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61.

Introduction

The purpose of this study was to evaluate the impact of computed tomography scanning on the inter- and intra-observer reliability of the OTA/AO, the Schatzker, and the Hohl classifications in the assessment of tibial plateau fractures.

Methods

Four independent observers classified 45 consecutive fractures of the tibial plateau according to the criteria of the OTA/AO system, the Schatzker classification, and the Hohl classification. Two sessions of readings were compared; first, the use of plain anterior-posterior and lateral X-rays alone was evaluated, then 4 weeks later the combination of plain X-rays and two-dimensional computed tomography scans were evaluated. The readings were repeated 8 weeks later to evaluate intra-observer reliability.

Results

The three classification systems showed “moderate” inter-observer reliability and “good” and “moderate” intra-observer reliability when classified solely on the basis of plain radiographs. After the addition of computed tomography scans inter-observer reliability significantly improved to “good” in all classifications. Likewise, intra-observer reliability improved to “good” in all classifications after the addition of CT-scans. Statistical analysis showed no significant difference regarding inter- and intra-observer agreement between the three classifications.

Conclusions

Computed tomography scanning improved the inter- and intra-observer reliability of the OTA/AO, the Schatzker, and the Hohl classification. Overall, all three classification systems showed “good” inter- and intra-observer reproducibility when classified with CT-scans.  相似文献   
62.
Multiple sclerosis (MS) is an autoimmune disorder directed against self antigens of the central nervous system. CD4+CD25+FoxP3+ regulatory T cell (Treg) mediated suppression is an essential mechanism of self-tolerance. We studied whether changes in the suppressive function of a mixture of CD25high and CD25intemediate expressing Treg cells in myelin basic protein (MBP)-induced proliferation occurred in untreated MS patients. Suppression of MBP-induced proliferation was observed in 13 out of 29 (45%) MS patients; this was significantly (p < 0.05) less compared with 17 out of 19 (89%) healthy individuals. Relative Treg counts was significantly increased in MS patients (mean ± S.D.; 20 ± 8%) compared with healthy individuals (15 ± 5%). These findings suggest that impaired Treg function may be involved in pathogenesis of MS.  相似文献   
63.
Recent studies have shown that in the aetiology of attention-deficit hyperactivity disorder (ADHD) genetic factors may be of importance. Biochemical and pharmacological studies reveal a connection between abnormalities of dopaminergic, adrenergic and serotonergic system and ADHD. Therefore genes for enzymes synthesizing or degrading proper neurotransmitters, genes for adequate transporters and receptors and genes for other substances, which altered the level of neurotransmitters, are studied. Many authors describe the connection between ADHD development and the synaptosomal-associated protein 25 (SNAP-25) gene. This protein plays a role in catecholamine secretion. Its higher expression is specific for neurones. SNAP-25 gene mutation may change this protein level, function of synapse and neurotransmitters storage. Acetylcholine receptor alpha4 subunit gene stimulation increases the dopamine level. Therefore this receptor gene may be important in the aetiology of ADHD studies. Other possible factors in ADHD background are substance influence on brain maturation, including N-methyl-D aspartate glutamate receptor 2A gene polymorphism (GRIN2A) and brain derived neurotrophic factor (BDNF) gene. One of the greatest challenges in studying the genetic basis of psychiatric disorders is to find appropriate ways to define the relevant endophenotype. ADHD often coexists with other psychiatric disorders, including specific developmental disorders, conduct disorders, obsessive-compulsive disorder and early onset of bipolar disorder.  相似文献   
64.
BACKGROUND: CO-releasing molecule-3 (CORM-3) is a transitional metal carbonyl that liberates carbon monoxide under appropriate conditions. Carbon monoxide exerts effects on intracellular apoptotic and inflammatory pathways, which suggest a role in reducing the effects of renal ischemia/reperfusion (I/R) injury. This study investigated the effects of CORM-3 administered at the time of reperfusion in a model of controlled nonheartbeating donor kidneys. METHODS: Porcine kidneys (n=4) were subjected to 10 min warm ischemia and 18 hr cold storage (CS) and then treated as follows: CORM-3 (50, 100, 200, and 400 microM doses), iCORM-3 (inactive carbon monoxide-releasing molecule, 50 microM), and control (no further intervention). Renal hemodynamics and function were then measured during 3-hr reperfusion with autologous blood using an isolated organ-perfusion system. RESULTS: CORM-3 at a concentration of 50 microM improved renal blood flow (RBF) compared with the iCORM and control groups (area under the curve 774+/-19 vs. 448+/-88 vs. 325+/-70, respectively, P=0.002). CO-releasing molecule-3 at a concentration of 50 microM also improved renal function during reperfusion with a greater area under the curve for creatinine clearance (CORM-3: 14+/-6 vs. iCORM: 3.3+/-0.1 vs. control: 2.2+/-2 mL/min, P=0.006) and higher urine output (CORM-3: 793+/-212 vs. iCORM: 368+/-72 vs. control: 302+/-211 mL, P=0.01). CO-releasing molecule-3 at a concentration of 100 microM exerted similar effects. Treatment with CORM-3 at higher doses (200 and 400 microM) led to poor renal hemodynamics and function after reperfusion. CONCLUSION: Low-dose CORM-3 significantly ameliorates the effects of ischemia/reperfusion in a porcine model of controlled nonheartbeating donor kidney transplantation.  相似文献   
65.
Immune responses have been shown to be involved in the pathogenesis of clinical complications of cortical bone allografts. In an attempt to reduce the immunogenicity of these allografts, we evaluated cortical bone allografts modified by laser perforation and partial demineralization transplanted orthotopically into sheep tibiae. The recipient animals were divided into three groups, of eight animals each, according to the type of cortical allograft that was transplanted: group 1, no treatment (control); group 2, demineralization only; and group 3, laser perforation and partial demineralization. All animals were tissue-typed by biochemical definition of MHC class I molecules, using unidimensional isoelectric focusing and Western blotting. Mismatches of donors and recipients were assessed by testing samples of each donor and recipient pair in parallel and by comparing their individual bands. Donor-specific alloantibodies were detected by a similar technique, using an enzyme-linked immunosorbent assay (ELISA) format. Negative controls were included in all tests. All grafts were poorly immunogenic, whether they were untreated, processed by partial demineralization, or processed by both laser perforation and partial demineralization. Only two recipient animals showed a transient, antibody-mediated donor-specific immune response. One of these animals had received a control allograft, whereas the other animal had received a laser-perforated and partially demineralized bone allograft. All of the grafts in this study, including control grafts, were stripped of soft tissues and their bone marrow was removed; cellular sources of alloantibody stimulation may have been eliminated by these processes. The results of this study suggest that immune responses to bone allografts may be reduced by removing the bone marrow and adjacent soft tissues. The processing of cortical bone allografts by laser perforation and partial demineralization appeared to have little effect on immune responses.  相似文献   
66.
INTRODUCTION: Choosing surgery as a career is declining among U.S. medical students. The 8-wk third year surgery clerkship at our institution can be an intense learning experience, and we hypothesized that during this clerkship medical student quality-of-life would drop significantly from baseline, and that this drop would be greater among certain subgroups, such as women students not interested in pursuing a surgical career, and those who place a high value on a controllable lifestyle. METHODS: At clerkship orientation (baseline), students were asked to complete a survey that measured quality-of-life on an 84-point scale, and depression on a 40-point scale. The quality-of-life scale was composed of select questions from the Medical Outcomes Study, and the Harvard Department of Psychiatry/NDSD brief screening instrument was used to measure depression. Students were also asked the typical number of hours they slept per night. Demographics, attitude toward a controllable lifestyle, and top three specialties of interest were also gathered at baseline. On week 6 of the clerkship, students were surveyed on the same quality-of -life and depression scales, and asked average hours of sleep per night for the previous week. RESULTS: From June 2005 through December 2006, 143 of 177 (81%) students agreed to participate, and after exclusions for missing data, 137 students were included in the analysis. Sixty-nine students were women (51%), and the average age was 25.8 (sd 2.6). Mean quality-of-life at baseline was 57.0 (sd 11.3) and at week 6 was 50.4 (sd 10.1) representing a statistically significant average decline of 6.6 points (P < 0.0001). Mean depression at baseline was 14.4 (sd 3.8) and at week 6 was 15.1 (sd 3.6), representing a small but significant average decline of 0.7 points (P = 0.0155). Mean sleep at baseline was 6.3 h/night (sd 0.9) and at week 6 was 5.7 h/night (sd 1.2), representing a statistically significant average decline of 0.6 h/night (P < 0.0001). Declines were similar on all outcomes between men versus women, those who ranked surgery in their top three career choices versus those who did not, and those who ranked controllable lifestyle as "very important" versus all other categories. CONCLUSION: Quality-of-life and sleep declines and depression increases significantly in third-year medical students from orientation to week 6 of their surgery clerkship at our institution. We look forward to studying quality-of-life on other clerkships for comparison, assessing whether the magnitude of this decline in quality-of-life predicts students avoiding a future career in surgery, and testing interventions to prevent this decline in quality-of-life during the clerkship.  相似文献   
67.
BACKGROUND: We have demonstrated that pyridoxal 5'-phosphate (PLP), an active form of vitamin B6, inhibits formation of advanced glycation end-products (AGEs) by trapping 3-deoxyglucosone. The present study aimed to clarify if PLP could exert beneficial effects on nephropathy in diabetic rats. METHODS: Streptozotocin (STZ)-induced diabetic rats were treated by oral administration of PLP or pyridoxamine (PM), another active form of vitamin B6, at a dose of 600 mg/kg/day for 16 weeks. AGEs [imidazolone, N(epsilon)-(carboxymethyl)lysine (CML) and N(2)-carboxyethyl-2'-deoxyguanosine (CEdG)], transforming growth factor-beta1 (TGF-beta1), type 1 collagen and fibronectin were detected in the kidneys using immunohistochemistry. Gene expression of TGF-beta1 and receptor for AGEs (RAGEs) in the kidneys was determined using real-time quantitative polymerase chain reaction. RESULTS: Administration of PLP significantly inhibited albuminuria, glomerular hypertrophy, mesangial expansion, and interstitial fibrosis as compared with diabetic rats. PLP markedly inhibited accumulation of AGEs such as imidazolone, CML and CEdG, a DNA-linked AGE, in glomeruli. PLP significantly inhibited expression of TGF-beta1, type 1 collagen, fibronectin and RAGE in the kidneys. PLP was superior to PM in inhibiting accumulation of AGEs, expression of TGF-beta1, type 1 collagen, and fibronectin, and the development of diabetic nephropathy. CONCLUSIONS: PLP prevented progression of nephropathy in STZ-induced diabetic rats by inhibiting formation of AGEs. PLP is considered a promising active form of vitamin B6 for the treatment of AGE-linked disorders such as diabetic nephropathy.  相似文献   
68.

Purpose

Latissimus dorsi and teres major transfers to the lateral side of the humerus with lengthening of the pectoralis major and subscapularis muscles for residual shoulder deformity were compared in children and skeletally mature patients.

Methods

Fifteen patients (nine children, six skeletally mature patients aged three to 30 years, follow-up one to 22 years) were treated for internal shoulder contracture after birth plexus lesions: C5–C6 (seven patients); C5–7 (five patients); C5-C8-T1 (three patients, respectively). Range of movement, Mallet shoulder function score and radiographs were assessed.

Results

Pre-operatively, shoulder function restrictions were comparable in all patients. Postoperatively, external rotation, abduction and Mallet function score improved significantly (p < 0.05) in all patients except one. There were no differences in improvement between children and skeletally mature patients (p = 0.24–1.0).

Conclusions

This technique improves external rotation and abduction of the shoulder for daily living activities in children and young, skeletally mature, patients.  相似文献   
69.

Background

Postoperative peritoneal carcinomatosis together with adhesion formation are considered as two major clinical complications after resection of malignant abdominal tumors, jeopardizing the beneficial effect of the curative surgery. Biobarrier is a novel anti-adhesive barrier fulfilling the criteria for a good adhesion preventive agent, possessing biochemical properties that may enable it to function as a dual efficient device, reducing both adhesion and tumor development. This study aims to evaluate the effect of novel anti-adhesive device Biobarrier on intra-abdominal tumor progression.

Materials and methods

Cells from cancer cell line BN7005H1D2 were treated with Biobarrier to determine the effect of Biobarrier on cell attachment and viability in vitro. For the in vivo experiments, bilateral peritoneal trauma was inflicted in a reproducible syngeneic rat model. To mimic the clinical situation, the animals received an intraperitoneal injection of BN7005H1D2 cancer cells at the end of surgery, resembling perioperative tumor spill after intraperitoneal instillation of Biobarrier. Animals without given anti-adhesive treatment were used as control.

Results

Biobarrier applied in vitro hindered cells from attachment to the wells. In vivo treatment with Biobarrier significantly reduced tumor growth at both sites of surgical trauma (P = 0.001 and 0.015) and other non-traumatized intraperitoneal sites (P = 0.021).

Conclusions

Biobarrier maybe effective in reducing intra-abdominal tumor cell implantation with subsequent tumor development in conjunction with peritoneal trauma in a syngeneic rat model.  相似文献   
70.
Background contextAlthough the incidence of pyogenic spinal infections is increasing, the ideal treatment of spondylodiscitis is still a controversially discussed issue. Furthermore, the proportion of multiresistant bacteria in spondylodiscitis is increasing, and treatment recommendations or reported results are missing for this especially difficult subset of patients.PurposeThe aim of this study is to evaluate the surgical outcome and the postoperative antibacterial treatment regime.Study designRetrospective case series.Patient samplePatients treated for a spondylodiscitis from multiresistant bacteria at our department between 2006 and 2011.MethodsData were gathered through review of patients' case notes, relevant imaging, and electronic records. Magnetic resonance imaging of the whole spine including gadolinium (Gd)-enhanced T1 sequences and computed tomography scans of the affected regions were obtained in all cases.Outcome measuresC-reactive protein (CRP) and complete blood cell count were analyzed in all cases using routine laboratory techniques. Neurologic deficits were classified according to the American Spinal Injury Association (ASIA) impairment scale.ResultsTwenty-five patients were identified (15 gram-positive and 10 gram-negative drug-multiresistant bacteria). The mean age at presentation was 66 years, and 14 patients were male (56%). All patients presented with pain, and a neurologic deficit was present in 11 (44%) cases. An epidural abscess was found in 11 (44%) cases. At admission, CRP was elevated in all cases with a mean of 13±9.2 mg/dL. The main source of infection was previous spine surgery (36%). All patients in this series underwent surgical debridement of the infection and instrumentation of the spine. Postoperative intravenous antibiotics were administered for 19±8.6 days followed by 3±0.3 months of oral antibiotic therapy. Eradication of the infection was achieved ultimately in all surviving patients. Out of 11 patients with neurologic deficits, 4 had a full recovery, 4 improved incompletely, and 3 remained unchanged after surgery.ConclusionsStaged surgical immobilization and instrumentation and optimal debridement at the interdiscal space and spinal canal is a reliable approach to achieve complete healing of spinal infection with multiresistant bacteria. A period of intravenous antibiotic therapy of 2 to 3 weeks followed by a 3-month oral antibiotic therapy seems appropriate for most cases.  相似文献   
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