The Prospective Assessment of Autonomic Nerve Function by Pupillometry in Adolescents with Type 1 Diabetes Mellitus

The study aimed to compare the longitudinal assessment of autonomic nerve function by computerized infrared pupillometry and standard cardiovascular tests in adolescents with diabetes. Adolescents (n = 150) were assessed at two time points (T1 and T2). The median time interval between assessments was 1.5 (range 0.9–3) years. At T1 the median age was 14.5 (range 8.3–19.5) years and the median duration was 6.5 (range 1.1–16) years. The pupillary variables assessed included the resting pupil diameter, the maximum constriction velocity, and the reflex amplitude of constriction. Heart rate reflexes were assessed in response to deep breathing, the Valsalva manoeuvre, and on standing from a lying position (30/15 ratio). Between visits there was a significant decrease in maximum constriction velocity (6.0 mm s^?1 vs 6.3 mm s^?1, p = 0.0001) and resting pupil diameter (6.2 mm vs 6.3 mm, p = 0.001). At reassessment pupillary abnormalities increased from 32 (21 %) to 45 (30%), with 17 (54 %) of the initial abnormalities persisting. Adolescents with abnormally slow maximum constriction velocity compared to those with normal maximum constriction velocity had a higher glycated haemoglobin (HbA_1c%) at T2 (p = 0.02) and between assessments (p = 0.01). Cardiovascular test abnormalities did not increase between visits and the persistence of initial abnormalities was low (21 %). In summary, pupillometry appears a more sensitive test of autonomic nerve dysfunction in adolescents with diabetes than assessment of cardiovascular reflexes.     

大鼠坐骨神经慢性挤压性损伤后痛阈和血清IL-6的变化及相关性研究

目的:通过大鼠坐骨神经慢性挤压伤(CCI)神经性疼痛模型的热敏变化及血清中IL-6含量的变化,探讨血清IL-6在神经性疼痛形成中的作用及可能机制.方法:36只250～300g的健康雄性Wistar大鼠,在戊巴比妥钠麻醉下于大腿中部暴露坐骨神经并作结扎,取对侧大腿坐骨神经暴露作为模拟对照(B组).术后1,3,5,7,9,11,13,15 d测定大鼠(n=12)两侧后爪对热敏阈值的变化.于术后第15 d处死大鼠,取血清,ELISA法测定IL-6浓度.结果:大鼠双侧后爪(CCI和B)的收缩潜伏期在术后第3,5,7,9,11,13,15 d有显著差异;CCI组血清IL-6与对照组比较有显著差异.结论:IL-6与大鼠坐骨神经慢性挤压性损伤后出现的神经源性疼痛过敏有关.     

Conduction studies in peripheral cat nerve using implanted electrodes: III. The effects of prolonged constriction on the distal nerve segment

Electrophysiological properties were monitored in detail in chronically constricted peripheral nerves by implanted, multicontact nerve cuff electrodes and correlated with morphometric histology in selected cases. The physiological and histological responses in nerve to a range of constricting cuffs of standard sizes were readily graded. The initial response to any significant constriction was a transient, focal conduction slowing or block at the constriction, followed by more protracted distal effects; the latter ranged from loss of excitability consistent with "dying-back" degeneration to reductions in conduction velocity consistent with histologically observed atrophy. Smaller myelinated fibers tended to have similar but less pronounced changes than larger diameter fibers. Recordings from ventral and dorsal roots showed that distal degeneration was more pronounced in motor than in sensory fibers of similar caliber. Electronmicroscopical measurements showed that basal laminas were relatively preserved around even the most atrophic and demyelinated axons. Perimeter measurements of the basal lamina could be used to estimate the diameter of the original nerve fiber.     

Determinants of pulmonary blood volume. Effects of acute changes in pulmonary vascular pressures and flow

To examine the effects of pulmonary vascular pressures and flow on pulmonary blood volume (PBV), experiments were performed at constant heart rate and zone 3 conditions (mean left atrial pressure (LAP) above airway pressure) in six anesthetized, open-chest dogs. PBV was calculated as the product of electromagnetic aortic flow and pulmonary mean transit time for ascorbate, obtained without blood withdrawal by polarographic recording of aortic ascorbate changes. In three series of experiments LAP was raised similarly in three steps, from 4.5 to 14.8 mmHg: by mitral constriction which reduced pulmonary blood flow, by blood volume expansion which more than doubled pulmonary blood flow, or by a combination of the two procedures which kept pulmonary blood flow constant. In all three series, LAP and mean pulmonary arterial pressure (PAP) rose in proportion, but PBV was better correlated to PAP (r=0.87±0.02) than to LAP (r=0.66±0.09). These experiments suggest that PAP is the most important factor in determining PBV under zone 3 conditions, whether PAP is raised by increasing pulmonary blood flow or by mitral constriction.     

Congenital Pseudarthrosis of Femur and Sciatic Nerve Palsy with Congenital Constriction Band Syndrome: Report of the First Case in Literature

Congenital constriction band syndrome has varied clinical presentations ranging from small, incomplete skin deep constriction band to in utero amputation. Pseudarthrosis of underlying bone most commonly tibia has been reported by many authors. We report the first case of congenital pseudarthrosis of the femur with congenital constriction band syndrome. Nine-day-old female presented with the constriction band in the left thigh with open pseudarthrosis of the femur. The left femur had gross recurvatum deformity and the posterior apex of the pseudarthrosis was exposed via skin ulceration. She had an ipsilateral paralytic clubfoot. She was treated with single-stage excision of constriction band and Z-plasty. Spontaneous union of the femur was achieved at 3 months. Procurvatum deformity of the femur improved gradually over 3 years. This happens to be the first and only reported case of congenital pseudarthrosis of the femur with sciatic nerve palsy due to congenital constriction band.     

Mulibrey nanism: Three additional patients and a review of 39 patients

We report on 3 patients with Mulibrey nanism (MN), or Perheentupa syndrome: the first 2 sibs from Argentina and a new patient from Spain. All 3 patients had growth failure, short stature, abnormal pigmentary retinal changes, and a J-shaped sella turcica. These findings are considered major criteria of MN. Two had pericardial constriction, which is a frequent and lifethreatening abnormality in this syndrome. MN is a rare autosomal recessive condition. Reviewing the 39 patients described so far, we have classified the anomalies into the very frequent (present in more than 66%), frequent (in at least 25%), and not frequent. Identifying the anomalies specific to MN should help its early diagnosis and treatment. © 1995 Wiley-Liss, Inc.     

Experimental approach to the pathogenesis of the anomalies of amniotic disease

By intra-adnexal injection of glucose in the rabbit embryo, we were able to stimulate all the anomalies associated with "Amniotic Disease". Since we were even able to obtain amniotic bands, this study provides an excellent experimental model of this disease. Resulting lesions occur early in development, corresponding to the first trimester of human gestation. All of the anomalies can ultimately be explained by the destruction of the most superficial cells: epiblastic cells of the embryo and the amnion, subjacent mesenchyme, and endothelial cells. The subsequent lack of interaction between these cells and the importance of the anatomical localizations of resulting hematomas can lead to the pathogenetic approach to this disease. In light of the present study, the disease appears to be caused by an external factor within the amniotic fluid. The exact nature of the destructive agent(s) remains a mystery in man.     

大豆苷元对豚鼠胆囊收缩运动及机制的研究

目的:研究大豆苷元对胆囊收缩运动的影响及其机制.方法:以豚鼠离体胆囊肌条收缩强度为指标,观察不同浓度的大豆苷元对豚鼠离体胆囊肌条自发性收缩及其对乙酰胆碱、组织胺、高K 和高Ca2 所致胆囊收缩运动的影响.结果:大豆苷元能显著抑制豚鼠离体胆囊肌条的自发性收缩活动,使收缩力降低,紧张性下降,且呈量效反应关系.大豆苷元还可明显拮抗乙酰胆碱、组胺、高K 所致胆囊收缩运动及拮抗累积Ca2 引起豚鼠离体胆囊收缩运动.结论:大豆苷元能显著抑制豚鼠离体胆囊自发性收缩,此作用可能与拮抗胆碱能受体、组胺受体、高K 、Ca2 或对豚鼠离体胆囊平滑肌的直接作用有关.     

腹主动脉缩窄大鼠心功能的动态变化及参附颗粒对其影响

目的观察缩窄腹主动脉致大鼠心力衰竭过程中心功能的动态变化和参附颗粒对实验性心力衰竭的防治作用。方法采用8号注射器针头行大鼠腹主动脉缩窄术。分为术后12周组、30周组和40周组,其中术后40周组又分为模型组,参附颗粒高、中、低剂量组(剂量分别为4.2、2.1、1.0g/kg),阳性药马来酸依那普利组(1.0mg/kg)。于术后30周给药,连续10周。上述各组分别于术后12、30和40周检测大鼠心功能、左心室质量(left ventricular weight,LVM)、血清脑钠素(brain natriuretic peptide,BNP),并计算左心室质量指数(left ventricular mass index,LVMI)。结果腹主动脉缩窄术后12周,模型组大鼠LVM、LVMI明显增加;术后30周模型组左心室舒张末期内压(left ventricular end-diastolic pressure,LVEDP)明显升高,左心室内压最大下降速率(maximal descending rate of left ventricular pressure,-dp/dtmax)明显下降;术后40周模型组-dp/dtmax和左心室压力最大上升速率(maximal developing rate of left ventricular pressure,+dp/dtmax)明显下降,BNP明显升高;参附颗粒组LVSP、±dp/dtmax明显增加,LVEDP和BNP明显下降。结论采用8号针头缩窄大鼠腹主动脉后,大鼠先出现心肌肥厚,30周大鼠心脏舒张功能下降,40周心脏收缩功能下降,出现心力衰竭,参附颗粒对压力超负荷致大鼠心力衰竭有防治作用。