Photoperiodicity and the function of the hypophysis and the adrenal cortex

Summary The ACTH content of the hypophysis of rats rises from a minimum in the morning to a maximum in the evening hours. These fluctuations are associated with the diurnal rhythm of light and darkness, and are abolished under conditions of continual light or darkness for 30 days. Rhythmic fluctuations of the ascorbic acid content of the adrenals are also found, with maximum values in the evening, and these are likewise abolished by maintenance under conditions of constant illumination.Presented by Active Member AMN SSSR V. V. Parin     

Anatomic considerations and the relationship between the piriformis muscle and the sciatic nerve

Stating background  The piriformis syndrome is one of the non-discogenics causes of sciatica. It results from the compression of the sciatic nerve (SN) by the piriformis muscle (PM) in the neutral and piriformis stretch test position. The evidence of the increase in pain in the test position requires a detailed anatomical study addressing the changes that occurred in the SN and PM anatomy during the test position. The aim of this study is to examine this relationship morphometrically. Materials and methods  A total of 20 right and left lower limbs of ten adult cadavers were examined. The SN and the PM were made visible. The location of the SN was evaluated with respect to the consistent bony landmarks, including the greater and the lesser trochanter of the femur, the ischial tuberosity, the ischial spine of the hip bone, the posterior inferior iliac spine of the hip bone and the posterior superior iliac spine of the hip bone. The study was done in both neutral and test positions (i.e., 30° adduction 60° flexion and approximately 10° medial rotation position of the hip joint). Results  The width of the greater sciatic notch was 63.09 ± 13.59 mm. The length of the lower edge of the PM was 95.49 ± 6.21 mm, and whereas the diameter of the SN where it emerged from the infrapiriforme was 17.00 ± 3.70 mm, the diameter decreased to 11.03 ± 2.52 mm at the level of the lesser trochanter of the femur. The SN intersected the PM most commonly in its medial second quarter anatomically. The vertical distance between the medial edge of the SN–PM intersection point and the ischial tuberosity was 85.62 ± 17.23 and 72.28 ± 7.56 mm (P < 0.05); the angle between the SN and the transverse plane was 66.36° ± 6.68° and 71.90 ± 8.48° (P < 0.05); and the vertical distance between the medial edge of the SN and the apex of the ischial spine of the hip bone was 17.33 ± 4.89 and 15.84 ± 4.63 mm (P > 0.05), before and after the test position, respectively. Conclusion  This study provides helpful information regarding the course and the location of the SN. The presented morphometric data also revealed that after stretch test position, the infrapiriforme foramen becomes narrower; the SN becomes closer to the ischial spine of the hip bone, and the angle between the SN and the transverse plane increases. This study confirmed that the SN is prone to be trapped in the test position, and diagnosis of this situation requires dynamic MR and MR neurography study.     

空肠和回肠直动脉及器官表面动脉的观测

目的　通过对空、回肠直动脉分支类型的观察、测量不同类型直动脉管径、间距以及器官表面动脉吻合网面密度 ,探讨空、回肠血供形态的异同 ,为临床空、回肠疾病手术、器官移植、介入治疗提供形态学依据。方法　选取 15具成人及 2～ 6岁小儿 10具进行股动脉插管、乳胶灌注后解剖剥离直动脉 ,将空回肠均分 5段观测相关指标。结果　成人空肠 (1、2段 )及回肠 (3～ 5段 )直动脉起始处外管径 (mm)分别为 0 6 8± 0 18、0 72± 0 0 1、0 6 1± 0 0 2、0 5 3± 0 0 3和 0 5 1± 0 0 1,相邻分支间距 (mm)分别为 2 89± 1 72、2 79± 2 0 6、2 2 1± 1 6 4、2 17± 1 17及 2 85± 0 4 6 ;空、回肠直动脉长、短干型分支供血能力不同 ;空肠器官表面动脉吻合网面密度大于回肠。结论　直动脉分支类型、管径、间距及器官表面动脉吻合网面密度对空、回肠血供影响较大。     

指背腱膜滑动与近侧指间关节屈曲关系及临床意义

目的:探讨指背腱膜滑动距离与近侧指间关节(PIP)屈曲关系,为临床修复提供解剖学基础。方法:男性成人新鲜尸体标本10侧30指(示、中、环指各10指),切除手指皮肤,不破坏腱鞘、屈肌支持带、伸肌支持带、内在肌及外在肌,使肌腱保持正常的生理状态,分别测量各指中央束(CS)、侧束(LB)在PIP屈曲45°和90°时的滑动距离。结果:当PIP屈曲45°时,CS滑动距离为(2.7±0.4)mm,LB滑动距离为(2.8±0.6)mm;当PIP屈曲90°时,CS滑动距离为(4.3±0.7)mm,LB滑动距离为(4.8±0.6)mm。结论:指背腱膜滑动距离减少,严重影响手指的屈曲功能。对于指背腱膜的新鲜性损伤应予以精确修复;对于陈旧性损伤的修复应确保指背腱膜的正常滑动范围。     

岛叶与锥体束空间关系的影像学和解剖学研究

目的研究岛叶与锥体束的空间位置关系,为岛叶病变手术中保护锥体束和减少术后运动功能障碍提供指导。方法2013年3—10月,选取10例健康志愿者采用MR弥散张量纤维束成像( DTT)重建锥体束影像,选取6例成人颅脑标本运用Klingler白质纤维解剖技术解剖岛叶区域显露内囊和放射冠,在标本上进行断层解剖观察并测量岛叶标志点与内囊和放射冠的间距,结合MRI与解剖观察结果,对岛叶与锥体束的空间位置关系进行前瞻性研究。结果岛叶标志点在颅脑标本和MRI中均容易辨认。 DTT重建影像显示锥体束经过了岛叶后上部的深部。在解剖标本利用上中央岛点( UCIP)和后下岛点( PIIP)间连线将岛叶划分成前下部和后上部两个区域。岛叶后上部皮层与锥体束之间为最外囊、屏状核和外囊,而无壳核和苍白球。 UCIP和后上岛点( PSIP)距其深部的放射冠分别为(5.0依0.3)mm和(4.7依0.3)mm,PIIP距其深部的内囊后肢(5.7依0.5)mm。结论利用UCIP和PIIP连线所划分出的岛叶后上部因毗邻锥体束是手术危险区域。岛叶危险区域的划分有助于术前评估手术风险和预后,术中保护锥体束,降低术后运动功能障碍的发生率。     

Organization and distribution of the upper and lower esophageal motoneurons in the medulla and the spinal cord of the rat

The upper cervical esophagus is exerted on swallowing and peristalsis by somatic and visceral motoneurons, whereas the lower esophagus is exerted on only peristalsis by visceral motoneurons. We examined the origin of the esophageal motoneurons and whether there were any differences between the distributions of the upper and the lower esophageal motoneurons in the medulla and the spinal cord using cholera toxin subunit b (CTb) as the retrograde tracer. Following injection of CTb into the cervical esophagus resulted in heavy labeling of the neurons in the nucleus ambiguus including the compact (AmC), semicompact (AmS) and loose (AmL) formations, and the medial column of lamina IX at the C1-C5 levels of the cervical spinal cord corresponding to the spinal accessory nucleus. A few labeled neurons were found in the inferior salivatory nucleus, the rostral division of the dorsal motor nucleus of the vagus (DMX), the accessory facial nucleus and the lateral column of lamina IX at the C2 and C3 levels. All these labeled neurons showed ChAT immunoreactivity. When CTb was injected into the cut end of the unilateral recurrent laryngeal nerve, many labeled neurons were found in the ipsilateral AmC, the AmL, and the bilateral medial column at the C1 and C2 levels. Following injection of CTb into the subdiaphragmatic esophagus resulted in heavy labeling of the neurons only in the AmC and the DMX. When CTb was injected into the sternomastoid muscle, many labeled neurons were found in the medullary reticular formation, the facial nucleus, the medial column at the C1-C3, C5 and C6 levels, and the lateral column at the C2, C3, C5 and C6 levels. Injections of a Fluoro-Gold into the cervical esophagus and a CTb into the sternomastoid muscle or the subdiaphragmatic esophagus in the same animal showed many double labeled neurons in the medial column of the accessory nucleus at the C1 and C2 levels, but no double labeled neurons in the AmC. These results indicated that the upper cervical esophagus is innervated by the visceral medullary vagal motoneurons as well as the somatic spinal accessory motoneurons. The lower esophagus is innervated only by the visceral medullary vagal motoneurons.     

Cutaneous calciphylactic reactions in the mouse and the rat and the effects of diphosphonates on the reaction in the rat

Calciphylaxis is a local tissue calcific reaction at the site of an injection of challenger substance given a critical time period after the oral administration of a sensitizer substance such as dihydrotachysterol (DHT), vitamin D or parathormone. Cutaneous calciphylaxis is readily induced in the rat but not in the mouse and this may be because, in the latter, the challenger substance is absorbed rapidly by macrophages. In the rat the administration of 500 micrograms/0.1 ml of DHT followed after 24 h by the subcutaneous (SC) injection of ferric chloride (FeCl3) (30 micrograms/0.1 ml) is followed rapidly by calcification of the SC site. There is an early transient acute inflammatory reaction with the incrustation of collagen fibres by the iron salt and an apparent exudation of calcium and phosphate ions from the bloodstream. These ions also become associated with collagen fibres. Two days after injection macrophages and multinucleated giant cells become the dominant cells. Calciphylaxis is a useful experimental model of ectopic calcification and is associated with an initial hypercalcaemia. The diphosphonates ethane-1-hydroxy-1, 1-diphosphonate (EHDP) and dichloromethylene diphosphonate (Cl2MDP) are effective inhibitors of the calciphylactic reaction when administered prior to the initiation of the experimental procedure.     

Fluid calories and energy balance: the good, the bad, and the uncertain

Energy-yielding fluids are a large and growing proportion of daily energy intake. The specific form and nutrient composition of fluids may hold divergent implications for energy balance. Ethanol elicits a weak compensatory dietary response, resulting in positive energy balance. However, its impact on body weight is unclear, possibly due to metabolic inefficiencies. In contrast, the weak dietary compensation for clear beverages containing other energy sources is associated with weight gain. How these beverages elude satiety mechanisms has not been studied. Soups hold higher satiating value, at least in part, due to cognitive factors. Nutrient dense beverages have been used successfully in meal replacement regimens for weight management, but due to their relatively weak satiety value, are widely consumed for weight gain and as nutrient supplements. A better understanding of the role of fluid calories in the diet is needed to improve dietary guidelines.     

Observations on the anatomy and amine histochemistry of the nerves and ganglia which supply the pelvic viscera and on the associated chromaffin tissue in the guinea-pig

Summary The organs of the lower abdominal and pelvic regions of the guinea-pig receive nerves from the inferior mesenteric ganglia and pelvic plexuses. The inferior mesenteric ganglia connect with the sympathetic chains, the superior mesenteric ganglia, the pelvic plexuses via the hypogastric nerves, and with the gut. Each pelvic plexus consists of anterior and posterior parts which send filaments to the internal generative organs and to the rectum, internal anal sphincter and other pelvic organs. The pelvic nerves enter the posterior plexuses, which also receive rami from the sacral sympathetic chains. The adrenergic neurons of the pelvic plexuses are monopolar, do not have dendrites and are supplied by few varicose adrenergic axons. Nearly all the nerves contain adrenergic fibres. After exposure to formaldehyde vapour the chromaffin cells appear brightly fluorescent with one or two long, often varicose, processes. Most of the chromaffin cells are in Zuckerkandl's organ or in chromaffin bodies associated with the inferior mesenteric ganglia. Groups of chromaffin cells are found along the hypogastric nerves and in the pelvic plexuses; they become smaller and fewer as regions more posterior to Zuckerkandl's organ are approached.This work was supported by grants from the Australian Research Grants Committee and the National Health and Medical Research Council. We thank Professor G. Burnstock for his generous support.     

Fondaparinux: the present and the future

The development of new antithrombotic molecules which induced an inhibition of activated factor X (fondaparinux, Arixtra) shows effectiveness and safety in prevention of thromboembolic disease in surgery, but also in the treatment of the pulmonary embolism and major venous thromboses and acute myocardial infarction. Recent clinical trials show that new anti-Xa inhibitors also have interesting properties in antithrombotic therapy. Fondaparinux could offer new therapeutic possibilities that could simplify the management of patients under anticoagulant treatment.