An anatomical method for re-siting the umbilicus

The umbilicus is the only normal scar on the body and it is the most noticeable scar following abdominoplasty and TRAM or DIEP flap procedures. We describe a technique for resiting the umbilicus that attempts to recreate the anatomical structure by attaching the superficial fascia to the periumbilical skin to produce a fullness around the depression in which the umbilicus sits. This is aesthetically desirable and avoids the uncomfortable tethering of the umbilicus to the rectus sheath associated with other techniques.     

The extended vertical rectus abdominis myocutaneous flap for breast reconstruction

The extended vertical rectus abdominis myocutaneous flap has been used in 34 patients for breast reconstruction after radical mastectomy. This flap can reconstruct a large ptotic breast mound and fill the infraclavicular and axillary areas. The operative technique and a discussion of the method are presented. There are several advantages to the extended vertical rectus abdominis myocutaneous flap. First, the main advantage of this flap is its reliable vascular supply, which can reach to the infraclavicular and axillary areas. Second, the large volume of this flap can reconstruct the large ptotic breast, fill the infraclavicular hollow, and create an axillary fold. Third, no lower abdominal wall hernias have developed, and use of alloplastic abdominal wall reinforcement is not necessary. Finally, the simultaneous beneficial effect of horizontal abdominoplasty, which further enhances the patient's body image by narrowing the waist, is unique to this vertical abdominal flap. The disadvantages of this flap include (1) the midline abdominal scar, (2) an umbilical scar on the reconstructed breast, and (3) in principle, inappropriateness for the patient who desires pregnancy postoperatively.     

Pfannenstiel incision as an alternative approach for harvesting the rectus abdominis muscle for free-tissue transfer

The rectus abdominis muscle has been one of the most commonly used donor tissues for free-flap reconstruction of defects in the extremities and in selected head and neck patients. The rectus abdominis has provided adequate soft-tissue mass with predictable anatomy and results for the majority of its applications in free-flap reconstruction. Harvesting of this muscle has typically been done through a paramedian or midline incision, which has left a lengthy notable scar on a patient's abdomen. To avoid the late aesthetic deformity associated with this typical approach for the rectus abdominis, we began harvesting the muscle through a Pfannenstiel incision. Patients were initially selected based on young age and limited soft-tissue requirements. With additional experience, this technique was extended to include all healthy patients regardless of age. Also, soft-tissue limitations no longer became an issue, as we learned the entire rectus abdominis muscle could be harvested from this approach. An extended Pfannenstiel incision was made from the ipsilateral anterior superior iliac spine to the lateral border of the contralateral rectus abdominis. A superiorly based flap was raised to expose the full length of the anterior rectus sheath from pubis to costal margin. In our earlier patients, a periumbilical incision was made for presumed easier access, but we discovered this was an unnecessary maneuver. With the anterior sheath fully exposed, the muscle was harvested and the sheath repaired in a routine manner. The elevated abdominal flap was returned to its anatomic position and closed over a suction drain. Since 1993, 10 patients have undergone a Pfannenstiel approach for harvesting of the rectus abdominis muscle. The mean age was 16. The areas requiring coverage included a traumatic elbow defect, seven traumatic lower extremity defects, one lower extremity sarcoma defect, and one lower extremity septic joint defect. Mean follow-up for these patients was 12 months. There were no flap failures. One patient developed an arterial thrombosis on postoperative day 5 and was treated with successful revision. There were no abdominal wall complications. Cosmesis was judged as good in all patients. We would recommend avoiding this approach in heavy or moderate smokers, diabetic patients, and patients with significant obesity. The Pfannenstiel approach to the rectus abdominis muscle has allowed for complete harvest of the muscle, improved aesthetic results compared with alternative techniques, and avoidance of donor-site morbidityin healthy patients.     

Simplified technique for creating a youthful umbilicus in abdominoplasty

Reimplantation of the umbilicus remains a critical aesthetic component in abdominoplasty and transverse rectus abdominis musculocutaneous breast reconstruction. Although the ideal shape of the umbilicus has been debated, recent studies have shown the young, thin female with an attractive abdomen tends to have a small, vertically oriented umbilicus. The aesthetic considerations for reimplantation include position, depth, shape, and location of scar. The authors present a technique that is expedient and reliable and that addresses each of these variables. The umbilicus is sutured to the rectus fascia and reimplanted through a vertical incision in the abdominal flap. Subdermal sutures are placed from the umbilicus to the linea alba superiorly and inferiorly. These sutures create a vertically oriented shape and place the umbilicus in the midline. Shortening the umbilical stalk establishes depth and hides the closure of the umbilicus and abdominal flap within the stalk. The stalk length is easily varied, depending on the thickness of the panniculus. Defatting is performed through the vertical incision to allow easy visualization of the umbilicus. This technique creates depth, ensures optimal position, pulls the scar deep in the umbilicus, and produces a vertically oriented, youthful umbilicus. More importantly, a questionnaire given to patients who have undergone abdominoplasty with this procedure (n = 21) confirms that patients have a high level of satisfaction with the resulting shape, position, and overall appearance.     

股直肌、股外肌在坚持“虚步”过程中表面肌电图振幅与频率的定量分析

本文目的在于用定量分析技术研究虚步练习的疲劳过程中表面肌电图振幅与频率的变化。 实验发现坚持虚步直至疲劳过程中,股直肌与股外肌的IEMG均出现增加,肌电图功率谱向低频转移,及MPF减少。 股直肌与股外肌相比,坚持虚步过程中股直肌的IEMG较股外肌增加更为明显,而MPF的变化股外肌较股直肌更为显著。 此外,还观察到股外肌与股直肌肌电活动的“迁移”,即开始时股外肌电活动较股直肌强(肌电活动比为6∶4),以后逐渐过渡到二者的肌电活动相等(5∶5)。 文中着重讨论了股直肌、股外肌肌电图变化不同的原因。我们认为这可能由于股外肌在完成虚步练习中较股直肌起着更大的作用。     

Umbilical reconstruction after repair of omphalocele and gastroschisis

This article presents our technique of umbilical reconstruction after the repair of omphalocele and gastroschisis. We have treated 8 patients with an average follow-up period of 13 months (range, 6 approximately 24 months). No major complications have occurred; minor complications have included delayed wound healing, decreased umbilical depth, and hematoma. Our procedure is especially useful for patients who have a midline abdominal scar and relatively intact bilateral rectus abdominis muscles. Most of the patients and their parents have been satisfied with the results of umbilical reconstruction.     

Mechanisms of improved knee flexion after rectus femoris transfer surgery

Rectus femoris transfer is frequently performed to treat stiff-knee gait in subjects with cerebral palsy. In this surgery, the distal tendon is released from the patella and re-attached to one of several sites, such as the sartorius or the iliotibial band. Surgical outcomes vary, and the mechanisms by which the surgery improves knee motion are unclear. The purpose of this study was to clarify the mechanism by which the transferred muscle improves knee flexion by examining three types of transfers. Muscle-actuated dynamic simulations were created of ten children diagnosed with cerebral palsy and stiff-knee gait. These simulations were altered to represent surgical transfers of the rectus femoris to the sartorius and the iliotibial band. Rectus femoris transfers in which the muscle remained attached to the underlying vasti through scar tissue were also simulated by reducing but not eliminating the muscle's knee extension moment. Simulated transfer to the sartorius, which converted the rectus femoris’ knee extension moment to a flexion moment, produced 32±8° improvement in peak knee flexion on average. Simulated transfer to the iliotibial band, which completely eliminated the muscle's knee extension moment, predicted only slightly less improvement in peak knee flexion (28±8°). Scarred transfer simulations, which reduced the muscle's knee extension moment, predicted significantly less (p<0.001) improvement in peak knee flexion (14±5°). Simulations revealed that improved knee flexion following rectus femoris transfer is achieved primarily by reduction of the muscle's knee extension moment. Reduction of scarring of the rectus femoris to underlying muscles has the potential to enhance knee flexion.     

Effects of postural changes and vestibular lesions on diaphragm and rectus abdominis activity in awake cats.

Changes in posture can affect the resting length of the diaphragm, requiring alterations in the activity of both the abdominal muscles and the diaphragm to maintain stable ventilation. To determine the role of the vestibular system in regulating respiratory muscle discharges during postural changes, spontaneous diaphragm and rectus abdominis activity and modulation of the firing of these muscles during nose-up and ear-down tilt were compared before and after removal of labyrinthine inputs in awake cats. In vestibular-intact animals, nose-up and ear-down tilts from the prone position altered rectus abdominis firing, whereas the effects of body rotation on diaphragm activity were not statistically significant. After peripheral vestibular lesions, spontaneous diaphragm and rectus abdominis discharges increased significantly (by approximately 170%), and augmentation of rectus abdominis activity during nose-up body rotation was diminished. However, spontaneous muscle activity and responses to tilt began to recover after a few days after the lesions, presumably because of plasticity in the central vestibular system. These data suggest that the vestibular system provides tonic inhibitory influences on rectus abdominis and the diaphragm and in addition contributes to eliciting increases in abdominal muscle activity during some changes in body orientation.     

Abdominal wall reconstruction with an expanded rectus femoris flap

The expanded rectus femoris flap has several advantages for massive abdominal wall reconstruction. The expanded flap can easily reach the xyphoid, and it has impressive width. The donor site can be closed primarily with an acceptable scar. The muscle remains innervated and functional, which may help prevent bulging. When performing the surgery in conjunction with intra-abdominal procedures, such as fistula repair, a simultaneous two-team approach can be used without awkward positioning. The expansion provides some thinning of the muscle, providing a contour more like that of the native abdomen. Its use should be considered in cases of abdominal wall defects extending above the umbilicus.     

In vivo motion of the rectus femoris muscle after tendon transfer surgery

Rectus femoris transfer surgery is performed to convert the rectus femoris muscle from a knee extensor to a knee flexor. In this surgery, the distal tendon of the rectus femoris is detached from the patella and reattached to one of the knee flexor tendons. The outcomes of this procedure are variable, and it is not known if the surgery successfully converts the muscle to a knee flexor. We measured the motion of muscle tissue within the rectus femoris and vastus intermedius during knee extension in 10 unimpaired control subjects (10 limbs) and 6 subjects (10 limbs) after rectus femoris transfer using cine phase-contrast magnetic resonance imaging. Displacements of the vastus intermedius during knee extension were similar between control and tendon transfer subjects. In the control subjects, the rectus femoris muscle consistently moved in the direction of the knee extensors and displaced more than the vastus intermedius. The rectus femoris also moved in the direction of the knee extensors in the tendon transfer subjects; however, the transferred rectus femoris displaced less than the vastus intermedius. These results suggest that the rectus femoris is not converted to a knee flexor after its distal tendon is transferred to the posterior side of the knee, but its capacity for knee extension is diminished by the surgery.     

Hypertrophic scar: an interruption in the remodeling of repair--a laser Doppler blood flow study.

Soft-tissue dermal loss does not regenerate; instead, it is replaced with scar. The extent of scarring is directly related to the severity of tissue loss (in terms of volume and depth). Commonly, an acute dermal loss will heal with excessive scar, hypertrophic scar. A hypertrophic scar is elevated but is contained within the boundaries of the initial injury. Hypertrophic scars have a reddish appearance, indicating an elevated local circulation. A laser Doppler blood flow monitor was employed to measure blood flow changes in healed wounds. It was speculated that local circulation in a developing hypertrophic scar would be elevated. Patients with recently healed wound sites were monitored and exhibited an average blood flow reading of 365 +/- 325 mV (n = 131). This average value, ranging from 98 to 1450 mV, was 18 times greater than the average reading from normal skin, which was 43 +/- 13 mV (n = 212). Blood flow declined to 32 +/- 21 mV (n = 7) at 16 to 18 weeks (74 percent of normal skin values) in healed wounds that developed normal scar. However, a closed wound that developed into a hypertrophic scar had a blood flow reading of 148 +/- 78 mV (n = 59) at 16 to 18 weeks. This value was three times greater than in normal skin and four times greater than in normal scar. At 38 to 50 weeks postinjury, hypertrophic scar remained elevated (102 +/- 34 mV; n = 10). Hypertrophic scars sustain an elevated blood flow.(ABSTRACT TRUNCATED AT 250 WORDS)     

Analysis of muscle activation during different leg press exercises at submaximum effort levels

Many studies have analyzed muscle activity during different strength exercises. Although the leg press (LP) is one of the most common exercises performed, there is little evidence of lower limb muscle activity patterns during this exercise and its variations. Thus, this study aimed to verify how mechanical changes and loads affect lower limb muscle activity during the performance of different LP exercises. Fourteen women performed 3 LP exercises: 45 degrees LP (LP45), LP high (LPH), and LP low (LPL) at 40% and 80% of the 1 repetition maximum. The electromyographic activity of the rectus femoris, vastus lateralis, biceps femoris, gastrocnemius, and gluteus maximus was recorded. Results suggested that mechanical changes affect lower limb muscle activity and that it is related to the load used. At moderate effort levels, the rectus femoris and gastrocnemius were more active during the LP45 and LPL than during the LPH. At a high effort level, the rectus femoris and vastus lateralis (quadriceps) were more active during the LPL than the LPH. Again, the rectus femoris and gastrocnemius were more active during the LP45 and LPL than the LPH. On the other hand, gluteus maximus activity was greater during the LPH than the LPL. This study found that coordination patterns of muscle activity are different when performing LP variations at high or moderate effort levels because of mechanical changes and different loads lifted during the different LP exercises. These results suggest that if the goal is to induce greater rectus femoris and vastus lateralis (quadriceps) activation, the LPL should be performed. On the other hand, if the goal is to induce gluteus maximus activity, the LPH should be performed.     

重组反义GFAP逆转录病毒对星形胶质细胞在胶质瘢痕增生中作用的研究

本文研究了脑穿刺损伤后伤灶组织中大胶质细胞的变化、性激素对脑损伤后星形胶质细胞反应的影响,以及反义胶质原纤维酸性蛋白（ＧＦＡＰ）逆转录病毒表达载体对Ａｓｔ形态结构,反应性胶质化及胶质瘢痕形成的作用。结果表明,胶质瘢痕中增生的大胶质细胞主要是Ａｓｔ,ＧＦＡＰ对维持Ａｓｔ的形态结构及功能具有重要作用;少突胶质细胞在胶质瘢痕形成过程中不是反应活跃的细胞成分;性激素对Ａｓｔ的反应性胶质化有一定程度的抑制作     

Metamorphosis of the feeding mechanism in tiger salamanders (Ambystoma tigrinum): the ontogeny of cranial muscle mass

Most previous research on metamorphosis of the musculoskeletal system in vertebrates has focused on the transformation of the skeleton. In this paper we focus on the transformation of the muscles of the head during metamorphosis in tiger salamanders ( Ambystoma tigrinum ) in order (1) to provide new data on changes in myology during ontogeny, and (2) to aid in interpreting previous data on the metamorphosis of function in the head of salamanders.
The physiological cross-sectional area of nine head muscles was calculated by measuring fibre angles, fibre lengths, and muscle mass in two samples of tiger salamanders obtained just before and just after metamorphosis. The major mouth-opening muscles (rectus cervicis and depressor mandibulae) exhibit a significant decrease in estimated maximum tetanic tension (MTT) across metamorphosis of about 36%. The jaw-closing muscles (adductor mandibulae internus and externus) and the head-lifting muscles (epaxials) also decrease in MTT but not significantly. The muscles associated with tongue projection during feeding on land (the subarcualis rectus I, geniohyoideus, interhyoideus and intermandibularis) all show a slight increase in MTT at metamorphosis.
Metamorphic transformation of feeding behaviour in Ambystoma tigrinum involves changes in performance, the design of skeletal elements, changes in muscle force-generating capability, and changes in hydrodynamic design from unidirectional flow in larvae to bidirectional flow during aquatic feeding after metamorphosis. Although muscle activity patterns during aquatic feeding do not change across metamorphosis, tongue-based terrestrial feeding involves a suite of novel muscle activity patterns, morphological characters acquired at metamorphosis, and a metamorphic increase in the masses of muscles important in tongue projection.     

miR-21在疤痕形成中的作用及其机制研究

目的:探究mi R-21在疤痕形成中的作用及其相关机制。方法:选取2016年3月-2017年8月在本院就诊的20例皮肤有疤痕患者,采集患者的正常皮肤组织(正常组)、疤痕组织(疤痕组),进行成纤维细胞的分离培养,比较正常组、疤痕组mi R-21与Smad-7的m RNA表达水平,并在疤痕组织加入mi R-21抑制剂(抑制组),比较三组成纤维细胞增殖情况、蛋白表达及磷酸化水平。结果:正常组中Smad-7的m RNA表达水平显著高于疤痕组,而mi R-21的m RNA水平显著低于疤痕组,差异均有统计学意义(P0.05)。细胞培养48 h和72 h时,疤痕组成纤维细胞增殖水平明显高于正常组和抑制组,差异有统计学意义(P0.05),而抑制组和正常组成纤维细胞增殖水平比较差异无统计学意义(P0.05)。疤痕组成纤维细胞Smad-7蛋白表达低于正常组和抑制组,差异有统计学意义(P0.05),疤痕组成纤维细胞Smad-2、Smad-3蛋白表达及磷酸化水平均高于正常组和抑制组,差异有统计学意义(P0.05)。结论:疤痕组织中mi R-21通过负调控Smad-7的表达,从而引起Smad-2与Smad-3蛋白表达发生变化,使得疤痕成纤维细胞的增殖水平明显增高,最终促成疤痕的形成。     

Response of motor units of the abdominal musculus rectus to afferent input in the course of the long-lasting activity in rats

In rats, in the course of a long-lasting m. rectus abdominis motor units activity combined with repetitive afferent stimulation of the ischiadic nerve, the units' firing rate decreased. The dependence of the motor units response to afferent stimulation on the background firing rate was preserved during the long-lasting activity in spite of changes in the background firing rate.     

Effect of hypercapnia and PEEP on expiratory muscle EMG and shortening

The present study examined the effects of hypercapnia and positive end-expiratory pressure (PEEP) on the electromyographic (EMG) activity and tidal length changes of the expiratory muscles in 12 anesthetized, spontaneously breathing dogs. The integrated EMG activity of both abdominal (external oblique, internal oblique, rectus abdominis, and transverse abdominis) and thoracic (triangularis sterni, internal intercostal) expiratory muscles increased linearly with increasing PCO2 and PEEP. However, with both hypercapnia and PEEP, the percent increase in abdominal muscle electrical activity exceeded that of thoracic expiratory muscle activity. Both hypercapnia and PEEP increased the tidal shortening of the external oblique and rectus abdominis muscles. Changes in tidal length correlated closely with simultaneous increases in muscle electrical activity. However, during both hypercapnia and PEEP, length changes of the external oblique were significantly greater than those of the rectus abdominis. We conclude that both progressive hypercapnia and PEEP increase the electrical activity of all expiratory muscles and augment their tidal shortening but produce quantitatively different responses in the several expiratory muscles.     

Anatomy of a cline: dissecting anti‐predatory adaptations in a marine gastropod along the U.S. Atlantic coast

The scope of anti‐predatory adaptation is expected to be greater in warm than in cold environments. High temperatures lower the costs associated with the production and maintenance of energetically expensive traits and enable ecological interactions to intensify. We tested this hypothesis by characterizing the expression of anti‐predatory morphology within a marine gastropod species (the knobbed whelk Busycon carica) over a large (> 1400 km) geographic area that spans more than 10°C annual temperature variation. We also conducted experimental predation studies with a powerful durophagous predator, the stone crab Menippe, to verify the anti‐predatory advantages of a heavily ornamented shell morphology (e.g. increased thickness, pronounced spines), and we used repair scar data to assess clinal variation in selective pressure from predators. We predicted that repair scar rates would be greatest in warm southernmost latitudes, and that expression of energetically costly anti‐predatory morphology would peak in concert with elevated predation pressures. Experiments confirmed that whelks with energetically costly, heavily ornamented shells had higher survivorship rates than those with weakly ornamented shells. As predicted, we also found that the expression of anti‐predatory traits was greatest in the southern part of B. carica's range. After standardizing shells for size, shape, and exposure time to enemies, repair scar rates also peaked to the south. Taken together, these results suggest that the expression of anti‐predatory traits along the geographic cline is governed by the interaction of two selective factors: temperature and predation, with the former acting as the ultimate control on the scope of adaptation both by escalating predation pressure in the southern part of B. carica's range and by physically limiting (to the north) and facilitating (to the south) the production of anti‐predatory traits. Feedbacks between temperature and predation thus causally interact to enable and drive, respectively, the observed geographic cline in energy‐intensive anti‐predatory shell traits.