Changes of antioxidant enzymes in the kidney after cardiac arrest in the rat model

Globally, cardiac arrest (CA) is a leading cause of death and disability. Asphyxial CA (ACA)-induced kidney damage is a crucial factor in reducing the survival rate. The purpose of this study was to investigate the role of antioxidant enzymes in histopathological renal damage in an ACA rat model at different time points. A total of 88 rats were divided into five groups and exposed to ACA except for the sham group. To evaluate glomerular function and oxidative stress, serum levels of blood urea nitrogen (BUN) and creatinine (Crtn) and malondialdehyde (MDA) levels in renal tissues were measured. To determine histopathological damage, hematoxylin and eosin staining, periodic acid-Schiff staining, and Masson's trichrome staining were performed. Expression levels of antioxidant enzymes including superoxide dismutase-1 (SOD-1), superoxide dismutase-2 (SOD-2), catalase (CAT), and glutathione peroxidase (GPx) were measured by immunohistochemistry (IHC). Survival rate of the experimental rats was reduced to 80% at 6 h, 55% at 12 h, 42.9% at 1 day, and 33% at 2 days after return of spontaneous circulation. Levels of BUN, Crtn, and MDA started to increase significantly in the early period of CA induction. Renal histopathological damage increased markedly from 6 h until two days post-CA. Additionally, expression levels of antioxidant enzymes were significantly decreased at 6 h, 12 h, 1 day, and 2 days after CA. CA-induced oxidative stress and decreased levels of antioxidant enzymes (SOD-1, SOD-2, CAT, GPx) from 6 h to two days could be possible mediators of severe renal tissue damage and increased mortality rate.

Germline Cancer Testing in Unselected Patients with Gastric and Esophageal Cancers: A Multi-center Prospective Study

BACKGROUND AND AIMS

To determine prevalence and clinical utility of pathogenic germline variants (PGV) in gastric and esophageal cancer patients using universal genetic testing approach.

METHODS

We undertook a prospective study of germline sequencing using an > 80 gene next-generation sequencing platform among patients with gastric and esophageal cancers receiving care at Mayo Clinic Cancer Center between April 1, 2018, and March 31, 2020. Patients were not selected based on cancer stage, family history of cancer, ethnicity, or age. Family cascade testing was offered at no cost.

RESULTS

A total of 96 patients were evaluated. Median age was 66 years, 80.2% were male, 89.6% were white. Nearly 39% of the cohort had esophageal cancer, 35.4% gastric cancer and 26% gastroesophageal junction cancers. Approximately half (52%) of the patients had metastatic disease. Pathogenic germline variants (PGV) were detected in 15.6% (n = 15) patients. The prevalence of PGV was 10.8% in esophageal cancer, 17.6% in gastric cancer and 20% in gastroesophageal cancer. Eighty percent of patients with a positive result would not have been detected by screening with standard guidelines for genetic testing. Most PGV detected included genes with high and moderate penetrance related to DNA damage response including BRCA1, BRCA2, PALB2 and ATM.

CONCLUSIONS

Universal multi-gene panel testing in gastric and esophageal cancers was associated with detection of heritable mutations in 15% of patients. The majority of PGV would not be detected with current screening guidelines and are related to DNA damage response.

Increased salivary syndecan-1 level is associated with salivary gland function and inflammation in patients with Sjögren's syndrome

Objectives: Syndecan-1 (SDC-1), a transmembrane heparin sulphate proteoglycan predominantly expressed on epithelial cells, also exists in a soluble form through ectodomain shedding. SDC-1 expression and shedding may be modulated in the inflammatory milieu of primary Sjögren's syndrome (SS). We investigated SDC-1 expression in minor salivary glands (MSGs) and analysed the association between salivary or plasma levels of SDC-1 and clinical parameters in SS.Method: We measured salivary and plasma SDC-1 levels via an enzyme-linked immunosorbent assay and assessed the salivary flow rates (SFRs) in 70 patients with SS and 35 healthy subjects. Disease activity indices, serological markers, salivary gland scintigraphy, and MSG biopsy were evaluated in patients with SS.Results: SDC-1 expression was upregulated on ductal epithelial cells in inflamed salivary glands. Salivary SDC-1 levels in patients significantly exceeded those in healthy subjects [median (interquartile range) 49.0 (20.7-79.1) vs 3.7 (1.7-6.3) ng/mL, p < 0.001] and inversely correlated with SFRs (r = -0.358, p = 0.032) and ejection fractions of the parotid (r = -0.363, p = 0.027) and submandibular (r = -0.485, p = 0.002) glands in salivary gland scintigraphy. Plasma SDC-1 levels were significantly correlated with the EULAR Sjögren's Syndrome Disease Activity Index (r = 0.507, p < 0.001) and EULAR Sjögren's Syndrome Patient Reported Index (r = 0.267, p = 0.033). Focus scores were correlated with salivary SDC-1 levels (r = 0.551, p = 0.004).Conclusion: Salivary and plasma SDC-1 levels may constitute potential biomarkers for salivary gland function and disease activity, respectively, in SS.

Timing and clinical outcomes of tracheostomy in patients with COVID-19

In this retrospective multicentre cohort study that included 27 COVID-19 patients who underwent tracheostomy, the mean time between intubation and tracheostomy was 15.8 days and the negative conversion time of COVID-19 was 43.1 days. Eleven patients (40.7%) died of COVID-19 and the use of percutaneous dilatation tracheostomy was significantly associated with in-hospital death. Timely tracheostomy could be performed in COVID-19 patients, regardless of duration of intubation or positivity of COVID-19 test, with an open surgical tracheostomy as a preferable technique.

Current trend of accreditation within medical education

Currently, accreditation in medical education is a priority for many countries worldwide. The World Federation for Medical Education’s (WFME) launch of its 1st trilogy of standards in 2003 was a seminal event promoting accreditation in basic medical education (BME) globally. In parallel, the WFME also actively spearheaded a project to recognize accrediting agencies within individual countries. The introduction of competency-based medical education (CBME), with the 2 key concepts of entrusted professional activity and milestones, has enabled researchers to identify the relationships between patient outcomes and medical education. The recent data-driven approach to CBME has been used for ongoing quality improvement of trainees and training programs. The accreditation goal has shifted from the single purpose of quality assurance to balancing quality assurance and quality improvement. Although there are many types of postgraduate medical education (PGME), it may be possible to accredit resident programs on a global scale by adopting the concept of CBME. It will also be possible to achieve accreditation alignment for BME and PGME, which center on competency. This approach may also make it possible to measure accreditation outcomes against patient outcomes. Therefore, evidence of the advantages of costly and labor-consuming accreditation processes will be available soon, and quality improvement will be the driving force of the accreditation process.

Governance system of the British Medical Association

It is regrettable that in recent years, the Korean Medical Association (KMA) has held special meetings of the house of delegates almost annually, purely for the removal of the president of the KMA from his/her office. There could be several reasons for this, but the failure of communication caused by the fragmentation of the KMA’s governance structure may be a major contributing factor. It may therefore be helpful to benchmark the governance of other professional organizations like the British Medical Association (BMA) to identify differences in the practice of consensus building, which leads to policy making. Due to the unexpected COVID-19 (coronavirus disease 2019) outbreak, this study was limited to internet resources. It was impossible for the author to conduct participant observation or direct face-toface interviews to get essential information about the governance of the BMA. Nevertheless, the findings provide valuable lessons for the KMA. There seem to be chasms among the house of delegates, the regional association and the board of directors in the KMA; better integration among major bodies within the KMA is required. Furthemore, the time spent by these bodies on generating policies and strategies is not sufficient. The BMA is a union with its professional activities secured by labor laws, whereas major players of the KMA do not have a protected time for their professional trade association. The KMA needs to remodel the current governance which is characterized by inadequate communication and subsequent fragmentation among the acting bodies of the Association. Continuous professional development for the leaders and members of the KMA might enable this change in governance.

Improving the Korean Medical Association’s organizational strength and partnership for physicians

The Korean Medical Association (KMA) was established by legal mandate. It is a statutory body for the medical profession. However, the collective dimension of professionalism is a foreign concept for Korean doctors; the KMA is perceived as a fraternity of physicians. Korea’s history of medical professionalization is different from that of Western countries where two different kinds of professional organization have developed: one for the public as a regulator and the other for doctors as a union or trade association. The KMA represents doctors nationally assembled by type of practice, geographic location, and function. Consequently, the KMA became a trade association. However, it is not easy for the KMA to serve two conflicting functions of self-regulation and trading body under one umbrella. It is time for the KMA to build up the organizational strength for the sake of doctors as well as the public. Having a sound trade association is a part of medical professionalism; it can advocate the critical value of medicine against undue influences from employers or governments in the era of industrialization and commercialization of medicine. To achieve this goal, the KMA should revamp its troublesome communication structure regarding its governance. Improving integration among key acting bodies within the KMA can streamline management by better communication. Preventing political feudalism to build consensus within the KMA requires new competencies for the leaders as well as the members of the KMA.

Intrinsically p-type cuprous iodide semiconductor for hybrid light-emitting diodes

Cuprous halides, characterized by a direct wide band-gap and a good lattice matching with Si, is an intrinsic p-type I-VII compound semiconductor. It shows remarkable optoelectronic properties, including a large exciton binding energy at room temperature and a very small piezoelectric coefficient. The major obstacle to its application is the difficulty in growing a single-crystal epitaxial film of cuprous halides. We first demonstrate the single crystal epitaxy of high quality cuprous iodide (CuI) film grown on Si and sapphire substrates by molecular beam epitaxy. Enhanced photoluminescence on the order of magnitude larger than that of GaN and continuous-wave optically pumped lasing were found in MBE grown CuI film. The intrinsic p-type characteristics of CuI were confirmed using an n-AlGaN/p-CuI junction that emits blue light. The discovery will provide an alternative way towards highly efficient optoelectronic devices compatible with both Si and III-nitride technologies.

Recurrence following hemithyroidectomy in patients with low- and intermediate-risk papillary thyroid carcinoma

BACKGROUND

This study evaluated the incidence, patterns and risk factors for recurrence after hemithyroidectomy in patients with low- and intermediate-risk papillary thyroid carcinoma (PTC), and verified the predictive role of the risk staging systems in current use.

METHODS

The clinicopathological characteristics and risk categories were analysed according to recurrence in patients who underwent hemithyroidectomy for low- and intermediate-risk conventional PTC, and were followed up for at least 24 months. Five risk staging systems were used to stratify risk: the 2015 American Thyroid Association (ATA) system; Age, Metastases, Extent and Size (AMES) system; Metastases, Age, Complete resection, Invasion and Size (MACIS) system; Grade, Age, Metastases, Extent and Size (GAMES) system; and the eighth AJCC system.

RESULTS

The study included 561 patients; 93·9 per cent of the study population (527 of 561) had a papillary thyroid microcarcinoma 1 cm or smaller in size. At a mean follow-up of 83 months, 25 patients (4·5 per cent) had recurrence; among these patients, 23 (92%) presented with a remaining thyroid lobe. Multifocality was significantly associated with recurrence in univariable and multivariable analyses (adjusted hazard ratio 3·16, 95 per cent c.i. 1·25 to 7·98; P = 0·015). Disease-free survival (DFS) varied according to multifocality (P = 0·010). The five risk staging systems were not associated with recurrence, and their Harrell's C-index ranged from 0·500 to 0·531. DFS rates did not differ between the risk categories in each system.

CONCLUSION

Although the recurrence rate after hemithyroidectomy in patients with low- and intermediate-risk PTC was low, meticulous follow-up focusing on the remaining thyroid lobe is needed for early detection and timely management of recurrence. The risk scoring systems in current use have no predictive role in these patients.

Characteristics and clinical assessment of antibiotic delivery by chitosan sponge in the high-risk diabetic foot: a case series

OBJECTIVE

The local delivery of antimicrobials is attractive for a number of reasons. Chitosan, a biodegradable polysaccharide sponge material, has been proposed as medium to deliver antibiotics directly to wounds. In this report we evaluate the safety and practicality of antimicrobial delivery via chitosan sponge.

METHOD

We present the clinical course and systemic absorption characteristics of three cases of people with diabetic foot wounds treated with antibiotic soaked chitosan sponge (Sentrex BioSponge, Bionova Medical, Germantown, TN). The antibiotic sponge was made by reconstituting 1.2g tobramycin or 100mg doxycycline in 10-15ml saline and saturating the sponge with the solution. The sponge was then applied to the wounds. Serum levels of each respective antibiotic were evaluated after application. Additional in vitro studies were conducted evaluating elution of antibiotics from the chitosan sponge at established minimum inhibitory concentrations (MIC) for Staphylococcus aureus over 28 days.

RESULTS

No patient experienced adverse local or systemic effects due to the sponge treatment. The measured serum levels applied antibiotics remained far less than established minimums after intravenous therapy. Each patient required further treatment, however local infection or contamination resolved during the course of their hospital stay after the chitosan/antibiotic application.

CONCLUSION

The use of antibiotic-impregnated chitosan sponges appears a safe and effective mechanism of local delivery of antimicrobials in wounds. Future studies and clinical trials are ongoing to confirm these results and to guide clinical applications.

Adaptive Compressive Tomography with No a priori Information

Quantum state tomography is both a crucial component in the field of quantum information and computation and a formidable task that requires an incogitable number of measurement configurations as the system dimension grows. We propose and experimentally carry out an intuitive adaptive compressive tomography scheme, inspired by the traditional compressed-sensing protocol in signal recovery, that tremendously reduces the number of configurations needed to uniquely reconstruct any given quantum state without any additional a priori assumption whatsoever (such as rank information, purity, etc.) about the state, apart from its dimension.

The "Glocalization" of Medical School Accreditation: Case Studies From Taiwan, South Korea, and Japan

PURPOSE

In an age of globalized medical education, medical school accreditation has been hailed as an approach to external quality assurance. However, accreditation standards can vary widely across national contexts. To achieve recognition by the World Federation for Medical Education (WFME), national accrediting bodies must develop standards suitable for both local contexts and international recognition. This study framed this issue in terms of "glocalization" and aimed to shine light on this complicated multistakeholder process by exploring accreditation in Taiwan, South Korea, and Japan.

METHOD

This study employed a comparative case-study design, examining the national standards that three accreditation bodies in East Asia developed using international reference standards. In 2015-2016, the authors conducted document analysis of the English versions of the standards to identify the differences between the national and international reference standards as well as how and why external standards were adapted.

RESULTS

Each country's accreditation body sought to balance local needs with global demands. Each used external standards as a template (e.g., Liaison Committee on Medical Education, General Medical Council, or WFME standards) and either revised (Taiwan, South Korea) or annotated (Japan) the standards to fit the local context. Four categories of differences emerged to account for how and why national standards departed from external references: structural, regulatory, developmental, and aspirational.

CONCLUSIONS

These countries' glocalization of medical accreditation standards serve as examples for others seeking to bring their accreditation practices in line with global standards while ensuring that local values and societal needs are given adequate consideration.

Two different phase-change origins with chemical- and structural-phase-changes in C doped (1.5 wt.%) In3Sb1Te2

We fabricated C-doped (1.5 wt.%) In₃Sb₁Te₂ (CIST) thin films with amorphous phase (a-CIST) using a sputter method. Two electrical-phase-changes at 250 and 275 °C were observed in the sheet resistance measurement. In order to understand the origin of these electrical-phase-changes, all samples were characterized by XRD, TEM, and HRXPS with synchrotron radiation. In a-CIST, only weak Sb-C bonding was observed. In the first electrical-phase-change at 250 °C, strong Sb-C bonding occurred without an accompanying structural/phase change (still amorphous). On the other hand, the second electrical-phase-change at 275 °C was due to the structural/phase change from amorphous to crystalline without a chemical state change.

Learners' perspective: where and when pre-residency trainees learn more to achieve their core clinical competencies

PURPOSE

While it is known that effective clinical education requires active involvement of its participants, regular feedback, communication skills and interprofessional training, limited studies have been conducted in Korea that demonstrate how pre-residency trainees acquire their core clinical skills. This is a cross-sectional study of interns and students across a third-tier university hospital in Korea to examine where and when they acquire core clinical skills.

METHODS

A total of 74 students and 91 interns were asked to participate in a closed-ended questionnaire, and 50 participants (20 students and 30 interns) were involved in semistructured individual interviews. The questionnaire was based on the Accreditation Council for Graduate Medical Education core competencies.

RESULTS

The majority of core clinical skills were acquired during their rotations in emergency medicine, general surgery, and cardiothoracic surgery. The semistructured interviews revealed that these departments required their trainees to be highly involved and analytical, and participate in clinical discourse.

CONCLUSION

The common factor among the three departments is an environment in which trainees are highly involved in clinical duties, and are expected to make first-contact patient encounters, participate in clinical discourse, interpret investigative results and arrive at their own conclusions. Work-based learning appear to be key to the trends observed, and further study is warranted to determine whether these findings are indicative of true acquisition of clinical competence.

Continuous quality improvement in an accreditation system for undergraduate medical education: Benefits and challenges

BACKGROUND

Accreditation reviews of medical schools typically occur at fixed intervals and result in a summative judgment about compliance with predefined process and outcome standards. However, reviews that only occur periodically may not be optimal for ensuring prompt identification of and remediation of problem areas.

AIMS

To identify the factors that affect the ability to implement a continuous quality improvement (CQI) process for the interval review of accreditation standards.

METHODS

Case examples from the United States, Canada, the Republic of Korea and Taiwan, were collected and analyzed to determine the strengths and challenges of the CQI processes implemented by a national association of medical schools and several medical school accrediting bodies. The CQI process at a single medical school also was reviewed.

RESULTS

A functional CQI process should be focused directly on accreditation standards so as to result in the improvement of educational quality and outcomes, be feasible to implement, avoid duplication of effort and have both commitment and resource support from the sponsoring entity and the individual medical schools.

CONCLUSIONS

CQI can enhance educational program quality and outcomes, if the process is designed to collect relevant information and the results are used for program improvement.

Perception of interprofessional conflicts and interprofessional education by doctors and nurses

PURPOSE

This study aimed to collect information that is needed to develop interprofessional education curricula by examining the current status of interprofessional conflicts and the demand for interprofessional education.

METHODS

A total of 95 doctors and 92 nurses in three university hospitals in Seoul responded to a survey that comprised questions on past experience with interprofessional conflicts, the causes and solutions of such conflicts, past experience with interprofessional education, and the demand for interprofessional education.

RESULTS

We found that 86% of doctors and 62.6% of nurses had no interprofessional education experience. Most of them learned about the work of other health professions naturally through work experience, and many had experienced at least one interprofessional conflict. For doctors, the most popular method of resolving interprofessional conflicts was to let the event pass; for nurses, it was to inform the department head. Further, 41.5% of doctors and 56.7% of nurses expressed no knowledge of an official system for resolving interprofessional conflicts within the hospital, and 62.8% of doctors and 78.3% of nurses stated that they would participate in interprofessional education if the opportunity arose.

CONCLUSION

In Korean hospital organizations, many doctors and nurses have experienced conflicts with other health professionals. By developing an appropriate curriculum and educational training system, the opportunities for health professionals to receive interprofessional education should expand.

Only the chemical state of Indium changes in Mn-doped In3Sb1Te2 (Mn: 10 at.%) during multi-level resistance changes

We fabricated and characterized the material with Mn (10 at.%: atomic percent) doped In3Sb1Te2 (MIST) using co-sputtering and synchrotron radiation, respectively. The MIST thin film showed phase-changes at 97 and 320 °C, with sheet resistances of ~10 kΩ(sq) (amorphous), ~0.2 kΩ(sq) (first phase-change), and ~10 Ω(sq) (second phase-change). MIST did not exhibit any chemical separation or increased structural instability during either phase-change, as determined with high-resolution x-ray photoelectron spectroscopy. Chemical state changes were only depended for In without concomitant changes of Sb and Te. Apparently, doped Mn atoms can be induced with movement of only In atoms.

Clinical impact of microscopic extrathyroidal extension in patients with papillary thyroid microcarcinoma treated with hemithyroidectomy

BACKGROUND

Pathologically confirmed microscopic extrathyroidal extension (ETE) is often identified after hemithyroidectomy in patients with papillary thyroid microcarcinoma (PTMC). Without the presence of microscopic ETE, these patients would be optimal candidates for hemithyroidectomy.

AIM

The present study aimed at evaluating the clinical impact of microscopic ETE on the recurrence of PTMC treated with hemithyroidectomy.

SUBJECTS AND METHODS

We compared the clinicopathological characteristics and 5-year outcomes for 262 PTMC patients without ETE and 86 with microscopic ETE who were treated with hemithyroidectomy between January 2004 and December 2010.

RESULTS

The mean tumour size was larger (0.67 vs. 0.54 cm, p < 0.001) and the proportion of tumours measuring ≥0.5 cm was higher (84.9 vs. 66.8 %, p = 0.001) in patients with microscopic ETE as compared with patients without ETE. Occult multifocal disease was more frequent in patients with microscopic ETE than in those without ETE (14.0 vs. 6.5 %, p = 0.030). However, the recurrence rate was not different between the two groups during the mean 55.8-month follow-up period. In addition, univariate and multivariate analyses revealed no meaningful association between recurrence and microscopic ETE in patients with PTMC treated with hemithyroidectomy.

CONCLUSIONS

Although microscopic ETE was associated with large tumour size and multifocal disease, its clinical impact on disease recurrence was not significant in PTMC patients treated with hemithyroidectomy. Therefore, microscopic ETE identified after hemithyroidectomy would not be an absolute indication for completion thyroidectomy in patients with PTMC.

Beyond accreditation: excellence in medical education

Medical school accreditation is a relatively new phenomenon in Korea. The development of an accreditation body and standards for a two-tiered "Must" and "Should" system in 1997 eventually led to the implementation of a third "Excellence" level of attainment. These standards were conceived out of a desire to be able to first recognize and promote outstanding performance of medical schools, second to provide role models in medical education, and furthermore to preview the third level as potential components of the pre-existing second level for the next accreditation cycle. It is a quality-assurance mechanism that, while not required for accreditation itself, pushes medical schools to go beyond the traditional requirements of mere pass-or-fail accreditation adequacy, and encourages schools to deliver an unprecedented level of medical education. The Association for Medical Education in Europe developed its own third-tier system of evaluation under the ASPIRE project, with many similar goals. Due to its advanced nature and global scope, the Korean accreditation body has decided to implement the ASPIRE system in Korea as well.

Capsule endoscopy with PILLCAM ESO for detecting esophageal varices: a meta-analysis

AIM

The aim of the present study was to perform meta-analysis of studies that compare diagnostic capabilities of esophageal capsule endoscopy (ECE) against conventional esophago-gastro-duodenoscopy (EGD) in detecting esophageal varices.

METHODS

A literature search is done for studies that compared the performance of ECE and EGD in screening and surveillance of esophageal varices. Data was extracted to estimate the pooled sensitivity, pooled specificity, positive diagnostic ratio, negative diagnostic ratio and diagnostic odds ratio.

RESULTS

We included 9 studies and total number of patients was 631. There were 12 capsule failures so data was available for 619 patients. The pooled sensitivity and specificity of CE for detecting esophageal varices were 83% and 85% respectively. The pooled positive likelihood and negative likelihood ratios are 4.09 and 0.25, respectively. Pooled diagnostic odds ratio was 24.92.

CONCLUSION

In our meta- analysis PillCam ESO performed well in detecting esophageal varices but it was not comparable to EGD; it can be an acceptable alternative in certain situations but cannot be recommended to replace EGD.

Probing the continuous radio frequency spectrum of water relaxation using a carbon nanotube

We have obtained the continuous radio frequency spectrum of water molecule relaxation using carbon nanotubes (CNT) as a high-speed nanoprobe. Three sets of characteristic time scales are clearly identified. Two sets are attributed to the electric-field-driven polarization of water molecules bound to CNTs and the collective relaxation of water layers in the vicinity of CNTs, respectively. The third set is appreciable only in air, and can be related to triplet oxygen relaxation.