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61.
We investigated morphometric brain changes in patients with Parkinson's disease (PD) that are associated with balance training. A total of 20 patients and 16 healthy matched controls learned a balance task over a period of 6 weeks. Balance testing and structural magnetic resonance imaging were performed before and after 2, 4, and 6 training weeks. Balance performance was re-evaluated after ∼20 months. Balance training resulted in performance improvements in both groups. Voxel-based morphometry revealed learning-dependent gray matter changes in the left hippocampus in healthy controls. In PD patients, performance improvements were correlated with gray matter changes in the right anterior precuneus, left inferior parietal cortex, left ventral premotor cortex, bilateral anterior cingulate cortex, and left middle temporal gyrus. Furthermore, a TIME × GROUP interaction analysis revealed time-dependent gray matter changes in the right cerebellum. Our results highlight training-induced balance improvements in PD patients that may be associated with specific patterns of structural brain plasticity. In summary, we provide novel evidence for the capacity of the human brain to undergo learning-related structural plasticity even in a pathophysiological disease state such as in PD.  相似文献   
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Neurocritical Care - Despite the tremendous impact of swallowing disorders on outcome following ischemic stroke, little is known about the incidence of dysphagia after subarachnoid hemorrhage (SAH)...  相似文献   
64.
Magnesium may contribute to the immune response during and after SARS-CoV-2 infection by acting as a cofactor for immunoglobulin production and other processes required for T and B cell activity. Considering magnesium as a recommended dietary supplement during pregnancy and the possible role of magnesium deficiency in COVID-19 and its complications, the current study sought to determine the effect of magnesium and magnesium-containing nutritional supplements on the immune response following SARS-CoV-2 infection in pregnant women, as well as to observe differences in pregnancy outcomes based on the supplements taken during pregnancy. The study followed a cross-sectional design, where patients with a history of SARS-CoV-2 infection during their pregnancy were surveyed for their preferences in nutritional supplementation and their profile compared with existing records from the institutional database. A cohort of 448 pregnant women with COVID-19 during 22 months of the pandemic was assembled, out of which 13.6% took a magnesium-only supplement, and 16.5% supplemented their diet with a combination of calcium, magnesium, and zinc. Around 60% of patients in the no-supplementation group had the SARS-CoV-2 anti-RBD lower than 500 U/mL, compared with 50% in those who took magnesium-based supplements. A quantity of magnesium >450 mg in the taken supplements determined higher levels of antibody titers after COVID-19. Low magnesium dosage (<450 mg) was an independent risk factor for a weak immune response (OR-1.25, p-value = 0.003). The observed findings suggest supplementing the nutritional intake of pregnant women with magnesium-based supplements to determine higher levels of SARS-CoV-2 anti-RBD antibodies, although causality remains unclear.  相似文献   
65.
In this work, cotton textile materials were impregnated by immersion with three different nanocomposites: Ag/chitosan, Ag/polyvinylpyrrolidone, and ZnO/polyvinylpyrrolidone and irradiated with a 60Co gamma source. After the nanoparticles impregnation, the cotton materials were irradiated in a dry and wet state at 5 and 20 kGy radiation doses. The following methods were used for the characterization of the obtained cotton materials to reveal the modification of the textile materials: Fourier transform infrared-attenuated total reflection spectroscopy (FTIR-ATR) and thermogravimetry (TG). The obtained materials have good antibacterial properties. The microbiological tests have shown the best material results for the gamma irradition and Ag nanoparticles combined treatment. The objective was to create a more environmentally friendly approach for textile functionalization by eliminating toxic chemicals-based technology and replacing it with the eco-friendlier gamma technology.  相似文献   
66.
Globally, COVID-19 vaccines are currently being used to prevent transmission and to reduce morbidity and death associated with SARS-CoV-2 infection. Current research reveals that vaccines such as BNT162b2 and Ad26.COV2.S are highly immunogenic and have high short-term effectiveness for most of the known viral variants. Clinical trials showed satisfying results in the general population, but the reluctance in testing and vaccinating pregnant women left this category with little evidence regarding the safety, efficacy, and immunogenicity following COVID-19 vaccination. With the worldwide incidence of COVID-19 remaining high and the possibility of new transmissible SARS-CoV-2 mutations, data on vaccination effectiveness and antibody dynamics in pregnant patients are critical for determining the need for special care or further booster doses. An observational study was developed to evaluate pregnant women receiving the complete COVID-19 vaccination scheme using the BNT162b2 and Ad26.COV2.S, and determine pregnancy-related outcomes in the mothers and their newborns, as well as determining adverse events after vaccination and immunogenicity of vaccines during four months. There were no abnormal findings in pregnancy and newborn characteristics comparing vaccinated versus unvaccinated pregnant women. COVID-19 seropositive pregnant women had significantly higher spike antibody titers than seronegative patients with similar characteristics, although they were more likely to develop fever and lymphadenopathy following vaccination. The same group of pregnant women showed no statistically significant differences in antibody titers during a 4-month period when compared with case-matched non-pregnant women. The BNT162b2 and Ad26.COV2.S vaccines are safe to administer during the third trimester of pregnancy, while their safety, efficacy, and immunogenicity remain similar to those of the general population.  相似文献   
67.
In recent years, the shipbuilding industry has experienced a growing demand for tighter control and higher strength requirements in thick steel plate welding. Electro-gas welding (EGW) is a high heat input welding method, widely used to improve the welding efficiency of thick plates. Modelling the EGW process of thick steel plates has been challenging due to difficulties in accurately depicting the heat source path movement. An EGW experiment on 30 mm thickness E36 steel plates was conducted in this study. A semi-ellipsoid heat source model was implemented, and its movement was mathematically expressed using linear, sinusoidal, or oscillate-stop paths. The geometry of welding joints, process variables, and steel composition are taken from industrial scale experiments. The resulting thermal evolutions across all heat source-path approaches were verified against experimental observations. Practical industrial recommendations are provided and discussed in terms of the fusion quality for E36 steel plates with a heat input of 157 kJ/cm. It was found that the oscillate-stop heat path predicts thermal profile more accurately than the sinusoidal function and linear heat path for EGW welding of 30 mm thickness and above. The linear heat path approach is recommended for E36 steel plate thickness up to 20 mm, whereas maximum thickness up to 30 mm is appropriate for sinusoidal path, and maximum thickness up to 35 mm is appropriate for oscillate-stop path in EGW welding, assuming constant heat input.  相似文献   
68.
Knowledge regarding the influence of the microbial community in cancer promotion or protection has expanded even more through the study of bacterial metabolic products and how they can modulate cancer risk, which represents an extremely challenging approach for the relationship between intestinal microbiota and colorectal cancer (CRC). This review discusses research progress on the effect of bacterial dysbiosis from a metabolic point of view, particularly on the biochemical mechanisms of butyrate, one of the main short chain fatty acids (SCFAs) with anti-inflammatory and anti-tumor properties in CRC. Increased daily intake of omega-3 polyunsaturated fatty acids (PUFAs) significantly increases the density of bacteria that are known to produce butyrate. Omega-3 PUFAs have been proposed as a treatment to prevent gut microbiota dysregulation and lower the risk or progression of CRC.  相似文献   
69.
Objective

This study aimed to present a new possibility to create radio-opaque implant material for craniomaxillofacial reconstruction.

Materials and methods

The test disks made of the own compound of polyethylenes with addiction of 2, 4, and 6 % of weight TiO2 was investigated for cytotoxicity [each group 15 disks respectively]. Next, computed tomography of the disks was performed in environment of muscle and fat. Hardness, tensile modulus and strength, and compressive modulus and strength were tested too.

Results

Deterioration of mechanical properties of the composites containing titanium dioxide was observed [hardness, tensile modulus and strength, compressive modulus and strength, respectively: 56.7 ± 1.6 shore D, 354 ± 52, 22.5 ± 1.3, 21.8 ± 1.1, and 2995 ± 327 MPa as addiction of 2 % TiO2; 52.0 ± 0.9 shore D, 347 ± 66, 18.0 ± 0.7, 14.2 ± 0.9, and 1396 ± 477 MPa as 4 % TiO2; 51.3 ± 1.3 shore D, 316 ± 9, 17.4 ± 0.2, 13.6 ± 0.6, and 1100 ± 144 MPa as 6 % TiO2 added]. The test disks revealed no cytotoxicity effect on human osteoblasts. The new material presents mild radio-opacity which was enough to observe the implant in relation to fat and muscle, but with no visible effect of beam hardening.

Conclusion

In view of the performed tests, the polyethylene enriched by titanium dioxide seems to be a proper material to consider manufacturing of craniomaxillofacial implants.

Clinical relevance

Maxilloafacial surgery is still looking for new implantologic materials. The proposed one is a new way to manufacture an implant visible in computed tomography which does not interfere with its shape in radiological examination and makes it possible to observe the surrounding soft tissues.

  相似文献   
70.
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