No abstract available.
Animals ; Blood Platelets* ; Butylated Hydroxytoluene* ; Rats* ; Streptococcus* ; Thrombin*

Antibiotics were reported to be able to alter bacterial surface properties in subinhibitory concentrations (sub-MICs). The effects of sub-MICs of certain antibiotics on a bacterial surface property such as hemagglutination, as well as on the cell morphology were studied using Streptococcus gordonii and Staphylococcus aureus. The effect of sub-M1Cs of antibiotics on the binding of these bacteria to immobilized fibrinogen were also investigated. The MICs of antibiotics were determined by culturing S. gordonii and S. aureus in media supplemented with serially diluted drug solutions, and one-half the MIC was used as the sub-MIC of the drugs, unless stated otherwise. Sub-MICs of antibiotics did not affect bacterial agglutination of erythrocytes. Microscopic observation of S. gordonii grown at sub-MIC concentration of 0.02 ug/ml of amoxicillin revealed cell enlargement of 1.6 times those grown without the drug. When grown in the sub-MIC amount of 0.08 ug/ml of cefazolin, most S. gordonii cells were enlarged and elongated into rod-shape, resulting in 3 times the size of the cells grown without the antibiotic. The data from the fibrinogen-binding experiments showed that the binding of S. gordonii to immobilized fibrinogen was increased with all the B-lactam drugs tested; the binding of S. aureus to immobilized fibrinogen, on the other hand, was decreased with the same drugs. The results show that low concentrations of certain B-lactam antibiotics are able to cause alterations in cellular morphology of S. gordonii and affect the binding of S. gordonii and S. aureus to immobilized fibrinogen.
Agglutination ; Amoxicillin ; Anti-Bacterial Agents* ; Bacteria ; Cefazolin ; Cell Enlargement ; Erythrocytes ; Fibrinogen ; Hand ; Hemagglutination ; Staphylococcus aureus* ; Staphylococcus* ; Streptococcus gordonii* ; Streptococcus* ; Surface Properties*

No abstract available.
Cardiac Output* ; Ductus Arteriosus* ; Humans ; Infant, Newborn*

No abstract available.
Blood Flow Velocity* ; Humans ; Infant, Newborn*

Background: The risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission during the endemic phase may vary from that during the previous pandemic phase. We evaluated the risk of infection in a general population with laboratory-confirmed coronavirus disease 2019 (COVID-19) in a community setting in Korea. Materials and Methods: This study included 1,286 individuals who had been in contact with an index COVID-19 case between January 24, 2020, and June 30, 2022. Variables such as age, sex, nationality, place of contact, level of contact, the status of exposed cases, period, and level of mask-wearing were assessed. Results: Among 1,286 participants, 132 (10.30%) were confirmed to have COVID-19. With increasing age, the risk of the exposed persons contracting COVID-19 from index cases tended to increase (P <0.001), especially for people in their 70s (odds ratio, 1.24; 95% confidence interval, 1.11–1.40; P <0.001). We found an increasing trend in the risk of a COVID-19 exposed case becoming a secondary infection case (P <0.001) in long-term care facilities where the attack rate was high. Conclusion The risk of COVID-19 transmission is high in long-term care facilities where many older adults reside. Intensive management of facilities at risk of infection and strict mask-wearing of confirmed COVID-19 cases are necessary to prevent the risk of COVID-19 infection.

Background/Aims: Sedation has become a standard practice for patients undergoing gastrointestinal (GI) endoscopy. However, considering the serious cardiopulmonary adverse events associated with sedatives, it is important to identify patients at high risk. Machine learning can generate reasonable prediction for a wide range of medical conditions. This study aimed to evaluate the risk factors associated with sedation during GI endoscopy and develop a predictive model for hypoxia during endoscopy under sedation. Methods: This prospective observational study enrolled 446 patients who underwent sedative endoscopy at the Korea University Ansan Hospital. Clinical data were used as predictor variables to construct predictive models using the random forest method that is a machine learning algorithm. Results: Seventy-two of the 446 patients (16.1%) experienced life-threatening hypoxia requiring immediate medical intervention. Patients who developed hypoxia had higher body weight, body mass index (BMI), neck circumference, and Mallampati scores. Propofol alone and higher initial and total dose of propofol were significantly associated with hypoxia during sedative endoscopy. Among these variables, high BMI, neck circumference, and Mallampati score were independent risk factors for hypoxia. The area under the receiver operating characteristic curve for the random forest-based predictive model for hypoxia during sedative endoscopy was 0.82 (95% confidence interval, 0.79–0.86) and displayed a moderate discriminatory power. Conclusions High BMI, neck circumference, and Mallampati score were independently associated with hypoxia during sedative endoscopy. We constructed a model with acceptable performance for predicting hypoxia during sedative endoscopy.

BACKGROUND: Most morphometric studies of the airway have relied on plain radiographs or CT scan with their attendant limitations. We evaluated the length from vocal cord to carina and diameter of the trachea in adults who had no abnormality of the airway using three-dimensional chest CT scan and compared with demographic data. METHODS: We performed a multiplane reconstruction of the airway using axial, sagittal, and coronal slices (aged 18-87, 100 men, 100 women). We measured that the lengths from vocal cord to carina and the diameters (AP, anteroposterior; TR, transverse) of 50 mm above carina of the trachea. RESULTS: The lengths from vocal cord to carina was 130.2 +/- 11.4 mm in men and 119.5 +/- 10.5 mm in women. The AP and TR diameters of the trachea at 50 mm above carina were men; 18.0 +/- 2.4 mm, 17.2 +/- 2.6 mm, women; 14.4 +/- 2.0 mm, 14.4 +/- 1.9 mm, respectively. The correlation between airway length and age and height was statically significant in men and women but less clinically significant. The correlation between diameter of trachea and height was only statically significant in men but less clinically significant. CONCLUSIONS: This study suggests that these measured data are helpful for the endotracheal intubation and endotracheal tube placement in airway management.
Adult ; Airway Management ; Female ; Humans ; Intubation, Intratracheal ; Male ; Thorax ; Trachea ; Vocal Cords

BACKGROUND: Neonatal coagulation systems are quantitatively deficient and immature. Clinical experience, however, does not indicate an increased risk of excessive bleeding associated with surgical procedures in the neonatal period. Moreover, the coagulatory function of neonates by thromboelastography (TEG) is not well known. In this study, we used TEG to assess the coagulation system of term neonates and their pregnant mother to obtain TEG variables of term neonates, and to identify differences between the coagulation systems of term neonates and pregnant mother. METHODS: TEG was performed on 30 pregnant women that underwent Cesarean section delivery using native whole blood, and on their 30 neonates delivered by Cesarean section using umbilical cord venous blood. Blood samples were collected immediately after delivery and TEGs were measured. The TEG variables included reaction time (R), clot formation time (K), maximum amplitude (MA), alpha angle, TEG coagulation index and percentage reduction in MA at 30 minutes (LY30) and 60 minutes (LY60). RESULTS: TEG measurements in neonates were R (mm): 9.7 +/- 5.3 (5.0-18.5), K (mm): 7.5 +/- 2.9 (4.0-12.5), MA (mm): 42.4 +/- 7.8 (25-53.0), alpha angle (o): 46.5 +/- 15.1 (31.0-64.5), TEG index: -0.3 +/- 1.3 (-2.58-+ 1.78), LY30 (%): 30.0 +/- 21.4 (1.5-62.5), LY60 (%): 43.4 +/- 24.7 (5.0-64.5). The R, MA and TEG coagulation indexes were significantly lower in neonates than in their pregnant mother (P <0.05). However, LY60 was significantly higher in the neonates than in the pregnant mother (P <0.05). CONCLUSIONS: We obtained TEG measurements in neonates immediately after Cesarean section delivery, and found differences in the TEG-defined coagulation systems of term neonates and their pregnant mother.
Cesarean Section* ; Female ; Hemorrhage ; Humans ; Infant, Newborn* ; Mothers ; Pregnancy ; Pregnant Women ; Reaction Time ; Thrombelastography ; Umbilical Cord

BACKGROUND: Hypotension and bradycardia in the propofol and alfentanil anesthesia are common during induction and maintenance. Ephedrine has been used to attenuate hypotension and bradycardia in the propofol and alfentanil anesthesia. We designed this study to determine whether propofol and alfentanil anesthesia could affect the blood pressure and heart rate response to intravenous ephedrine when compared with the awake state. METHODS: Forty patients of ASA physical status 1 or 2 were assigned to one of two groups (Awake vs Propofol-alfentanil [P-A] group). Each patients received ephedrine 0.15 mg/kg after assessment of baseline hemodynamic values. In the awake patients, ephedrine were administered after hemodynamic parameters are stabilized. If hemodynamic parameters are stabilized after intubation, ephedrine were administered in the propofol-alfentanil anesthesia patients. The changes in systolic/diastolic blood pressure (SBP/DBP), mean blood pressure (MBP), and heart rate (HR) were recorded every one minute for 10 minutes. RESULTS: Ephedrine increased the heart rate significantly in Awake group but not in P-A group. In the P-A group, 3 min after the administration of ephedrine, MBP increased 25.3%. In Awake group, 2 min after the administration of ephedrine, MBP increased only 6.3%. CONCLUSIONS: We conclude that propofol and alfentanil anesthesia augments the BP response to intravenous ephedrine but not HR.
Alfentanil ; Anesthesia ; Blood Pressure ; Bradycardia ; Ephedrine ; Heart ; Heart Rate ; Hemodynamics ; Humans ; Hypotension ; Intubation ; Propofol

BACKGROUND: Hypotension and bradycardia in the propofol and alfentanil anesthesia are common during induction and maintenance. Ephedrine has been used to attenuate hypotension and bradycardia in the propofol and alfentanil anesthesia. We designed this study to determine whether propofol and alfentanil anesthesia could affect the blood pressure and heart rate response to intravenous ephedrine when compared with the awake state. METHODS: Forty patients of ASA physical status 1 or 2 were assigned to one of two groups (Awake vs Propofol-alfentanil [P-A] group). Each patients received ephedrine 0.15 mg/kg after assessment of baseline hemodynamic values. In the awake patients, ephedrine were administered after hemodynamic parameters are stabilized. If hemodynamic parameters are stabilized after intubation, ephedrine were administered in the propofol-alfentanil anesthesia patients. The changes in systolic/diastolic blood pressure (SBP/DBP), mean blood pressure (MBP), and heart rate (HR) were recorded every one minute for 10 minutes. RESULTS: Ephedrine increased the heart rate significantly in Awake group but not in P-A group. In the P-A group, 3 min after the administration of ephedrine, MBP increased 25.3%. In Awake group, 2 min after the administration of ephedrine, MBP increased only 6.3%. CONCLUSIONS: We conclude that propofol and alfentanil anesthesia augments the BP response to intravenous ephedrine but not HR.
Alfentanil ; Anesthesia ; Blood Pressure ; Bradycardia ; Ephedrine ; Heart ; Heart Rate ; Hemodynamics ; Humans ; Hypotension ; Intubation ; Propofol