Construction of Diverse Pyrrolidine-Based Skeletons through the Ag-Catalyzed Stereoselective Addition-Elimination Reaction of Azomethine Ylides with Nitroallyl Acetates.

Because scaffold diversity has a pronounced impact on biological screening, the efficient and expedient construction of skeletally diverse compound collections is a fundamental demand in drug discovery. In this regard, we report here an asymmetric tandem conjugate addition-elimination reaction of pyrroline esters with nitroallyl acetates and its application to the construction of various types of fused or spirocyclic pyrrolidines. A AgOAc/(R,Sp)-ThioClickFerrophos (TCF) catalyst efficiently promotes the addition-elimination reaction, setting vicinal chiral stereocenters featuring a tetrasubstituted carbon with excellent enantio- and diastereoselectivity while leaving the versatile nitroolefin moiety. The broad substrate scope of this reaction and the transformability of the resulting nitroolefin, imine, and ester moieties allow for the construction of diverse pyrrolidine-based fused or spiro bicyclic skeletons in optically active forms by various intramolecular cyclization processes.

Antioxidants restore store-operated Ca2+ entry in patient-iPSC-derived myotubes with tubular aggregate myopathy-associated Ile484ArgfsX21 STIM1 mutation via upregulation of binding immunoglobulin protein.

Store-operated Ca2+ entry (SOCE) is indispensable for intracellular Ca2+ homeostasis in skeletal muscle, and constitutive activation of SOCE causes tubular aggregate myopathy (TAM). To understand the pathogenesis of TAM, we induced pluripotent stem cells (iPSCs) from a TAM patient with a rare mutation (c.1450_1451insGA; p. Ile484ArgfsX21) in the STIM1 gene. This frameshift mutation produces a truncated STIM1 with a disrupted C-terminal inhibitory domain (CTID) and was reported to diminish SOCE. Myotubes induced from the patient's-iPSCs (TAM myotubes) showed severely impaired SOCE, but antioxidants greatly restored SOCE partly via upregulation of an endoplasmic reticulum (ER) chaperone, BiP (GRP78), in the TAM myotubes. Our observation suggests that antioxidants are promising tools for treatment of TAM caused by reduced SOCE.

Detection of parechovirus-A in hospitalized children with acute lower respiratory infection in Myanmar, 2017-2018.

Parechovirus-A (PeV-A) causes emerging infection in children, and clinical presentation depends on genotype. The virus has been investigated mainly in developed countries; however, data from developing countries, especially in Asia, are sparse. This study investigated whether PeV-A circulated in children in Myanmar. This retrospective study evaluated PeV-A in nasopharyngeal samples from children aged 1 month to 12 years who were hospitalized with acute lower respiratory infection at Yankin Children Hospital, Yangon, Myanmar, during the period from May 2017 to April 2019. Real-time polymerase chain reaction (PCR) was used to detect PeV-A, and PCR-positive samples were used for genotyping and phylogenetic analysis. In total, 11/570 (1.9%) of samples were positive for PeV-A; 7 were successfully genotyped by sequencing the VP3/VP1 region, as follows: PeV-A1 (n = 4), PeV-A5 (n = 1), PeV-A6 (n = 1), and PeV-A14 (n = 1). Median age was 10.0 months (interquartile range 4.0-12.0 months), and other respiratory viruses were detected in all cases. Phylogenetic analysis showed that all detected PeV-A1 strains were in clade 1 A, which was a minor clade worldwide. Four PeV-A genotypes were detected in Myanmar. The clinical impact of PeV-A in children should be evaluated in future studies.

Comprehensive review of undifferentiated carcinoma of the pancreas: from epidemiology to treatment.

Undifferentiated carcinoma (UC) of the pancreas is a rare subtype of pancreatic cancer displaying no definitive direction of differentiation. UC has been reported as a highly aggressive malignant neoplasm, with a median overall survival of <1 year, except for several surgical series. On the other hand, UC tissue sometimes contains non-neoplastic osteoclast-like giant cells (OGCs), and such cases have been reported to have relatively longer survival. Thus, the World Health Organization (WHO) classification histologically distinguishes UC with OGCs (UCOGCs) from UC, and UCs were subclassified into three subtypes: anaplastic UC, sarcomatoid UC and carcinosarcoma. However, still less is known about UC due to its rarity, and such situations lead to further difficulties in treatment for UC. To date, only surgical resection can offer curative treatment for patients with UC, and no clear evidence for chemotherapy exists for them. However, a retrospective cohort study and case reports showed that relatively promising results paclitaxel-containing regimens for treatment of patients with unresectable UC. Furthermore, high programmed cell death protein 1 expression has been reported in sarcomatoid UCs and UCOGCs, and promising responses to anti-programmed death-ligand 1 therapy have been described in case reports of UCOGCs. Recent advances in chemotherapeutic agents and molecular technologies are opening up the possibilities for expanded treatments.

Visualization of Domain- and Concentration-Dependent Impact of Thrombomodulin on Differential Regulation of Coagulation and Fibrinolysis.

BACKGROUND: Thrombomodulin (TM) functions as a dual modulator-anticoagulant and antifibrinolytic potential-by the thrombin-dependent activation of protein C and thrombin-activatable fibrinolysis inhibitor (TAFI). Activated TAFI cleaves the C-terminal lysine of partially degraded fibrin and inhibits both plasminogen binding and its activation on the fibrin surface. We have reported previously that activated platelets initiate fibrin network formation and trigger fibrinolysis after the accumulation of tissue-type plasminogen activator and plasminogen. OBJECTIVE: To analyze the effects of domain-deletion variants of TM on coagulation and fibrinolysis at different concentrations. METHODS: Domain-deletion variants of TM, such as D123 (all extracellular regions), E3456 (minimum domains for thrombin-dependent activation of protein C and TAFI), and E456 (minimum domains for that of protein C but not TAFI), were used at 0.25 to 125 nM for turbidimetric assay to determine the clotting time and clot lysis time and to visualize fibrin network formation and lysis in platelet-containing plasma. RESULTS AND CONCLUSIONS: A low concentration of either D123 or E3456, but not of E456, prolonged clot lysis time, and delayed the accumulation of fluorescence-labeled plasminogen at the activated platelets/dense fibrin area due to effective TAFI activation. Conversely, only the highest concentrations of all three TM variants delayed the clotting time, though fibrin network formation in the vicinity of activated platelets was almost intact. TAFI activation might be affected by attenuation in thrombin activity after the clot formation phase. These findings suggest that the spatiotemporal balance between the anticoagulant and antifibrinolytic potential of TM is controlled in domain- and concentration-dependent manners.

COVID-19 and Thrombosis: Clinical Aspects.

In coronavirus disease 2019 (COVID-19), thrombus formation is related to the pathogenesis of acute respiratory distress syndrome (ARDS) and the progression of clinical symptoms. Severe damage to vascular endothelial cells and the associated cytokine storm after SARS-CoV-2 infection cause thrombogenesis and contribute to the development of more severe and unique thromboses compared to other infectious diseases. Thromboses occur more often in critically ill patients. In addition to pulmonary thromboembolism (PE) and deep vein thrombosis, acute myocardial infarction, peripheral arterial thrombosis, and aortic thrombosis have also been reported. In PE, thrombi develop in both pulmonary arteries and alveolar capillaries. These, together with intraalveolar fibrin deposition, interfere with effective gaseous exchange in the lungs and exacerbate the clinical symptoms of ARDS in patients with COVID-19. Pharmacological thromboprophylaxis is recommended for all hospitalized patients to prevent both thrombosis and aggravation of ARDS, and other organ failures. Although the pediatric population is mostly asymptomatic or develops mild disease after SARS-CoV-2 infection, a new inflammatory disorder affecting the cardiovascular system, multisystem inflammatory syndrome in children (MIS-C), has been reported. Similar to Kawasaki disease, acute myocarditis, coronary vasculitis, and aneurysms are typically seen in MISC, although these two are now considered distinct entities. A similar acute myocarditis is also observed in young male adults, in which a hyperinflammatory state after SARS-CoV-2 infection seems to be involved. Several side effects following vaccination against COVID-19 have been reported, including vaccine-induced immune thrombotic thrombocytopenia and acute myocarditis. Although these could be serious and life-threatening, the cases are very rare, thus, the benefits of immunization still outweigh the risks.

NKp44-based chimeric antigen receptor effectively redirects primary T cells against synovial sarcoma.

BACKGROUND: T-cell receptor-engineered T-cell therapies have achieved promising response rates against synovial sarcoma in clinical trials, but their applicability is limited owing to the HLA matching requirement. Chimeric antigen receptor (CAR) can redirect primary T cells to tumor-associated antigens without requiring HLA matching. However, various obstacles, including the paucity of targetable antigens, must be addressed for synovial sarcoma. Ligands for natural killer (NK) cell-activating receptors are highly expressed by tumor cells. METHODS: The surface expression of ligands for NK cell-activating receptors in synovial sarcoma cell lines was analyzed. We analyzed RNA sequencing data deposited in a public database to evaluate NKp44-ligand expression. Primary T cells retrovirally transduced with CAR targeting NKp44 ligands were evaluated for their functions in synovial sarcoma cells. Alterations induced by various stimuli, including a histone deacetylase inhibitor, a hypomethylating agent, inflammatory cytokines, and ionizing radiation, in the expression levels of NKp44 ligands were investigated. RESULTS: Ligands for NKp44 and NKp30 were expressed in all cell lines. NKG2D ligands were barely expressed in a single cell line. None of the cell lines expressed NKp46 ligand. Primary synovial sarcoma cells expressed the mRNA of the truncated isoform of MLL5, a known cellular ligand for NKp44. NKp44-based CAR T cells specifically recognize synovial sarcoma cells, secrete interferon-γ, and exert suppressive effects on tumor cell growth. No stimulus altered the expression of NKp44 ligands. CONCLUSION: NKp44-based CAR T cells can redirect primary human T cells to synovial sarcoma cells. CAR-based cell therapies may be an option for treating synovial sarcomas.

Conversion surgery for initially unresectable advanced biliary tract cancer treated with gemcitabine plus cisplatin combination chemotherapy: a case report and literature review.

Recently, the number of reports describing patients with initially unresectable biliary tract cancer (BTC) who underwent resection in the form of conversion surgery is increasing. Gemcitabine plus cisplatin (GC) combination therapy has been reported to significantly prolong the median survival time from 8.1 to 11.7 months compared with conventional gemcitabine therapy in patients with unresectable BTC. We report the case of a patient with unresectable BTC who underwent conversion surgery with a partial response to GC combination therapy. A 78-year-old woman was diagnosed with unresectable BTC with invasion of the right hepatic artery by lymph node metastasis and liver metastases. The patient received GC combination therapy. After 6 cycles of chemotherapy, the patient achieved a partial response. The radiological findings revealed a marked shrinkage in the primary lesion and the disappearance of lymph node and liver metastases. Therefore, the patient underwent conversion surgery, including biliary tract resection and regional lymph node dissection. For postoperative follow-up, the patient was monitored without receiving adjuvant chemotherapy. The patient had not exhibited recurrence during the 12-month follow-up period. We report the case of a patient with unresectable BTC who underwent conversion surgery with a partial response to GC combination therapy.

Reporting on the implementation to set up a "care and isolation facility" for mild COVID-19 cases in Tokyo.

The increasing number of COVID-19 cases has placed pressure on medical facilities. Against this backdrop, the Tokyo Metropolitan Government established a facility for mild and asymptomatic COVID-19 cases by using existing hotels. These kinds of facilities were established in several countries, and represented a spectrum from hotel-like to hospital-like care. In this article, we focused on implementation and related strategies for establishing such a facility in Tokyo as implementation research, while ensuring patient and staff safety. This facility had three functions: care, isolation, and buffering. For the implementation strategy, we used several strategies from the Expert Recommendations for Implementing Change (ERIC) to implement functions similar to an ordinary hospital, but using fewer inputs. This experience can be applied to other resource-limited settings such as that in less developed countries.

Clinical manifestations and outcome of viral acute lower respiratory infection in hospitalised children in Myanmar.

BACKGROUND: Acute lower respiratory infection (ALRI) remains the leading cause of death in children worldwide, and viruses have been the major cause of ALRI. In Myanmar, ALRI is associated with high morbidity and mortality in children, and detailed information on ALRI is currently lacking. METHODS: This prospective study investigated the viral aetiologies, clinical manifestations, and outcomes of ALRI in hospitalised children aged 1 month to 12 years at the Yankin Children Hospital, Yangon, Myanmar from May 2017 to April 2019. The sample size was set to 300 patients for each year. Two nasopharyngeal swabs were obtained for the patients with suspected viral ALRI; one for rapid tests for influenza and respiratory syncytial virus (RSV), and the other for real-time PCR for the 16 ALRI-causing viruses. Pneumococcal colonization rates were also investigated using real-time PCR. Clinical information was extracted from the medical records, and enrolled patients were categorised by age and severity for comparison. RESULTS: Among the 5463 patients admitted with a diagnosis of ALRI, 570 (10.4%) were enrolled in this study. The median age of the patients was 8 months (interquartile range, 4-15 months). The most common symptoms were cough (93%) and difficulty in breathing (73%), while the most common signs of ALRI were tachypnoea (78%) and chest indrawing (67%). A total of 16 viruses were detected in 502 of 570 patients' samples (88%), with RSV B (36%) and rhinovirus (28%) being the most commonly detected. Multiple viruses were detected in 221 of 570 samples (37%) collected from 570 patients. Severe ALRI was diagnosed in 107 of 570 patients (19%), and RSV B and human rhinovirus were commonly detected. The mortality rate was 5%; influenza virus A (29%) and RSV B (21%) were commonly detected, and stunting and lack of immunization were frequently observed in such cases. Additionally, 45% (259/570) of the patients had pneumococcal colonization. CONCLUSIONS: Viral ALRI in hospitalised children with a median of 8 months has significant morbidity and mortality rates in Myanmar. RSV and rhinovirus were the most commonly detected from nasopharyngeal swabs, while influenza virus and RSV were the most frequently associated with fatal cases.

Development of a direct point electron beam exposure system to investigate the biological functions of subcellular domains in a living biological cell.

Electron microscopy studies have demonstrated that the diameter of a focused electron beam is small enough to probe or manipulate subcellular domains of a single biological cell. Here, we report the development of a direct point electron beam irradiation system to investigate the biological functions of subcellular domains in a living cell. Subcellular structures of a single living cell cultured on a thin film can be selectively irradiated by the point electron beam generated by our system. We have demonstrated controlled beam positioning capability to selectively irradiate 500 nm size structure with a point electron beam. We determined beam irradiation parameters that did not cause irreversible plasma membrane perforation after beam exposure and the irradiation caused intracellular Ca2+ elevation in an irradiated neuronal cell. Since the neuronal cell express fine subcellular structures such as neurites, we tried to position a beam on the structure and observed a Ca2+ wave originated from the intended point, which showed that our system had enough selectivity to target a subcellular structure. Point electron beam exposure is expected to be employed for various cellular stimulation protocols, and this enables the investigation of the biological functions of subcellular domains.

Pre-administration of a carboxypeptidase inhibitor enhances tPA-induced thrombolysis in mouse microthrombi: Evidence from intravital imaging analysis.

INTRODUCTION: Thrombolysis using recombinant tissue-type plasminogen activator (rt-PA) is the pharmacological treatment of choice in acute thrombotic events. However, a narrow therapeutic window and bleeding complications limit its use. We describe the role of carboxypeptidase inhibitor from potato tuber (PTCI), an inhibitor of activated thrombin-activatable fibrinolysis inhibitor (TAFIa), on Glu-plasminogen accumulation and microthrombus dynamics in vivo and demonstrate its influence on rt-PA-mediated thrombolysis. MATERIALS AND METHODS: In conjunction with real-time intravital two-photon excitation fluorescence microscopy, we produced and imaged laser-induced microthrombi in the mesenteric venules of Green Fluorescent Protein (GFP)-expressing mice. We examined microthrombus dynamics and thrombolysis patterns in vivo by measuring the changes in the fluorescence intensity of labeled Glu-plasminogen following administration of epsilon aminocaproic acid (EACA), PTCI, and rt-PA. RESULTS: PTCI enhanced Glu-plasminogen accumulation at the core of the thrombus by inhibiting TAFIa, while EACA inhibited this process. Exogenous rt-PA effectively triggered Glu-plasminogen activation within the thrombus and promoted thrombolysis. Administration of PTCI and rt-PA together showed no significant benefit on thrombolysis compared to rt-PA administration alone. However, early-phase systemic administration of PTCI before thrombolytic therapy by rt-PA expedited clot lysis as evidenced by significantly faster time to reach peak Glu-plasminogen fluorescence intensity and shorter time to achieve near-complete clot lysis (P = 0.014 and P = 0.003, respectively). CONCLUSIONS: PTCI potentiates rt-PA-mediated thrombolysis when administered early in acute thrombotic events. Further studies are warranted to explore the potential of TAFI inhibitors as adjunct agents in thrombolysis or thromboprophylaxis.

Demonstration of Three Distinct High-Molecular-Weight Complexes between Plasminogen Activator Inhibitor Type 1 and Tissue-Type Plasminogen Activator.

BACKGROUND: Details of the molecular interaction between tissue-type plasminogen activator (tPA) and plasminogen activator inhibitor type-1 (PAI-1) remain unknown. METHODS AND RESULTS: Three distinct forms of high-molecular-weight complexes are demonstrated. Two of the forms were detected by mass spectrometry. The high molecular mass detected by MALDI-TOF MS (matrix-assisted laser desorption ionization-time of flight mass spectrometry) was 107,029 Da, which corresponds to the sum of molecular masses of the intact tPA (65,320 Da) and the intact PAI-1 (42,416 Da). The lower molecular mass was 104,367 Da and is proposed to lack the C-terminal bait peptide of PAI-1 (calculated mass: 3,804 Da), which was detected as a 3,808 Da fragment. When the complex was analyzed by SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis), only a single band was observed. However, after treatment by SDS and Triton X-100, two distinct forms of the complex with different mobilities were shown by SDS-PAGE. The higher molecular weight band demonstrated specific tPA activity on fibrin autography, whereas the lower molecular weight band did not. Peptide sequence analysis of these two bands, however, unexpectedly revealed the existence of the C-terminal cleavage peptide in both bands and its amount was less in the upper band. In the upper band, the sequences corresponding to the regions at the interface between two molecules in its Michaelis intermediate were diminished. Thus, these two bands corresponded to distinct nonacyl-enzyme complexes, wherein only the upper band liberated free tPA under the conditions employed. CONCLUSION: These data suggest that under physiological conditions a fraction of the tPA-PAI-1 population exists as nonacylated-enzyme inhibitor complex.

Switching from entecavir to tenofovir disoproxil fumarate for HBeAg-positive chronic hepatitis B patients: a phase 4, prospective study.

BACKGROUND: Tenofovir disoproxil fumarate (TDF) is widely used and recommended as first-line treatment for patients infected with the hepatitis B virus (HBV). However, current data are limited regarding the efficacy and safety of switching to TDF for the treatment of chronic hepatitis B in hepatitis B e-antigen (HBeAg)-positive patients who are virologically suppressed with another nucleos(t)ide analogue. The primary objective of this study was to evaluate the hepatitis B surface antigen (HBsAg) reduction potential of switching from entecavir (ETV) to TDF at week 48 in HBeAg-positive chronic hepatitis B patients with undetectable serum HBV-DNA. METHODS: In this multicenter, single-arm, open-label, phase 4 clinical study, 75 participants currently treated with ETV 0.5 mg once daily were switched to TDF 300 mg once daily for 96 weeks. RESULTS: At week 48, 3/74 participants (4%) achieved 0.25 log10 reduction of HBsAg levels from baseline (the primary endpoint). Mean HBsAg reduction was -0.14 log10 IU/mL and 12% (9/74) achieved 0.25 log10 reduction by 96 weeks. No participants achieved HBsAg seroclearance. HBsAg reduction at weeks 48 and 96 was numerically greater in participants with higher alanine aminotransferase levels (≥ 60 U/L). Seventeen participants (25%) achieved HBeAg seroclearance up to week 96. No participants experienced viral breakthrough. All drug-related adverse events (18 participants [24%]) were mild in intensity, including an increase in urine beta-2-microglobulin (15 participants [20%]). CONCLUSIONS: In conclusion, HBsAg reduction was limited after switching from ETV to TDF in this study population. Further investigation is warranted to better understand the clinical impact of switching from ETV to TDF. ClinicalTrials.gov: NCT03258710 registered August 21, 2017. https://clinicaltrials.gov/ct2/show/NCT03258710?term=NCT03258710&draw=2&rank=1.

Silver/ThioClickFerrophos-Catalyzed 1,3-Dipolar Cycloaddition and Tandem Addition-Elimination Reaction of Morita-Baylis-Hillman Adducts.

The asymmetric 1,3-dipolar cycloaddition of glycine imino esters to Morita-Baylis-Hillman (MBH) adducts or acetylated MBH adducts is described. The reaction was efficiently catalyzed by AgOAc/(R,Sp)-ThioClickFerrophos at room temperature to afford pyrrolidine derivatives bearing a quaternary carbon as a single diastereomer with excellent enantioselectivity. When a cyclic pyrroline ester was used as the nucleophile instead of a glycine imino ester, the enantioselective tandem addition-elimination reaction with an acetylated MBH adduct proceeded with an excellent yield and enantioselectivity, resulting in the formation of an exo-olefin. The wide substrate scope of these reactions and the transformability of the products enable expeditious access to divergent multifunctionalized pyrrolidines in an optically pure fashion.

Mesenchymal stem cells derived from human induced pluripotent stem cells improve the engraftment of myogenic cells by secreting urokinase-type plasminogen activator receptor (uPAR).

BACKGROUND: Duchenne muscular dystrophy (DMD) is a severe X-linked recessive disease caused by mutations in the dystrophin gene. Transplantation of myogenic stem cells holds great promise for treating muscular dystrophies. However, poor engraftment of myogenic stem cells limits the therapeutic effects of cell therapy. Mesenchymal stem cells (MSCs) have been reported to secrete soluble factors necessary for skeletal muscle growth and regeneration. METHODS: We induced MSC-like cells (iMSCs) from induced pluripotent stem cells (iPSCs) and examined the effects of iMSCs on the proliferation and differentiation of human myogenic cells and on the engraftment of human myogenic cells in the tibialis anterior (TA) muscle of NSG-mdx4Cv mice, an immunodeficient dystrophin-deficient DMD model. We also examined the cytokines secreted by iMSCs and tested their effects on the engraftment of human myogenic cells. RESULTS: iMSCs promoted the proliferation and differentiation of human myogenic cells to the same extent as bone marrow-derived (BM)-MSCs in coculture experiments. In cell transplantation experiments, iMSCs significantly improved the engraftment of human myogenic cells injected into the TA muscle of NSG-mdx4Cv mice. Cytokine array analysis revealed that iMSCs produced insulin-like growth factor-binding protein 2 (IGFBP2), urokinase-type plasminogen activator receptor (uPAR), and brain-derived neurotrophic factor (BDNF) at higher levels than did BM-MSCs. We further found that uPAR stimulates the migration of human myogenic cells in vitro and promotes their engraftment into the TA muscles of immunodeficient NOD/Scid mice. CONCLUSIONS: Our results indicate that iMSCs are a new tool to improve the engraftment of myogenic progenitors in dystrophic muscle.

Radiation doses to the eye lenses of radiologic technologists who assist patients undergoing computed tomography.

The present study aimed to determine the amount of radiation exposure to the eye lenses of radiologic technologists while assisting patients undergoing computed tomography imaging and the effects of wearing lead glasses on dose reduction. Monthly radiation doses were collected for 12 months. Dose quantities at a depth of 3 mm (Hp(3)) were measured at the neck using personal optically stimulated luminescence (OSL) dosimeters. We also estimated Hp(3) as converted air kerma using small OSL dosimeters at the neck and at six positions on the lead glasses near the eyes. The total dose-length product at the time of patient assistance was 53,341 mGy·cm/y. The Hp(3) from the personal dosimeter was 9.13 mSv/y and the highest dose recorded by the small OSL dosimeters attached outside the lead glasses was 8.47 mSv/y. The lead glasses reduced the radiation exposure by ~ 60%.

Periostin Is Required for the Maintenance of Muscle Fibers during Muscle Regeneration.

Skeletal muscle regeneration is a well-organized process that requires remodeling of the extracellular matrix (ECM). In this study, we revealed the protective role of periostin, a matricellular protein that binds to several ECM proteins during muscle regeneration. In intact muscle, periostin was localized at the neuromuscular junction, muscle spindle, and myotendinous junction, which are connection sites between muscle fibers and nerves or tendons. During muscle regeneration, periostin exhibited robustly increased expression and localization at the interstitial space. Periostin-null mice showed decreased muscle weight due to the loss of muscle fibers during repeated muscle regeneration. Cultured muscle progenitor cells from periostin-null mice showed no deficiencies in their proliferation, differentiation, and the expression of Pax7, MyoD, and myogenin, suggesting that the loss of muscle fibers in periostin-null mice was not due to the impaired function of muscle stem/progenitor cells. Periostin-null mice displayed a decreased number of CD31-positive blood vessels during muscle regeneration, suggesting that the decreased nutritional supply from blood vessels was the cause of muscle fiber loss in periostin-null mice. These results highlight the novel role of periostin in maintaining muscle mass during muscle regeneration.

Pharmacological activation of SERCA ameliorates dystrophic phenotypes in dystrophin-deficient mdx mice.

Duchenne muscular dystrophy (DMD) is an X-linked genetic disorder characterized by progressive muscular weakness because of the loss of dystrophin. Extracellular Ca2+ flows into the cytoplasm through membrane tears in dystrophin-deficient myofibers, which leads to muscle contracture and necrosis. Sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) takes up cytosolic Ca2+ into the sarcoplasmic reticulum, but its activity is decreased in dystrophic muscle. Here, we show that an allosteric SERCA activator, CDN1163, ameliorates dystrophic phenotypes in dystrophin-deficient mdx mice. The administration of CDN1163 prevented exercise-induced muscular damage and restored mitochondrial function. In addition, treatment with CDN1163 for 7 weeks enhanced muscular strength and reduced muscular degeneration and fibrosis in mdx mice. Our findings provide preclinical proof-of-concept evidence that pharmacological activation of SERCA could be a promising therapeutic strategy for DMD. Moreover, CDN1163 improved muscular strength surprisingly in wild-type mice, which may pave the new way for the treatment of muscular dysfunction.

PCR detection rates for serum and cerebrospinal fluid from neonates and young infants infected with human parechovirus 3 and enteroviruses.

BACKGROUND: Human parechovirus 3 (HPeV-3) and enteroviruses (EV) are commonly detected viruses in febrile neonates and young infants and are usually diagnosed by PCR. However, in this population, data on detection rates for samples from different anatomical sites are limited. OBJECTIVES: To determine PCR detection rates for HPeV-3 and EVs in serum and cerebrospinal fluid (CSF) samples from febrile neonates and young infants. STUDY DESIGN: This prospective study identified viruses in serum and CSF samples collected from febrile neonates and young infants (age <4 months) in Niigata, Japan, during 2014-2018. HPeV-3 or EV infection was defined as a positive quantitative real-time PCR result for the virus in serum or CSF. Genotypes were identified by sequence analyses of the viral protein 1 region. RESULTS: Among 216 patients, we identified 56 HPeV-3-infected (26 %) and 48 EV-infected patients (22 %). All (56/56; 100 %) HPeV-3-infected patients had a positive PCR result for serum, and 49/56 (88 %) had a positive result for CSF. In EV-infected patients, 40/48 (83 %) were positive for serum, and 34/48 (71 %) were positive for CSF, and 22/48 (46 %) were positive for serum (n = 14) or CSF (n = 8). If only a CSF sample had been obtained, 7 (12 %) HPeV-3 infections and 14 (29 %) EV infections would have been undiagnosed. Detection rates in serum and CSF differed by genotype in EV-infected patients. CONCLUSIONS: Viral RNA detection rates differed between serum and CSF in HPeV-3- and EV-infected neonates/infants. Combined evaluation of serum and CSF samples is important for accurate viral diagnosis in this population.