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31.

Purpose

Sciatic nerve block (SNB) is commonly performed in combination with femoral nerve block (FNB) for postoperative analgesia following total knee arthroplasty (TKA). Despite the fact that 10–20 % of TKA patients require SNB for postoperative posterior knee pain, there are no existing studies that suggest a model to predict the need for SNB. The aim of our study was to develop a prediction tool to measure the likelihood of patients undergoing TKA surgery requiring a postoperative SNB.

Methods

With institutional review board approval, we obtained data from the electronic medical record of patients who underwent TKA at the Cleveland Clinic. A multivariable logistic regression was used to estimate the probability of requiring a postoperative SNB. Clinicians selected potential predictors to create a model, and the potential nonlinear association between continuous predictors and SNB was assessed using the restricted cubic spline model.

Results

In total 6279 TKA cases involving 2329 patients with complete datasets were used for building the prediction model, including 276 (12 %) patients who received a postoperative SNB and 2053 (88 %) patients who did not. The estimated C statistic of the prediction model was 0.64. The nomogram is used by first locating the patient position on each predictor variable scale, which has corresponding prognostic points. The cut-off of 11.6 % jointly maximizes the sensitivity and specificity.

Conclusion

This is the first study to be published on SNB prediction after TKA. Our nomogram may prove to be a useful tool for guiding physicians in terms of their decisions regarding SNB.
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33.
The structure and function LT-IIa, a type II heat-labile enterotoxin of Escherichia coli, are closely related to the structures and functions of cholera toxin and LT-I, the type I heat-labile enterotoxins of Vibrio cholerae and enterotoxigenic Escherichia coli, respectively. While LT-IIa is a potent systemic and mucosal adjuvant, recent studies demonstrated that mutant LT-IIa(T34I), which exhibits no detectable binding activity as determined by an enzyme-linked immunosorbent assay, with gangliosides GD1b, GD1a, and GM1 is a very poor adjuvant. To evaluate whether other mutant LT-IIa enterotoxins that also exhibit diminished ganglioside-binding activities have greater adjuvant activities, BALB/c mice were immunized by the intranasal route with the surface adhesin protein AgI/II of Streptococcus mutans alone or in combination with LT-IIa, LT-IIa(T14S), LT-IIa(T14I), or LT-IIa(T14D). All three mutant enterotoxins potentiated strong mucosal immune responses that were equivalent to the response promulgated by wt LT-IIa. All three mutant enterotoxins augmented the systemic immune responses that correlated with their ganglioside-binding activities. Only LT-IIa and LT-IIa(T14S), however, enhanced expression of major histocompatibility complex class II and the costimulatory molecules CD40, CD80, and CD86 on splenic dendritic cells. LT-IIa(T14I) and LT-IIa(T14D) had extremely diminished toxicities in a mouse Y1 adrenal cell bioassay and reduced abilities to induce the accumulation of intracellular cyclic AMP in a macrophage cell line.  相似文献   
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35.
BackgroundThe most effective surgical approach to total hip replacement (THR) remains controversial. Most studies that have compared approaches have reported only short-term outcome data. It is therefore unclear in the literature if a particular surgical approach offers long-term advantages. The aim of this study was to determine the effect of the 3 main surgical approaches to THR on patient-reported outcomes 5 years after surgery.MethodsAll patients who underwent a THR for osteoarthritis or osteonecrosis between 2008 and 2012 by an anterior, posterior or lateral approach at The Ottawa Hospital in Ontario, Canada, were included in the study. All preoperative and postoperative scores for the Hip Disability and Osteoarthritis Outcome Score (HOOS) and Western Ontario and MacMaster Universities Osteoarthritis Index (WOMAC) questionnaires were recorded. Analysis of covariance was used to study the relationship between the amount of change in scores on the HOOS and WOMAC subscales (dependent variables) and the surgical approach. The confounding factors of age, sex, American Society of Anesthesiologists (ASA) class, Charnley classification and body mass index were included in the analysis.ResultsThere were 138 patients (37.6%) in the posterior approach group, 104 (28.3%) in the lateral approach group and 125 (34.1%) in the anterior approach group. There were no significant differences among the 3 groups in terms of Charnley classification, body mass index, sex, ASA class, surgical side and preoperative functional scores. We did not observe any significant differences in the amount of change in the scores for HOOS and WOMAC subscales among the 3 groups. There were also no differences in the final postoperative scores.ConclusionOur findings suggest that the choice of surgical approach in primary THR surgery without revision has no influence on functional outcomes and quality of life after 5 years. Further studies are needed to assess how patient age and sex may influence the functional outcome of individual surgical approaches.  相似文献   
36.

Objective

Aim is to compare the glycemic level among patients before, and after local anesthesia containing adrenaline 1:80,000 among patients who need dental extraction.

Materials and methods

60 patients were randomly selected including 30 healthy and 30 with a diabetes history for this study in Riyadh city. First the blood glucose level was measured before administering local anesthesia containing adrenaline after taking their history with glucocheck according to instructions, then blood Sugar level was recorded after administering local anesthesia containing adrenaline 1:80,000 concentrations. Blood sugar level was also checked 5 min after the tooth extraction procedure.

Results

There were no significant results found after the administration of local anesthesia containing adrenaline in both healthy and diabetic patients (p > 0.05). However, change of significance (p < 0.05) was noticed in diabetic patients who had not taken their hypoglycemic medication; there was a rise in their blood glucose level after extraction.

Conclusion

The study concluded no significant effect on the glycemic level of patients after the administration of local anesthesia containing adrenaline 1:80,000 in healthy and diabetic patients whether hypoglycemic medication was taken or not but a rise in blood sugar level was found among diabetic patients who did not take their hypoglycemic medications undergoing tooth extraction.  相似文献   
37.
Triterpenoid glycosides are molecules widely distributed in plants and have shown a wide range of biological activities against various diseases. This paper describes the qualitative and quantitative analysis of triterpenoid glycoside (saponins) using a two-stage mass spectrometry approach in five samples of Fagonia indica collected from various parts of the country. In the first stage, triterpenoid glycosides were identified using liquid chromatography high-resolution mass spectrometry using UHPLC-QTOF-MS system. In the second stage, compounds were quantified using a multiple reaction monitoring (MRM) approach using an UHPLC-QQQ-MS system. Fagonia indica has shown a wide range of biological activities and found to be rich in saponin or triterpenoid glycoside constituents. A total of thirteen triterpenoid saponins were identified based on high-resolution analysis, MS/MS and database comparison, while six of them were simultaneously quantified using the multiple reaction monitoring (MRM) approach. The results indicate that the samples share a similar UHPLC pattern, however, the amount of these saponins in samples varies greatly. Compound 4i.e. nayabin D was the major constituent (1.4–3.8 μg g−1) among the six analyzed compounds. The results demonstrated that the developed multi-compound determination in combination with a fingerprint analysis method is rapid, accurate, precise and sensitive and can be utilized for quality control and high-throughput quantification of various saponins in Fagonia indica may be extended to other plant species.

Development of a rapid, accurate, precise, and effective method for the analysis and quantification of saponins in crude extracts from Fagonia indica.  相似文献   
38.
Nanoparticles (NPs) are new inspiring clinical targets that have emerged from persistent efforts with unique properties and diverse applications. However, the main methods currently utilized in their production are not environmentally friendly. With the aim of promoting a green approach for the synthesis of NPs, this review describes eco-friendly methods for the preparation of biogenic NPs and the known mechanisms for their biosynthesis. Natural plant extracts contain many different secondary metabolites and biomolecules, including flavonoids, alkaloids, terpenoids, phenolic compounds and enzymes. Secondary metabolites can enable the reduction of metal ions to NPs in eco-friendly one-step synthetic processes. Moreover, the green synthesis of NPs using plant extracts often obviates the need for stabilizing and capping agents and yields biologically active shape- and size-dependent products. Herein, we review the formation of metallic NPs induced by natural extracts and list the plant extracts used in the synthesis of NPs. In addition, the use of bacterial and fungal extracts in the synthesis of NPs is highlighted, and the parameters that influence the rate of particle production, size, and morphology are discussed. Finally, the importance and uniqueness of NP-based products are illustrated, and their commercial applications in various fields are briefly featured.

Nanoparticles (NPs) are new inspiring clinical targets that have emerged from persistent efforts with unique properties and diverse applications.  相似文献   
39.

Background

The purpose of this study was to assess prospectively operative results and complications of treatment of cervical spinal canal stenosis (CCS) by anterior cervical discectomy and fusion (ACDF) using a newly introduced Alexandria Modular Cage-Plate Construct (AMCPC).

Methods

Fifteen patients (eight males, seven females) with symptomatic CCS were treated by ACDF, with a mean age of 51.2 years. Post-operative assessment depended upon clinical and radiological results.

Results

Total number of operated levels was 25 levels, with a mean 1.67 levels/patient. Mean operative time was 69.6 min/level and 116 min/patient. Average blood loss was 78 mL/level and 130 mL/patient. Mean hospital stay was 2.8 days. Post-operative dysphagia/dysphonia persisted in one patient for 1 year. One patient developed C5 radiculopathy with grade 2 deltoid weakness that recovered after 3 months. According to Odom’s criteria, results were excellent in 13 patients (86.67 %), good in 1 (6.67 %), and fair in 1 patient. In 13 patients (23 cage-plates, 92 %), the implant showed to be completely contained until the end of follow-up (24 months). One patient had a broken screw and one had screw backing-out, both did not necessitate revision. The achieved sagittal profile was maintained without sinking-in of any cage.

Conclusion

AMCPC can be used safely for a variety of disorders requiring instrumentation and fusion. It is advantageous to stand-alone cage and to rigid cage-plates when intraoperative flexibility is needed. It overcomes the disadvantages of stand-alone cage, sinking-in, cage dislodgement and post-operative rekyphosis. In addition, it obviates the need for wearing post-operative neck collar.  相似文献   
40.
Phenylethanoid glycosides (PhGs) are generally water-soluble phenolic compounds that occur in many medicinal plants. Until June 2020, more than 572 PhGs have been isolated and identified. PhGs possess antibacterial, anticancer, antidiabetic, anti-inflammatory, antiobesity, antioxidant, antiviral, and neuroprotective properties. Despite these promising benefits, PhGs have failed to fulfill their therapeutic applications due to their poor bioavailability. The attempts to understand their metabolic pathways to improve their bioavailability are investigated. In this review article, we will first summarize the number of PhGs compounds which is not accurate in the literature. The latest information on the biological activities, structure–activity relationships, mechanisms, and especially the clinical applications of PhGs will be reviewed. The bioavailability of PhGs will be summarized and factors leading to the low bioavailability will be analyzed. Recent advances in methods such as bioenhancers and nanotechnology to improve the bioavailability of PhGs are also summarized. The existing scientific gaps of PhGs in knowledge are also discussed, highlighting research directions in the future.  相似文献   
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