The clinical effectiveness of simulation based airway management education using the Korean emergency airway registry

Introduction. Simulation training with an integrated simulator is appropriate for achieving educational goals in airway management. Thus, we designed this study to evaluate the effectiveness of a simulation based emergency airway management program (SBEAMP) in actual practice. Method. This is a retrospective sub-group analysis of the Korean Emergency Airway Management Registry from 2006 to 2010. We categorized all hospitals into two groups. Six hospitals that actively attended SBEAMP were defined as the ‘participant group’, and the others as the ‘non-participant group’. The types of medicines administered, the use of pre-oxygenation, and the rate of first pass success were compared. Result. The ratio of patients with no medicine received during intubation showed a decrease in both groups but was more rapid in the participant group (p<0.001). The ratio of intubation with sedatives alone was high in the non-participant group (P<0.001). The ratio of intubation with paralytics alone was high in the non-participant group (p<0.001). In the participant group, a combination of both agents was used more frequently (P<0.001). Cases of intubation with both agents and preoxygenation were more prevalent in the participant group (P<0.001). Conclusion. We concluded in this study that SBEAMP had a positive influence on actual clinical outcomes in emergency airway management

Dynamic Pricing with Point Redemption

Many sellers allow consumers to pay with reward points instead of cash or credit card. While the revenue implications of cash purchases are transparent, the implication of reward sales is not trivial, when a firm that issues points is not a seller. In this case, a seller receives a compensation from the point issuer when a consumer purchases the good with points. We examine how reward sales influence a seller's pricing and inventory decisions. We consider a consumer who can choose to pay with cash or points based on reservation price, point balance, and the perceived value of a point. Then, we incorporate this into a pricing model where a seller earns revenues from both cash and reward sales. In contrast to an intuition that reward sales will increase sales and revenue, we show that the effect of reward sales on the seller's price is non-trivial as the seller could either add a premium or discount depending on the inventory level, time, and the reimbursement rate. Furthermore, such price adjustments can attenuate the optimal mark-up or mark-down level, and reduce the price fluctuation caused by inventory level and remaining time. We investigate settings where the seller has different operational controls over reward sales and find that allowing reward sales is still better even when the revenue from the reward sales is smaller than the cash sales. We also find that a seller with an ability to control availability (i.e., allow a reward sale or not) can achieve a revenue similar to the revenue of a seller with an ability to change point requirements and price.https://deepblue.lib.umich.edu/bitstream/2027.42/142796/1/1377_Ahn.pd

On (Re-Scaled) Multi-Attempt Approximation of Customer Choice Model and its Application to Assortment Optimization

Motivated by the classic exogenous demand model and the recently developed Markov chain model, we propose a new approximation to the general customer choice model based on random utility called multi-attempt model, in which a customer may consider several substitutes before finally deciding to not purchase anything. We show that the approximation error of multi-attempt model decreases exponentially in the number of attempts. However, despite its strong theoretical performance, the empirical performance of multi-attempt model is not satisfactory. This motivates us to construct a modification of multi-attempt model called re-scaled multi-attempt model. We show that re-scaled 2-attempt model is exact when the underlying true choice model is Multinomial Logit (MNL); if, however, the underlying true choice model is not MNL, we show numerically that the approximation quality of re-scaled 2-attempt model is very close to that of Markov chain model. The key feature of our proposed approach is that the resulting approximate choice probability can be explicitly written. From a practical perspective, this allows the decision maker to use off-the-shelf solvers, or borrow existing algorithms from literature, to solve a general assortment optimization problem with a variety of real-world constraints.http://deepblue.lib.umich.edu/bitstream/2027.42/122455/1/1322_Ahn.pd

Rapid Detection Strategies for the Global Threat of Zika Virus: Current State, New Hypotheses, and Limitations

The current scenario regarding the widespread Zika virus (ZIKV) has resulted in numerous diagnostic studies, specifically in South America and in locations where there is frequent entry of travelers returning from ZIKV-affected areas, including pregnant women with or without clinical symptoms of ZIKV infection. The World Health Organization, WHO, announced that millions of cases of ZIKV are likely to occur in the United States of America in the near future. This situation has created an alarming public health emergency of international concern requiring the detection of this life-threatening viral candidate due to increased cases of newborn microcephaly associated with ZIKV infection. Hence, this review reports possible methods and strategies for the fast and reliable detection of ZIKV with particular emphasis on current updates, knowledge and new hypotheses that might be helpful for medical professionals in poor and developing countries that urgently need to address this problem. In particular, we emphasize liposome-based biosensors. Although these biosensors are currently among the less popular tools for human disease detection, they have become useful tools for the screening and detection of pathogenic bacteria, fungi and viruses because of their versatile advantageous features compared to other sensing devices. This review summarizes the currently available methods employed for the rapid detection of ZIKV and suggests an innovative approach involving the application of a liposome-based hypothesis for the development of new strategies for ZIKV detection and their use as effective biomedicinal tools

Sonographic measurements of normal gallbladder sizes in children.

PurposeOur goal was to establish the range of sonographic measurements of normal gallbladders in children.MethodsSix hundred ten children aged 0-16 years (male:female ratio, 1.5:1) with normal clinical and laboratory findings were included in this study. The sonographic parameters were the length, width, and calculated volume of the gallbladder, and the clinical parameters were the age, height, weight, and body surface area of the children. Statistical significance was determined through correlation and regression analyses.ResultsThe length of the gallbladder showed significant positive correlations with age (r = 0.65), height (r = 0.67), weight (r = 0.63), and body surface area (r = 0.65; p &lt; 0.01). The calculated volume of the gallbladder also showed moderate correlations with age (r = 0.53), height (r = 0.55), weight (r = 0.61), and body surface area (r = 0.57; p &lt; 0.01). The gallbladder width showed modest but significant correlations with age (r = 0.48), height (r = 0.53), weight (r = 0.53), and body surface area (r = 0.55; p &lt; 0.01). The highest correlation coefficients were found between the gallbladder length and subject age (r = 0.65; p &lt; 0.01) and between the gallbladder length and subject height (r = 0.67; p &lt; 0.01). For all correlations, statistical significance remained after regression analysis (p &lt; 0.01).ConclusionsValues for the size of the normal pediatric gallbladder are defined and will be helpful in the diagnosis of gallbladder abnormalities

Studying cancer immunotherapy using patient-derived xenografts (PDXs) in humanized mice.

Cancer immunotherapy is a promising way to eliminate tumor cells by using the patient\u27s own immune system. Selecting the appropriate animal models to develop or validate preclinical immunotherapeutic trials is now an important aspect of many cancer research programs. Here we discuss the advantages and limitations of using genetically engineered immunodeficient mouse models, patient-derived xenografts (PDXs), and humanized mouse models for developing and testing immunotherapeutic strategies

Persistent Pemphigus Vulgaris Showing Features of Tufted Hair Folliculitis

Pemphigus vulgaris is an autoimmune blistering disease that commonly involves the scalp. Lesions of pemphigus vulgaris that persist on the scalp for a long period may be accompanied by tufted hair folliculitis. Only two previous accounts of tufted hair folliculitis developing in a lesion of pemphigus vulgaris have been reported. We report a 51-year-old-man with erosions and clusters of hair on the scalp. The scalp lesion had persisted for about 20 years. A histopathological examination of the skin lesion on the scalp revealed separation of the epidermis and clusters of several adjacent hair follicles. The patient was diagnosed with persistent pemphigus vulgaris of the scalp showing features of tufted hair folliculitis

Recurred pneumocephalus in a head trauma patient following positive pressure mask ventilation during induction of anesthesia -A case report-

Pneumocephalus is a condition which usually results from head trauma. It has been known that iatrogenic pneumocephalus can occur as a complication of positive pressure mask ventilation during induction of anesthesia or ventilatory care for head trauma patients. We report a case of mask ventilation during anesthesia induction in a 50-year-old male patient with head trauma. Initial pneumocephalus associated with cerebrospinal fluid leakage was diagnosed immediate following head injury involving facial sinuses. He was managed with emergent lumbar drainage and supportive care. Pneumocephalus recurred following positive pressure mask ventilation (PPMV) during anesthesia induction for surgery on the right arm. Recurred pneumocephalus was managed with high flow oxygen and supportive care. Anesthesiologists should be aware of pneumocephalus as a potential complication of PPMV in head trauma patients, even after resolution of previous pneumocephalus

Human AP endonuclease suppresses DNA mismatch repair activity leading to microsatellite instability

The multifunctional mammalian apurinic/apyrimidinic (AP) endonuclease (APE) participates in the repair of AP sites in the cellular DNA as well as participating in the redox regulation of the transcription factor function. The function of APE is considered as the rate-limiting step in DNA base excision repair. Paradoxically, an unbalanced increase in APE protein leads to genetic instability. Therefore, we investigated the mechanisms of genetic instability that are induced by APE. Here, we report that the overexpression of APE protein disrupts the repair of DNA mismatches, which results in microsatellite instability (MSI). We found that expression of APE protein led to the suppression of the repair of DNA mismatches in the normal human fibroblast cells. Western blot analysis revealed that hMSH6 protein was markedly reduced in the APE-expressing cells. Moreover, the addition of purified Mutα (MSH2 and MSH6 complex) to the extracts from the APE-expressing cells led to the restoration of mismatch repair (MMR) activity. By performing MMR activity assay and MSI analysis, we found that the co-expression of hMSH6 and APE exhibited the microsatellite stability, whereas the expression of APE alone generated the MSI-high phenotype. The APE-mediated decrease in MMR activity described here demonstrates the presence of a new and highly effective APE-mediated mechanism for MSI