Uniform Suspension of Heat-Killed Staphylococcus aureus for a Positive Control Used in the Monocyte-Activation Test.

Pyrogens, classified as bacterial endotoxins and non-endotoxin pyrogens (NEPs), induce fever or shock when released into the bloodstream or spinal fluid. Recently, a monocyte-activation test (MAT) involving human cell culture has been developed to detect pyrogens in injectable products. To evaluate the sensitivity of MAT, a reference standard endotoxin was used as a positive control; however, the reactivity differed between the endotoxins and NEPs, necessitating positive controls for NEPs. This study aimed to explore a preparation method for heat-killed Staphylococcus aureus (HKSA) as a positive control for NEPs in MAT. Because S. aureus forms grape-like clusters, nine types of glass filters with pore sizes of 0.5-2.7 µm were evaluated to obtain a uniform bacterial suspension. The suspension was then heat-treated to kill the bacteria, resulting in HKSA samples. Serial dilutions of HKSA were tested by MAT using peripheral blood mononuclear cells. The interleukin-6 concentrations in the culture supernatant were measured by enzyme-linked immuno-sorbent assay to assess pyrogenic activities of HKSA. The pore sizes of the glass filters affected the uniformity of HKSA, and GF/C filter was selected for HKSA preparation. Repeated filtration improved uniformity, and a uniform suspension of HKSA was obtained through double filtration using a GF/C filter. Despite the decrease in HKSA activity as filtration frequency increased, the detection limit remained consistently unchanged. This suggests that repeated filtration can adjust the activity of HKSA to a baseline level and that a uniform suspension of HKSA exhibiting low variation is suitable as a positive control in MAT.

Impact of Repetitive Transcranial Magnetic Stimulation to the Cerebellum on Performance of a Ballistic Targeting Movement.

This study aimed to investigate the effects of repetitive transcranial magnetic stimulation (rTMS) of the cerebellum on changes in motor performance during a series of repetitive ballistic-targeting tasks. Twenty-two healthy young adults (n = 12 in the active-rTMS group and n = 10 in the sham rTMS group) participated in this study. The participants sat on a chair in front of a monitor and fixed their right forearms to a manipulandum. They manipulated the handle with the flexion/extension of the wrist to move the bar on the monitor. Immediately after a beep sound was played, the participant moved the bar as quickly as possible to the target line. After the first 10 repetitions of the ballistic-targeting task, active or sham rTMS (1 Hz, 900 pulses) was applied to the right cerebellum. Subsequently, five sets of 100 repetitions of this task were conducted. Participants in the sham rTMS group showed improved reaction time, movement time, maximum velocity of movement, and targeting error after repetition. However, improvements were inhibited in the active-rTMS group. Low-frequency cerebellar rTMS may disrupt motor learning during repetitive ballistic-targeting tasks. This supports the hypothesis that the cerebellum contributes to motor learning and motor-error correction in ballistic-targeting movements.

Mental health in Japanese children during school closures due to the COVID-19.

BACKGROUND: Changes in relationships, sleep rhythms, and physical activity caused by school closures instituted to curb the spread of COVID-19 influenced children's mental health. We explored changes in children's daily life and effects on their mental health during school closures. METHODS: Participants included elementary and junior high school students 9 years of age and older seen in the outpatient clinic during school closures and were required to complete the Japanese version of WHO Five Well-Being Index (WHO-5-J). The results were compared with those of students seen after schools reopened. RESULTS: Participants included 78 students in the school closure group and 113 in the school reopening group. Although those in the closure group devoted more time to family and sleep, their sleep rhythms, eating habits, and physical activities were disrupted. Although there were no significant differences between the two groups in total WHO-5-J scores, single WHO-5-J items such as activity and vigor and interest were significantly worse and rest was significantly better in the school closure group. CONCLUSION: Although school closures resulted in elementary and junior high school students spending more time with family and sleeping, their sleep rhythms, eating habits, and physical activities were disrupted. As the children's living environment changed, they felt less active and vigorous and had difficulty finding things that interested them. However, their sleep improved and overall, the number of children with potential mental health problems did not change.

Evaluating the mental health of children in a local hospital outpatient clinic.

BACKGROUND: The 30-item Questionnaire for Triage and Assessment (QTA30) is a standardized triage and assessment tool for assessing pediatric psychosomatic disorders. It is estimated that one in 10 children in Japan experience difficulties in their school life. Using the QTA30 we evaluated mental health in children at an outpatient clinic in a local hospital. METHODS: All elementary and junior high school students (≥9 years) who visited our institution between December 1 2019 and March 31 2020 were asked to complete the QTA30. RESULT: A total of 372 children responded. Half of the children with a psychosomatic disorder and 9% of children with other chronic disorders were suspected to have poor mental health. Suspected poor mental health was associated with higher odds of female gender (odds ratio [OR]: 1.89, 95% confidence interval [CI]: 1.07-3.39), junior high school students (OR: 3.73, 95% CI: 2.11-6.73), and not enjoying exercise (OR: 2.13, 95% CI: 1.16-3.9). The mean ± standard deviation total QTA30 score was significantly worse in children with psychosomatic disorders (38.0 ± 19.1) among children with other chronic diseases; however, only the score in children with central precocious puberty (27.4 ± 13.7) showed no difference. CONCLUSION: Based on our survey, the percentage of children suspected to have mental health problems manifesting as non-psychosomatic chronic disorders was similar to the proportion of children suspected to experience difficulties with their school life. Pediatricians should carefully consider the possibility of mental health problems when children are seen in regular visits to the outpatient clinic.

Vaporized Hydrogen Peroxide and Ozone Gas Synergistically Reduce Prion Infectivity on Stainless Steel Wire.

Prions are infectious agents causing prion diseases, which include Creutzfeldt-Jakob disease (CJD) in humans. Several cases have been reported to be transmitted through medical instruments that were used for preclinical CJD patients, raising public health concerns on iatrogenic transmissions of the disease. Since preclinical CJD patients are currently difficult to identify, medical instruments need to be adequately sterilized so as not to transmit the disease. In this study, we investigated the sterilizing activity of two oxidizing agents, ozone gas and vaporized hydrogen peroxide, against prions fixed on stainless steel wires using a mouse bioassay. Mice intracerebrally implanted with prion-contaminated stainless steel wires treated with ozone gas or vaporized hydrogen peroxide developed prion disease later than those implanted with control prion-contaminated stainless steel wires, indicating that ozone gas and vaporized hydrogen peroxide could reduce prion infectivity on wires. Incubation times were further elongated in mice implanted with prion-contaminated stainless steel wires treated with ozone gas-mixed vaporized hydrogen peroxide, indicating that ozone gas mixed with vaporized hydrogen peroxide reduces prions on these wires more potently than ozone gas or vaporized hydrogen peroxide. These results suggest that ozone gas mixed with vaporized hydrogen peroxide might be more useful for prion sterilization than ozone gas or vaporized hydrogen peroxide alone.

Nuclear movement regulated by non-Smad Nodal signaling via JNK is associated with Smad signaling during zebrafish endoderm specification.

Asymmetric nuclear positioning is observed during animal development, but its regulation and significance in cell differentiation remain poorly understood. Using zebrafish blastulae, we provide evidence that nuclear movement towards the yolk syncytial layer, which comprises extraembryonic tissue, occurs in the first cells fated to differentiate into the endoderm. Nodal signaling is essential for nuclear movement, whereas nuclear envelope proteins are involved in movement through microtubule formation. Positioning of the microtubule-organizing center, which is proposed to be crucial for nuclear movement, is regulated by Nodal signaling and nuclear envelope proteins. The non-Smad JNK signaling pathway, which is downstream of Nodal signaling, regulates nuclear movement independently of the Smad pathway, and this nuclear movement is associated with Smad signal transduction toward the nucleus. Our study provides insight into the function of nuclear movement in Smad signaling toward the nucleus, and could be applied to the control of TGFß signaling.

Occludin as a functional marker of vascular endothelial cells on tube-forming activity.

Cell therapy using endothelial progenitor cells (EPCs) is a promising strategy for the treatment of ischemic diseases. Two types of EPCs have been identified: early EPCs and late EPCs. Late EPCs are able to form tube structure by themselves, and have a high proliferative ability. The functional marker(s) of late EPCs, which relate to their therapeutic potential, have not been fully elucidated. Here we compared the gene expression profiles of several human cord blood derived late EPC lines which exhibit different tube formation activity, and we observed that the expression of occludin (OCLN) in these lines correlated with the tube formation ability, suggesting that OCLN is a candidate functional marker of late EPCs. When OCLN was knocked down by transfecting siRNA, the tube formation on Matrigel, the S phase + G2 /M phase in the cell cycle, and the spheroid-based sprouting of late EPCs were markedly reduced, suggesting the critical role of OCLN in tube formation, sprouting, and proliferation. These results indicated that OCLN plays a novel role in neovascularization and angiogenesis.

The N-terminal domain of gastrulation brain homeobox 2 (Gbx2) is required for iridophore specification in zebrafish.

Although body color pattern formation by pigment cells plays critical roles in animals, pigment cell specification has not yet been fully elucidated. In zebrafish, there are three chromatophores: melanophore, iridophore, and xanthophore, that are derived from neural crest cells (NCCs). A recent study has reported the differentially expressed genes between melanophores and iridophores. Based on transcriptome data, we identified that Gbx2 is required for iridophore specification during development. In support of this, iridophore formation is suppressed by gbx2 knockdown by morpholino antisense oligonucleotide, at 72 h post fertilization (hpf) in zebrafish. Moreover, gbx2 is expressed in sox10-expressing NCCs and guanine crystal plates-containing iridophores during development at 24 and 48 hpf, respectively. In gbx2 knockdown zebrafish embryos, apoptosis of sox10-expressing NCCs was detected at 24 hpf without any effect on the formation of melanophores and xanthophores at 48 hpf. We further observed that the N-terminal domain of Gbx2 is able to rescue the iridophore formation defect caused by gbx2 knockdown. Our study provides insights into the requirement of N-terminal domain of Gbx2 for iridophore specification in zebrafish.

Effectiveness of Home-Based Exercises Without Supervision by Physical Therapists for Patients With Early-Stage Amyotrophic Lateral Sclerosis: A Pilot Study.

OBJECTIVE: To verify the effects of structured home-based exercises without supervision by a physical therapist in patients with early-stage amyotrophic lateral sclerosis (ALS). DESIGN: A historical controlled study that is part of a multicenter collaborative study. SETTING: Rehabilitation departments at general hospitals and outpatient clinics with a neurology department. PARTICIPANTS: Patients (N=21) with ALS were enrolled and designated as the home-based exercise (Home-EX) group, and they performed unsupervised home-based exercises. As a control group, 84 patients with ALS who underwent supervised exercise with a physical therapist for 6 months were extracted from a database of patients with ALS and matched with the Home-EX group in terms of their basic attributes and clinical features. INTERVENTION: The Home-EX group was instructed to perform structured home-based exercises without supervision by a physical therapist that consisted of muscle stretching, muscle training, and functional training for 6 months. MAIN OUTCOME MEASURES: The primary outcome was the score on the ALS Functional Rating Scale-Revised (ALSFRS-R), which is composed of 3 domains: bulbar function, limb function, and respiratory function. The score ranges from 0 to 48 points, with a higher score indicating better function. RESULTS: In the Home-EX group, 15 patients completed the home-based exercises for 6 months, and 6 patients dropped out because of medical reasons or disease progression. No adverse events were reported. The Home-EX group was found to have a significantly higher respiratory function subscore and total score on the ALSFRS-R than the control group at follow-up (P<.001 and P<.05, respectively). CONCLUSIONS: Structured home-based exercises without supervision by a physical therapist could be used to alleviate functional deterioration in patients with early-stage ALS.

[SENSITIZATION PATTERN FOR INHALED AND FOOD ALLERGENS IN JAPANESE RECURRENT WHEEZERS UNDER 60 MONTHS OF AGE].

BACKGROUND: Allergen sensitization differs according to countries and regions. Understanding the characteristics of allergen sensitization in one's own country is useful for the treatment of patients with allergic diseases. Recently, Japanese cedar pollen (JCP) sensitization is increasing in young Japanese children. Therefore, we evaluated allergen sensitization patterns in under 60-month-old Japanese recurrent wheezers using multiple allergen tests. METHODS: Allergen tests for 204 Japanese recurrent wheezers between April 2010 and April 2016 were reviewed. Children were divided into 10 groups by age, in 6-month intervals, from 0 months and analyzed by age group. RESULTS: Seventy five percent of children were diagnosed as bronchial asthma. Children under 12-months showed sensitization to food allergens, such as egg white (13.3%) and cow's milk (3.3%), and no sensitization to inhaled allergens. However, house dust mite (HDM) and JCP sensitization increased significantly in children 1 to 2 year of age (HDM; 7.7-32.1%, JCP; 3.9-17.9%) and both sensitization increased to most frequent in children over 36 months of age. JCP sensitization was also frequently detected in children with HDM sensitization (47.1%). CONCLUSION: Sensitization to inhaled allergens was significantly increased in Japanese recurrent wheezers over 12 months of age and sensitization to HDM and JCP increased to most frequent over 36 months of age. JCP sensitization was established from early childhood and detected frequently in Japanese recurrent wheezers under 60 months of age. These characteristics are the same with HDM sensitization.

Temporal effects of Notch signaling and potential cooperation with multiple downstream effectors on adenohypophysis cell specification in zebrafish.

The adenohypophysis (AH) consists of six distinct types of hormone-secreting cells. In zebrafish, although proper differentiation of all AH cell types has been shown to require Notch signaling within a period of 14-16 h postfertilization (hpf), the mechanisms underlying this process remain to be elucidated. Herein, we observed using the Notch inhibitor dibenzazepine (DBZ) that Notch signaling also contributed to AH cell specification beyond 16 hpf. Specification of distinct cell types was perturbed by DBZ treatment for different time frames, suggesting that AH cells are specified by Notch-dependent and cell-type-specific mechanisms. We also found that two hes-family genes, her4.1 and hey1, were expressed in the developing AH under the influence of Notch signaling. her4.1 knockdown reduced expression of proopiomelanocortin a (pomca), growth hormone (gh), and prolactin, whereas hey1 was responsible only for gh expression. Simultaneous loss of both Her4.1 and Hey1 produced milder phenotypes than that of DBZ-treated embryos. Moreover, DBZ treatment from 18 hpf led to a significant down-regulation of both gh and pomca genes only when combined with injection of a subthreshold level of her4.1-morpholino. These observations suggest that multiple downstream effectors, including Her4.1 and Hey1, mediate Notch signaling during AH cell specification.

Cell-Surface MMP-9 Protein Is a Novel Functional Marker to Identify and Separate Proangiogenic Cells from Early Endothelial Progenitor Cells Derived from CD133(+) Cells.

To develop cell therapies for ischemic diseases, endothelial progenitor cells (EPCs) have been expected to play a pivotal role in vascular regeneration. It is desirable to use a molecular marker that is related to the function of the cells. Here, a quantitative polymerase chain reaction array revealed that early EPCs derived from CD133(+) cells exhibited significant expression of MMP-9. Some populations of early EPCs expressed MMP-9 on the cell surface and others did not. We also attempted to separate the proangiogenic fraction from early EPCs derived from CD133(+) cells using a functional cell surface marker, and we then analyzed the MMP-9(+) and MMP-9(-) cell fractions. The MMP-9(+) cells not only revealed higher invasion ability but also produced a high amount of IL-8. Moreover, the stimulative effect of MMP-9(+) cells on angiogenesis in vitro and in vivo was prohibited by anti-IL-8 antibody. These data indicate that MMP-9 is one of the useful cell surface markers for the separation of angiogenic cells. Our treatment of early EPCs with hyaluronidase caused not only a downregulation of cell-surface MMP-9 but also a decrease in invasion ability, indicating that membrane-bound MMP-9, which is one of the useful markers for early EPCs, plays an important role in angiogenesis. Stem Cells 2016;34:1251-1262.

Development of helix-stabilized antimicrobial peptides composed of lysine and hydrophobic α,α-disubstituted α-amino acid residues.

Lysine-based amphipathic nonapeptides, including homochiral peptides [Ac-(l-Lys-l-Lys-Xaa)3-NH2 (Xaa=Gly, Ala, Aib, Ac5c, or Ac6c) and Ac-(d-Lys-d-Lys-Aib)3-NH2], a heterochiral peptide [Ac-(l-Lys-d-Lys-Aib)3-NH2], and a racemic mixture of diastereomeric peptides [Ac-(rac-Lys-rac-Lys-Aib)3-NH2] were designed and synthesized to investigate the relationship between their preferred secondary structures and their antimicrobial activity. Peptide 5, [Ac-(l-Lys-l-Lys-Ac6c)3-NH2] formed a stable α-helical structure and exhibited strong activity against Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa).

Histone H3 Lysine 27 Trimethylation Leads to Loss of Mesendodermal Competence During Gastrulation in Zebrafish Ectodermal Cells.

Previous studies in Xenopus have shown that forced expression of Nodal signaling can change ectodermal cells to a mesodermal fate by the early gastrula stage, suggesting mesodermal competence in early ectoderm cells. This mesodermal competence in ectodermal cells has been shown to be regulated at the level of nucleocytoplasmic localization of Smad2 in Xenopus. However, the regulation of mesodermal competence through epigenetic mechanisms has not been fully elucidated. Here, we used a constitutively active form of zebrafish Smad2 (Smad2ca) to overcome the inhibition of Nodal signaling via the nuclear exclusion of Smad2. While heat-shock-dependent expression of Smad2ca at 5 h post fertilization (hpf) induced ectopic expression of mesendodermal genes in zebrafish ectodermal cells, responsiveness to Smad2ca was lost by 7 hpf. Chromatin immunoprecipitation-quantitative PCR analyses revealed that in ectodermal cells, levels of H3K27me3, but not H3K9me3, at both transcriptional start site (TSS) and 3'-flanking regions of mesendodermal genes at 9 hpf were markedly higher than those at 5 hpf. In contrast to mesendodermal genes, the levels of H3K27me3 at the TSS, but not 3'-flanking regions, of ectodermal genes remained low in ectodermal cells even at 9 hpf. We also found that chemical inhibition of H3K27me3 modification was able to recover the mesendodermal competence in ectodermal cells at 7 hpf, but not at 10 hpf. Taken together, our results suggest that the mesendodermal competence in zebrafish ectodermal cells is restricted by multiple mechanisms, including upregulation of H3K27me3 levels at the TSS of mesendodermal genes during early gastrulation.

Nipbl and mediator cooperatively regulate gene expression to control limb development.

Haploinsufficiency for Nipbl, a cohesin loading protein, causes Cornelia de Lange Syndrome (CdLS), the most common "cohesinopathy". It has been proposed that the effects of Nipbl-haploinsufficiency result from disruption of long-range communication between DNA elements. Here we use zebrafish and mouse models of CdLS to examine how transcriptional changes caused by Nipbl deficiency give rise to limb defects, a common condition in individuals with CdLS. In the zebrafish pectoral fin (forelimb), knockdown of Nipbl expression led to size reductions and patterning defects that were preceded by dysregulated expression of key early limb development genes, including fgfs, shha, hand2 and multiple hox genes. In limb buds of Nipbl-haploinsufficient mice, transcriptome analysis revealed many similar gene expression changes, as well as altered expression of additional classes of genes that play roles in limb development. In both species, the pattern of dysregulation of hox-gene expression depended on genomic location within the Hox clusters. In view of studies suggesting that Nipbl colocalizes with the mediator complex, which facilitates enhancer-promoter communication, we also examined zebrafish deficient for the Med12 Mediator subunit, and found they resembled Nipbl-deficient fish in both morphology and gene expression. Moreover, combined partial reduction of both Nipbl and Med12 had a strongly synergistic effect, consistent with both molecules acting in a common pathway. In addition, three-dimensional fluorescent in situ hybridization revealed that Nipbl and Med12 are required to bring regions containing long-range enhancers into close proximity with the zebrafish hoxda cluster. These data demonstrate a crucial role for Nipbl in limb development, and support the view that its actions on multiple gene pathways result from its influence, together with Mediator, on regulation of long-range chromosomal interactions.

Mechanistic target of rapamycin complex 1 signaling regulates cell proliferation, cell survival, and differentiation in regenerating zebrafish fins.

BACKGROUND: The mechanistic target of rapamycin complex1 (mTORC1) signaling pathway has been implicated in functions of multicellular processes, including cell growth and metabolism. Although recent reports showed that many signaling pathways, including Activin, Bmp, Fgf, sonic hedgehog, Insulin-like growth factor (IGF), Notch, retinoic acid, and Wnt, are implicated in non-mammalian vertebrate regeneration, also known as epimorphic regeneration, mTORC1 function remains unknown. RESULTS: To investigate the role of mTORC1 signaling pathway in zebrafish caudal fin, we examined the activation and function of mTORC1 signaling using an antibody against phosphorylated S6 kinase and a specific inhibitor, rapamycin. mTORC1 signaling is activated in proliferative cells of intra-ray and wound epidermal cells before blastema formation, as well as in proliferative blastema cells, wound epidermal cells, and osteoblasts during regenerative outgrowth. Before blastema formation, proliferation of intra-ray and wound epidermal cells is suppressed, but cell death is not affected by mTORC1 signaling inhibition with rapamycin. Moreover, rapamycin treatment inhibits blastema and wound epidermal cell proliferation and survival during blastema formation and regenerative outgrowth, as well as osteoblast proliferation and differentiation during regenerative outgrowth. We further determined that mTORC1 signaling is regulated through IGF-1 receptor/phosphatidylinositol-3 kinase and Wnt pathways during fin regeneration. CONCLUSION: Taken together, our findings reveal that mTORC1 signaling regulates proliferation, survival, and differentiation of intra-ray cells, wound epidermis, blastema cells, and/or osteoblasts in various fin regeneration stages downstream of IGF and Wnt signaling pathways.

Effects of Non-Invasive Brain Stimulation for Degenerative Cerebellar Ataxia: A Systematic Review and Meta-Analysis.

BACKGROUND: This systematic review and meta-analysis aimed to assess the effectiveness of non-invasive brain stimulation (NIBS), including repetitive transcranial magnetic stimulation (rTMS) and transcranial electrical stimulation (tES), as a neurological intervention for degenerative cerebellar ataxia (DCA) based on preregistration (PROSPERO: CRD42023379192). OBJECTIVE: We aimed to explore clinical outcomes and examine the parameters associated with NIBS efficacy in DCA patients. METHODS: The PubMed, Cochrane Library, CHINAL, and PEDro databases were searched for relevant randomized controlled trials (RCTs). Data extraction, quality assessment, and heterogeneity analyses were conducted; the Grading, Recommendations, Assessment, Development, and Evaluation was used to assess the quality of evidence and a meta-analysis was performed. RESULTS: Seventeen RCTs that included 661 patients on the scale for assessment and rating of ataxia (SARA) and 606 patients on the International Cooperative Ataxia Rating Scale (ICARS) were included. These RCTs showed a serious risk of bias (RoB) and low certainty of evidence for both outcomes. NIBS significantly reduced SARA (MD = -2.49, [95% confidence interval: -3.34, -1.64]) and ICARS (-5.27 [-7.06, -3.47]); the subgroup analysis showed significant effects: rTMS and tES reduced both outcomes. However, there were no significant differences in the effects of rTMS and tES. Additional subgroup analysis indicated the impact of rTMS frequency and the total number of tES sessions on ataxia. CONCLUSION: Non-invasive brain stimulation may reduce ataxia in DCA patients, but the estimated effect size may change in future studies because the RoB was serious and the certainty of evidence was low, and the heterogeneity was high. To establish evidence for selecting NIBS methods and parameters, continued high-quality RCTs are required.

Fatigue assessment for back-support exoskeletons during repetitive lifting tasks.

Fatigue is a major cause of low back pain for workers in various fields, including industry and agriculture. It has a negative impact on workers' safety, decreases their productivity, and causes a reduction in their occupational career. An exoskeleton is expected to be a solution for reducing workers' fatigue. However, assessing the safety and effectiveness of exoskeletons, except for the direct measurement of electromyography (EMG) in the human body, is challenging in real-case scenarios. Recently, simulations have been widely used to estimate biomechanical variables. Thus, we aimed to develop a method that combines an exoskeleton model and human body simulation to evaluate the effects of exoskeletons on lumbar fatigue. The strength and tendency estimated using this method are similar to those obtained from EMG devices in symmetrical repetitive lifting tasks. In addition, this method can be used to predict and simulate fatigue after a recorded motion. Our findings will help guide manufacturers in designing their products.

Kudoa septempunctata invasion increases the permeability of human intestinal epithelial monolayer.

Kudoa septempunctata is a myxosporean parasite of Paralichthys olivaceus (olive flounder) and causes a foodborne illness that affects more than 100 cases in Japan each year. We previously reported that the consumption of raw olive flounder meat containing a high concentration of K. septempunctata spores induces transient but severe diarrhea and emesis through an unknown mechanism. Here, we demonstrate that K. septempunctata sporoplasm plays an important role in mediating the toxicity of K. septempunctata. When K. septempunctata spores were inoculated in Caco-2 human intestinal cells, K. septempunctata sporoplasms were released from spores, and they invaded the cells. Electron microscopic observations revealed that the sporoplasm invasion severely damaged the Caco-2 cells. The inoculation of K. septempunctata spores eliminated the transepithelial electrical resistance (TER) across the cell monolayer. Inhibiting the invasion of the sporoplasms prevented the observed loss in cell layer integrity, as illustrated by the rapid elimination of the TER. These results suggest that the invasion by sporoplasms severely damaged individual intestinal cells, resulting in a loss of cell monolayer integrity.

CHRNA1 and its correlated-myogenesis/cell cycle genes are prognosis-related markers of metastatic melanoma.

Nicotinic acetylcholine receptors (CHRNs) expression and their critical role in various types of cancer have been reported. However, it is still unclear which CHRNs and their associated genes play essential roles in metastasis in melanoma patients. Here, we performed bioinformatics analyses on publicly available bulk RNA sequencing (RNA-seq) data of patients with melanoma to identify the CHRNs highly expressed in metastatic melanoma. We found that CHRNA1 was highly expressed in metastatic melanoma samples compared to primary melanoma samples and was strongly associated with CHRNB1 and CHRNG. These muscle-type CHRNs (CHRNA1, CHRNB1, and CHRNG) were correlated with the ZEB1 and Rho/ROCK pathway-related genes in metastatic melanoma samples. Pairwise correlations and enrichment analyses revealed that CHRNA1 was significantly associated with myogenesis/muscle contraction and cell cycle genes. Kaplan-Meier curves illustrated the involvement of CHRNA1, four of its correlated genes (DES, FLNC, CDK1, and CDC20), and the myogenesis gene signature in the prognosis of melanoma patients. Following the bulk RNA-seq analysis, single-cell RNA-seq (scRNA-seq) analysis showed that the CHRNA1-expressing melanoma cells are primarily metastatic and had high expression levels of CHRNB1, CHRNG, and myogenesis/cell cycle-related genes. Our bioinformatics analyses of the bulk RNA-seq and scRNA-seq data of patients with melanoma revealed that CHRNA1 and its correlated myogenesis/cell-related cycle genes are critical prognosis-related markers of metastatic melanoma.