Hemagglutinin and neuraminidase of a non-pathogenic H7N7 avian influenza virus coevolved during the acquisition of intranasal pathogenicity in chickens.

Polybasic amino acid residues at the hemagglutinin (HA) cleavage site are insufficient to induce the highly pathogenic phenotype of avian influenza viruses in chickens. In our previous study, an H7N7 avian influenza virus named "Vac2sub-P0", which is nonpathogenic despite carrying polybasic amino acids at the HA cleavage site, was passaged in chick air sacs, and a virus with high intravenous pathogenicity, Vac2sub-P3, was obtained. Intranasal infection with Vac2sub-P3 resulted in limited lethality in chickens; therefore, in this study, this virus was further passaged in chicken lungs, and the resultant virus, Vac2sub-P3L4, acquired high intranasal pathogenicity. Experimental infection of chickens with recombinant viruses demonstrated that mutations in HA and neuraminidase (NA) found in consecutive passages were responsible for the increased pathogenicity. The HA and NA functions of Vac2sub-P3L4 were compared with those of the parental virus in vitro; the virus growth at 40 °C was faster, the binding affinity to a sialic acid receptor was lower, and the rate of release by NA from the cell surface was lower, suggesting that these changes enabled the virus to replicate efficiently in chickens with high intranasal pathogenicity. This study demonstrates that viruses that are highly pathogenic when administered intranasally require additional adaptations for increased pathogenicity to be highly lethal to intranasally infected chickens.

Effects of probiotics on sleep parameters: A systematic review and meta-analysis.

AIM: Although sleep is essential for maintaining good health and well-being, sleep disorders are becoming increasingly prevalent. Probiotics may play a role in sleep regulation; therefore, this study aimed to provide a comprehensive overview of the effects of probiotics on sleep parameters. METHODS: We conducted a systematic literature review and meta-analysis, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology. Relevant placebo-controlled randomized controlled trials examining the effects of probiotics on sleep outcomes were identified through systematic searches in the PubMed, Cochrane Library, and Ichushi databases. Data were extracted from eligible studies and the risk of bias was assessed. Statistical analyses were performed to assess the effects of probiotics on various sleep-related variables. RESULTS: Fifteen randomized controlled trials were included in this review. The decrease in Pittsburgh Sleep Quality Index (PSQI) scores in the probiotics group was significantly lower than that in the placebo group after 4-6 weeks and 8-16 weeks, indicating improved sleep quality. The Oguri-Shirakawa-Azumi (OSA) sleep inventory score was also decreased in the probiotics group for Factor 1 "sleepiness on rising" and Factor 4 "refreshing," indicating improved sleep quality. Some studies however, showed a risk of bias. CONCLUSION: This systematic review and meta-analysis indicated that probiotics may improve sleep quality, as measured by the PSQI and OSA sleep inventory. However, further research is needed to better understand the effects of probiotics on specific sleep parameters and address the limitations of existing studies.

Adverse Events Comparison of Double Beta-Lactam Combinations for Bloodstream Infections: Ampicillin plus Ceftriaxone and Ampicillin/Cloxacillin.

In Japan, only ampicillin/cloxacillin (ABPC/MCIPC) is available as an anti-staphylococcal penicillin-based treatment for Staphylococcus aureus bacteremia. However, the incidence of adverse events associated with double beta-lactam administration remains unknown. Therefore, we investigated the adverse events of double beta-lactam administration in patients with bacteremia. Adult patients (≥18 years) with bacteremia treated with ABPC, ABPC + ceftriaxone (CTRX), or ABPC/MCIPC were retrospectively analyzed. The primary outcome of this study was the incidence of adverse events such as acute kidney injury, liver dysfunction, and myelosuppression. Chi-square tests and t-tests were used for bivariate analysis. Propensity score (PS) matching was conducted to adjust for confounding factors. We included 277 ABPC-, 57 ABPC + CTRX-, and 43 ABPC/MCIPC-treated patients. Significant differences were noted in age, number of male patients, proportion of patients with qSOFA score ≥2, incidence of chronic kidney disease, treatment duration, mechanical ventilation use, vasopressor use, and proportion of patients with acute kidney injury (AKI) KDIGO grade ≥2. Further, a significant difference was observed between ABPC and ABPC/MCIPC, with a hazard ratio of 1.83 in AKI. In the PS-matched cohort, AKI incidence associated with ABPC/MCIPC was significantly higher than that associated with ABPC. ABPC + CTRX may be safe, whereas ABPC/MCIPC presents a higher risk of AKI and may not be suitable.

A Case of Idiopathic Multicentric Castleman's Disease Diagnosed From Anemia and Renal Dysfunction on an Annual Check-Up.

A 34-year-old man was referred to our hospital because of mild renal dysfunction and anemia. He had no specific preexisting medical conditions; his complaint was fatigue. Physical examination revealed several mobile, pinky head-sized (no tenderness) palpable lymph nodes on the bilateral neck. Blood biochemistry tests revealed anemia, renal dysfunction, increased inflammation, and a protein-albumin discrepancy. Immunological examination revealed polyclonal elevation of immunoglobulins (no shift in κ/λ ratio). A cervical lymph node biopsy was performed, and the pathological results showed numerous clusters of mature plasma cells (plasmacytic type), leading to the definitive diagnosis of idiopathic multicentric Castleman's disease (iMCD).

A blurring correction method suitable to analyze quantitative x-ray images derived from energy-resolving photon counting detector.

Objective.The purpose of this study is to propose a novel blurring correction method that enables accurate quantitative analysis of the object edge when using energy-resolving photon counting detectors (ERPCDs). Although the ERPCDs have the ability to generate various quantitative analysis techniques, such as the derivations of effective atomic number (Zeff) and bone mineral density values, at the object edge in these quantitative images, accurate quantitative information cannot be obtained. This is because image blurring prevents the gathering of accurate primary x-ray attenuation information.Approach.We developed the following procedure for blurring correction. A 5 × 5 pixels masking region was set as the processing area, and the pixels affected by blurring were extracted from the analysis of pixel value distribution. The blurred pixel values were then corrected to the proper values estimated by analyzing minimum and/or maximum values in the set mask area. The suitability of our correction method was verified by a simulation study and an experiment using a prototype ERPCD.Main results. WhenZeffimage of aluminum objects (Zeff= 13) were analyzed without applying our correction method, regardless of raw data or correction data applying a conventional edge enhancement method, the properZeffvalues could not be derived for the object edge. In contrast, when applying our correction method, 82% of pixels affected by blurring were corrected and the properZeffvalues were calculated for those pixels. As a result of investigating the applicability limits of our method through simulation, it was proven that it works effectively for objects with 4 × 4 pixels or more.Significance. Our method is effective in correcting image blurring when the quantitative image is calculated based on multiple images. It will become an in-demand technology for putting a quantitative diagnosis into actual medical examinations.

Chondroitin sulfate modification of CSPG4 regulates the maintenance and differentiation of glioma-initiating cells via integrin-associated signaling.

Glioma stem cell/glioma-initiating cell (GIC) and their niches are considered responsible for the therapeutic resistance and recurrence of malignant glioma. To clarify the molecular mechanisms of GIC maintenance/differentiation, we performed a unique integrated proteogenomics utilizing GIC clones established from patient tumors having the potential to develop glioblastoma. After the integration and extraction of the transcriptomics/proteomics data, we found that chondroitin sulfate proteoglycan 4 (CSPG4) and its glycobiosynthetic enzymes were significantly upregulated in GICs. Glyco-quantitative PCR array revealed that chondroitin sulfate (CS) biosynthetic enzymes, such as xylosyltransferase 1 (XYLT1) and carbohydrate sulfotransferase 11, were significantly downregulated during serum-induced GIC differentiation. Simultaneously, the CS modification on CSPG4 was characteristically decreased during the differentiation and also downregulated by XYLT1 knockdown. Notably, the CS degradation on CSPG4 by ChondroitinaseABC treatment dramatically induced GIC differentiation, which was significantly inhibited by the addition of CS. GIC growth and differentiation ability were significantly suppressed by CSPG4 knockdown, suggesting that CS-CSPG4 is an important factor in GIC maintenance/differentiation. To understand the molecular function of CS-CSPG4, we analyzed its associating proteins in GICs and found that CSPG4, but not CS-CSPG4, interacts with integrin αV during GIC differentiation. This event sequentially upregulates integrin-extracellular signal-regulated kinase signaling, which can be inhibited by cyclic-RGD (Arg-Gly-Asp) integrin αV inhibitor. These results indicate that CS-CSPG4 regulates the GIC microenvironment for GIC maintenance/differentiation via the CS moiety, which controls integrin signaling. This study demonstrates a novel function of CS on CSPG4 as a niche factor, so-called "glyco-niche" for GICs, and suggests that CS-CSPG4 could be a potential target for malignant glioma.

Early mortality of emergency surgery for acute type A aortic dissection in octogenarians and nonagenarians: A multi-center retrospective study.

OBJECTIVES: The clinical data on postoperative mortality and central nervous system (CNS) complications in older adults who underwent acute type A aortic dissection are limited. Thus, in this study we aimed to evaluate the association between age and early postoperative mortality and occurrence of CNS complications. METHODS: This multicentric retrospective cohort study included 5 tertiary hospitals in Japan. All patients who underwent emergency surgery for acute type A aortic dissection between October 1998 and December 2019 were enrolled. The multilevel Cox proportional hazards model, which considered years as level 1, institutions as level 2, and surgeons as level 3, was used to evaluate the association between age and early postoperative hospital mortality and occurrence of CNS complications. RESULTS: Of the 1037 patients, 227 (21.9%) were ≥80 years old and 810 (78.1%) were <80 years old. Overall, 134 patients (12.9%) died within 30 days postoperatively; among them, 42/227 (18.5%) and 92/810 (11.4%) were aged ≥80 and <80 years, respectively (hazard ratio [HR], 1.63; P = .0046). CNS complications within 30 days postoperatively occurred in 140/1037 (13.5%) patients; among them, 42/227 (18.5%) and 98/810 (12.1%) were aged ≥80 and <80 years, respectively (HR, 1.63; P = .011). In multivariate analysis, age ≥80 years was associated with mortality within 30 days postoperatively (adjusted HR, 2.37; 95% CI, 1.23-4.57; P = .01) but not with CNS complications (adjusted HR, 1.58; 95% CI, 0.93-2.69; P = .091). CONCLUSIONS: The early postoperative mortality in older patients was approximately 50% higher than in the younger population. A thorough discussion regarding the surgical indications should be done.

Performance of elastic x-ray shield made by embedding Bi2 O3 particles in porous polyurethane.

BACKGROUND: Many healthcare institutions have guidelines concerning the usage of protective procedures, and various x-ray shields have been used to reduce unwanted radiation exposure to medical staff and patients when using x-rays. Most x-ray shields are in the form of sheets and lack elasticity, which limits their effectiveness in shielding areas with movement, such as the thyroid. To overcome this limitation, we have developed an innovative elastic x-ray shield. PURPOSE: The purpose of this study is to explain the methodology for developing and evaluating a novel elastic x-ray shield with sufficient x-ray shielding ability. Furthermore, valuable knowledge and evaluation indices are derived to assess our shield's performance. METHODS: Our x-ray shield was developed through a process of embedding Bi2 O3 particles into porous polyurethane. Porous polyurethane with a thickness of 10 mm was dipped into a solution of water, metal particles, and chemical agents. Then, it was air-dried to fix the metal particles in the porous polyurethane. Thirteen investigational x-ray shields were fabricated, in which Bi2 O3 particles at various mass thicknesses (ranging from 585 to 2493 g/m2 ) were embedded. To determine the performance of the shielding material, three criteria were evaluated: (1) Dose Reduction Factor ( D R F $DRF$ ), measured using inverse broad beam geometry; (2) uniformity, evaluated from the standard deviation ( S D $SD$ ) of the x-ray image obtained using a clinical x-ray imaging detector; and (3) elasticity, evaluated by a compression test. RESULTS: The elastic shield with small pores, containing 1200 g/m2 of the metal element (Bi), exhibited a well-balanced performance. The D R F $DRF$ was approximately 80% for 70 kV diagnostic x-rays. This shield's elasticity was -0.62 N/mm, a loss of only 30% when compared to porous polyurethane without metal. Although the non-uniformity of the x-ray shield leads to poor shielding ability, it was found that the decrease in the shielding ability can be limited to a maximum of 6% when the shield is manufactured so that the S D $SD$ of the x-ray image of the shield is less than 10%. CONCLUSIONS: It was verified that an elastic x-ray shield that offers an appropriate reduction in radiation exposure can be produced by embedding Bi2 O3 particles into porous polyurethane. Our findings can lead to the development of novel x-ray shielding products that can reduce the physical and mental stress on users.

Predictive Rule for Mortality of Inpatients With Escherichia coli Bacteremia: Chi-Square Automatic Interaction Detector Decision Tree Analysis Model.

AIM: A predictive rule for risk factors for mortality due to Escherichia coli (E. coli)bacteremia has not been defined, especially using the chi-square automatic interaction detector (CHAID) decision tree analysis. Here we aimed to create the predictive rule for risk factors for in-hospital mortality due to E. coli bacteremia. METHODS: The outcome of this retrospective cross-sectional survey was death in the hospital due to E. coli bacteremia. Factors potentially predictive of death in the hospital due to E. coli bacteremia were analyzed using the CHAID decision tree analysis. RESULTS: A total of 420 patients (male:female=196:224; mean±standard deviation [SD] age, 75.81±13.13 years) were included in this study. 56 patients (13.3%) died in the hospital. The CHAID decision tree analysis revealed that patients with total protein level ≤5.10 g/dL (incidence, 46.2%), total protein level ≤5.90 g/dL with disturbance of consciousness (incidence, 39.4%), and total protein level >5.90 g/dL with hemoglobin level ≤11.10 g/dL and lactate dehydrogenase level ≥312.0 IU/L (incidence, 42.3%) were included in the high-risk group. CONCLUSIONS: Appropriate preventative therapy should be facilitated in patients with E. coliat a high risk of mortality.

Association of illness perception and alexithymia with fatigue in hemodialysis recipients: a single-center, cross-sectional study.

Fatigue in hemodialysis recipients interferes with daily activities and renal rehabilitation, and its underlying causes and treatment remain unclear. Psychological factors, like illness perceptions and alexithymia, cause fatigue in other diseases; however, their contribution to hemodialysis-related fatigue is unknown. This cross-sectional study included 53 hemodialysis recipients. To assess participants' fatigue, we used a self-administered patient-reported outcome questionnaire whose items have shown correlation with those of established scales, such as the Profile of Mood States and Visual Analogue Scales. The associations among the scores of the revised Illness Perceptions Questionnaire (IPQ-R), Toronto Alexithymia Scale (TAS-20), and Hospital Anxiety and Depression Scale and fatigue were analyzed using bivariable and multivariable analyses. Patients with fatigue had significantly higher median scores for the IPQ-R subscales "Identity" and "Negative emotional representation about illness" than those without fatigue, suggesting the association of specific illness perception with fatigue. Median scores for the TAS-20 subscale "Difficulty identifying feelings" were also significantly higher among fatigued patients, suggesting the association of alexithymia with fatigue. Depression was not associated with fatigue. Multivariable logistic regression revealed the association of a high "Identity" score with the risk of fatigue (adjusted odds ratio, 1.32; 95% confidence interval, 1.00-1.73; P = 0.04), while there were no significant association between a high "Difficulty identifying feelings" score and the risk of fatigue (adjusted odds ratio, 1.09; 95% confidence interval, 0.95-1.24). Specific illness perception and alexithymia were slightly associated with hemodialysis-related fatigue. Cognitive-behavioral therapy for these conditions could reduce fatigue and promote renal rehabilitation.

Usefulness of the GLIM criteria to predict recovery of activities of daily living in older adults with post-acute stroke.

OBJECTIVES: The usefulness of malnutrition diagnosed using the Global Leadership Initiative on Malnutrition (GLIM) criteria as a predictor of recovery of activities of daily living is unclear. This study aimed to investigate whether baseline malnutrition diagnosed using the GLIM criteria was predictive of recovery of activities of daily living in older patients with post-acute stroke. MATERIALS AND METHODS: A retrospective cohort study was conducted in patients aged ≥70 years with post-acute stroke. The outcome was activities of daily living measured using the motor domain of the Functional Independence Measure (FIM-motor) score at discharge. Participants were classified as malnourished or non-malnourished according to the GLIM criteria. Multivariate linear regression analyses were performed to determine whether baseline malnutrition diagnosed using the GLIM criteria was predictive of the FIM-motor score at discharge. The analysis was adjusted for clinically relevant covariates associated with rehabilitation outcomes after stroke. RESULTS: A total of 236 patients (mean age, 80.0 years; female, 54.2%) were included in the analysis. On admission, 83 (35.2%) patients were diagnosed with malnutrition. Multivariate linear regression analyses showed that malnutrition diagnosed using the GLIM criteria was predictive of the FIM-motor score at discharge (ß = -0.347, P < 0.001). CONCLUSIONS: Identifying malnutrition using the GLIM criteria is useful for predicting recovery of activities of daily living in older patients with post-acute stroke.

Limited proteolysis of mycobacterial DNA-binding protein 1 with an extended, lysine-rich, intrinsically disordered region to unveil posttranslational modifications.

The basic, intrinsically disordered regions of eukaryotic histones and their bacterial counterparts are presumed to act as signaling hubs to regulate the compaction of chromosomes or nucleoids and various DNA processes such as gene expression, recombination, and DNA replication. Posttranslational modifications (PTMs) on these regions are pivotal in regulating chromosomal or nucleoid compaction and DNA processes. However, the low sequence complexity and the presence of short lysine-rich repeats in the regions have hindered the accurate determination of types and locations of PTMs using conventional proteomic procedures. We described a limited proteolysis protocol using trypsin to analyze PTMs on mycobacterial DNA-binding protein 1 (MDP1), a nucleoid-associated protein in mycobacterial species that possesses an extended, lysine-rich, intrinsically disordered region in its C-terminal domain. This limited proteolysis approach successfully revealed significant methylation on many lysine residues in the C-terminal domain of MDP1 purified from Mycobacterium tuberculosis, which was lacking in the corresponding region of recombinant MDP1 expressed in Escherichia coli.

A Predictive Rule for COVID-19 Pneumonia Among COVID-19 Patients: A Classification and Regression Tree (CART) Analysis Model.

BACKGROUND: In this study, we aimed to identify predictive factors for coronavirus disease 2019 (COVID-19) patients with complicated pneumonia and determine which COVID-19 patients should undergo computed tomography (CT) using classification and regression tree (CART) analysis. METHODS: This retrospective cross-sectional survey was conducted at a university hospital. We recruited patients diagnosed with COVID-19 between January 1 and December 31, 2020. We extracted clinical information (e.g., vital signs, symptoms, laboratory results, and CT findings) from patient records. Factors potentially predicting COVID-19 pneumonia were analyzed using Student's t-test, the chi-square test, and a CART analysis model. RESULTS: Among 221 patients (119 men (53.8%); mean age, 54.59±18.61 years), 160 (72.4%) had pneumonia. The CART analysis revealed that patients were at high risk of pneumonia if they had C-reactive protein (CRP) levels of >1.60 mg/dL (incidence of pneumonia: 95.7%); CRP levels of ≤1.60 mg/dL + age >35.5 years + lactate dehydrogenase (LDH)>225.5 IU/L (incidence of pneumonia: 95.5%); and CRP levels of ≤1.60 mg/dL + age >35.5 years + LDH≤225.5 IU/L + hemoglobin ≤14.65 g/dL (incidence of pneumonia: 69.6%). The area of the curve of the receiver operating characteristic of the model was 0.860 (95% CI: 0.804-0.915), indicating sufficient explanatory power. CONCLUSIONS: The present results are useful for deciding whether to perform CT in COVID-19 patients. High-risk patients such as those mentioned above should undergo CT.

Association of Low-Normal Free T4 Levels With Future Major Depression Development.

Context: Hyperthyroidism and overt and subclinical hypothyroidism are associated with major depression; however, the association of major depression across the spectrum of thyroid function within the normal range is unknown. Objective: We investigated whether higher or lower levels of free thyroxine (T4) and thyrotropin (TSH) within the normal range are associated with major depression. Methods: This was a retrospective cohort study of 66 960 participants with normal thyroid function who visited for health checkups (St. Luke's International Hospital, 2005-2018). The primary outcome was the development of major depression during the follow-up period. Participants were divided into 3 equal groups based on baseline free T4 or TSH values (low-, middle-, or high-normal), and the incidence of major depression was compared using the Cox proportional hazard model after adjusting for potential covariates. Results: During the median follow-up of 1883 days, 1363 (2.0%) patients developed major depression. The low-normal free T4 group had a significantly higher risk of major depression (adjusted HR 1.15; 95% CI, 1.01-1.31), but not the high-normal free T4 group or TSH groups. The association between low-normal free T4 and the development of major depression was maintained, rather more obvious, upon exclusion of participants whose thyroid hormone levels became abnormal during follow-up compared with data from all participants (adjusted HR 1.24; 95% CI, 1.07-1.43). Conclusion: In this cohort, low-normal free T4 was associated with an increased risk of future major depression, even if subsequent hormone levels were maintained within the normal range. The magnitude of the impact of low-normal free T4 was relatively mild.

Effect of Medical Fee Schedule Revisions on the Expansion of Nutritional Support Teams in Japan: An Interrupted Time-series Analysis.

Introduction: In 2018, the fee schedule for nutrition support teams (NSTs) in Japanese hospitals was changed. The change was intended to encourage more hospitals to establish NSTs, and this study aims to investigate whether this change had the desired effect. Specifically, we will look at the proportion of hospitals with NSTs before and after the 2018 revision to see if there was a significant increase in the number of hospitals with NSTs. Methods: The study analyzed administrative data from 10 Japanese prefectures dating from June 2015 to September 2021 using an interrupted time-series design. The analysis focused on all acute care hospitals within these prefectures and measured the percentage of hospitals with NSTs. Subgroup analyses were conducted based on hospital size and functions. In April 2018, the intervention, a fee schedule revision, was implemented. Results: We analyzed 1,471 acute care hospitals. Immediately after the intervention, the percentage of hospitals with NSTs increased by 4.59% (95% CI = 3.92%, 5.26%) and by 0.66% (95% CI = 0.57%, 0.75%) quarterly thereafter. We observed a marked increase in NST formation among large-sized (20.9%), medium-sized (28.0%), and highly acute care hospitals (hospitals with emergency medical care centers and intensive care units, 22.3% and 23.6%, respectively). We also noted a moderate increase among hospitals with convalescent rehabilitation units (10.1%) and a modest increase among small-sized hospitals (6.9%). Conclusions: Relaxation of the NST fee requirement increased the proportion of hospitals with NSTs in Japan, especially among larger and highly acute care hospitals.

Bioinformatic Identification of Potential RNA Alterations on the Atrial Fibrillation Remodeling from Human Pulmonary Veins.

Atrial fibrillation (AF) is the most frequent persistent arrhythmia. Many genes have been reported as a genetic background for AF. However, most transcriptome analyses of AF are limited to the atrial samples and have not been evaluated by multiple cardiac regions. In this study, we analyzed the expression levels of protein-coding and long noncoding RNAs (lncRNAs) in six cardiac regions by RNA-seq. Samples were donated from six subjects with or without persistent AF for left atria, left atrial appendages, right atria, sinoatrial nodes, left ventricles, right ventricles, and pulmonary veins (PVs), and additional four right atrial appendages samples were collected from patients undergoing mitral valve replacement. In total, 23 AF samples were compared to 23 non-AF samples. Surprisingly, the most influenced heart region in gene expression by AF was the PV, not the atria. The ion channel-related gene set was significantly enriched upon analysis of these significant genes. In addition, some significant genes are cancer-related lncRNAs in PV in AF. A co-expression network analysis could detect the functional gene clusters. In particular, the cancer-related lncRNA, such as SAMMSON and FOXCUT, belong to the gene network with the cancer-related transcription factor FOXC1. Thus, they may also play an aggravating role in the pathogenesis of AF, similar to carcinogenesis. In the least, this study suggests that (1) RNA alteration is most intense in PVs and (2) post-transcriptional gene regulation by lncRNA may contribute to the progression of AF. Through the screening analysis across the six cardiac regions, the possibility that the PV region can play a role other than paroxysmal triggering in the pathogenesis of AF was demonstrated for the first time. Future research with an increase in the number of PV samples will lead to a novel understanding of the pathophysiology of AF.

Inverse agonism of lysophospholipids with cationic head groups at Gi-coupled receptor GPR82.

GPR82 is an orphan G protein-coupled receptor (GPCR) that has been implicated in lipid storage in mouse adipocytes. However, the intracellular signaling as well as the specific ligands of GPR82 remain unknown. GPR82 is closely related to GPR34, a GPCR for the bioactive lipid molecule lysophosphatidylserine. In this study, we screened a lipid library using GPR82-transfected cells to search for ligands that act on GPR82. By measuring cyclic adenosine monophosphate levels, we found that GPR82 is an apparently constitutively active GPCR that leads to Gi protein activation. In addition, edelfosine (1-O-octadecyl-2-O-methyl-sn-glycero-3-phosphocholine), an artificial lysophospholipid with a cationic head group that exerts antitumor activity, inhibited the Gi protein activation by GPR82. Two endogenous lysophospholipids with cationic head groups, lysophosphatidylcholine (1-oleoyl-sn-glycero-3-phosphocholine) and lysophosphatidylethanolamine (1-oleoyl-sn-glycero-3-phosphoethanolamine), also exhibited GPR82 inhibitory activity, albeit weaker than edelfosine. Förster resonance energy transfer imaging analysis consistently demonstrated that Gi protein-coupled GPR82 has an apparent constitutive activity that is edelfosine-sensitive. Consistent data were obtained from GPR82-mediated binding analysis of guanosine-5'-O-(3-thiotriphosphate) to cell membranes. Furthermore, in GPR82-transfected cells, edelfosine inhibited insulin-induced extracellular signal-regulated kinase activation, like compounds that function as inverse agonists at other GPCRs. Therefore, edelfosine is likely to act as an inverse agonist of GPR82. Finally, GPR82 expression inhibited adipocyte lipolysis, which was abrogated by edelfosine. Our findings suggested that the cationic lysophospholipids edelfosine, lysophosphatidylcholine and lysophosphatidylethanolamine are novel inverse agonists for Gi-coupled GPR82, which is apparently constitutively active, and has the potential to exert lipolytic effects through GPR82.

The role of gram stain in reducing broad-spectrum antibiotic use: A systematic literature review and meta-analysis.

The number of studies that verify whether Gram stain can help to reduce the use of broad-spectrum antibiotics is relatively limited compared to those evaluating its concordance with culture test results. Thereby, we aimed to evaluate the effectiveness of Gram staining in the reduction of broad-spectrum antibiotics and its impact on clinical outcomes. We systematically reviewed studies having used Gram stain to guide antibiotic selection and evaluated performance measures between 1996 and 2022. We extracted available data on broad-spectrum antibiotic use as a primary outcome of the studies in view of an exploratory meta-analysis designed to estimate the clinical effect of Gram stain. We also evaluated the clinical response and coverage rates of the initial antibiotic therapy. One randomized study and four non-randomized studies were eligible, all of which were conducted in tertiary care hospitals in Japan. Gram stain was associated with reduced broad-spectrum antibiotic use, including antipseudomonal antibiotics (odds ratio [OR], 0.05; 95% confidence interval [CI], 0.01-0.34), anti-methicillin-resistant Staphylococcus aureus antibiotics (OR, 0.21; 95% CI, 0.07-0.63), and carbapenems (OR, 0.07; 95% CI, 0.02-0.19), without impairing clinical outcomes, including clinical response rate (OR, 1.48; 95% CI, 0.95-2.31) and coverage rate of initial antibiotic therapy (OR, 0.70; 95% CI, 0.40-1.22) using random-effects models in our meta-analysis. In conclusion, Gram stain may be useful in guiding initial antibiotic selection without apparent adverse clinical outcomes. However, currently available studies evaluating the clinical usefulness of Gram stain are limited to specific clinical settings.

The incidence and factors of inappropriate rapid antigen test usage for group A streptococcus.

INTRODUCTION: Although rapid antigen tests (RADTs) for group A streptococcus (GAS) can help diagnose group A streptococcal pharyngitis, little is known about the inappropriate use of these RADTs. METHODS: This retrospective observational study compared the appropriate vs. inappropriate use of RADTs in patients who had a RADT between January 2019 and August 2022. RADTs for patients with a low Centor score of 0-1 point were deemed inappropriate. RESULTS: Of the 1015 patients, 380 (37.4%) had inappropriate RADTs. Patients with asthma were associated with an increased risk of inappropriate testing. In contrast, during the coronavirus 2019 pandemic, outpatients and residents were associated with a reduced risk of inappropriate testing. Consequent to the inappropriate use of RADTs, 162 (16.0%) patients received potentially inappropriate antibiotics. CONCLUSIONS: Our results suggest that diagnostic stewardship for pharyngitis, including education for healthcare workers, is needed to reduce inappropriate test ordering and prevent unnecessary care.