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1.
Surg Today ; 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39196341

RESUMEN

PURPOSE: Lateral pelvic lymph node (LPLN) metastasis of rectal neuroendocrine tumors (NETs) is rare, with unknown oncological features. We investigated the oncological impact of LPLN metastasis in patients with rectal NETs. METHODS: This study included 214 patients with rectal NETs who underwent curative surgery. We evaluated their clinicopathological characteristics and short- and long-term outcomes. RESULTS: LPLN dissection was performed in 15 patients with LPLN swelling ≥ 7 mm (preoperative imaging); 12 patients had LPLN metastases, 6 of whom had LPLN metastases without mesorectal lymph node metastases (skip metastasis). The short-term outcomes were similar between the groups with and without LPLN dissection. The median follow-up period was 59.4 months, and patients with LPLN metastasis showed significantly shorter disease-free and overall survival rates than those without metastasis. Among 199 patients who did not undergo LPLN dissection, only 1 had LPLN recurrence. In a univariate analysis, tumor depth, tumor grade, and LPLN metastasis were associated with the overall survival. In the multivariate analysis, only LPLN metastasis was an independent predictor of the overall survival. CONCLUSIONS: LPLN metastasis is a poor prognostic factor for patients with rectal NETs. LPLN enlargement can be considered an indication for dissection, owing to its high rate of metastasis and associated poor prognosis.

2.
Tech Coloproctol ; 28(1): 110, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39150556

RESUMEN

BACKGROUND: Needlescopic surgery is a minimally invasive procedure that uses thin trocars with 3-mm diameter. We used Turnbull-Cutait pull-through and delayed coloanal anastomosis in needlescopic surgery to avoid diverting ileostomy during intersphincteric resection for low rectal cancer. In this study, we aim to assess the diverting ileostomy avoidance rate and technical safety of this "minimal skin incision and no stoma" procedure. METHODS: This single-center retrospective study was conducted at the Cancer Institute Hospital, a tertiary referral center in Japan. Between January 2017 and December 2020, 11 patients underwent needlescopic intersphincteric resection with diverting ileostomy (NSI group), and 19 patients underwent needlescopic intersphincteric resection with delayed coloanal anastomosis (NSD group) for low rectal cancer. Data regarding patient backgrounds and short-term outcomes, including diverting ileostomy avoidance rate, pathological results, and postoperative defecatory function, were compared between the groups. RESULTS: There were no statistically significant differences between the NSI and NSD groups with respect to patient background, operation time (239 min versus 220 min, p = 0.68), estimated blood loss (45 g versus 25 g, p = 0.29), R0 resection rate (100% versus 100%, p = 1.00), and length of postoperative hospital stay (16 days versus 17 days, p = 0.42). The diverting ileostomy avoidance rate was 94.4% in the NSD group. The LARS and Wexner scores 12 months after surgery were not significantly different between the two groups. CONCLUSIONS: Needlescopic intersphincteric resection and delayed coloanal anastomosis can be safely performed in selected patients with a high rate of diverting ileostomy avoidance and comparable short-term outcomes.


Asunto(s)
Canal Anal , Anastomosis Quirúrgica , Ileostomía , Neoplasias del Recto , Humanos , Neoplasias del Recto/cirugía , Masculino , Femenino , Estudios Retrospectivos , Anastomosis Quirúrgica/métodos , Anastomosis Quirúrgica/efectos adversos , Anciano , Persona de Mediana Edad , Canal Anal/cirugía , Ileostomía/métodos , Ileostomía/efectos adversos , Ileostomía/instrumentación , Resultado del Tratamiento , Colon/cirugía , Tempo Operativo , Proctectomía/métodos , Proctectomía/efectos adversos , Factores de Tiempo , Defecación , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/epidemiología , Anciano de 80 o más Años , Japón
3.
Tech Coloproctol ; 27(12): 1387-1392, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37358669

RESUMEN

PURPOSE: Stoma site marking is an important preoperative intervention for preventing various stoma-associated complications. In our institution, standardized stoma site marking is routinely performed before rectal cancer surgery with stoma creation, and various stoma-associated factors are recorded in the ostomy-record template. The present study investigated risk factors for stoma leakage. METHODS: Our stoma site marking is standardized so that it can be performed by non-stoma specialists. To identify risk factors of stoma leakage at 3 months after surgery, various preoperative factors associated with stoma site marking in our ostomy-record template were retrospectively analyzed in 519 patients who underwent rectal cancer surgery with stoma creation from 2015 to 2020. RESULTS: Stoma leakage was seen in 35 of the 519 patients (6.7%). The distance between the stoma site marking and the umbilicus was less than 60 mm in 27 of the 35 patients (77%) who experienced stoma leakage, so a distance of less than 60 mm was identified as an independent risk factor for stoma leakage. Aside from preoperative factors, stoma leakage was also caused by postoperative skin wrinkles or surgical scars near the stoma site in 8 of 35 patients (23%). CONCLUSION: Preoperative standardized stoma site marking is necessary to achieve reliable marking that is easy to perform. To reduce the risk of stoma leakage, a distance of 60 mm or more between the stoma site marking and the umbilicus is ideal, and surgeons need to contrive ways to keep surgical scars away from the stoma site.


Asunto(s)
Laparoscopía , Neoplasias del Recto , Procedimientos Quirúrgicos Robotizados , Estomas Quirúrgicos , Humanos , Estudios Retrospectivos , Cicatriz , Estomas Quirúrgicos/efectos adversos , Laparoscopía/efectos adversos , Neoplasias del Recto/cirugía , Estándares de Referencia
4.
J Dairy Sci ; 106(10): 6710-6722, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37211485

RESUMEN

Yogurt is made by fermenting milk with 2 lactic acid bacteria, Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus. To comprehensively understand the protocooperation mechanism between S. thermophilus and L. bulgaricus in yogurt fermentation, we examined 24 combinations of cocultures comprising 7 fast- or slow-acidifying S. thermophilus strains with 6 fast- or slow-acidifying L. bulgaricus strains. Furthermore, 3 NADH oxidase (Nox)-deficient mutants (Δnox) and one pyruvate formate-lyase deficient mutant (ΔpflB) of S. thermophilus were used to evaluate the factor that determines the acidification rate of S. thermophilus. The results revealed that the acidification rate of S. thermophilus monoculture determined the yogurt fermentation rates, despite the coexistence of L. bulgaricus, whose acidification rate was either fast or slow. Significant correlation was found between the acidification rate of S. thermophilus monoculture and the amount of formate production. Result using ΔpflB showed that the formate was indispensable for the acidification of S. thermophilus. Moreover, results of the Δnox experiments revealed that formate production required Nox activity, which not only regulated dissolved oxygen, but also the redox potential. The Nox provided the large decrease in redox potential required by pyruvate formate-lyase to produce formate. A highly significant correlation was found between formate accumulation and Nox activity in S. thermophilus. In conclusion, the formate production ability provided by the action of Nox activity determines the acidification rate of S. thermophilus, and consequently, regulates yogurt coculture fermentation.


Asunto(s)
Lactobacillus delbrueckii , Yogur , Animales , Yogur/microbiología , Streptococcus thermophilus/fisiología , NAD , Oxidorreductasas , Fermentación , Formiatos , Concentración de Iones de Hidrógeno
7.
Clin Exp Immunol ; 198(3): 416-429, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31429073

RESUMEN

Tumor necrosis factor (TNF) receptor-associated periodic syndrome (TRAPS) is an autoinflammatory disease that is caused by heterozygous mutations in the TNFRSF1A gene. Although more than 150 TNFRSF1A mutations have been reported to be associated with TRAPS phenotypes only a few, such as p.Thr79Met (T79M) and cysteine mutations, have been functionally analyzed. We identified two TRAPS patients in one family harboring a novel p.Gly87Val (G87V) mutation in addition to a p.Thr90Ile (T90I) mutation in TNFRSF1A. In this study, we examined the functional features of this novel G87V mutation. In-vitro analyses using mutant TNF receptor 1 (TNF-R1)-over-expressing cells demonstrated that this mutation alters the expression and function of TNF-R1 similar to that with the previously identified pathogenic T79M mutation. Specifically, cell surface expression of the mutant TNF-R1 in transfected cells was inhibited with both G87V and T79M mutations, whereas the T90I mutation did not affect this. Moreover, peripheral blood mononuclear cells (PBMCs) from TRAPS patients harboring the G87V and T90I mutations showed increased mitochondrial reactive oxygen species (ROS). Furthermore, the effect of various Toll-like receptor (TLR) ligands on inflammatory responses was explored, revealing that PBMCs from TRAPS patients are hyper-responsive to TLR-2 and TLR-4 ligands and that interleukin (IL)-8 and granulocyte-macrophage colony-stimulating factor (GM-CSF) are likely to be involved in the pathogenesis of TRAPS. These findings suggest that the newly identified G87V mutation is one of the causative mutations of TRAPS. Our findings based on unique TRAPS-associated mutations provide novel insight for clearer understanding of inflammatory responses, which would be basic findings of developing a new therapeutic and prophylactic approach to TRAPS.


Asunto(s)
Fiebre/genética , Predisposición Genética a la Enfermedad/genética , Enfermedades Autoinflamatorias Hereditarias/genética , Mutación Missense , Receptores Tipo I de Factores de Necrosis Tumoral/genética , Adulto , Anciano , Secuencia de Aminoácidos , Secuencia de Bases , Análisis Mutacional de ADN/métodos , Femenino , Fiebre/diagnóstico , Enfermedades Autoinflamatorias Hereditarias/diagnóstico , Humanos , Masculino , Linaje , Homología de Secuencia de Aminoácido
9.
Diabet Med ; 34(4): 586-589, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27859559

RESUMEN

AIM: To examine the contribution of the FUT2 gene and ABO blood type to the development of Type 1 diabetes in Japanese children. METHODS: We analysed FUT2 variants and ABO genotypes in a total of 531 Japanese children diagnosed with Type 1 diabetes and 448 control subjects. The possible association of FUT2 variants and ABO genotypes with the onset of Type 1 diabetes was statistically examined. RESULTS: The se2 genotype (c.385A>T) of the FUT2 gene was found to confer susceptibility to Type 1A diabetes in a recessive effects model [odds ratio for se2/se2, 1.68 (95% CI 1.20-2.35); corrected P value = 0.0075]. CONCLUSIONS: The FUT2 gene contributed to the development of Type 1 diabetes in the present cohort of Japanese children.


Asunto(s)
Diabetes Mellitus Tipo 1/genética , Fucosiltransferasas/genética , Sistema del Grupo Sanguíneo ABO/genética , Pueblo Asiatico/genética , Estudios de Casos y Controles , Predisposición Genética a la Enfermedad , Humanos , Japón , Galactósido 2-alfa-L-Fucosiltransferasa
10.
Diabet Med ; 33(12): 1717-1722, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27352912

RESUMEN

AIMS: The aim of this study was to clarify the significance of previously reported susceptibility variants in the development of autoimmune Type 1 diabetes in non-white children. Tested variants included rs2290400, which has been linked to Type 1 diabetes only in one study on white people. Haplotypes at 17q12-q21 encompassing rs2290400 are known to determine the susceptibility of early-onset asthma by affecting the expression of flanking genes. METHODS: We genotyped 63 variants in 428 Japanese people with childhood-onset autoimmune Type 1 diabetes and 457 individuals without diabetes. Possible association between variants and age at diabetes onset was examined using age-specific quantitative trait locus analysis and ordered-subset regression analysis. RESULTS: Ten variants, including rs2290400 in GSDMB, were more frequent among the people with Type 1 diabetes than those without diabetes. Of these, rs689 in INS and rs231775 in CTLA4 yielded particularly high odds ratios of 5.58 (corrected P value 0.001; 95% CI 2.15-14.47) and 1.64 (corrected P value 5.3 × 10-5 ; 95% CI 1.34-2.01), respectively. Age-specific effects on diabetes susceptibility were suggested for rs2290400; heterozygosity of the risk alleles was associated with relatively early onset of diabetes, and the allele was linked to the phenotype exclusively in the subgroup of age at onset ≤ 5.0 years. CONCLUSIONS: The results indicate that rs2290400 in GSDMB and polymorphisms in INS and CTLA4 are associated with the risk of Type 1 diabetes in Japanese children. Importantly, cis-regulatory haplotypes at 17q12-q21 encompassing rs2290400 probably determine the risk of autoimmune Type 1 diabetes predominantly in early childhood.


Asunto(s)
Cromosomas Humanos Par 17/genética , Diabetes Mellitus Tipo 1/genética , Haplotipos/genética , Polimorfismo de Nucleótido Simple/genética , Adolescente , Adulto , Edad de Inicio , Anciano , Alelos , Niño , Preescolar , Femenino , Frecuencia de los Genes/genética , Predisposición Genética a la Enfermedad/genética , Humanos , Lactante , Japón/etnología , Masculino , Persona de Mediana Edad , Adulto Joven
11.
Clin Genet ; 88(3): 261-6, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25171146

RESUMEN

Approximately 20% of Beckwith-Wiedemann syndrome (BWS) cases are caused by mosaic paternal uniparental disomy of chromosome 11 (pUPD11). Although pUPD11 is usually limited to the short arm of chromosome 11, a small minority of BWS cases show genome-wide mosaic pUPD (GWpUPD). These patients show variable clinical features depending on mosaic ratio, imprinting status of other chromosomes, and paternally inherited recessive mutations. To date, there have been no reports of a mosaic GWpUPD patient with an autosomal recessive disease caused by a paternally inherited recessive mutation. Here, we describe a patient concurrently showing the clinical features of BWS and autosomal recessive cystinuria. Genetic analyses revealed that the patient has mosaic GWpUPD and an inherited paternal homozygous mutation in SLC7A9. This is the first report indicating that a paternally inherited recessive mutation can cause an autosomal recessive disease in cases of GWpUPD mosaicism. Investigation into recessive mutations and the dysregulation of imprinting domains is critical in understanding precise clinical conditions of patients with mosaic GWpUPD.


Asunto(s)
Síndrome de Beckwith-Wiedemann/diagnóstico , Síndrome de Beckwith-Wiedemann/genética , Cistinuria/genética , Genes Recesivos , Disomía Uniparental , Sistemas de Transporte de Aminoácidos Básicos/genética , Sistemas de Transporte de Aminoácidos Neutros/genética , Femenino , Genotipo , Humanos , Lactante , Riñón/patología , Mutación , Polimorfismo de Nucleótido Simple , Ultrasonografía
12.
Free Radic Res ; 48(11): 1322-33, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25096805

RESUMEN

Previous studies have suggested that carbon monoxide (CO) poisoning stimulates cAMP production via purine P2Y11-like receptors in the rat striatum, activating cAMP signaling pathways, resulting in hydroxyl radical ((•)OH) production. Extracellular ATP was thought likely to trigger the cascade, but the present study has failed to demonstrate a clear increase in the extracellular ATP due to CO poisoning. The CO-induced (•)OH production was attenuated by the P2Y11 receptor antagonist NF157, in parallel with its abilities to suppress the CO-induced cAMP production. The (•)OH production was more strongly suppressed by a non-selective P2 receptor antagonist, PPADS, which had no effect on cAMP production. More selective antagonists toward the respective P2 receptors susceptible to PPADS, including NF279, had little or no effect on the CO-induced (•)OH production. The intrastriatal administration of exogenous ATP dose-dependently stimulated (•)OH production, which was dose-dependently antagonized by PPADS and NF279 but not by NF157. Exogenous GTP and CTP dose-dependently stimulated (•)OH production, though less potently. The GTP-induced (•)OH production was susceptible to both of NF279 and PPADS, but the CTP-induced (•)OH production was resistant to PPADS. The mechanism of (•)OH production may differ between CO poisoning and exogenous ATP, while multiple P2 receptors could participate in (•)OH production. The CO-induced (•)OH production was susceptible to the inhibition of NADPH oxidase, but not xanthine oxidase. Also, the NADPH oxidase inhibition suppressed (•)OH production induced by forskolin, a stimulator of intracellular cAMP formation. It is likely that (•)OH is produced by NADPH oxidase activation via cAMP signaling pathways during CO poisoning.


Asunto(s)
Adenosina Trifosfato/farmacología , Intoxicación por Monóxido de Carbono/fisiopatología , Cuerpo Estriado/metabolismo , Radical Hidroxilo/metabolismo , Antagonistas Purinérgicos/farmacología , Suramina/análogos & derivados , Animales , Cuerpo Estriado/efectos de los fármacos , Masculino , Microdiálisis , Ratas , Ratas Sprague-Dawley , Suramina/farmacología
13.
Leg Med (Tokyo) ; 16(2): 84-8, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24369859

RESUMEN

Anomalous origin of the right coronary artery from the pulmonary artery (ARCAPA) is a rare anomaly. It may contribute to myocardial ischemia or sudden death, although the lesion is usually asymptomatic. We report a sudden death case of a 58-year-old man with ARCAPA coexisting with severe atherosclerotic coronary artery disease. He had been healthy until he complained of chest pain, several days before death, despite the discovery of heart murmur in childhood and suspicion of valvular heart disease. The autopsy revealed not only typical findings of the right coronary anomaly with well-developed collateral circulations but also severe atherosclerotic lesions of the left coronary artery, and ischemic change of the myocardium in the left and right coronary arterial perfusion territory. In addition to the "coronary steal" phenomenon primarily caused by ARCAPA, the reduced flow of both coronary arteries and further increase of "coronary steal" due to atherosclerotic obstructive coronary disease might have contributed to the patient's death.


Asunto(s)
Enfermedad de la Arteria Coronaria/patología , Anomalías de los Vasos Coronarios/patología , Muerte Súbita/etiología , Arteria Pulmonar/anomalías , Circulación Colateral , Estenosis Coronaria/patología , Fibrosis , Ventrículos Cardíacos/patología , Humanos , Masculino , Persona de Mediana Edad , Arteria Pulmonar/patología
14.
Med Sci Law ; 54(1): 51-3, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24052003

RESUMEN

We report a case in which identification of a deceased individual was established using multiple lot numbers printed on a body implantable device. Autopsy of an unknown woman revealed an intramedullary nail inserted within her right femur. The device manufacturer was identified from the configuration of the intramedullary nail, and the "use history" was traced from lot numbers printed on the device's multiple parts. The deceased individual was thus identified as a woman who had attempted suicide by jumping from a height about a year previously and had been transported to a hospital and undergone surgery that included implantation of the intramedullary nail. The main factor contributing to the rapid identification was the manufacturer's and distributor's record of the use history (traceability) of the product, because of their accountability for purposes of quality control. A second contributing factor was multiple lot numbers, resulting in extremely low probability of the same combination of lot numbers being present in multiple individuals. This case confirmed the utility of multiple lot numbers of body implantable devices in forensic identification.


Asunto(s)
Clavos Ortopédicos , Etiquetado de Productos , Adulto , Femenino , Fémur/lesiones , Fémur/cirugía , Patologia Forense , Fijación Intramedular de Fracturas/instrumentación , Humanos
15.
Endoscopy ; 45(8): 627-34, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23807806

RESUMEN

BACKGROUND AND STUDY AIMS: Only a few large cohort studies have evaluated the efficacy and safety of endoscopic necrosectomy for infected walled-off pancreatic necrosis (WOPN). Therefore, a multicenter, large cohort study was conducted to evaluate the efficacy and safety of endoscopic necrosectomy and to examine the procedural details and follow-up after successful endoscopic necrosectomy. PATIENTS AND METHODS: A retrospective review was conducted in 16 leading Japanese institutions for patients who underwent endoscopic necrosectomy for infected WOPN between August 2005 and July 2011. The follow-up data were also reviewed to determine the long-term outcomes of the procedures. RESULTS: Of 57 patients, 43 (75 %) experienced successful resolution after a median of 5 sessions of endoscopic necrosectomy and 21 days of treatment. Complications occurred in 19 patients (33 %) during the treatment period. Six patients died (11 %): two due to multiple organ failure and one patient each from air embolism, splenic aneurysm, hemorrhage from a Mallory - Weiss tear, and an unknown cause. Of 43 patients with successful endoscopic necrosectomy, recurrent cavity formation was observed in three patients during a median follow-up period of 27 months. CONCLUSIONS: Endoscopic necrosectomy can be an effective technique for infected WOPN and requires a relatively short treatment period. However, serious complications can arise, including death. Therefore, patients should be carefully selected, and knowledgeable, skilled, and experienced operators should perform the procedure. Further research into safer technologies is required in order to reduce the associated morbidity and mortality.


Asunto(s)
Endoscopía del Sistema Digestivo , Páncreas/patología , Páncreas/cirugía , Enfermedades Pancreáticas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Drenaje , Endoscopía del Sistema Digestivo/efectos adversos , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Necrosis/microbiología , Necrosis/cirugía , Recurrencia , Estudios Retrospectivos , Stents , Irrigación Terapéutica , Adulto Joven
16.
Endoscopy ; 45(5): 362-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23616126

RESUMEN

BACKGROUND AND STUDY AIMS: No prospective comparison of endoscopic ultrasonography-guided direct celiac ganglia neurolysis (EUS - CGN) vs. EUS-guided celiac plexus neurolysis (EUS - CPN) has been reported. The aim of the current study was to compare the effectiveness of EUS - CGN and EUS - CPN in providing pain relief from upper abdominal cancer pain in a multicenter randomized controlled trial. PATIENTS AND METHODS: Patients with upper abdominal cancer pain were randomly assigned to treatment using either EUS - CGN or EUS - CPN. Evaluation was performed at Day 7 postoperatively using a pain scale of 0 to 10. Patients for whom pain decreased to ≤ 3 were considered to have a positive response, and those experiencing a decrease in pain to ≤ 1 were considered to be completely responsive. Comparison between the two groups was performed using intention-to-treat analysis. The primary endpoint was the difference in treatment response rates between EUS - CGN and EUS - CPN at postoperative Day 7. Secondary endpoints included differences in complete response rates, pain scores, duration of pain relief, and incidence of adverse effects. RESULTS: A total of 34 patients were assigned to each group. Visualization of ganglia was possible in 30 cases (88 %) in the EUS - CGN group. The positive response rate was significantly higher in the EUS - CGN group (73.5 %) than in the EUS - CPN group (45.5 %; P = 0.026). The complete response rate was also significantly higher in the EUS - CGN group (50.0 %) than in the EUS - CPN group (18.2 %; P = 0.010). There was no difference in adverse events or duration of pain relief between the two groups. CONCLUSIONS: EUS - CGN is significantly superior to conventional EUS - CPN in cancer pain relief. CLINICAL TRIAL REGISTRATION: http://www.umin.ac.jp/ctr/index.htm (ID: UMIN-000002536).


Asunto(s)
Dolor Abdominal/terapia , Bloqueo Nervioso Autónomo/métodos , Plexo Celíaco , Ganglios Simpáticos , Manejo del Dolor/métodos , Neoplasias Pancreáticas/complicaciones , Dolor Abdominal/etiología , Anciano , Anciano de 80 o más Años , Anestésicos Locales , Bupivacaína , Endosonografía , Etanol/uso terapéutico , Femenino , Humanos , Análisis de Intención de Tratar , Masculino , Persona de Mediana Edad , Ultrasonografía Intervencional
17.
Eur Surg Res ; 47(4): 248-53, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22067527

RESUMEN

BACKGROUND: Sodium hyaluronate/carboxymethylcellulose (HA/CMC) is difficult to use in a moist environment because of its susceptibility to moisture. METHODS: We developed the three-layered nDM-14R membrane. The surface layers are composed of 1-lactide, glycolide and e-caprolactone copolymers. HA/CMC and nDM-14R were used in all these studies. (1) The central region of 1 × 10 cm specimens (n = 5) was moistened for 0, 5, 10, 20, 30 or 60 s, after which the tensile strength was determined; (2) one side of specimens of 1 × 10 cm (n = 5) was moistened with agar gel for 5, 10, 15 or 30 s, after which the adhesion strength was determined, and (3) Rat cecum (n = 10) was scratched, 3 × 3 cm specimens were placed on the scratched area, and adhesions were evaluated on postoperative day 14. RESULTS AND CONCLUSION: (1) The tensile strength of nDM-14R after contact for 10-30 s was greater than that of HA/CMC. (2) The adhesive strength of HA/CMC after contact for 5-10 s was greater than that of nDM-14R. (3) Adhesion scores in treatment groups were significantly lower than in the control group. The results suggest that nDM-14R has the same antiadhesive effect and allows easier placement under moist conditions than HA/CMC.


Asunto(s)
Membranas Artificiales , Complicaciones Posoperatorias/prevención & control , Adherencias Tisulares/prevención & control , Animales , Ensayo de Materiales , Ratas , Solubilidad , Resistencia a la Tracción
18.
Endoscopy ; 43(12): 1070-5, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21971925

RESUMEN

BACKGROUND AND STUDY AIMS: Recent studies have evaluated the efficacy of peroral cholangioscopy (POCS) for diagnosis of biliary diseases. In order to obtain clear images with POCS, saline irrigation, which is performed to replace yellow bile, is carried out for an extended duration. The aim of this study was to evaluate the feasibility of replacing saline irrigation with CO2 insufflation during POCS. PATIENTS AND METHODS: A total of 36 patients who had bile duct lesions and were due to undergo POCS were enrolled in the study. Of these patients, 18 underwent POCS using saline irrigation followed by CO2 insufflation, and 18 patients underwent the reverse approach. The two methods were compared with regard to the time required to obtain a clear endoscopic image and the quality of the images. RESULTS: The median time required to obtain a clear endoscopic image using CO2 insufflation (5.0 min) was significantly shorter than that required for saline irrigation (22.5 min; P < 0.001). The quality of the endoscopic images obtained was similar in 27 cases. However, CO2 insufflation provided better images in four cases that showed an abundance of mucin or biliary sludge, and saline irrigation was superior to CO2 insufflation in five cases that showed severe stricture with bleeding and tall papillary lesions. CONCLUSIONS: CO2 insufflation during POCS can reduce procedure time and simplify cholangioscopy. The overall image quality was similar to that obtained with conventional saline irrigation.


Asunto(s)
Enfermedades de los Conductos Biliares/diagnóstico , Conductos Biliares , Dióxido de Carbono/administración & dosificación , Endoscopía del Sistema Digestivo , Cloruro de Sodio/administración & dosificación , Grabación en Video , Anciano , Femenino , Humanos , Insuflación , Masculino , Persona de Mediana Edad , Irrigación Terapéutica
19.
Science ; 333(6046): 1119-21, 2011 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-21868669

RESUMEN

A single grain (~3 micrograms) returned by the Hayabusa spacecraft was analyzed by neutron activation analysis. This grain is mainly composed of olivine with minor amounts of plagioclase, troilite, and metal. Our results establish that the Itokawa sample has similar chemical characteristics (iron/scandium and nickel/cobalt ratios) to chondrites, confirming that this grain is extraterrestrial in origin and has primitive chemical compositions. Estimated iridium/nickel and iridium/cobalt ratios for metal in the Itokawa samples are about five times lower than CI carbonaceous chondrite values. A similar depletion of iridium was observed in chondrule metals of ordinary chondrites. These metals must have condensed from the nebular where refractory siderophile elements already condensed and were segregated.

20.
Science ; 333(6046): 1121-5, 2011 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-21868670

RESUMEN

The reflectance spectra of the most abundant meteorites, ordinary chondrites, are different from those of the abundant S-type (mnemonic for siliceous) asteroids. This discrepancy has been thought to be due to space weathering, which is an alteration of the surfaces of airless bodies exposed to the space environment. Here we report evidence of space weathering on particles returned from the S-type asteroid 25143 Itokawa by the Hayabusa spacecraft. Surface modification was found in 5 out of 10 particles, which varies depending on mineral species. Sulfur-bearing Fe-rich nanoparticles exist in a thin (5 to 15 nanometers) surface layer on olivine, low-Ca pyroxene, and plagioclase, which is suggestive of vapor deposition. Sulfur-free Fe-rich nanoparticles exist deeper inside (<60 nanometers) ferromagnesian silicates. Their texture suggests formation by metamictization and in situ reduction of Fe(2+).

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