Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.49 (reverse transcriptase)
 31,746 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

New, noninvasive methods for the early detection of urothelial carcinomas of the urinary bladder are needed for the diagnosis, follow-up, and screening of patients with bladder cancer. Detection of the enzyme telomerase in urine could offer these new diagnostic possibilities. The standard technique for detecting telomerase activity is the telomeric repeat amplification protocol (TRAP assay). Because of the instability of the ribonucleoprotein telomerase in an aggressive medium, such as urine, investigations conducted to date have yielded nonuniform or even contradictory findings. This study compares the detection of human telomerase RNA (hTR) by reverse transcriptase-PCR (RT-PCR) with detection of telomerase activity by the TRAP assay in the diagnosis of urothelial carcinoma of the urinary bladder. Sedimented cells obtained from urine of 30 patients with urothelial carcinoma, 15 patients with benign urological disorders, 3 patients as part of follow-up for malignant disease, and 20 healthy subjects were examined for the presence of hTR and for telomerase activity (TRAP). In patients with bladder cancer, telomerase activity was detected by the TRAP assay in only 2 of 30 specimens (7%). However, increased levels of hTR were detected by RT-PCR in 25 of the same 30 cases (83%). For patients with benign urological disorders, such as urolithiasis or urinary tract infections, hTR was detected in samples obtained from 4 of 15 patients (27%). Low hTR expression levels were found in 15% of the healthy controls. The detection of hTR by RT-PCR represents a promising new method for detecting malignant cells in urine.
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PMID:Comparison of human telomerase RNA and telomerase activity in urine for diagnosis of bladder cancer. 971 24

In people infected with the human immunodeficiency virus (HIV) both the CD4 T-cell count and the viral load are used to monitor disease progression to acquired immunodeficiency syndrome (AIDS). CD4 counts of <500/mm(3) are associated with opportunistic infections and certain malignancies, so-called 'AIDS-defining' conditions. Highly active antiretroviral therapy, using combinations of reverse transcriptase inhibitors and/or protease inhibitors, can improve considerably the prognosis of people who are HIV-positive, but such therapy is not yet widely available in many developing countries. People with AIDS are predisposed to urinary tract infection (UTI) by uncommon bacteria and pathogens, e.g. fungi, parasites and viruses, which may affect any urogenital organ; treatment should be culture-specific and long-term, because there is a tendency to recurrence, infection with multiple organisms and resistant isolates. Voiding dysfunction in patients with AIDS is usually a result of neurological complications caused by opportunistic infections, and has a poor prognosis. Of patients with AIDS, 30-50% develop a cancer, especially Kaposi's sarcoma (KS) and non-Hodgkin's lymphoma (NHL). KS may involve any urogenital organ, but is usually part of systemic disease. Small lesions on the external genitalia can be treated with laser, cryotherapy or surgical excision, larger lesions with radiotherapy, and disseminated or visceral KS with multidrug chemotherapy. NHL may involve the kidneys, testes and retroperitoneal lymph nodes, thus obstructing the ureters, which may require ureteric stenting or percutaneous nephrostomy. NHL can be treated with radiotherapy and combination chemotherapy. Urolithiasis in patients with AIDS may be caused by indinavir, a protease inhibitor, but the more common types of stones may also occur. Fluid-electrolyte and acid-base disturbances are common in patients with advanced AIDS, secondary to vomiting, diarrhoea, malnutrition or septicaemia. HIV-associated nephropathy occurs in 10-30% of patients, and often leads to renal failure. Testicular atrophy is common, leading to infertility, erectile dysfunction (ED) and decreased libido. Treatment for ED must include counselling about strategies to reduce the transmission of HIV. The risk of HIV transmission after parenteral exposure to blood from an HIV-positive patient is relatively low (0.2-0.4%); the urologist can reduce the risk of transmission during surgery by adopting certain precautions. After occupational exposure to HIV, chemoprophylaxis with antiretroviral medication can significantly reduce the probability of HIV transmission.
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PMID:The urological management of the patient with acquired immunodeficiency syndrome. 1692 74

We describe the first case of efavirenz-induced urolithiasis in a 47-year-old HIV-positive patient. Urinary obstruction led to pyelonephritis and septic shock, requiring emergency ureteral catheterisation. The subsequent clinical course was favourable, allowing the patient's discharge on day 5. A 7 mm, radio-translucent, non-crystalline, beige stone was extracted during catheterisation. Stone analysis by Fourier transform infrared spectrometry, liquid chromatography and mass spectrometry revealed a stone composed of efavirenz (EFV) metabolites M4, M5, M8 (as described by Mutlib et al. in 1999) and approximately 50% of unspecified proteins. EFV is a non-nucleoside reverse transcriptase inhibitor introduced to European markets in 1999. It is principally metabolised by cytochrome P450 3A4 and 2B6. Of the dose, 14-34% is excreted in the urine, 1% as unchanged drug. The patient had been taking 600 mg EFV per day for 3 years. As EFV-induced urolithiasis has not been reported so far, we would like to draw the attention of the medical community to this potentially severe complication.
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PMID:Efavirenz-induced urolithiasis. 1662 85