Blunted renal dopaminergic system activity in puromycin aminonucleoside-induced nephrotic syndrome.

BACKGROUND: A primary tubular sodium handling abnormality has been implicated in the edema formation of nephrotic syndrome. Dopamine synthesized by renal proximal tubules behaves as an endogenous natriuretic hormone by activating D(1)-like receptors as a paracrine/autocrine substance. METHODS: We examined the time courses of the urinary excretion of sodium, protein and dopamine in puromycin aminonucleoside (PAN)-treated and control rats. The rats were sacrificed during greatest sodium retention (day 7) as well as during negative sodium balance (day 14) for the evaluation of renal aromatic l-amino acid decarboxylase (AADC) activity, the enzyme responsible for the synthesis of renal dopamine. Also, the influence of volume expansion (VE) and the effects of the D(1)-like agonist fenoldopam (10 microg/kg bw/min) on natriuresis and on proximal tubular Na(+),K(+)-ATPase activity were examined on day 7. RESULTS: The daily urinary excretion of dopamine was decreased in PAN-treated rats, from day 5 and beyond. This was accompanied by a marked decrease in the renal AADC activity, on days 7 and 14. During VE, the fenoldopam-induced decrease in proximal tubular Na(+),K(+)-ATPase activity was more pronounced in PAN-treated rats than in controls. However, the urinary sodium excretion during fenoldopam infusion was markedly increased in control rats but was not altered in PAN-treated animals. CONCLUSION: PAN nephrosis is associated with a blunted renal dopaminergic system activity which may contribute to enhance the proximal tubular Na(+),K(+)-ATPase activity. However, the lack of renal dopamine appears not to be related with the overall renal sodium retention in a state of proteinuria.     

Digestive properties of the venom of the Australian Coastal Taipan, Oxyuranus scutellatus (Peters, 1867).

The digestive properties of Australian elapid snake venoms have not been studied to any great extent. To address this, the in vitro digestive properties of Oxyuranus scutellatus (Australian Coastal Taipan) venom were investigated in a simulation of the in vivo conditions using the parameters reported for the stomach of snakes and representative prey for this species. The amount of soluble protein released was measured over time using a bicinchoninic acid (BCA) assay. Dismembered mouse hindlegs were injected intramuscularly with 0.1 ml O. scutellatus venom (concentration 10 mg/ml) and maintained in a micro-anaerobic, acidic environment (pH approximately 1.2-1.7) at 25 degrees C. The bathing liquid was sampled every 24 h for 7 days, and assayed for soluble protein. Statistical analysis revealed that O. scutellatus venom increased the rate at which proteins were released when compared to a negative control suggesting the potential importance of envenomation in the digestion of whole prey.     

非胰岛素依赖型糖尿病患者血清唾液酸的改变

测定20例NIDDM伴有心脑血管病变的患者、20例单纯NIDDM患者的血清唾液酸（SA）水平，并与20例正常人进行比较。结果发现所有NIDDM患者的血清SA水平均显著增高（P＜0．01），其中伴有心脑血管疾病患者的血清SA水平显著高于单纯NIDDM患者（P＜0．05），同时血清SA水平与血清胰岛素及C肽水平、收好压之间存在相关。提示血清SA水平与NIDDM患者的心脑血管疾病关系密切，可能是心脑血管并发症发生的一个危险因素。     

过氧钒烟酸对糖尿病鼠苯丙氨酸羟化酶活性的影响

目的　探讨过氧钒烟酸（ Ｐ Ｏ Ｖ） 的降血糖作用的分子生物学机制。方法　选用 Ｓ Ｄ 大鼠用链脲佐菌素诱导产生糖尿病鼠动物模型，观察用 Ｐ Ｏ Ｖ 和美迪康（ Ｍｅｔ） 治疗后各组大鼠血、尿糖水平及血肝细胞质中苯丙氨酸羟化酶（ Ｐ Ａ Ｈ） 活性改变情况，并进行比较。结果　糖尿病鼠 Ｐ Ａ Ｈ 活性明显增高，用 Ｐ Ｏ Ｖ治疗４ 周后活性受到抑制，血糖水平明显下降，临床症状得以改善。结论　 Ｐ Ｏ Ｖ 的降糖作用优于美迪康，且未见明显毒副作用。     

孕妇血清与初乳中分泌型IgA含量的关系

目的探讨孕妇营养与初乳中分泌型免疫球蛋白Ａ（ＳＩｇＡ）含量的关系。方法对１０１例孕妇作了膳食营养评价，并对其血液营养学指标与产后第３ｄ初乳ＳＩｇＡ含量进行相关分析。结果孕妇血清ＩｇＡ与初乳ＳＩｇＡ呈明显的正相关（ｒ＝０．４９８Ｐ＜０．０１）；血清甘油三酯与初乳ＳＩｇＡ呈明显的负相关（ｒ＝－０．３３８Ｐ＜０．００５）；血清叶酸与初乳ＳＩｇＡ呈明显正相关（孕中期ｒ＝０．７３７Ｐ＜０．００１，孕晚期ｒ＝０．３６２Ｐ＜０．０１）相关呈高度显著性。结论初乳ＳＩｇＡ与孕妇个体免疫状态以及孕期代谢状态有关。     

2,3-Butanedione monoxime protects mice against the convulsant effect of picrotoxin by facilitating GABA-activated currents

While adult mice receiving picrotoxin (PTX) alone responded with clonic and tonic-clonic seizures, this response was greatly suppressed for mice simultaneously injected with 2,3-butanedione monoxime (BDM). For example, 60% and 10% of the mice convulsed when injected (i.p.) with 3.0 mg/kg PTX alone or PTX plus 205 mg/kg of BDM, respectively. In contrast, a non-oxime analogue of BDM, 2,3-butanedione (BTD), did not have this anticonvulsant effect. In order to explore the basis for the anticonvulsant effect of BDM, we recorded GABA-activated currents (I_GABA) of frontal cortical as well as ventromedial hypothalamic neurons before, during and after exposure to this oxime. BDM had a biphasic effect on concentrations (100 μM-40 mM) decreased and lower concentrations (0.01 μM–0.001 μM) potentiatedI_GABA; these effects of BDM reversed upon washout of the oxime. In contrast, BTD had no effect onI_GABA. Finally, when 0.001 μM BDM, 10–30 μM PTX and GABA were co-applied the inhibitory effect of the toxin onI_GABA was markedly suppressed. These data suggest that the anticonvulsant effect of oximes involves facilitation of the inhibitory action of GABA.     

两种鼠蚤成熟过程中组织化学研究Ⅰ糖原和PAS物质

目的：探讨不等单蚤Monopsyllns anisus(Rothchild）和级慢细蚤Leptopsylla segnis(Schoenherr）吸血消化成熟过程中糖原和PAS物质的变化。方法：用高碘酸－希夫反应（Periodic acid-Schiff reaction PAS)法显示未吸血蚤、吸血后不同消化时间蚤体内糖原和PAS物质。结果：2种蚤糖原和PAS物质以脂肪体含量最高。吸血后成蚤消化道各部分PAS反应均有增高，不同消化时间（24、48、72h）不存在显著差异。2种蚤中雌蚤吸血后卵黄细胞发育过程中PAS反应的变化相似，但不等单蚤发育较缓慢细蚤迟缓。结论：吸血将导致2种蚤消化道糖原不同程度的增加。亦能促进雌蚤卵黄细胞的发育。     

Effect of distension on adrenergic innervation of the rat urinary bladder

Summary The effect of distension on adrenergic innervation was investigated in the rat urinary bladder. Bladders were distended for 3 h by forced diuresis and ballon obstruction, and specimens were taken from the bladder dome, body and neck for the demonstration of glyoxylic acid-induced fluorescence of catecholamines. Depletion of catecholamines started after 10 h and was almost complete after 2 days. The fluorescence had recovered part way after 5–7 days and was practically normal after 21 days. Small, intensely fluorescent (SIF) cells in the ganglia continued to leak catecholamines throughout the 21-day study period. The primary clinical success of distension therapy for the treatment of unstable bladder may be at least partly due to a reversible disturbance in the function of the adrenergic nerves, which have an excitatory alpha-adrenergic dominance in such cases, but the persistent leakage from SIF cells raises the question of whether distension causes prolonged disturbances in bladder function.     

New peritoneal dialysis solutions

Summary: Current peritoneal dialysis solutions are not biocompatible, particularly in respect to low pH, high osmolality and use of lactate. In addition, glucose is not an ideal osmotic agent. Recent advances in the formulation of peritoneal dialysis fluids aim to provide a more physiological environment to preserve membrane integrity. the effects of pH and lactate have been overcome by the use of bicarbonate based solutions whilst icodextrin (glucose polymers) often prolonged ultrafiltration in spite of being isomotic to uraemic plasma. Future formulations will see a combination of osmotic agents (including amino acids) and bicarbonate to achieve a more biocompatible solution whilst still meeting the ultrafiltration needs of the patients. Additives (glycosaminoglycans, procysteine) may protect the peritoneum from free radical injury.     

1-乙基-6-氟-1,4-二氢-4-氧代-7-(4-芳酰硫代氨甲酰基-1-哌嗪基)-3-喹啉羧酸的合成及抗菌作用

Thirteen new 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(4-aroyl-thiocarbamoyl- 1 piperazinyl)-3-quinoline carboxylic acids were prepared, Their structures were characterized by elemental analysis, IR, HNMR and MS spectra.Preliminary pharmacological tests indicated that some of compounds Ia～m possess strong inhibiting activity against Escherichia coli, Bacillus subtilis and Proteus at concentration of 100 μg/ml.