RMS

RMS
  • 文章类型: Case Reports
    在肺泡横纹肌肉瘤(ARMS)中经常观察到Coagulopathies最常见的表现是弥散性血管内凝血(DIC)。然而,纤溶亢进是一种独特但经常重叠且可能危及生命的凝血障碍亚组,需要特定的诊断和治疗方法.
    临床医生如何识别纤溶亢进,对治疗有什么影响?
    本病例报告描述了一名25岁男性患者,在开始化疗一周后出现持续性肉眼血尿。进行了全面的凝血检查,包括血小板计数的评估,凝血酶原时间,活化部分凝血活酶时间,纤维蛋白原,D-二聚体,和纤维蛋白降解产物。管理包括纤维蛋白原的补充和抗纤维蛋白溶解剂的使用。
    认识到ARMS患者的纤溶亢进对于适当的管理至关重要。临床医生应高度怀疑存在严重凝血异常的ARMS患者的纤溶亢进,尤其是前列腺受累或接受化疗的患者。在原发性纤溶亢进的情况下,抗纤溶药可以考虑,而它们通常在DIC中禁忌。
    UNASSIGNED: Coagulopathies are frequently observed in alveolar rhabdomyosarcoma (ARMS), with disseminated intravascular coagulation (DIC) being the most common presentation. However, hyperfibrinolysis represents a distinct but often overlapping and potentially life-threatening subset of coagulation disorders that requires specific diagnostic and management approaches.
    UNASSIGNED: How can clinicians identify hyperfibrinolysis and what are the implications for management?
    UNASSIGNED: This case report describes a 25-year-old man with metastatic ARMS arising from the prostate who developed persistent gross hematuria one week after initiating chemotherapy. A comprehensive coagulation workup was performed, including assessment of platelet count, prothrombin time, activated partial thromboplastin time, fibrinogen, D-dimer, and fibrin degradation products. Management included repletion of fibrinogen and the use of anti-fibrinolytic agents.
    UNASSIGNED: Recognizing hyperfibrinolysis in ARMS patients is crucial for appropriate management. Clinicians should maintain a high index of suspicion for hyperfibrinolysis in ARMS patients presenting with severe coagulation abnormalities, particularly those with prostatic involvement or undergoing chemotherapy. In cases of primary hyperfibrinolysis, antifibrinolytic agents may be considered, whereas they are generally contraindicated in DIC.
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  • 文章类型: Journal Article
    本研究的重点是设计和合成两种新型的配位聚合物(CPs),命名为1和2,具有优异的荧光性能。通过X射线单晶衍射对其结构进行了表征,揭示了这两种材料都表现出良好的荧光性能,表明它们作为荧光检测工具的潜力。此外,选择1与壳聚糖(CS)组合,从而成功制造出可生物降解且无毒的高效药物载体,称为CS-1@顺铂。该载体具有大的表面积和良好的溶解性,使药物持续释放到靶细胞。鉴于CXC基序趋化因子受体4型(CXCR4)是在横纹肌肉瘤(RMS)细胞和组织中高表达的关键标记基因,选择RMS作为测试的生物模型。结果证明CS-1@顺铂通过显著抑制CXCR4的表达而有效抑制RMS细胞的侵袭力。因此,该系统在RMS治疗中显示出巨大的应用潜力,生物识别技术,和药物输送,特别是通过抑制关键标记基因CXCR4靶向RMS的独特优势。
    This study focuses on the design and synthesis of two novel coordination polymers (CPs), named 1 and 2, with excellent fluorescent properties. Their structures were characterized by X-ray single-crystal diffraction, revealing that both materials exhibit promising fluorescence performance, indicating their potential as fluorescent detection tools. Additionally, 1 was chosen to be combined with chitosan (CS), resulting in the successful fabrication of a biodegradable and non-toxic efficient drug carrier, termed CS-1@Cisplatin. This carrier possesses a large surface area and good solubility, enabling sustained drug release to target cells. Given that CXC motif chemokine receptor type 4 (CXCR4) is a key marker gene highly expressed in Rhabdomyosarcoma (RMS) cells and tissues, RMS was chosen as the biological model for testing. The results demonstrated that CS-1@Cisplatin effectively inhibited the invasiveness of RMS cells by significantly suppressing CXCR4 expression. Therefore, the system shows great potential for applications in RMS treatment, biometrics, and drug delivery, particularly in its unique advantage of targeting RMS by inhibiting the key marker gene CXCR4.
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  • 文章类型: Journal Article
    背景:减少宏基因组测序方法的应用有望成为靶向扩增子测序和全宏基因组测序方法之间的中间地带,但尚未被广泛采用作为技术。采用的主要障碍是缺乏用于处理这些新颖方法的特征的读取模拟软件。减少宏基因组测序(RMS)产生每个基因组的独特片段模式,对限制性内切酶的选择敏感,这些片段的非均匀大小选择可能会给分类学分配以及相对丰度估计带来新的挑战。
    结果:通过仿真软件的开发和应用,readsynth,我们将模拟宏基因组测序文库与现有RMS数据进行比较,以评估多个文库制备和测序步骤对下游分析结果的影响.基于每个位置的读取深度,与这些基准相比,readsynth实现了0.79Pearson的相关性和0.94Spearman的相关性。一种新的估计方法的应用,固定长度分类比,与平均或中位数覆盖率的估计相比,模拟人类肠道微生物群落的定量准确性得到了提高。
    结论:我们通过readsynth模拟研究了应用RMS技术分析微生物群落的可能优势和劣势。限制酶的选择和文库制备中的大小选择步骤是非平凡的决定,其偏向于下游谱分析和定量。本研究中研究的模拟说明了用减少代表性测序方法制备宏基因组文库的可能局限性。但也允许开发用于产生和处理由这一有前途的应用产生的序列数据的策略。
    BACKGROUND: The application of reduced metagenomic sequencing approaches holds promise as a middle ground between targeted amplicon sequencing and whole metagenome sequencing approaches but has not been widely adopted as a technique. A major barrier to adoption is the lack of read simulation software built to handle characteristic features of these novel approaches. Reduced metagenomic sequencing (RMS) produces unique patterns of fragmentation per genome that are sensitive to restriction enzyme choice, and the non-uniform size selection of these fragments may introduce novel challenges to taxonomic assignment as well as relative abundance estimates.
    RESULTS: Through the development and application of simulation software, readsynth, we compare simulated metagenomic sequencing libraries with existing RMS data to assess the influence of multiple library preparation and sequencing steps on downstream analytical results. Based on read depth per position, readsynth achieved 0.79 Pearson\'s correlation and 0.94 Spearman\'s correlation to these benchmarks. Application of a novel estimation approach, fixed length taxonomic ratios, improved quantification accuracy of simulated human gut microbial communities when compared to estimates of mean or median coverage.
    CONCLUSIONS: We investigate the possible strengths and weaknesses of applying the RMS technique to profiling microbial communities via simulations with readsynth. The choice of restriction enzymes and size selection steps in library prep are non-trivial decisions that bias downstream profiling and quantification. The simulations investigated in this study illustrate the possible limits of preparing metagenomic libraries with a reduced representation sequencing approach, but also allow for the development of strategies for producing and handling the sequence data produced by this promising application.
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  • 文章类型: Case Reports
    横纹肌肉瘤(RMS)是最常见的儿科实体恶性肿瘤之一。融合阴性,胚胎RMS是前列腺和膀胱病变中的主要组织学3。管理策略取决于临床阶段和风险组。尽管最优策略不断发展,该领域已经从激进的前期切除过渡到多模式治疗的器官保存策略,包括化疗,辐射,和手术。幸存者经常出现晚期并发症,包括生育能力和性功能受损,膀胱功能障碍,和继发性恶性肿瘤3-5。我们的病例描述了一名11岁的男性,他发展了辐射诱发的前列腺肉瘤。我们提出了一种新颖的外科技术,并强调了多学科护理的重要性。
    Rhabdomyosarcoma (RMS) is among the most common pediatric solid malignancies. Fusion-negative, embryonal RMS is the predominant histology among prostate and bladder lesions. Management strategies depend on the clinical stage and risk group. Although the optimal strategy continues to evolve, the field has transitioned from radical upfront resection to organ preservation strategies with multi-modal therapy, including chemotherapy, radiation, and surgery. Survivors frequently develop late complications, including impaired fertility and sexual function, bladder dysfunction, and secondary malignancies. Our case describes an 11-year-old male who developed a radiation-induced prostatic sarcoma. We present a novel surgical technique and highlight the importance of multidisciplinary care.
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  • 文章类型: Journal Article
    ANKRD11(锚蛋白重复结构域11)是一种染色质调节因子,是唯一与KBG综合征相关的基因,一种罕见的神经发育障碍.我们先前已经证明Ankrd11调节小鼠胚胎皮质神经发生。这里,我们在KBG综合征小鼠模型和两名确诊患者中显示了一种新的嗅球表型。鼠胚胎神经干细胞中Ankrd11的条件敲除会导致出生后嗅球发育异常,并且由于嗅球颗粒细胞层的减少而导致大小减小。我们进一步表明,鼻端迁移流有神经母细胞的不完全迁移,减少细胞增殖以及神经元的异常分化。这导致嗅球颗粒细胞层中的成神经细胞和神经元减少。体外,出生后脑室下区的Ankrd11缺陷神经干细胞显示迁移减少,扩散,和神经发生。最后,我们描述了两名临床和分子证实的KBG综合征患者,伴有嗅觉缺失和嗅球和沟发育不全/发育不全。我们的报告提供了证据,表明Ankrd11是嗅球发育和神经母细胞迁移的新型调节剂。此外,我们的研究强调了KBG综合征在小鼠和人类中与ANKRD11扰动相关的一种新的临床体征.
    ANKRD11 (ankyrin repeat domain 11) is a chromatin regulator and the only gene associated with KBG syndrome, a rare neurodevelopmental disorder. We have previously shown that Ankrd11 regulates murine embryonic cortical neurogenesis. Here, we show a novel olfactory bulb phenotype in a KBG syndrome mouse model and two diagnosed patients. Conditional knockout of Ankrd11 in murine embryonic neural stem cells leads to aberrant postnatal olfactory bulb development and reduced size due to reduction of the olfactory bulb granule cell layer. We further show that the rostral migratory stream has incomplete migration of neuroblasts, reduced cell proliferation as well as aberrant differentiation of neurons. This leads to reduced neuroblasts and neurons in the olfactory bulb granule cell layer. In vitro, Ankrd11-deficient neural stem cells from the postnatal subventricular zone display reduced migration, proliferation, and neurogenesis. Finally, we describe two clinically and molecularly confirmed KBG syndrome patients with anosmia and olfactory bulb and groove hypo-dysgenesis/agenesis. Our report provides evidence that Ankrd11 is a novel regulator of olfactory bulb development and neuroblast migration. Moreover, our study highlights a novel clinical sign of KBG syndrome linked to ANKRD11 perturbations in mice and humans.
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  • 文章类型: Journal Article
    血清神经丝轻链(sNFL)的评估已成为监测多发性硬化症(MS)的诊断和预后工具。然而,定期测量在日常实践中的应用尚不清楚.
    评估个体sNFL水平在确定复发性MS(RMS)患者疾病活动中的预测价值。
    在这项为期两年的前瞻性研究中,129例RMS患者接受了季度sNFL评估和年度MRI扫描。该研究分析了个人NFL水平与过去,电流,和未来的疾病活动。采用组水平Z得分作为比较指标。
    在37名参与者中,共观察到61次疾病活动。sNFL水平以不同的方式被证明是有价值的;它们证实了先前和当前的临床和/或放射学活动,并显示出未来90天活动的高阴性预测值。有趣的是,Z分数在预测准确性方面略微优于sNFL水平,表明疾病活动评估中替代方法的潜力。在我们的队列中,sNFL截止值10.8pg。/mL(灵敏度27%,特异性90%)和14.3pg。/mL(灵敏度15%,特异性95%)在90天内正确识别出26例放射学活动中的7例和4例,分别,有14%和15%的假阴性。当使用较低的截止值时,sNFL水平低于5pg/mL的个体(灵敏度为92%,25%的特异性,阴性预测值为94%)在接下来的3个月内经历放射学活动的可能性较小。
    个体sNFL水平可能会确认先前或当前的疾病活动,并预测RMS的短期未来放射学活动。这些发现强调了其定期测量是RMS管理和决策中的宝贵工具,在常规实践中提高临床评估的准确性。
    UNASSIGNED: The assessment of serum neurofilament light chain (sNFL) has emerged as a diagnostic and prognostic tool in monitoring multiple sclerosis (MS). However, the application of periodic measurement in daily practice remains unclear.
    UNASSIGNED: To evaluate the predictive value of individual sNFL levels in determining disease activity in patients with relapsing MS (RMS).
    UNASSIGNED: In this two-year prospective study, 129 RMS patients underwent quarterly sNFL assessments and annual MRI scans. The study analyzed the correlation between individual NFL levels and past, current, and future disease activity. Group-level Z-scores were employed as a comparative measure.
    UNASSIGNED: Among the 37 participants, a total of 61 episodes of disease activity were observed. sNFL levels proved valuable in distinct ways; they were confirmatory of previous and current clinical and/or radiological activity and demonstrated a high negative predictive value for future 90 days activity. Interestingly, Z-scores marginally outperformed sNFL levels in terms of predictive accuracy, indicating the potential for alternative approaches in disease activity assessment. In our cohort, sNFL cut-offs of 10.8 pg./mL (sensitivity 27%, specificity 90%) and 14.3 pg./mL (sensitivity 15%, specificity 95%) correctly identified 7 and 4 out of 26 cases of radiological activity within 90 days, respectively, with 14 and 15% false negatives. When using lower cut-off values, individuals with sNFL levels below 5 pg/mL (with a sensitivity of 92%, specificity of 25%, and negative predictive value of 94%) were less likely to experience radiological activity within the next 3 months.
    UNASSIGNED: Individual sNFL levels may potentially confirm prior or current disease activity and predict short-term future radiological activity in RMS. These findings underscore its periodic measurement as a valuable tool in RMS management and decision-making, enhancing the precision of clinical evaluation in routine practice.
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  • 文章类型: Case Reports
    目的:横纹肌肉瘤(RMS)的化疗耐药与低生存率相关,需要开发新的抗癌药物。Auranofin(AUR),一种抗风湿药,是具有抗癌特性的硫氧还蛋白还原酶(TXNRD)抑制剂。尽管患者来源的异种移植(PDX)模型对于研究癌症生物学至关重要,使用PDX模型的肉瘤报告很少,因为它们很少。本研究旨在使用PDX模型研究AUR治疗RMS的有效性,以评估其对局部进展的影响。
    方法:使用诊断为肺泡RMS的20岁女性来产生PDX模型。将RMSPDX肿瘤植入裸小鼠中,并分成非治疗(载体)和治疗(AUR)组。评估肿瘤体积和重量,进行免疫组织化学染色以评估肉瘤的局部进展。TXNRD-1表达与RMS患者生存概率之间的关系使用公开可用的表达队列进行评估。
    结果:AUR显著抑制RMS肿瘤随时间的进展。在切除时,它还显着抑制了肿瘤的大小和重量。组织学评估表明,AUR在PDX小鼠模型中诱导氧化应激,并通过诱导细胞凋亡抑制RMS的局部进展。发现高TXNRD-1表达是RMS患者总体生存的负面预后因素。
    结论:AUR诱导的TXNRD抑制可通过氧化应激-凋亡途径显著阻碍RMS的局部进展,如PDX模型所证明的。因此,靶向TXNRD抑制可能是治疗RMS的一种有前景的治疗策略.
    OBJECTIVE: Chemoresistance in rhabdomyosarcoma (RMS) is associated with poor survival, necessitating the development of novel anticancer drugs. Auranofin (AUR), an anti-rheumatic drug, is a thioredoxin reductase (TXNRD) inhibitor with anticancer properties. Although patient-derived xenograft (PDX) models are essential for studying cancer biology, reports on sarcomas using the PDX model are scarce because of their rarity. This study aimed to investigate the effectiveness of AUR treatment in RMS using a PDX model to evaluate its impact on local progression.
    METHODS: A 20-year-old woman who was diagnosed with alveolar RMS was used to generate the PDX model. RMS PDX tumors were implanted in nude mice and divided into non-treated (vehicle) and treated (AUR) groups. Tumor volume and weight were evaluated, and immunohistochemical staining was performed to evaluate local progression of the sarcoma. The relationship between the TXNRD-1 expression and survival probability of patients with RMS was evaluated using publicly available expression cohorts.
    RESULTS: AUR significantly suppressed RMS tumor progression over time. It also significantly suppressed the tumor size and weight at the time of excision. Histological evaluation showed that AUR induced oxidative stress in the PDX mouse models and inhibited the local progression of RMS by inducing apoptosis. High TXNRD-1 expression was found to be a negative prognostic factor for overall survival in patients with RMS.
    CONCLUSIONS: AUR-induced inhibition of TXNRDs can significantly impede the local progression of RMS through the oxidative stress-apoptosis pathway as demonstrated in PDX models. Thus, targeting TXNRD inhibition may be a promising therapeutic strategy for the treatment of RMS.
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  • 文章类型: Journal Article
    横纹肌肉瘤(RMS)是最常见的小儿软组织恶性肿瘤,具有高度的临床病理学和分子异质性。临床前体内模型对于提高我们对RMS肿瘤生物学的理解和开发新的治疗策略至关重要。然而,关于临床前RMS研究的学术数据的多样性可能会对科学家和临床医生提出挑战.因此,我们对当代RMS小鼠模型进行了系统的文献调查,以表征其表型并评估其翻译相关性.
    我们通过搜索PubMed和WebofScience数据库,确定了在2018年1月7日至2023年1月7日之间发表的论文。
    在筛选的713条记录中,118项研究(26.9%)被纳入定性综合。细胞系来源的异种移植物(CDX)是最常用的(n=75,63.6%),其次是患者来源的异种移植物(PDX)和同基因模型,各占11.9%(n=14),和基因工程小鼠模型(GEMM)(n=7,5.9%)。在5.9%(n=7)的研究中报告了不同模型类别的组合。一项研究采用了病毒诱导的RMS模型。总的来说,40.0%(n=30)的研究利用CDX模型建立肺泡RMS(aRMS),而38.7%(n=29)为胚胎表型(eRMS)。有20.0%(n=15)的研究涉及aRMS和eRMS亚型的组合。在一项研究中(1.3%),RMS表型为梭形细胞/硬化。皮下异种移植物(n=66,55.9%)的使用频率高于原位模型(n=29,24.6%)。值得注意的是,所使用的细胞系均不来源于未经治疗的原发性肿瘤。只有少数研究调查了传播的RMS表型(n=16,13.6%)。RMS模型的利用领域包括测试药物(n=64,54.2%),研究肿瘤发生(n=56,47.5%),肿瘤建模(n=19,16.1%),成像(n=9,7.6%),放射治疗(n=6,5.1%),与放疗相关的长期影响(n=3,2.5%),并调查生物标志物(n=1,0.8%)。值得注意的是,没有集中于手术的临床前研究。
    这一最新综述强调了对具有来自原发性未治疗肿瘤的播散表型和细胞系的小鼠模型的需求。此外,应努力针对未充分开发的领域,如手术,放射治疗,和生物标志物。
    UNASSIGNED: Rhabdomyosarcoma (RMS) is the most common pediatric soft-tissue malignancy, characterized by high clinicalopathological and molecular heterogeneity. Preclinical in vivo models are essential for advancing our understanding of RMS oncobiology and developing novel treatment strategies. However, the diversity of scholarly data on preclinical RMS studies may challenge scientists and clinicians. Hence, we performed a systematic literature survey of contemporary RMS mouse models to characterize their phenotypes and assess their translational relevance.
    UNASSIGNED: We identified papers published between 01/07/2018 and 01/07/2023 by searching PubMed and Web of Science databases.
    UNASSIGNED: Out of 713 records screened, 118 studies (26.9%) were included in the qualitative synthesis. Cell line-derived xenografts (CDX) were the most commonly utilized (n = 75, 63.6%), followed by patient-derived xenografts (PDX) and syngeneic models, each accounting for 11.9% (n = 14), and genetically engineered mouse models (GEMM) (n = 7, 5.9%). Combinations of different model categories were reported in 5.9% (n = 7) of studies. One study employed a virus-induced RMS model. Overall, 40.0% (n = 30) of the studies utilizing CDX models established alveolar RMS (aRMS), while 38.7% (n = 29) were embryonal phenotypes (eRMS). There were 20.0% (n = 15) of studies that involved a combination of both aRMS and eRMS subtypes. In one study (1.3%), the RMS phenotype was spindle cell/sclerosing. Subcutaneous xenografts (n = 66, 55.9%) were more frequently used compared to orthotopic models (n = 29, 24.6%). Notably, none of the employed cell lines were derived from primary untreated tumors. Only a minority of studies investigated disseminated RMS phenotypes (n = 16, 13.6%). The utilization areas of RMS models included testing drugs (n = 64, 54.2%), studying tumorigenesis (n = 56, 47.5%), tumor modeling (n = 19, 16.1%), imaging (n = 9, 7.6%), radiotherapy (n = 6, 5.1%), long-term effects related to radiotherapy (n = 3, 2.5%), and investigating biomarkers (n = 1, 0.8%). Notably, no preclinical studies focused on surgery.
    UNASSIGNED: This up-to-date review highlights the need for mouse models with dissemination phenotypes and cell lines from primary untreated tumors. Furthermore, efforts should be directed towards underexplored areas such as surgery, radiotherapy, and biomarkers.
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  • 文章类型: Case Reports
    横纹肌肉瘤(RMS)是儿童最常见的软组织肉瘤。本研究报告了一名2岁女性的病例,该女性表现出腹痛和明显的腹部肿块。放射学检查未能揭示肿块的组织起源,切开的活检证实了胚胎RMS的诊断。新辅助化疗后进行手术切除。观察到肿块的骨盆端与左脐内侧韧带延续。病人的术后过程是顺利的,随访影像学显示无复发证据.本病例报告是第一例左脐内侧韧带起源RMS的非综合征病例。
    Rhabdomyosarcoma (RMS) is the most common soft-tissue sarcoma in children. The present study reports the case of a 2-year-old female who presented with abdominal pain and a palpable abdominal mass. Radiological investigations failed to reveal the tissue origin of the mass and a tru-cut biopsy confirmed the diagnosis of embryonal RMS. Surgical excision was performed after neo-adjuvant chemotherapy. The pelvic end of the mass was observed to continue with the left medial umbilical ligament. The patient\'s postoperative course was uneventful, and follow-up imaging showed no evidence of recurrence. Τhe present case report is the first non-syndromic case with left umbilical medial ligament-originated RMS.
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  • 文章类型: Journal Article
    目的:当运动超过乳酸阈值(LT)时,氧气吸收的缓慢成分([公式:见文字])出现,主要归因于II型纤维的逐渐募集。然而,收缩经济的逐渐衰退也可能导致这种情况。我们研究了等距收缩夹紧扭矩(T)或肌肉激活过程中的摄氧量([公式:参见正文]),以量化这两种机制的贡献。
    方法:我们评估了腿伸肌的7分钟T,在周期性等距收缩(收缩/松弛5s/5s)期间,11名志愿者(21±2yy;1.73±0.11m;67±14kg)来自股外侧肌(VL)的净摄氧量([公式:参见正文])和均方根(RMS):(i)在自愿收缩(MVC)的65%(最大扭矩);(ii)保持等于(FB-EMG的65%)的水平。
    结果:[公式:见正文]第3分钟后FB-扭矩随时间增加([公式:见正文]=94×t+564;R2=0.99;P=0.001),但不是在FB-EMG期间。[公式:见正文]/T仅在FB-扭矩期间增加([公式:见正文]/T=1.10×t+0.57;R2=0.99;P=0.001)。FB-Torque的RMS大于FB-EMG,并且在运动的前三分钟显着增加,直到试验结束。这表明,尽管[公式:见正文],但被招募的货币单位池保持不变。
    结论:RMS的分析,[公式:见文本]和FB-扭矩期间的T表明,可归因于收缩效率衰减的内在机制导致[公式:见文本]的增加等于总数[公式:见文本]的18%。
    OBJECTIVE: When exercising above the lactic threshold (LT), the slow component of oxygen uptake ([Formula: see text]) appears, mainly ascribed to the progressive recruitment of Type II fibers. However, also the progressive decay of the economy of contraction may contribute to it. We investigated oxygen uptake ([Formula: see text]) during isometric contractions clamping torque (T) or muscular activation to quantify the contributions of the two mechanisms.
    METHODS: We assessed for 7 min T of the leg extensors, net oxygen uptake ([Formula: see text]) and root mean square (RMS) from vastus lateralis (VL) in 11 volunteers (21 ± 2 yy; 1.73 ± 0.11 m; 67 ± 14 kg) during cyclic isometric contractions (contraction/relaxation 5 s/5 s): (i) at 65% of maximal voluntary contraction (MVC) (FB-Torque) and; (ii) keeping the level of RMS equal to that at 65% of MVC (FB-EMG).
    RESULTS: [Formula: see text] after the third minute in FB-Torque increased with time ([Formula: see text] = 94 × t + 564; R2 = 0.99; P = 0.001), but not during FB-EMG. [Formula: see text]/T increased only during FB-Torque ([Formula: see text]/T = 1.10 × t + 0.57; R2 = 0.99; P = 0.001). RMS was larger in FB-Torque than in FB-EMG and significantly increased in the first three minutes of exercise to stabilize till the end of the trial, indicating that the pool of recruited MUs remained constant despite [Formula: see text].
    CONCLUSIONS: The analysis of the RMS, [Formula: see text] and T during FB-Torque suggests that the intrinsic mechanism attributable to the decay of contraction efficiency was responsible for an increase of [Formula: see text] equal to 18% of the total [Formula: see text].
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