Urolithiasis in renal and combined pancreas/renal transplant recipients

PURPOSE: Urological complications in renal transplant recipients will become more common with increasing numbers of transplantations as well as increased graft survival secondary to improvements in immunosuppression. Urinary stone disease may be one of those complications. We determine the current incidence of urinary stone disease in renal transplant patients based on contemporary immunosuppressive regimens. MATERIALS AND METHODS: We reviewed the records of 1,730 renal and 83 pancreas/renal transplantations performed during the cyclosporine era and identified 8 recipients (0.4%) with urinary stone disease, including 3 with renal pelvic stones, 1 with multiple ureteral stones and 4 with bladder calculi. RESULTS: Treatment ranged from conservative observation to open pyelolithotomy, and included percutaneous nephrolithotomy and extracorporeal shock wave lithotripsy. The ureteral stones were removed with antegrade and retrograde ureteroscopy. The 4 bladder stones were treated with cystolithalopaxy. No case had significant permanent graft damage. Mean followup was 68.6 months. Mean serum creatinine was 1.5 mg./dl. (normal 0.5 to 1.3) at baseline and 2.38 after followup. CONCLUSIONS: While the incidence of upper tract urinary stone disease in renal (0.23%) and pancreas/renal (1.2%) transplant recipients is not statistically significant (p <0.45), the latter have significantly higher rates of bladder stones (4.8 versus 0%, p <0.001). The diagnosis of urinary stone disease in transplant recipients can be challenging because of the lack of symptoms but the treatment approach is the same as in the normal population.     

A model for the evaluation of search queries in medical bibliographic sources

The aim of this study was to develop a model to evaluate the retrieval quality of search queries performed by Dutch general practitioners using the printed Index Medicus, MEDLINE on CD-ROM, and MEDLINE through GRATEFUL MED. Four search queries related to general practice were formulated for a continuing medical education course in literature searching. The selected potential relevant citations from the course instructor and the 103 course participants together served as the basic set for the three judges to evaluate for (a) relevance and (b) quality, with the latter based on journal ranking, research design and publication type. Relevant individual citations received a citation quality score from 1 (low) to 4 (high). The overall search quality was expressed in a formula, which included the individual citation quality score of the selected and missed relevant citations, and the number of selected non-relevant citations. The outcome measures were the number and quality of relevant citations and agreement between the judges. Out of 864 citations, 139 were assessed as relevant, of which 44 citations received an individual citation quality score of 1, 76 of 2, 19 of 3 and none of 4. The level of agreement between the judges was 68% for the relevant citations, and 88% for the non-relevant citations. We describe a model for the evaluation of search queries based not only on the relevance, but also on the quality of the citations retrieved. With adaptation, this model could be generalized to other professional users, and to other bibliographic sources.     

Reactive oxygen species-induced apoptosis and necrosis in bovine corneal endothelial cells

PURPOSE: The loss of corneal endothelial cells associated with aging and possibly other causes has been speculated to be related to exposure to reactive oxygen species (ROS). The current study was conducted to investigate, by use of photosensitizers, the underlying mechanisms involved in the death of bovine corneal endothelial cells (BCENs) caused by ROS. METHODS: BCEN cells in primary culture were treated with a photosensitizer (riboflavin or rose bengal) with light exposure. The patterns of cell damage and death were assessed using an acridine orange-ethidium bromide differential staining method, TdT-mediated dUTP nick-end labeling (TUNEL) assay, and transmission electron microscopy. The cytotoxicity was assayed by mitochondrial function using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) testing. Antioxidants, including catalase, L-histidine, salicylic acid, and superoxide dismutase, were used to determine the types of ROS involved. Activation of nuclear factor (NF)-kappaB was examined by fluorescent immunocytochemistry with anti-p65 antibody. RESULTS: Light-irradiated riboflavin or rose bengal resulted in a significant decrease in viability of BCEN cells. Chromosomal condensation and fragmentation were observed in apoptotic cells, and membrane lysis and damage of cell ultrastructures were observed in necrotic cells. Riboflavin induced apoptosis at 30 minutes and thereafter and induced necrosis after 2 hours. Rose bengal was shown to cause similar effects within half the time required for the effects of riboflavin. Catalase and salicylic acid were found to provide protection for BCENs from cytotoxic effects of riboflavin, and L-histidine was found to protect BCENs from cytotoxicity induced by rose bengal. Kinetic studies using immunocytochemistry showed that NF-kappaB was translocated into the nucleus within 15 minutes and 30 minutes after treatment with rose bengal and riboflavin, respectively. CONCLUSIONS: The cytotoxic effects of photo-irradiated riboflavin and rose bengal are shown to be mediated by two distinct but parallel pathways, one leading to apoptosis and the other to necrosis. Possible involvement of NF-kappaB in cell death is suggested. These findings provide potential leads for future investigation into the molecular mechanisms of loss of corneal endothelial cells related to aging, oxidative stress, and possibly other similar causes.     

Cardiovascular and renal effects of central administration of a mineralocorticoid receptor antagonist in conscious female rats

In a previous study we showed that in normotensive male rats brain mineralocorticoid receptor blockade induced a long lasting decrease in blood pressure associated with increased urinary excretion of water and electrolytes. Here, we report the effect of intracerebroventricular injection of a mineralocorticoid receptor antagonist (RU28318; 3,3-oxo-7 propyl-17-hydroxy-androstan-4-en-17yl-propionic acid lactone) on cardiovascular and renal function in female rats. Compared with male rats, females are less sensitive to brain mineralocorticoid receptor blockade. Administration of RU28318 (10 ng, 100 ng) caused a significant decrease in systolic blood pressure (10-12.5%) only at 8 h after injection. An increased urinary excretion of water (about 160%) and electrolytes (about 175%) during the first 8 h after the injection was observed in the 100 ng RU28318 treated group. Heart rate, food intake and water consumption were not affected at either dose. In conclusion, in conscious female rats, brain mineralocorticoid receptors participate in blood pressure and renal function control.     

Metabolism of liriodendrin and syringin by human intestinal bacteria and their relation toin vitro cytotoxicity

When liriodendrin or syringin was incubated for 24 h with human intestinal bacteria, two metabolites, (+)-syringaresinol-beta-D-glucopyranoside and (+)-syringaresinol, from liriodendrin and one metabolite, synapyl alcohol, from syringin were produced. The metabolic time course of liriodendrin was as follows: at early time, liriodendrin was converted to (+)-syringaresinol-beta-D-glucopyranoside, and then (+)-syringaresinol. The in vitro cytotoxicities of these metabolites, (+)-syringaresinol and synapyl alcohol, were superior to those of liriodendrin and syringin.     

Pathogenesis and prevention of stomach cancer.

In many Western developed countries, the incidence of stomach cancer has declined dramatically. This decrease was an extraordinary, "unplanned triumph", especially when compared to other cancers. Stomach cancer is still the most prevalent malignant tumor in Korea. Most Koreans carry Helicobacter pylori in their stomach. Thus, a new hypothesis, based on the relationship between the host and Helicobacter pylori, is presented as the carcinogenesis of human stomach cancer. The reasons for why the N-nitrosamide hypothesis should be dismissed as the etiology of stomach cancer, and why the contemporarily available principles and practice of intervention strategies to rapidly decrease the surprisingly high prevalence rate of Helicobacter pylori infection are impractical at this moment, are explained. In order to introduce an alternative provisional strategy of the "planned triumph" for the population vulnerable to stomach cancer, vitamin C is defined as an anti-inflammatory agent on the basis of the pathogenesis of Helicobacter pylori infection.     

Legal proof of child sexual abuse in the absence of physical evidence

Child sexual abuse criminal court cases from a 12-month period were reviewed to determine the frequency and significance of physical evidence in legally "proven" felony cases with penetration. One hundred fifteen consecutive cases were reviewed, and 87 (76%) had resulted in conviction of the perpetrator on felony charges. Charges of vaginal rape were made in 88 cases, and oral and/or anal sodomy in 67 cases. Physical evidence was present in only 23% of all cases that resulted in felony convictions. Felony convictions were obtained in 67 (79%) of 85 cases without physical evidence and in only 20 (67%) of 30 cases with physical evidence. Eight of the 10 cases without physical evidence that did not result in conviction involved victims younger than 7 years of age. Cases involving the youngest victims had a significantly lower conviction rate (12 of 23), despite a very high frequency (13 of 23) of physical evidence (P less than .0005). Physical evidence was neither predictive nor essential for conviction. Successful prosecution, particularly in cases involving the youngest victims, depended on the quality of the verbal evidence and the effectiveness of the child victim's testimony.     

Validity of a risk-related patient-administered medical questionnaire for dental patients.

In this study the validity of a patient-administered risk-related medical questionnaire for dental patients was tested. The answers given on the questionnaire were compared with the results of a verbal history taken by a physician. This verbal history was considered the "gold standard." The sensitivity and specificity of the medical questionnaire appeared to be sufficiently high, and the kappa values of the separate questions were satisfactory. The questionnaire was found to be valid in the registration of medical problems in dental patients, but combination of the two methods is recommended.