Lasting improvements in left spatial neglect following a protocol combining neck-muscle vibration and voluntary arm movements: a case-study

Purpose: Beyond promising experimental results of sensory passive stimulations in spatial cognition disorders, some questions still remain regarding interests of these stimulations during the daily activities in neglect. The aim of this case-study was to evaluate the effects of a protocol combining left neck-muscle vibration with daily simple movements, like arm pointing movements, on perceptivo-locomotor deficits in a left spatial neglect patient.

Materials and methods: Two neuropsychological tests, one subjective straight-ahead pointing (SSA) test and one wheelchair navigation test were carried out before the combination protocol, immediately after, 1?h later, and 24?h later.

Results: The results showed a reduction of neglect spatial bias following the protocol lasted at least 24?h in all the tests (except for the SSA test due to the unavailability of the pointing device).

Conclusions: The range of improvements in the symptoms of spatial neglect suggests that this therapeutic intervention based on the combining neck-muscle vibration to voluntary arm movements could be a useful treatment for this condition. One of future investigation axes should be the development of a vibratory tool in order to facilitate the combining this proprioceptive stimulation to daily activities.

• Implications for rehabilitation

• Spatial neglect is a perplexing neuropsychological syndrome, affecting different domains of spatial cognition and impacting also the functional domain.

• The treatments based on neck-muscle vibration are simple to use, non-invasive and requires none active participation of patient.

• A therapeutic intervention based on the combining left neck-muscle vibration and voluntary arm movements in a left-spatial-neglect show a lasting reduction of symptoms especially in daily activities.

• The combination of treatments based on the Bottom–Up approach opens innovative perspectives in rehabilitation.

     

Vibratory stimulus to the masseter muscle impairs the oral fine motor control during biting tasks

PurposeTo investigated the effect of vibratory stimulus on masseter muscles during oral fine motor biting tasks.MethodsSixteen healthy individuals (age: 24.5 ± 2.4 years) participated in experiment I during which the participants were asked to “hold and split” half a roasted peanut placed on a force transducer with their front teeth. The participant performed ten series with ten trials of the “hold and split” behavioral task while vibratory stimulus was applied on the masseter muscle every alternate series. Further, fourteen participants participated (age: 25.2 ± 4.8 years) in experiment II during which they performed a series each of the behavioral task at baseline, an adjusted baseline without and with vibration as well as with and without visual feedback. Hold and split forces along with the variability of hold force and duration and force rate during the split were measured.ResultsThe results of the study showed an increase in the magnitude of the hold force (P = 0.002), force rate during the split (P < 0.001) and a significant decrease in the duration of split (P < 0.001) due to the vibratory stimulus. However, there was no significant effect of the vibratory stimulus on the variability of hold forces (P = 0.879) or mean split force (P = 0.683) during the “hold and split” behavioral task. The results of experiment II also showed an increase in hold force due to the vibratory stimulus (P < 0.001).ConclusionsVibratory stimulus to the masseter muscles impairs the oral force control during a standardized biting task and provide further insight into the sensorimotor regulation of the masticatory system.     

全身振动训练联合正弦交变电磁场对去卵巢骨质疏松大鼠骨密度、骨代谢指标的影响研究

目的探讨全身振动训练联合正弦交变电磁场对去卵巢骨质疏松大鼠骨密度、骨代谢、骨生物力学性能的影响。方法将100只大鼠随机分为切除卵巢组和对照组,分别进行卵巢切除术和假手术,大鼠进行6周恢复,恢复后将造模成功的切除卵巢大鼠随机分为模型组(MO组)、全身振动训练组(W组)、正弦交变电磁场组(S组)、全身振动训练+正弦交变电磁场组(WS组),对照组列为假手术组(SO组),进行为期16周干预,干预结束后对大鼠进行骨密度、骨代谢、骨生物力学性质的检测。结果16周干预完成后,MO组、S组大鼠体质量显著高于SO组、W组、WS组大鼠(P0. 05); W组、WS组、SO组大鼠骨密度指标、血清雌二醇浓度指标明显高于大鼠MO组(P0. 05); SO组大鼠血清雌二醇浓度指标明显高于S组、W组、WS组(P0. 05); M组大鼠血清OC、ALP浓度明显高于SO组、W组、S组、WS组大鼠(P0. 05);尿液DPD/Cre、Ca/Cre、P/Cre浓度方面,M组大鼠明显高于SO组、W组、S组、WS组大鼠(P0. 05)。SO组、W组、S组、WS组大鼠股骨最大载荷和弹性模型明显高于MO组大鼠(P0. 05)。SO组、W组、S组、WS组大鼠股骨断裂载荷组间无明显差异(P0. 05); SO组、W组、S组、WS组大鼠股骨弹性模量明显高于MO组大鼠(P0. 05)。SO组大鼠股骨弹性模量明显高于S组大鼠(P0. 05),但与W组、WS组大鼠没有明显差异(P0. 05)。L4椎体压缩试验,SO组、W组、S组、WS组大鼠股骨最大载荷和弹性模型明显高于MO组大鼠(P0. 05)。SO组大鼠高于S组、W组,差异有统计学意义(P0. 05),但与WS组大鼠没有明显差异(P0. 05)。结论全身振动训练、正弦交变电磁场、全身振动训练联合正弦交变电磁场3种干预方式施用于去卵巢骨质疏松大鼠均能提升骨密度、抑制骨吸收、平衡骨代谢、改善骨骼结构力学和材料力学性能。而全身振动训练联合正弦交变电磁场能的治疗效果优于单纯使用全身振动训练或正弦交变电磁场,在临床应用中有一定推广价值。     

Preliminary Risk assessment for Acrylamide and Peripheral Neuropathy

Acrylamide (ACM) is a high-volume industrial chemical with diverse uses in manufacturing, construction and laboratory research. ACM is a well-established neurotoxic agent causing peripheral neuropathy with impairment in the arms and legs of exposed workers, most thoroughly studied in Swedish tunnel workers exposed to ACM grouting. A quantitative risk assessment was performed to assess ACM risk to workers. Using data from a published paper investigating peripheral neuropathies in Chinese chemical workers, estimates of exposure response for vibration perception threshold and nerve conduction velocities were calculated, based on hemoglobin adducts and air concentrations as exposure metrics. The benchmark dose procedure was applied in order to calculate excess risks of impairment, defined as adverse performance exceeding the 95^th percentile in unexposed populations, at various concentrations of airborne ACM exposure. Under the assumptions in this risk assessment, after three years of inhalation exposure at 0.3 mg/m³, the excess attributable impairment manifest in vibration perception and nerve conduction velocity is estimated to occur in 1-2% of workers. For 10 years at 0.3 mg/m³ ACM inhalation (equivalent to 3 years at 1.0 mg/m³) the excess prevalence of impairment would be 2-14% of workers, assuming the effect continues to accrue linearly in time. Using published data, the risks of impairment from peripheral neuropathy attributable to exclusively airborne ACM exposure can be predicted for exposure periods less than 10 years. The risks associated with dermal and airborne ACM exposures can be estimated by characterizing working process environments using ACM Hb-adduct levels and possibly monitored with urinary biomarkers.     

根管口直径及纤维桩长度对纤维桩振动频率和抗折性的影响

目的 探讨根管口直径及纤维桩长度对纤维桩振动频率和体外抗折性的影响.方法 选择2012年6月～2013年10月我院口腔外科门诊正畸治疗中拔除的78颗单根管前磨牙,随机均分为A、B两组,每组39颗.A组试件的纤维桩长度为8 mm,根管口直径分别为1.0、1.3、1.6 mm,B组试件的根管口直径为1.3 mm,纤维桩长度分别为8、10、12 mm.A组给予外激励作用并采集信号,经傅里叶转换,将加速度信号转变为振动频率;B组以压力测试仪测量样本瞬间折裂时的作用力数值.比较不同根管口直径对纤维桩振动频率和纤维桩长度对牙齿抗折性的影响.结果 A组纤维桩振动频率分别为(514.63±3.94)Hz、(469.88±4.39)Hz、(203.86±5.13)Hz,组间具有显著性差异(P＜0.01);B组抗折性的平均作用力分别为(892.63±42.81)N、(1197.63±54.62)N、(1282.33±52.82)N,组间抗折性具有显著性差异(P＜0.01).结论 根管口直径与纤维桩振动频率具有相关性,可反映纤维桩的粘结状态;在进行牙根管治疗时,预备纤维桩的长度以近似等于或略高于牙冠的长度为宜.     

纤支镜肺泡灌洗联合振荡排痰仪治疗老年COPD合并肺癌的疗效观察

目的探讨纤支镜肺泡灌洗联合振荡排痰仪治疗老年慢性阻塞性肺疾病(COPD)合并肺癌的效果。方法选取2019年1月至2019年10月于解放军联勤保障部队第九九〇医院接受治疗的86例老年COPD合并肺癌患者作为研究对象,随机分为2组,每组43例,对照组在对症治疗基础上采用震荡排痰仪辅助排痰,观察组在此基础上联合纤支镜进行肺泡灌洗治疗,对比两组有效率、炎症因子水平、恢复时间和住院时间。结果治疗10 d后,观察组有效率明显高于对照组,炎症因子水平低于对照组,恢复时间和住院时间短于对照组(P<0.05)。结论纤支镜肺泡灌洗联合振荡排痰仪治疗老年COPD合并肺癌效果确切,能显著改善患者肺不张状况,降低炎症水平,缩短治疗时间和住院时间。     

Evaluation of Spironolactone Solid Dispersions Prepared by Co-Spray Drying With Soluplus® and Polyvinylpyrrolidone and Influence of Tableting on Drug Release

Solid dispersions of spironolactone with Soluplus^® and polyvinylpyrrolidone were prepared by spray drying according to a mixture experimental design and evaluated for moisture content, particle size, drug solubility, crystallinity (powder X-ray diffraction and differential scanning calorimetry), and physicochemical interactions (Fourier-transform infrared spectroscopy, Raman). In vitro dissolution was evaluated for the spray dried product itself and after compression into tablets, and prediction models were derived using multiple linear regression analysis. The spray dried products consisted of amorphous drug, indicated by the absence of crystalline powder X-ray diffraction peaks. Amorphization and interactions impacted changes in the Fourier-transform infrared spectroscopy spectra in the ranges 2900-3000 cm^?1 (C-H) and 1600-1800 cm^?1 (C=O) and caused merging at 1690 cm^?1 (C=O of lactone) and 1670 cm^?1 (C=O of thioacetyl group). In the Raman spectra, amorphization and interactions resulted in disappearance of peak at 1690 cm^?1 (C=O) and merging of peaks at 582 and 600 cm^?1 (C-S). Hydrogen bonding between the thioacetyl group of the drug with the hydroxyl groups of Soluplus^® caused marked suppression of the peak at 1190 cm^?1 (R-C(=O)-S vibration). Amorphization and interactions resulted in improved solubility and dissolution which was greatest for drug/Soluplus^® ratio 1:4 and was also demonstrated in the corresponding tablets.     

Effect of Dynamic Loading Methods on Cement Film Thickness In Vitro

Purpose Reduced cement film thicknesses can improve crown seating and decrease marginal discrepancies. Improved marginal adaptation has the potential to reduce plaque accumulation, periodontal disease, and cement dissolution. Studies have indicated that dynamic seating methods can reduce seating discrepancies associated with zinc phosphate and resin cements. However, other types of cements and other dynamic techniques have not yet been studied or compared, nor has the mechanism for improved seating been fully explained. Therefore, the purpose of this study was to investigate the effect of a variety of loading methods on the film thicknesses of current types of crown and fixed partial denture cements compressed between glass plates. Materials and Methods This study investigated the effect of three dynamic loading methods on film thickness of six representative fixed prosthodontic cements. These included zinc phosphate, resin-modified glass ionomer, encapsulated glass ionomer, adhesive composite resin, composite resin, and polycarboxylate. The method was derived from American Dental Association specifications for cement film thickness. In control groups, the cements were placed between two glass plates and statically loaded with a 15-kg weight. The test groups were initially similarly loaded, and then for 30 seconds further subjected to simulated repeated patient opening and closing, vibrations from an electromallet, or an ultrasonic device. Results Mean film thicknesses ranged from 7.4 μm for polycarboxylate/ultrasound up to 40.3 μm for composite resin/static. Two-way analysis of variance revealed that the effects of material type and cementation method and their interaction all significantly affected film thickness (P < .0001). Multiple range analysis showed that dynamic methods were generally superior to static loading and that the ultrasonic method was the best overall. Conclusions The different dynamic loading methods all significantly decreased cement film thicknesses between glass plates. The ultrasonic method was the most effective. The type of cement used also influenced film thickness. Composite resins were more affected than other materials.     

Effects of pulsed electromagnetic field vibration on tooth movement induced by magnetic and mechanical forces: a preliminary study

BACKGROUND: This study was designed to determine whether or not high-frequency and low-magnitude vibration affects orthodontic tooth movement caused by magnetic or/and mechanical forces. METHODS: Forty-four 7-week-old Wistar rats were randomly divided into four groups, with each group further divided into experimental and control subgroups. Neodymium-Iron-Boron (Nd-Fe-B) magnets and Sentalloy closed coil springs were placed between maxillary or mandibular first molars and incisors to activate tooth movement. The animals of experimental subgroups were exposed to the vibration induced by pulsed electromagnetic fields (PEMF) whilst the control subgroups were under normal atmosphere. The experiment lasted for 14 days and all of the animals were sacrificed for examination. The changes in the space between the molar and incisor were measured to indicate the amount of tooth movement. RESULTS: The coil springs, either with sham or active magnets, move molar much more than magnets alone, regardless of absence or presence of PEMF (p < 0.001). Under PEMF, the coil spring moved significantly more amount of tooth movement than that of coil-magnet combination (p < 0.01), as did the magnets compared to sham magnets (p < 0.019). Under a non-PEMF scenario, there was no significant difference in tooth movement between coil spring and coil-magnets combination, nor was there difference between magnets and sham magnets. CONCLUSIONS: It is suggested that the PEMF-induced vibration may enhance the effect of mechanical and magnetic forces on tooth movement.