BACKGROUND: Although smoking rates have been declining worldwide, new types of tobacco products have been gradually spreading in recent years, especially in Japan, where heated tobacco products (HTPs) users are rapidly increasing. Oxidative stress caused by reactive oxygen species (ROS) is one of the causes of smoking-induced carcinogenesis, respiratory diseases, and cardiovascular diseases. However, information on the amount of ROS contained in mainstream smoke from HTPs is limited. In this study, we measured the amount of ROS generated from HTPs to evaluate the oxidative stress-related toxicity of HTPs. METHODS: IQOS ILUMA, glo hyper+, and Ploom X ADVANCED were used as the HTP devices. Mainstream smoke was collected from each HTP according to Health Canada Intense regime (smoke volume, 55 mL; smoke duration, 2 s). The collected ROS were reacted with 2,7'-dichlorodihydrofluorescein reagents, and the amount of ROS was calculated as H₂O₂ equivalent from the fluorescence intensity obtained. RESULTS: The ROS in the mainstream smoke from IQOS ILUMA, glo hyper+ (high-temperature mode), and Ploom X ADVANCED was found to be 48.8 ± 8.6, 86.6 ± 12.6, and 40.8 ± 5.7 nmol H₂O₂/stick, respectively (n = 6, mean ± standard deviation), with the highest being from glo hyper+ (high-temperature mode). The amount of ROS was significantly higher in the high-temperature mode of glo hyper+ than in the standard mode of glo hyper+. Additionally, the estimated amount of ROS from smoking 20 heated sticks per day (674-2160 nmol H₂O₂/day) was equivalent to 2.2-96 times the amount of daily exposure to ROS in the urban atmosphere (approximately 22-300 nmol H₂O₂/day). CONCLUSIONS We found that ROS is generated from HTPs of different devices. This study suggests that HTPs users may be exposed to much more ROS than they are exposed to in normal life.
Reactive Oxygen Species/analysis* ; Tobacco Products/analysis* ; Smoke/analysis* ; Hot Temperature ; Japan ; Oxidative Stress

A method for determining volatile organic compounds (VOCs) emitted from medical molecular sieve oxygen concentrators was developed using thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). The oxygen concentrator gas was sampled at a flow rate of 0.5 L/min through a branched sampling system onto Tenax GR/carbopack B adsorption tubes. The adsorbed compounds were desorbed and introduced using a programmed temperature vaporization inlet system, followed by chromatographic separation on an SH-I-624Sil MS column. Four VOCs (BHT-Q, PTBP, BHT-quinol, and EHB) were detected in the medical oxygen concentrator using this method. Calibration curves for these compounds exhibited excellent linearity ( R ²>0.99) within the range of 3~100 ng. With a sampling volume of 20 L, the detection limit of the four VOCs ranged from 0.003 9 to 0.022 2 μg/m ³. Spike recovery rates for the four VOCs were between 95% and 115%, with relative standard deviations (RSDs) below 5% ( n=6). The method is simple, rapid, highly sensitive, and accurate, making it suitable for VOCs detection in medical molecular sieve oxygen concentrators.
Volatile Organic Compounds/analysis* ; Gas Chromatography-Mass Spectrometry/methods* ; Oxygen

OBJECTIVES: To study the clinical value of intestinal regional oxygen saturation (rSO₂) and C-reactive protein (CRP) in the diagnosis of necrotizing enterocolitis (NEC) in preterm infants. METHODS: A prospective observational study was conducted among the preterm infants who were hospitalized in Children's Hospital Affiliated to Anhui Medical University, from October 2020 to December 2021, with 22 infants in the NEC group and 35 infants in the non-NEC group. Intestinal rSO₂ was monitored 24 hours after a confirmed diagnosis of NEC in the NEC group, and serum CRP levels were measured before anti-infection therapy. In the non-NEC group, intestinal rSO₂ monitoring and serum CRP level measurement were performed at the corrospording time points. The two groups were compared in terms of intestinal rSO₂ and serum CRP level. The receiver operating characteristic (ROC) curve was used to analyze the value of intestinal rSO₂ alone, serum CRP alone, and intestinal rSO₂ combined with CRP in the diagnosis of NEC in preterm infants. RESULTS: Compared with the non-NEC group, the NEC group had a significantly lower level of intestinal rSO₂ (P<0.05) and a higher serum CRP level (P<0.05). The ROC curve analysis showed that intestinal rSO₂ had an optimal cut-off value of 50.75% in the diagnosis of NEC in preterm infants, with a sensitivity of 81.8%, a specificity of 85.7%, and an area under the ROC curve (AUC) of 89.4%; CRP had an optimal cut-off value of 12.05 mg/L in the diagnosis of NEC in preterm infant, with a sensitivity of 72.7%, a specificity of 74.3%, and an AUC of 74.8%; intestinal rSO₂ combined with CRP had a sensitivity of 90.9%, a specificity of 77.1%, and an AUC of 91.9% in the diagnosis of NEC. The AUC of intestinal rSO₂ alone in the diagnosis NEC was higher than that of CRP (P<0.05). There was no significant difference in the AUC between intestinal rSO₂ alone and intestinal rSO₂ combined with CRP (P>0.05). CONCLUSIONS The value of intestinal rSO₂ in the diagnosis NEC is higher than that of CRP, and is equivalent to that of the combination of intestinal rSO₂ and CRP in preterm infants.
Infant ; Child ; Infant, Newborn ; Humans ; Enterocolitis, Necrotizing/diagnosis* ; Infant, Premature ; C-Reactive Protein/analysis* ; Oxygen Saturation ; Infant, Newborn, Diseases

Oxygen reserve index (ORI) is a novel dimensionless index used for noninvasive, real-time, and continuous monitoring of oxygenation, and ORI value ranges from 0 to 1, which reflects the range of 100-200 mmHg for arterial partial pressure of oxygen. ORI combined with pulse oximetry may help to accurately adjust the concentration of inspired oxygen and prevent hyperoxemia and hypoxemia. ORI is suitable for various clinical situations, and the medical staff should master this novel parameter and use it properly to assess the oxygenation of patients. In addition, several limitations of ORI should be noticed during clinical application.
Humans ; Oxygen ; Blood Gas Analysis ; Oxygen Inhalation Therapy ; Oximetry ; Hypoxia/therapy*

BACKGROUND: The 2019 novel coronavirus has caused the outbreak of the acute respiratory disease in Wuhan, Hubei Province of China since December 2019. This study was performed to analyze the clinical characteristics of patients who succumbed to and who recovered from 2019 novel coronavirus disease (COVID-19). METHODS: Clinical data were collected from two tertiary hospitals in Wuhan. A retrospective investigation was conducted to analyze the clinical characteristics of fatal cases of COVID-19 (death group) and we compare them with recovered patients (recovered group). Continuous variables were analyzed using the Mann-Whitney U test. Categorical variables were analyzed by χ test or Fisher exact test as appropriate. RESULTS: Our study enrolled 109 COVID-19 patients who died during hospitalization and 116 recovered patients. The median age of the death group was older than the recovered group (69 [62, 74] vs. 40 [33, 57] years, Z = 9.738, P < 0.001). More patients in the death group had underlying diseases (72.5% vs. 41.4%, χ = 22.105, P < 0.001). Patients in the death group had a significantly longer time of illness onset to hospitalization (10.0 [6.5, 12.0] vs. 7.0 [5.0, 10.0] days, Z = 3.216, P = 0.001). On admission, the proportions of patients with symptoms of dyspnea (70.6% vs. 19.0%, χ = 60.905, P < 0.001) and expectoration (32.1% vs. 12.1%, χ = 13.250, P < 0.001) were significantly higher in the death group. The blood oxygen saturation was significantly lower in the death group (85 [77, 91]% vs. 97 [95, 98]%, Z = 10.625, P < 0.001). The white blood cell (WBC) in death group was significantly higher on admission (7.23 [4.87, 11.17] vs. 4.52 [3.62, 5.88] ×10/L, Z = 7.618, P < 0.001). Patients in the death group exhibited significantly lower lymphocyte count (0.63 [0.40, 0.79] vs. 1.00 [0.72, 1.27] ×10/L, Z = 8.037, P < 0.001) and lymphocyte percentage (7.10 [4.45, 12.73]% vs. 23.50 [15.27, 31.25]%, Z = 10.315, P < 0.001) on admission, and the lymphocyte percentage continued to decrease during hospitalization (7.10 [4.45, 12.73]% vs. 2.91 [1.79, 6.13]%, Z = 5.242, P < 0.001). Alanine transaminase (22.00 [15.00, 34.00] vs. 18.70 [13.00, 30.38] U/L, Z = 2.592, P = 0.010), aspartate transaminase (34.00 [27.00, 47.00] vs. 22.00 [17.65, 31.75] U/L, Z = 7.308, P < 0.001), and creatinine levels (89.00 [72.00, 133.50] vs. 65.00 [54.60, 78.75] μmol/L, Z = 6.478, P < 0.001) were significantly higher in the death group than those in the recovered group. C-reactive protein (CRP) levels were also significantly higher in the death group on admission (109.25 [35.00, 170.28] vs. 3.22 [1.04, 21.80] mg/L, Z = 10.206, P < 0.001) and showed no significant improvement after treatment (109.25 [35.00, 170.28] vs. 81.60 [27.23, 179.08] mg/L, Z = 1.219, P = 0.233). The patients in the death group had more complications such as acute respiratory distress syndrome (ARDS) (89.9% vs. 8.6%, χ = 148.105, P < 0.001), acute cardiac injury (59.6% vs. 0.9%, χ = 93.222, P < 0.001), acute kidney injury (18.3% vs. 0%, χ = 23.257, P < 0.001), shock (11.9% vs. 0%, χ = 14.618, P < 0.001), and disseminated intravascular coagulation (DIC) (6.4% vs. 0%, χ = 7.655, P = 0.006). CONCLUSIONS Compared to the recovered group, more patients in the death group exhibited characteristics of advanced age, pre-existing comorbidities, dyspnea, oxygen saturation decrease, increased WBC count, decreased lymphocytes, and elevated CRP levels. More patients in the death group had complications such as ARDS, acute cardiac injury, acute kidney injury, shock, and DIC.
Adult ; Aged ; Aged, 80 and over ; Betacoronavirus ; C-Reactive Protein ; analysis ; Coronavirus Infections ; complications ; mortality ; Female ; Humans ; Male ; Middle Aged ; Oxygen ; blood ; Pandemics ; Pneumonia, Viral ; complications ; mortality ; Retrospective Studies

BACKGROUND: Beyond its current function as a rescue therapy in acute respiratory distress syndrome (ARDS), extracorporeal membrane oxygenation (ECMO) may be applied in ARDS patients with less severe hypoxemia to facilitate lung protective ventilation. The purpose of this study was to evaluate the efficacy of extended ECMO use in ARDS patients. METHODS: This study reviewed 223 adult patients who had been admitted to the intensive care units of 11 hospitals in Korea and subsequently treated using ECMO. Among them, the 62 who required ECMO for ARDS were analyzed. The patients were divided into two groups according to pre-ECMO arterial blood gas: an extended group (n=14) and a conventional group (n=48). RESULTS: Baseline characteristics were not different between the groups. The median arterial carbon dioxide tension/fraction of inspired oxygen (FiO2) ratio was higher (97 vs. 61, p<0.001) while the median FiO2 was lower (0.8 vs. 1.0, p<0.001) in the extended compared to the conventional group. The 60-day mortality was 21% in the extended group and 54% in the conventional group (p=0.03). Multivariate analysis indicated that the extended use of ECMO was independently associated with reduced 60-day mortality (odds ratio, 0.10; 95% confidence interval, 0.02–0.64; p=0.02). Lower median peak inspiratory pressure and median dynamic driving pressure were observed in the extended group 24 hours after ECMO support. CONCLUSION: Extended indications of ECMO implementation coupled with protective ventilator settings may improve the clinical outcome of patients with ARDS.
Adult ; Anoxia ; Carbon Dioxide ; Extracorporeal Membrane Oxygenation ; Humans ; Intensive Care Units ; Korea ; Lung ; Mortality ; Multicenter Studies as Topic ; Multivariate Analysis ; Oxygen ; Respiration, Artificial ; Respiratory Distress Syndrome, Adult ; Retrospective Studies ; Ventilation ; Ventilators, Mechanical

PURPOSE: We investigated the characteristics of lung allocation and outcomes of lung transplant (LTx) according to the Korean urgency status. MATERIALS AND METHODS: LTx registration in the Korean Organ Transplantation Registry (KOTRY) began in 2015. From 2015 to June 2017, 86 patients who received LTx were enrolled in KOTRY. After excluding one patient who received a heart-lung transplant, 85 were included. Subjects were analyzed according to the Korean urgency status. RESULTS: Except for Status 0, urgency status was classified based on partial pressure of oxygen in arterial blood gas analysis and functional status in 52 patients (93%). The wait time for lung allograft was well-stratified by urgency (Status 0, 46.5±59.2 days; Status 1, 104.4±98.2 days; Status 2 or 3, 132.2±118.4 days, p=0.009). Status 0 was associated with increased operative times and higher intraoperative blood transfusion. Status 0 was associated with prolonged extracorporeal membrane oxygenation use, postoperative bleeding, and longer mechanical ventilation after operation. Survival of Status 0 patients seemed worse than that of non-Status 0 patients, although differences were not significant. CONCLUSION: The Korean urgency classification for LTx is determined by using very limited parameters and may not be a true reflection of urgency. Status 0 patients seem to have poor outcomes compared to the other urgency status patients, despite having the highest priority for donor lungs. Further multi-center and nationwide studies are needed to revise the lung allocation system to reflect true urgency and provide the best benefit of lung transplantation.
Allografts ; Blood Gas Analysis ; Blood Transfusion ; Classification ; Extracorporeal Membrane Oxygenation ; Hemorrhage ; Humans ; Lung Transplantation ; Lung ; Operative Time ; Organ Transplantation ; Oxygen ; Partial Pressure ; Respiration, Artificial ; Tissue Donors ; Transplants

In order to investigate the antioxidant effect of alkylhydroxide peroxidase (ahpC) of Helicobacter pylori (H. pylori) 26695, an ahpC-deficient mutant (H. pylori 26695 ahpC::cat) was generated. ahpC-deficient mutant was grown slowly at lower pressure of oxygen (5% oxygen) compared to the H. pylori 26695. Whole cell proteins isolated form H. pylori 26695 and H. pylori 26695 ahpC::cat were analyzed by MALDI-TOF and tandem-MS. The expression of 15 proteins, including Ppa, HypB, GrpE, Elp, RecA, GroES, Mda66, RibE, NapA, GlnA, BioB, TrxB, Tsf, FumC and Icd, was more than doubled in H. pylori 26695 ahpC::cat. Production of 10 proteins such as UreG, FabE, Adk, Pnp, OorC, AtpA, AtpD, Nqq3, Pfr, and TagD decreased below 50% in H. pylori 26695 ahpC::cat compared to the H. pylori 26695. In microarray analysis, 9 genes including sul1, amiE, frxA, fecA, hyuA, and katA increased in transcription level in H. pylori 26695 ahpC::cat compared to H. pylori 26695. A total of 24 genes, including flaB, protein kinase C inhibitor, cag16, pabC, and sabA, reduced in transcription. 27 genes, including HP0889, showed common expression changes in ahpC, katA, and sodB-deficient mutations. As a result of this study, there were not many genes whose expression was commonly changed by the deletion of each of the three major antioxidant enzymes of H. pylori. These results showed the functions and regulation of the three antioxidant enzymes were different in H. pylori.
Antioxidants ; Helicobacter pylori ; Helicobacter ; Microarray Analysis ; Oxygen ; Peroxidase ; Protein Kinase C ; Proteome ; Ribes

BACKGROUND: Postoperative desaturation in older individuals is rarely addressed in the literature. The objective of this retrospective study was to investigate whether a preoperative spirometric test and arterial blood gas analysis (ABGA) might predict postoperative desaturation after spinal anesthesia in extreme older patients.METHODS: The medical records of 399 patients (age ≥ 80 yrs) who were administered spinal anesthesia for a femur neck fracture surgery were retrospectively reviewed. Early postoperative desaturation was defined as a reduction of oxygen saturation (SpO₂) below 90% within 3 days of surgery, despite O₂ supply via a nasal prong. Binary logistic regression analysis was used to identify predictors of early postoperative desaturation.RESULTS: The incidence of postoperative desaturation was 12.5%. Major morbidity rate was significantly higher in the desaturation group (n = 50) than that in the non-desaturation group (n = 349) (14% vs. 3.2%, P = 0.001) with more frequent postoperative stays in the intensive care unit (22% vs. 12%, P = 0.004). In a binary logistic regression analysis, preoperative ratio of arterial oxygen partial pressure to fractional inspired oxygen (PaO₂/FiO₂ ratio) (OR, 0.972; 95% CI 0.952–0.993; P = 0.010) and history of cardiovascular disease (OR, 2.127; 95% CI 1.004–4.507; P = 0.049) predicted postoperative desaturation.CONCLUSIONS: Preoperative PaO₂/FiO₂ ratio, but not preoperative spirometry, was predictive of the postoperative desaturation in older patients after being administered spinal anesthesia for femur fracture surgery. Based on our results, preoperative ABGA may be helpful in predicting early postoperative desaturation in these patients.
Anesthesia, Spinal ; Blood Gas Analysis ; Cardiovascular Diseases ; Femoral Neck Fractures ; Femur ; Humans ; Incidence ; Intensive Care Units ; Logistic Models ; Medical Records ; Oxygen ; Partial Pressure ; Retrospective Studies ; Spirometry

OBJECTIVE: To investigate the development and characterizations of the hepatocytes isolated from fetal ovine and to determine the effect of hypoxia on their growth and metabolism. METHODS: Fresh hepatocytes were isolated from the liver of fetal ovine at late gestation, cultured in specific media, and exposed to normoxia (21% O2) or hypoxia (2% O2). The cellular characteristics and population purity were identified by immunocytochemistry and flow cytometry (FCM). The effects of hypoxia on cell cycle and apoptosis of the hepatocytes were evaluated by FCM, whereas the cellular ultrastructure changes were examined with a transmission electron microscope. RESULTS: The cell purity of hepatocytes was over 95%. Under hypoxia exposure, the hepatocytes showed a gradual increase in proportion at the S phase and in proliferative index, followed with a compatible increase in apoptosis and progressively decreased cell viability. Additionally, the organelles of the hepatocytes demonstrated dramatic changes, including swelling of mitochondria, disorder in cristae arrangement, expansion of endoplasmic reticulum, and a large number of circular lipid droplets emerging in the cytoplasm. CONCLUSION Fetal ovine hepatocytes could be primarily cultured in a short-term culture system with a high purity of over 95% and with their preserved original characteristics. Hypoxia could induce changes in ultrastructural and inhibit the proliferation of cultured fetal ovine hepatocytes through apoptotic mechanisms.
Anaerobiosis ; Animals ; Cell Culture Techniques ; Fetus ; physiology ; Hepatocytes ; physiology ; Oxygen ; analysis ; Sheep ; physiology