Anion channels in a leaky epithelium

We have used the patch-clamp technique to characterize three anion channels in the ventricular membrane of the choroid plexus epithelium from Necturus. The most frequently occurring channel had a nonlinear IV-curve. The conductance in excised patches with 112 mM chloride at both sides was 28 pS at 0 mV, increasing towards positive membrane potentials. The selectivity ratios were P _NaP _Cl 0.1 and . SITS and furosemide (1 mM) on the inside reduces chloride flux to 0.15 and 0.37 times the control value. In attached patches, the most commonly observed channel had a conductance of 7.5 pS. The single-channel current for this channel reversed direction at 15 mV hyperpolarization, indicating accumulation of chloride to a factor of 1.8 above equilibrium. External stimulation of the tissue by theophylline, IBMX and dbcAMP, or by hypotonic shock did not increase the activity of this channel. In very few excised patches, we have observed a chloride channel with a conductance of 7 pS with 112 mM chloride at both sides. The 7 pS channel appears to be identical to a 2 pS channel found in attached patches. The 2 pS channel was not normally active in attached patches but was activated in 28% of the patches by external stimulation. Finally, in few excised patches we have found a 375 pS channel which inactivates within seconds when membrane potential is stepped from 0 mV to a value that differs more than 10–20 mV from zero. The channel did not conduct gluconate but and P _NaP _Cl 0.1. Internal SITS and furosemide (1 mM) reduced chloride flux to 0.3 and 0.5 times the control value. The channel was never seen in attached patches. The current carried through these channels can not account for the transepithelial steady state Cl^–-flux measured by microelectrodes. KCl exit from the cell is suggested to be carried by KCl-cotransport or by channels that are too small to be seen in patch-clamp experiments.     

Neurolysis of celiac plexus and splanchnic nerve under ultrasonographic guidance

Key words  intractable pain - celiac plexus neurolysis - ultrasonography     

The middle collateral artery: anatomic basis for the “extreme” lateral arm flap

The vascularization of the posterolateral area of the arm is supplied by the terminal branches of the deep brachial artery [middle collateral artery (MCA) and posterior radial collateral artery]. Their anatomy has been a field of confusion for a long time. An extended lateral arm flap, named the extreme lateral arm flap, supplied by these branches and dissected as a retrograde island flap has been proposed as an alternative for large compound defects of the distal forearm. We carried out an extensive anatomic study of the extreme lateral arm flap on 69 upper limbs: 54 fresh injected with colored latex, 10 embalmed and 5 radiographed after Micropaque injection. Two origin levels of the MCA were found: a proximal one (37%) above the radial groove, and a distal one (63%) at the level of the groove. The deep brachial artery always bifurcated after the origin of the MCA into a posterior radial collateral artery (PRCA) and anterior radial collateral artery (ARCA). Indeed in our dissections, after the origin of the MCA from the deep brachial artery, there was always a common trunk named the radial collateral artery (RCA) which bifurcated into the ARCA and PRCA. In all dissected arms we always found the MCA anastomosed in a transverse pattern with the inferior ulnar collateral artery (IUCA), contributing to the anastomotic circle of the elbow. This circle represents the unique vascularization source of the reverse extreme lateral arm flap.     

腰丛神经的数字化解剖及其临床意义

目的:对腰丛及其周围的组织结构进行可视化的研究,为微创手术提供更精确的数据和解剖学资料.方法:利用“虚拟中国人“Ⅰ号女性数据集,重建腰丛及其周围组织结构的三维可视化模型.结果:通过数字人数据集重建的三维图片显示腰丛神经及其主要分支与主要血管和椎体及肾脏之间的关系,又可清楚的显示腰丛神经与腰大肌之间的关系.结论:数字人数据集可提供腰丛和周围组织器官的断层图片,为腰丛的解剖学位置及腰椎前路手术提供了形态依据.     

Structure of vascular plexuses of brain ventricles in ontogeny under normal conditions and in hypoxia

The structure of vascular plexuses of brain ventricles in newborns developed under hypoxic conditions does not correspond to gestational age. Chronic hypoxia decreases activity of succinate dehydrogenase and iron content in vascular plexuses of brain ventricles.     

The communicating branch of the 4th cervical nerve to the brachial plexus: the double constitution, anterior and posterior, of its fibers

Twenty-four adult cadavers (48 sides) were used to investigate the incidence of a branch arising from the ventral ramus of the fourth cervical nerve (C4) with the phrenic nerve and subsequently joining the brachial plexus. Six brachial plexuses with spinal cords and phrenic nerves were dissected under a surgical microscope to investigate localization of fibers contained in the C4 branch to the brachial plexus. The incidence of the C4 branch was 23% (11/48 sides). Branches from C4 to the brachial plexus divided into anterior and posterior divisions on four sides (4/6 sides). On two sides, the branch did not divide but consisted entirely of an anterior division (2/6 sides). In the brachial plexus, anterior division fibers of the C4 branch were intertwined with fibers from the anterior divisions of the ventral rami of the fifth and sixth cervical nerves. They then passed to the suprascapular nerve and the anterior division of the superior trunk (6/6 sides). On the other hand, posterior division fibers of the C4 branch were intertwined with fibers from the posterior divisions of the ventral rami of the fifth and sixth cervical nerves. They then passed to the suprascapular nerve (2/6 sides) and the posterior division of the superior trunk (4/6 sides). The anterior division of the C4 branch received fibers from the ventral rootlets of the entire fourth cervical segment, whereas the posterior division received fibers from the ventral rootlets of the caudal half of the fourth cervical segment only. The fact that the suprascapular nerve received fibers from both the anterior and posterior divisions of the C4 branch was considered to support our claim that the human suprascapular nerve belongs to both the anterior and posterior divisions of the brachial plexus.     

带臂外侧上皮神经及其营养血管筋膜皮瓣的应用解剖

目的:为带臂外侧上皮神经及其营养血管筋膜皮瓣提供解剖学基础.方法:32例经灌注红色乳胶的成人上肢标本,对臂外侧上皮神经及其营养血管等进行了较详细的应用解剖学研究.结果:臂外侧上皮神经在均由腑神经发出,起点横径为1.5±0.4mm,在三角肌深方斜向外下3.6±1.1cm从该肌后缘中1/3浅出肌间隔,分为上支和下支,分布于三角肌后部、外侧部和臂外侧上部.该神经的营养血管起源于旋肱后动脉,起点外径为0.9±0.4mm;其行程、分支和分布均同在神经,供血范因为14.8×9.8cm~2,并与周围的皮动脉存在丰富吻合.结论:带臂外侧上皮神经及其营养血管筋膜皮 瓣可视受区需要设计成游离瓣或旋转瓣,用于修复邻近部位、手或颌面部缺损.     

Neu-Laxova syndrome: Prenatal ultrasonographic diagnosis,clinical and pathological studies,and new manifestations

A diagnosis of the Neu-Laxova syndrome (NLS) was made by ultrasonography at 32 wks of gestation. Ultrasonographic examination showed intrauterine growth retardation (IUGR), Dandy-Walker anomaly, choroid plexus cysts, receding forehead and microcephaly, bilateral cataract without prominent eyes, scalp edema with no generalized edema, retrognathia, curved penis, and flexion deformities of limbs. The findings in this case are consistent with NLS; however, they did not fit any of Curry's [1982] groups. Massive swelling of hands and feet were among the main manifestations in classic NLS cases. In the case presented herein, edema was noted only in the scalp. This might shed further light on the question of variability vs. heterogeneity in the NLS. This case shows the existing possibility of an early diagnosis of NLS and adds Dandy-Walker anomaly and choroid plexus cysts as new findings to this syndrome. © 1992 Wiley-Liss, Inc.     

臂丛神经损伤的磁刺激运动诱发电位

对12例臂丛神经损伤患者进行了磁刺激运动诱发电位(MEP)的测定,并与同时进行的肌电图(EMG)、神经传导速度(NCV)进行了比较,结果发现MEP的阳性率与EMG近似,对臂丛神经损伤的定位及鉴别诊断有意义。     

Morphogenesis of the primary arterial trunks of the forelimb in the rat embryos: the trunks originate from the lateral surface of the dorsal aorta independently of the intersegmental arteries

It has been believed that the primary arterial trunk of the mammalian forelimb is derived from the 7th intersegmental artery. Here we examined the early morphogenesis of the arteries and nerves in the forelimb region by adopting a method that combined intravascular dye-injection with nerve staining to whole mounted rat embryos. The study was carried out on greater numbers of specimens at smaller intervals of embryonic stages and from earlier stages than those in previous reports. We report that: (1) The multiple primary arterial trunks in the forelimb region (primary subclavians) originate directly from the lateral surface of the dorsal aorta independently of the intersegmental arteries, previous to the formation of limb buds. (2) The tips of the 8th (and the 9th) primary subclavians that originate from the aorta near the origin of the 8th (or the 9th) intersegmental artery bend cranially and/or caudally. With the formation of limb bud, they extend to form the longitudinal trunks in the presumptive axillary region. The primary arteries in the free arm region branch off from this longitudinal trunk, and one of them develops into the axial artery. (3) The origins of the primary subclavians shift their positions on the surface of the dorsal aorta and approach the origins of the neighboring intersegmental arteries to join them, and then replace the latter. Consequently, the primary subclavians appear to be ”the lateral branches of the in tersegmental arteries.” (4) The 8th primary subclavian is dominant at first, but is replaced by the 7th primary subclavian, which develops into the definitive subclavian artery. (5) With the brachial nerve plexus formation, the axillary arterial plexus derived from the longitudinal trunk develops to form two stems of the axillary artery. Accepted: 15 April 1999