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Purpose: The medicinal plant Ipomoea aquatica belonging to convulvulaceae family is an effective natural herb for treatment of various ailments and possesses effective anticancer activity. The aim of the work is to characterize a secondary metabolite merromoside (a resin glycoside) for anti-breast cancer activity through down regulation of ROS species. Methods: The Extract of the whole plant has been prepared by maceration method using 50%v/v ethanol in distilled water to get a hydroalcoholic extract. The phytochemical evaluation reveals that the active secondary metabolite was isolated by using column chromatographic technique. The isolated compound was evaluated for its anticancer properties through invitro method such as 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay on Michigan Cancer Foundation-7 Cell lines. The purity and structural characterization were done by high-performance thin layer chromatography, Fourier Transform Infrared Spectroscopy, Proton and13C Nuclear Magnetic Resonance spectroscopy and Liquid Chromatography–Mass Spectrometry. Results: The isolated compound (W04) from the derived extract showed Rf value of 0.79 that showed IC50 of 182.8μg/ml. The chemical structure of W04 has been confirmed as [4,5-dihydroxy-6-[5-hydroxy-2-methyl-4-(2-methylpropanoyloxy)-6-[(24,25,26-trihydroxy-5,23-dimethyl-9-oxo-19-pentyl-2,4,8,20,22-pentaoxatricyclo[19.2.2.13,7]hexacosan-6-yl)oxy]oxan-3-yl]oxy-2-methyloxan-3-yl] 2-methyl propanoate with the molecular weight of 979.15268. The isolated compound merromoside from hydroalcoholic extract of Ipomoea aquatica has been evaluated for anti-breast cancer properties. The down regulation of ROS species will prevent reverse signalling and angiogenesis. This indicates that merromoside will overcome MDR in breast cancer especially DOX-resistant.  相似文献   
3.
Blood transfusion, using the safest conventional blood bioproducts, is an irreplaceable part of substitution therapy. It is considered the most essential supportive clinical intervention aimed to restore the health of patients in need. Nevertheless, numerous unresolved problems are still associated with current blood substitution therapy. To alleviate our dependency on blood donors, many investigators have been focusing on the quest for stem cell-derived blood cells in line with major developments in the field of regenerative medicine. The main objective is to provide a safe and highly standardized universal cultured red cell concentrate [CRBC] for all clinical applications, regardless of blood groups. Currently, we are close to overcoming some of the main obstacles in culturing cells. This concise report is a prelude to the immortalized cell lines that are ready for in vivo clinical trials. It is only through the sharing of experimental ideas and knowledge-based strategies that we will be able to achieve such an enormous task and better understand ‘’the one for all concept’’ of CRBCs and their universal usage in all clinical settings.  相似文献   
4.
CT三维重建技术已经广泛应用于骨折诊断及其分型。基于CT三维重建的骨折地图绘制技术,通过绘制骨折模型来直观展现骨折线的形态学,包括骨折线的起止、走行、骨折面积等。骨折地图绘制技术为骨折诊断、骨折分型、治疗方案选择、手术内固定物设计、骨折好发部位统计、骨折标准化模型制定均提供了一个全新的方法。本文将回顾目前国内外包括对于肩胛骨骨折、胫骨远端骨折、尺骨冠状突骨折、胫骨平台骨折、桡骨小头骨折、股骨转子间外侧壁骨折、髋臼四边体骨折等骨折地图的研究进展,归纳总结了以上各个骨折模型的骨折好发部位及骨折地图绘制技术在骨折分型等方面的应用,并探讨骨折地图的临床应用前景及骨折地图绘制技术存在的问题等。  相似文献   
5.
Adaptation of osteology and myology lead to the formation of hydrofoil foreflippers in Cheloniidae (all recent sea turtles except Dermochelys coriacea) which are used mainly for underwater flight. Recent research shows the biomechanical advantages of a complex system of agonistic and antagonistic tension chords that reduce bending stress in bones. Finite element structure analysis (FESA) of a cheloniid humerus is used to provide a better understanding of morphology and microanatomy and to link these with the main flipper function, underwater flight. Dissection of a Caretta caretta gave insights into lines of action, that is, the course that a muscle takes between its origin and insertion, of foreflipper musculature. Lines of action were determined by spanning physical threads on a skeleton of Chelonia mydas. The right humerus of this skeleton was micro-CT scanned. Based on the scans, a finite element (FE) model was built and muscle force vectors were entered. Muscle forces were iteratively approximated until a uniform compressive stress distribution was attained. Two load cases, downstroke and upstroke, were computed. We found that muscle wrappings (m. coracobrachialis magnus and brevis, several extensors, humeral head of m. triceps) are crucial in addition to axial loading to obtain homogenous compressive loading in all bone cross-sections. Detailed knowledge on muscle disposition leads to compressive stress distribution in the FE model which corresponds with the bone microstructure. The FE analysis of the cheloniid humerus shows that bone may be loaded mainly by compression if the bending moments are minimized.  相似文献   
6.

Background

Central vein catheter (CVC) placement using the modified Seldinger technique is a common procedure in the emergency department, but can be time consuming due to the multiple pieces of equipment included in central line kits and the number of steps in the procedure. Preassembled devices combine a needle, guidewire, dilator, and sheath into one unit and potentially simplify the process and reduce time required for CVC placement using the accelerated Seldinger technique.

Objective

Our aim was to evaluate whether the use of combination central line devices and the accelerated Seldinger technique will reduce the time required to place a CVC and increase the ease of the procedure.

Methods

This two-arm randomized crossover study comparing the accelerated Seldinger technique to the modified Seldinger technique was performed in a simulation setting. Subjects were selected from among emergency physicians, emergency medicine residents, interns, physician assistants, and medical students. Subjects were timed using the modified and accelerated Seldinger techniques. Ease of use and satisfaction data were collected after both procedures.

Results

The use of the accelerated Seldinger technique with a combination CVC device was significantly faster compared to the modified Seldinger technique with a standard CVC kit. Procedure time was reduced by 35% (p = 0.001), and ease of use was increased by 7% (p = 0.046), without any increase in errors.

Conclusions

In the simulated setting, the accelerated Seldinger technique using combination CVC devices is a faster and easier method for CVC placement compared to the modified Seldinger technique.  相似文献   
7.
ObjectiveTo evaluate the efficacy of topical vibratory stimulation for reducing pain during trigger point injection (TPI).DesignDouble-blind randomized placebo-controlled clinical trial.SettingTertiary care university hospital.ParticipantsA total of 136 participants were randomly recruited from among patients with myofascial pain syndrome who were scheduled for TPI. Of these, 65 were excluded because they met the exclusion criteria, and 11 because they refused to participate. Finally, 60 participants were enrolled. No participants dropped out of the study.InterventionParticipants were randomly assigned to the vibration group or control group. TPI was performed with 0.5% lidocaine using a 25-gauge needle. A vibrator was applied to the popliteal fossa for 3 to 5 seconds prior to and during TPI to the gastrocnemius; 100-Hz vibration was turned on for the vibration group and turned off for the control group.Main Outcome MeasuresPain intensity during TPI was assessed using a 100-mm visual analog scale (VAS) as a primary outcome, and participant satisfaction and preference for repeated use were measured using 5-point Likert scales as a secondary outcome. These parameters were evaluated immediately after TPI. The primary outcome was evaluated using analysis of covariance and secondary outcome using the Mann-Whitney U test.ResultsVAS scores for pain during TPI were significantly lower in the vibration group (30.30; 95% confidence interval [CI], 22.65-39.26) compared with the control group (47.58; 95% CI, 38.80-56.52; F=7.74; P< .01). The mean difference in VAS scores between the 2 groups was 17.27 (95% CI, 5.24-29.30). Participant satisfaction and preference for repeated use were significantly higher in the vibration group than in the control group (P<.05). No participant showed any side effects.ConclusionTopical vibratory stimulation significantly decreased pain during TPI of the gastrocnemius.  相似文献   
8.
Background: Betel quid chewing is more common among the older generation in rural areas of Malaysia. Oral cancer in Asia has been associated with the habit of chewing betel quid and areca nut. Objective:  This study aims to investigate the cytotoxic effects of betel quid and areca nut extracts on the fibroblast (L929), mouth-ordinary-epithelium 1 (MOE1) and oral squamous cell carcinoma (HSC-2) cell lines. Methods: L929, MOE1 and HSC-2 cells were treated with 0.1, 0.2 and 0.4 g/ml of betel quid and areca nut extracts for 24, 48 and 72 h. MTT assay was performed to assess the cell viability. Results: Both extracts, regardless of concentration, significantly reduced the cell viability of L929 compared with the control (P<0.05). Cell viability of MOE1 was significantly enhanced by all betel quid concentrations compared with the control (P<0.05). By contrast, 0.4 g/ml of areca nut extract significantly reduced the cell viability of MOE1 at 48 and 72 h of incubation. Cell viability of HSC-2 was significantly lowered by all areca nut extracts, but 0.4 g/ml of betel quid significantly increased the cell viability of HSC-2 (P<0.05). Conclusion: Areca nut extract is cytotoxic to L929 and HSC-2, whereas the lower concentrations of areca nut extract significantly increased the cell viability of MOE1 compared to the higher concentration and control group. Although betel quid extract is cytotoxic to L929, the same effect is not observed in MOE1 and HSC-2 cell lines. Further investigations are needed to clarify the mechanism of action.  相似文献   
9.
【摘要】 目的 研究A型肉毒毒素治疗眉间纹引起的皮肤及其下肌层的厚度改变。方法 收集北京协和医院2017年8月至2018年2月注射A型肉毒毒素治疗的26例中重度眉间纹受试者,于注射前及注射后4周、16周,采用50 MHz高频超声检测注射部位皮肤的真皮层厚度,20 MHz高频超声检测皮肤全层和肌层厚度。采用单组重复测量资料的方差分析、配对t检验及Bonferroni法比较受试者注射治疗前后3个时间点超声检测的组织厚度。结果 注射前,真皮层、皮肤全层和肌层厚度分别为(2.01 ± 0.48)、(4.32 ± 0.73)、(4.51 ± 0.67) mm。注射前、注射后4及16周真皮层厚度差异无统计学意义(F = 1.94,P = 0.199),而皮肤全层厚度、肌层厚度差异均有统计学意义(F = 6.28、24.19,P = 0.020、 < 0.001)。与注射前相比,注射后4周皮肤全层厚度显著增加(4.88 ± 0.93 mm,t = 3.72,P = 0.004),而肌层厚度显著降低(3.82 ± 0.79 mm,t = 4.65,P = 0.001)。与注射前和注射后4周相比,注射后16周时皮肤全层厚度(4.61 ± 0.73 mm)和肌层厚度(4.38 ± 0.90 mm)差异均无统计学意义(均P > 0.0167)。结论 注射A型肉毒毒素可改变皮下组织和肌层厚度,高频超声可用于A型肉毒毒素注射治疗眉间纹的疗效评价及随访。  相似文献   
10.
The present investigations attempted to assess the diagnostic accuracy of commercially available surface electromyography (sEMG) and kinesiography (KG) devices for myofascial pain of jaw muscles. Thirty-six (n = 36) consecutive patients with a research diagnostic criteria for temporomandibular disorders (RDC/TMD) axis I diagnosis of myofascial pain and an age- and sex-matched group of 36 TMD-free asymptomatic subjects underwent sEMG and KG assessments to compare EMG parameters of the masseter and temporalis muscles as well as the jaw range of motion and the interarch freeway space. EMG data at rest were not significantly different between myofascial pain patients and asymptomatic subjects, while the latter achieved significantly higher levels of EMG activity during clenching tasks. Symmetry of muscle activity at rest and during clenching tasks, KG parameters of jaw range of motion and the measurement of the interarch vertical freeway did not differ between groups. Receiver operating characteristics curve analysis showed that, except EMG parameters during clenching tasks, all the other outcome sEMG and KG measures did not reach acceptable levels of sensitivity and specificity, with a 30·6-88·9% percentage of false-positive results. Therefore, clinicians should not use sEMG and KG devices as diagnostic tools for individual patients who might have myofascial pain in the jaw muscles. Whether intended as a stand-alone measurement or as an adjunct to making clinical decisions, such instruments do not meet the standard of reliability and validity required for such usage.  相似文献   
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