Impact of COVID-19 pandemic on interhospital transfer of patients with major trauma in Korea: a retrospective cohort study

BACKGROUND

Interhospital transfer (IHT) is necessary for providing ultimate care in the current emergency care system, particularly for patients with severe trauma. However, studies on IHT during the pandemic were limited. Furthermore, evidence on the effects of the coronavirus disease 2019 (COVID-19) pandemic on IHT among patients with major trauma was lacking.

METHOD

This retrospective cohort study was conducted in an urban trauma center (TC) of a tertiary academic affiliated hospital in Daegu, Korea. The COVID-19 period was defined as from February 1, 2020 to January 31, 2021, whereas the pre-COVID-19 period was defined as the same duration of preceding span. Clinical data collected in each period were compared. We hypothesized that the COVID-19 pandemic negatively impacted IHT.

RESULTS

A total of 2,100 individual patients were included for analysis. During the pandemic, the total number of IHTs decreased from 1,317 to 783 (- 40.5%). Patients were younger (median age, 63 [45-77] vs. 61[44-74] years, p = 0.038), and occupational injury was significantly higher during the pandemic (11.6% vs. 15.7%, p = 0.025). The trauma team activation (TTA) ratio was higher during the pandemic both on major trauma (57.3% vs. 69.6%, p = 0.006) and the total patient cohort (22.2% vs. 30.5%, p < 0.001). In the COVID-19 period, duration from incidence to the TC was longer (218 [158-480] vs. 263[180-674] minutes, p = 0.021), and secondary transfer was lower (2.5% vs. 0.0%, p = 0.025).

CONCLUSION

We observed that the total number of IHTs to the TC was reduced during the COVID-19 pandemic. Overall, TTA was more frequent, particularly among patients with major trauma. Patients with severe injury experienced longer duration from incident to the TC and lesser secondary transfer from the TC during the COVID-19 pandemic.

Long-term clinical outcomes after high and low ligations with lymph node dissection around the root of the inferior mesenteric artery in patients with rectal cancer

PURPOSE

This study aimed to evaluate the long-term clinical outcomes based on the ligation level of the inferior mesenteric artery (IMA) in patients with rectal cancer.

METHODS

This was a retrospective analysis of a prospectively collected database that included all patients who underwent elective low anterior resection for rectal cancer between January 2013 and December 2019. The clinical outcomes included oncological outcomes, postoperative complications, and functional outcomes. The oncological outcomes included overall survival (OS) and relapse-free survival (RFS). The functional outcomes, including defecatory and urogenital functions, were analyzed using the Fecal Incontinence Severity Index, International Prostate Symptom Score, and International Index of Erectile Function questionnaires.

RESULTS

In total, 545 patients were included in the analysis. Of these, 244 patients underwent high ligation (HL), whereas 301 underwent low ligation (LL). The tumor size was larger in the HL group than in the LL group. The number of harvested lymph nodes (LNs) was higher in the HL group than in the LL group. There were no significant differences in complication rates and recurrence patterns between the groups. There were no significant differences in 5-year RFS and OS between the groups. Cox regression analysis revealed that the ligation level (HL vs. LL) was not a significant risk factor for oncological outcomes. Regarding functional outcomes, the LL group showed a significant recovery in defecatory function 1 year postoperatively compared with the HL group.

CONCLUSION

LL with LNs dissection around the root of the IMA might not affect the oncologic outcomes comparing to HL; however, it has minimal benefit for defecatory function.

Coronavirus disease pandemic impact on emergency department visits for cardiovascular disease in Korea: A review

The coronavirus disease (COVID-19) pandemic has affected patient visits to the hospital, including visits to the emergency department (ED). This study aimed to analyze the impact of the COVID-19 pandemic on the patterns of ED visits and treatment in hospitals for diseases requiring urgent diagnosis and treatment. We analyzed entries from the South Korea National Emergency Department Information System claims database between January 1, 2018 and December 31, 2020. We analyzed data of patients who visited the ED with acute myocardial infarction (AMI), acute ischemic stroke (AIS), and acute hemorrhagic stroke (AHS). We found that the COVID-19 pandemic had impacted ED utilization and fatality in patients with AMI, AIS, and AHS.

Prehospital factors associated with out-of-hospital cardiac arrest outcomes in a metropolitan city: a 4-year multicenter study

BACKGROUND

Prehospital factors play a vital role in out-of-hospital cardiac arrest (OHCA) survivability, and they vary between countries and regions. We investigated the prehospital factors associated with OHCA outcomes in a single metropolitan city in the Republic of Korea.

METHODS

This study included adult medical OHCA patients enrolled prospectively, using data from the citywide OHCA registry for patients registered between 2018 and 2021. The primary outcome was survival to hospital discharge. Multivariable logistic regression analysis was conducted to determine the factors associated with the study population's clinical outcomes, adjusting for covariates. We performed a sensitivity analysis for clinical outcomes only for patients without prehospital return of spontaneous circulation prior to emergency medical service departure from the scene.

RESULTS

In multivariable logistic regression analysis, older age (odds ratio [OR] 0.96; 95% confidence interval [CI] 0.95-0.97), endotracheal intubation (adjusted odds ratio [aOR] 0.29; 95% [CIs] 0.17-0.51), supraglottic airway (aOR 0.29; 95% CI 0.17-0.51), prehospital mechanical chest compression device use (OR 0.13; 95% CI 0.08-0.18), and longer scene time interval (OR 0.96; 95% CI 0.93-1.00) were negatively associated with survival. Shockable rhythm (OR 24.54; 95% CI 12.99-42.00), pulseless electrical activity (OR 3.11; 95% CI 1.74-5.67), and witnessed cardiac arrest (OR 1.59; 95% CI 1.07-2.38) were positively associated with survival. In the sensitivity analysis, endotracheal intubation, supraglottic airway, prehospital mechanical chest compression device use, and longer scene time intervals were associated with significantly lower survival to hospital discharge.

CONCLUSIONS

Regional resuscitation protocol should be revised based on the results of this study, and modifiable prehospital factors associated with lower survival of OHCA should be improved.

Kikuchi-Fujimoto Disease: A Case of Febrile Cervical Lymphadenopathy With Hematological Abnormalities

Kikuchi-Fujimoto disease (KFD), or histiocytic necrotizing lymphadenitis, is a benign but rare disorder associated with febrile cervical lymphadenopathy in young adults. Here, we discuss a case of a young female patient presenting with left tender cervical lymphadenopathy that progressed bilaterally with a fever of unknown origin. Laboratory parameters showed persistent leukopenia, especially neutropenia, which fluctuated with the degree of symptom severity. Two months were taken to confirm the diagnosis of KFD based on the histological interpretation of the lymph node biopsy. Supportive management with analgesics and paracetamol formed the main treatment. This case highlights the challenges and importance of diagnosing KFD to exclude other serious conditions such as lymphoma, tuberculosis, or lupus lymphadenitis that share similar clinical manifestations as KFD.

Toxoplasmic Lymphadenitis of the Head and Neck Region

OBJECTIVE

We analyzed the clinical characteristics and treatment results in patients with a final diagnosis of toxoplasmic lymphadenitis after surgery.

METHODS

A total of 23 patients with a final diagnosis of toxoplasmic lymphadenitis of the head and neck region after surgery from January 2010 to August 2022 were enrolled.

RESULTS

All patients with toxoplasmic lymphadenitis presented with a neck mass and a mean age of over 40. The most common location of toxoplasma lymphadenitis in the head and neck was neck level II in 9 patients, followed by level I, level V, level III, the parotid gland, and level IV. Three patients had masses in multiple regions of the neck. Preoperative diagnosis (based on imaging tests, physical examination, and fine-needle aspiration cytology results) was benign lymph node enlargement in 11 cases, malignant lymphoma in 8 cases, metastatic carcinoma in 2 cases, and parotid tumors in 2 cases. All patients underwent surgical resection and were diagnosed with toxoplasma lymphadenitis based on the final biopsy. There were no major complications after surgery. A total of 10 patients (43.5%) received additional antibiotics after surgery. There was no recurrence of toxoplasmic lymphadenitis during the follow-up period.

CONCLUSIONS

It is challenging to assess the diagnostic accuracy of preoperative examination in toxoplasma lymphadenitis; hence, surgical resection is necessary to differentiate it from other diseases.

Regional Difference in the Effect of Food Accessibility and Affordability on Vegetable and Fruit Acquisition and Healthy Eating Behaviors for Older Adults

The food environment has been determined to affect a range of healthy eating and health indicators, but the study on the regional difference of food environment effects on these outcomes is limited. This study aimed to examine whether food environment factors influence vegetable and fruit acquisition and healthy eating behaviors in urban and rural areas using a nationwide dataset. The study participants were community-dwelling older adults aged 65 years and older (n = 830) who participated in the 2019 Consumer Behavior Survey for Food provided by the Korea Rural Economic Institute. Food environment factors were assessed using questionnaires measuring perceived food accessibility and affordability. The negative perceptions of food environment were related to lower vegetable and fruit acquisitions and poor healthy eating behaviors. The higher risks of low vegetable and fruit acquisitions in older rural adults were related to a negative perception of food accessibility only (odds ratio [OR]: 2.34, 95% confidence interval [CI]: 1.27-4.32 for vegetable; OR: 1.96, 95% CI: 1.02-3.75 for fruit). For older urban adults, negative perceptions of both food accessibility and food affordability were related to the increased risk of low vegetable acquisition (OR: 2.03, 95% CI: 1.07-3.83 for food accessibility; OR: 2.52, 95% CI: 1.26-5.04 for food affordability). In terms of healthy eating behaviors, for those who perceived that either food accessibility or affordability was poor, older urban adults were less likely to have various and healthy food eating behaviors when they had a negative perception of affordability (OR: 0.47, 95% CI: 0.25-0.90 for variety; OR: 0.23, 95% CI: 0.11-0.46 for eating healthy foods); however, older rural adults were less likely to have the behaviors when they had a negative perception of accessibility (OR: 0.49, 95% CI: 0.21-0.97 for variety; OR: 0.28, 95% CI: 0.13-0.63 for eating healthy foods). In conclusion, the negative perceptions of food accessibility and affordability were related to low vegetable acquisition and poor healthy eating behaviors. The effects of food accessibility and affordability on vegetable and fruit acquisitions and healthy eating behaviors were different between urban and rural areas.

Neurologic outcomes of prehospital mechanical chest compression device use during transportation of out-of-hospital cardiac arrest patients: a multicenter observational study

Objective

High-quality cardiopulmonary resuscitation with chest compression is important for good neurologic outcomes during out-of-hospital cardiac arrest (OHCA). Several types of mechanical chest compression devices have recently been implemented in Korean emergency medical services. This study aimed to identify the effect of prehospital mechanical chest compression device use on the outcomes of OHCA patients.

Methods

We retrospectively analyzed data drawn from the regional cardiac arrest registry in Daegu, Korea. This registry prospectively collected data from January 2017 to December 2020. Patients aged 18 years or older who experienced cardiac arrest presumed to have a medical etiology were included. The exposure variable was the use of a prehospital mechanical device during transportation by emergency medical technicians. The outcomes measured were neurologic outcomes and survival to discharge. Logistic regression analysis was used.

Results

Among 3,230 OHCA patients, 1,111 (34.4%) and 2,119 (65.6%) were managed with manual chest compression and with a mechanical chest compression device, respectively. The mechanical chest compression group showed poorer neurologic outcomes than the manual chest compression group (adjusted odds ratio, 0.12; 95% confidence interval, 0.04-0.33) and decreased survival to discharge (adjusted odds ratio, 0.39; 95% confidence interval, 0.19-0.82) after adjustment for confounding variables.

Conclusion

Prehospital mechanical chest compression device use in OHCA was associated with poorer neurologic outcomes and survival to discharge compared to manual chest compression.

Exploring the experiences and perspectives of emergency physicians on brain death organ tissue donation after the Life-Sustaining Treatment Decision Act

Background

This study explored emergency physicians’ experiences and perspectives related to brain death organ tissue donation (OTD) after the enforcement of the Life-Sustaining Treatment (LST) Decision Act in Korea.

Methods

Using the Braun and Clarke thematic analysis method, this qualitative study analyzed interview data—comprising experiences and perspectives of brain death OTD since the LST Decision Act—of 10 emergency physicians who specialized in targeted temperature management (TTM) and cared for post-cardiac arrest patients.

Results

Data analysis revealed 13 subthemes and 5 themes the LST Decision Act is easier to explain to family members than brain death OTD, but it does not fit well in an emergency medical setting; many family members decide to stop LST even before physicians mention brain death or OTD; family members view stopping LST as being about comforting patients without bothering them, and decision-makers are therefore no longer willing to choose OTD; stopping LST does not always result in brain death, but cases of brain death are preceded by stopping LST; and since the LST Decision Act, the number of TTM cases and potential brain death donors has decreased.

Conclusions

Unless a supplementary policy that connects stopping LST to brain death OTD is prepared, the withdrawal of LST in patients resuscitated after cardiac arrest is expected to continue, and brain death OTD is expected to decrease.

Analysis of Factors Affecting Emergency Physicians' Attitudes toward Deceased Organ & Tissue Donation

BACKGROUND

This study aimed to investigate differences in knowledge, and attitudes toward deceased organ and tissue donation of emergency physicians. Additionally, we analyzed factors affecting the attitudes toward deceased organ and tissue donation.

METHODS

We conducted a survey of specialists and residents registered with the Korean Society of Emergency Medicine in December 2020. The respondents' sex, age, position, personal registration for organ donation, experience of soliciting organ donation, participation in related education, knowledge, and attitude about brain death organ donation, and attitude toward stopping life-sustaining treatments were investigated. According to the characteristics of the respondents (specialists or residents, experience and education on organ and tissue donation), their knowledge and attitude toward deceased organ donation were compared. Stepwise hierarchical multiple regression analysis was used to investigate the factors affecting the attitudes toward deceased organ and tissue donation.

RESULTS

Of the total 428 respondents, there were 292 emergency medicine specialists and 136 medical residents. Specialists and those who registered or wished to donate organs had higher knowledge and attitude scores regarding deceased organ and tissue donation. Those who had experience recommending organ and tissue donation more than 6 times had higher knowledge scores on deceased organ and tissue donation and higher overall scores in attitude. Those who received education from the Korean Organ Donation Agency had higher knowledge scores. Specialists, and those who wished to donate or had registered as organ donors and had a higher life-sustaining treatment attitude score and knowledge about deceased organ and tissue donation, had more positive attitudes toward deceased organ and tissue donation.

CONCLUSION

For more potential deceased organ and tissue donors to be referred for donation, there should be continuous education for emergency physicians on brain-dead organ and tissue donation-related knowledge and procedures. In addition, institutional or systematic improvements that can lead to organ donation when deciding on the withdrawal of life-sustaining treatment should be considered.

Optimal Definition of Biochemical Recurrence in Patients Who Receive Salvage Radiotherapy Following Radical Prostatectomy for Prostate Cancer

Purpose

This study proposed the optimal definition of biochemical recurrence (BCR) after salvage radiotherapy (SRT) following radical prostatectomy for prostate cancer.

Materials and Methods

Among 1,117 patients who had received SRT, data from 205 hormone-naïve patients who experienced post-SRT prostate-specific antigen (PSA) elevation were included in a multi-institutional database. The primary endpoint was to determine the PSA parameters predictive of distant metastasis (DM). Absolute serum PSA levels and the prostate-specific antigen doubling time (PSA-DT) were adopted as PSA parameters.

Results

When BCR was defined based on serum PSA levels ranging from 0.4 ng/mL to nadir+2.0 ng/mL, the 5-year probability of DM was 27.6%–33.7%. The difference in the 5-year probability of DM became significant when BCR was defined as a serum PSA level of 0.8 ng/ml or higher (1.0–2.0 ng/mL). Application of a serum PSA level of ≥ 0.8 ng/mL yielded a c-index value of 0.589. When BCR was defined based on the PSA-DT, the 5-year probability was 22.7%–39.4%. The difference was significant when BCR was defined as a PSA-DT ≤ 3 months and ≤ 6 months. Application of a PSA-DT ≤ 6 months yielded the highest c-index (0.660). These two parameters complemented each other; for patients meeting both PSA parameters, the probability of DM was 39.5%–44.5%; for those not meeting either parameter, the probability was 0.0%–3.1%.

Conclusion

A serum PSA level > 0.8 ng/mL was a reasonable threshold for the definition of BCR after SRT. In addition, a PSA-DT ≤ 6 months was significantly predictive of subsequent DM, and combined application of both parameters enhanced predictability.

Impact of an emergency department resident strike during the coronavirus disease 2019 (COVID-19) pandemic in Daegu, South Korea

Background

To prepare for future work stoppages in the medical industry, this study aimed to identify the effects of healthcare worker strikes on the mortality rate of patients visiting the emergency department (ED) at six training hospitals in Daegu, Korea.

Methods

We used a retrospective, cross-sectional, multicenter design to analyze the medical records of patients who visited six training hospitals in Daegu (August 21-September 8, 2020). For comparison, control period 1 was set as the same period in the previous year (August 21-September 8, 2019) and control period 2 was set as July 1-19, 2020. Patient characteristics including age, sex, and time of ED visit were investigated along with mode of arrival, length of ED stay, and in-hospital mortality. The experimental and control groups were compared using t-tests, and Mann-Whitney U-test, chi-square test, and Fisher exact tests, as appropriate. Univariate logistic regression was performed to identify significant factors, followed by multivariate logistic regression analysis.

Results

During the study period, 31,357 patients visited the ED, of which 7,749 belonged to the experimental group. Control periods 1 and 2 included 13,100 and 10,243 patients, respectively. No significant in-hospital mortality differences were found between study periods; however, the results showed statistically significant differences in the length of ED stay.

Conclusion

The ED resident strike did not influence the mortality rate of patients who visited the EDs of six training hospitals in Daegu. Furthermore, the number of patients admitted and the length of ED stay decreased during the strike period.

Public awareness and willingness to use automated external defibrillators in a metropolitan city

Objective

Early defibrillation is crucial for the survival of patients with out-of-hospital cardiac arrest. This study aimed to examine the trends and associated factors regarding public awareness and willingness to use automated external defibrillators (AEDs) through citywide surveys.

Methods

Three-round surveys were conducted in February 2012 (n=1,000), December 2016 (n=1,141), and December 2018 (n=1,001) among citizens in Daegu, South Korea, who were aged ≥19 years. The subjects were selected through a three-stage quota sampling. Awareness and willingness to use an AED were assessed in the three groups. The primary outcome was willingness to use AEDs.

Results

Of 3,142 respondents, 3,069 were eligible for analysis. The proportion of respondents who knew how to use AEDs increased from 4.7% in 2012 to 20.8% in 2018. Of the respondents in 2012, 2016, and 2018, 39.7%, 50.0%, and 43.2%, respectively, were willing to use an AED. Factors associated with willingness to use AEDs were male sex (adjusted odds ratio [AOR], 1.39; 95% confidence interval [CI], 1.10–1.75), cardiopulmonary resuscitation training experience in the previous 2 years (AOR, 1.80; 95% CI, 1.43–2.28), recognition of the Good Samaritan law (AOR, 1.45; 95% CI, 1.13–1.86), and awareness of how to use an AED (AOR, 4.40; 95% CI, 3.26–5.93).

Conclusion

To increase willingness to use AEDs, education in AED use and the Good Samaritan law, along with re-education to maintain knowledge of AED use, should be considered.

Clinical usefulness of deep learning-based automated segmentation in intracranial hemorrhage

BACKGROUND

Doctors with various specializations and experience order brain computed tomography (CT) to rule out intracranial hemorrhage (ICH). Advanced artificial intelligence (AI) can discriminate subtypes of ICH with high accuracy.

OBJECTIVE

The purpose of this study was to investigate the clinical usefulness of AI in ICH detection for doctors across a variety of specialties and backgrounds.

METHODS

A total of 5702 patients' brain CTs were used to develop a cascaded deep-learning-based automated segmentation algorithm (CDLA). A total of 38 doctors were recruited for testing and categorized into nine groups. Diagnostic time and accuracy were evaluated for doctors with and without assistance from the CDLA.

RESULTS

The CDLA in the validation set for differential diagnoses among a negative finding and five subtypes of ICH revealed an AUC of 0.966 (95% CI, 0.955-0.977). Specific doctor groups, such as interns, internal medicine, pediatrics, and emergency junior residents, showed significant improvement with assistance from the CDLA (p= 0.029). However, the CDLA did not show a reduction in the mean diagnostic time.

CONCLUSIONS

Even though the CDLA may not reduce diagnostic time for ICH detection, unlike our expectation, it can play a role in improving diagnostic accuracy in specific doctor groups.

Gender differences in the effect of depression and cognitive impairment on risk of falls among community-dwelling older adults

BACKGROUND

The impact of the interrelationship between depression and cognitive impairment on risk of falls remains unclear. In addition, gender differences should be considered to further understand the relationships between depression, cognitive impairment, and risk of falls.

METHODS

Older adults who completed the Living Profiles of Older People Survey in Korea were included. In total, 14,055 participants completed the baseline survey, and 7,150 participants completed a follow-up survey after 3 years. We classified participants into 4 groups based on depression and cognitive impairment.

RESULTS

Using generalized estimating equation models, older adults with depression but without cognitive impairment had a higher risk of falls (OR=1.49, 95% CI=1.35-1.63), compared to a reference group with neither depression nor cognitive impairment. However, older adults who had cognitive impairment but not depression had a similar risk of falls (OR=1.03, 95% CI=0.91-1.16) to the reference group. Finally, older adults who had both depression and cognitive impairment had the highest risk of falls (OR=1.95, 95% CI=1.73-2.20) compared to the reference group. In addition, depression seemed to have a bigger effect on the risk of falls in men compared to women (p for interaction < 0.001).

LIMITATIONS

These results should be interpreted with caution, considering the use of screening tool for defining depression or cognitive impairment, and lack of information on psychotropic medication use.

CONCLUSIONS

Depression alone or depression combined with cognitive impairment was associated with higher risk of falls in older adults. In addition, gender differences in the risk of falls was noted.

Sociability increases survival of adult female giraffes

Studies increasingly show that social connectedness plays a key role in determining survival, in addition to natural and anthropogenic environmental factors. Few studies, however, integrated social, non-social and demographic data to elucidate what components of an animal's socio-ecological environment are most important to their survival. Female giraffes (Giraffa camelopardalis) form structured societies with highly dynamic group membership but stable long-term associations. We examined the relative contributions of sociability (relationship strength, gregariousness and betweenness), together with those of the natural (food sources and vegetation types) and anthropogenic environment (distance from human settlements), to adult female giraffe survival. We tested predictions about the influence of sociability and natural and human factors at two social levels: the individual and the social community. Survival was primarily driven by individual- rather than community-level social factors. Gregariousness (the number of other females each individual was observed with on average) was most important in explaining variation in female adult survival, more than other social traits and any natural or anthropogenic environmental factors. For adult female giraffes, grouping with more other females, even as group membership frequently changes, is correlated with better survival, and this sociability appears to be more important than several attributes of their non-social environment.

Epidemiology and risk factors for sports- and recreation-related eye injury: a multicenter prospective observational study

AIM

To identify the epidemiologic characteristics of sports- and recreation-related eye injuries in a large metropolitan city and investigate risk factors associated with visual impairment.

METHODS

We performed a multicenter prospective observational study on patients using the regional eye injury registry data. This study included patients with sports- and recreation-related eye injury in four tertiary teaching hospitals in Daegu, Republic of Korea, from August 2016 to July 2018. The primary outcome was visual impairment at the first hospital visit. Distributions of sex, age, place, and causative materials were analyzed according to causative activities. To examine the association between causative activities and visual impairment, a Logistic regression analysis was used.

RESULTS

Of the 349 sports- and recreation-related eye injuries, soccer was the most common causative activity, with 21.8% (n=76). Sports- and recreation-related eye injuries occurred mainly in teenagers, individuals in their 20s, and men. Badminton and soccer were significantly associated with visual impairment at the first hospital visit compared with combat sports [(adjusted odds ratio (AOR), 5.18; 95% confidence interval (CI), 1.67-16.09 for badminton and AOR, 3.87; 95%CI, 1.36-10.99 for soccer].

CONCLUSION

Intervention efforts such as deployment of protective eyewear in sports facilities and schools and promotion of wearing protective eyewear during these activities in teenagers and individuals in their 20s are mandatory.

Development of an Automated Image Analyzer for Microvessel Density Measurement in Bone Marrow Biopsies

Angiogenesis is important for the proliferation and survival of multiple myeloma (MM) cells. Bone marrow (BM) microvessel density (MVD) is a useful marker of angiogenesis and an increase in MVD can be used as a marker of poor prognosis in MM patients. We developed an automated image analyzer to assess MVD from images of BM biopsies stained with anti-CD34 antibodies using two color models. MVD was calculated by merging images from the red and hue channels after eliminating non-microvessels. The analyzer results were compared with those obtained by two experienced hematopathologists in a blinded manner using the 84 BM samples of MM patients. Manual assessment of the MVD by two hematopathologists yielded mean±SD values of 19.4±11.8 and 20.0±11.8. The analyzer generated a mean±SD of 19.5±11.2. The intraclass correlation coefficient (ICC) and Bland-Altman plot of the MVD results demonstrated very good agreement between the automated image analyzer and both hematopathologists (ICC=0.893 [0.840–0.929] and ICC=0.906 [0.859–0.938]). This automated analyzer can provide time- and labor-saving benefits with more objective results in hematology laboratories.

Deep-learning algorithms for the interpretation of chest radiographs to aid in the triage of COVID-19 patients: A multicenter retrospective study

The recent medical applications of deep-learning (DL) algorithms have demonstrated their clinical efficacy in improving speed and accuracy of image interpretation. If the DL algorithm achieves a performance equivalent to that achieved by physicians in chest radiography (CR) diagnoses with Coronavirus disease 2019 (COVID-19) pneumonia, the automatic interpretation of the CR with DL algorithms can significantly reduce the burden on clinicians and radiologists in sudden surges of suspected COVID-19 patients. The aim of this study was to evaluate the efficacy of the DL algorithm for detecting COVID-19 pneumonia on CR compared with formal radiology reports. This is a retrospective study of adult patients that were diagnosed as positive COVID-19 cases based on the reverse transcription polymerase chain reaction among all the patients who were admitted to five emergency departments and one community treatment center in Korea from February 18, 2020 to May 1, 2020. The CR images were evaluated with a publicly available DL algorithm. For reference, CR images without chest computed tomography (CT) scans classified as positive for COVID-19 pneumonia were used given that the radiologist identified ground-glass opacity, consolidation, or other infiltration in retrospectively reviewed CR images. Patients with evidence of pneumonia on chest CT scans were also classified as COVID-19 pneumonia positive outcomes. The overall sensitivity and specificity of the DL algorithm for detecting COVID-19 pneumonia on CR were 95.6%, and 88.7%, respectively. The area under the curve value of the DL algorithm for the detection of COVID-19 with pneumonia was 0.921. The DL algorithm demonstrated a satisfactory diagnostic performance comparable with that of formal radiology reports in the CR-based diagnosis of pneumonia in COVID-19 patients. The DL algorithm may offer fast and reliable examinations that can facilitate patient screening and isolation decisions, which can reduce the medical staff workload during COVID-19 pandemic situations.

QRS complex characteristics and patient outcomes in out-of-hospital pulseless electrical activity cardiac arrest

BACKGROUND

Pulseless electrical activity (PEA) is increasingly observed in out-of-hospital cardiac arrest (OHCA), but outcomes are still poor. We aimed to assess the relationship between QRS characteristics and outcomes of patients with OHCA with initial PEA (OHCA-P).

METHODS

This prospective observational study included patients aged at least 18 years who developed OHCA-P between 1 January 2016 and 31 December 2018, and were enrolled in the Daegu Emergency Medical Services registry, South Korea. We performed multivariable logistic regression analyses to identify the associations between QRS characteristics and OHCA-P outcomes, in which QRS complexes were considered separately (model 1) and simultaneously (model 2). The primary outcome was survival to hospital discharge and the secondary outcome was a favourable neurological outcome.

RESULTS

Of the 3659 patients with OHCA, 576 were enrolled (median age 73 years; 334 men). A higher QRS amplitude was associated with survival to hospital discharge and a favourable neurological outcome in model 1 (adjusted OR (aOR) 1.077 and 1.106, respectively; 95% CI 1.021 to 0.136 and 1.029 to 1.190, respectively) and model 2 (aOR 1.084 and 1.123, respectively; 95% CI 1.026 to 1.145 and 1.036 to 1.216, respectively). A QRS width of <120 ms was associated with survival to hospital discharge and a favourable neurological outcome in model 1 (aOR 3.371 and 4.634, respectively; 95% CI 1.633 to 6.960 and 1.562 to 13.144, respectively) and model 2 (aOR 3.213 and 5.103, respectively; 95% CI 1.568 to 6.584 and 1.682 to 15.482, respectively). Survival to hospital discharge and neurological outcome were not associated with QRS frequency.

CONCLUSION

OHCA-P outcomes were better when the initial QRS complex showed a higher amplitude or narrower width.

Long-term benefits of chest compression-only cardiopulmonary resuscitation training using real-time visual feedback manikins: a randomized simulation study

Objective

Cardiopulmonary resuscitation (CPR) education with a feedback device is known to result in better CPR skills compared to one without the feedback device. However, its long-term benefits have not been established. The purpose of this study was to evaluate the long-term CPR skill retention after training using real-time visual manikins in comparison to that of non-feedback manikins.

Methods

We recruited 120 general university students who were randomly divided into the real-time feedback group (RTFG) and the non-feedback group. Of them, 95 (RTFG, 48; non-feedback group, 47) attended basic life support and automated external defibrillation training for 1 hour. For comparison of retention of CPR skills, the two groups were evaluated based on 2-minute chest compression performed immediately after training and at 3, 6, and 9 months. The CPR parameters between the two groups were also compared using a generalized linear model.

Results

At immediately after training, the performance of RTFG was better in terms of average chest compression depth (51.9±1.1 vs. 45.5±1.1, p<0.001) and a higher percentage of adequate chest compression depth (51.0±4.1 vs. 26.9±4.2, p<0.001). This significant difference was maintained until 6 months after training, but there was no difference at 9 months after training. However, there was no significant difference in the chest compression rate and the correct hand position at any time point.

Conclusion

CPR training with a real-time visual feedback manikin improved skill acquisition in chest compression depth, but only until 6 months after the training. It could be a more effective educational method for basic life support training in laypersons.

Revised Triage and Surveillance Protocols for Temporary Emergency Department Closures in Tertiary Hospitals as a Response to COVID-19 Crisis in Daegu Metropolitan City

BACKGROUND

When an emergency-care patient is diagnosed with an emerging infectious disease, hospitals in Korea may temporarily close their emergency departments (EDs) to prevent nosocomial transmission. Since February 2020, multiple, consecutive ED closures have occurred due to the coronavirus disease 2019 (COVID-19) crisis in Daegu. However, sudden ED closures are in contravention of laws for the provision of emergency medical care that enable the public to avail prompt, appropriate, and 24-hour emergency medical care. Therefore, this study ascertained the vulnerability of the ED at tertiary hospitals in Daegu with regard to the current standards. A revised triage and surveillance protocol has been proposed to tackle the current crisis.

METHODS

This study was retrospectively conducted at 6 level 1 or 2 EDs in a metropolitan city where ED closure due to COVID-19 occurred from February 18 to March 26, 2020. The present status of ED closure and patient characteristics and findings from chest radiography and laboratory investigations were assessed. Based on the experience from repeated ED closures and the modified systems that are currently used in EDs, revised triage and surveillance protocols have been developed and proposed.

RESULTS

During the study period, 6 level 1 or 2 emergency rooms included in the study were shut down 27 times for 769 hours. Thirty-one confirmed COVID-19 cases, of whom 7 died, were associated with the incidence of ED closure. Typical patient presentation with respiratory symptoms of COVID-19 was seen in less than 50% of patients, whereas abnormal findings on chest imaging investigations were detected in 93.5% of the study population. The chest radiography facility, resuscitation rooms, and triage area were moved to locations outside the ED, and a new surveillance protocol was applied to determine the factors warranting quarantine, including symptoms, chest radiographic findings, and exposure to a source of infection. The incidence of ED closures decreased after the implementation of the revised triage and surveillance protocols.

CONCLUSION

Triage screening by emergency physicians and surveillance protocols with an externally located chest imaging facility were effective in the early isolation of COVID-19 patients. In future outbreaks of emerging infectious diseases, efforts should be focused toward the provision of continued ED treatment with the implementation of revised triage and surveillance protocols.

Changing human-sensible temperature in Korea under a warmer monsoon climate over the last 100 years

This study explores changes in means and extreme events of human-sensible temperature (HST), which is quantified by selective combination of Universal Apparent Temperature, Heat Index, and a new Wind Chill Index, in Korea for the last 100 years (1919-2018) and illustrates the synoptic patterns of the East Asian monsoon system (EAMS) for extreme HST events. The time series analyses show that HST has increased much faster than near-surface air temperature (AT) in winter due to decrease in wind chill as well as to increase in AT. On the other hand, HST in summer, which is higher than AT on average because of high humidity in monsoon climate, has increased at a slow rate compared with those in other seasons. However, more extremely hot, long-lasting HST events have been observed in recent decades, as in 1994, 2013, 2016, and 2018, with shorter recurrent intervals. Greater increases of HST than AT are more distinct in the southern region under maritime subtropical climate than in the temperate climate zone in the north in all seasons. Composite maps for multiple high or low HST extreme events reveal that a dipole pressure anomaly pattern, rather than the intensity at the center of these air masses, is more closely related to the frequency of extreme HST events in Korea: A west high-east low pattern in winter formed by the expansion of the Siberian High accompanying an intense migratory low pressure system, and a south high-north low pattern formed by the westward intrusion of the Northwest Pacific subtropical high in summer after earlier terminations of summer rainy period (Changma). These indicate that monitoring of changing EAMS's characteristics is crucial to the mitigation of potential damages caused by unprecedented HST extreme events in the warmer twenty-first century.

Comparing the neurologic outcomes of patients with out-of-hospital cardiac arrest according to prehospital advanced airway management method and transport time interval

OBJECTIVE

The incidences of prehospital advanced airway management by emergency medical technicians in South Korea are increasing; however, whether this procedure improves the survival outcomes of patients experiencing out-of-hospital cardiac arrest remains unclear. The present study aimed to investigate the association between prehospital advanced airway management and neurologic outcomes according to a transport time interval (TTI) using the Korean Cardiac Arrest Research Consortium database.

METHODS

We retrospectively analyzed the favorable database entries that were prospectively collected between October 2015 and December 2016. Patients aged 18 years or older who experienced cardiac arrest that was presumed to be of a medical etiology and that occurred prior to the arrival of emergency medical service personnel were included. The exposure variable was the type of prehospital airway management provided by emergency medical technicians. The primary endpoint was a favorable neurologic outcome.

RESULTS

Of 1,871 patients who experienced out-of-hospital cardiac arrest, 785 (42.0%), 121 (6.5%), and 965 (51.6%) were managed with bag-valve-mask ventilation, endotracheal intubation (ETI), and supraglottic airway (SGA) devices, respectively. SGAs and ETI provided no advantage in terms of favorable neurologic outcome in patients with TTIs ≥12 minutes (odds ratio [OR], 1.37; confidence interval [CI], 0.65-2.87 for SGAs; OR, 1.31; CI, 0.30-5.81 for ETI) or in patients with TTI <12 minutes (OR, 0.57; CI, 0.31-1.07 for SGAs; OR, 0.63; CI, 0.12-3.26 for ETI).

CONCLUSION

Neither the prehospital use of SGA nor administration of ETI was associated with superior neurologic outcomes compared with bag-valve-mask ventilation.

Giraffe translocation population viability analysis

Most populations of giraffes have declined in recent decades, leading to the recent IUCN decision to upgrade the species to Vulnerable status, and some subspecies to Endangered. Translocations have been used as a conservation tool to re-introduce giraffes to previously occupied areas or establish new populations, but guidelines for founding populations are lacking. To provide general guidelines for translocation projects regarding feasibility, we simulated various scenarios of translocated giraffe populations to identify viable age and sex distributions of founding populations using population viability analysis (PVA) implemented in Vortex software. We explored the parameter space for demography and the genetic load, examining how variation in founding numbers and sex ratios affected 100 yr probability of population extinction and genetic diversity. We found that even very small numbers of founders (N ≤ 10 females) can appear to be successful in the first decades due to transient positive population growth, but with moderate population growth rate and moderate genetic load, long-term population viability (probability of extinction <0.01) was only achieved with ≥30 females and ≥3 males released. To maintain >95% genetic diversity of the source population in an isolated population, 50 females and 5 males are recommended to compose the founding population. Sensitivity analyses revealed first-year survival and reproductive rate were the simulation parameters with the greatest proportional influence on probability of extinction and genetic diversity. These simulations highlight important considerations for translocation success and data gaps including true genetic load in wild giraffe populations.

A simple blood preparation method for nucleic acid amplification tests using membranes

BACKGROUND

To detect most of bloodborne pathogens, serum must be separated from whole blood for efficient nucleic acid amplification. Centrifugation is the most commonly used preparation step for whole blood, but it is not easy to use a centrifuge in rural areas where electricity is not accessible.

OBJECTIVE

This study aimed to develop a simple method for obtaining serum suitable for nucleic acid amplification without the use of any instruments.

METHODS

Whole blood spiked with Escherichia coli (E. coli) was separated into serum and cellular fraction using 2 closely attached membranes with different characteristics. After brief heating, bacterial DNA in the serum was used for polymerase chain reaction (PCR).

RESULTS

Serum was successfully separated from cellular fraction after filtration of one membrane sheet. Membrane sheet containing serum was heated and bacterial DNA in the serum was used for PCR. The quality and concentration of DNA in the heated serum was sufficient for PCR and amplified E. coli gene products were observed.

CONCLUSIONS

Separation of bacteria-containing serum was feasible using two membrane sheets and the DNA isolated from serum can be used for PCR after brief heating.

Application of a Dual-Dispatch System for Out-of-Hospital Cardiac Arrest Patients: Will More Hands Save More Lives?

BACKGROUND

Recovery after out-of-hospital cardiac arrest (OHCA) is difficult, and emergency medical services (EMS) systems apply various strategies to improve outcomes. Multi-dispatch is one means of providing high-quality cardiopulmonary resuscitation (CPR), but no definitive best-operation guidelines are available. We assessed the effects of a basic life support (BLS)-based dual-dispatch system for OHCA.

METHODS

This prospective observational study of 898 enrolled OHCA patients, conducted in Daegu, Korea from March 1, 2015 to June 30, 2016, involved patients > 18 years old with suspected cardiac etiology OHCA. In Daegu, EMS started a BLS-based dual-dispatch system in March 2015, for cases of cardiac arrest recognition by a dispatch center. We assessed the association between dual-dispatch and OHCA outcomes using multivariate logistic regressions. We also analyzed the effect of dual-dispatch according to the stratified on-scene time.

RESULTS

Of 898 OHCA patients (median, 69.0 years; 65.5% men), dual-dispatch was applied in 480 (53.5%) patients. There was no difference between the single-dispatch group (SDG) and the dual-dispatch group (DDG) in survival at discharge and neurological outcomes (survival discharge, P = 0.176; neurological outcomes, P = 0.345). In the case of less than 10 minutes of on-scene time, the adjusted odds ratio was 1.749 (95% confidence interval [CI], 0.490-6.246) for survival discharge and 6.058 (95% CI, 1.346-27.277) for favorable neurological outcomes in the DDG compared with the SDG.

CONCLUSION

Dual-dispatch was not associated with better OHCA outcomes for the entire study population, but showed favorable neurological outcomes when the on-scene time was less than 10 minutes.

New Termination-of-Resuscitation Models and Prognostication in Out-of-Hospital Cardiac Arrest Using Electrocardiogram Rhythms Documented in the Field and the Emergency Department

BACKGROUND

Electrocardiogram (ECG) rhythms, particularly shockable rhythms, are crucial for planning cardiac arrest treatment. There are varying opinions regarding treatment guidelines depending on ECG rhythm types and documentation times within pre-hospital settings or after hospital arrivals. We aimed to determine survival and neurologic outcomes based on ECG rhythm types and documentation times.

METHODS

This prospective observational study of 64 emergency medical centers was performed using non-traumatic out-of-hospital cardiac arrest registry data between October 2015 and June 2017. From among 4,608 adult participants, 4,219 patients with pre-hospital and hospital ECG rhythm data were enrolled. Patients were divided into 3 groups: those with initial-shockable, converted-shockable, and never-shockable rhythms. Patient characteristics and survival outcomes were compared between groups. Further, termination of resuscitation (TOR) validation was performed for 6 combinations of TOR criteria confirmed in previous studies, including 2 rules developed in the present study.

RESULTS

Total survival to discharge after cardiac arrest was 11.7%, and discharge with good neurologic outcomes was 7.9%. Survival to discharge rates and favorable neurologic outcome rates for the initial-shockable group were the highest at 35.3% and 30.2%, respectively. There were no differences in survival to discharge rates and favorable neurologic outcome rates between the converted-shockable (4.2% and 2.0%, respectively) and never-shockable groups (5.7% and 1.9%, respectively). Irrespective of rhythm changes before and after hospital arrival, TOR criteria inclusive of unwitnessed events, no pre-hospital return of spontaneous circulation, and asystole in the emergency department best predicted poor neurologic outcomes (area under the receiver operating characteristic curve of 0.911) with no patients classified as Cerebral Performance Category 1 or 2 (specificity = 1.000).

CONCLUSION

Survival outcomes and TOR predictions varied depending on ECG rhythm types and documentation times within pre-hospital filed or emergency department and should, in the future, be considered in treatment algorithms and prognostications of patients with out-of-hospital cardiac arrest.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03222999.

Comparison of traffic collision victims between older and younger drivers in South Korea: Epidemiologic characteristics, risk factors and types of collisions

Objective

This study aimed to show the epidemiological characteristics and the difference in the risk factors and types of collision between older and younger drivers in Korea.

Methods

We collected data from the Emergency Department-based Injury In-depth Surveillance retrieved by the Korea Centers for Disease Control and Prevention from 2011 to 2015. We included injured drivers aged ≥ 18 years who were registered in the database, who were limited to drivers of four-wheeled vehicles. The enrolled patients were divided according to age into older (≥ 65 years) and younger (< 65 years) drivers. The total number of enrolled drivers was 37,511; 2,361 (6.3%) of them were older drivers. The epidemiological characteristics (e.g., age, sex, fatality rate) of traffic collision victims for 5 years were determined, and the risk factors (e.g., seat belt use) and types of collision (single- vs. multi-vehicle) between the two groups were compared.

Results

The median age and interquartile range (IQR; 25^th and 75^th percentiles) of all drivers were 41.0 (IQR, 32.0–52.0), and 24,544 (65.4%) of them were men. The median age increased from 40.0 (IQR, 31.0–50.0) to 43.0 (IQR, 33.0–54.0) between 2010 and 2015 (P < 0.001). The proportion of older drivers increased from 5.0% to 8.4% annually during the study period (P < 0.001). Between 2010 and 2015, the fatality rate decreased from 3.1% to 1.2% (P = 0.287) for older drivers and from 0.9% to 0.5% (P = 0.009) for younger drivers. The proportion of single-vehicle collision (25.9% vs. 20.3%) was higher in older than in younger drivers (P < 0.001). Older drivers had a lower rate of seat-belt use than younger drivers (79.0% vs. 83.0%, P < 0.001).

Conclusions

The proportion of older drivers increased annually during the study period, and older drivers experienced more single-vehicle collision and used seat belt less frequently than younger drivers. A national policy support to reduce traffic collision in older drivers and public relation activities to enhance their seat belt use should be strengthened in the future.

Hairline Lowering Surgery With Bone Tunneling Suture Fixation: Effectiveness and Safety in 91 Patients

BACKGROUND

People with a wide forehead often look older. Hairline lowering surgery is a good treatment option, which is generally performed utilizing Endotine.

OBJECTIVES

We describe our hairline lowering surgical technique involving bone tunneling without Endotine, a method designed to produce comparable outcomes with fewer side effects. We evaluated the effectiveness and safety of our technique.

METHODS

Charts of 91 patients who underwent hairline lowering surgery without Endotine were reviewed retrospectively. We utilized standardized preoperative and postoperative photographs to measure the proportions of 3 face parts and the length of the forehead. We also determined changes in forehead length at various times after surgery, occurrence of postoperative complications, and overall patient satisfaction with their surgical results.

RESULTS

Of the 91 patients, 80 were female and the mean age was 28.67 ± 7.15 years. Preoperatively, the mean forehead length was 8.09 ± 0.69 cm and ratio of facial part lengths was 1.08:1:0.99 (cranial to caudal). The hairline was advanced 18.37 ± 2.90 mm. One month postoperatively, the mean forehead length was 6.57 ± 0.52 cm and facial parts ratio was 1:1:0.99. Compared with preoperatively, forehead length was significantly reduced at 1, 3, 6, and 12 months postoperatively. Forehead length was not significantly different at 1 and 12 months postoperatively. All patients were satisfied or very satisfied with their overall surgical results.

CONCLUSIONS

Hairline lowering surgery with bone tunneling was effective and safe, and patients were satisfied with the results. The effects appeared immediately following surgery and were sustained over time.

LEVEL OF EVIDENCE: 4

Modeling of prognostication based on genomic expression in the tumor microenvironment of muscle invasive urothelial carcinoma via machine learning

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Background: Stroma in the tumor microenvironment (TME) influences prognosis and response to therapy. Few mathematical models exist to prognosticate patients (pts), based on mRNA expressivity in the TME. Methods: Clinical outcomes data and mRNA-seq of 401 pts with muscle invasive urothelial carcinoma were obtained from TCGA. Expressivity of 191 genes enriched in cellular and structural elements of TME and clinical data were analyzed by Kaplan-Meier (KM) analysis, correlation analysis, and multivariate nonlinear regression assisted by machine learning to achieve confined optimization with model-data minimization among multiple distribution functions. Results: Prognostication was modeled with higher risk score (RS) representing worse prognosis in stage 2-4 (Table, stage 1 data not available from TCGA). P/G is the ratio of genes associated with poor (19 genes) to good (11) prognosis (refer to presentation). Based on RS, pts in each stage were clustered into 2 groups (high and low RS), showing 2 KM curves with p < 0.01 in each stage, confirming the validity of RS modeling. Analysis of immune profiles in these 2 groups shows that regardless of stage, expression of genes associated with Desmoplasia, Angiogenesis, and Epithelial-mesenchymal transition (DAE) is higher in high RS groups. Furthermore, expression of DEA genes in stage 4 correlated more strongly with poor prognosis than observed in stage 2-3 as evidenced by smaller p-value. Among stage 4 tumors, expression of genes related to IFN response, NK cells, and T1 helper cells is higher in low RS groups. In stage 2 and 3, genes related to immune activation and inhibition have no association with prognosis (p > 0.05). Conclusions: Machine learning-assisted mathematical modeling of RS and gene analysis show that genes related to immune activation are associated with better prognosis, while DAE genes correlate with poorer prognosis among advanced stages. RS enables prognostication of pts encountered in the clinic, given genomic profiles. [Table: see text]

Modeling of prognostication and differential genomic expression in the tumor microenvironment of clear cell renal cell carcinoma

557

Background: Stroma in the tumor microenvironment (TME) influences prognosis and response to therapy. Few mathematical models exist to prognosticate patients (pts), based on mRNA expressivity in the TME. Methods: Clinical outcomes data and mRNA-seq of 533 pts with clear cell renal cancer were obtained from TCGA. Expressivity of 191 genes enriched in cellular and structural elements of TME and clinical data were analyzed via machine learning, multivariate nonlinear regression with confined optimization, and Kaplan-Meier (KM) analysis. Results: Prognostication was modeled with higher risk score (RS) representing worse prognosis in each stage (Table). P/G is the ratio of genes associated with poor (61 genes) to good (14) prognosis (refer to presentation). Based on RS, pts in each stage were clustered into 2 groups (high and low RS), showing 2 KM curves with p < 0.001 in each stage. Analysis of immune profiles in these 2 groups shows that in stage 1, expression of genes related to immune activation (IA) is not statistically different in high and low RS groups, but expression of genes related to immune inhibition (II) is higher in high RS group. In high RS groups of stage 2-4, IA genes are highly co-expressed with II genes. In high RS groups of all stages, expression of both IA and II genes increases as stage increases. In low RS groups, IA genes increase as stage increases, but II genes do not. Conclusions: Machine learning and mathematical modeling of RS and gene analysis show that IA genes are suppressed by high degree of II in high RS groups of advanced stages, contributing to worse prognosis. RS enables prognostication of pts encountered in the clinic, given genomic profiles. [Table: see text]

High-resolution rotational Raman spectroscopy of benzene

We present a rotational Raman spectrum for benzene with single-MHz resolution, more than a 100-fold improvement on literature data and sufficient to partially resolve K-splitting in some bands. Spectra for a frequency range of 0 to 500 GHz were measured through the observation of a coherent rotational wave packet in the time domain over a time scale of 1 microsecond. Spectroscopic frequencies were referenced to a GPS-stabilized clock. Fitted molecular constants of B = 5689.2671(±52) MHz, DJ = 1178(±50) Hz, and DJK = -2300(±120) Hz agree with results from some high-resolution rovibrational and rovibronic spectra but contradict others.

Comparison of different methods of RNA preparation from peripheral blood for nucleic acid amplification assay

Background

Nucleic acid amplification assays (NAAs), such as polymerase chain reaction or loop-mediated isothermal amplification (LAMP), are used for disease diagnosis. Current nucleic acid isolation kits require several hours for completion of protocol including the complicated handling steps.

Objective

In this study, a simple and cost-effective nucleic acid preparation method was developed, and its performance was compared with those of commercial kits.

Materials and Methods

RNA was prepared using our method and three commercial RNA isolation kits. The RNA quantity and quality were evaluated using the NanoDrop spectrophotometer and Agilent 2100 bioanalyser. Reverse transcription LAMP (RT-LAMP) reactions were performed to determine the usability of the RNA preparation methods.

Results

The concentrations of RNA extracted from blood samples by four different methods were sufficient for use in NAAs. The RNA integrity number was> 7.0 when RNA was isolated using other RNA isolation kits but lower when prepared using our method. The RT-LAMP reaction was successfully performed when RNA was prepared using any of the methods.

Conclusions

These results demonstrate that despite the lower purity and integrity of RNA, our RNA preparation protocol is simple and rapid and shows reasonable performance in RT-LAMP.

A comparative study of three different gene expression analysis methods

BACKGROUND

TNF-α regulates immune cells and acts as an endogenous pyrogen. Reverse transcription polymerase chain reaction (RT-PCR) is one of the most commonly used methods for gene expression analysis. Among the alternatives to PCR, loop-mediated isothermal amplification (LAMP) shows good potential in terms of specificity and sensitivity.

OBJECTIVE

However, few studies have compared RT-PCR and LAMP for human gene expression analysis. Therefore, in the present study, we compared one-step RT-PCR, two-step RT-LAMP and one-step RT-LAMP for human gene expression analysis.

METHODS

We compared three gene expression analysis methods using the human TNF-α gene as a biomarker from peripheral blood cells. Total RNA from the three selected febrile patients were subjected to the three different methods of gene expression analysis.

RESULTS

In the comparison of three gene expression analysis methods, the detection limit of both one-step RT-PCR and one-step RT-LAMP were the same, while that of two-step RT-LAMP was inferior. One-step RT-LAMP takes less time, and the experimental result is easy to determine.

CONCLUSIONS

One-step RT-LAMP is a potentially useful and complementary tool that is fast and reasonably sensitive. In addition, one-step RT-LAMP could be useful in environments lacking specialized equipment or expertise.

Long-term prognostic impact of osteopontin and Dickkopf-related protein 1 in patients with hepatocellular carcinoma after hepatectomy

BACKGROUND

New biomarkers are essential for improving the prediction of the survival and prognosis of patients with hepatocellular carcinoma (HCC). Alpha-fetoprotein (AFP) is the most widely used biomarker, but the low sensitivity and specificity limit its clinical applications. The diagnostic and prognostic capabilities of osteopontin (OPN), dickkopf-related protein 1 (DKK1), and a combination of these biomarkers are being studied.

METHODS

From January 2006 to December 2008, patients undergoing hepatectomy for HCC were screened and their serum stored in tumor banks was analyzed. The serum was used to investigate OPN and DKK1 levels by enzyme-linked immunosorbent assay(ELISA). In the paraffin block, the status of OPN and DKK1 positivity was assessed using immunohistochemistry(IHC).

RESULTS

A total of 60 patients were enrolled. The optimal cut-off level for survival was identified as 3.0 ng/mL and 5.2 ng/mL of OPN and DKK1, respectively. In multivariate analysis, a high OPN level was the only significant prognostic factor for overall survival [hazard ratio3.79, p = .017]. Considering a combination of AFP (cut-off level, 200 ng/mL) and OPN/DKK1, the patients with high AFP and OPN/DKK1 levels showed significantly lower overall survivals than those with low AFP, high AFP, and low OPN/DKK1 levels (p = .0091 for the AFP and OPN group, p = .0344 for the AFP and DKK1 group). Comparison between IHC and ELISA results for OPN and DKK1 levels did not reveal any significant correlation.

CONCLUSIONS

Serum OPN and DKK1 levels of HCC patients could be considered as novel biomarkers showing prognostic significance after hepatectomy based on long-term survival data.

Probability of Early Retirement Among Emergency Physicians

OBJECTIVES

Early retirement occurs when one's job satisfaction suffers due to employment mismatch resulting from factors such as inadequate compensation. Medical doctors report high levels of job stress and burnout relative to other professionals. These levels are highest among emergency physicians (EPs), and despite general improvements in their working conditions, early retirement continues to become more common in this population. The purpose of this study was to identify the factors influencing EPs intention to retire early and to develop a probability equation for its prediction.

METHODS

A secondary analysis of data from the 2015 Korean Society of Emergency Physicians Survey was performed. The variables potentially influencing early retirement were organized into personal characteristics, extrinsic factors, and intrinsic factors. Logistic regression analysis was performed to identify risk factors and to develop a probability equation; these findings were then arranged in a nomogram.

RESULTS

Of the 377 survey respondents included in the analysis, 48.0% intended to retire early. Risk factors for early retirement included level of satisfaction with the specialty and its outlook, slanderous reviews, emergency room safety, health status, workload intensity, age, and hospital type. Intrinsic factors (i.e., slanderous reviews and satisfaction with the specialty and its outlook) had a stronger influence on early retirement than did extrinsic factors.

CONCLUSIONS

To promote career longevity among EPs, it is vital to improve emergency room safety and workload intensity, to enhance medical professionalism through a stronger vision of emergency medicine, and to strengthen the patient-doctor relationship.

Fast Adjustments of the Asian Summer Monsoon to Anthropogenic Aerosols

Anthropogenic aerosols are a major factor contributing to human-induced climate change, particularly over the densely populated Asian monsoon region. Understanding the physical processes controlling the aerosol-induced changes in monsoon rainfall is essential for reducing the uncertainties in the future projections of the hydrological cycle. Here we use multiple coupled and atmospheric general circulation models to explore the physical mechanisms for the aerosol-driven monsoon changes on different time scales. We show that anthropogenic aerosols induce an overall reduction in monsoon rainfall and circulation, which can be largely explained by the fast adjustments over land north of 20∘N. This fast response occurs before changes in sea surface temperature (SST), largely driven by aerosol-cloud interactions. However, aerosol-induced SST feedbacks (slow response) cause substantial changes in the monsoon meridional circulation over the oceanic regions. Both the land-ocean asymmetry and meridional temperature gradient are key factors in determining the overall monsoon circulation response.

Intracellular Protein Delivery System Using a Target-Specific Repebody and Translocation Domain of Bacterial Exotoxin

With the high efficacy of protein-based therapeutics and plenty of intracellular drug targets, cytosolic protein delivery in a cell-specific manner has attracted considerable attention in the field of precision medicine. Herein, we present an intracellular protein delivery system based on a target-specific repebody and the translocation domain of Pseudomonas aeruginosa exotoxin A. The delivery platform was constructed by genetically fusing an EGFR-specific repebody as a targeting moiety to the translocation domain, while a protein cargo was fused to the C-terminal end of the delivery platform. The delivery platform was revealed to efficiently translocate a protein cargo to the cytosol in a target-specific manner. We demonstrate the utility and potential of the delivery platform by showing a remarkable tumor regression with negligible toxicity in a xenograft mice model when gelonin was used as the cytotoxic protein cargo. The present platform can find wide applications to the cell-selective cytosolic delivery of diverse proteins in many areas.

Descending necrotizing mediastinitis after a trigger point injection

Descending necrotizing mediastinitis (DNM) is a rare form of mediastinal infection. Most cases are associated with esophageal rupture. DNM after a trigger point injection in the upper trapezius has not been described previously. We present a case of DNM after a trigger point injection in the upper trapezius. A 70-year-old man visited the emergency department with chest discomfort and fever after a trigger point injection in the left upper trapezius. Chest computed tomography showed evidence of DNM, and antibiotic therapy was immediately administered intravenously. Because of the risk of sudden death, poor prognosis due to underlying disease, and his age, he declined surgical treatment and died of septic shock. Although trigger point injections are generally considered safe, caution should be used in patients with an underlying disease or in the elderly. Early diagnosis, broad-spectrum antibiotics, and aggressive surgical management are essential to improve the prognosis.

Multi-National Banknote Classification Based on Visible-light Line Sensor and Convolutional Neural Network

Automatic recognition of banknotes is applied in payment facilities, such as automated teller machines (ATMs) and banknote counters. Besides the popular approaches that focus on studying the methods applied to various individual types of currencies, there have been studies conducted on simultaneous classification of banknotes from multiple countries. However, their methods were conducted with limited numbers of banknote images, national currencies, and denominations. To address this issue, we propose a multi-national banknote classification method based on visible-light banknote images captured by a one-dimensional line sensor and classified by a convolutional neural network (CNN) considering the size information of each denomination. Experiments conducted on the combined banknote image database of six countries with 62 denominations gave a classification accuracy of 100%, and results show that our proposed algorithm outperforms previous methods.

Ileocolic intussusception caused by a lipoma in an adult

Intussusception is rarely observed in adults. Adult cases account for only 5% of all cases of intussusceptions and almost 1%-5% of bowel obstruction cases. The etiology, presentation and management of intussusception in adults are different from those in children. The clinical presentation in adults often includes nonspecific signs and symptoms, thereby complicating differential diagnosis from other causes of abdominal pain. We report a 29-year-old Asian woman who visited our emergency department with complaints of fever associated with epigastric pain since one day. Abdominal computed tomography demonstrated ileocolic intussusception, and laparoscopic small bowel luminal mass resection was performed. Histopathology report confirmed a 3.5 cm × 2.7 cm submucosal lipoma in the terminal ileum. Sufficient vigilance and appropriate investigations are important for prompt diagnosis and surgical referral of patients to enable favorable outcomes. A computed tomography scan can be a helpful modality in establishing a diagnosis.