Prediction of post‐operative glomerular filtration rate after nephrectomy for renal malignancy

The importance of a correct estimation of contralateral renal function in cases of renal malignancy is obvious, necessitating a conservative approach to tumour resection when function of the contralateral kidney is markedly reduced. The aim of the present study was to determine the accuracy of preoperative gamma camera renography and ⁵¹Cr‐EDTA clearance to predict the glomerular filtration rate (GFR) early and up to 6 months after nephrectomy for renal malignancy. Patients (n=40) underwent both gamma camera renography (^99mTC‐DTPA) and ⁵¹Cr‐EDTA clearance preoperatively, whereas ⁵¹Cr‐EDTA clearance was measured within 1 week and up to 6 months after nephrectomy. The single kidney GFR values of the contralateral kidneys were estimated preoperatively and then compared with the post‐operative ⁵¹Cr‐EDTA clearance values. The predicted GFR values were lower compared with the measured post‐operative ⁵¹Cr‐EDTA clearance values (45 ± 2 vs. 54 ± 3 ml min^–1 1 week after nephrectomy and 53 ± 3 ml min^–1 6 months later, P<0·01, respectively). The difference between the measured and predicted GFR was larger in patients below the median age of 60 years (P<0·05) and confined to patients with a relative uptake of >30% by the tumour affected kidney. Prediction of post‐operative GFR by non‐invasive renal function tests performed prior to surgery for renal malignancy underestimate post‐operative GFR when the function of the tumour affected kidney is preserved, indicating an adaptive GFR increase in these cases.     

肾动态显像前位采集测定肾脏前移患者肾小球滤过率的可行性

目的探讨单侧肾脏前移患者肾动态显像前位采集测定肾小球滤过率(glomerular filtration rate,GFR)的可行性和准确性。方法选择2017年8月至2021年12月于复旦大学附属中山医院核医学科行肾动态显像，并通过Gates法测定GFR的单侧肾脏前移患者22例，同时进行前位和后位图像采集，并使用后位图像处理双肾数据，使用前位图像处理前移单肾数据，计算相应GFR值。健侧肾后位采集测定的GFR值与前移肾前位采集测定的GFR值之和记作GFR_优化；常规后位采集测定的双肾GFR值之和记作GFR_常规。采用慢性肾脏病流行病学协作组(Chronic Kidney Disease Epidemiology Collaboration,CKD-EPI)推荐的基于血清肌酐(serum creatinine,sCr)方程计算的估算GFR(estimated GFR,eGFR)作为参照值，比较GFR_优化、GFR_常规与eGFR的差异，并进行Pearson相关性分析。结果22例患者前移单肾的前位肾脏深度显著小于后...     

Influence of blood components on the tissue uptake indices of cyclosporin in rats

The effect of blood components on the transfer of cyclosporin into brain, salivary gland, liver and kidney was measured in rats by an an vivo double isotope, tissue-sampling single injection technique. The brain-, salivary gland- and liver extraction of [3H] cyclosporine relative to [14C]butanol were studied with an intracarotid and a portal vein injection technique; the kidney extraction of [3H]cyclosporin relative to p[14C]aminohippuric acid was measured after a rapid injection in the aorta. The injection vehicles were a Ringer's solution [Ringer-4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid], rat plasma, human plasma, human red blood cells (RBC) suspension and human blood. The brain extraction (1-4%), the salivary extraction (25-74%) and the kidney extraction (8-47%) varied markedly depending on which blood components were added to the injection solution. The effect of RBC binding on tissue extraction was by far more pronounced than that of plasma protein binding. The binding of cyclosporin to RBC retards particularly the uptake of this drug by kidney. Moreover the kidney penetration of cyclosporin was confirmed by thaw-mount autoradiography after injection of the labeled drug in the aorta; the micrographs showed that the renal clearance of cyclosporin was restricted largely to the glomerular route. In contrast the hepatic extraction of [3H]cyclosporin was high (48-84%) and generally nonlimited by its binding to blood components; this could explain the high concentrations of drug observed in this tissue. In summary, cyclosporin binding to RBC and plasma proteins reduces drug uptake by brain, kidney and salivary gland, but causes little inhibition of hepatic uptake of cyclosporin.     

Cyclooxygenase products and atrial natriuretic peptide modulate renal response to endothelin

The effects of porcine endothelin on renal function were investigated in the isolated perfused rat kidney. After control clearance periods, endothelin (80, 120 or 320 pmol) or vehicle was added to the perfusate, and four 10-min experiments followed. Endothelin markedly reduced renal perfusate flow (RPF) as a result of its potent renal vasoconstrictor effect. At the highest but not low doses of endothelin, glomerular filtration rate (GFR) fell disproportionately to the reduction in RPF. Fractional Na excretion was also increased after kidney exposure to endothelin, suggesting an inhibition of tubular Na reabsorption by the peptide. Perfusion with low [Ca] severely blunted the hemodynamic effects of endothelin. Pharmacological blocking of renal cyclooxygenase by indomethacin or ibuprofen caused a further decline in RPF, GFR and absolute but not fractional Na excretion in kidneys challenged with endothelin. Atrial natriuretic peptide increased GFR and filtration fraction (FF), but not RPF, in kidneys previously exposed to 120 pmol endothelin. This was associated with a dramatic diuretic and natriuretic effect. The results demonstrate that 1) endothelin acts directly on the kidney, eliciting hemodynamic, diuretic and natriuretic responses that are dependent on the dose used and partially on the availability of extracellular Ca, 2) the renal effects of endothelin are exacerbated by cyclooxygenase blocking, suggesting that the vasoconstrictor effect of the peptide may be modulated by vasodilatory prostaglandins, and 3) atrial natriuretic peptide counteracts the renal function deterioration induced by endothelin, raising the possibility of an interplay between these vasoactive hormones in the control of renal function.     

超声内镜对胃癌术前分期的临床意义

目的探讨超声内镜对胃癌术前分期的意义。方法对69例胃癌患者进行术前内镜超声检查,并与术后组织病理分期比较。结果在判断胃癌浸润深度T分期上,EUS总的正确率36.2%,其中T1m41.7%,T1sm75%,T2mp100%,T3se66.7%,T4si25%;在判断淋巴结转移N分期上,EUS总的正确率62.3%,其中N-100%,N+53.8%。结论EUS对胃癌术前T及N分期具有重要意义,但是如何避免分期过深或过浅、如何鉴别良恶性淋巴结方面,尚需进一步探讨。     

Effect of renovascular hypertension on experimental glomerulonephritis in rats.

Systemic hypertension is a major risk factor that determines the rate of progression of kidney disease. The underlying mechanisms, however, are incompletely understood. To gain insight into these mechanisms, the present study was undertaken to characterize the effects of renovascular hypertension on the course of anti-thymocyte antibody-induced glomerulonephritis. Glomerulonephritis was induced in rats 6 weeks after the initiation of two-kidney, one-clip hypertension, when blood pressure was already increased. Structure and function of the clipped and the nonclipped kidney were examined 5 days later. Glomerular filtration rate (GFR) was measured by inulin clearance. The induction of nephritis did not alter the blood pressure in either hypertensive rats or normotensive controls. Albuminuria increased slightly in normotensive rats after the induction of nephritis, whereas no significant differences were found between hypertensive rats with or without nephritis. No significant differences were found for the GFR values of normotensive controls and nephritic animals or for values in the clipped kidney with or without nephritis. However, the GFR of the nonclipped kidney was significantly reduced in nephritic animals as compared with all other groups. Morphologic evaluation revealed that hypertensive rats with nephritis exhibited a combination of characteristics of nephritis and hypertensive glomerular injury. Histologic findings of nephritis, such as glomerular binding of rabbit IgG and glomerular proliferation and mesangial matrix expansion, were similar after the induction of nephritis in controls and in the clipped and nonclipped kidneys of hypertensive animals. However, intraglomerular microaneurysms were significantly more often found in the non-clipped kidneys after the induction of nephritis. Hypertension-induced deterioration of glomerular function was not associated with marked morphologic deterioration but rather with a combination of the characteristics of nephritis and hypertensive glomerular injury.     

Evidence for luminal uptake of gentamicin in the perfused rat kidney.

Gentamicin nephrotoxicity is preceded by proximal tubular accumulation of the drug. To determine whether gentamicin enters cells from the peritubular surface or from the tubular lumen after filtration, we studied filtering and non-filtering isolated perfused rat kidneys. Filtering kidneys were perfused with 6 g/dl of albumin, non-filtering kidneys with 11 g/dl of albumin and a lower perfusion pressure after ureteral occlusion. Accumulation of [14C]gentamicin in filtering or non-filtering kidneys was compared to that of [14C]cephaloridine, which is taken up primarily at the antiluminal cell surface. Renal accumulation of gentamicin was approximately 4 times greater in filtering than in non-filtering kidneys after 1 hr of perfusion. In contrast, accumulation of [14C]cephaloridine was 38% greater in the non-filtering model. Gentamicin did not significantly change sodium reabsorption or glomerular filtration rate during the 60-min study. Fractional potassium excretion, however, was slightly but significantly increased by perfusion with gentamicin. Our results indicate that 1) renal tubular gentamicin uptake is primarily by filtration and subsequent reabsorption and 2) the non-filtering and filtering isolated perfused rat kidney may be used to investigate mechanisms of renal accumulation of other nephrotoxic agents.     

The effect of simvastatin on erythrocyte membrane fluidity during oxidative stress induced by cardiopulmonary bypass: a randomized controlled study

BACKGROUND: Abnormal erythrocyte deformability can cause severe complications during cardiopulmonary bypass (CPB) surgery, including both hemolysis and perfusion abnormalities. OBJECTIVES: The goals of this study were to evaluate changes in erythrocyte membrane fluidity and lipid peroxidation during CPB and to examine the effect of simvastatin treatment on these parameters. METHODS: Patients undergoing cardiac surgery involving CPB were selected and randomized to receive either simvastatin 40 mg/d or placebo for 3 weeks before surgery. Three blood samples were obtained at different times during surgery for analysis of erythrocyte membrane fluidity, anion permeability, and lipid peroxidation. Erythrocyte ghosts were prepared and incubated with a lipophilic fluorescent probe (diphenyl-hexatriene), and fluorescence anisotropy was evaluated by spectrophotofluorimetric assay as a measure of membrane fluidity. Anion permeability was evaluated by the specific absorption of methemoglobin (CM) at 590 and 635 nm after treatment of heparinized blood with NaNO2. The formation of thiobarbituric acid-reactive substances was evaluated as an index of lipid peroxidation. Aspartate transaminase and lactate dehydrogenase were also measured as indices of hemolysis. RESULTS: Forty patients met the inclusion criteria (20 simvastatin, 20 placebo). Their characteristics differed significantly at baseline only in terms of the lipid profile; the statin group had higher levels of high-density lipoprotein cholesterol (P = 0.01) and lower levels of low-density lipoprotein cholesterol (P = 0.001) than the placebo group. CPB was found to significantly modify characteristics of the erythrocyte membrane. Compared with preoperative values, CPB induced decreases in both mean (SD) erythrocyte membrane fluidity and anion permeability (preoperative CM: 0.69 [0.02]; 24-hour postoperative CM: 0.18 [0.02]; P < 0.001) and an increase in mean (SD) membrane lipid peroxidation (preoperative malonyl dialdehyde [MDA]: 0.21 [0.01] nmol/mL; postoperative MDA: 0.10 [0.02] nmol/mL; P < 0.001). Treatment with simvastatin was associated with a significant reduction in mean (SD) membrane lipid peroxidation both preoperatively and at 24 hours postoperatively compared with placebo (preoperative MDA: 0.07 [0.01] vs 0.10 [0.02] nmol/mL, respectively; P < 0.05; postoperative MDA: 0.10 [0.04] vs 0.21 [0.01] nmol/mL; P < 0.05). In addition, statin treatment was associated with significant increases in anion permeability preoperatively and postoperatively compared with placebo (preoperative CM: 0.79 [0.01] vs 0.69 [0.02]; P < 0.01; 24-hour postoperative CM: 0.30 [0.01] vs 0.18 [0.02]; P < 0.01). CONCLUSION: The results of this study suggest that among these patients undergoing CPB surgery, use of simvastatin for 3 weeks before the surgery had significant beneficial effects on erythrocyte membrane fluidity, lipid peroxidation, and anion permeability.     

Selective transport of an anti-transferrin receptor antibody through the blood-brain barrier in vivo

The brain capillary endothelium, which makes up the blood-brain barrier (BBB) in vivo, expresses high concentrations of transferrin receptor, and recent studies show that an antitransferrin receptor monoclonal antibody may function as a BBB drug transport vector. The present report examines the pharmacokinetics of clearance of radiolabeled antitransferrin receptor monoclonal antibody from the bloodstream in rats in vivo, and also assesses the extent to which brain selectively extracts the antibody from the blood compared to other peripheral organs such as liver, kidney, myocardium, or lung. [125I]Mouse immunoglobulin G2a control antibody was cleared monoexponentially with a half-time of 9.8 +/- 2.3 h. The clearance of the [3H]OX-26 antitransferrin receptor antibody from blood was biexponential with half-times of 2.2 +/- 0.8 min (61 +/- 10% of clearance) and 3.9 +/- 0.2 h (39 +/- 4% of clearance). The OX-26 antibody was rapidly taken up by liver during the first 60 min after injection, but this uptake reached rapid saturation, and hepatic OX-26 content actually declined subsequent to the first hour after injection. In contrast, brain continuously extracted the OX-26 antibody from the bloodstream, and the brain volume of distribution of OX-26 reached a value 18-fold greater than the volume of distribution of the mouse immunoglobulin G2a at 5 h after injection. There was no specific uptake of the OX-26 by myocardium or lung, and minor uptake by kidney was observed that also reached saturation within the first 60 min after injection.(ABSTRACT TRUNCATED AT 250 WORDS)     

Protective effect of intrarenal calcium membrane blockers before or after renal ischemia. Functional, morphological, and mitochondrial studies

The present study examined whether a pre- or postischemic infusion of verapamil (V) or a postischemic infusion of nifedipine (N), drugs which block calcium (Ca++) influx across plasma membranes, provides protection against ischemic acute renal failure (ARF) in dogs. Renal hemodynamics and excretory function were examined 1 h (initiation phase) and 24 h (maintenance phase) after a 40-min intrarenal infusion of norepinephrine (NE). In each case, the uninfused contralateral kidney served as control. Four groups were studied: (a) dogs receiving NE alone; (b) dogs receiving an intrarenal infusion of V for 30 min before NE (V + NE); (c) dogs in which intrarenal V was infused for 2 h, beginning immediately after completion of NE infusion (NE + V); and (d) dogs in which intrarenal N was infused for 2 h, beginning immediately after completion of NE infusion (NE + N). Glomerular filtration rate (GFR) in the NE kidneys, as assessed by inulin clearance, at 1 and 24 h averaged 2.4 +/- 1.1 and 5.0 +/- 2.0 ml/min, respectively, as compared with control kidney GFRs of 28.0 +/- 3.5 and 43.8 +/- 5.0 ml/min, respectively (both at least P less than 0.01). In the V + NE group, GFR at 1 and 24 h averaged 15.0 +/- 5.5 and 31.0 +/- 4.5 ml/min, respectively, both at least P less than 0.05 as compared with values from NE kidneys. GFRs in the NE + V group averaged 15.0 +/- 2.4 and 16.3 +/- 3.6 ml/min at 1 and 24 h, both at least P less than 0.02 as compared with values from NE kidneys. GFR in the NE + N group averaged 18.6 +/- 6.0 ml/min at 24 h (P less than 0.05 as compared with GFRs in the NE kidneys). In addition, function of cortical mitochondria (Mito) was examined at the end of the 40-min NE infusion and after 1 and 24 h of reperfusion in the NE alone and NE + V groups. Mito respiration, assessed by acceptor control ratios, was reduced at each period in the NE alone kidneys. After 24 h, these Mito had accumulated Ca++ and exhibited reduced Ca++ uptake and increased Ca++ release rates. Mito from NE + V kidneys respired normally, did not accumulate Ca++, and exhibited no alterations in Ca++ uptake or release. Light and electron microscopy also demonstrated morphological protection of V against tubular necrosis and cell injury. Mito from the NE + N kidneys also respired normally and did not accumulate significant amounts of Ca++. The results of the present studies therefore demonstrated that chemically dissimilar calcium entry blockers exert substantial functional, cellular, and morphological protection against experimental ischemic ARF. These findings are compatible with the hypothesis that increased cytosolic Ca++ is critically important in the maintenance of renal vasoconstriction and the development of cellular necrosis with subsequent tubular obstruction in NE-induced ischemic ARF. V or N may provide protection against renal injury by retarding any increase in cytosolic Ca++ in renal vasculature and epithelium.     

Stability, protein binding and clearance studies of [99mTc]DTPA. Evaluation of a commercially available dry-kit

[99mTc]DTPA has achieved widespread use for the measurement of glomerular filtration rate (GFR) with the single injection plasma clearance technique and for gamma-camera renography. However, the quality of the commercial preparations varies. The purpose of the present investigation was to study the quality of a commercial [99mTc]DTPA preparation (C.I.S., France) with reference to stability, protein binding and accuracy of the determined plasma clearance values as a measure of GFR. The stability of the preparations was studied by thin-layer chromatography, the in vitro protein binding by Sephadex filtration after incubation with human serum albumin and in vivo protein binding by filtration of human plasma. The accuracy of the plasma clearance values was investigated by comparison with the simultaneously measured plasma clearance of [51Cr]EDTA. There was no detectable free pertechnetate or hydrolysed reduced technetium in eight vials five and six hours after the preparation. The in vitro protein binding 10 (20), 120 and 300 min after the preparation of eight vials was 2.3% (0.8%), 0.2% and 0.1%, respectively. The in vivo protein binding in 12 patients 5, 90 and 180 min after the injection was 0.3%, 0.7% and 1.1%, respectively. The plasma clearance of [99mTc]DTPA was on an average 3.7% higher than that of [51Cr]EDTA in 27 patients. It is concluded that the [99mTc]DTPA preparation is reliable for the measurement of GFR. The preparation is stable for at least six hours at room temperature. It is recommended not to use the [99mTc]DTPA until 30 min after the preparation.     

比较不同测量肾脏深度方法及其对肾动态显像评估肾小球滤过率的影响

目的 对比采用CT、SPECT/CT侧位相、Tonnesen公式及Taylor公式4种方法得出的肾脏深度的差异，观察其对肾动态显像评估分肾肾小球滤过率（GFR）的影响。方法 连续收集84例同时接受放射性核素肾动态显像及腹部CT检查患者，采用CT、SPECT/CT侧位像、Tonnesen公式及Taylor公式测量双侧肾脏深度，并将之代入Gates法，获得校正后的分肾GFR。以CT测定值为肾脏标准深度，分析其他3种方法所测双肾深度的差异及其对分肾GFR测定值的影响。结果 SPECT/CT侧位像、Tonnesen公式和Taylor公式与CT所测双肾深度差异均有统计学意义（P均<0.001）。SPECT/CT侧位像与CT测值的差值与肾脏标准深度无相关（P均>0.05），而Tonnesen公式和Taylor公式测值与CT测值的差值均与肾脏标准深度呈中度相关（右肾r_Tonnesen=0.781，左肾r_Tonnesen=0.804；右肾r_Taylor=0.639，左肾r_Taylor=0.613，P均<0.01）。以4种方法得到的分肾GFR之间差异有统计学意义（P<0.001）。结论 以CT测定肾脏深度为标准，在肾动态显像中以不同方法校正双侧肾脏深度，有助于提高测量肾脏深度以及测算GFR的准确性。通过SPECT/CT侧位显像测量肾脏深度更具临床价值。     

Renal haemodynamic changes in response to moderate hyperglycaemia in type 1 (insulin-dependent) diabetes mellitus

The prevailing blood-glucose level has been found to influence renal haemodynamics in type 1 (insulin-dependent) diabetes mellitus. In a group of 48 type 1 diabetic patients with normal serum creatinine (less than 120 mumol l-1) and without persistent proteinuria, no relationship was present between blood glucose, corrected to near normoglycaemia (6.8 [6.2 to 7.3] mmol l-1 (median [95% confidence interval]), and glomerular filtration rate (GFR), effective renal plasma flow (ERPF) determined with 125I-iothalamate and 131I-hippuran respectively. GFR tended to increase (2 [-1 to +4] ml min-1 1.73 m-2, 0.05 less than P less than 0.10) and ERPF did not change after a blood glucose rise of 7.9 (7.0 to 8.9) mmol l-1, achieved by an intravenous glucose load in 31 patients. The individual changes in GFR and ERPF were correlated (r = 0.60, P less than 0.005). The changes in GFR were inversely related to baseline blood glucose (r = -0.45, P less than 0.02), but not to baseline GFR. GFR increased (3.5 [0 to +12] ml min-1 1.73 m-2, P less than 0.01) if baseline blood glucose was less than or equal to 6.8 mmol l-1 (n = 16) but ERPF did not. Achievement of near normoglycaemia before measurement of kidney function in type 1 diabetes appears to reduce the influence of variation in glycaemia on renal haemodynamics and thus would improve comparison between and within individuals. Moderate hyperglycaemia can cause a small rise in the glomerular filtration rate.     

Functional adaptation of nephrons in dogs with acute progressing to chronic experimental glomerulonephritis.

Although a diminished fractional excretion of sodium (FENa) is the hallmark of acute proliferative glomerulonephritis (APGN), an enhanced natriuresis per glomerular filtration rate (GFR) in the chronic phases of this disease has been reported. We studied this adaptive response utilizing two different split-bladder dog models with unilateral, and a third group of dogs with bilateral Masugi's nephritis. Group I. Six dogs with unilateral nonaccelerated APGN studied a mean of 6 days after induction had a mean base-line APGN/intact kidney GFR of 31/50 ml/min (P less than 0.005) and FENa of 0.2/0.75% (P less than 0.005). Acute volume expansion caused a smaller absolute increase in FENa from the APGN kidney, 1.6%, than from the intact kidney, 4.0%, (P less than 0.01). Maximum tubular secretion of rho-aminohippuric acid/GFR (TmPAH/GFR) measured in three dogs was higher in the APGN kidney than intact kidney, 13.1 vs. 9.3 mg/dl. Subsequent studies on three of the six dogs when the disease had become chronic demonstrated a reversal in the pattern of sodium excretion in response to volume expansion. Group II. Six dogs with accelerated unilateral APGN (dogs presensitized to antibody source) studied a mean of 5 days after induction had a mean base-line APGN/intact kidney GFR of 16/57 ml/min and FENa of 0.22/0.12% (P less than 0.1). Contrary to group I, volume expansion caused a greater absolute increase in FENa from the APGN kidney, 5.8%, than from the intact kidney, 2.9% (P less than 0.05). TmPAH/GFR studied in four dogs was similar for both kidneys, 17.9 and 18.5 mg/dl for the APGN kidney and intact kidney, respectively. Group III. Sequential studies were performed on seven dogs with bilateral nonaccelerated APGN. Initially each demonstrated sodium retention and a smaller absolute increase in FENa in response to volume expansion compared to a predisease control study. With disease progression, volume expansion induced a greater absolute increase in FENa than in the control study. We concluded that (a) the fractional excretion of sodium from the APGN kidney will be less or greater than the contralateral intact kidney or control study depending on the severity and/or chronicity of the disease, possibly as the result of morphologic alterations; (b) the degree of extracellular fluid volume expansion is an important variable influencing similarity of glomerulotubular balance between the APGN and contralateral intact kidney; and (c) the "intact nephron hypothesis" applies in a limited fashion to kidneys with APGN in the absence of volume expansion just as it does for kidneys with chronic glomerulonephritis or pyelonephritis.     

Urinary excretion of epidermal growth factor in living human kidney donors and their recipients

Abstract. Epidermal growth factor (EGF) is a growth-promoting peptide that is synthesized in the distal tubules of the kidney and excreted in urine. EGF has been suggested to play a role in the repair after renal tissue damage, as well as in compensatory growth of the remaining kidney after uninephrectomy. The present study examined the urinary EGF excretion after uninephrectomy and transplantation among relatives. The urinary EGF excretion rate and the glomerular filtration rate (GFR) were followed for 26–54 days in 16 healthy kidney donors and nine recipients. After uninephrectomy the median urinary EGF excretion rate in the donors was not 50% of the pre-operative value, but around 65% (95% confidence limits of the median on the fifth post-operative day: 59–72%). This suggests that there is a compensatory increase in the EGF excretion rate from the remaining kidney of around 30% after uninephrectomy. A similar compensatory increase was demonstrated for GFR, indicating that the compensatory changes in EGF excretion rate and GFR might be correlated. In the transplanted kidneys, GFR was consistently around 15% lower and EGF excretion rate around 40% lower than in the corresponding kidneys remaining in the donors. This might reflect ischaemic and drug-induced damage of the transplanted kidneys. The present study demonstrated a compensatory increase of around 30% in urinary EGF excretion from the remaining kidney after uninephrectomy in healthy humans. Whether EGF plays a role in the adaptive processes in the remaining kidney or whether changes in EGF excretion are merely of a secondary nature is still uncertain.     

人工髋关节置换术下肢不等长的处理

【目的】研究人工髋关节置换术下肢不等长的处理方法。【方法】对89例接受单侧人工髋关节置换术患者的临床资料进行分析。术前通过临床及对骨盆前后位X线片的测量评估双下肢不等长的程度．然后采用术前模板预测股骨颈截骨平面和假体植入位置，同时术中标记和测量股骨近端至髋臼上方两标志点的间距，尔后在术前估计的位置进行股骨颈截骨。置入假体试模之后再次测量两标志之间的距离，最后通过调整股骨头假体颈部或头部长度进一步进行纠正。【结果】术前患肢短缩1．5～5cm的58例患者中．术后仅7例患肢短缩或延长1．5～2．0cm。术前双下肢等长的31例患者中．术后仅2例患侧延长超过1．0cm。【结论】通过术前测量评估，用模板预测股骨颈截骨水平，采用术中骨标志间距测量，置入假体试模后再次测量，调整股骨头假体颈部及头部长度等方法是预防和治疗人工髋关节置换术后下肢不等长的有效方法。     

Factors affecting early knee-flexion range of motion after total knee arthroplasty

[Purpose] To investigate the factors affecting the knee-flexion range of motion in the early period after total knee arthroplasty. [Participants and Methods] Ninety-nine patients who had undergone total knee arthroplasty at our hospital between 2016 and 2019 were allocated into two groups based on the presence of a 110° knee-flexion range of motion at 14 days post-surgery. From medical records, we extracted data for the participants’ basic attributes and preoperative/postoperative physical function (knee-flexion range of motion, Timed Up & Go Test results, resting/walking pain according to a numerical rating scale, and knee-extension muscle strength). Postoperative physical function was measured 14 days post-surgery. [Results] Preoperative knee-flexion range of motion, preoperative femorotibial angle, postoperative knee-extensor strength, and postoperative Timed Up & Go Test value differed significantly as factors related to achieving a 110° knee-flexion range of motion. Through further statistical analyses, we selected the preoperative knee-flexion range of motion, preoperative femorotibial angle, preoperative Timed Up & Go Test result, and postoperative knee-extension strength as factors affecting the knee-flexion range of motion at 14 days post-surgery. [Conclusion] Preoperative knee-flexion range of motion, preoperative femorotibial angle, preoperative Timed Up & Go Test result, and postoperative knee-extension strength influence knee-flexion range of motion at 14 days after total knee arthroplasty, and our findings indicate the effectiveness of active physiotherapy interventions.     

Renal functional reserve in pigs: renal haemodynamics,renal tubular function and salt and water homeostatic hormones during amino acid and dopamine stimulation

The purpose of the study was to evaluate renal functional reserve [RFR is the difference between glomerular filtration rate (GFR) at rest and maximal GFR after stimulation] in a controlled study in normal pigs. Our basic hypothesis was that a decreased RFR may be used as an early indicator of renal deterioration, i.e. a test to disclose significant obstruction as opposed to simple dilatation in hydronephrosis. During various forms of stimulation (amino acids, captopril and dopamine), we measured changes in GFR, renal plasma flow (RPF), tubular reabsorption of sodium and water, net uptake from plasma to the kidney of three salt and water homeostatic hormones (angiotensin II, aldosterone and atrial natriuretic peptide) and of glucagon, which is thought to play a key role as mediator of the GFR increase during amino acid infusion. We found the largest GFR increase during combined infusion of amino acids and dopamine (+13%), but compared with a non-stimulated control group, the GFR increase was statistically non-significant. RPF increased by 57% during stimulation with amino acids plus dopamine (P<0·001), while tubular reabsorption of sodium and water, and renal uptake of angiotensin II, aldosterone and atrial natriuretic peptide showed no significant differences between control and stimulation groups. The renal uptake of glucagon increased significantly during amino acid stimulation with no concomitant GFR increase. We conclude that in this experimental, non-obstructed model, RFR is a very insensitive measure, which cannot be used to discriminate between obstruction and simple dilatation in hydronephrosis. Further, our study does not support the hypothesis that glucagon is involved in GFR changes after amino acids.     

The clearance of iohexol as a measure of the glomerular filtration rate in children with chronic renal failure.

The plasma clearances of technetium-99m-labelled DTPA ([99Tcm]-DTPA) and the non-ionic contrast medium iohexol were estimated in 11 children with chronic renal failure for determination of the glomerular filtration rate (GFR). Equal values were obtained with the two substances provided plasma sampling was simultaneous, but when plasma was sampled within 3.5 h after injection of iohexol and [99Tcm]-DTPA the GFR was overestimated by more than 50%. For clearance values below 20 ml min-1 1.73 m-2, valid GFR estimates were obtained both from two plasma samples taken 3 h and 24 h after the injection of iohexol and from a single plasma sample taken 24 h after the injection.     

Non-invasive determination of the distribution of cardiac output in man at rest and during exercise

Summary. The distribution of cardiac output, as expressed by the regional uptake of thallium-201 following injection, has been studied by whole body scanning with a gamma-camera in six healthy persons and eight patients with aortic valvular disease. In the patients, cardiac output at rest and during exercise was also measured by the dye dilution technique. Combining the values of cardiac output and regional thallium uptake enabled the calculation of organ blood flow. The myocardial uptake of thallium at rest was 3·2 ± 0·32% in the control group, which is significantly lower than 8·3 ± 1·52%, found in the patients. The corresponding values measured in the kidneys were 12·5 ±1·91% in the healthy subjects and 7·1 ± 0·50% in the patient material. Myocardial uptake increased and kidney uptake decreased in both groups following injection at peak exercise. Thallium uptake in the legs increased from about 13% at rest to about 39% at exercise in both groups. Distribution of thallium after injection at peak exercise did not, however, vary significantly between the two groups in the kidneys, abdominal area or the legs. Further methodological work is required before it can be ascertained to what extent the regional thallium uptake reflects the distribution of cardiac output. We nevertheless propose that the technique should be explored further, since it appears to be a simple non-invasive means of visualizing the distribution of the cardiac output in man under certain conditions.