不同置换液量血液透析滤过治疗尿毒症皮肤瘙痒疗效观察

目的：观察不同置换液量血液透析滤过(HDF)对尿毒症皮肤瘙痒的治疗作用。方法：将30例并发皮肤瘙痒的维持性血液透析尿毒症患随机分为三个组，分别接受高置换液量后稀释HDF(置换液20L)、低置换液量后稀释HDF(置换液10L)和高通量血液透析治疗。均使用F60透析器，隔日1次，连续3次，其余治疗条件相同。对皮肤瘙痒症状定量计分，比较三组病人治疗前后皮肤瘙痒症状积分的改变以及血磷和甲状旁腺激素(PTH)的变化。结果：高置换液量HDF组治疗后皮肤瘙痒积分明显下降，有统计学意义。其余两组无差异。以皮肤瘙痒积分下降50％为有效计算，高置换液量HDF组7例有效，有效率70％；低置换液量HDF组3例有效。有效率30％；透析组1例有效，有效率10％。三组间比较有统计学差异。三组透析后血磷均明显下降，有统计学意义；PTH亦有下降，HDF组有统计学差异，HD组无统计学差异。结论：增加置换液量可以提高HDF治疗尿毒症皮肤瘙痒的疗效；HDF治疗尿毒症皮肤瘙痒疗效优于高通量血液透析；HDF清除PTH的效果高于HD。     

Thoracic epidural analgesia in aortocoronary bypass surgery II: effects on the endocrine metabolic response

Thoracic epidural analgesia (TEA) may offer haemodynamic benefits for patients with coronary heart disease going through major surgery. This may – in part – be secondary to an effect on the endocrine and metabolic response to surgery. We therefore investigated the effect of TEA on the endocrine metabolic response to aortocoronary bypass surgery (ACBS).
Thirty male patients (age < 65 years, ejection fraction > 0.5) were randomized into 3 groups; the HF group receiving a high dose fentanyl (55 μg–kg^-1) anaesthesia, the HF + TEA group with the same fentanyl dose + TEA with 10 ml bupivacain 5 mg ml^-1, followed by 4 ml every hour, and the LF + TEA group receiving fentanyl 15 μg kg^-1 + TEA. Adrenalin, noradrenalin, systemic vascular resistance (SVR), glucose, Cortisol, lactate and free fatty acids were followed during the operation and for 20 h postoperatively.
A significant increase in adrenalin, noradrenalin and SVR was found in the HF group whereas this increase was blocked in both epidural groups. An increase in glucose and Cortisol was noticed in all groups, but the increase was delayed in the epidural groups.
Our results suggest that a more effective blockade of the stress response during ACBS is obtained when TEA is added to general anaesthesia than with high dose fentanyl anaesthesia alone.     

Relative weight of glucose, insulin and parathyroid hormone in the urinary loss of phosphate by chronically diabetic rats

This report deals with the relationships between glucose (G) and insulin on the tubular transport of phosphate (P) in chronically diabetic rats with high plasma levels of parathyroid hormone (PTH). Alloxan-induced diabetes leads to phosphorus depletion of the soft tissues. This phenomenon appears associated with weight loss and negative P balances caused by the increased urinary P excretion. Administration of 2 IU of insulin/100 g body weight (bw) to diabetic rats normalized their P balance and body weight. The effect of parathyroid function on the P metabolism of diabetic rats was investigated with balance experiments. Diabetic rats, intact or thyroparathyroidectomized (TPTX), have a greater urinary excretion of P than their controls. However, in control rats, the ratio intact:TPTX for urinary P is 1.0:0.76, showing the antiphosphaturic effect of parathyroid ablation. For diabetic animals, on the other hand, the ratio is 1.0:1.44. The simultaneous deficit of insulin and PTH thus quadruples the urinary P loss, instead of compensating for each other. The contribution of insulin deficit and hyperglycemia to the defect in tubular reabsorption (TRP) was investigated with clearance experiments (done on anesthetized, perfused rats). Five experimental groups were used: Controls (C), diabetics (D), controls+glucose (C+G), diabetics+insulin (D+I) and diabetics+insulin+glucose (D+I+G). All experimental groups showed a linear relationship between the TRP of P and G. The regression equation for C is significantly different (F=40.1, P<0.001) from that of D animals. The slope value measure the number of μmoles of P per μmol of G reabsorbed. For C and D rats, the ratio P:G approximates 1:4 and 1:20, respectively. The increase in P:G ratios represents the competition between both substrates for tubular resorption. Glycemias up to 11 mM (C and D+I) exist concurrent with the P:G ratio 1:4. Glycemias above 25 mM (D, C+G and D+I+G) produce a P:G ratio of 1:20. Fractional excretion of P (FEP) increased significantly in untreated, chronically diabetic rats (0.47± 0.12 vs controls=0.05±0.01, P<0.001). After a single intramuscular injection of insulin, the FEP decreased as a function of insulin levels. To normalize the FEP of diabetic rats in short-term experiments, insulin had to be administered in doses that produce plasma insulin levels 25 times greater than normal. The general information afforded by the present experiments shows that in untreated, chronically diabetic rats, insulin deficit plays an indirect role. The absence of PTH enhances the effect of hyperglycemia. The latter and the concurrent tubular overload of glucose are the cause of hyperphosphaturia in these animals. Received: 10 September 1996 / Accepted in revised form: 18 April 1997     

Total Parathyroidectomy With Autotransplantation in Haemodialysed Patients With Secondary Hyperparathyroidism--Should It Be Abandoned?

The development of secondary hyperparathyroidism is almost universalin patients with end-stage renal disease. Medical managementfrequently fails and in such circumstances parathyroidectomybecomes a necessity. Total parathyroidectomy with autotransplantationof parathyroid tissue into the patient's forearm has been advocatedas the surgical procedure of choice. In a previous publicationwe reported our experience with this technique in six haemodialysedpatients. We now extend our follow-up to 19 patients over anobservation period ranging from 6 to 66 months. Five of thesepatients required graft removal because of recurrent secondaryhyperparathyroidism. Despite total graft removal, two patientshad clinical and laboratory evidence of persistent hyperparathyroidism.Histology of the removed graft tissue demonstrated severe hyperplasiaas well as invasion of adjacent muscle, adipose tissue, andvascular channels by parathyroid cells. This raises the possibilityof local and distant metastatic spread of parathyroid tissueresulting in hyperparathyroidism. We suggest that parathyroidautotransplantation is potentially hazardous and should in factbe abandoned.     

丙氨瑞林治疗子宫内膜癌病人的性激素及有丝分裂指数的变化

目的：观察丙氨瑞林对子宫内膜癌的治疗作用。方法：对诊刮确诊的１７例子宫内膜癌病人，予丙氨瑞林７００μｇ，ｉｍ，ｑｄ×７ｄ，用药前后作性激素测定及组织学检查。结果：绝经妇女用药后血中ＦＳＨ和ＬＨ下降（Ｐ＜０．０１和＜０．０５），雌二醇、孕酮及睾丸酮变化不明显。其中１３例内膜样腺癌用药后有丝分裂指数明显下降（Ｐ＜０．０１），有丝分裂指数变化与癌周内膜之反应有关。呈增生反应癌周内膜癌组织有丝分裂指数下降值明显高于呈萎缩状态癌周内膜。结论：丙氨瑞林治疗子宫内膜癌后能降低ＦＳＨ和ＬＨ水平，对子宫内膜癌尤其是雌激素依赖性内膜癌有一定疗效。     

Left ventricle haemodynamics and vaso-active hormones during graded supine exercise in healthy male subjects

Left ventricle systolic and diastolic functional parameters were measured by gated equilibrium radionuclide cardiography in 12 healthy men (age 33–51 years) at rest and during graded supine exercise. The leftventricle end-diastolic volume showed an initial small (11%) increase during low submaximal exercise [from mean 163 (SD 40) at rest to mean 181 (SD 48) ml], while left ventricle end-systolic volume decreased successively [from mean 59 (SD 19) to mean 39 (SD 21) ml] with increasing exercise. Stroke volume was therefore elevated at all exercise levels compared with rest [mean 104 (SD 23) ml], and the peak value [mean 128 (SD 33) ml] was found at the lowest exercise level, contributing 40% to the initial increase in cardiac output. Cardiac output increased from mean 6.2 (SD 1.4) at rest to mean 20.2 (SD 5.0) 1 · min^–1 at maximum. Left ventricle peak ejection and peak filling rates increased from mean 449 (SD 89) and mean 442 (SD 85) ml · s^–1 at rest to mean 996 (SD 227) and mean 1255 (SD 333) ml · s^–1, respectively, at maximum. The myocardium oxygen consumption, assumed to be proportional to the sum of the stroke work and the potential energy, increased fourfold, but absolute values were twice as high as expected, indicating that extrapolation from data obtained in dog hearts (as we have done) cannot be directly applied to humans. Selected vaso-active hormones were measured at all exercise intensities. Noradrenaline (NA), adrenaline (A) and angiotensin II (AII) concentrations showed a very pronounced increase at maximal exercise compared with the preceding lower intensites, while atrial natriuretic factor (ANF) and cyclic guanosinemonophosphate (cGMP) concentrations showed a more continuous increase, and dopamine (DA) remained almost unchanged. This speaks in favour of a crucial role for NA, A and AII in preserving blood pressure at maximum exercise, while DA probably has no importance for the cardiovascular homeostasis during exercise. Increases in concentrations of ANF and cGMP were highly correlated (r = 0.86). Our data supported the opinion that there is a cardiac limitation to maximal performance connected to the cardiac pumping capacity.     

Proteolytic Processing Mechanisms in the Biosynthesis of Neuroendocrine Peptides: The Subtilisin-like Proprotein Convertases

The recent discovery of a novel family of precursor processing endoproteases has greatly accelerated progress in understanding the complex mechanisms underlying the maturation of prohormones, neuropeptides, and many other precursor-derived proteins. At least six members of this family have been found thus far in mammalian species, several having alternatively spliced isoforms, and related enzymes have been identified in many invertebrates, including molluscs, insects, nematodes, and coelenterates. The proprotein convertases are all dependent on calcium for activity and all possess highly conserved subtilisin-like domains with the characteristic catalytic triad of this serine protease (ordered Asp, His, and Ser along the polypeptide chain). Two members of this family, PC2(SPC2) and PC1/PC3(SPC3), appear to play a preeminent role in neuroendocrine precursor processing. Both convertases are expressed only in the brain and in the extended neuroendocrine system, while another important family member—furin/PACE (SPC1)—is expressed more ubiquitously, in almost all tissues, and at high levels in liver. SPC2 and SPC3 exhibit acidic pH optima and other properties which enhance their activity in the acidic, calcium-enriched environment of the dense-core secretory granules of the regulated pathway in neuroendocrine cells, while furin has a neutral pH optimum and is localized predominantly to the trans Golgi network where it is retained by a C-terminal transmembrane domain. Furin processes a wide variety of precursors in the constitutive pathway, such as those of growth factors, receptors, coagulation factors, and viral glycoproteins. Recent findings on the processing of proopiomelanocortin, proinsulin, proglucagon, and several other neuroendocrine precursors by SPC2 and SPC3 are discussed, along with information on the structure, properties, evolution, developmental expression, and regulation or the convertases. An inherited defect in the fat/fat mouse which affects the processing of proinsulin, and probably also many other prohormones, due to a point mutation in carboxypeptidase E has recently been identified and has begun to provide new insights into the functional integration of the individual processing steps.     

The effects of brisk walking on markers of bone and calcium metabolism in postmenopausal women

Weight-bearing exercise has been shown to maintain or increase bone mass in younger as well as older individuals but the mechanisms by which mechanical loading affects bone metabolism are not known in detail. Twelve postmenopausal women participated in a single bout of brisk walking (50% of VO_{2 max}) for 90 minuttes. Calciotropic hormones and markers of type I collagen formation (PICP) and degradation (ICTP) were measured before the exercise, and 1, 24, and 72 hours following the exercise. Total body bone mineral content (BMC) and density (BMD) were measured by dual energy X-ray absorptiometry (DXA). Brisk walking did not induce any significant changes in the concentrations of ionized calcium, parathyroid hormone (PTH), calcitonin, or osteocalcin. A significant increase of PICP was noted 24 and 72 hours (P<0.01) after exertion and a significant decrease in the concentration of serum ICTP at 1 hour (P<0.05) was followed by an increase at 72 hours (P<0.001). There was no significant difference between the increases in the concentrations of PICP and ICTP at 72 hours. Strong inverse correlations between the basal levels of PTH and BMD (r=−0.78;P<0.01) as well as between osteocalcin and BMD (r=−0.83;P<0.01) were noticed. The changes in serum levels of bone collagen markers indicate an altered bone collagen turnover due to this moderate endurance exercise. The results also support the fact that serum levels of PTH as well as those of osteocalcin are associated with total body BMD in postmenopausal women.     

男性胆囊结石患者血清性激素和前列腺素改变的探讨

借助RIA,对28例胆囊结石男性(平均57.5岁)及26名健康中、老年男性(平均63.3岁)进行了血清雌二醇(E_2)、孕酮、睾酮和前列腺素类(PGs)检测,以探索胆石形成机理。结果,1)在胆石男病人中.平均E_2和平均孕酮水平均高,他们的平均睾酮则低下,与健康对照男性相应诸值比较,差异非常显著或显著(P<0.001,0.05,0.05);2)至于平均PGs,胆石男性组者与健康对照男性相比,前者也相当高(23.01pg/ml对16.31pg/ml),只是两组间差异尚无统计学意义。作者等初步设想,胆石男性小,如同胆石女性那般,本症也可能是某种垂体性腺激素分泌紊乱性疾病。     

不同强度运动对女子游泳运动员性激素水平的影响及特点

本研究以放兔分析法观察不同强度运动前后19名女子游泳运动员血清促卵泡激素(FSH)、黄体生成素(LH)、雌二醇(E_2)、孕酮(P)、睾酮(T)及胰岛素(Ins)的变化。受试者在卵泡及黄体两期分别进行短时间高强度间歇运动——6×50m全速力竭性游泳和长时间持续运动——1000m全速力竭性游泳。在运动前5分钟及运动后即刻分别采集静脉血测定各种激素含量。主要结果如下:受试者从事6×50m最大速度间歇游泳后,卵泡期各种激素浓度的变化均显著高于运动前安静状态,黄体期变化不一,FSH、LH降低,E_2、P、T及Ins升高。从事1000m全速游泳后,激素变化表现为卵泡期FSH、LH、E_2、P均升高,T及Ins降低;黄体期E_2、P、T升高,Ins降低,FSH、LH无显著变化,两期相比黄体期运动成绩优于卵泡期。上述结果提示:①受试者月经周期的黄体期机体有氧能力强于卵泡期,运动能力的增强与黄体期E_2、P、T水平升高有关。②FSH、LH与E_2、P分泌变化并非同步一致,说明运动中E_2升高并非受制于促性腺激素,而主要是卵巢分泌量升高所致。③运动中E_2、P、T具有协同效应,可抵抗疲劳,提高人体运动能力。