硝子体手術におけるテノン嚢下麻酔と経テノン嚢球後麻酔の疼痛と眼球運動抑制の比較

藤田医科大

Spatiotemporal analysis of the UPR transition induced by methylmercury in the mouse brain

Methylmercury (MeHg), an environmental toxicant, induces neuronal cell death and injures a specific area of the brain. MeHg-mediated neurotoxicity is believed to be caused by oxidative stress and endoplasmic reticulum (ER) stress but the mechanism by which those stresses lead to neuronal loss is unclear. Here, by utilizing the ER stress-activated indicator (ERAI) system, we investigated the signaling alterations in the unfolded protein response (UPR) prior to neuronal apoptosis in the mouse brain. In ERAI transgenic mice exposed to MeHg (25 mg/kg, S.C.), the ERAI signal, which indicates activation of the cytoprotective pathway of the UPR, was detected in the brain. Interestingly, detailed ex vivo analysis showed that the ERAI signal was localized predominantly in neurons. Time course analysis of MeHg exposure (30 ppm in drinking water) showed that whereas the ERAI signal was gradually attenuated at the late phase after increasing at the early phase, activation of the apoptotic pathway of the UPR was enhanced in proportion to the exposure time. These results suggest that MeHg induces not only ER stress but also neuronal cell death via a UPR shift. UPR modulation could be a therapeutic target for treating neuropathy caused by electrophiles similar to MeHg

Improved Sendai viral system for reprogramming to naive pluripotency

優れた多分化能を持つヒトのナイーブ型iPS細胞を迅速に作製する方法を発明. 京都大学プレスリリース. 2022-10-18.A novel method for generating naive human iPS cells with significantly higher differentiation potency. 京都大学プレスリリース. 2022-11-15.Naive human induced pluripotent stem cells (iPSCs) can be generated by reprogramming somatic cells with Sendai virus (SeV) vectors. However, only dermal fibroblasts have been successfully reprogrammed this way, and the process requires culture on feeder cells. Moreover, SeV vectors are highly persistent and inhibit subsequent differentiation of iPSCs. Here, we report a modified SeV vector system to generate transgene-free naive human iPSCs with superior differentiation potential. The modified method can be applied not only to fibroblasts but also to other somatic cell types. SeV vectors disappear quickly at early passages, and this approach enables the generation of naive iPSCs in a feeder-free culture. The naive iPSCs generated by this method show better differentiation to trilineage and extra-embryonic trophectoderm than those derived by conventional methods. This method can expand the application of iPSCs to research on early human development and regenerative medicine

Inactivation of the Influenza Virus by a Supplemental Fermented Plant Product (Manda Koso)

Manda Koso is a commercial fermented plant product (FPP) made from 53 types of fruits and vegetables that are fermented for more than 3 years. We hypothesized that the FPP can prevent infection by influenza virus and human norovirus. Therefore, we investigated the effects of the FPP on influenza virus and feline calicivirus, a surrogate of human norovirus. We found that 10% FPP inactivated the influenza virus but not the feline calicivirus. Inhibition of the influenza virus was highly concentration-dependent: 1% and 0.3% FPP showed reduced inactivation efficacy. The effects of the FPP on the influenza virus-infected cells were investigated by addition of the FPP to the culture medium after virus infection. No suppressive effect of the FPP on influenza replication in MDCK cells was observed. The results showed that the FPP could inactivate influenza virus by affecting the virus particles

Situs inversus and cystic kidney disease: Two adult patients with this heterogeneous syndrome

Background: Situs inversus is a rare complication of cystic kidney diseases. Only three genes, INVS (NPHP2), NPHP3 and PKD2 have been proved to be responsible for some cases, while the responsible genes in many others are still unknown. Case Reports: Here we report two male patients with situs inversus combined with cystic kidney disease without any family history of polycystic kidney disease. Their renal function was normal in childhood but culminated in end stage renal disease in middle age. No pathogenic mutations were found in mutation analysis of INVS, IFT88, PKD2, UMOD or NPHP3 in them. Conclusions: Past reported cases of situs inversus and cystic kidney diseases were divided into three groups, i.e., gestational lethal renal dysplasia group, infantile or juvenile nephronophthisis group and polycystic kidney disease group. The present patients are different from each of these groups. Moreover, the renal lesions of the present two cases are quite different from each other, with one showing mildly atrophic kidneys with small numbers of cysts and the other an enlarged polycystic kidney disease, suggesting very heterogeneous entities

A cell-based high-throughput screening method to directly examine transthyretin amyloid fibril formation at neutral pH

Transthyretin (TTR) is a major amyloidogenic protein associated with hereditary (ATTRm) and nonhereditary (ATTRwt) intractable systemic transthyretin amyloidosis. The pathological mechanisms of ATTR-associated amyloid fibril formation are incompletely understood, and there is a need for identifying compounds that target ATTR. C-terminal TTR fragments are often present in amyloid-laden tissues of most patients with ATTR amyloidosis, and on the basis of in vitro studies, these fragments have been proposed to play important roles in amyloid formation. Here, we found that experimentally-formed aggregates of full-length TTR are cleaved into C-terminal fragments, which were also identified in patients' amyloid-laden tissues and in SH-SY5Y neuronal and U87MG glial cells. We observed that a 5-kDa C-terminal fragment of TTR, TTR81–127, is highly amyloidogenic in vitro, even at neutral pH. This fragment formed amyloid deposits and induced apoptosis and inflammatory gene expression also in cultured cells. Using the highly amyloidogenic TTR81–127 fragment, we developed a cell-based high-throughput screening method to discover compounds that disrupt TTR amyloid fibrils. Screening a library of 1280 off-patent drugs, we identified two candidate repositioning drugs, pyrvinium pamoate and apomorphine hydrochloride. Both drugs disrupted patient-derived TTR amyloid fibrils ex vivo, and pyrvinium pamoate also stabilized the tetrameric structure of TTR ex vivo in patient plasma. We conclude that our TTR81–127–based screening method is very useful for discovering therapeutic drugs that directly disrupt amyloid fibrils. We propose that repositioning pyrvinium pamoate and apomorphine hydrochloride as TTR amyloid-disrupting agents may enable evaluation of their clinical utility for managing ATTR amyloidosis

精神的ストレスによるアレルギー性気道炎症の増悪

Stress and other psychological factors have long been hypothesized to be associated with asthma symptoms. One of the fundamental features of bronchial asthma is chronic airway inflammation, characteristic of the infiltration and activation of inflammatory cells, such as eosinophils and T lymphocytes. Psychological stress can modulate the inflammatory response through activation of hypothalamus-pituitary-adrenal axis and the sympathetic nervous system increasing the secretion of cortisol and catecholamines. However, the mechanisms linking stress and asthma are not well defined. Therefore, we investigated the effects of psychological stress on asthmatic airway inflammation using a murine model of allergic asthma. Female BALB/c mice and C57BL/6J mice were exposed to restraint stress (RS) during the antigen inhalation, which procedure was repeated 3 times for every seven days. Seven days after the last procedure, the mice were challenged with ovalbumin (OVA), and the airway inflammation was evaluated by the numbers of inflammatory cells in bronchoalveolar lavage fluids. RS significantly increased the numbers of total cells and lymphocytes in BALB/c mice. In C57BL/6J mice, in contrast, the numbers of inflammatory cells were not significantly different between mice exposed and not exposed to RS. Our findings suggest that psychological stress can enhance antigen-induced airway inflammation and, furthermore, that genetic background is involved in the pathogenesis of stress-induced asthma. This model using female BALB/c mice may be useful to elucidate the mechanisms by which psychological stress exacerbates asthma symptoms

SARS-CoV-2 B.1.617.2 Delta variant replication and immune evasion

Abstract: The B.1.617.2 (Delta) variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first identified in the state of Maharashtra in late 2020 and spread throughout India, outcompeting pre-existing lineages including B.1.617.1 (Kappa) and B.1.1.7 (Alpha)1. In vitro, B.1.617.2 is sixfold less sensitive to serum neutralizing antibodies from recovered individuals, and eightfold less sensitive to vaccine-elicited antibodies, compared with wild-type Wuhan-1 bearing D614G. Serum neutralizing titres against B.1.617.2 were lower in ChAdOx1 vaccinees than in BNT162b2 vaccinees. B.1.617.2 spike pseudotyped viruses exhibited compromised sensitivity to monoclonal antibodies to the receptor-binding domain and the amino-terminal domain. B.1.617.2 demonstrated higher replication efficiency than B.1.1.7 in both airway organoid and human airway epithelial systems, associated with B.1.617.2 spike being in a predominantly cleaved state compared with B.1.1.7 spike. The B.1.617.2 spike protein was able to mediate highly efficient syncytium formation that was less sensitive to inhibition by neutralizing antibody, compared with that of wild-type spike. We also observed that B.1.617.2 had higher replication and spike-mediated entry than B.1.617.1, potentially explaining the B.1.617.2 dominance. In an analysis of more than 130 SARS-CoV-2-infected health care workers across three centres in India during a period of mixed lineage circulation, we observed reduced ChAdOx1 vaccine effectiveness against B.1.617.2 relative to non-B.1.617.2, with the caveat of possible residual confounding. Compromised vaccine efficacy against the highly fit and immune-evasive B.1.617.2 Delta variant warrants continued infection control measures in the post-vaccination era

Differential Effects of Infant Vocalizations on Approach-Avoidance Postural Movements in Mothers

Infant vocalization plays a pivotal role in communicating infant mood to parents and thereby motivating parenting responses. Although many psychological and neural responses to infant vocalization have been reported, few studies have examined maternal approach-avoidance behavior in response to infant vocalization. Thus, this research sought to determine how infant emotional vocalization affects maternal behavior. Twenty mothers participated in this behavioral study, all of whom had infants of 24 months old or less. In the experiment, they stood on a Balance Board that collected real-time data regarding center of pressure (COP), while listening to a series of infant vocalizations including cry, laugh, and babbling. They then listened to the same vocalizations for a second time and rated their felt emotions in response to each vocalization. The participants demonstrated significant postural movements of approaching in response to cry stimuli or to stimuli regarded as highly urgent. In contrast, they demonstrated postural movement of avoidance in response to laugh vocalization. These findings suggest that parenting behavior in response to infant emotional vocalization is regulated not by the pleasant-unpleasant axis but by the urgency of the stimulus