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61.
Chen Y Soto-Gutierrez A Navarro-Alvarez N Rivas-Carrillo JD Yamatsuji T Shirakawa Y Tanaka N Basma H Fox IJ Kobayashi N 《Cell transplantation》2006,15(10):865-871
Human embryonic stem (hES) cells have the ability to differentiate into a variety of different cell lineages and potentially provide a source of differentiated cells for many therapeutic uses. Here we investigated an efficient method of hepatic differentiation from hES cells. A human ES cell line, KhES-1, was used and maintained by a nonfeeder method. KhES-1 cells were cultured for 5 days in the presence of human activin A (50 ng/ml) and then treated with a deleted variant of hepatocyte growth factor (dHGF) at 0, 100, or 500 ng/ml for 7 days. The resultant cells were biologically analyzed. The expression of the endodermal genes SOX17 and FOXA2 increased in KhES-1 cells after activin A treatment. In contrast, Oct4, a self-renewal undifferentiated marker, decreased in a time-dependent manner in KhES-1 cells. Following a 7-day treatment of the resultant cells with dHGF, especially at 500 ng/ml, KhES-1 cells showed an expression of the hepatic makers albumin, AFP, and CK18. Transitional electron microscopy showed well-developed glycogen rosettes and a gap junction in KhES-1 cells treated with 500 ng/ml of dHGF. We developed an efficient method to differentiate KhES-1 cells into hepatocyte-like cells in vitro using 50 ng/ml of activin A and 500 ng/ml of dHGF. 相似文献
62.
Nicolás A Rotholtz Alejandro G Canelas Maximiliano E Bun Mariano Laporte Emmanuel E Sadava Natalia Ferrentino Sebastián A Guckenheimer 《World journal of gastrointestinal surgery》2016,8(4):308-314
AIM: To analyze the results of laparoscopic colectomy in complicated diverticular disease.METHODS: This was a retrospective cohort study conducted at an academic teaching hospital. Data were collected from a database established earlier, which comprise of all patients who underwent laparoscopic colectomy for diverticular disease between 2000 and 2013. The series was divided into two groups that were compared: Patients with complicated disease(abscess, perforation, fistula, or stenosis)(G1) and patients undergoing surgery for recurrent diverticulitis(G2). Recurrent diverticulitis was defined as two or more episodes of diverticulitis regardless of patient age. Data regarding patient demographics, comorbidities, prior abdominal operations, history of acute diverticulitis, classification of acute diverticulitis at index admission and intra and postoperative variables were extracted. Univariate analysis was performed in both groups.RESULTS: Two hundred and sixty patients were included: 28%(72 patients) belonged to G1 and 72%(188 patients) to G2. The mean age was 57(27-89) years. The average number of episodes of diverticulitis before surgery was 2.1(r 0-10); 43 patients had no previous inflammatory pathology. There were significant differences between the two groups with respect to conversion rate and hospital stay(G1 18% vs G2 3.2%, P = 0.001; G1: 4.7 d vs G2 3.3 d, P < 0.001). The anastomotic dehiscence rate was 2.3%, with no statistical difference between the groups(G1 2.7% vs G2 2.1%, P = 0.5). There were no differences in demographic data(body mass index, American Society of Anesthesiology and previous abdominal surgery), operative time and intraoperative and postoperative complications between the groups. The mortality rate was 0.38%(1 patient), represented by a death secondary to septic shock in G2.CONCLUSION: The results support that the laparoscopic approach in any kind of complicated diverticular disease can be performed with low morbidity and acceptable conversion rates when compared with patients undergoing laparoscopic surgery for recurrent diverticulitis. 相似文献
63.
Hans Peter Dietz Alejandro Pattillo Garnham Rodrigo Guzmán Rojas 《International urogynecology journal》2016,27(6):909-913
Introduction and hypothesis
Levator avulsion is a risk factor for female pelvic organ prolapse (POP) and recurrence after POP surgery. Imaging diagnosis requires the observation of an abnormal muscle insertion on tomographic ultrasound imaging (TUI). This study was designed to compare the diagnostic performance of the qualitative diagnosis (visual qualitative assessment) to measurement of the distance between muscle insertion and urethra [levator–urethra gap; (LUG)].Methods
This was a retrospective analysis of data obtained in a tertiary urogynecological unit. All patients presented with symptoms of pelvic floor dysfunction and underwent 4D translabial pelvic floor ultrasound (US), supine, and after voiding. Avulsion was defined qualitatively as abnormal muscle insertion and quantitatively as LUG ≥25 mm on at least three consecutive central axial plane slices, with one examiner using both methods. We examined the correlation between both methods and validated them against clinical prolapse, significant organ descent on US, and hiatal ballooning.Results
Between January and July 2013, 233 patients were seen, of whom 202 had complete volume data sets. The qualitative method diagnosed avulsion in 22 % and the quantitative method in 24.3 %. Agreement was good, with a kappa of 0.79 (0.70–0.87). Avulsion diagnosed by either method was associated with clinical and sonographic prolapse and hiatal ballooning, with odds ratios nonsignificantly higher for the quantitative method.Conclusion
Qualitative analysis of slices on TUI and a method using LUG measurement show good agreement for the diagnosis of avulsion. The LUG method is at least equally as valid in its capacity to predict significant prolapse on clinical examination and US, as well as ballooning of the levator hiatus.64.
Ratko Yurac Juan J. Zamorano Fernando Lira Diego Valiente Vicente Ballesteros Alejandro Urzúa 《European spine journal》2016,25(5):1403-1408
Purpose
A recurrent lumbar disc herniation (RLDH) is the most prevalent cause for new radicular pain after surgery for disc herniation-induced sciatica. Reported risk factors include age, gender and smoking, while its surgical treatment is associated to a higher rate of complications and costs. The purpose of this study is to identify factors that increase the risk of requiring surgical treatment for a first RLDH in workers’ compensation patients.Methods
Nested case–control: 109 patients operated for an RLDH (cases) between June 1st 1994 and May 31st 2011 (minimum follow-up 1 year) and 109 randomly selected patients operated for a first disc herniation with no recurrence during the study period (controls). Age, gender, smoking status, type of work and MRI characteristics of the index herniation were statistically evaluated as potential risk factors.Results
Patient’s age of less than 35 years (p = 0.001) and a subligamentous herniation (p < 0.05) at the time of the index surgery were identified as risk factors for requiring surgical treatment of a first RLDH. No statistical differences were observed between both groups regarding the other evaluated variables.Conclusion
A subligamentous disc herniation and patient’s age inferior to 35 years at the time of the first surgery are risk factors for requiring surgical treatment of a first RLDH among workers’ compensation patients.65.
Reduced mortality rate in patients with severe traumatic brain injury treated with brain tissue oxygen monitoring 总被引:10,自引:0,他引:10
Stiefel MF Spiotta A Gracias VH Garuffe AM Guillamondegui O Maloney-Wilensky E Bloom S Grady MS LeRoux PD 《Journal of neurosurgery》2005,103(5):805-811
OBJECT: An intracranial pressure (ICP) monitor, from which cerebral perfusion pressure (CPP) is estimated, is recommended in the care of severe traumatic brain injury (TBI). Nevertheless, optimal ICP and CPP management may not always prevent cerebral ischemia, which adversely influences patient outcome. The authors therefore determined whether the addition of a brain tissue oxygen tension (PO2) monitor in the treatment of TBI was associated with an improved patient outcome. METHODS: Patients with severe TBI (Glasgow Coma Scale [GCS] score < 8) who had been admitted to a Level I trauma center were evaluated as part of a prospective observational database. Patients treated with ICP and brain tissue PO2 monitoring were compared with historical controls matched for age, pathological features, admission GCS score, and Injury Severity Score who had undergone ICP monitoring alone. Therapy in both patient groups was aimed at maintaining an ICP less than 20 mm Hg and a CPP greater than 60 mm Hg. Among patients whose brain tissue PO2 was monitored, oxygenation was maintained at levels greater than 25 mm Hg. Twenty-five patients with a mean age of 44 +/- 14 years were treated using an ICP monitor alone. Twenty-eight patients with a mean age of 38 +/- 18 years underwent brain tissue PO2-directed care. The mean daily ICP and CPP levels were similar in each group. The mortality rate in patients treated using conventional ICP and CPP management was 44%. Patients who also underwent brain tissue PO2 monitoring had a significantly reduced mortality rate of 25% (p < 0.05). CONCLUSIONS: The use of both ICP and brain tissue PO2 monitors and therapy directed at brain tissue PO2 is associated with reduced patient death following severe TBI. 相似文献
66.
María Jesús Ladra Jesús P. Paredes Enrique Flores Lucía Martínez Yago Rojo Joaquín Potel Alejandro Beiras 《Cirugía espa?ola》2009,85(1):26-31
Introduction
The increasing aging of the population also increases the prevalence of symptomatic gallbladder diseases. It is important to analyse their surgical treatment in the elderly.Methods
All the laparoscopic cholecystectomies performed in our surgery department on patients aged 80 years-old or over from 1992 to 2007 were included in this study.Results
Laparoscopic cholecystectomy was performed on 133 patients 80 years-old and over, with 63% of them women, and an average age of 83.23 years. Biliary colic (29%) and acute pancreatitis (44%) were the main reasons for surgery. Associated diseases were found in 73% of them. Only 7.5% needed urgent surgery, even although 71% were admitted urgently. There were 13.5% conversions to open surgery, 17% morbidity and 2.3% mortality.Conclusions
Laparoscopic cholecystectomy can be recommended in symptomatic gallbladder disease in the elderly. 相似文献67.
Ramírez-Bollas J Padilla-Rosciano A Romero-Y Huesca A Lavín-Lozano AJ Medina-Castro JM Dubón-García E Turcios-Cadenas ER 《Cirugia y cirujanos》2005,73(3):217-221
Maffucci syndrome is a rare, congenital disease, which is associated with the appearance of multiple enchondromas (possibility of malignant transformation in 20 to 100%), soft tissue hemangiomas and other mesenchymatous injuries. Case 1 is a 33-year-old female who presented with multiple nodules predominantly in upper extremities. Upon examination, there was deformity in articulation and nodules on the hands, which were soft and moveable. There were bony shavings in the second and fourth fingers of the left hand (enchondromas and atypical cells associated with hemangioma esclerosante). Maffucci syndrome was diagnosed. Later, excision of subcutaneous nodules in superior extremities was performed along with excision of nodules in both hands and hypochondrium (enchondroma injuries of left hand and hypochondrium, hemangioma in right hand). There was dysarticulation of the second finger at the metacarpal level of the phalanges of the left hand (chondrosarcoma). The patient is being followed up currently. Case 2 is a 26-year-old female. The patient had a history of subcutaneous abdominal tumor, exostosis, nodules and nodule in right breast. Upon examination, a tumor was found in the right breast, exostosis of right tibia, injury to the right wrist and left thyroid nodule. A simple mastectomy and axillary dissection was performed (fibroadenoma to intracanalicular and 14 negative lymph nodes). Later, left thyroidectomy and lumpectomy in right wrist were performed (hyperplasia to nodular thyroid and hemangioma cavernous). There was injury in the carpus of the right hand and elbow (hemangioma cavernous and synovial tissue with fibrosis and enchondroma). A diagnosis was made of Marffucci syndrome associated with mesenchymatous tumors. The patient was in poor general health and did not survive this hospitalization. 相似文献
68.
69.
In order to study acute retinal toxicity of intravitreal triamcinolone acetonide (TA) at high doses in an animal model, thirty New Zealand albino rabbits were injected with intravitreal TA. The animals were divided in five groups: Group 1 received an intravitreal injection of 0.1 mL balanced salt solution; Group 2, 0.1 mL of the solvent (0.99 mg of benzyl alcohol); Group 3, received 4 mg/0.1 mL TA; Group 4, 20mg/0.1 mL TA; and Group 5, 30 mg/0.1 mL TA. A standard light and dark adapted electroretinogram (ERG) was obtained prior and 28 days after the injection. The animals were sacrificed 28 days after the injection and the eyes were enucleated and examined by electron (EM) and light microscopy (LM) using hematoxylin-eosin, Nissl fluorescent, and immunohistochemistry (glial fibrillary acidic protein). No statistically significant differences in ERG before and 28 days after the injection were found. LM and EM did not show retinal damage in any animal. One eye developed bacterial endophthalmitis 14 days after the injection. Intravitreal TA up to 30 mg does not seem to have acute toxic effects on the function (ERG) or the structure (LM, EM) of the retina of albino rabbits. 相似文献
70.
Aleman TS Cideciyan AV Sumaroka A Schwartz SB Roman AJ Windsor EA Steinberg JD Branham K Othman M Swaroop A Jacobson SG 《Investigative ophthalmology & visual science》2007,48(10):4759-4765
PURPOSE: To investigate in vivo the retinal microstructure in X-linked retinitis pigmentosa (XLRP) caused by RPGR mutations as a prelude to treatment initiatives for this common form of RP. METHODS: Patients with RPGR-XLRP (n = 12; age range, 10-56 years) were studied by optical coherence tomography (OCT) in a wide region of central retina. Overall retinal thickness and outer nuclear layer (ONL) and inner retinal parameters across horizontal and vertical meridians were analyzed and compared. RESULTS: Retinal architecture of all patients with RPGR mutations was abnormal. At the fovea in younger patients, the ONL could be normal; but, at increasing eccentricities, there was a loss of photoreceptor laminar structure, even at the youngest ages studied. At later ages and advanced disease stages, the ONL was thin and reduced in extent. Inner retinal thickness, in contrast, was normal or hyperthick. Inner retinal thickening was detectable at all ages studied and was strongly associated with ONL loss. CONCLUSIONS: Inner retinal laminar abnormalities in RPGR-XLRP are likely to reflect a neuronal-glial retinal remodeling response to photoreceptor loss and are detectable relatively early in the disease course. These results should be factored into emerging therapeutic strategies for this form of RP. 相似文献