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1.
Nat Commun ; 15(1): 4514, 2024 May 27.
Article de Anglais | MEDLINE | ID: mdl-38802491

RÉSUMÉ

Knowledge on the distribution and dynamics of glycosylation enzymes in the Golgi is essential for better understanding this modification. Here, using a combination of CRISPR/Cas9 knockin technology and super-resolution microscopy, we show that the Golgi complex is assembled by a number of small 'Golgi units' that have 1-3 µm in diameter. Each Golgi unit contains small domains of glycosylation enzymes which we call 'zones'. The zones of N- and O-glycosylation enzymes are colocalised. However, they are less colocalised with the zones of a glycosaminoglycan synthesizing enzyme. Golgi units change shapes dynamically and the zones of glycosylation enzymes rapidly move near the rim of the unit. Photobleaching analysis indicates that a glycosaminoglycan synthesizing enzyme moves between units. Depletion of giantin dissociates units and prevents the movement of glycosaminoglycan synthesizing enzymes, which leads to insufficient glycosaminoglycan synthesis. Thus, we show the structure-function relationship of the Golgi and its implications in human pathogenesis.


Sujet(s)
Glycosaminoglycanes , Appareil de Golgi , Appareil de Golgi/métabolisme , Glycosylation , Humains , Glycosaminoglycanes/métabolisme , Cellules HeLa , Systèmes CRISPR-Cas , Protéines membranaires/métabolisme , Protéines membranaires/génétique , Protéines de la matrice Golgienne
2.
Sci Rep ; 13(1): 5393, 2023 04 03.
Article de Anglais | MEDLINE | ID: mdl-37012350

RÉSUMÉ

Seasonal influenza outbreaks remain an important public health concern, causing large numbers of hospitalizations and deaths among high-risk groups. Understanding the dynamics of individual transmission is crucial to design effective control measures and ultimately reduce the burden caused by influenza outbreaks. In this study, we analyzed surveillance data from Kamigoto Island, Japan, a semi-isolated island population, to identify the drivers of influenza transmission during outbreaks. We used rapid influenza diagnostic test (RDT)-confirmed surveillance data from Kamigoto island, Japan and estimated age-specific influenza relative illness ratios (RIRs) over eight epidemic seasons (2010/11 to 2017/18). We reconstructed the probabilistic transmission trees (i.e., a network of who-infected-whom) using Bayesian inference with Markov-chain Monte Carlo method and then performed a negative binomial regression on the inferred transmission trees to identify the factors associated with onwards transmission risk. Pre-school and school-aged children were most at risk of getting infected with influenza, with RIRs values consistently above one. The maximal RIR values were 5.99 (95% CI 5.23, 6.78) in the 7-12 aged-group and 5.68 (95%CI 4.59, 6.99) in the 4-6 aged-group in 2011/12. The transmission tree reconstruction suggested that the number of imported cases were consistently higher in the most populated and busy districts (Tainoura-go and Arikawa-go) ranged from 10-20 to 30-36 imported cases per season. The number of secondary cases generated by each case were also higher in these districts, which had the highest individual reproduction number (Reff: 1.2-1.7) across the seasons. Across all inferred transmission trees, the regression analysis showed that cases reported in districts with lower local vaccination coverage (incidence rate ratio IRR = 1.45 (95% CI 1.02, 2.05)) or higher number of inhabitants (IRR = 2.00 (95% CI 1.89, 2.12)) caused more secondary transmissions. Being younger than 18 years old (IRR = 1.38 (95%CI 1.21, 1.57) among 4-6 years old and 1.45 (95% CI 1.33, 1.59) 7-12 years old) and infection with influenza type A (type B IRR = 0.83 (95% CI 0.77, 0.90)) were also associated with higher numbers of onwards transmissions. However, conditional on being infected, we did not find any association between individual vaccination status and onwards transmissibility. Our study showed the importance of focusing public health efforts on achieving high vaccine coverage throughout the island, especially in more populated districts. The strong association between local vaccine coverage (including neighboring regions), and the risk of transmission indicate the importance of achieving homogeneously high vaccine coverage. The individual vaccine status may not prevent onwards transmission, though it may reduce the severity of infection.


Sujet(s)
Vaccins antigrippaux , Grippe humaine , Enfant , Enfant d'âge préscolaire , Humains , Sujet âgé , Adolescent , Grippe humaine/épidémiologie , Grippe humaine/prévention et contrôle , Saisons , Théorème de Bayes , Vaccination
3.
Surg Endosc ; 37(8): 5931-5942, 2023 08.
Article de Anglais | MEDLINE | ID: mdl-37076615

RÉSUMÉ

BACKGROUND: The transorally inserted anvil (OrVil™) is frequently selected for esophagojejunostomy after laparoscopic total gastrectomy (LTG) because of its versatility. During anastomosis with OrVil™, the double stapling technique (DST) or hemi-double stapling technique (HDST) can be selected by overlapping the linear stapler and the circular stapler. However, no studies have reported the differences between the methods and their clinical significance. METHODS: A randomized controlled clinical trial with a parallel assignment and single-blind outcomes assessment analysis was conducted. Patients with gastric cancer eligible for LTG who met the selection criteria were randomized. Preoperative characteristics and perioperative and postoperative outcomes were compared between the DST and HDST. The primary endpoint was an anastomosis-related complication, and the secondary endpoints were perioperative outcomes and postoperative complications, excluding anastomosis-related complications. RESULTS: Thirty patients with gastric cancer were eligible and randomized. LTG and esophagojejunostomy were successfully performed in all patients, without conversion to laparotomy. Preoperative characteristics, excluding preoperative chemotherapy, were not significantly different between the two groups. One anastomotic leakage of Clavien-Dindo classification grade ≥ IIIa was observed in the DST, although no significant difference was found between the two groups (6.6% vs. 0%, P = 0.30). In the HDST, one case of anastomotic stricture required endoscopic balloon dilation. No significant differences were found in operative time, whereas the anastomosis time was significantly shorter in the HDST than in the DST (47.5 ± 15.8 vs. 38.2 ± 8.8 min, P = 0.028). Except for anastomosis-related complications, postoperative complications (P = 0.282) and postoperative hospital stay for the DST and HDST were not significantly different. CONCLUSIONS: No superiority was found between the DST and HDST with OrVil™ in esophagojejunostomy of LTG for gastric cancer with respect to postoperative complications, whereas the HDST may be preferable in terms of the simplicity of the surgical technique.


Sujet(s)
Laparoscopie , Tumeurs de l'estomac , Humains , Oesophage/chirurgie , Tumeurs de l'estomac/chirurgie , Tumeurs de l'estomac/complications , Méthode en simple aveugle , Agrafage chirurgical/méthodes , Laparoscopie/méthodes , Anastomose chirurgicale/méthodes , Gastrectomie/méthodes , Complications postopératoires/épidémiologie , Complications postopératoires/étiologie , Complications postopératoires/chirurgie
4.
Blood Adv ; 7(14): 3382-3394, 2023 07 25.
Article de Anglais | MEDLINE | ID: mdl-37042948

RÉSUMÉ

Cell polarity, the asymmetric distribution of proteins and organelles, is permanently or transiently established in various cell types and plays an important role in many physiological events. epidermal growth factor receptor substrate 15 homology domain-binding protein 1-like 1 (EHBP1L1) is an adapter protein that is localized on recycling endosomes and regulates apical-directed transport in polarized epithelial cells. However, the role of EHBP1L1 in nonepithelial cells, remains unknown. Here, Ehbp1l1-/- mice showed impaired erythroblast enucleation. Further analyses showed that nuclear polarization before enucleation was impaired in Ehbp1l1-/- erythroblasts. It was also revealed that EHBP1L1 interactors Rab10, Bin1, and dynamin were involved in erythroblast enucleation. In addition, Ehbp1l1-/- erythrocytes exhibited stomatocytic morphology and dehydration. These defects in erythroid cells culminated in early postnatal anemic lethality in Ehbp1l1-/- mice. Moreover, we found the mislocalization of nuclei and mitochondria in the skeletal muscle cells of Ehbp1l1-/- mice, as observed in patients with centronuclear myopathy with genetic mutations in Bin1 or dynamin 2. Taken together, our findings indicate that the Rab8/10-EHBP1L1-Bin1-dynamin axis plays an important role in multiple cell polarity systems in epithelial and nonepithelial cells.


Sujet(s)
Noyau de la cellule , Érythroblastes , Animaux , Souris , Protéines adaptatrices de la transduction du signal/génétique , Protéines adaptatrices de la transduction du signal/métabolisme , Noyau de la cellule/métabolisme , Dynamines/métabolisme , Érythroblastes/métabolisme , Érythrocytes/métabolisme
5.
J Cell Biol ; 220(1)2021 01 04.
Article de Anglais | MEDLINE | ID: mdl-33332551

RÉSUMÉ

In the developing brain, the polarity of neural progenitor cells, termed radial glial cells (RGCs), is important for neurogenesis. Intercellular adhesions, termed apical junctional complexes (AJCs), at the apical surface between RGCs are necessary for cell polarization. However, the mechanism by which AJCs are established remains unclear. Here, we show that a SNARE complex composed of SNAP23, VAMP8, and Syntaxin1B has crucial roles in AJC formation and RGC polarization. Central nervous system (CNS)-specific ablation of SNAP23 (NcKO) results in mice with severe hypoplasia of the neocortex and no hippocampus or cerebellum. In the developing NcKO brain, RGCs lose their polarity following the disruption of AJCs and exhibit reduced proliferation, increased differentiation, and increased apoptosis. SNAP23 and its partner SNAREs, VAMP8 and Syntaxin1B, are important for the localization of an AJC protein, N-cadherin, to the apical plasma membrane of RGCs. Altogether, SNARE-mediated localization of N-cadherin is essential for AJC formation and RGC polarization during brain development.


Sujet(s)
Encéphale/anatomopathologie , Polarité de la cellule , Névroglie/métabolisme , Névroglie/anatomopathologie , Protéines Qb-SNARE/déficit , Protéines Qc-SNARE/déficit , Animaux , Apoptose , Encéphale/physiopathologie , Cellules COS , Cadhérines/métabolisme , Différenciation cellulaire , Membrane cellulaire/métabolisme , Mouvement cellulaire , Noyau de la cellule/métabolisme , Cellules cultivées , Chlorocebus aethiops , Régulation négative , Démarche , Souris knockout , Neurogenèse , Neurones/anatomopathologie , Protéines Qb-SNARE/métabolisme , Protéines Qc-SNARE/métabolisme , Protéines R-SNARE , Récepteurs Notch/métabolisme , Transduction du signal , Syntaxine-1/métabolisme , Vésicules de transport/métabolisme , bêta-Caténine/métabolisme
6.
FASEB J ; 34(7): 9450-9465, 2020 07.
Article de Anglais | MEDLINE | ID: mdl-32496646

RÉSUMÉ

Intestinal epithelial cells (IECs) are not only responsible for the digestion and absorption of dietary substrates but also function as a first line of host defense against commensal and pathogenic luminal bacteria. Disruption of the epithelial layer causes malnutrition and enteritis. Rab6 is a small GTPase localized to the Golgi, where it regulates anterograde and retrograde transport by interacting with various effector proteins. Here, we generated mice with IEC-specific deletion of Rab6a (Rab6a∆IEC mice). While Rab6aΔIEC mice were born at the Mendelian ratio, they started to show IEC death, inflammation, and bleeding in the small intestine shortly after birth, and these changes culminated in early postnatal death. We further found massive lipid accumulation in the IECs of Rab6a∆IEC neonates. In contrast to Rab6a∆IEC neonates, knockout embryos did not show any of these abnormalities. Lipid accumulation and IEC death became evident when Rab6a∆IEC embryos were nursed by a foster mother, suggesting that dietary milk-derived lipids accumulated in Rab6a-deficient IECs and triggered IEC death. These results indicate that Rab6a plays a crucial role in regulating the lipid transport and maintaining tissue integrity.


Sujet(s)
Mort cellulaire , Cellules épithéliales/anatomopathologie , Inflammation/anatomopathologie , Intestin grêle/anatomopathologie , Lactation , Lipides/composition chimique , Protéines G rab/physiologie , Animaux , Cellules épithéliales/métabolisme , Femelle , Glycosylation , Inflammation/étiologie , Inflammation/métabolisme , Intestin grêle/métabolisme , Souris , Souris knockout
7.
Asian J Endosc Surg ; 13(2): 168-174, 2020 Apr.
Article de Anglais | MEDLINE | ID: mdl-31099183

RÉSUMÉ

INTRODUCTION: A transorally inserted anvil has been developed to facilitate the creation of a stapled anastomosis without the need for a purse string to secure the anvil into place during laparoscopic total gastrectomy (LTG). We describe a hemi-double stapling technique and application of a transorally inserted anvil for esophagojejunostomy during LTG, and we report the results of a retrospective study in which we examined the feasibility and safety of this method. We also describe the key technical details of the method. METHODS: Our anastomotic method has four chief features: (a) the esophagus is cut at a slant, and its left cut end is cut and punched for the hemi-double stapling technique; (b) the anvil and circular stapler are connected, placing the distal jejunum in cranial traction; (c) a single layer of sutures is used to correct dog-earing and overlapping, and these points are completely closed with Lembert sutures; and (d) the jejunal limb is fixed to the duodenal stump to prevent kinking of the jejunal limb and to decrease tension on the anastomosis. RESULTS: This method has been used in 53 patients thus far. LTG with Roux-en-Y reconstruction was successful in all patients, and there was no need for conversion to open surgery. The mean operative time was 313 minutes, and the mean blood loss was 106 mL. The mean postoperative hospital stay was 18 days. There was no anastomotic leakage or stenosis. CONCLUSION: Hemi-double stapling technique with a transorally inserted anvil for LTG can be performed safely and easily and safely. It can also product good outcomes.


Sujet(s)
Oesophagostomie/méthodes , Gastrectomie , Jéjunostomie/méthodes , Laparoscopie , Tumeurs de l'estomac/chirurgie , Agrafage chirurgical/méthodes , Sujet âgé , Anastomose chirurgicale , Études de faisabilité , Femelle , Humains , Mâle , Adulte d'âge moyen , Durée opératoire , Études rétrospectives , Agrafage chirurgical/instrumentation
8.
Gan To Kagaku Ryoho ; 46(5): 929-931, 2019 May.
Article de Japonais | MEDLINE | ID: mdl-31189818

RÉSUMÉ

A 68-year-old female patient presented with advanced gastric cancer and multiple hepatic tumors. Upper GI endoscopy showed a type 3 lesion in the posterior wall of the gastric body. Abdominal computed tomography revealed multiple liver metastases, and staging laparoscopy identified peritoneal dissemination. She was diagnosed with clinical Stage Ⅳ gastric cancer(cT3N2M1H1). She received 3 courses of combined chemotherapy containing S-1 and cisplatin. The therapeutic response was PR. We performed total gastrectomy with D2 lymph node dissection and splenectomy. Histopathological examination revealed no residual cancer cells, indicating pCR. She continued S-1 adjuvant chemotherapy and has remained free from recurrence for 18 months.


Sujet(s)
Protocoles de polychimiothérapie antinéoplasique/usage thérapeutique , Tumeurs de l'estomac , Sujet âgé , Cisplatine , Association médicamenteuse , Femelle , Gastrectomie , Humains , Récidive tumorale locale , Acide oxonique , Tégafur
9.
Scand J Gastroenterol ; 54(6): 787-792, 2019 Jun.
Article de Anglais | MEDLINE | ID: mdl-31125265

RÉSUMÉ

Objective: A new method of drug delivery via the small bowel, continuous infusion of levodopa-carbidopa intestinal gel (LCIG), for patients with advanced Parkinson's disease (PD) has been developed and shown to improve patients' quality of life. Levodopa is infused directly and continuously into the proximal jejunum via a percutaneous endoscopic transgastric jejunostomy (PEG-J) tube that is connected to a portable infusion pump. The aim of this study was to evaluate the safety and outcomes of our PEG-J technique performed in advance of LCIG therapy in patients with advanced PD. Material and methods: We reviewed the cases of 37 patients who underwent PEG-J for LCIG therapy at our hospital between November 2016 and May 2018. Pull-through percutaneous endoscopic gastrostomy (PEG) and gastropexy were performed in all patients. The J-tube was inserted through the PEG tube and placed beyond the ligament of Treitz endoscopically under fluoroscopic guidance. After two weeks, the gastropexy sutures were removed. Results: PEG-J with placement of the tube beyond the ligament of Treitz was successful in all 37 patients. Median procedure time was 26.4 min. Median hospital stay after the procedure was 16 days. Median follow-up with the PEG-J tube in place was 11 months. There were five procedure-related complications (13.5%) and 13 device-related complications (35.1%). There was no death related to the procedure. Conclusions: Our PEG-J technique can be performed safely in patients with advanced PD, and favorable outcomes have been achieved to date.


Sujet(s)
Carbidopa/administration et posologie , Endoscopie gastrointestinale/méthodes , Jéjunostomie , Lévodopa/administration et posologie , Maladie de Parkinson/traitement médicamenteux , Sujet âgé , Sujet âgé de 80 ans ou plus , Association médicamenteuse , Femelle , Gels/administration et posologie , Humains , Mâle , Adulte d'âge moyen , Qualité de vie , Études rétrospectives , Résultat thérapeutique
10.
Asian J Surg ; 42(1): 379-385, 2019 Jan.
Article de Anglais | MEDLINE | ID: mdl-29804711

RÉSUMÉ

BACKGROUND: Billroth Ⅰ (BⅠ) reconstruction and Roux-en-Y (RY) reconstruction are both commonly performed after distal gastrectomy (DG). We conducted a retrospective study to evaluate which is the better option. METHODS: Included in our study were 162 patients who, between April 2011 and October 2015, underwent DG followed by BⅠ reconstruction (n = 93) or RY reconstruction (n = 69). All patients were followed up for at least 1 year. We compared perioperative outcomes, postoperative complications, gastrointestinal (GI) symptoms, endoscopic findings, and nutritional status between the 2 groups of patients. RESULTS: Patient characteristics did not differ between the 2 groups, with the exception of the incidence of gastric body tumors, which was significantly higher in the RY group (73.9% vs. 19.4%; p < 0.001). Operation time was significantly longer in the RY reconstruction group (p < 0.001). There was no significant between-group difference in the grades of GI dysfunction (p = 0.122).The endoscopically determined RGB (Residual food, Gastritis, Bile reflux)scores were significantly better in the RY reconstruction group than in the BI reconstruction group (p = 0.027, p < 0.001,p < 0.001,respectively).There was also no significant between-group difference in the change (1-year postoperative value/preoperative value) in body weight, body mass index, serum albumin concentration, or total cholesterol concentration (p = 0.484,p = 0.613,p = 0.760,p = 0.890, respectively). CONCLUSIONS: RY reconstruction appears not to be advantageous over BⅠ reconstruction in terms of GI function or nutritional status 1 year after surgery. RY reconstruction does appear to be superior in terms of preventing bile reflux but takes more operation time.


Sujet(s)
Anastomose de Roux-en-Y/méthodes , Procédures de chirurgie digestive/méthodes , Gastrectomie/méthodes , /méthodes , Tumeurs de l'estomac/chirurgie , Sujet âgé , Reflux biliaire/prévention et contrôle , Femelle , Études de suivi , Humains , Mâle , Adulte d'âge moyen , État nutritionnel , Durée opératoire , Complications postopératoires/prévention et contrôle , Études rétrospectives , Facteurs temps , Résultat thérapeutique
11.
Esophagus ; 15(2): 88-94, 2018 04.
Article de Anglais | MEDLINE | ID: mdl-29892931

RÉSUMÉ

BACKGROUND: Esophagogastric anastomosis performed after esophagectomy is technically complex and often the source of postoperative complications. The best technique for this anastomosis remains a matter of debate. We describe a new all-stapled side-to-side anastomosis, which we refer to as triple-stapled quadrilateral anastomosis (TRIQ), that can be performed after minimally invasive surgery, and we report results of a retrospective evaluation of postoperative outcomes among the 60 patients in whom this anastomosis has been performed thus far. METHODS: The anastomosis is created by apposition of the posterior walls of the esophagus and stomach. A linear stapler is applied to create a V-shaped posterior anastomotic wall. The anterior wall is closed in a gentle chevron-like shape with the use of 2 separate linear staplers, resulting in a wide quadrilateral anastomosis. The anastomosis is then wrapped with a greater omentum flap. RESULTS: The patient group comprised 48 men and 12 women with a mean age of 67.8 years. Neoadjuvant chemotherapy was performed in 43 of these patients. Neither the thoracoscopic or laparoscopic procedure was converted to open surgery in any patient. The median operation time was 474 min (range 680-320 min). The intraoperative blood loss volume was 104.4 mL (range 240-30 mL). There were no anastomosis-related complications above Clavien-Dindo grade II. CONCLUSIONS: TRIQ can be performed easily and safely, and good short-term outcome can be expected.


Sujet(s)
Tumeurs de l'oesophage/chirurgie , Oesophage/chirurgie , Estomac/chirurgie , Agrafage chirurgical/méthodes , Sujet âgé , Anastomose chirurgicale/effets indésirables , Anastomose chirurgicale/méthodes , Perte sanguine peropératoire , Oesophagectomie , Femelle , Humains , Laparotomie , Mâle , Adulte d'âge moyen , Omentum/transplantation , Durée opératoire , Études rétrospectives , Lambeaux chirurgicaux , Thoracoscopie
12.
Surg Endosc ; 32(9): 4011-4016, 2018 09.
Article de Anglais | MEDLINE | ID: mdl-29915985

RÉSUMÉ

BACKGROUND: Billroth I reconstruction is a means of anastomosis that is widely performed after surgical resection for distal gastric cancer. Interest has grown in totally laparoscopic gastrectomy, and several methods for totally laparoscopic performance of Billroth I reconstruction have been reported. However, the methods are cumbersome, and postoperative complications such as twisting at the site of anastomosis and obstruction due to stenosis have arisen. We developed an augmented rectangle technique (ART) by which the anastomosis is created laparoscopically with the use of three automatic endoscopic linear staplers, and the resulting anastomotic opening is wide and less likely to become twisted or stenosed. The technical details of our ART-based Billroth I anastomosis are presented herein along with results of the procedure to date. METHODS: The technique was applied in 160 patients who underwent totally laparoscopic distal gastrectomy for gastric cancer between December 2013 and August 2017. Clinicopathological data, surgical data, and postoperative outcomes were analyzed. RESULTS: During surgery, there were no troubles associated with gastrointestinal reconstruction and there was no transition to laparotomy. There were no postoperative complications, including suture failure and stenosis, associated with the gastrointestinal reconstruction, and the average postoperative hospital stay was 12 days. CONCLUSION: Totally laparoscopic ART-based Billroth I reconstruction is both feasible and safe. We expect this technique to contribute to the spread of safe totally laparoscopic surgery for gastric cancer.


Sujet(s)
Gastrectomie/méthodes , Gastroentérostomie/méthodes , Laparoscopie/méthodes , Tumeurs de l'estomac/chirurgie , Sujet âgé , Femelle , Humains , Mâle
13.
Proc Natl Acad Sci U S A ; 113(40): E5886-E5895, 2016 10 04.
Article de Anglais | MEDLINE | ID: mdl-27651490

RÉSUMÉ

Unconventional mRNA splicing on the endoplasmic reticulum (ER) membrane is the sole conserved mechanism in eukaryotes to transmit information regarding misfolded protein accumulation to the nucleus to activate the stress response. In metazoans, the unspliced form of X-box-binding protein 1 (XBP1u) mRNA is recruited to membranes as a ribosome nascent chain (RNC) complex for efficient splicing. We previously reported that both hydrophobic (HR2) and translational pausing regions of XBP1u are important for the recruitment of its own mRNA to membranes. However, its precise location and the molecular mechanism of translocation are unclear. We show that XBP1u-RNC is specifically recruited to the ER membrane in an HR2- and translational pausing-dependent manner by immunostaining, fluorescent recovery after photobleaching, and biochemical analyses. Notably, translational pausing during XBP1u synthesis is indispensable for the recognition of HR2 by the signal recognition particle (SRP), resulting in efficient ER-specific targeting of the complex, similar to secretory protein targeting to the ER. On the ER, the XBP1u nascent chain is transferred from the SRP to the translocon; however, it cannot pass through the translocon or insert into the membrane. Therefore, our results support a noncanonical mechanism by which mRNA substrates are recruited to the ER for unconventional splicing.


Sujet(s)
Réticulum endoplasmique/métabolisme , Biosynthèse des protéines , Particule de reconnaissance du signal/métabolisme , Transduction du signal , Protéine-1 liant la boite X/génétique , Séquence d'acides aminés , Animaux , Cellules COS , Chlorocebus aethiops , Cellules HEK293 , Cellules HeLa , Humains , Membranes intracellulaires/métabolisme , Modèles biologiques , Signaux de localisation nucléaire/métabolisme , Liaison aux protéines , Transport des protéines , Épissage des ARN , ARN messager/génétique , ARN messager/métabolisme , Protéine-1 liant la boite X/composition chimique , Protéine-1 liant la boite X/métabolisme
14.
Microbiol Res ; 163(1): 63-72, 2008.
Article de Anglais | MEDLINE | ID: mdl-16697631

RÉSUMÉ

We have cloned and characterized spr1, a putative serine protease gene, from a nematode-trapping fungus, Monacrosporium megalosporum. The gene was present as a single copy in the genome. The predicted protein sequence of spr1 is homologous to the putative cuticle-degrading serine proteases PII and Azo1 from the nematode-trapping fungus, Arthrobotrys oligospora. In the 5' untranslated region near the initiation codon, consensus sequences to an AreA binding site, a well-known mediator of nitrogen metabolite repression in the fungus Aspergillus nidulans, a CreA binding site, a carbon response regulator in A. nidulans, and a PacC binding site, a transcription factor that responds to ambient pH signals in A. nidulans were found. However, spr1 was not regulated by carbon or nitrogen source, and exogenous protein did not induce expression of spr1. The transcription of the spr1 gene of this fungus was significantly affected by ambient pH. Based on RT-PCR, the product of the spr1 gene was not transcribed at pH 4, whereas under alkaline conditions such as pH 8 and 9, the spr1 gene was transcribed well. These results indicate that the spr1 gene is controlled only by a PacC homologue. Moreover, the expression profile of the spr1 gene corresponded with the pH-dependent physiology of this fungus.


Sujet(s)
Champignons/génétique , Régulation de l'expression des gènes fongiques , Nematoda/microbiologie , Serine endopeptidases/génétique , Séquence d'acides aminés , Animaux , Champignons/enzymologie , Gènes fongiques , Concentration en ions d'hydrogène , Données de séquences moléculaires , Pinus/parasitologie , Maladies des plantes/parasitologie
15.
J Neurosci ; 26(15): 4046-53, 2006 Apr 12.
Article de Anglais | MEDLINE | ID: mdl-16611821

RÉSUMÉ

Magnetoencephalographic (MEG) studies have revealed enhancement of neural activity of the N1m response of auditory evoked fields in long-term trained musicians, reflecting neuroplastic modification of the representation of the auditory cortex. In contrast, the amplitude of the P2 response of auditory evoked potentials is modified by musical experience, with no alteration of N1. Here, we performed a comprehensive MEG study using stimulation of successive musical-instrument tones to examine how the neural activities of different MEG responses are modified in long-term experienced musicians who commenced musical lessons at ages of approximately 5 years and had continued to practice. The dipole moment of the P2m response occurring at 160-180 ms was significantly enlarged in musicians compared with that in individuals who had not received musical lessons. The enlargement was found for the dipole moment of N1m occurring at 100-120 ms in a restricted condition but not for the moment of P1m at 50-60 ms. Furthermore, the dipole moment of P2m for successive stimuli, normalized by the moment for the first stimulus, was significantly larger for chord tones than single tones and was significantly larger in the musicians than controls. These results suggest that the P2m response is susceptible to be modified by musical training in a period of neural maturation, with a short refractory period of neural activity for the auditory input of composite tones. The P2m activity may be specialized to the processing of multifrequency sounds, such as musical timbre consisting of abundant harmonics.


Sujet(s)
Cortex auditif/physiologie , Encéphale/physiologie , Potentiels évoqués auditifs/physiologie , Magnétoencéphalographie/méthodes , Musique , Adulte , Humains , Perception sonore , Mâle , Temps de réaction , Localisation sonore
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