correlation of COHb levels between the two tests was evaluated using correlation analysis. The area under the receiver operating characteristic curve (AUC) of multiwave pulse oximetry was calculated to predict COHb levels from the blood gas analysis. The optimal cutoff values, sensitivity, and specificity of COHb were determined. A total of 224 patients who had COHb levels measured using both multiwave pulse oximetry and blood gas analysis were included in the analysis. In the correlation analysis, COHb showed a high positive correlation with COHb measured using blood gas analysis (Spearman correlation coefficient = 0.86, p < 0.001). The AUC of COHb measured by multiwave pulse oximetry to predict 25% of the COHb level (which can be an indication of hyperbaric oxygen treatment) measured by blood gas analysis was 0.916. When the COHb levels measured with multiwave pulse oximetry were 20% the sensitivity was 81% and the specificity was 83%, and when the COHb levels were 25% the sensitivity was 50% and the specificity was 95%. The COHb value measured using multiwave pulse oximetry blood gas analysis showed a high correlation. However, additional research using large-scale studies is required for validation. [ABSTRACT FROM AUTHOR]

Recently, myriad studies have defined the versatile abilities of gasotransmitters and their synthesizing enzymes to play a "Maestro" role in orchestrating several oncological and non-oncological circuits and, thus, nominated them as possible therapeutic targets. Although a significant amount of work has been conducted on the role of nitric oxide (NO) and carbon monoxide (CO) and their inter-relationship in the field of oncology, research about hydrogen sulfide (H2S) remains in its infancy. Recently, non-coding RNAs (ncRNAs) have been reported to play a dominating role in the regulation of the endogenous machinery system of H2S in several pathological contexts. A growing list of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) are leading the way as upstream regulators for H2S biosynthesis in different mammalian cells during the development and progression of human diseases; therefore, their targeting can be of great therapeutic benefit. In the current review, the authors shed the light onto the biosynthetic pathways of H2S and their regulation by miRNAs and lncRNAs in various oncological and non-oncological disorders. [ABSTRACT FROM AUTHOR]

Duplicate measure of hemoglobin mass by carbon monoxide (CO)-rebreathing is a logistical challenge as recommendations prompt several hours between measures to minimize CO-accumulation. This study investigated the feasibility and reliability of performing duplicate CO-rebreathing procedures immediately following one another. Additionally, it was evaluated whether the obtained hemoglobin mass from three different CO-rebreathing devices is comparable. Fifty-five healthy participants (22 males, 23 females) performed 222 duplicate CO-rebreathing procedures in total. Additionally, in a randomized cross-over design 10 participants completed three experimental trials, each including three CO-rebreathing procedures, with the first and second separated by 24 h and the second and third separated by 5–10 min. Each trial was separated by >48 h and conducted using either a glass-spirometer, a semi-automated electromechanical device, or a standard three-way plastic valve designed for pulmonary measurements. Hemoglobin mass was 3 ± 22 g lower (p < 0.05) at the second measure when performed immediately after the first with a typical error of 1.1%. Carboxyhemoglobin levels reached 10.9 ± 1.3%. In the randomized trial, hemoglobin mass was similar between the glass-spirometer and three-way valve, but ∼6% (∼50 g) higher for the semi-automated device. Notably, differences in hemoglobin mass were up to ∼13% (∼100 g) when device-specific recommendations for correction of CO loss to myoglobin and exhalation was followed. In conclusion, it is feasible and reliable to perform two immediate CO-rebreathing procedures. Hemoglobin mass is comparable between the glass-spirometer and the three-way plastic valve, but higher for the semi-automated device. The differences are amplified if the device-specific recommendations of CO-loss corrections are followed. [ABSTRACT FROM AUTHOR]

Simple Summary: Brachycephalic dogs are more prone to develop upper airway respiratory complications in the postoperative period. The application of pre- and postoperative continuous positive airway pressure (CPAP) therapy has been suggested in human patients with obstructive sleep apnea to enhance oxygenation, diminish airway swelling, reduce the work of breathing, and promote recovery. Brachycephalic dogs undergoing various surgical procedures were included in this study and assigned to receive either standard oxygen supplementation (NO-CPAP group) or oxygen supplementation combined with CPAP (CPAP group). The CPAP group showed significant improvements in respiratory function compared with the NO-CPAP group (p < 0.001). The incidence of reintubation and helmet intolerance was higher in the NO-CPAP group (18% and 15.6%, respectively) than in the CPAP group (0%). This study highlights the potential benefits of incorporating CPAP, delivered through a pediatric helmet, in the perioperative management of brachycephalic dogs. This study aimed to evaluate the benefits of applying 5 cmH2O of CPAP using a pediatric helmet during the recovery phase from general anesthesia in brachycephalic dogs. Brachycephalic dogs undergoing various surgical procedures were included in this study, and a total of 64 subjects were randomly assigned to receive either standard oxygen supplementation (NO-CPAP group) or oxygen supplementation combined with CPAP (CPAP group). This study evaluated arterial blood pH, blood gas partial pressures of O2 and CO2, arterial blood O2 saturation, and related parameters during recovery. The dogs were monitored, and helmet tolerance was assessed using predefined criteria. Of the initially assessed 69 dogs, 64 were enrolled: 32 in the CPAP group and 32 in the NO-CPAP group. Fifteen dogs in the NO-CPAP group were excluded based on predetermined criteria. The CPAP group showed significant improvements in PaO2, PaO2/FiO2, P(A-a)O2, F-Shunt, and respiratory rate compared with the NO-CPAP group (p < 0.001). The incidence of reintubation and helmet intolerance was higher in the NO-CPAP group (18% and 15.6%, respectively) than in the CPAP group (0%). This study highlights the potential benefits of incorporating CPAP, delivered through a pediatric helmet, in the perioperative management of brachycephalic dogs. [ABSTRACT FROM AUTHOR]

Rationale: Chronic obstructive pulmonary disease (COPD) hospitalizations are a major burden on patients. Diffusing capacity of the lung for carbon monoxide (DLCO) is a potential predictor that has not been studied in large cohorts. Objectives: This study used electronic health record data to evaluate whether clinically obtained DLCO predicts COPD hospitalizations. Methods: We performed time-to-event analyses of individuals with COPD and DLCO measurements from the Johns Hopkins COPD Precision Medicine Center of Excellence. Cox proportional hazard methods were used to model time from DLCO measurement to first COPD hospitalization and composite first hospitalization or death, adjusting for age, sex, race, body mass index, smoking status, forced expiratory volume in 1 second (FEV1), history of prior COPD hospitalization, and comorbidities. To identify the utility of including DLCO in risk models, area under the receiver operating curve (AUC) values were calculated for models with and without DLCO. Results were externally validated in a separate analogous cohort. Results: Of 2,793 participants, 368 (13%) had a COPD hospitalization within 3 years. In adjusted analyses, for every 10% decrease in DLCO% predicted, risk of COPD hospitalization increased by 10% (hazard ratio, 1.1; 95% confidence interval, 1.1--1.2; P,0.001). Similar associations were observed for COPD hospitalizations or death. The model including demographics, comorbidities, FEV1, DLCO, and prior COPD hospitalizations performed well, with an AUC of 0.85 and an AUC of 0.84 in an external validation cohort. Conclusions: Diffusing capacity is a strong predictor of COPD hospitalizations in a clinical cohort of individuals with COPD, independent of airflow obstruction and prior hospitalizations. These findings support incorporation of DLCO in risk assessment of patients with COPD. [ABSTRACT FROM AUTHOR]

A photoacoustic sensor system (PAS) intended for carbon dioxide (CO2) blood gas detection is presented. The development focuses on a photoacoustic (PA) sensor based on the so-called two-chamber principle, i.e., comprising a measuring cell and a detection chamber. The aim is the reliable continuous monitoring of transcutaneous CO2 values, which is very important, for example, in intensive care unit patient monitoring. An infrared light-emitting diode (LED) with an emission peak wavelength at 4.3 µm was used as a light source. A micro-electro-mechanical system (MEMS) microphone and the target gas CO2 are inside a hermetically sealed detection chamber for selective target gas detection. Based on conducted simulations and measurement results in a laboratory setup, a miniaturized PA CO2 sensor with an absorption path length of 2.0 mm and a diameter of 3.0 mm was developed for the investigation of cross-sensitivities, detection limit, and signal stability and was compared to a commercial infrared CO2 sensor with a similar measurement range. The achieved detection limit of the presented PA CO2 sensor during laboratory tests is 1 vol. % CO2. Compared to the commercial sensor, our PA sensor showed less influences of humidity and oxygen on the detected signal and a faster response and recovery time. Finally, the developed sensor system was fixed to the skin of a test person, and an arterialization time of 181 min could be determined. [ABSTRACT FROM AUTHOR]

Objective: The study aimed to evaluate fibroblast growth factor-21 levels in type 1 diabetes patients and its relationship with carotid intima-media thickness which is a marker of atherosclerosis. Patients and Methods: We recruited 39 patients with type 1 diabetes mellitus and 39 healthy controls. Blood samples for fibroblast growth factor-21, adiponectin and carboxymethyllysine were drawn from subjects after 8 hours fasting. Fasting blood glucose and hemoglobinA1c levels were obtained from patient records. Carotid intima media-thickness was measured via B-mode ultrasound by the same physician. Results: Median fibroblast growth factor-21 levels were 0.54 (0.10-10.69) ng/ml in type 1 diabetes patients, 0.42 (0.09-1.57) ng/ml in healthy controls (P=0.13). There was no correlation between serum fibroblast growth factor-21 levels and carotid intima-media thickness. Carboxymethyllysine levels were similar in both groups (P=0.86). Adiponectin level was 16336.7 ± 7338.7 ng/ml in type 1 diabetes patients, 13343.1 ± 5318.7 ng/ml in control group (P=0.04). Conclusion: Our study did not find any relation between serum fibroblast growth factor-21 levels and carotid intima-media thickness. Further researches with wider study population are needed. [ABSTRACT FROM AUTHOR]

Summary 1: The first article discusses a study comparing biodosimetry and physical dosimetry techniques for estimating radiation dose in emergency situations. The study found that physical dosimetry using smartphone components can estimate high-energy (gamma ray) exposure well, but overestimates x-ray exposure.Summary 2: The second article presents a cross-sectional study of suicides in Australia, focusing on substances detected during postmortem toxicology analyses. The study found that psychotropic medications and potentially intoxicating medications/drugs were found at high rates in both poisoning- and non-poisoning-related suicides.Summary 3: The third article examines the administration of Centruroides (scorpion) antivenom and investigates the rate of serious adverse events when the antivenom is given as a slow intravenous push. The study found that the administration of antivenom via slow intravenous push (sIVP) was safe and effective when given by trained staff. [Extracted from the article]

Introduction: Carbon monoxide (CO) is a colorless and odorless gas that is a leading cause of environmental poisoning in the USA with substantial mortality and morbidity. The mechanism of CO poisoning is complex and includes hypoxia, inflammation, and leukocyte sequestration in brain microvessel segments leading to increased reactive oxygen species. Another important pathway is the effects of CO on the mitochondria, specifically at cytochrome c oxidase, also known as Complex IV (CIV). One of the glaring gaps is the lack of rigorous experimental models that may recapitulate survivors of acute CO poisoning in the early phase. The primary objective of this preliminary study is to use our advanced swine platform of acute CO poisoning to develop a clinically relevant survivor model to perform behavioral assessment and MRI imaging that will allow future development of biomarkers and therapeutics. Methods: Four swine (10 kg) were divided into two groups: control (n = 2) and CO (n = 2). The CO group received CO at 2000 ppm for over 120 min followed by 30 min of re-oxygenation at room air for one swine and 150 min followed by 30 min of re-oxygenation for another swine. The two swine in the sham group received room air for 150 min. Cerebral microdialysis was performed to obtain semi real-time measurements of cerebral metabolic status. Following exposures, all surviving animals were observed for a 24-h period with neurobehavioral assessment and imaging. At the end of the 24-h period, fresh brain tissue (cortical and hippocampal) was immediately harvested to measure mitochondrial respiration. Results: While a preliminary ongoing study, animals in the CO group showed alterations in cerebral metabolism and cellular function in the acute exposure phase with possible sustained mitochondrial changes 24 h after the CO exposure ended. Conclusions: This preliminary research further establishes a large animal swine model investigating survivors of CO poisoning to measure translational metrics relevant to clinical medicine that includes a basic neurobehavioral assessment and post exposure cellular measures. [ABSTRACT FROM AUTHOR]

Objective The aim of this study was to assess the impact of hydroxocobalamin (OHCbl) infusion on arterial blood gas and oximetry values in patients with vasoplegic syndrome. Methods Blood samples collected from 95 patients receiving OHCbl infusion were assayed using the ABL90 FLEX Plus blood gas analyzer for the concentration of methemoglobin (MetHb), total hemoglobin (tHb), carboxyhemoglobin (COHb), arterial oxygen saturation (SaO2), arterial oxygen partial pressure (PaO2), and arterial carbon dioxide partial pressure (PaCO2). Interference of OHCbl on these variables was evaluated using the measured difference between the preinfusion and postinfusion samples. Results Blood MetHb (%) measured after the infusion of OHCbl (5g) were significantly higher than the baseline levels, with a median of 4.8 (IQR, 3.0−6.5) versus 1.0 (IQR, 1.0−1.2) (P <.001). Blood COHb (%) increased from a median of 1.3 (IQR, 1.0−1.8) to 1.7 (IQR, 1.3−2.2) (P <.001) following the OHCbl infusion. No differences were seen in median levels of tHb, PaO2, PaCO2, and SaO2 between pre- and post-OHCbl treatment. Conclusion The presence of OHCbl in blood clearly interfered with the oximetry measurements of the hemoglobin component fractions by falsely increasing the levels of MetHb and COHb. Blood levels of MetHb and COHb cannot be reliably determined by the co-oximetry when OHCbl is known or suspected. [ABSTRACT FROM AUTHOR]