VCD

VCD
  • 文章类型: Journal Article
    运动诱发的喉阻塞(EILO)是年轻人劳力性呼吸问题的常见原因,5%-7%的年轻人。它是由喉结构的矛盾吸气内收引起的,并通过高强度运动期间喉的连续可视化来诊断。经验数据表明,EILO由不同的亚型组成,需要不同的治疗方法。目前应用的治疗方法并不依赖于随机对照试验(RCTs),因此,无法建立基于证据的指南。该协议描述了在称为HelpILO的大型前瞻性RCT中应用于EILO患者的言语治疗方法。
    在Haukeland大学医院连续诊断为EILO的同意患者被随机分为四个治疗组。言语治疗代表了其中两个,以基于一般言语治疗原理和腹式呼吸的结构化方式提供,结合过去几十年来在我们医院获得的这些患者的经验。HelpILO的主要结果测量是喉镜下可视化喉内收的变化,在高峰运动前与干预后,使用经过验证的评分系统。
    尽管在EILO患者中广泛使用言语治疗,这种方法在随机对照试验中没有得到充分的检验,因此,这项研究在道德上被认为是合适的。该研究将提供主要呼吸和喉科协会最近发表的声明中列为优先事项的知识,并应从事该领域的临床医生和研究人员的要求。结果将在相关会议上公布,病人论坛,和媒体平台,并在相关同行评审的国际期刊上发表。
    UNASSIGNED: Exercise induced laryngeal obstruction (EILO) is a common cause of exertional breathing problems in young individuals, relevant to 5%-7% of young people. It is caused by paradoxical inspiratory adduction of laryngeal structures and diagnosed by continuous visualization of the larynx during high intensity exercise. Empirical data suggest that EILO consists of different subtypes that require different therapeutic approaches. Currently applied treatment approaches do not rest on randomized controlled trials (RCTs), and thus evidence-based guidelines cannot be established. This protocol describes the speech therapy treatment approach which is applied to EILO patients in a large prospective RCT called HelpILO.
    UNASSIGNED: Consenting patients consecutively diagnosed with EILO at Haukeland University Hospital are randomized into four treatment arms. Speech therapy is represented in two of these, provided in a structured manner based on general speech therapy principles and abdominal breathing, combined with experience obtained with these patients at our hospital during the last decades. The main outcome measure of HelpILO is changes of laryngoscopically visualized laryngeal adduction, rated at peak exercise before vs. after interventions, using a validated scoring system.
    UNASSIGNED: Despite widespread use of speech therapy in patients with EILO, this approach is insufficiently tested in RCTs, and the study is therefore considered ethically appropriate. The study will provide knowledge listed as a priority in a recent statement issued by major respiratory and laryngological societies and requested by clinicians and researchers engaged in this area. The results will be presented at relevant conferences, patient fora, and media platforms, and published in relevant peer reviewed international journals.
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  • 文章类型: Journal Article
    (R)-(-)-Mellein,(3R,4R)-4-羟基mellein和(3R,4S)-4-羟基mellein从真菌中获得,也就是来自双创,被研究为一类呈现ESIPT(激发态分子内质子转移)现象的天然产物,通过荧光和CPL(圆偏振发光)。在研究之前,除了NMR光谱外,还通过ECD和VCD(电子和振动圆二色性)光谱法评估了绝对构型。发现ESIPT在这些系统中发生得非常快,并且没有观察到双重荧光。实验研究得到了ECD和CPL光谱的TD-DFT计算的支持,加上MD动力学,以跟踪激发态下的质子转移,并仔细分析内酯环的起皱动力学。还通过相同的手性实验和理论方法研究了三种化合物的去质子化形式,显示了如何在天然化合物中不仅可以找到生物活性,还可以找到生物相容性传感探针。
    (R)-(-)-Mellein, (3R,4R)-4-hydroxymellein and (3R,4S)-4-hydroxymellein obtained from fungi, i. e. from Diplodia globulosa, were investigated as a class of natural products presenting ESIPT (excited state intramolecular proton transfer) phenomenon, through fluorescence and CPL (circularly polarized luminescence). The study was preceded by the assessment of the absolute configuration through ECD and VCD (electronic and vibrational circular dichroism) spectroscopies in addition to NMR spectra. It is found that ESIPT takes place in these systems very rapidly, and no dual fluorescence has been observed. The experimental study is backed up by TD-DFT calculations of ECD and CPL spectra, plus MD calculations to follow proton transfer in the excited state and careful analysis of the puckering dynamics of the lactone ring. Deprotonated forms of the three compounds were also investigated by the same chiroptical experimental and theoretical methods, showing how one can find in natural compounds not only biological activity but also biologically compatible sensing probes.
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  • 文章类型: Journal Article
    背景:静脉血管通路的并发症通常是非致命性的,但却是经静脉导管介入治疗后最常见的并发症。血管闭合装置(VCD)最近已变得可用于静脉闭合。
    目的:本研究旨在评估在接受导管消融的患者中使用缝线介导的VCD进行实时超声引导静脉闭合的可行性和有效性。
    方法:这项单中心观察性研究纳入了226例接受选择性导管消融术和股静脉穿刺的连续患者。关于止血,2022年后(n=123)在实时超声引导下使用VCD封堵血管,2021年无超声引导(n=103).静脉通路部位相关并发症的发生(主要,未成年人,或其他)进行了比较。
    结果:使用超声引导的患者的设备故障率明显低于没有超声引导的患者(1.6%vs.6.3%;p=0.048)。所有静脉通路部位相关并发症的发生率在有超声引导的患者中显著低于无超声引导的患者(4.9%vs.18.4%,p=0.001)。超声引导患者的步行时间比没有超声引导的患者短(2.0±0.1小时与2.2±0.6小时,p<0.001)。
    结论:实时超声引导可以减少设备故障,通路部位相关并发症,以及使用VCD进行静脉闭合时的下床时间。
    BACKGROUND: Venous vascular access complications are usually nonfatal but are the most common complications after transvenous catheter intervention. Vascular closure devices (VCDs) have recently become available for venous closure.
    OBJECTIVE: This study aimed to evaluate the feasibility and efficacy of real-time ultrasound-guided venous closure with suture-mediated VCDs in patients who underwent catheter ablation.
    METHODS: This single-center observational study enrolled 226 consecutive patients who underwent elective catheter ablation with femoral venipuncture. For hemostasis, vessel closure by VCD was performed with real-time ultrasound guidance after 2022 (n = 123) and without ultrasound guidance in 2021 (n = 103). The occurrence of venous access site-related complications (major, minor, or other) was compared.
    RESULTS: The rate of device failure was significantly lower in patients with ultrasound guidance than in those without (1.6% vs 6.3%; P = .048). The occurrence of all venous access site-related complications was significantly lower in patients with ultrasound guidance than in those without (4.9% vs 18.4%; P = .001). Time to ambulation was shorter in patients with ultrasound guidance than in those without (2.0 ± 0.1 hours vs 2.2 ± 0.6 hours; P < .001).
    CONCLUSIONS: Real-time ultrasound guidance can reduce device failure, access site-related complications, and time to ambulation in performing venous closure with a VCD.
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  • 文章类型: Journal Article
    卵巢激素释放的突然停止与肌肉收缩功能的下降有关,然而,逐渐的卵巢衰竭对整个周期的肌肉收缩性的影响,早期和晚期更年期仍不清楚。在这项研究中,使用4-乙烯基环己烯二环氧化物(VCD)诱导的卵巢衰竭小鼠模型来检查肌肉机械功能的时程变化。在40(围绝经期早期)评估雌性小鼠的足底屈肌(VCD:n=10;CON:n=8),80(围绝经期晚期),初次VCD注射后120天(更年期发作)和176天(更年期晚期)。在频率范围(10-200Hz)上建立转矩-频率关系。针对相对载荷(最大等距扭矩为10-80%)引起等渗动态收缩,以确定扭矩-速度-功率关系。然后,小鼠使用间歇性100Hz等距收缩进行疲劳任务,直到扭矩下降60%。抽搐的恢复,在任务失败后10分钟跟踪10Hz和100Hz扭矩。此外,来自指短屈肌的完整肌纤维经历了疲劳任务(在70Hz下重复50次),然后监测10和100Hz的Tetanic[Ca2]10分钟。VCD小鼠在所有时间点均表现出比对照低16%的抽搐扭矩。除了抽搐扭矩,10Hz扭矩和10Hz破伤风[Ca2+],在恢复过程中,VCD相对于疲劳前显示出更大的值,在恢复过程中,对照组和VCD小鼠之间没有观察到显着差异。这些结果表明,逐渐的卵巢衰竭对体内肌肉机械功能的损害很小,在疲劳恢复期间,主要观察到低频刺激的微小变化。
    The abrupt cessation of ovarian hormone release is associated with declines in muscle contractile function, yet the impact of gradual ovarian failure on muscle contractility across peri-, early- and late-stage menopause remains unclear. In this study, a 4-vinylcyclohexene diepoxide (VCD)-induced ovarian failure mouse model was used to examine time course changes in muscle mechanical function. Plantar flexors of female mice (VCD: n = 10; CON: n = 8) were assessed at 40 (early perimenopause), 80 (late perimenopause), 120 (menopause onset) and 176 (late menopause) days post-initial VCD injection. A torque-frequency relationship was established across a range of frequencies (10-200 Hz). Isotonic dynamic contractions were elicited against relative loads (10-80% maximal isometric torque) to determine the torque-velocity-power relationship. Mice then performed a fatigue task using intermittent 100 Hz isometric contractions until torque dropped by 60%. Recovery of twitch, 10 Hz and 100 Hz torque were tracked for 10 min post-task failure. Additionally, intact muscle fibres from the flexor digitorum brevis underwent a fatigue task (50 repetitions at 70 Hz), and 10 and 100 Hz tetanic [Ca2+] were monitored for 10 min afterward. VCD mice exhibited 16% lower twitch torque than controls across all time points. Apart from twitch torque, 10 Hz torque and 10 Hz tetanic [Ca2+], where VCD showed greater values relative to pre-fatigue during recovery, no significant differences were observed between control and VCD mice during recovery. These results indicate that gradual ovarian failure has minimal detriments to in vivo muscle mechanical function, with minor alterations observed primarily for low-frequency stimulation during recovery from fatigue.
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  • 文章类型: Journal Article
    卵巢储备的下降导致更年期和血清雌激素减少。微小RNA是小的非编码RNA,它可以调节基因表达,由细胞分泌并通过外泌体运输到血清中。血清miRNAs调节组织功能和疾病发展。因此,本研究的目的是鉴定用17β-雌二醇(E2)诱导的绝经小鼠血清外泌体中的miRNA谱.将雌性小鼠分为三组,包括对照组(CTL),注入4-乙烯基环己烯二环氧化物(VCD),用VCD加E2(VCD+E2)注入。无周期性和卵巢卵泡数量显著减少证实了Estropause(p<0.05)。与CTL女性相比,VCD和VCDE2在更年期的体重增长更高(p=0.02)。从血清中提取的外来体进行miRNA测序,并检测到402个miRNA。8个miRNAs在CTL和VCD组之间差异调节,在CTL和VCD+E2组之间调节的七个miRNA,和10个在VCD和VCD+E2组之间调节的miRNA。在两个VCD组中,只有miR-200a-3p和miR-200b-3p在血清外泌体和卵巢组织中均上调,表明这些外泌体miRNA可能与卵巢活动有关。在肝组织中,只有miR-370-3p(p=0.02)在VCD+E2组中上调,如在血清中观察到的。我们的结果表明,VCD诱导的更年期和E2替代对血清外泌体miRNAs的谱有影响。miR-200家族在血清外泌体和卵巢组织中增加,可能是卵巢功能的候选生物标志物。
    The decline in the ovarian reserve leads to menopause and reduced serum estrogens. MicroRNAs are small non-coding RNAs, which can regulate gene expression and be secreted by cells and trafficked in serum via exosomes. Serum miRNAs regulate tissue function and disease development. Therefore, the aim of this study was to identify miRNA profiles in serum exosomes of mice induced to estropause and treated with 17β-estradiol (E2). Female mice were divided into three groups including control (CTL), injected with 4-Vinylcyclohexene diepoxide (VCD), and injected with VCD plus E2 (VCD + E2). Estropause was confirmed by acyclicity and a significant reduction in the number of ovarian follicles (p < 0.05). Body mass gain during estropause was higher in VCD and VCD + E2 compared to CTL females (p = 0.02). Sequencing of miRNAs was performed from exosomes extracted from serum, and 402 miRNAs were detected. Eight miRNAs were differentially regulated between CTL and VCD groups, seven miRNAs regulated between CTL and VCD + E2 groups, and ten miRNAs regulated between VCD and VCD + E2 groups. Only miR-200a-3p and miR-200b-3p were up-regulated in both serum exosomes and ovarian tissue in both VCD groups, suggesting that these exosomal miRNAs could be associated with ovarian activity. In the hepatic tissue, only miR-370-3p (p = 0.02) was up-regulated in the VCD + E2 group, as observed in serum. Our results suggest that VCD-induced estropause and E2 replacement have an impact on the profile of serum exosomal miRNAs. The miR-200 family was increased in serum exosomes and ovarian tissue and may be a candidate biomarker of ovarian function.
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  • 文章类型: Journal Article
    L-DOPA作为多巴胺的前体发挥着关键作用,是帕金森病的标准治疗方法。最近的研究强调了具有较长生物半衰期的氘代1-DOPA类似物的潜在治疗优势。对于它们的光谱特性,l-DOPA本身的详细表征是必要的。本文对l-DOPA的振动光谱进行了彻底的检查,特别强调手性敏感的VOA技术。我们成功获得了阳离子形式的l-DOPA的高质量拉曼和ROA光谱,在低pH条件下,和100毫克/毫升的高浓度。这些光谱覆盖了很宽的光谱范围,允许与理论模拟进行精确比较。我们还获得了IR和VCD光谱,但是由于狭窄的可接近光谱区域,它们面临着局限性。对l-DOPA构象景观的探索揭示了其内在的灵活性,具有多个共存的构象。为了表征这些构象,我们采用了两种方法:一种涉及势能表面扫描与隐式溶剂化,另一个利用分子动力学模拟与明确的溶剂化。比较来自不同构象异构体组的ROA光谱并应用光谱分解对于确定正确的构象异构体比率至关重要。显式溶剂化的使用显着改善了最终模拟光谱轮廓的质量。构象比的准确测定,而不是仅仅依靠平均光谱的数量,对仿真精度起着至关重要的作用。总之,我们的研究为l-DOPA的结构和构象行为提供了有价值的见解,并为其氘代类似物的后续光谱研究提供了宝贵的资源。
    l-DOPA plays a critical role as a precursor to dopamine and is a standard treatment for Parkinson\'s disease. Recent research has highlighted the potential therapeutic advantages of deuterated l-DOPA analogs having a longer biological half-life. For their spectroscopic characterization, the in-detail characterization of l-DOPA itself is necessary. This article presents a thorough examination of the vibrational spectra of l-DOPA, with a particular emphasis on chirally sensitive VOA techniques. We successfully obtained high-quality Raman and ROA spectra of l-DOPA in its cationic form, under low pH conditions, and at a high concentration of 100 mg/ml. These spectra cover a broad spectral range, allowing for precise comparisons with theoretical simulations. We also obtained IR and VCD spectra, but they faced limitations due to the narrow accessible spectral region. Exploration of l-DOPA\'s conformational landscape revealed its intrinsic flexibility, with multiple coexisting conformations. To characterize these conformations, we employed two methods: one involved potential energy surface scans with implicit solvation, and the other utilized molecular dynamics simulations with explicit solvation. Comparing ROA spectra from different conformer groups and applying spectral decomposition proved crucial in determining the correct conformer ratios. The use of explicit solvation significantly improved the quality of the final simulated spectral profiles. The accurate determination of conformer ratios, rather than solely relying on the number of averaged spectra, played a crucial role in simulation accuracy. In conclusion, our study offers valuable insights into the structure and conformational behavior of l-DOPA and represents a valuable resource for subsequent spectroscopic studies of its deuterated analogs.
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  • 文章类型: Journal Article
    目的:程序性细胞死亡4(PDCD4)在卵巢早衰(POI)中起什么作用?
    方法:构建PDCD4基因敲除(PDCD4-/-)小鼠模型,用4-乙烯基环己烯二氧化(VCD)建立了类似于人类POI的POI小鼠模型,设计了过表达PDCD4的腺病毒,并研究了其在体内外POI中的调节作用。
    结果:PDCD4在POI患者(P≤0.002蛋白和mRNA)和VCD诱导POI小鼠的卵巢颗粒细胞中表达显著增加(小鼠卵巢和颗粒细胞中蛋白表达均P<0.001)。在POI诱导的小鼠模型中,PDCD4敲除显著增加抗苗勒管激素,雌二醇和发育中的卵泡数量,PI3K-AKT-Bcl2/Bax信号通路参与其中。
    结论:小鼠模型中PDCD4的表达和调节显著影响POI病理。这种效应与Bcl2/Bax的调节和PI3K-AKT信号通路的激活密切相关。
    OBJECTIVE: What role does programmed cell death 4 (PDCD4) play in premature ovarian insufficiency (POI)?
    METHODS: A PDCD4 gene knockout (PDCD4-/-) mouse model was constructed, a POI mouse model was established similar to human POI with 4-vinylcyclohexene dioxide (VCD), a PDCD4-overexpressed adenovirus was designed and the regulatory role in POI in vitro and in vivo was investigated.
    RESULTS: PDCD4 expression was significantly increased in the ovarian granulosa cells of patients with POI (P ≤ 0.002 protein and mRNA) and mice with VCD-induced POI (P < 0.001 protein expression in both mouse ovaries and granulosa cells). In POI-induced mice model, PDCD4 knockouts significantly increased anti-Müllerian hormone, oestrodiol and numbers of developing follicles, and the PI3K-AKT-Bcl2/Bax signalling pathway is involved in it.
    CONCLUSIONS: The expression and regulation of PDCD4 significantly affects the POI pathology in a mouse model. This effect is closely related to the regulation of Bcl2/Bax and the activation of the PI3K-AKT signalling pathway.
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  • 文章类型: Journal Article
    在不同的条件下,DNA双螺旋可以采取不同的几何形式。在它的大量构象中,除了“规范”B表格之外,A,C,Z形式是众所周知的,还有D,Hoogsteen,和X形式是鲜为人知的。DNA在当地取A,C,Z在细胞中形成,与蛋白质的复合物。我们比较了检测非规范DNA构象的不同方法:X射线,IR,和拉曼光谱,红外和紫外区域的线性和圆二色性,以及NMR(化学位移及其各向异性的测量,标量和残余偶极耦合以及来自NOESY(核Overhauser效应光谱)数据的质子间距离)。我们讨论了应用这些方法的困难,实验结果的理论解释问题,以及可靠鉴定非规范DNA构象的前景。
    Under different conditions, the DNA double helix can take different geometric forms. Of the large number of its conformations, in addition to the \"canonical\" B form, the A, C, and Z forms are widely known, and the D, Hoogsteen, and X forms are less known. DNA locally takes the A, C, and Z forms in the cell, in complexes with proteins. We compare different methods for detecting non-canonical DNA conformations: X-ray, IR, and Raman spectroscopy, linear and circular dichroism in both the infrared and ultraviolet regions, as well as NMR (measurement of chemical shifts and their anisotropy, scalar and residual dipolar couplings and inter-proton distances from NOESY (nuclear Overhauser effect spectroscopy) data). We discuss the difficulties in applying these methods, the problems of theoretical interpretation of the experimental results, and the prospects for reliable identification of non-canonical DNA conformations.
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  • 文章类型: Journal Article
    自然界产生结构复杂分子的能力使得确定天然产物的绝对构型成为一项具有挑战性的任务。尽管广泛的NMR分析通常可以可靠地分配相对配置,绝对立体化学的分配通常通过对相关分子获得的旋光度(OR)和/或电子圆二色性(ECD)数据的经验比较来进行。这样的方法,然而,可能导致错误分配和随之而来的错误传播。在这里,我们介绍了名为(+)-nectamazinA的双环(3.2.1)辛烷新木素的情况。该化合物于2009年首次从NectandraamazonumNees报道。(月桂科),其绝对构型确定为7R,8S,3\'S,4\'R,5\'S通过实验ECD光谱学。我们对竹叶(Lauraceae)的化学研究导致了()-nectamazinA的分离。对OR的广泛分析,ECD,和由量子化学计算辅助的振动CD数据,然而,表示(+)-nectamazinA有7S,8R,3\'R,4\'S,5\'R绝对配置,与文献中报道的配置相冲突。()-nectamazinA的原始错误分配的原因来自对具有不同发色系统的结构相关分子获得的实验OR和ECD数据的直接比较。作为替代,VCD光谱法被认为是对双环(3.2.1)辛烷新木脂素的立体化学研究更可靠和灵敏的技术。
    The ability of nature to produce structurally complex molecules makes the determination of the absolute configuration of natural products a challenging task. Although extensive NMR analysis generally allows for the reliable assignment of relative configurations, the assignments of absolute stereochemistry are commonly performed by empirical comparisons of optical rotation (OR) and/or electronic circular dichroism (ECD) data obtained for related molecules. Such an approach, however, may lead to misassignments and consequent error propagations. Herein, we present the case of the bicyclo(3.2.1)octane neolignan named (+)-nectamazin A. This compound was first reported in 2009 from Nectandra amazonum Nees. (Lauraceae) and had its absolute configuration determined as 7R,8S,3\'S,4\'R,5\'S by means of experimental ECD spectroscopy. Our chemical studies on Ocotea aciphylla (Lauraceae) led to the isolation of (+)-nectamazin A. The extensive analysis of OR, ECD, and vibrational CD data aided by quantum chemical calculations, however, indicated (+)-nectamazin A to have the 7S,8R,3\'R,4\'S,5\'R absolute configuration, in conflict with the configuration reported in the literature. The cause of the original incorrect assignment of (+)-nectamazin A derives from the direct comparison of experimental OR and ECD data obtained for structurally related molecules with different chromophoric systems. As an alternative, VCD spectroscopy is presented as a more reliable and sensitive technique to stereochemical investigations of bicyclo(3.2.1)octane neolignans.
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