Single-dose pharmacokinetics of paracetamol and its conjugates in Chinese non-insulin-dependent diabetic patients with renal impairment

Objective: A single oral dose of paracetamol (20 mg · kg⁻¹) was given to 38 Chinese patients with non-insulin-dependent diabetes mellitus (NIDDM) who had either normal renal function or varying degrees of renal impairment, with creatinine clearances ranging from 4 to 123 ml · min⁻¹ · 1.73 m⁻². The plasma and urinary concentrations of paracetamol and its major metabolites were measured by high-performance liquid chromatography (HPLC). Results: The absorption and elimination of paracetamol were unaffected by renal impairment. However, the area under the plasma concentration time curve and the elimination half-life of paracetamol metabolites increased significantly with worsening renal insufficiency. Mean renal clearances of paracetamol and its conjugates were significantly reduced in these subjects. There was no evidence of altered metabolic activation with renal impairment. Conclusion: The results demonstrate that paracetamol disposition is minimally affected by diabetic nephropathy; however, extensive accumulation of conjugates may occur. Received: 2 September 1996 / Accepted in revised form: 11 December 1996     

Renal acid excretion in early infancy

In early infancy, complex disorders of acid base metabolism are more frequent than in any other age group, with a predisposition to metabolic acidosis due to an age-related low renal capacity for acid excretion and an unphysiologically high actual renal acid load in nutrition with common formulas. Recently in preterm and small-for-gestational-age infants, persistent maximum renal net acid excretion (NAE) with subnormal or normal blood acid base status, impaired weight gain, and adaptive hormonal reactions have been observed. Incipient late metabolic acidosis is one example of a mixed disorder of acid base metabolism with maximum renal NAE in early infancy. Alkali therapy is highly effective and can be realized both on an individual basis, using urine pH screening as a diagnostic criterium for maximum renal acid stimulation, or on a general preventive level using modified standard formula with a reduced actual renal NAE similar to that seen on alimentation with human milk. From an integrated point of view, the low glomerular filtration rate and renal capacity for acid excretion beyond the developmental age of more than 44 weeks, may well be interpreted as the result of a specific adaptation to breast feeding sparing energy, and thus an evolutionary advantage for the survival of mother and child. Received July 10, 1996; received in revised form and accepted October 7, 1996     

肾综合征出血热病毒气溶胶的物理稳定性实验研究

本文采用荧光素钠正常鼠脑悬液做模拟示踪物质，对肾综合征出血热病毒气溶胶在空气中的物理稳定性进行了测定，并与其生物稳定性做了比较。结果表明：病毒气溶胶的粒子大小在１ｕｍ左右，它随气溶胶的胶龄增长而减少，且其分散度变窄。初始气溶胶的物理回收率及其各胶龄的物理存留率均明显地高于它的生物回收率和生物存活率。本文还就肾综合征出血热病毒气溶胶的物理稳定性和生物稳定性，对本病空气传播的影响进行了讨论。     

Modulation of bone loss during calcium insufficiency by controlled dynamic loading

Summary Changes in the midshaft cross-sectional area of the ulna were measured in egg-laying turkeys on a diet insufficient in calcium. Left: right comparisons were used to assess the bone loss over a six-week period due to 1) calcium insufficiency, 2) calcium insufficiency plus disuse, and 3) calcium insufficiency and disuse interrupted by a short daily period of intermittent loading applied from an external device. Calcium insufficiency alone in the intact ulna resulted in a 15% reduction in cross-sectional area. In the functionally deprived bones this loss was increased to 32%. In bones where the disuse was interrupted by a single short daily period of loading, the degree of bone loss was significantly modified (P<0.006) to 25%. No significant difference in the modulating effect of loading was achieved by varying the peak strain from 0.0015 to 0.003, the strain rate from 0.01 to 0.05, or the duration of the single loading period from 100 sec per day to 25 minutes. All the loading regimes employed had been demonstrated to be osteogenic in mature male birds on a diet sufficient in calcium.     

Recurrence of nephrocalcinosis after renal transplantation in an adult patient with primary hyperoxaluria type I

The medical history of a 42-year-old patient with primary hyperoxaluria type I is presented. Primary hyperoxaluria was suspected after renal transplantation, when oxalate deposits were found in a biopsy of the kidney graft. Diagnosis of type I hyperoxaluria was confirmed by the finding that significantly increased amounts of glycolic acid and oxalic acid were excreted. Treatment of the patient with 500 mg pyridoxine daily resulted in a decrease of the excretion of oxalate to normal values.     

Twenty-four-hour ambulatory blood pressure profiles in pediatric patients after renal transplantation

Ambulatory blood pressure monitoring was applied in 27 pediatric patients aged 6.3 – 24.3 (median 15.0) years who had been transplanted 1.5 – 8.4 years previously. Daytime values were compared with the mean of 10 concomitant casual blood pressure recordings. At the time of the study, antihypertensive drugs were given to 17 patients. Inulin clearance ranged from 18 to 116 (median 66) ml/min per 1.73 m². Ambulatory blood pressure monitoring confirmed hypertension or normotension determined by casual blood pressure measurements in 63% of patients. The physiological nocturnal dip in blood pressure was attenuated or reversed in 8 of 27 patients. It was reduced in all 3 patients with renal artery stenosis of the graft, in 3 of 4 patients with chronic rejection, in the only patient with recurrent focal segmental glomerulosclerosis, and in 1 of 6 patients with past acute rejection. The dipping was not related to inulin clearance. In conclusion, casual blood pressure measurements do not accurately reflect blood pressure in pediatric patients transplanted more than 1.5 years previously. A reduced nocturnal dip in blood pressure may indicate an underlying renovascular or renoparenchymal pathology. Ambulatory blood pressure monitoring should regularly be applied in patients with renal transplants. Received May 23, 1995; received in revised form June 18, 1996; accepted June 20, 1996     

下肢静脉高压症顺行性静脉造影的诊断意义

本文对临床上有下肢静脉高压症的56例病人,共76条下肢,进行了顺行性静脉造影的X线研究。其中对12条下肢做了经皮腘静脉造影检查。作者认为:(1)下肢静脉高压除因下肢静脉血栓形成外,下肢深静脉瓣膜功能不全是其另一个主要原因。(2)经皮腘静脉造影是检测下肢深静脉瓣膜功能的有效、准确的方法。(3)下肢静脉造影的联合应用,在检查下肢静脉高压中具有科学性和准确性。     

细胞粘附分子在恶性肾肿瘤中的表达

采用斑点杂交和Ｎｏｒｔｈｅｒｎ杂交技术研究１２例恶性肾肿瘤组织中细胞间粘附分子和血管细胞粘附分子基因转录水平的表达。结果发现，细胞间粘附分子的阳性表达率为１００％，血管细胞粘附分子的阳性表达率为７５％（９／１２）。提示恶性肾肿瘤细胞中存在活化的细胞间粘附分子和血管细胞粘附分子基因，并可能影响肿瘤与宿主间的免疫反应。