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1.

Objective

The aim of the study was to evaluate the loss of truncal rotation over 54 hours after removing Chêneau brace.

Methods

The studied groups consisted of 39 girls aged 10–18 years old, diagnosed with adolescent idiopathic scoliosis (AIS) and treated with Chêneau brace (CAST) and 20 AIS girls aged 10–18 years old, not treated with bracing. Posterior-anterior radiographs were obtained from the clinical assessment of all subjects and were subsequently used to determine Cobb angles. The measurements of the angle of trunk rotation (ATR) were taken with the Scoliometer® and back-contour device during Adams forward bending test by the two evaluators. The changes in ATRs during 54 hours of observation were performed after the brace had been taken off (0, 2, 24, 30, 48 and 54 hours after debracing). This was described using VATR variable, defined as the change in the absolute Scoliometer® readings in the time intervals against the time interval Δt between the measurements. During back-contour assessment the differential factor (kra) has been used for the digital analysis. The changes in kra over 54 hours of observation were expressed as Vkra factor, defined as the difference in the absolute value of the amplitude differential factor (kra) in the time intervals against the time interval Δt between the measurements.

Results

The highest changes were observed in the thoracic as well as in lumbar spine in patients with Cobb angle ≥30°, axial rotation of the apical vertebrae within 5–15°, Risser sign 0–2. The biggest change in the trunk rotation after Chêneau brace had been taken off was noted within the first two hours of observation.

Conclusion

The patients should be advised to take the brace off for a minimum of two hours before the scheduled x-ray, to allow full relaxation of the trunk in order to obtain reliable radiological images of the deformation.

Level of Evidence

Level III Therapeutic study.  相似文献   
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The aims of the study were to assess the clinical conformity between quantitative ultrasound (QUS) and densitometry with use of the standard World Health Organization T-score thresholds to determine optimal diagnostic cutoff values for QUS T-scores in different age groups. Three hundred sixty-five postmenopausal Caucasian women were enrolled into the study and divided into two age groups (<65 y and ≥65 y). Skeletal status was assessed using QUS measurements at the calcaneus and bone densitometry at the spine and proximal femur (Hologic Explorer, Bedford, MA, USA). QUS measurement results expressed as the stiffness index (SI) correlated significantly with both femoral neck bone mineral density (r = 0.51, p < 0.0001) and lumbar spine bone mineral density (r = 0.52, p < 0.0001). On the basis of receiver operating characteristic curve analyses, the thresholds for correspondence between QUS T-score values and T-score –2.5SD in dual X-ray absorptiometry (DXA) were established. They ranged between –1.63SD and –1.70SD in relation to femoral neck DXA and between –1.22SD and –1.51SD in relation to lumbar spine DXA, depending on age category. In conclusion, the study described here confirmed that QUS measurements at the calcaneus may provide information comparable to DXA examinations at the femoral neck and lumbar spine in postmenopausal women.  相似文献   
4.
Carbon-based quantum dots are widely suggested as fluorescent carriers of drugs, genes or other bioactive molecules. In this work, we thoroughly examine the easy-to-obtain, biocompatible, nitrogen-containing carbonaceous quantum dots (N-CQDs) with stable fluorescent properties that are resistant to wide-range pH changes. Moreover, we explain the mechanism of fluorescence quenching at extreme pH conditions. Our in vitro results indicate that N-CQDs penetrate the cell membrane; however, fluorescence intensity measured inside the cells was lower than expected from carbonaceous dots extracellular concentration decrease. We studied the mechanism of quenching and identified reduced form of β-nicotinamide adenine dinucleotide (NADH) as one of the intracellular quenchers. We proved it experimentally that the elucidated redox process triggers the efficient reduction of amide functionalities to non-fluorescent amines on carbonaceous dots surface. We determined the 5 nm–wide reactive redox zone around the N-CQD surface. The better understanding of fluorescence quenching will help to accurately quantify and dose the internalized carbonaceous quantum dots for biomedical applications.  相似文献   
5.
6.

Background

The G protein-coupled receptor 35 (GPR35), is considered important for nociceptive transmission, as suggested by accumulating evidence. This receptor was discovered in 1998; however, a lack of pharmacological tools prevented a complete understanding of its function and how to exploit it therapeutically. We studied the influence of CXCL17, kynurenic acid and zaprinast on nociceptive transmission in naïve and neuropathic mice. Additionally, we investigated the influence of kynurenic acid and zaprinast on morphine effectiveness in neuropathic pain.

Methods

The chronic constriction injury (CCI) of the sciatic nerve in Swiss mice was performed. The CXCL17, kynurenic acid, zaprinast and morphine were injected intrathecally into naive and CCI-exposed mice at day 14. To evaluate tactile and thermal hypersensitivity, the von Frey and cold plate tests were used, respectively.

Results

Our results have shown, for the first time, that administration of CXCL17 in naïve mice induced strong pain-related behaviours, as measured by von Frey and cold plate tests. Moreover, we demonstrated that kynurenic acid and zaprinast diminished CXCL17-evoked pain-related behaviours in both tests. Kynurenic acid and zaprinast reduced thermal and tactile hypersensitivity developed by sciatic nerve injury and strongly enhanced the effectiveness of morphine in neuropathy.

Conclusions

Our study highlights the importance of GPR35 as a receptor involved in neuropathic pain development. Therefore, these results suggest that the modulation of GPR35 could become a potential strategy for the treatment of neuropathic pain.  相似文献   
7.
Targeting of the TRAIL-DR4/5 pathway was proposed as a promising approach for specific induction of apoptosis in cancer cells. Clinical trials, however, showed inadequate efficiency of TRAIL as a monotherapy. It is a widely held view that the application of multifunctional molecules or combination therapy may lead to substantial improvement. Here, we demonstrate the effectiveness and safety of a novel chimeric protein, AD-O51.4, which is a TRAIL equipped with positively charged VEGFA-derived effector peptides. The study was performed in multiple cancer cell line- and patient-derived xenografts. A pharmacokinetic profile was established in monkeys. AD-O51.4 strongly inhibits tumor growth, even leading to complete long-term tumor remission. Neither mice nor monkeys treated with AD-O51.4 demonstrate symptoms of drug toxicity. AD-O51.4 exhibits a satisfactory half-life in plasma and accumulates preferentially in tumors. The cellular mechanism of AD-O51.4 activity involves both cytotoxic effects in tumor cells and antiangiogenic effects on the endothelium. The presence of DRs in cancer cells is crucial for AD-O51.4-driven apoptosis execution. The TRAIL component of the fusion molecule serves as an apoptosis inducer and a cellular anchor for the effector peptides in TRAIL-sensitive and TRAIL-resistant cancer cells, respectively. The FADD-dependent pathway, however, seems to be not indispensable in death signal transduction; thus, AD-O51.4 is capable of bypassing the refractoriness of TRAIL. AD-O51.4-driven cell death, which exceeds TRAIL activity, is achieved due to the N-terminally fused polypeptide, containing VEGFA-derived effector peptides. The high anticancer efficiency of AD-O51.4 combined with its safety has led to the entry of AD-O51.4 into toxicological studies.  相似文献   
8.
Despite evidence for a difference in total brain volume between dyslexic and good readers, no previous neuroimaging study examined differences in allometric scaling (i.e. differences in the relationship between regional and total brain volumes) between dyslexic and good readers. The present study aims to fill this gap by testing differences in allometric scaling and regional brain volume differences in dyslexic and good readers. Object‐based morphometry analysis was used to determine grey and white matter volumes of the four lobes, the cerebellum and limbic structures in 130 dyslexic and 106 good readers aged 8–14 years. Data were collected across three countries (France, Poland and Germany). Three methodological approaches were used as follows: principal component analysis (PCA), linear regression and multiple‐group confirmatory factor analysis (MGCFA). Difference in total brain volume between good and dyslexic readers was Cohen's d = 0.39. We found no difference in allometric scaling, nor in regional brain volume between dyslexic and good readers. Results of our three methodological approaches (PCA, linear regression and MGCFA) were consistent. This study provides evidence for total brain volume differences between dyslexic and control children, but no evidence for differences in the volumes of the four lobes, the cerebellum or limbic structures, once allometry is taken into account. It also finds no evidence for a difference in allometric relationships between the groups. We highlight the methodological interest of the MGCFA approach to investigate such research issues.  相似文献   
9.
Introduction

With continuously growing number of redo bariatric surgeries (RBS), it is necessary to look for factors determining success of redo-surgeries.

Patients and methods

A retrospective cohort study analyzed consecutive patients who underwent RBS in 12 referral bariatric centers in Poland from 2010 to 2020. The study included 529 patients. The efficacy endpoints were percentage of excessive weight loss (%EWL) and remission of hypertension (HT) and/or type 2 diabetes (T2D).

Results

Group 1: weight regain

Two hundred thirty-eight of 352 patients (67.6%) exceeded 50% EWL after RBS. The difference in body mass index (BMI) pre-RBS and lowest after primary procedure < 10.6 kg/m2 (OR 2.33, 95% CI: 1.43–3.80, p = 0.001) was independent factor contributing to bariatric success after RBS, i.e., > 50% EWL.

Group 2: insufficient weight loss

One hundred thirty of 177 patients (73.4%) exceeded 50% EWL after RBS. The difference in BMI pre-RBS and lowest after primary procedure (OR 0.76, 95% CI: 0.64–0.89, p = 0.001) was independent factors lowering odds for bariatric success.

Group 3: insufficient control of obesity-related diseases

Forty-three of 87 patients (49.4%) achieved remission of hypertension and/or type 2 diabetes. One Anastomosis Gastric Bypass (OAGB) as RBS was independent factor contributing to bariatric success (OR 7.23, 95% CI: 1.67–31.33, p = 0.008), i.e., complete remission of HT and/or T2D.

Conclusions

RBS is an effective method of treatment for obesity-related morbidity. Greater weight regain before RBS was minimizing odds for bariatric success in patients operated due to weight regain or insufficient weight loss. OAGB was associated with greater chance of complete remission of hypertension and/or diabetes.

Graphical abstract
  相似文献   
10.
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