mRNA-encoded Cas13 treatment of Influenza via site-specific degradation of genomic RNA.

The CRISPR-Cas13 system has been proposed as an alternative treatment of viral infections. However, for this approach to be adopted as an antiviral, it must be optimized until levels of efficacy rival or exceed the performance of conventional approaches. To take steps toward this goal, we evaluated the influenza viral RNA degradation patterns resulting from the binding and enzymatic activity of mRNA-encoded LbuCas13a and two crRNAs from a prior study, targeting PB2 genomic and messenger RNA. We found that the genome targeting guide has the potential for significantly higher potency than originally detected, because degradation of the genomic RNA is not uniform across the PB2 segment, but it is augmented in proximity to the Cas13 binding site. The PB2 genome targeting guide exhibited high levels (>1 log) of RNA degradation when delivered 24 hours post-infection in vitro and maintained that level of degradation over time, with increasing multiplicity of infection (MOI), and across modern influenza H1N1 and H3N2 strains. Chemical modifications to guides with potent LbuCas13a function, resulted in nebulizer delivered efficacy (>1-2 log reduction in viral titer) in a hamster model of influenza (Influenza A/H1N1/California/04/09) infection given prophylactically or as a treatment (post-infection). Maximum efficacy was achieved with two doses, when administered both pre- and post-infection. This work provides evidence that mRNA-encoded Cas13a can effectively mitigate Influenza A infections opening the door to the development of a programmable approach to treating multiple respiratory infections.

Becoming a doctor: using social constructivism and situated learning to understand the clinical clerkship experiences of undergraduate medical students.

BACKGROUND: Despite the emphasis on the uniqueness and educational importance of clinical clerkships in medical education, there is a lack of deep understanding of their educational process and outcomes. Especially due to an inherent trait of clinical clerkships which requires participation in the workplace outside the classroom, it is difficult to fully comprehend their educational potential using traditional learning perspectives such as imbibing outside knowledge. Accordingly, this study aims to explore the experiences of a rotation-based clerkship of medical school students from the perspective of social constructivism of learning, which can empirically examine what and how medical students learn during clinical clerkship in South Korea. By providing an insight into the workings of the clerkship process, this study contributes to a better understanding of how a learning-friendly environment can be cultivated at clinical clerkships. METHODS: The study utilized a basic qualitative study to understand what and how medical students learn during their clinical clerkships. Semi-structured, in-depth individual interviews were conducted with eight sixth-graders who had experienced a two-year clerkship at Ajou University Medical School. Data were analyzed based on Lave and Wenger's situated learning theory and Wenger's social theory in learning. RESULTS: We found that the medical students had developed different aspects of their professional identities such as values, functionality, career decisions, sociality, and situating during their clinical clerkships. Further, professional identity was formed through a combination of participation and reification-the processes involved in the negotiation of meaning. This combination was facilitated by the students' first experience and relationships with professors, classmates, and patients. Finally, non-learning occurred in the context of over-participation (learning anxiety and alienation) or over-reification (evaluation and e-portfolio). CONCLUSIONS: This study revealed five sub-professional identities and their formation process from the learners' perspective, thereby uncovering the unique learning characteristics and advantages of rotated-based clerkship and contributing to a further understanding of how gradual improvements can be made to the traditional clerkship education of medical students.

Comparison of injectate spread and nerve coverage between single-injection intertransverse process block and paravertebral block at the T2 level: a cadaveric study.

BACKGROUND: We compared the spread of an injectate into the thoracic sympathetic chain resulting from a single-injection intertransverse process (ITP) block with that of a single-injection PV block at the T2 level. METHODS: Sixteen soft-embalmed cadavers were used. The right hemithorax was randomly allocated to receive either an ultrasound-guided single-injection ITP block or ultrasound-guided single-injection PV block at the T2 vertebral level, with the opposite block administered to the other side. Approximately 10 mL of latex dye solution was injected into each hemithorax using a random allocation technique. The presence of dye at the nerve root in the sympathetic chain and intercostal nerves at the injection and additional levels was examined by dissection. RESULTS: The injectate spread into the T2 sympathetic ganglion on both ITP (11/16, 68.8%) and PV (16/16, 100%) blocks. The ITP block demonstrated greater uniformity of dye staining in both the dorsal rami and dorsal root ganglion, which contrasts with the less consistent staining outcomes of the PV block in these regions. CONCLUSIONS: At the T2 level, we observed a lower efficacy of the ITP block for analgesic coverage of the sympathetic nerve. This suggested a potential preference by clinicians for the application of the T2 PV block over the ITP block, specifically for the management of sympathetically maintained pain in the upper extremities. In addition, our findings may hint at the potential advantages of the ITP block in specific clinical contexts where targeted nerve involvement, such as the medial branch block or dorsal root ganglion block, is sought.

Extracurricular activities in medical education: an integrative literature review.

BACKGROUND: The importance of extracurricular activities (EAs) has been emphasized in medical education. These activities could enhance medical students' emotional and physical health and afford them developmental opportunities. Despite the growing amount of research related to this theme, few studies review and synthesize the existing literature. This study aims to provide an understanding of the educational implications of EAs in medical colleges and constructs an integrated conceptual framework concerning their types and learning outcomes by literature review. METHODS: An integrative literature review was conducted following Torraco's method, with the aim to generate a new framework for the given topic. The authors utilized Scopus and PubMed as databases, using search terms "extracurricular," "medical," and "students." Initially, titles and abstracts were screened to include relevant studies, and the researchers verified the eligibility of the articles by following the inclusion and exclusion criteria. Of the 263 articles identified, 64 empirical studies were selected for further review. RESULTS: EAs in undergraduate medical education can be classified into direct extracurricular activities and indirect extracurricular activities, the latter of which is sorted into nine sub-categories. We identified seven main categories regarding the learning outcomes of EAs. In addition to general activities (e.g., pro-social activities, team sports), some distinctive activities such as research have been largely addressed in previous studies. The results of EAs were discussed in relation to academic growth, career development, and psychological experiences. CONCLUSIONS: This review identified the types and learning outcomes of EAs in the context of medical education, thereby suggesting ways to improve the quality of EAs and maximize their educational effects.

Reevaluating the Binge Eating Scale cut-off using DSM-5 criteria: analysis and replication in preoperative metabolic and bariatric surgery samples.

BACKGROUND: Metabolic and bariatric surgery is effective for sustained weight loss, but binge eating disorder (BED) can be associated with poorer outcomes and lead to weight regain. A common measure used to screen for BED is the Binge Eating Scale (BES). A BES cut-off score of ≥17 previously identified patients who have a high likelihood of meeting criteria for BED. The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), lowered the threshold for meeting criteria for BED, and the psychometrics of the BES need to be reevaluated. OBJECTIVE: The objective of the current investigation is to evaluate whether alternative cut-scores on the BES result in better classification of BED based on the DSM-5 revision of the the BED diagnostic criteria. SETTING: Academic medical hospital in the Midwestern United States. METHODS: Patients (n =1133) seeking metabolic and bariatric surgery were randomly split into 2 samples for validation and replication. The validation sample consisted of 561 patients (30.1% men, 35% non-White). The replication sample consisted of 572 patients who were demographically similar to the first random split sample (e.g., 25.3% men, 34.4% non-White). RESULTS: Of these patients, 13.5% met DSM-5 criteria for BED in the validation sample and 13.8% met criteria for BED in the replication sample. Lowering the interpretative cut-off to ≥15 on the BES yielded sensitivity values of >.72, specificity values of >.67, and an accurate classification of BED in >.70 of patients across both samples. These classification values were as good as or better than the standard cut-off score of ≥17 in both samples. CONCLUSIONS: The BES is appropriate to screen for BED in patients who are seeking bariatric surgery. A 2-point decrease in the BES score for clinical interpretation is appropriate-lowering it from 17 to 15 given DSM-5 updates to diagnostic criteria.

The Marine-Derived Natural Product Epiloliolide Isolated from Sargassum horneri Regulates NLRP3 via PKA/CREB, Promoting Proliferation and Anti-Inflammatory Effects of Human Periodontal Ligament Cells.

Currently, periodontitis treatment relies on surgical operations, anti-inflammatory agents, or antibiotics. However, these treatments cause pain and side effects, resulting in a poor prognosis. Therefore, in this study, we evaluated the impact of the compound epiloliolide isolated from Sargassum horneri on the recovery of inflammatory inhibitors and loss of periodontal ligaments, which are essential treatment strategies for periodontitis. Here, human periodontal ligament cells stimulated with PG-LPS were treated with the compound epiloliolide, isolated from S. horneri. In the results of this study, epiloliolide proved the anti-inflammatory effect, cell proliferation capacity, and differentiation potential of periodontal ligament cells into osteoblasts, through the regulation of the PKA/CREB signaling pathway. Epiloliolide effectively increased the proliferation and migration of human periodontal ligament cells without cytotoxicity and suppressed the protein expression of proinflammatory mediators and cytokines, such as iNOS, COX-2, TNF-α, IL-6, and IL-1ß, by downregulating NLRP3 activated by PG-LPS. Epiloliolide also upregulated the phosphorylation of PKA/CREB proteins, which play an important role in cell growth and proliferation. It was confirmed that the anti-inflammatory effect in PG-LPS-stimulated large cells was due to the regulation of PKA/CREB signaling. We suggest that epiloliolide could serve as a potential novel therapeutic agent for periodontitis by inhibiting inflammation and restoring the loss of periodontal tissue.

Nutritional Value of the Larvae of the Alien Invasive Wasp Vespa velutina nigrithorax and Amino Acid Composition of the Larval Saliva.

The systematic investigations on the value of social wasps as a food resource are deficient, in spite of the long history of the utilization of social wasps as food and pharmaceutical bioresources. Vespa velutina nigrithorax is an invasive alien wasp species that is currently dominating in East Asia and Europe, bringing huge economic damages. As a control over alien species is made when the valuable utilization of the invasive species as a potential resource are discovered, investigations on the potential of V. v. nigrithorax as a useful bioresource are also in demand. Nutritional and heavy metal analyses of the larvae revealed their balanced and rich nutritional value and safety as a food resource. The larval saliva amino acid composition was investigated for further study on amino acid supplementation and exercise enhancement.

Molecular epidemiology of community-associated antimicrobial-resistant Staphylococcus aureus in Seoul, Korea (2003): pervasiveness of multidrug-resistant SCCmec type II methicillin-resistant S. aureus.

There is an extremely high incidence of antimicrobial resistance of the clinical isolates of Staphylococcus aureus in Korea. This study carried out a molecular investigation to determine the prevalence of the community-associated antimicrobial-resistant S. aureus and methicillin-resistant S. aureus (MRSA). The percentage resistance from the nasal swabs of healthy volunteers in 2003 in Seoul is as follows: penicillin (91%), erythromycin (EM, 14%), gentamicin (GM, 9.3%), tetracycline (TE, 8.2%), cephalothin (4%), oxacillin (OX, MRSA; 3.8%), clindamycin (CC, 2.6%), ciprofloxacin (CIP, 0.8%), and sulfamethoxazole/trimethoprim (0.6%). The community-associated MRSA (C-MRSA) strains were examined by pulsed-field gel electrophoresis (PFGE) analysis of the SmaI macro-fragments, multilocus sequence typing (MLST), and staphylococcal cassette chromosome mec (SCCmec) typing using the PCR analysis. The Korean C-MRSA isolates were clustered into three distinct groups. One PFGE group containing the C-MRSA strains showed resistance to CC, EM, and GM, a high level (32-96 microg/ml) of resistance to methicillin, sequence type 5 (ST5), and SCCmec type II, which is the most common hospital associated-MRSA (H-MRSA) isolated in Korea. These results highlight the heterogeneous genetic background of the C-MRSA as well as the pervasiveness of the H-MRSA isolates in this community.

Modulation of adherence, invasion, and tumor necrosis factor alpha secretion during the early stages of infection by Streptococcus pneumoniae ClpL.

Heat shock proteins (HSPs) play a pivotal role as chaperones in the folding of native and denatured proteins and can help pathogens penetrate host defenses. However, the underlying mechanism(s) of modulation of virulence by HSPs has not been fully determined. In this study, the role of the chaperone ClpL in the pathogenicity of Streptococcus pneumoniae was assessed. A clpL mutant adhered to and invaded nasopharyngeal or lung cells much more efficiently than the wild type adhered to and invaded these cells in vitro, as well as in vivo, although it produced the same amount of capsular polysaccharide. However, the level of secretion of tumor necrosis factor alpha (TNF-alpha) from macrophages infected with the clpL mutant was significantly lower than the level of secretion elicited by the wild type during the early stages of infection. Interestingly, treatment of the human lung epithelial carcinoma A549 and murine macrophage RAW 264.7 cell lines with cytochalasin D, an inhibitor of actin polymerization, increased adherence of the mutant to the host cells. In contrast, cytochalasin D treatment of RAW 264.7 cells decreased TNF-alpha secretion after infection with either the wild type or the mutant. However, pretreatment of cell lines with the actin polymerization activator jasplakinolide reversed these phenotypes. These findings indicate, for the first time, that the ClpL chaperone represses adherence of S. pneumoniae to host cells and induces secretion of TNF-alpha via a mechanism dependent upon actin polymerization during the initial infection stage.