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31.
OBJECT: The authors tested the hypothesis that intracranial bone marrow (BM) transplantation after traumatic brain injury (TBI) in rats provides therapeutic benefit. METHODS: Sixty-six adult Wistar rats, weighing 275 to 350 g each, were used for the experiment. Bone marrow prelabeled with bromodeoxyuridine (BrdU) was harvested from tibias and femurs of healthy adult rats. Other animals were subjected to controlled cortical impact, and BM was injected adjacent to the contusion 24 hours after the impact. The animals were killed at 4, 7, 14, or 28 days after transplantation. Motor function was evaluated both before and after the injury by using the rotarod test. After the animals had been killed, brain sections were examined using hemotoxylin and eosin and immunohistochemical staining methods. Histological examination revealed that, after transplantation, BM cells survived, proliferated, and migrated toward the injury site. Some of the BrdU-labeled BM cells were reactive, with astrocytic (glial fibrillary acid protein) and neuronal (NeuN and microtubule-associated protein) markers. Transplanted BM expressed proteins phenotypical of intrinsic brain cells, that is, neurons and astrocytes. A statistically significant improvement in motor function in rats that underwent BM transplantation, compared with control rats, was detected at 14 and 28 days posttransplantation. CONCLUSIONS: On the basis of their findings, the authors assert that BM transplantation improves neurological outcome and that BM cells survive and express nerve cell proteins after TBI.  相似文献   
32.
A young girl presented with history of prolonged fever, vomiting and headache. CT scan of brain revealed a space occupying lesion in posterior cranial fossa with moderate hydrocephalus. Surgery was performed and histopathology report confirmed the lesion as tuberculous. Patient showed smooth postoperative recovery and complete remission of complaints on antituberculous treatment for one year and regular follow-up.  相似文献   
33.
The need for orthodontic treatment is increasing all the time. As the treatment is time consuming ranging from a year to several years, any method of reducing the period of treatment and increasing the quality of the tissue will be beneficial to patients. The use of non-invasive techniques such as low level laser therapy and low intensity pulsed ultasound in accelerating orthodontic tooth movement are promising. Thus, this overview study will help to generate more understanding about the background information and the possible applications of them in daily orthodontics, depending on previous literature searching for reviews and original research articles.  相似文献   
34.

Background/Purpose

Early clinical predictors for the use of ECMO in patients with congenital diaphragmatic hernia (CDH) are lacking. We sought to evaluate the first 24-h SNAP-II score and highest PaCO2 as predictors of ECMO support and in-hospital mortality in neonates with CDH.

Methods

Retrospective review of 47 consecutive neonates with CDH admitted to our institution from January 2007 to December 2010 was performed. Covariates of ECMO use including SNAP-II score and highest PaCO2 within the first 24 h of NICU admission were evaluated.

Results

Of the 47 infants in this study, 24 patients were supported with ECMO. The ECMO group had a higher incidence of pulmonary hypertension, higher PaCO2, and higher 24-h SNAP-II scores. Only the SNAP-II score and not highest PaCO2 predicted mortality following multivariate adjustment.

Conclusions

The first 24-h SNAP-II score and highest PaCO2 may provide some prognostic value in identifying neonates who undergo ECMO support; however neither measure was independently associated with the use of therapy. Only the SNAP-II score was associated with in-hospital mortality following multivariate adjustment. Additional study is needed to validate these results in a larger data set.  相似文献   
35.
We have developed a simple rat model of angulated tibial fracture which elicits substantial differences in bone formation and resorption within the same bone. In 35 rats the right mid-tibia was manually fractured and fixed with an intramedullary 17-gauge cannula needle. Twenty tibias were fixed in anterior angulation (27 ± 5°) and 15 in posterior angulation (31 ± 5°). Serial X-rays were taken over a 12-week period. All fractures healed completely within five weeks. In both groups, bone thickness was already significantly greater on the concave side than on the convex side at week 3 and remained so until the end of the experiment. The thickness on the convex side decreased dramatically within 3 to 5 weeks and gradually thereafter. For morphological analysis of bone mineralization, 3 rats from each group were given calcein and alizarin red injected at different time points up to 14 weeks. Maximum new bone formation was noted within the first 3 weeks. Over the ensuing weeks, new bone formation remained intense on the concave side, but it was virtually absent on the convex side. These results show that angulated fracture deformity reproducibly exhibits differential bone turnover, which can be exploited in research on local regulatory factors. To exemplify the utility of the model, an immunohistochemical study on two local markers was done. Callus tissue of five rats in the anterior angulation group at week 3 post-fracture was stained for the cytokine IL-1, a stimulator of bone resorption, and the neuropeptide CGRP, an inhibitor of resorption, showing clear differences in positive staining between the concave and convex sides. Our in-vivo model offers a means of analyzing morphologically and quantitatively the differential expression and action of factors involved in local bone turnover.  相似文献   
36.
OBJECT: Atorvastatin, a beta-hydroxy-beta-methylglutaryl coenzyme A reductase inhibitor, has pleiotropic effects, such as promoting angiogenesis, increasing fibrinolysis, and reducing inflammatory responses, and has shown promise in enhancing recovery in animals with traumatic brain injury (TBI) and stroke. The authors tested the effect of atorvastatin on vascular changes after TBI. METHODS: Male Wistar rats subjected to controlled cortical impact injury were perfused at different time points with fluorescein isothiocyanate (FITC)--conjugated dextran 1 minute before being killed. Spatial memory function had been measured using a Morris Water Maze test at various points before and after TBI. The temporal profile of intravascular thrombosis and vascular changes was measured on brain tissue sections by using a microcomputer imaging device and a laser confocal microscopy. The study revealed the following results. 1) Vessels in the lesion boundary zone and hippocampal CA3 region showed a variety of damage, morphological alterations, reduced perfusion, and intraluminal microthrombin formation. 2) Atorvastatin enhanced FITC-dextran perfusion of vessels and reduced intravascular coagulation. 3) Atorvastatin promoted the restoration of spatial memory function. CONCLUSIONS. These results indicated that atorvastatin warrants investigation as a potential therapeutic drug for TBI.  相似文献   
37.

Introduction

Thrombosis is frequently observed in Galen malformation, but propagation of thrombosis resulting in the disappearance of the aneurysmal malformation is a very rare clinical condition.

Case report

A rare case of spontaneous regression and disappearance of the vein of Galen aneurysmal malformation (VoGAM) in a pediatric patient with repeated generalized seizure, increased head circumference, and congestive heart failure is recorded. The course of regression from infancy to 8 years of age has been depicted. Radiological studies initially demonstrated VoGAM complicated by an intra-cerebral hemorrhage and hydrocephalus, which later underwent spontaneous regression. Long-term clinical and radiological follow-up is presented.

Discussion

Different conditions including hemodynamic alteration, compression of adjacent hematoma, and narrowing of related vascular structures have been described to cause thrombosis of VoGAM. The relevant literature to address possible mechanism is reviewed.
  相似文献   
38.
A case of hydronephrosis with a rare underlying cause in a 35 years old male is described. He reported with pain in the left lumbar region with a past history of left ureterolithotomy. The ultrasound and IVU studies were suggestive of left hydronephroureter. CT Scan showed left hydronephroureter with narrowing at the lower end of left ureter. Ureterorenoscopy (URS) confirmed polypoidal lesions in the left lower ureter, completely obliterating the lumen and involving the whole circumferential wall of the lower ureter. The biopsy of the lesion revealed an inflammatory polyp. Accordingly open surgical intervention was planned. Excision of the lower third of left ureter with ureteric reimplantation was done with a Boari flap. The histopathology report of the lower third of ureter confirmed inverted papilloma of ureter. The patient made a smooth postoperative recovery.  相似文献   
39.
BACKGROUND AND METHOD: Posttransplantation acute pancreatitis (PTAP) is a rare but serious complication after pediatric liver transplantation (LTx). We performed a retrospective review in a large cohort of pediatric liver transplant recipients at a single institution to define the impact of this problem in children. RESULTS: Between January 1986 and December 1999, 634 pediatric LTx were performed. Twenty-six patients developed serious acute pancreatitis. The mean age at transplantation was 7.7 years (9 months to 19 years), and the indications for transplantation were biliary atresia in seven, fulminant hepatic failure in six, chronic rejection in seven, and other etiologies in six patients. PTAP was more likely to occur early after LTx (61% within the first week), was associated with the presence of an infrarenal aortic graft in 14 (54%) of 26 patients, was more likely to occur after retransplantation (11/26 patients), and was associated with blood loss and prolonged surgery in four cases. Acute renal failure occurred in 15 (58%) of 26 patients. Mortality was 42% (11/26); causes of death were sepsis or multiple organ failure in nine and hemorrhage in two patients. Management of PTAP included antibiotics, sphincterotomy, debridement with drainage, hepatic arterial revascularization, and arterial ligation. Of the 14 patients with complicated pancreatitis, 5 were treated conservatively and died. Nine patients had extensive operative interventions and four survived (45%). CONCLUSIONS: Several risk factors such as retransplantation, extensive dissection at the time of LTx, and use of infrarenal arterial graft contribute to development of PTAP in children. Early exploration and debridement in patients with complicated pancreatitis may result in a better outcome. Retransplantation in the presence of clinical pancreatitis has a high failure rate.  相似文献   
40.
Basiri A  Shadpour P  Moradi MR  Ahmadinia H  Madaen K 《The Journal of urology》2002,168(5):2166-9; discussion 2169
PURPOSE: The outcome of symphysiotomy for accessing pelvic fracture related, obliterative urethral strictures is described. MATERIALS AND METHOD: In 7 boys and 3 girls 4 to 13 years old (mean age 6) surgical correction of a pelvic fracture related, obliterative urethral stricture was achieved through symphysiotomy. The stricture involved a prostatomembranous location in boys and complete vesicourethral distraction in girls. Patients were followed an average of 2.5 years (range 6 months to 4 years) by physical examination, urethrography and endoscopy. RESULTS: The stricture was successfully corrected in all patients and all void with a normal flow. All boys are continent but 2 of the 3 girls had early incontinence, which resolved with time in 1. In 2 of the 10 cases a previous attempt at perineal repair had already failed. No patient required urethrotomy or dilation and none had significant hemorrhage, fistulization, bladder hernia, chronic pain or secondary gait disturbance. CONCLUSIONS: Symphysiotomy is hereby revisited as a simple and effective approach for repairing traumatic posterior urethral injuries in the pediatric population. It can be performed instead of transpubic urethroplasty to manage long or otherwise complicated strictures.  相似文献   
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