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)

A pulsed dye laser (Candela) was used in our lithiasis treatment center during the period 02/88-09/89 to remove 325 calculi in 278 patients, requiring 285 endoscopic instrumentations. The pulsed laser allowed to obtain fragmentation of 318 calculi, 238 of which were reduced to thin sand and 80 to coarser fragments. The latter were either cleared using a Dormia probe or further disintegrated by electrohydrolytic shock wave treatment or extracorporeal shock wave lithotripsy (ESWL). No complication imputable to laser stone fragmentation was noted. Failure of stone clearance was chiefly due to the nature and shape of the stone (black, smooth monohydrated calcium oxalate calculi). The thinness of the laser fiber has made it possible to use small caliber ureteroscopes, thereby increasing the reliability of ureteroscopy. Coupled with ESWL (EDAP LT01), this technique has caused the rate of open surgical removal of ureter confined calculi to fall from 11% to 1%.
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PMID:[Rigid ureteroscopy and the pulsed laser. Apropos of 325 treated calculi]. 221 6

1. Two kinds of transient outward currents were observed upon depolarization of single smooth muscle cells isolated from guinea-pig ureter. The major transient outward current was through Ca2(+)-activated K+ channels (IK(Ca) which had a large conductance (130 pS; 126 mM [K+]i/5.9 mM [K+]o). 2. The smaller transient outward current (ITO) was pharmacologically separated from other membrane currents in the presence of 1 mM-Cd2+ and 2 mM-tetraethylammonium(TEA+) and was selectively blocked by 3 mM-4-aminopyridine. It peaked (approximately 200 pA) within 10 ms upon depolarization from -80 to +20 mV and its half-inactivation time was approximately 50 ms at +20 mV. Half-maximum voltages (V 1/2) for activation and inactivation were about -8 and -50 mV, respectively, in the presence of 1 mM-Cd2+ and 2 mM-TEA+. The time course of recovery from inactivation of ITO was fitted with a single-exponential function (tau = 100 ms at -80 mV). A tenfold change of [K+]o resulted in a 53 mV change in the reversal potential of the tail of ITO. 3. Cadmium reduced peak ITO and shifted the voltage dependence of activation and inactivation in the positive direction in a concentration-dependent manner. The V 1/2 for inactivation in the absence of Cd2+ was estimated to be approximately -64 mV. 4. Single-channel outward currents which appeared only in the initial part of a depolarizing pulse from about -100 mV were recorded using the cell-attached patch clamp. The decay of the ensemble average of the current was similar to the macroscopic ITO under whole-cell clamp. When the holding potential was less negative, the opening probability of the channel greatly decreased. The channel conductance in normal extracellular medium was 14 pS. 5. In ureter cells ITO resembles A-type current. ITO does not contribute significantly to the repolarization of the action potential but it may regulate membrane excitability by opposing Ca2+ current activated around the threshold of the action potential.
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PMID:Characteristics of transient outward currents in single smooth muscle cells from the ureter of the guinea-pig. 221 1

At Osaka City University Hospital, we performed extracorporeal shock-wave lithotripsy (ESWL) for 1277 patients in a total of 1788 sessions using Dornier kidney lithotripter Model HM III from July, 1985 to the end of December, 1988. Among the patients with a solitary stone, 911 cases were available for the follow-up study and we have compared the results among these cases in respect to the stone location and size. The results obtained were as follows: the ratio of kidney stone to ureter stone was found to be 2.2:1 in male, and 3.8:1 in female patients. This indicates that ureter stones are more frequently found in male than in female patients. In addition, we compared the size of kidney stones found in the patients including 415 male and 243 female patients. Stones larger than 20 mm were more frequently found in female than in male patients. Moreover, a stone composition study of these patients showed that the contents of both phosphate calcium and magnesium ammonium phosphate were higher in female than in male patients. ESWL performed against stones at pelvis and calyces exhibited the best results. The results obtained with the stones less than 20 mm in diameter were especially favorable with a success rate of 100% for the stones less than 10 mm and 83% for the stones 10-20 mm, in diameter, while the results with the stones larger than 20 mm in diameter were rather poor with a success rate of 31%. ESWL performed against ureter stones showed poor results with a success rate of 63% for the stones smaller than 20 mm in diameter.
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PMID:[Evaluation of the results of extracorporeal shock-wave lithotripsy (ESWL) for solitary upper urinary tract stone]. 226 41

The rate of residual stones and that of recurrent lithiasis were investigated in 183 patients who had undergone extracorporeal shock wave lithotripsy (ESWL) between July, 1986 and December, 1988. The investigation was done by questionnaire survey at 22 institutions including our hospital on patients who were followed up after ESWL. The 183 patients included 126 male and 57 female patients between 9 and 77 years old (the mean 43.6 years). The greater part of patients had lithiasis of the lower renal calyx and upper ureter. The rate of residual stones 3 months after ESWL was 33.3% (61 patients) and the success rate was 72.2%. Chemical analysis of stones disclosed calcium oxalate-containing stones in 61% and calcium phosphate-containing ones in 10.8%. Recurrence of lithiasis was observed in 18 of the 131 patients (13.7%) who could be followed up for 6 months or more. These results were compared with those obtained after endoscopic treatment at Kinki University.
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PMID:[Follow-up study of residual and recurrent stone after extracorporeal shock wave lithotripsy]. 228 7

We treated 45 patients (46 ureteral stones) with a new pulsed dye laser. A 250 mu. fiber was used through a rigid (40 stones) or flexible (6) ureteroscope. Stones were in the upper (5 cases), middle (5) or lower (36) third of the ureter. Stone composition was calcium oxalate dihydrate (34 patients) or monohydrate (7), struvite (2) or uric acid (2). Of the calculi 36 (78%) were fragmented, including 14 that also required simultaneous basket removal of fragments. Ten stones were not fragmented: 6 because of the pure monohydrate composition and 4 due to malfunction of the laser. No damage to the ureteral wall was noted. Retrograde rigid ureteroscopy with laser lithotripsy was effective for lower and middle third ureteral stones. Flexible ureteroscopy with laser lithotripsy was effective (impacted stones) but difficult for upper third ureteral stones.
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PMID:Clinical experience with a new pulsed dye laser for ureteral stone lithotripsy. 230 58

The clinical usage of amphotericin B in treating systemic fungal infections is limited by its nephrotoxicity, which is caused by reductions in renal blood flow and alterations in renal tubular function. Aminophylline, an adenosine receptor antagonist, attenuates amphotericin B-induced reductions in renal blood flow in both dogs and rats, which suggests that endogenous adenosine may participate in this response. However, aminophylline per se is a vasodilator and also changes intracellular levels of cyclic nucleotides and calcium. In this study, we re-examined the hypothesis that adenosine participates in amphotericin B-induced renal vasoconstriction by employing a novel adenosine receptor antagonist, 1,3-dipropyl-8-(p-sulfophenyl)xanthine (DPSPX). This antagonist because of its negative charge at physiological pH, has limited access to the intracellular space. In a group of male Sprague-Dawley rats, an extracorporeal shunt was established between the carotid artery and left renal artery, via an aortic pouch, such that flow through the shunt was equivalent to renal blood flow. Also, a catheter was inserted into the left ureter for collection of urine and measurement of creatinine and electrolyte excretion. Amphotericin B-induced changes in renal blood flow and renal excretory function were measured in both control rats and rats pretreated with DPSPX at a dosage that abolishes the renovascular effects of exogenous adenosine in this model. In both control rats and rats pretreated with DPSPX, amphotericin B caused a marked decrease in renal blood flow, creatinine excretion, and potassium excretion; however, these effects of amphotericin B were similar in the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effect of an adenosine receptor antagonist on acute amphotericin B nephrotoxicity. 234 Aug 62

A method is proposed for analysing kinetic curves of the smooth muscle contraction--relaxation approved on smooth muscle preparations of ureter and taenia coli. A notion of the velocity coefficient is introduced. It is the parameter which gives a quantitative characteristics of changes in the dynamics of muscle contraction and relaxation under the effect of factors modifying the contractile response. In order to illustrate the application of this parameter studies were carried out of the effect of sodium-free medium, monensin, and of temperature decrease on the contractile activity of the smooth muscle tissue of the ureter. The method can be useful while investigating the regularities of electro- and pharmacomechanical conjunction in the smooth muscles, as well as during pharmacological screening of compounds--regulators of calcium homeostasis in myocytes and their contractile activity.
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PMID:[Kinetic analysis of contraction-relaxation process in smooth muscles]. 236 8

The paper provides the results of a study into a therapeutic effect produced by the Soviet agent Marelin used in the treatment of urolithiasis. The study was undertaken to examine 52 patients with severe nephrolithiasis, of them 33 had undergone an operation. The purpose of the study was to investigate spasmolytic, lithagogue, and anti-inflammatory effects of the drug, its impact on phosphorus and calcium exchange, uric acid metabolism, bacterial flora, urine excretion and pH. A pronounced spasmolytic effect was found almost in all the patients. Expelling of small concrements and fragments was observed in 14 cases, almost in all (80%) had crystallines of uric salts, mucus, and pus. Some of them had small calculi moved from the calyces and pelves into the ureter. No pathogenic urinary bacterial flora was found in 12.2% of the cases. Calciuria was normalized in 18 patients, reduced on an average of up to 5.2 mmol/l in 16. Phosphaturia (false or true) occurred in 20 of 52 patients, its severity diminished in two thirds of the cases. Hyperuricemia improved in 6 out of 13 patients who had oxalate calculi. With Marelin, diuresis increased in 48 of 52 patients by 25-30% and 10-20% within the first 2-9 days and the subsequent 20 days, respectively. There was a decrease in pH from 7.8 to 6.8 in some patients with urinary alkaline reaction. The findings suggest that Marelin should be recommended for its wide clinical application.
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PMID:[Marelin in the treatment of urolithiasis]. 239 35

Antidromic stimulation of sensory nerves or administration of capsaicin and SP in the guinea-pig induced vascular protein leakage with a similar pattern of distribution in different peripheral organs, characterized by a wide-spread but highly selective occurrence. The protein-extravasation responses in the tissues, following nerve stimulation or i.v. capsaicin, were highly correlated with the concentration of SP-LI. Systemic capsaicin treatment caused an almost total loss of SP-LI in visceral organs, in which the extravasation responses to capsaicin or nerve stimulation were also abolished. The ureter of the guinea-pig was most densely innervated by capsaicin-sensitive sensory nerves, which arrive at the rostral part of the ureter via the inferior mesenteric ganglion. The caudal ureter was mainly innervated from the pelvic nerves. The vascular permeability increase induced by SP or capsaicin was more pronounced in the ureter than in any other organ investigated. SP-LI, TK-LI and CGRP-LI coexist in sensory neurons of the guinea-pig and man, as shown by immunohistochemistry. These three kinds of immunoreactivity were found in sensory cell bodies with similar regional and terminal distribution patterns in both the central and peripheral areas. Systemic capsaicin treatment induced marked reduction of SP- and TK-LI in peripheral organs except for the ileum. CGRP-LI in the ureter was also sensitive to the capsaicin treatment. Characterization of the TK-LI (K12) of the guinea-pig ureter and lung, using ion-exchange chromatography and HPLC, demonstrated that at least three immunoreactive components corresponding to NKA, NPK and ELE were present. The major form of SP-LI eluted in the same position as synthetic SP. The NKA- and ELE-like components were also identified by HPLC in water extracts of human ureter. NKB was not detectable in the sensory neurons of the guinea-pig. Capsaicin caused an acute release of SP-, NKA- and ELE-like components from superfused slices of both the spinal cord and ureter of the guinea-pig in vitro. The release of tachykinins by capsaicin was calcium-dependent but tetrodotoxin-resistant. No detectable release of NKB- or NPK-LI was induced by capsaicin. Tachykinins share a common spectrum of biological activities with regard to hypotension, bronchoconstriction and protein extravasation when given systemically to guinea-pigs. The potency of the hypotensive action of tachykinins was similar. NKA and NPK evoked much stronger bronchoconstrictor effects than SP, while SP was more active than NKA in inducing vascular permeability changes.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Tachykinins and calcitonin gene-related peptide in relation to peripheral functions of capsaicin-sensitive sensory neurons. 243 Apr 27

The release of tachykinins from isolated slice preparations of the guinea-pig spinal cord and ureter was studied in vitro. Capsaicin (10 microM) caused release of substance P, neurokinin A and an eledoisin-like component from both the spinal cord and ureter. The release of tachykinins induced by capsaicin or potassium (60 mM) was calcium dependent. No detectable release of neurokinin B or neuropeptide K, an N-terminally extended form of neurokinin A, was induced by capsaicin. No detectable release of tachykinins could be demonstrated after exposure to agents which are known to activate C-fibre afferents, such as histamine, bradykinin, serotonin, prostaglandins E1, E2 or acetylcholine. Protein extravasation in the ureter, as determined by the Evans Blue extravasation technique was used as a functional correlate to the tachykinin release. Protein extravasation was induced in vivo by local intraluminal injections of capsaicin at several hundred-fold lower concentrations than those required to induce a detectable release of tachykinins in vitro. The difference may, however, partly depend on the experimental conditions and the detection limit of the tachykinin assay used. The protein extravasation response to capsaicin was absent after systemic capsaicin pretreatment, which causes a marked depletion of tachykinins in the ureter. In conclusion, capsaicin evokes release of several tachykinins from both central and peripheral endings of primary afferent neurons. The peptides released from sensory nerves in the periphery may induce effects such as protein extravasation and smooth muscle contraction.
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PMID:Capsaicin induced release of multiple tachykinins (substance P, neurokinin A and eledoisin-like material) from guinea-pig spinal cord and ureter. 243 50


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