Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0403608 (ureter)
 9,655 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Laparoscopic nephrolysis was performed in an 81-year-old man with recurrent chyluria. A total of five trocars were used for approaching the lymphatic ducts over the right ureter and renal hilum. The lymphatic ducts identified were easily ligated under laparoscopic magnification. The recovery of this patient was quick and uneventful. The follow-up urinalysis for chyle was negative, and his serum albumin concentration increased from 3.0 g/dL to 4.2 g/dL at 2 years postoperatively. This case report attests to the long-term efficacy of a laparoscopic approach to ligation of lymphatic fistulas for the treatment of recalcitrant chyluria.
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PMID:Laparoscopic nephrolysis for chyluria: case report of long-term success. 853 60

Two possible sites of renal metabolism exist: intracellular, by enzymes within the peritubular cells, and intraluminal, by ecto-enzymes embedded on the brush border membrane. The esterolysis of enalapril to its dicarboxylate metabolite, enalaprilat, was studied in the isolated perfused, nonfiltering rat kidney preparation (NFK) and compared with that observed for the isolated perfused rat kidney (IPK) to ascertain the site of metabolic conversion. For the NFK, filtration was obliterated with the high oncotic pressure (8% bovine serum albumin in plasma) and ligation of the ureter, thus preventing enalapril from reaching intraluminal sites by filtration. The steady-state renal plasma clearance of enalapril in the NFK was 2.0 ml/min/g, a value similar to that (2.1 ml/min/g) observed previously for the IPK. The rate of appearance of enalaprilat, the metabolite, in venous plasma for the NFK (30 +/- 3% of the input rate of enalapril) was also comparable with that for the IPK (27 +/- 4%). Further, identification of the site of enalapril metabolism (cellular or luminal) was aided by simulations based on physiological models and parameters obtained previously on the renal handling of enalapril and enalaprilat. These parameters were optimized to match closely the experimental observations. The predicted total and metabolic renal clearances for the IPK or for the NFK were similar for both the "cellular model" and "luminal model": in both instances, values for the NFK were 59-65% of those for the IPK. By contrast, predictions for the venous output rate of enalaprilat (as a percent of the input rate of enalapril) were different: the "cellular model" predicted no change in value between the NFK and the IPK, whereas metabolite appearance was greatly magnified for the NFK (289% that of the IPK) with luminal metabolism. The lack of difference in venous outflow of enalaprilat for the NFK and IPK was more congruent with the notion of intracellular and not intraluminal esterolysis of enalapril.
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PMID:Intracellular and not intraluminal esterolysis of enalapril in kidney. Studies with the single pass perfused nonfiltering rat kidney. 953 19

Several clinical studies have confirmed that histomorphometric changes in the tubulointerstitial compartment contain the best correlating parameters to predict the development of progressive renal insufficiency. The process of interstitial fibrosis is accompanied by an influx of inflammatory cells, up-regulation of fibrogenic cytokines such as transforming growth factor-beta and basic fibroblast growth factor, transient down-modulation of their antagonists, generation and proliferation of myofibroblasts, and, finally, by accumulation of interstitial collagens and proteoglycans. A careful morphometric analysis of interstitial fibrosis requires sensitive parameters through which the severity can be quantified and by which the progression into renal insufficiency can be predicted. We have addressed these issues by morphometric analysis of both human biopsies and by refining existing experimental models in the rat. Morphometric analysis was performed using a Zeiss microscope equipped with a full colour 3CCD camera and KS-400 image analysis software from Zeiss-Kontron. For studies with human material, biopsies were examined from patients with various renal diseases including patients with chronic allotransplant dysfunction. The development of interstitial fibrosis was correlated with clinical parameters. In experimental models, we analysed the interstitial composition and eventual glomerular alterations in rats with bovine serum albumin (BSA)-induced protein overload nephropathy and with human IgG-induced chronic serum sickness nephritis. Finally, we adapted and refined the model of ureter obstruction-induced interstitial fibrosis in the rat. For this purpose, custom-made titanium clips (S&T, Neuhaus, Switzerland) were implanted around the ureter in the abdomen of rats to obstruct the ureter without causing necrosis. The clips were removed at various time points after obstruction of the ureter (1-14 days). The subsequent remodelling of the interstitium was studied thereafter, in order to establish whether uraemia-induced interstitial fibrosis remains reversible at all times. In rat models, we have found that both protein overload-induced and serum sickness-induced interstitial fibrosis are accompanied by the development of focal and segmental glomerulosclerosis. Only in the ureter obstruction model did selective interstitial fibrosis develop, and remained reversible at all times studied. For the reliable assessment of interstitial fibrosis we have found that the best correlating parameters of interstitial fibrosis with renal function were: (i) the ratio of protein accumulation of TGF-beta-1 and its antagonist decorin; (ii) interstitial expression of smooth muscle alpha-actin; and (iii) accumulation of interstitial collagens (as determined by immunoperoxidase and by Sirius red staining).
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PMID:Morphometry of interstitial fibrosis. 1114 98

The maintenance of depletion of antibody (Ab) reactive with Galalpha1-3Gal (Gal) on pig vascular endothelial cells by the intravenous (i.v.) infusion of a synthetic Gal conjugate has been proposed as a means of delaying Ab-mediated rejection of transplanted pig organs in primates. We have therefore studied the effect of the continuous i.v. infusion of bovine serum albumin conjugated to multiple synthetic Gal type 6 oligosaccharides (BSA-Gal) on anti-Gal Ab levels and on graft survival in baboons undergoing pig kidney transplantation. Group 1 baboons (n=3) underwent extracorporeal immunoadsorption of anti-Gal Ab, a cyclophosphamide (CPP)-based immunosuppressive regimen, and a non-transgenic pig kidney transplant. Group 2 (n=2) were treated identically to Group 1 but, in addition, received a continuous i.v. infusion of BSA-Gal. Group 3 (n=2) were treated identically to Group 2, but without CPP. A single baboon (Group 4) underwent extracorporeal immunoadsorption, a CPP-based regimen, and continuous i.v. BSA-Gal therapy for 28 days, but did not receive a pig kidney transplant. Two of the transplanted pig kidneys in Group 1 were excised on post transplant days 7 and 13 for a rejected ureter, and disseminated intravascular coagulation (DIC), respectively. The third baboon died of sepsis on day 6. All transplanted ureters and kidneys showed some histopathologic features of acute humoral xenograft rejection. Group 2 baboons were euthanized on days 8 and 11, respectively, for liver failure. At autopsy, there were histopathological features of widespread liver necrosis, but the pig kidneys and ureters showed no features of rejection. The pig kidneys in Group 3 baboons were excised for renal vein thrombosis (day 9) and DIC (day 12); there was no histological signs of rejection in the pig kidneys or ureter, although there were focal areas of modest liver injury in one baboon on biopsy. The single Group 4 baboon showed no biochemical or histological features of liver injury. Anti-Gal Ab levels returned in Group 1, but were maintained at negligible levels in the baboons in Groups 2 to 4 that received BSA-Gal therapy. Continuous i.v. therapy with BSA-Gal is largely successful in maintaining depletion of circulating anti-Gal antibodies and in preventing or delaying Ab deposition and acute humoral xenograft rejection in porcine grafts, but may be associated with liver injury when administered in the presence of a pig kidney transplant and CPP therapy. The mechanism of the hepatic injury remains uncertain.
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PMID:Pig kidney transplantation in baboons treated intravenously with a bovine serum albumin-Galalpha1-3Gal conjugate. 1470 29

Control of bleeding is one of the most technically challenging steps in laparoscopic renal surgery, especially partial nephrectomy. Although there is no consensus on how best to approach hemostasis, the options continue to expand. The original method of sutured renorrhaphy is, perhaps, the most effective; however, great skill is needed to avoid prolonged warm ischemia. Tissue sealants and adhesives serve as a barrier to leakage and as a hemostat. The four classes are fibrin sealants, collagen-based adhesives, hydrogel, and glutaraldehyde-based adhesive. Additionally, oxidized cellulose can be applied to the surface of kidney or used as a bolster. Fibrin sealants are self-activating and work best on a dry field. The gelatin matrix agent consists of human-derived thrombin with a calcium chloride solution and bovine-derived gelatin matrix. The fibrinogen required to form a clot comes from autologous blood. Another product is polyethylene glycol-based hydrogel, which acts as a mechanical sealant. The tissue glue consists of bovine serum albumin and glutaraldehyde, which cross-link to each other, as well as to other tissue proteins. Excessive use or spillage around the renal pelvis and ureter may compromise urinary flow. The methylcellulose products, consisting of oxidized cellulose sheets, usually are positioned within a sutured bolster and act in part by providing direct pressure. A number of energy-based technologies also have been utilized. Monopolar cautery consists of a high-frequency electrical current delivered from a single electrode. Care must be taken to avoid injurious current transfer to surrounding structures. With bipolar cautery, hemostasis occurs only between the electrodes. In the argonbeam coagulator, argon, an inert non-flammable gas that clears from the body rapidly, is coupled with an electrosurgical generator. The gas creates a more even distribution of the energy and better sealing of the tissues. There have been a few reports of serious complications, including gas embolism and tension pneumothorax. The holmium:YAG laser simultaneously dissects and coagulates tissue. However, its use may be limited by smoke and by blood splashing onto the camera lens, and the tissue vaporization and liquid could promote tumor-cell spillage. The potassium-titanyl-phosphate (KTP) and diode lasers have shown promise in animal studies. The saline-coupled radiofrequency tool uses a standard electrosurgical generator to deliver energy through the conductive fluid. The fluid keeps the surface temperature much lower, increases the contact area, and reduces char and eschar formation. One caveat for the use of instruments that coagulate and ablate tissue is that they can damage the collecting system. Furthermore, the char can make it difficult to assess margin status. In practice, a combination of instruments, sealants, or both generally is utilized to obtain hemostasis. These multimodality efforts may be especially useful in the patient with compromised renal function. On the other hand, the cost can rise quickly when multiple agents are employed. Combining suturing and hemostatic technology may be the best strategy.
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PMID:Hemostatic agents and instruments in laparoscopic renal surgery. 1835 35

Posttraumatic microalbuminuria may be caused by either charge- or size-selective alterations in the glomerular filtration barrier, or both, and/or to a reduction in proximal tubular protein reabsorption. This study was performed to elucidate the pathophysiology of the increases in glomerular permeability occurring in rats exposed to a laparotomy or to a laparotomy and muscle trauma. In anesthetized Wistar rats (250-280 g), the left ureter was cannulated for urine collection, while simultaneously blood access was achieved. Rats were exposed to trauma by a laparotomy (L; n = 8), or by a combination of L and muscle trauma (MT; L+MT) induced by topical blunt injury of the abdominal muscles bilaterally. After L, muscles were crushed using hemostatic forceps at either 2 x 2 sites ("small" MT; n = 9), or at 2 x 5 sites ("large" MT; n = 9). Sham groups (n = 16), not exposed to a laparotomy, were used as controls. The glomerular sieving coefficients (theta) to polydisperse FITC-Ficoll-70/400 (molecular radius 13-80 A) were determined at 5 or 60 min after L and L+MT, respectively, from plasma and urine samples, and analyzed by high-performance size-exclusion chromatography. A tissue-uptake technique was used to assess theta for (125)I-labeled serum albumin. L, with or without MT, increased theta for Ficoll(55-80A) and albumin rapidly and markedly. Theta-Ficoll(70A) thus increased approximately threefold, and theta for albumin significantly, for all trauma groups. According to the "two-pore model" of glomerular permeability, these changes mainly reflect an increase in the number of large pores in the glomerular filter without any primary changes in the charge-selective properties of the filter.
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PMID:Loss of size selectivity of the glomerular filtration barrier in rats following laparotomy and muscle trauma. 1958 43