Electromyographic activity of trunk and hip muscles during stabilization exercises in four-point kneeling in healthy volunteers

Stabilization exercises are intended to optimize function of the muscles that are believed to govern trunk stability. Debate exists whether certain muscles are more important than others in optimally performing these exercises. Thirty healthy volunteers were asked to perform three frequently prescribed stabilization exercises in four-point kneeling. The electromyographic activity of different trunk and hip muscles was evaluated. Average amplitudes obtained during the exercises were normalized to the amplitude in maximal voluntary contraction (% MVIC). During all three exercises, the highest relative muscle activity levels (> 20% MVIC) were consistently found in the ipsilateral lumbar multifidus and gluteus maximus. During both the single leg extension (exercise 1) and the leg and arm extension exercise (exercise 2) the contralateral internal oblique and ipsilateral external oblique reached high levels (> 20%MVIC). During exercise 2 there were also high relative activity levels of the ipsilateral lumbar part and the contralateral thoracic part of the iliocostalis lumborum and the contralateral lumbar multifidus. During the leg and arm extension exercise with contralateral hip flexion (exercise 3) there were high relative muscle activity levels of all back muscles, except for the latissimus dorsi muscle. The lowest relative muscle activity levels (< 10% MVIC) were found in the rectus abdominis and the ipsilateral internal oblique during all exercises, and in the contralateral gluteus maximus during exercises 1 and 2. The results of this study show that in exercises in four-point kneeling performed by healthy subjects, hip and trunk muscles seem to work together in a harmonious way. This shows that when relative activity of muscles is measured, both “global and local” muscles function together in order to stabilize the spine.     

Diagnosis and treatment of expanding haematoma of the lateral abdominal wall after blunt abdominal trauma

We report a rare case of an expanding post-traumatic lateral abdominal wall haematoma. A superselective arteriogram of the deep circumflex iliac artery showed extravasation from the ascending branch, urging emergency therapy. Microcoil and Gelfoam embolisation was successfully performed. Haematomas of the abdominal wall can be divided in the common rectus sheath haematomas and the rare haematomas of the lateral abdominal wall. Differentiating both entities is essential, since there is a strong difference in their vascular supply. The typical vascular supply of the lateral abdominal wall is discussed, with emphasis on the ascending branch of the deep circumflex iliac artery. Received: 13 November 1998; Revision received: 8 February 1999; Accepted: 3 March 1999     

Expression and subcellular localization of dystrophin in skeletal, cardiac and smooth muscles during the human development

Dystrophin, the product of the DMD gene, is present in all muscle types in normal individuals. Its function has yet to be elucidated, but its absence or the presence of a truncated version of the protein is responsible for the appearance of Duchenne and Becker muscular dystrophies. Using monoclonal antibodies raised against distinct regions of the dystrophin protein, we have examined its expression and subcellular distribution during the human development in skeletal and smooth muscles. We show that both dystrophin expression and its association to the plasma membrane take place earlier in cardiac and smooth muscles (8 weeks of gestation) than in skeletal muscle. In skeletal muscle, dystrophin is first detected in the cytoplasm, and progressively localizes to the plasma membrane from 10 weeks onwards. Since we have obtained marked differences in staining when using antibodies against either a central region of the protein or the C-terminal part, we suggest that different fetal and adult dystrophin isoforms are expressed, probably differing in their C-terminal domain. These findings are discussed in the context of the pathology of Duchenne muscular dystrophy.     

粉防己碱对小鼠、家兔和豚鼠肠平滑肌的作用

目的　研究钙拮抗剂粉防己碱 (tetrandrine,Tet)对小鼠、家兔和豚鼠肠平滑肌的影响。方法　用小鼠胃肠推进运动法 ,家兔和豚鼠离体肠平滑肌标本。结果　 Tet(1 0～ 1 5 mg· kg-1,ig)对小鼠肠平滑肌运动无明显影响 ,Tet抑制家兔离体回肠自发性收缩 ,Tet(1 0 μmol·L-1)抑制氨甲酰胆碱诱导的豚鼠结肠带依内钙收缩 ,但不影响依外钙收缩。Tet浓度依赖性地使 KCl引起的豚鼠离体结肠带收缩量效曲线非平行右移 ,最大反应降低 ,p D2 为 4.0 1。结论　 Tet主要抑制肠平滑肌电压依赖性钙通道 (PDC) ,阻止 Ca2 + 通过 PDC,但对胃肠运动功能影响较小     

眼外肌的初步研究

解剖了４６个固定成人尸体眼眶。测量了各眼外肌的肌腹长，接触弧长和最大横断面积等。外直肌分别为３７．４１和１２．３４ｍｍ及３６．２１ｍｍ＾２，内直肌分别为３６．１１和８．４８ｍｍ及３４．４６ｍｍ＾２，上直肌分别为３８．７５和１１．００ｍｍ及２４．８１ｍｍ＾２，下直肌分别为３６．４０和７．９１ｍｍ及２９．９３ｍｍ＾２，上斜肌分别为３０．８３和９．８４ｍｍ及１５．１７ｍｍ＾２，下斜肌分别为３１．０９和１     

普罗帕酮和心肌快钠通道结合及解离过程的动力学

<正> 普罗帕酮(propafenone,Pro)又称心律平,是I_c类抗心律失常药。我室对国产Pro的研究表明,它对心肌快钠通道和慢钙通道都有阻滞作用。作为I类抗心律失常药物,其抗心律失常和致心律失常作用强度和其与心肌快钠通道结合,解离速率有关。本文对国产Pro进行动力学研究,并与国外报道进行比较,为临床用药提供参考。     

Pathogenesis of respiratory failure in neuromuscular diseases: Diagnosis and treatment

In reviewing the pathogenesis of respiratory failure in neuromuscular diseases, with special reference to the ventilatory pump, we propose specific tests of the respiratory muscle pump alongside the standard function tests for assessing the respiratory system. Accurate diagnosis must be followed by target therapy, which must be given as often and for as long as needed. Early evaluation and treatment of the respiratory problems are essential to prognosis, whether of survival or of quality of life, in neuromuscular diseases.

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Sommario Gli Autori esaminano la patogenesi dell'insufficienza respiratoria nelle malattie neuromuscolari con particolare riferimento ai problemi della pompa ventilatoria. Vengono proposti, per la valutazione del sistema respiratorio, tests specific per la pompa muscolare respiratoria accanto alle metodiche classiche di esame funzionale. Dal punto di vista terapeutico viene sottolineata l'importanza di interventi mirati, dopo una diagnosi accurata, realizzati per tempi e con frequenza adeguati per poter essere significativi. Viene infine marcata l'importanza della valutazione precoce e del trattamento dei problemi respiratori nella prognosi quoad vitam e quoad valetudinem delle malattie neuromuscolari.

     

八厘麻毒素对豚鼠心乳头肌膜电位及收缩力的影响

用固定频率起搏的离体豚鼠心乳头肌标本,研究了RTX对心肌膜电位及收缩力的影响。结果表明:RTX增加心肌Fc,降低RP和APA,缩短APD₂₀和APD₅₀,其降低RP的作用与其增加Fc的作用相平行。RTX的全部效应均是时间和浓度依赖性的。在给RTx前和后加用TTX能分别减弱和逆转RTX的作用,并能迅速抵消RTX所诱发的自动节律活动。本实验结果提示:RTX能选择性地作用于心肌快Na⁺通道,与TTX有拮抗作用,似可作为研究心肌离子转运的工具药之一。     

Effect of tumor necrosis factor on cerebral arterial tone

Department of Normal Physiology, Sverdlovsk Medical Institute. Laboratory of, Metabolic Provision for Brain Functions, I. S. Beritashvili Institute of Physiology, Academy of Sciences of the Georgian SSR, Tbilisi. (Presented by Academician of the Academy of Medical Sciences of the USSR A. S. Barybin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 110, No. 8, pp. 121–124, August, 1990.