Use of vasopressors to manage spinal anesthesia-induced hypotension during cesarean delivery.

Cesarean sections are commonly performed under spinal anesthesia, which can lead to hypotension, adversely affecting maternal and fetal outcomes. Hypotension following spinal anesthesia is generally defined as a blood pressure of 80-90% below the baseline value. Various strategies have been implemented to reduce the incidence of spinal anesthesia-induced hypotension. The administration of vasopressors is a crucial method for preventing and treating hypotension. In the past decade, phenylephrine, a primarily alpha-adrenergic agonist, has been the preferred vasopressor for cesarean sections. Recently, norepinephrine, a potent alpha-agonist with modest beta-agonist activity, has gained popularity owing to its advantages over phenylephrine. Vasopressors can be administered via a bolus or continuous infusion. Although administering boluses alone is simpler in a clinical setting, continuous prophylactic infusion initiated immediately after spinal anesthesia is more effective in reducing the incidence of hypotension. Tailoring the infusion dose based on the patient's body weight and adjusting the rate in response to blood pressure changes, in addition to using a prophylactic or rescue bolus, helps reduce blood pressure variability during cesarean sections under spinal anesthesia until neonatal delivery.

Beneficial Effect of Rapamycin on Liver Fibrosis in a Mouse Model (C57bl/6 Mouse).

BACKGROUND: Liver fibrosis is a chronic inflammatory disease that progresses and has a high mortality rate. This study was performed to investigate the protective effect of rapamycin on experimentally induced chronic liver injury in mice models using both biochemical parameters of liver function enzymes. METHODS: Twenty-four mice were divided randomly into 4 equal groups: [1] the normal group, n = 6; [2] the liver fibrosis (LF) group, n = 6; [3] the LF with the treatment of rapamycin group, n = 6; [4] the LF with the treatment of silimaryn, n = 6. RESULTS: In the group receiving oral administration of rapamycin, aspartate aminotransferase, alanine aminotransferase, urea, and creatinine were found to significantly decrease compared to the liver fibrosis group. Rapamycin, in the orally administered group, demonstrated a statistically significant decrease in the expression of interleukin (IL) 10, IL-1B, inducible nitric oxide synthase, and tumor necrosis factor alpha compared to the liver fibrosis group. CONCLUSIONS: In this study, we explored the potential therapeutic effects of rapamycin on liver fibrosis in an animal model.

The Hospitalist-Oncologist co-ManagemEnt (HOME) system improves hospitalization outcomes of patients with cancer.

BACKGROUND: The hospitalist system has been introduced to improve the quality and safety of inpatient care. As its effectiveness has been confirmed in previous studies, the hospitalist system is spreading in various fields. However, few studies have investigated the feasibility and value of hospitalist-led care of patients with cancer in terms of quality and safety measures. This study aimed to evaluate the efficacy of the Hospitalist-Oncologist co-ManagemEnt (HOME) system. METHODS: Between January 1, 2019, and January 31, 2021, we analyzed 591 admissions before and 1068 admissions after the introduction of HOME system on January 1, 2020. We compared the length of stay and the types and frequencies of safety events between the conventional system and the HOME system, retrospectively. We also investigate rapid response system activation, cardiopulmonary resuscitation, unplanned intensive care unit transfer, all-cause in-hospital mortality, and 30-day re-admission or emergency department visits. RESULTS: The average length of stay (15.9 days vs. 12.9 days, P < 0.001), frequency of safety events (5.6% vs. 2.8%, P = 0.006), rapid response system activation (7.3% vs. 2.2%, P < 0.001) were significantly reduced after the HOME system introduction. However, there was no statistical difference in frequencies of cardiopulomonary resuscitation and intensive care unit transfer, all-cause in-hospital morality, 30-day unplanned re-admission or emergency department visits. CONCLUSIONS: The study suggests that the HOME system provides higher quality of care and safer environment compared to conventional oncologist-led team-based care, and the efficiency of the medical delivery system could be increased by reducing the hospitalization period without increase in 30-day unplanned re-admission.

The neurocognitive role of working memory load when Pavlovian motivational control affects instrumental learning.

Research suggests that a fast, capacity-limited working memory (WM) system and a slow, incremental reinforcement learning (RL) system jointly contribute to instrumental learning. Thus, situations that strain WM resources alter instrumental learning: under WM loads, learning becomes slow and incremental, the reliance on computationally efficient learning increases, and action selection becomes more random. It is also suggested that Pavlovian learning influences people's behavior during instrumental learning by providing hard-wired instinctive responses including approach to reward predictors and avoidance of punishment predictors. However, it remains unknown how constraints on WM resources affect instrumental learning under Pavlovian influence. Thus, we conducted a functional magnetic resonance imaging (fMRI) study (N = 49) in which participants completed an instrumental learning task with Pavlovian-instrumental conflict (the orthogonalized go/no-go task) both with and without extra WM load. Behavioral and computational modeling analyses revealed that WM load reduced the learning rate and increased random choice, without affecting Pavlovian bias. Model-based fMRI analysis revealed that WM load strengthened RPE signaling in the striatum. Moreover, under WM load, the striatum showed weakened connectivity with the ventromedial and dorsolateral prefrontal cortex when computing reward expectations. These results suggest that the limitation of cognitive resources by WM load promotes slow and incremental learning through the weakened cooperation between WM and RL; such limitation also makes action selection more random, but it does not directly affect the balance between instrumental and Pavlovian systems.

Development of a Bispectral index score prediction model based on an interpretable deep learning algorithm.

BACKGROUND: Proper maintenance of hypnosis is crucial for ensuring the safety of patients undergoing surgery. Accordingly, indicators, such as the Bispectral index (BIS), have been developed to monitor hypnotic levels. However, the black-box nature of the algorithm coupled with the hardware makes it challenging to understand the underlying mechanisms of the algorithms and integrate them with other monitoring systems, thereby limiting their use. OBJECTIVE: We propose an interpretable deep learning model that forecasts BIS values 25 s in advance using 30 s electroencephalogram (EEG) data. MATERIAL AND METHODS: The proposed model utilized EEG data as a predictor, which is then decomposed into amplitude and phase components using fast Fourier Transform. An attention mechanism was applied to interpret the importance of these components in predicting BIS. The predictability of the model was evaluated on both regression and binary classification tasks, where the former involved predicting a continuous BIS value, and the latter involved classifying a dichotomous status at a BIS value of 60. To evaluate the interpretability of the model, we analyzed the attention values expressed in the amplitude and phase components according to five ranges of BIS values. The proposed model was trained and evaluated using datasets collected from two separate medical institutions. RESULTS AND CONCLUSION: The proposed model achieved excellent performance on both the internal and external validation datasets. The model achieved a root-mean-square error of 6.614 for the regression task, and an area under the receiver operating characteristic curve of 0.937 for the binary classification task. Interpretability analysis provided insight into the relationship between EEG frequency components and BIS values. Specifically, the attention mechanism revealed that higher BIS values were associated with increased amplitude attention values in high-frequency bands and increased phase attention values in various frequency bands. This finding is expected to facilitate a more profound understanding of the BIS prediction mechanism, thereby contributing to the advancement of anesthesia technologies.

Effect of Active Surgical Co-Management by Medical Hospitalists in Urology Inpatient Care: A Retrospective Cohort Study.

PURPOSE: This study aimed to evaluate the use of active surgical co-management (SCM) by medical hospitalists for urology inpatient care. MATERIALS AND METHODS: Since March 2019, a hospitalist-SCM program was implemented at a tertiary-care medical center, and a retrospective cohort study was conducted among co-managed urology inpatients. We assessed the clinical outcomes of urology inpatients who received SCM and compared passive SCM (co-management of patients by hospitalists only on request; March 2019 to June 2020) with active SCM (co-management of patients based on active screening by hospitalists; July 2020 to October 2021). We also evaluated the perceptions of patients who received SCM toward inpatient care quality, safety, and subjective satisfaction with inpatient care at discharge or when transferred to other wards. RESULTS: We assessed 525 patients. Compared with the passive SCM group (n=205), patients in the active SCM group (n=320) required co-management for a significantly shorter duration (p=0.012) and tended to have a shorter length of stay at the urology ward (p=0.062) and less frequent unplanned readmissions within 30 days of discharge (p=0.095) while triggering significantly fewer events of rapid response team activation (p=0.002). No differences were found in the proportion of patients transferred to the intensive care unit, in-hospital mortality rates, or inpatient care questionnaire scores. CONCLUSION: Active surveillance and co-management of urology inpatients by medical hospitalists can improve the quality and efficacy of inpatient care without compromising subjective inpatient satisfaction.

Effect of intraoperative blood transfusion on inflammatory response in parturients with placenta previa undergoing cesarean section: A prospective observational study.

Background: The neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), and red cell distribution width (RDW) have been reported as useful biomarkers for evaluating inflammation and a predictor of surgical prognosis. Although there have been recent reports that transfusion may affect inflammatory responses, studies on the post-transfusion inflammatory response in parturients are rare. Therefore, this study aimed to observe changes in inflammatory response after transfusion during cesarean section (C-sec) through NLR, PLR, and RDW. Methods: Parturients aged 20-50 years who underwent C-sec under general anesthesia due to placenta previa totalis from March 4, 2021, to June 10, 2021 were participated in this prospective observational study. We compared postoperative NLR, PLR, and RDW between the transfusion and non-transfusion groups. Results: A total of 53 parturients were included in this study, of which 31 parturients received intraoperative transfusions during C-sec. There were no significant difference in preoperative NLR (3.6 vs. 3.4, p = 0.780), PLR (132.8 vs. 111.3, p = 0.108), and RDW (14.2 vs. 13.6, p = 0.062) between the two groups. However, postoperative NLR was significantly higher in the transfusion group than in the non-transfusion group (12.2 vs. 6.8, p < 0.001). Postoperative RDW was significantly higher in the transfusion group than in the non-transfusion group (14.6 vs. 13.9, p = 0.002) whereas postoperative PLR was not significantly different between the two groups (108.0 vs. 117.4, p = 0.885). Conclusions: Postoperative NLR and RDW, the inflammatory biomarkers, were significantly higher in the transfused C-sec parturients. These results suggest a significant association between postoperative inflammatory response and transfusion in obstetric practice.

Association of upper airway bacterial microbiota and asthma: systematic review.

Individual studies have suggested that upper airway dysbiosis may be associated with asthma or its severity. We aimed to systematically review studies that evaluated upper airway bacterial microbiota in relation to asthma, compared to nonasthmatic controls. Searches used MEDLINE, Embase, and Web of Science Core Collection. Eligible studies included association between asthma and upper airway dysbiosis; assessment of composition and diversity of upper airway microbiota using 16S rRNA or metagenomic sequencing; upper airway samples from nose, nasopharynx, oropharynx or hypopharynx. Study quality was assessed and rated using the Newcastle-Ottawa scale. A total of 249 publications were identified; 17 in the final analysis (13 childhood asthma and 4 adult asthma). Microbiome richness was measured in 6 studies, species diversity in 12, and bacterial composition in 17. The quality of evidence was good and fair. The alpha-diversity was found to be higher in younger children with wheezing and asthma, while it was lower when asthmatic children had rhinitis or mite sensitization. In children, Proteobacteria and Firmicutes were higher in asthmatics compared to controls (7 studies), and Moraxella, Streptococcus, and Haemophilus were predominant in the bacterial community. In pooled analysis, nasal Streptococcus colonization was associated with the presence of wheezing at age 5 (p = 0.04). In adult patients with asthma, the abundance of Proteobacteria was elevated in the upper respiratory tract (3 studies). Nasal colonization of Corynebacterium was lower in asthmatics (2 studies). This study demonstrates the potential relationships between asthma and specific bacterial colonization in the upper airway in adult and children with asthma.

Effect of outpatient physician involvement on the physician orders for life-sustaining treatment completed by hospitalists: a cross-sectional study.

BACKGROUND: Hospitalists are becoming increasingly involved in end-of-life (EOL) care decision making. They participate in the completion of physician orders for life-sustaining treatment (POLST) for patients who have not yet decided whether to proceed with life-sustaining treatment (LST) at the EOL. However, hospitalists are not physicians who have continuously treated patients in outpatient settings; hence, the continuity of care may be poor. We aimed to analyze the effect of outpatient physician involvement on the POLST completed by hospitalists. METHODS: A retrospective cohort study was conducted in patients aged 18 years or older treated by hospitalists who completed POLST at Seoul National University Bundang Hospital from February 2018 to March 2020. The clinical and sociodemographic data were obtained through a medical chart review, and the differences in the characteristics of POLST were analyzed depending on the status of outpatient physician involvement. RESULTS: A total of 3,533 POLST forms were written, of which 175 (5.22%) were completed by the hospitalists. The proportion of POLSTs completed by hospitalists gradually increased from 2.53% in 2018 to 4.58% in 2019 and 15.9% in 2020. A total of 144 (82.3%) patients had malignancies, while 31 (17.7%) patients had non-cancer illnesses. In 47.4% of the patients, outpatient physicians were involved in completing physician's orders for LST. When the outpatient physicians were involved, more patients signed the POLST form themselves (P=0.02) and chose comfort measures only when asked to determine their preferred LST type (P=0.00). CONCLUSIONS: The completion of POLST by hospitalists is gradually increasing. LST was reduced when the outpatient physicians participated in the completion of POLST. Using measures to increase the involvement of outpatient providers in goal care discussions, the quality and goal concordance of EOL care can be improved.

Effect of the Concomitant Use of Subcutaneous Basal Insulin and Intravenous Insulin Infusion in the Treatment of Severe Hyperglycemic Patients.

BACKGRUOUND: No consensus exists regarding the early use of subcutaneous (SC) basal insulin facilitating the transition from continuous intravenous insulin infusion (CIII) to multiple SC insulin injections in patients with severe hyperglycemia other than diabetic ketoacidosis. This study evaluated the effect of early co-administration of SC basal insulin with CIII on glucose control in patients with severe hyperglycemia. METHODS: Patients who received CIII for the management of severe hyperglycemia were divided into two groups: the early basal insulin group (n=86) if they received the first SC basal insulin 0.25 U/kg body weight within 24 hours of CIII initiation and ≥4 hours before discontinuation, and the delayed basal insulin group (n=79) if they were not classified as the early basal insulin group. Rebound hyperglycemia was defined as blood glucose level of >250 mg/dL in 24 hours following CIII discontinuation. Propensity score matching (PSM) methods were additionally employed for adjusting the confounding factors (n=108). RESULTS: The rebound hyperglycemia incidence was significantly lower in the early basal insulin group than in the delayed basal insulin group (54.7% vs. 86.1%), despite using PSM methods (51.9%, 85.2%). The length of hospital stay was shorter in the early basal insulin group than in the delayed basal insulin group (8.5 days vs. 9.6 days, P=0.027). The hypoglycemia incidence did not differ between the groups. CONCLUSION: Early co-administration of basal insulin with CIII prevents rebound hyperglycemia and shorten hospital stay without increasing the hypoglycemic events in patients with severe hyperglycemia.

Purification of Therapeutic Antibodies Using the Ca2+-Dependent Phase-Transition Properties of Calsequestrin.

Affinity chromatography utilizing specific interactions between therapeutic proteins and bead-immobilized capturing agents is a standard method for protein purification, but its scalability is limited by long purification times, activity loss by the capturing molecules and/or purified protein, and high costs. Here, we report a platform for purifying therapeutic antibodies via affinity precipitation using the endogenous calcium ion-binding protein, calsequestrin (CSQ), which undergoes a calcium ion-dependent phase transition. In this method, ZZ-CSQ fusion proteins with CSQ and an affinity protein (Z domain of protein A) capture antibodies and undergo multimerization and subsequent aggregation in response to calcium ions, enabling the antibody to be collected by affinity precipitation. After robustly validating and optimizing the performance of the platform, the ZZ-CSQ platform can rapidly purify therapeutic antibodies from industrial harvest feedstock with high purity (>97%) and recovery yield (95% ± 3%). In addition, the ZZ-CSQ platform outperforms protein A-based affinity chromatography (PAC) in removing impurities, yielding ∼20-fold less DNA and ∼4.8-fold less host cell protein (HCP) contamination. Taken together, this platform is rapid, recyclable, scalable, and cost-effective, and it shows antibody-purification performance superior or comparable to that of the standard affinity chromatography method.

Immediate intravenous iron administration improves anaemia recovery following total knee arthroplasty: A propensity-matched analysis.

BACKGROUND AND OBJECTIVES: Patients who undergo total knee arthroplasty (TKA) have a risk of postoperative anaemia. This observational study evaluated whether single-dose intravenous ferric carboxymaltose (FCM) administered immediately after TKA facilitates the correction of anaemia. MATERIALS AND METHODS: We retrospectively analysed 722 patients who underwent primary TKA. The FCM group receiving 1000 mg intravenous FCM within one postoperative hour was compared with the non-FCM group that did not receive the medication. A propensity score matching with multiple logistic regression analysis was used to minimize intergroup differences in the baseline characteristics and postoperative blood loss. The rate and severity of postoperative anaemia were compared between the groups, along with haemoglobin (Hb) value, transfusion rate and complications. RESULTS: After propensity score matching, 231 patients were included in each group. In the FCM group, the rate of anaemia at postoperative day (POD) 7 (p = 0.021) and postoperative week (POW) 5 (p < 0.001) and the transfusion rate were significantly lower (p = 0.008). The rate of moderate to severe anaemia at POW-5 was also significantly lower in the FCM group (p < 0.001). In patients without preoperative anaemia (n = 322), the transfusion rate and rate and severity of anaemia at POD-7 and POW-5 were significantly lower in the FCM group than in the non-FCM group. CONCLUSION: Postoperative intravenous FCM administration facilitated recovery of surgery-related anaemia by improving Hb and may reduce the need for transfusion in TKA patients. Preoperative non-anaemic patients could also benefit from accelerated recovery by intravenous iron treatment.

Short-term high-dose intravenous iron reduced peri-operative transfusion after staggered bilateral total knee arthroplasty: A retrospective cohort study.

BACKGROUND AND OBJECTIVES: Staggered bilateral total knee arthroplasty, two procedures performed 4-7 days apart during a single hospitalization, has an increased risk of blood transfusion. This observational study aimed to evaluate whether immediate post-operative single, high-dose intravenous iron supplementation could reduce transfusion requirements and facilitate anaemia recovery in patients. MATERIALS AND METHODS: We retrospectively analysed 131 patients who underwent staggered bilateral total knee arthroplasty. The ferric carboxymaltose (FCM) group received 1000 mg of FCM after the first operation. The non-FCM group did not receive intravenous iron. The transfusion rate and post-operative complications were compared between the groups. The anaemia rate was evaluated pre-operatively, during hospitalization, and 5 weeks after the second total knee arthroplasty. RESULTS: The FCM group comprised 78 patients (59.5%). The rate (21.8% vs. 47.2%, p = 0.004) and amount of transfusion (0 [0-2] vs. 0 [0-0], p = 0.001) was significantly lower in the FCM group than in the non-FCM group. Although both groups' pre-operative haemoglobin concentrations were not significantly different, the FCM group demonstrated higher haemoglobin values 5 weeks post surgery (12.25 ± 0.83 mg/dl vs. 11.48 ± 1.36 mg/dl, p < 0.001). More non-FCM patients developed moderate to severe anaemia at 5 weeks post surgery (p < 0.001). The mortality and complication rates were not significantly different. CONCLUSIONS: Immediate post-operative, high-dose, intravenous iron treatment may contribute to reduced transfusion rates, facilitate haemoglobin recovery after staggered bilateral total knee arthroplasty, and minimize the development of moderate to severe anaemia.

Association of Hepatic Steatosis Index with Nonalcoholic Fatty Liver Disease Diagnosed by Non-Enhanced CT in a Screening Population.

The noninvasive diagnosis of hepatic steatosis is of increasing concern. This study investigated the association of hepatic steatosis determined by non-enhanced CT criteria with clinical parameters in a screening population. Asymptomatic patients who underwent abdominal CT at our healthcare center were retrospectively analyzed (n = 339). Two radiologists measured the attenuation values of the liver parenchyma and spleen using non-enhanced CT images. CT criteria for hepatic steatosis were (a) absolute liver attenuation value <48 Hounsfield units (HU), (b) liver-to-spleen attenuation ratio <0.8, and (c) attenuation difference between the liver and spleen <-10. Body mass index (BMI) and hepatic steatosis index (HSI) were calculated, and laboratory findings were recorded. The association of hepatic steatosis with clinical parameters was assessed using univariate and logistic regression analyses. The presence of hepatic steatosis was significantly associated with the levels of serum fasting glucose and triglycerides, the alanine aminotransferase to aspartate aminotransferase (ALT/AST) ratio, BMI, and HSI values using any of the CT criteria. Logistic regression analysis revealed that the serum fasting glucose level and HSI were significantly associated with hepatic steatosis using criterion (a), while the ALT/AST ratio and HSI were associated with hepatic steatosis using criteria (b) and (c). The presence of hepatic steatosis on non-enhanced CT should be considered to indicate possible clinical profile abnormalities regarding metabolic syndrome.

Management of massive hemorrhage in pregnant women with placenta previa.

Patients with placenta previa are at risk for intra- and postpartum massive blood loss as well as increased risk of placenta accreta, a type of abnormal placental implantation. This condition can lead to serious obstetric complications, including maternal mortality and morbidity. The risk factors for previa include prior cesarean section, multiparity, advanced maternal age, prior placenta previa history, prior uterine surgery, and smoking. The prevalence of previa parturients has increased due to the rising rates of cesarean section and advanced maternal age. For these reasons, we need to identify the risk factors for previa and identify adequate management strategies to respond to blood loss during surgery. This review evaluated the diagnosis of placenta previa and placenta accreta and assessed the risk factors for previa-associated bleeding prior to cesarean section. We then presented intraoperative anesthetic management and other interventions to control bleeding in patients with previa expected to experience massive hemorrhage and require transfusion.

Optimization of the Operating Room Scheduling Process for Improving Efficiency in a Tertiary Hospital.

Efficient operating room (OR) scheduling can improve OR utilization and reduce costs. We hypothesize that the scheduling office (ORSO) leading the modification scheduling process could increase OR utilization rate. Using retrospective data from a single tertiary hospital in two consecutive calendar years, we compared OR utilization rate, the number of daily cases and cumulative operative time in the pre- and post-implementation of scheduling process alteration. We operated about 100,609 cases in the OR during the study period. Daytime utilization rate increased from 85.6% to 89.4% (P < 0.001); overall OR utilization rate from 115.1% to 117.6% (P = 0.019); daily case numbers from 229.9 ± 7.3 to 239.6 ± 7.6 (P = 0.0.14); and cumulative operation time of total and daytime cases from 611.7 case-hour/day to 624.5 case-hour/day (P = 0.013) and from 510.8 case-hour/day to 533.8 case-hour/day (P < 0.001), respectively. Evening/night time case-hour significantly decreased from 100.9 case-hour/day to 90.7 case-hour/day (P < 0.001). The optimization of the scheduling process and coordination by the office during regular workhours resulted in enhanced OR efficiency. The OR scheduling office can act as a control tower to make OR management more flexible, which can improve efficiency and carry financial benefits in tertiary hospitals.

Selection and identification of a novel bone-targeting peptide for biomedical imaging of bone.

The global burden of bone-related diseases is increasing in the aging society; thus, improved bone targeted imaging for their early identification and treatment are needed. In this study, we screened novel peptide ligands for hydroxyapatite, a major inorganic component of teeth and bones, and identified a peptide enabling in vivo bone targeting and real-time fluorescence bone detection. To isolate peptides highly specific for hydroxyapatite, we used negative and positive selection from a randomized 8-mer peptide phage library and identified hydroxyapatite-specific peptides (HA-pep2, HA-pep3, and HA-pep7). Among these three peptides, HA-pep3 showed the highest binding capacity and superior dissociation constant towards hydroxyapatite surfaces over time (~ 88.3% retained on hydroxyapatite after two weeks). Furthermore, HA-pep3 was highly specific for hydroxyapatite compared to other calcium salt-based materials. Using this superior specificity, HA-pep3 showed higher accumulation in skull, spine, and joints in comparison with scrambled control peptide during real-time whole-body imaging. Ex vivo analysis of the major organs and bone from mice demonstrated that the fluorescence intensity in bone was about 3.32 folds higher in the case of HA-pep3 than the one exhibited by the scrambled control peptide. Our study identified a novel approach for targeting ligands for bone specific imaging and can be useful for drug delivery applications.

Comparison of electroencephalogram between propofol- and thiopental-induced anesthesia for awareness risk in pregnant women.

There have been few comparative studies using electroencephalogram (EEG) spectral characteristics during the induction of general anesthesia for cesarean section. This retrospective study investigated the differences in the depth of anesthesia through EEG analysis between propofol- and thiopental-induced anesthesia. We reviewed data of 42 patients undergoing cesarean section who received either thiopental (5 mg/kg) or propofol (2 mg/kg). EEG data were extracted from the bispectral index (BIS) monitor, and 10-second segments were selected from the following sections: 1) Stage I, BIS below 60 after induction; 2) Stage II, after intubation completion; 3) Stage III, end-tidal sevoflurane above 0 vol%. The risk of awareness was represented by the BIS and entropy measures. In Stage III, the thiopental group (n = 20) showed significantly higher BIS value than the propofol group (n = 22) (67.9 [18.66] vs 44.5 [20.63], respectively, p = 0.002). The thiopental group had decreased slow-delta oscillations and increased beta-oscillations as compared to the propofol group in Stages II and III (p < 0.05). BIS, spectral entropy, and Renyi permutation entropy were also higher in the thiopental group at Stages II and III (p < 0.05). In conclusion, frontal spectral EEG analysis demonstrated that propofol induction maintained a deeper anesthesia than thiopental in pregnant women.

Novel fluorescein polymer-based nanoparticles: facile and controllable one-pot synthesis, assembly, and immobilization of biomolecules for application in a highly sensitive biosensor.

A key aspect of biochip and biosensor preparation is optimization of the optical or electrochemical techniques that combine high sensitivity and specificity. Among them, optical techniques such as the use of fluorescent polymeric nanoparticles have resulted in dramatic progress in the field of diagnostics due to their range of advantages. We herein report a facile approach for the development of novel fluorescein polymeric nanoparticles (FPNPs) with immobilization of specific biomolecules for application in a highly sensitive optical biosensor. A series of three amphiphilic fluorescein polymers (poly(FMA-r-NAS-r-MA)), comprising hydrophobic fluorescein O-methacrylate (FMA), hydrophilic N-acryloxysuccinimide (NAS), and methacrylic acid (MA) monomers were synthesized through radical polymerization. In an aqueous environment, these fluorescein polymers self-assembled into spherical shaped nanoparticles with a well-defined particle size, narrow particle size distribution, and enhanced fluorescence properties. The bio-immobilization properties of the FPNPs were also tunable by control of the activated N-hydroxysuccinimide ester group in the polymer series. Furthermore, the fluorescence sensitivity of bovine serum albumin detection by the FPNPs indicates that the limit of detection and sensitivity were improved compared to conventional fluorescence dye-labelled proteins. These novel FPNPs therefore represent a suitable technology for disease diagnosis and biomarker detection to ultimately improve the sensitivity of existing analytical methodologies in a facile and cost-effective manner.