Association between Inter-atrial Septum Motion and Persistent Atrial Fibrillation Recurrence after Catheter Ablation

Article信州医学雑誌 69(4) : 189-201(2021)departmental bulletin pape

The Lifestyle of the Segmented Filamentous Bacterium: A Non-Culturable Gut-Associated Immunostimulating Microbe Inferred by Whole-Genome Sequencing

Numerous microbes inhabit the mammalian intestinal track and strongly impact host physiology; however, our understanding of this ecosystem remains limited owing to the high complexity of the microbial community and the presence of numerous non-culturable microbes. Segmented filamentous bacteria (SFBs), which are clostridia-related Gram-positive bacteria, are among such non-culturable populations and are well known for their unique morphology and tight attachment to intestinal epithelial cells. Recent studies have revealed that SFBs play crucial roles in the post-natal maturation of gut immune function, especially the induction of Th17 lymphocytes. Here, we report the complete genome sequence of mouse SFBs. The genome, which comprises a single circular chromosome of 1 620 005 bp, lacks genes for the biosynthesis of almost all amino acids, vitamins/cofactors and nucleotides, but contains a full set of genes for sporulation/germination and, unexpectedly, for chemotaxis/flagella-based motility. These findings suggest a triphasic lifestyle of the SFB, which comprises two types of vegetative (swimming and epicellular parasitic) phases and a dormant (spore) phase. Furthermore, SFBs encode four types of flagellin, three of which are recognized by Toll-like receptor 5 and could elicit the innate immune response. Our results reveal the non-culturability, lifestyle and immunostimulation mechanisms of SFBs and provide a genetic basis for the future development of the SFB cultivation and gene-manipulation techniques

チョウカン トランス ポーター オ ブンシ ヒョウテキ トシタ ジンシッカン チリョウホウ ノ カクリツ オ メザシテ

The understanding of intestinal function in chronic kidney disease（CKD）has been important elements in the clinical management of CKD with dietary and drug therapy. Numerous studies have indicated that CKD patients or model rats have enzymatic abnormalities and impairments of absorptive function in the small intestine. However, it has been still unclear how different of the intestinal function in CKD. In this study, we demonstrated the microarray analysis of global gene expression in intestine of adenine-induced CKD rat. DNA microarray analysis using Affymextrix rat gene chip revealed that CKD caused great changes in gene expression in the rat duodenum : about４００genes exhibited more than a two-fold change in expression level. Gene ontology analysis showed that a global regulation of genes by CKD involved in iron ion binding, alcoholic, organic acid and lipid metabolism. Furthermore, we found markedly changes of a number of intestinal transporters gene expression. These results suggest that CKD may alter some nutrient metabolism in the small intestine by modifying the expression of specific genes. The intestinal transcriptome database of CKD might be useful to develop the novel drugs or functional foods targeting several intestinal genes including transporters for the management of CKD

Esophageal metastasis of renal cell carcinoma resected by endoscopic submucosal dissection: a case report

Background: Esophageal metastasis of renal cell carcinoma (RCC) is extremely rare. We have described herein a case of a 59-year-old man with esophageal metastasis of RCC that was endoscopically resected.Case presentation: The case was a 59-year-old man who had undergone left nephrectomy for renal clear cell carcinoma 17 years ago and splenectomy for splenic metastasis 3 years ago. Esophagogastroduodenoscopy (EGD) performed 9 years ago revealed a small reddish elevated lesion with a smooth surface in the middle esophagus; this lesion increased in size 4 years ago. However, no biopsy was performed. The lesion continued to grow in size and was found to have become nodular during the present observation. Biopsy revealed clear cell carcinoma. Endoscopic ultrasound (EUS) revealed that the lesion had not invaded the submucosa, and contrast-enhanced computed tomog-raphy did not reveal any other metastasis. The lesion was successfully removed en bloc via endoscopic submucosal dissection (ESD). Pathologically, the tumor was detected in the subepithelium with focal infiltration of the muscularis mucosa. It consisted of monotonous cells with small nuclei and a clear cytoplasm. Immunohistological findings indi-cated that the tumor was a metastasis of RCC. The lateral and vertical margins were noted to be free.Conclusions: We have presented herein a case of esophageal metastasis of RCC that had progressed over 9 years and was then resected en bloc through endoscopic submucosal dissection

Vagus Nerve Stimulation with Mild Stimulation Intensity Exerts Anti-Inflammatory and Neuroprotective Effects in Parkinson's Disease Model Rats

Background: The major surgical treatment for Parkinson's disease (PD) is deep brain stimulation (DBS), but a less invasive treatment is desired. Vagus nerve stimulation (VNS) is a relatively safe treatment without cerebral invasiveness. In this study, we developed a wireless controllable electrical stimulator to examine the efficacy of VNS on PD model rats. Methods: Adult female Sprague-Dawley rats underwent placement of a cuff-type electrode and stimulator on the vagus nerve. Following which, 6-hydroxydopamine (6-OHDA) was administered into the left striatum to prepare a PD model. VNS was started immediately after 6-OHDA administration and continued for 14 days. We evaluated the therapeutic effects of VNS with behavioral and immunohistochemical outcome assays under different stimulation intensity (0.1, 0.25, 0.5 and 1 mA). Results: VNS with 0.25-0.5 mA intensity remarkably improved behavioral impairment, preserved dopamine neurons, reduced inflammatory glial cells, and increased noradrenergic neurons. On the other hand, VNS with 0.1 mA and 1 mA intensity did not display significant therapeutic efficacy. Conclusions: VNS with 0.25-0.5 mA intensity has anti-inflammatory and neuroprotective effects on PD model rats induced by 6-OHDA administration. In addition, we were able to confirm the practicality and effectiveness of the new experimental device

Long-Term Continuous Cervical Spinal Cord Stimulation Exerts Neuroprotective Effects in Experimental Parkinson's Disease

Background: Spinal cord stimulation (SCS) exerts neuroprotective effects in animal models of Parkinson’s disease (PD). Conventional stimulation techniques entail limited stimulation time and restricted movement of animals, warranting the need for optimizing the SCS regimen to address the progressive nature of the disease and to improve its clinical translation to PD patients. Objective: Recognizing the limitations of conventional stimulation, we now investigated the effects of continuous SCS in freely moving parkinsonian rats. Methods: We developed a small device that could deliver continuous SCS. At the start of the experiment, thirty female Sprague-Dawley rats received the dopamine (DA)-depleting neurotoxin, 6-hydroxydopamine, into the right striatum. The SCS device was fixed below the shoulder area of the back of the animal, and a line from this device was passed under the skin to an electrode that was then implanted epidurally over the dorsal column. The rats were divided into three groups: control, 8-h stimulation, and 24-h stimulation, and behaviorally tested then euthanized for immunohistochemical analysis. Results: The 8- and 24-h stimulation groups displayed significant behavioral improvement compared to the control group. Both SCS-stimulated groups exhibited significantly preserved tyrosine hydroxylase (TH)-positive fibers and neurons in the striatum and substantia nigra pars compacta (SNc), respectively, compared to the control group. Notably, the 24-h stimulation group showed significantly pronounced preservation of the striatal TH-positive fibers compared to the 8-h stimulation group. Moreover, the 24-h group demonstrated significantly reduced number of microglia in the striatum and SNc and increased laminin-positive area of the cerebral cortex compared to the control group. Conclusions: This study demonstrated the behavioral and histological benefits of continuous SCS in a time-dependent manner in freely moving PD animals, possibly mediated by anti-inflammatory and angiogenic mechanisms

Fibroblast growth factor 23 mediates the phosphaturic actions of cadmium

Phosphaturia has been documented following cadmium (Cd) exposure in both humans and experimental animals. The fibroblast growth factor 23 (FGF23)/klotho axis serves as an essential phosphate homeostasis pathway in the bone-kidney axis. In the present study, we investigated the effects of Cd on phosphate (Pi) homeostasis in mice. Following Cd injection into WT mice, plasma FGF23 concentration was significantly increased. Urinary Pi excretion levels were significantly higher in Cd-injected WT mice than in control group. Plasma Pi concentration decreased only slightly compared with control group. No change was observed in plasma parathyroid hormone and 1,25-dihydroxy vitamin D3 in both group of mice. We observed a decrease in phosphate transport activity and also decrease in expression of renal phosphate transporter SLC34A3 [NaPi-IIc/NPT2c], but not SLC34A1 [NaPi-IIa/NPT2a]. Furthermore, we examined the effect of Cd on Npt2c in Npt2a-knockout (KO) mice which expresses Npt2c as a major NaPi co-transporter. Injecting Cd to Npt2aKO mice induced significant increase in plasma FGF23 concentration and urinary Pi excretion levels. Furthermore, we observed a decrease in phosphate transport activity and renal Npt2c expression in Cd-injected Npt2a KO mice. The present study suggests that hypophosphatemia induced by Cd may be closely associated with the FGF23/klotho axis

Surgery in the Standing Position by a Surgeon with Achilles Tendon Rupture

Unexpected injuries can have a profound effect on a surgeonʼs performance and thus on patients and surgical departments. Here we describe a technique for performing surgery in the standing position, as done by a surgeon with an Achilles tendon rupture. During his prescribed 45-day non-weight-bearing period for the left ankle after surgery for an Achilles tendon rupture, the surgeon was able to participate in 15 surgeries as an operator or assistant, due to his use of a combination of injured-leg genuflection on a stool and a ʻSurgical Body Supportʼ device. Similarly injured surgeons may benefit from such support