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991.

Purpose

To assess a virtual pointer in supporting surgical trainees’ development of professional vision in laparoscopic surgery.

Methods

We developed a virtual pointing and telestration system utilizing the Microsoft Kinect movement sensor as an overlay for any imagine system. Training with the application was compared to a standard condition, i.e., verbal instruction with un-mediated gestures, in a laparoscopic training environment. Seven trainees performed four simulated laparoscopic tasks guided by an experienced surgeon as the trainer. Trainee performance was subjectively assessed by the trainee and trainer, and objectively measured by number of errors, time to task completion, and economy of movement.

Results

No significant differences in errors and time to task completion were obtained between virtual pointer and standard conditions. Economy of movement in the non-dominant hand was significantly improved when using virtual pointer (\(p = 0.012\)). The trainers perceived a significant improvement in trainee performance in virtual pointer condition (\(p < 0.001\)), while the trainees perceived no difference. The trainers’ perception of economy of movement was similar between the two conditions in the initial three runs and became significantly improved in virtual pointer condition in the fourth run (\(p = 0.017\)).

Conclusions

Results show that the virtual pointer system improves the trainer’s perception of trainee’s performance and this is reflected in the objective performance measures in the third and fourth training runs. The benefit of a virtual pointing and telestration system may be perceived by the trainers early on in training, but this is not evident in objective trainee performance until further mastery has been attained. In addition, the performance improvement of economy of motion specifically shows that the virtual pointer improves the adoption of professional vision— improved ability to see and use laparoscopic video results in more direct instrument movement.
  相似文献   
992.
993.
Injectable bone fillers represent an attractive strategy for the treatment of bone defects. These injectable materials should be biocompatible, capable of supporting cell growth and possibly able to exert antibacterial effects. In this work, nanocomposite microbeads based on alginate, chitlac, hydroxyapatite and silver nanoparticles were prepared and characterized. The dried microbeads displayed a rapid swelling in contact with simulated body fluid and maintained their integrity for more than 30 days. The evaluation of silver leakage from the microbeads showed that the antibacterial metal is slowly released in saline solution, with less than 6% of silver released after 1 week. Antibacterial tests proved that the microbeads displayed bactericidal effects toward Staphylococcus aureus, Pseudomonas aeruginosa and Staphylococcus epidermidis, and were also able to damage pre‐formed bacterial biofilms. On the other hand, the microbeads did not exert any cytotoxic effect towards osteoblast‐like cells. After characterization of the microbeads bioactivity, a possible means to embed them in a fluid medium was explored in order to obtain an injectable paste. Upon suspension of the particles in alginate solution or alginate/hyaluronic acid mixtures, a homogenous and time‐stable paste was obtained. Mechanical tests enabled to quantify the extrusion forces from surgical syringes, pointing out the proper injectability of the material. This novel antibacterial bone filler appears as a promising material for the treatment of bone defects, in particular when possible infections could compromise the bone‐healing process. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
994.
Schwann cells are promising candidates for transplantation strategies in the central nervous system by promoting axonal regeneration. The dog represents a translational model for human spinal cord injury (SCI) for studies with new repair strategies after intervertebral disk herniation (IVDH). To overcome the necessity for an additional surgical procedure, for the first time a protocol for the isolation and purification of canine Schwann cells from spinal nerve biopsies during standard hemilaminectomy in IVDH‐affected paraplegic dogs for potential transplantation has been developed. Purity was assessed by flow cytometry. The results were compared with biopsies from dogs without SCI. Within 26 ± 4 days, 90.2 ± 8.8% p75 neurotrophin receptor (p75NTR)‐positive cells were achieved in IVDH dogs. The total cell count in acute/subacute and chronic IVDH (acute/subacute: 6.82 ± 6.36 × 106; chronic: 2.29 ± 2.00 × 106) differed significantly (p = 0.0120) at the potential time point of transplantation. No differences in culture period and purity were detected between dogs with and without IVDH. Despite the small sample size and the altered environment, the isolation of Schwann cells was successful. Negative influences on isolation and purification due to potential pathological changes at the biopsy site of IVDH‐diseased dogs were ruled out by comparison of Schwann cell pellets from diseased and control dogs. Finally, the functionality of Schwann cells from dogs with IVDH was outlined in co‐culture experiments with canine dorsal root ganglion neurons. In conclusion, nerve root biopsies provide a sufficient number of highly purified and functional Schwann cells within a useful time period for novel therapeutic strategies in dogs with SCI.  相似文献   
995.
Progressive supranuclear palsy (PSP) is a progressive neurodegenerative disorder caused by the deposition of abnormal proteins in neurons of the basal ganglia that limit motor ability, resulting in disability and reduced quality of life. So far, no pharmacologic therapy has been developed, and the treatment remains symptomatic. The aim of the present study is to perform a systematic investigation of the literature, and to determine the types and effects of rehabilitative interventions used for PSP. A search of all studies was conducted in MEDLINE/PubMed, the Cochrane Central Register of Controlled Trials, CINAHL, and EMBASE. Twelve studies were identified, including 6 case reports, 3 case series, one case-control study, one quasi?randomized trial (i.e. not truly random) with crossover design, and one randomized controlled trial, with 88 patients investigated overall. Rehabilitative interventions varied in type, number, frequency, and duration of sessions. The most commonly used clinical measures were the Progressive Supranuclear Palsy Rating Scale (PSPRS) and Unified Parkinson's Disease Rating Scale (UPDRS). Physical exercises were the main rehabilitative strategy but were associated with other interventions and rehabilitative devices, in particular treadmill and robot-assisted gait training. All studies showed an improvement in balance and gait impairment with a reduction of falls after rehabilitation treatment. Because of poor methodological quality and the variety of rehabilitative approaches including different and variable strategies, there was insufficient evidence of the effectiveness of any specific rehabilitation intervention in PSP. Despite this finding, rehabilitation might improve balance and gait, thereby reducing falls in PSP patients.

Level of Evidence

IV  相似文献   
996.

Background

Mental health problems are common after pediatric traumatic brain injury (TBI). Many patients in need of mental health services do not receive them, but studies have not consistently used prospective and objective methods or followed samples for more than 1 year.

Objective

To examine adolescents’ use of mental health services after TBI.

Design

Secondary analysis from multicenter prospective randomized controlled trial.

Setting

Five level 1 U.S. trauma centers.

Participants

Adolescents aged 12-17 years with moderate-to-severe TBI were recruited for a randomized clinical trial (n = 132 at baseline, 124 at 6 months, 113 at 12 months, and 101 at 18 months).

Methods

Participants were randomly assigned to counselor-assisted problem-solving or Internet resource comparison. Follow-up assessments were completed at 6, 12, and 18 months after baseline. Generalized estimating equations with a logit link were used to examine use of mental health services. Treatment group and participant impairment were examined as predictors of use.

Main Outcome Measurements

Mental health care use was measured with the Service Assessment for Children and Adolescents; daily functioning and clinical outcome with the Child and Adolescent Functional Assessment Scale; behavioral and emotional functioning with the Child Behavior Checklist; and executive dysfunction with the Behavior Rating Inventory of Executive Function.

Results

Use of mental health services ranged from 22% to 31% in the 2 years post-TBI. Participants with impairments were about 3 times more likely than those without impairments to receive services (odds ratio 4.61; 95% confidence interval 2.61-8.14; P < .001). However, 50%-68% of patients identified as impaired had unmet mental health care needs.

Conclusions

Less than one half of adolescents with behavioral health needs after TBI received mental health services. Future studies are needed to examine barriers associated with seeking services after TBI and psychoeducation as preventive care for this population.

Level of Evidence

II  相似文献   
997.
998.
999.
Kinesio Taping® elastic tape is increasingly used in physiotherapy treatment. However, there is a lack of scientific research regarding the late effects of its use. This study quantified the late effects of applying the Kinesio Taping® elastic tape by measuring changes in handgrip muscle strength after 24, 48 and 72 h of application. The Kinesio Taping® elastic tape was applied on the dominant and non-dominant limbs of 36 volunteers randomly assigned to three groups: muscle facilitation, muscle inhibition and control group. The statistical test showed there was a statistically significant difference among all groups of dominant limb and non-dominant limb. However, the analysis on intragroup relationship to periods of application (Initial, 24, 48 and 72 h) and the interaction among repeated measures showed there was no statistically significant difference. This result may contribute to the investigation of the late effects of the Kinesio Taping® elastic tape on the physical rehabilitation.  相似文献   
1000.
Introduction: Non-alcoholic fatty liver disease (NAFLD) has the potential to progress to hepatocellular carcinoma (HCC). However, limited therapies are currently available for the treatment of advanced HCC, and one must strive to search for novel strategies.

Areas covered: We provide insight on current knowledge related to gut microbiota and NAFLD, summarize the sequence linking obesity to HCC and highlight gut dysbiosis in obesity and its consequences on the liver. We detail the impact of the gut microbiota on immune checkpoint inhibitors, and speculate on the role of fecal microbiota transplantation (FMT) in NAFLD and in improving anti-neoplastic immune response.

Expert Opinion: Manipulation of the gut microbiota seems promising in the secondary prevention of NAFLD/NASH and/or in potentiating anti-cancer immune response, notably by a global ‘resetting’ using FMT. However, the composition of a ‘harmful’ gut microbiome in HCC still needs to be characterized, and the impact of FMT on HCC growth needs to be assessed.  相似文献   

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