Understanding the biosynthesis of human IgM SAM-6 through a combinatorial expression of mutant subunits that affect product assembly and secretion.

Polymeric IgMs are secreted from plasma cells abundantly despite their structural complexity and intricate multimerization steps. To gain insights into IgM's assembly mechanics that underwrite such high-level secretion, we characterized the biosynthetic process of a natural human IgM, SAM-6, using a heterologous HEK293(6E) cell platform that allowed the production of IgMs both in hexameric and pentameric forms in a controlled fashion. By creating a series of mutant subunits that differentially disrupt secretion, folding, and specific inter-chain disulfide bond formation, we assessed their effects on various aspects of IgM biosynthesis in 57 different subunit chain combinations, both in hexameric and pentameric formats. The mutations caused a spectrum of changes in steady-state subcellular subunit distribution, ER-associated inclusion body formation, intracellular subunit detergent solubility, covalent assembly, secreted IgM product quality, and secretion output. Some mutations produced differential effects on product quality depending on whether the mutation was introduced to hexameric IgM or pentameric IgM. Through this systematic combinatorial approach, we consolidate diverse overlapping knowledge on IgM biosynthesis for both hexamers and pentamers, while unexpectedly revealing that the loss of certain inter-chain disulfide bonds, including the one between µHC and λLC, is tolerated in polymeric IgM assembly and secretion. The findings highlight the differential roles of underlying non-covalent protein-protein interactions in hexamers and pentamers when orchestrating the initial subunit interactions and maintaining the polymeric IgM product integrity during ER quality control steps, secretory pathway trafficking, and secretion.

Exploring susceptibility factors to medication dispensing errors through a retrospective study of patient-reported dispensing errors over 11 years: are dispensing errors indeed due to personal reasons for pharmacists?

BACKGROUND: Medication dispensing errors cause wastage of medicines and increase healthcare costs, with serious consequences for patients. However, few studies have systematically and completely reviewed dispensing errors, with inadequate attention to the objective regularity and risk factors for dispensing errors. OBJECTIVES: To explore the potential causes and risk factors influencing the prevalence of medication dispensing errors. METHODS: We collected patient-reported medication dispensing errors from a large tertiary care hospital in South China over 11 years. We assessed the characteristics of dispensing errors, labelled the causes, compared them with more than 25 million prescriptions from 2012 to 2022, identified the susceptibility factors for the occurrence of dispensing errors, and analysed the characteristics and patterns of the errors. RESULTS: A total of 376 patient-reported dispensing errors were recorded. It took an average of 5.2 days for a patient to find an error. Only 37.5% of errors were reviewed by the patient within 24 hours. These errors directly contributed to a medication loss of US$188 406. Of the 160 recorded pharmacists, 112 (70%) committed dispensing errors. Dispensing errors were affected by the pharmacists' use of the machine, workload and the length of monthly vacation. Of the dispensing errors, 47.9% (n=180) were caused by medication packaging or names that were similar. Antibiotics (n=32, 8.5%) were the most common types of drugs dispensed incorrectly, and traditional Chinese medicines (n=31, 8.2%) and immunosuppressants (n=21, 5.6%) were the most likely to be dispensed in inaccurate quantities. CONCLUSIONS: Organising adequate staff and using machines to prepare medicines may be necessary to reduce dispensing errors. When pharmacists have been away from work for more than 72 hours they should find their rhythm in other positions before dispensing medicines. It is more important to prioritise the differentiation of medicines with similar packaging over those with similar names when arranging drug shelving.

Development of in silico models to predict viscosity and mouse clearance using a comprehensive analytical data set collected on 83 scaffold-consistent monoclonal antibodies.

Biologic drug discovery pipelines are designed to deliver protein therapeutics that have exquisite functional potency and selectivity while also manifesting biophysical characteristics suitable for manufacturing, storage, and convenient administration to patients. The ability to use computational methods to predict biophysical properties from protein sequence, potentially in combination with high throughput assays, could decrease timelines and increase the success rates for therapeutic developability engineering by eliminating lengthy and expensive cycles of recombinant protein production and testing. To support development of high-quality predictive models for antibody developability, we designed a sequence-diverse panel of 83 effector functionless IgG1 antibodies displaying a range of biophysical properties, produced and formulated each protein under standard platform conditions, and collected a comprehensive package of analytical data, including in vitro assays and in vivo mouse pharmacokinetics. We used this robust training data set to build machine learning classifier models that can predict complex protein behavior from these data and features derived from predicted and/or experimental structures. Our models predict with 87% accuracy whether viscosity at 150 mg/mL is above or below a threshold of 15 centipoise (cP) and with 75% accuracy whether the area under the plasma drug concentration-time curve (AUC0-672 h) in normal mouse is above or below a threshold of 3.9 × 106 h x ng/mL.

Effects of Plant-Based Diets on Anthropometric and Cardiometabolic Markers in Adults: An Umbrella Review.

We conducted an umbrella review to consolidate the evidence of adopting plant-based diets on anthropometric and cardiometabolic outcomes. Six electronic databases (CINAHL, EMBASE, PubMed, Scopus, the Cochrane Library, and Web of Science) were searched for systematic reviews with meta-analysis (SRMAs) published from each journal's inception until 1 October 2022. Effect sizes from SRMAs and primary studies were pooled separately using random effects models. Overlapping primary studies were removed for primary studies' analyses. Seven SRMAs representing 51 primary studies were included, suggesting significant benefits of plant-based diets on weight (-2.09 kg, 95% CI: -3.56, -0.62 kg, p = 0.01, I2 = 95.6%), body mass index (-0.95 kg/m2, 95% CI: -1.26, -0.63 kg/m2, p = 0.002; I2 = 45.1%), waist circumference (-2.20 cm, 95% CI: -0.08, 0.00 cm, p = 0.04; I2 = 88.4%), fasting blood glucose (-0.11 mmol/L, 95% CI: -0.13, -0.09 mmol/L, p < 0.001, I2 = 18.2%), and low-density lipoprotein cholesterol (-0.31 mmol/L, 95% CI: -0.41, -0.20 mmol/L, p < 0.001, I2 = 65.6%). Changes in high-density lipoprotein cholesterol, triglycerides, and blood pressure were not statistically significant. Generally, plant-based diets were recommended to improve anthropometry, lipid profile, and glucose metabolism. However, findings should be interpreted with caution, because most of the reviews were rated to be of low credibility of evidence and were largely based on Western eating habits and traditions, which may limit the generalizability of findings.

Bleeding risk after acupuncture in patients taking anticoagulant drugs: A case control study based on real-world data.

OBJECTIVES: Patients on anticoagulant medications may be at a higher risk of bleeding after acupuncture. This study aimed to assess the association between anticoagulant drug use and bleeding after acupuncture. DESIGN: Case control study SETTING: We analysed the diagnosis and treatment records (2000-2018) of a random sample of two million patients from the National Health Insurance Research Database in Taiwan. INTERVENTIONS: anticoagulant and antiplatelet drugs MAIN OUTCOME MEASURES: The incidence rates of major (visceral bleeding or ruptured blood vessels requiring transfusion) and minor (skin bleeding or contusion) bleeding after acupuncture RESULTS: We included the records of 13,447,563 acupuncture sessions in 821,946 participants and followed up the patients for 14 days after each session. The incidence of minor bleeding was 8.31 per 10,000 needles, whereas that of major bleeding was 4.26 per 100,000 needles. Anticoagulants significantly increased the risk of minor bleeding (adjusted OR = 1.15 (1.03-1.28)), but the risk of major bleeding did not reach statistical significance (adjusted OR = 1.18 (0.8 0-1.75)). Anticoagulants, such as warfarin (adjusted OR = 4.95 (2.55-7.64)), direct oral anticoagulants (adjusted OR = 3.07 (1.23-5.47)), and heparin (adjusted OR = 3.72 (2.18-6.34)) significantly increased the risk of bleeding. However, antiplatelet drug was not significantly associated with post-acupuncture bleeding. Comorbidities including liver cirrhosis, diabetes, and coagulation defects, were the risk factors for bleeding after acupuncture. CONCLUSIONS: Anticoagulant drugs may increase the risk of bleeding after acupuncture. We encourage physicians to ask patients in detail about their medical history and drug use prior to acupuncture treatment.

Diagnostic test accuracy of artificial intelligence-based imaging for lung cancer screening: A systematic review and meta-analysis.

BACKGROUND: Lung cancer is the principal cause of cancer-related deaths worldwide. Early detection of lung cancer with screening is indispensable to reduce the high morbidity and mortality rates. Artificial intelligence (AI) is widely utilised in healthcare, including in the assessment of medical images. A growing number of reviews studied the application of AI in lung cancer screening, but no overarching meta-analysis has examined the diagnostic test accuracy (DTA) of AI-based imaging for lung cancer screening. OBJECTIVE: To systematically review the DTA of AI-based imaging for lung cancer screening. METHODS: PubMed, EMBASE, Cochrane Library, CINAHL, IEEE Xplore, Web of Science, ACM Digital Library, Scopus, PsycINFO, and ProQuest Dissertations and Theses were searched from inception to date. Studies that were published in English and that evaluated the performance of AI-based imaging for lung cancer screening were included. Two independent reviewers screened titles and abstracts and used the Quality Assessment of Diagnostic Accuracy Studies-2 tool to appraise the quality of selected studies. Grading of Recommendations Assessment, Development, and Evaluation to diagnostic tests was used to assess the certainty of evidence. RESULTS: Twenty-six studies with 150,721 imaging data were included. Hierarchical summary receiver-operating characteristic model used for meta-analysis demonstrated that the pooled sensitivity for AI-based imaging for lung cancer screening was 94.6 % (95 % CI: 91.4 % to 96.7 %) and specificity was 93.6 % (95 % CI: 88.5 % to 96.6 %). Subgroup analyses revealed that similar results were found among different types of AI, region, data source, and year of publication, but the overall quality of evidence was very low. CONCLUSION: AI-based imaging could effectively detect lung cancer and be incorporated into lung cancer screening programs. Further high-quality DTA studies on large lung cancer screening populations are required to validate AI's role in early lung cancer detection.

Experimental Observation of Isolative Efficacy of a Solid Coupling Medium in Extracorporeal Shock Wave Lithotripsy-Implications to Nosocomial Infection Prevention.

Introduction: Extracorporeal shock wave lithotripsy (ESWL) is a well-established, popular treatment choice for renal stones. Traditionally, the semi-liquid gel is used as a coupling medium in ESWL. During ESWL, body fluid or blood might transmit between the patients when the probe or gel used in the procedure is contaminated and cause potential nosocomial infections. To solve this problem, we developed a solid coupling medium (isolation coupling pad, referred to as "icPad") between the patient's skin and the probe as a shock wave transmission medium to prevent contamination. This study aimed to investigate the isolative efficacy of the icPad in blocking the permeation of microbes. Method: Rhodamine 6G (a fluorescent dye) was used as a tracer to simulate the microorganisms. The penetration of the fluorescent dye on the longitudinal section of the icPad was observed by a microscope after the dye was placed on the body side of the icPad for 40 min. After the shock wave, icPad was extracted with 75% ethanol, and fluorescence intensity was measured with a fluorescence spectrometer. Results: Our results revealed that the body side of icPad is free of fluorescent dye during lithotripsy. Qualitative analysis results confirmed that icPad has an isolative effect on simulating contaminants such as bacteria or viruses. Conclusion: In this in vitro phantom study, a proprietary icPad can be an isolative coupling medium and is speculated to avoid cross-contamination of bacterial or viral infection during ESWL.

Glycosylation and S-palmitoylation regulate SARS-CoV-2 spike protein intracellular trafficking.

Post-translational modifications (PTMs), such as glycosylation and palmitoylation, are critical to protein folding, stability, intracellular trafficking, and function. Understanding regulation of PTMs of SARS-CoV-2 spike (S) protein could help the therapeutic drug design. Herein, the VSV vector was used to produce SARS-CoV-2 S pseudoviruses to examine the roles of the 611LYQD614 and cysteine-rich motifs in S protein maturation and virus infectivity. Our results show that 611LY612 mutation alters S protein intracellular trafficking and reduces cell surface expression level. It also changes S protein glycosylation pattern and decreases pseudovirus infectivity. The S protein contains four cysteine-rich clusters with clusters I and II as the main palmitoylation sites. Mutations of clusters I and II disrupt S protein trafficking from ER-to-Golgi, suppress pseudovirus production, and reduce spike-mediated membrane fusion activity. Taken together, glycosylation and palmitoylation orchestrate the S protein maturation processing and are critical for S protein-mediated membrane fusion and infection.

[The Effectiveness of Acupressure in Reducing Cancer-Related Fatigue: A Systematic Review and Meta-Analysis].

BACKGROUND: Acupressure is one of the recommended non-pharmacologic treatments for cancer-related fatigue (CRF) according to the National Comprehensive Cancer Network guidelines. However, few systematic review or meta-analysis studies have focused on the effect of acupressure on CRF. PURPOSE: The purpose of this study was to examine the effectiveness of acupressure in reducing CRF and to identify the effective acupoints and frequencies of acupressure treatments. METHODS: The search and screening procedures were conducted in accordance with PRISMA 2009 guidelines. The search database included Embase, CINAHL, Cochrane Library, MEDLINE and Google Scholar. RoB 2.0 and ROBINS-I were used as appraisal tools. The statistical analysis, including effect size estimation, was computed using RevMan 5.4. RESULTS: Twelve studies (15 sets of data) were included in the review and analysis. Nine hundred sixty patients with cancer who were currently undergoing or had completed treatment were enrolled as participants and received different levels of acupressure. The result showed the overall effect size of CRF in reducing acupressure to be SMD= -0.77, 95% CI [-0.90, -0.65]. In the subgroup analysis, the effect size of auricular acupressure was SMD= -0.98, 95% CI [-1.25, -0.71] and the body acupressure effect size was SMD= -0.70, 95% CI [-0.84, -0.56]. CONCLUSIONS / IMPLICATIONS FOR PRACTICE: Based on the results of this systematic review, acupressure may be applied to the body acupoints Hegu (LI4), Zusanli (ST36), and Sanyinjiao (SP6) once daily for 1-3 minutes each and to the auricular acupoints shenmen and subcortex once daily for 3 minutes each to effectively reduce cancer-related fatigue.

Cryo-EM structures of the human GATOR1-Rag-Ragulator complex reveal a spatial-constraint regulated GAP mechanism.

mTORC1 controls cellular metabolic processes in response to nutrient availability. Amino acid signals are transmitted to mTORC1 through the Rag GTPases, which are localized on the lysosomal surface by the Ragulator complex. The Rag GTPases receive amino acid signals from multiple upstream regulators. One negative regulator, GATOR1, is a GTPase activating protein (GAP) for RagA. GATOR1 binds to the Rag GTPases via two modes: an inhibitory mode and a GAP mode. How these two binding interactions coordinate to process amino acid signals is unknown. Here, we resolved three cryo-EM structural models of the GATOR1-Rag-Ragulator complex, with the Rag-Ragulator subcomplex occupying the inhibitory site, the GAP site, and both binding sites simultaneously. When the Rag GTPases bind to GATOR1 at the GAP site, both Rag subunits contact GATOR1 to coordinate their nucleotide loading states. These results reveal a potential GAP mechanism of GATOR1 during the mTORC1 inactivation process.

Empowerment of frail institutionalized older people for self-care: from administrators' and staff caregivers' perspectives.

PURPOSE: To investigate the perspectives of administrators and staff caregivers in empowering older people living in long-term care facilities to improve self-care abilities. METHODS: A phenomenology research design was employed to generate data. The purposive sampling method was used to recruit administrator (n = 7) and staff caregiver groups (n =11). Data were collected via face-to-face interviews, observations, and daily recording. The data were then analyzed via content analysis. RESULTS: The results showed that two elements were of critical importance: professional supports and teamwork. The following professional supports activities were found of positive impacts: allowing residents to perform self-care and improving their mood status. The teamwork was developed via a partnership between staff and family caregivers, and preventing and resolving conflicts in the workplace. CONCLUSION: The teamwork could not only reduce the burdens of both staff and family caregivers, but also improve the quality of life and the capacity of older residents. Thus, residents, staffs and family caregivers should work as a team and support older people to perform self-care.

Enhancing the Prefusion Conformational Stability of SARS-CoV-2 Spike Protein Through Structure-Guided Design.

The worldwide pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is unprecedented and the impact on public health and the global economy continues to be devastating. Although early therapies such as prophylactic antibodies and vaccines show great promise, there are concerns about the long-term efficacy and universal applicability of these therapies as the virus continues to mutate. Thus, protein-based immunogens that can quickly respond to viral changes remain of continued interest. The Spike protein, the main immunogen of this virus, displays a highly dynamic trimeric structure that presents a challenge for therapeutic development. Here, guided by the structure of the Spike trimer, we rationally design new Spike constructs that show a uniquely high stability profile while simultaneously remaining locked into the immunogen-desirable prefusion state. Furthermore, our approach emphasizes the relationship between the highly conserved S2 region and structurally dynamic Receptor Binding Domains (RBD) to enable vaccine development as well as the generation of antibodies able to resist viral mutation.

Whether to transfer mosaic embryos: a cytogenetic view of true mosaicism by amniocentesis.

RESEARCH QUESTION: Preimplantation genetic testing for aneuploidies has increasingly been employed for embryo selection, resulting in a recent surge in mosaic embryos. According to the cytogenetic results, which types of mosaic embryo survive early pregnancy, progress to the second trimester and finally result in a live birth? DESIGN: This study evaluated 30,587 pregnant women undergoing amniocentesis from January 2004 to March 2020 at the cytogenic centre of Kaohsiung Chang Gung Memorial Hospital. Samples from amniocentesis were cultured using the in-situ method. The types and distribution of level III chromosomal mosaicism (two or more cells with the same abnormality in two or more colonies and both culture dishes, clinically referred to as 'true mosaicism') were retrospectively reviewed. RESULTS: Among the 30,587 women, 78 cases (0.26%) of level III chromosomal mosaicism were identified. The types of chromosomal mosaicism were classified as sex chromosome mosaicism (SCM), autosomal chromosome mosaicism (ACM) and marker chromosome mosaicism (MCM), with SCM, ACM and MCM accounting for 58.97%, 32.05% and 8.97% of cases, respectively. The most common mosaic cell lines were monosomy X and trisomy 21. The most common mosaic cell line progressing to live birth was monosomy X. CONCLUSIONS: Mosaic monosomy X and trisomy 21 are the most common cell lines of true mosaicism determined by amniocentesis. Monosomy X mosaicism is the most common cell line in live births. For women considering the transfer of these types of mosaic embryo in a circumstance where euploid embryos are unavailable, clinicians should provide careful prenatal counselling, detailed ultrasonography and amniocentesis.

The dynamics of patient visits to traditional Chinese medicine during the 2019 coronavirus pandemic.

BACKGROUND: Large-scale epidemics have changed people's medical behavior, and patients tend to delay non-urgent medical needs. However, the impact of the pandemic on the use of complementary and alternative medicine remains unknown. METHODS: This retrospective study aimed to analyze the changes in the number of traditional Chinese medicine (TCM) patients and examine the epidemic prevention policy during the coronavirus disease 2019 (COVID-19) pandemic. We analyzed the number of TCM patients in Taipei City Hospital from January 2017 to May 2020. We tallied the numbers of patients in each month and compared them with those in the same months last year. We calculated the percentage difference in the number of patients to reveal the impact of the COVID-19 pandemic on TCM utilization. We used the Mann-Whitney U test to examine whether there was a significant difference in the number of patients during the COVID-19 pandemic. RESULTS: We included a total of 1,935,827 TCM visits of patients from January 2017 to May 2020 in this study. During the COVID-19 pandemic, the number of patients decreased significantly, except in February 2020. The number of patients during the COVID-19 pandemic had fallen by more than 15% compared with those in the same months last year. March and April had the greatest number of patient losses, with falls of 32.8 and 40% respectively. TCM patients declined significantly during the COVID-19 pandemic, and mobile medicine provided to rural areas fell considerably. Among all the TCM specialties, pediatrics and traumatology, as well as infertility treatment, witnessed the most significant decline in the number of patients. However, the number of cancer patients has reportedly increased. CONCLUSIONS: The COVID-19 pandemic decreased the utilization rate of TCM, especially for mobile healthcare in rural areas. We suggest that the government pay attention to the medical disparity between urban and rural areas, which are affected by the pandemic, as well as allocate adequate resources in areas deprived of medical care.

A multigroup analysis of factors underlying teachers' technostress and their continuance intention toward online teaching.

Online teaching has been implemented in response to the COVID-19 pandemic. Nonetheless, teaching online consumes considerable time and adds pressure to teachers' daily lives. Teachers have to not only acquire technical skills but also provide engaging instruction online. Meanwhile, privacy breaches occasionally occur in online teaching. The objective of the current study is to analyze the factors underlying the continuance intention toward online teaching beyond the COVID-19 pandemic. We use the person-environment fit theory to develop the survey for investigation. An open-ended question appended to the survey helps to gather teachers' further thoughts on sustainable online teaching. The structural equation modeling reveals that teachers' technostress is associated with their privacy concerns and self-efficacy in delivering effective instruction amid online teaching. The multigroup analysis further demonstrates that technostress, self-efficacy and school support are related to the continuance intention to teach online for teachers at distinct teaching levels to different extents. The responses to the open-ended question reveal that teachers' preference for online instruction lies in wealthy teaching resources and flexibility. Students' learning performance and the effectiveness of assessments constitute a concern in conducting online teaching. The implications for policymakers and teachers are remarked upon at the end of this paper.

The structural basis of Rubisco phase separation in the pyrenoid.

Approximately one-third of global CO2 fixation occurs in a phase-separated algal organelle called the pyrenoid. The existing data suggest that the pyrenoid forms by the phase separation of the CO2-fixing enzyme Rubisco with a linker protein; however, the molecular interactions underlying this phase separation remain unknown. Here we present the structural basis of the interactions between Rubisco and its intrinsically disordered linker protein Essential Pyrenoid Component 1 (EPYC1) in the model alga Chlamydomonas reinhardtii. We find that EPYC1 consists of five evenly spaced Rubisco-binding regions that share sequence similarity. Single-particle cryo-electron microscopy of these regions in complex with Rubisco indicates that each Rubisco holoenzyme has eight binding sites for EPYC1, one on each Rubisco small subunit. Interface mutations disrupt binding, phase separation and pyrenoid formation. Cryo-electron tomography supports a model in which EPYC1 and Rubisco form a codependent multivalent network of specific low-affinity bonds, giving the matrix liquid-like properties. Our results advance the structural and functional understanding of the phase separation underlying the pyrenoid, an organelle that plays a fundamental role in the global carbon cycle.

Geometric Effect on the Nonlinear Force-Displacement Relationship of Awl-Shaped Serpentine Microsprings for In-Plane Deformation.

Even when made by brittle materials, awl-shaped serpentine microsprings (ASSMs) were found to have a nonlinear displacement-force relationship similar to springs made by ductile material. It is found that the nonlinear displacement-force relationship is due to the geometry and dimensions of the ASSMs. The geometric effect of the nonlinear force-displacement relationship of ASSMs for in-plane motion was investigated. A theoretical solution was derived to analyze this nonlinearity. By successfully fabricating and measuring an ASSM, the theoretical results agreed well with the experimental results. The results indicated that ASSMs have a nonlinear force-displacement relationship, which is similar to that of hardening springs. The taper angle has a significant effect on the nonlinear displacement of ASSMs. When the taper angle was small, no obvious effect appeared on the nonlinearity of the microsprings with different numbers of turns. When the beam length increased, the critical force for nonlinear deflection decreased.

Near-atomic structures of the BBSome reveal the basis for BBSome activation and binding to GPCR cargoes.

Dynamic trafficking of G protein-coupled receptors (GPCRs) out of cilia is mediated by the BBSome. In concert with its membrane recruitment factor, the small GTPase ARL6/BBS3, the BBSome ferries GPCRs across the transition zone, a diffusion barrier at the base of cilia. Here, we present the near-atomic structures of the BBSome by itself and in complex with ARL6GTP, and we describe the changes in BBSome conformation induced by ARL6GTP binding. Modeling the interactions of the BBSome with membranes and the GPCR Smoothened (SMO) reveals that SMO, and likely also other GPCR cargoes, must release their amphipathic helix 8 from the membrane to be recognized by the BBSome.