Transitional urinary tract

Tnmorigenicity The possible association of artificial sweeteners and urinary tract tumors is controversial. In a case-control study in Argentina in 197 patients with histologically confirmed transitional urinary tract tumors and 397 controls with acute, non-neoplastic, and non-urinary tract diseases between 1999 and 2006, 51 of the former (26%) and 87 of the latter (22%) had used artificial sweeteners [8. The risk of urinary tract tumors was significantly increased in long-term users (10 years or more). The odds ratio for long-term consumers was 2.18 (95% Cl = 1.22, 3.89) and for short-term users 1.10 (0.61, 2.00) after adjustment for age, sex, BMI, social status, and years of tobacco use. 

Harker WG, Meyers FJ, Freiha FS, et al. Cisplatin, methotrexate, and vinblastine (CMV) an effective chemotherapy regimen for metastatic transitional cell carcinoma of the urinary tract a Northern California Oncology Group study. J Clin Oncol 1985 3 1463-1470. 

Oral bropirimine is an immunostimulant that has been used in the management of transitional cell carcinoma of the bladder and upper urinary tract. It is supposedly an interferon inducer. In clinical trials, bropirimine produced mild adverse effects in about 30% of patients. Nausea or vomiting were the most common (21% of patients), and headache, transient liver enzyme rises, skin rash, and arthralgia were observed in 5-14% (1). Tachycardia or chest pain occurred in 5%. Adverse effects required drug withdrawal in 15% of patients (2). 

Urinary tract tumors Renal carcinoma has been associated with analgesic abuse an order of magnitude greater than in non-abusers (52-54), and the causal association has been recognized since 1965 (SEDA-6,81) and repeatedly confirmed. In 1984 an authoritative consensus conference in the USA pointed to the evidence that very heavy and sustained use of some analgesic mixtures without phenacetin can also predispose to cancer of the urinary tract, particularly transitional cell carcinoma of the renal pelvis (55). 

Gonwa TA, Corbett WT, Schey HM, Buckalew VM Jr. Analgesic-associated nephropathy and transitional cell carcinoma of the urinary tract. Ann Intern Med 1980 93(2) 249-52. 

Soloway MS, Briggman JV, Carpinito GA, et al. Use of a new tumor marker, Urinary NMP22, in the detection of occult or rapidly recurring transitional ceU carcinoma of the urinary tract following surgical treatment. J Urol 1996 156 363-67. 

The lower urinary tract consists of the bladder, urethra, urinary or urethral sphincter, and the surrounding musculofascial structures including connective tissue, nerves, and blood vessels. The urinary bladder is a hollow organ composed of smooth muscle and connective tissue located deep in the bony pelvis in men and women. The urethra is a hollow tube that acts as a conduit for urine flow out of the bladder. The interior surface of both the bladder and urethra is lined by an epithelial cell layer termed transitional epithelium, which is in constant contact with urine. Previously considered inert and inactive, transitional epithelium may actually play an active role in the pathophysiology of many lower urinary tract disorders, including interstitial cystitis and UI. The urinary or urethral sphincter is a combination of smooth and striated muscle within and surrounding the most proximal portion of the urethra adjacent to the bladder in both men and women. This is a functional but not anatomic sphincter that includes a portion of the bladder neck or outlet as well as the proximal urethra. 

Moreover, the types of tumors associated wifii bacterial cystitis and calculi, as well as with other infectious inflammatory processes in the bladdm, such as schistosomiasis, frequently are squamous cell carcinomas, in contrast to the usual transitional (urothelial) ceU carcinomas that occur in the bladdm (Oyasu 1995). In rodents, the tumors associated with urinary tract solids are for the most part transitional (mothelial) cell tumors rather than squamous ceU proliferations. 

The asymmetric unit membrane that is unique to the umbrella cells of urinary tract transitional epithelium contains a transmembrane protein that is unique to uro-thelium. In studies performed thus far, the uroplakins are highly specific for transitional epithelium, with moderate sensitivityand are not seen in squamous epithelial tissue. 

Langner C, Ratschek M, Tsybrovskyy O, et al. P63 immuno-reactivity distinguishes upper urinary tract transitional-cell catcinoma and renal-cell carcinoma even in poorly differentiated tumors./Histochem Cytochem. 2003 51 1097-1099. 

Moderate atypia and atypical hyperplasia of the urothelium were first described in 4 pieces of nephroureterectomies performed in 3 CHN patients prior or at time of transplantation [28]. Then, three cases of cancers of the urinary tract were reported the first case, a 28 year old woman with CHN, developed two papillary transitional cell carcinomas in the posterior bladder wall 12 months after a renal transplantation [31] the second case, a 42 year old woman with CHN, presented with hematuria secondary to a papillary transitional cell carcinoma of the right pelvis [32]. The third case was a 49 year old woman previously published as... 

Transitional cell carcinoma of urinary tract Malignant melanoma... 

The uroplakins are urothelium-specific transmembrane proteins expressed as rigid 0.2-0.5 pm plaques on the apical surface of mammalian urothelium. They are important for the differentiation of urothelium and take part in strengthening of the urothelial apical surface during distention of urinary bladder and urinary tract. Uroplakins are divided in four subtypes la, Ib, II, and III all of then are expressed by the urothelium of the urinary tract and tumors originated from the urothelium. Uroplakin subtypes la and II are specific for urothelium and were not detected in any other tissue or carcinoma type other than transitional cell carcinoma. Both uroplakins... 

The causes for ureteric obstruction are best divided into intra-luminal lesions, pathology affecting the wall of the ureter, and extrinsic causes. The commonest malignant primary tumor of the ureter is transitional cell carcinoma (TCC). Patients with ureteric TCC frequently have a previous history of TCC elsewhere in the urinary tract. Squamous carcinoma and metastases (classically from melanoma, uncommonly from breast or bronchus) are rare. 

Transitional cell carcinoma (TCC) of the upper and lower urinary tract usually occurs in the sixth and seventh decades. 

Transitional cancer is usually located in the urinary bladder and is diagnosed by means of cystoscopy. Up to 20% of urothelial carcinomas develop in the upper urinary tract, with 25% of these tumors being located in the upper tract of the ureter. The vast majority of the upper-tract TCC are superficial tumors and of low stage. Only about 15% of the upper-tract carcinomas are infiltrating tumors. The patients usually present with hematuria, and in a third of the patients, flank pain and acute renal colic is present. 

Fritz GA, Schoellnast H, Deutschmann HA, Quehenberger F, Tillich M (2006) Multiphasic multidetector-row CT (MDCT) in detection and staging of transitional cell carcinomas of the upper urinary tract. Eur Radiol 16 1244-1252... 

Transitional epithelium of sheep urinary tract Rat eyes... 

Candiotti, A., Ibanez, N., and Monis, B., 1972, Sialidase of transitional epithelium of sheep urinary tract, Experientia 28 541-542. 

While most drug systems evaluated have shown passive diffusional characteristics, Levy and Jusko have reported that the oral absorption of riboflavin in man possesses characteristics indicative of specialized transport mechanisms. The evidence in support of such a conclusion was based on the finding that as the dose of riboflavin was increased, the per cent absorbed (based on urinary recovery) decreased. This effect was observed only in fasted patients and was not observed when riboflavin was administered with a meal. The authors suggest that the presence of food in the alimentary tract delays the transit time of riboflavin, thus keeping it in the presence of absorptive sites for longer periods of time. 

A FIGURE 6-4 Principal types of epithelium. The apical and basolateral surfaces of epithelial cells exhibit distinctive characteristics, (a) Simple columnar epithelia consist of elongated cells, including mucus-secreting cells (in the lining of the stomach and cervical tract) and absorptive cells (in the lining of the small intestine), (b) Simple squamous epithelia, composed of thin cells, line the blood vessels (endothelial cells/endothelium) and many body cavities, (c) Transitional epithelia, composed of several layers of cells with different shapes, line certain cavities subject to expansion and contraction (e.g., the urinary bladder). 

The amormt of absorbed riboflavin that can remain within the body and the circulation (in blood plasma) is strictly regulated by glomerular and tubular filtration and tubular reabsorption in the kidneys. The latter is an active, saturable, sodium-dependent transport process, with characteristics similar to those of active transport in the gastrointestinal tract. It is responsible for the very sharp and characteristic transition between minimal urinary excretion of riboflavin at low intakes, and a much higher level of excretion, proportional to intake, at higher intakes. This transition point has been extensively used to define and to measure riboflavin status and requirements (see below), and to permit studies of intestinal absorption in vivo (see above). Excretion of riboflavin is affected by some chemicals (such as boric acid, which complexes with it), and by certain diseases and hormone imbalances. 

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