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Renal hypouricemia is an inherited disorder characterized by impaired renal urate (uric acid) reabsorption and subsequent low serum urate levels, with severe complications such as exercise-induced acute renal failure and nephrolithiasis. We previously identified SLC22A12, also known as URAT1, as a causative gene of renal hypouricemia. However, hypouricemic patients without URAT1 mutations, as well as genome-wide association studies between urate and SLC2A9 (also called GLUT9), imply that GLUT9 could be another causative gene of renal hypouricemia. With a large human database, we identified two loss-of-function heterozygous mutations in GLUT9, which occur in the highly conserved "sugar transport proteins signatures 1/2." Both mutations result in loss of positive charges, one of which is reported to be an important membrane topology determinant. The oocyte expression study revealed that both GLUT9 isoforms showed high urate transport activities, whereas the mutated GLUT9 isoforms markedly reduced them. Our findings, together with previous reports on GLUT9 localization, suggest that these GLUT9 mutations cause renal hypouricemia by their decreased urate reabsorption on both sides of the renal proximal tubules. These findings also enable us to propose a physiological model of the renal urate reabsorption in which GLUT9 regulates serum urate levels in humans and can be a promising therapeutic target for gout and related cardiovascular diseases.

The profibrotic effect of plasminogen activator inhibitor-1 (PAI-1) in renal fibrosis is widely recognized, but its mechanism remains controversial especially in chronic progressive kidney disease. In the present study, pioglitazone (Pio) and candesartan (CD), which are reported to inhibit PAI-1, were administered to spontaneously hypercholesterolemic (SHC) rats, a model of chronic progressive kidney disease. Therapeutic effects and effects on the intrarenal plasmin cascade were examined. Eight-wk-old SHC rats were used as controls. Oral administration of vehicle alone, Pio, or CD was performed starting at 8 wk of age and was continued for 24 wk. The degree of renal fibrosis was evaluated by sirius red staining of kidney sections and by total collagen assay of renal homogenates. The renal PAI-1 protein level was assessed by Western blotting, and plasmin activity was analyzed by chromogenic assay and casein gel zymography. Urinary protein and blood urea nitrogen were significantly increased in the vehicle-treated group, but the increase was attenuated in the Pio- and CD-treated groups. This correlated well with the degree of fibrosis as assessed by sirius red staining and total collagen assay. The PAI-1 protein level was also increased significantly in the vehicle-treated group, and the increase was attenuated in the Pio- and CD-treated groups. Despite the presumed plasmin-inhibitory function of PAI-1, plasmin activity changed in parallel with PAI-1. These results suggest that Pio and CD inhibit PAI-1 and exert renoprotective effects against chronic progressive renal disease, but its action is independent of the regulatory function on plasmin activity.

Purpose: To compare the midterm efficacy and safety of phacoviscocanalostomy (viscocanalostomy, phacoemulsification, and intraocular lens [IOL] implantation) and cataract surgery (phacoemulsification and IOL implantation) in patients with normal-tension glaucoma (NTG) and cataract., Setting: Sensho-kai Eye Institute, Kyoto, Japan., Methods: Thirty-one eyes had phacoviscocanalostomy, and 35 eyes had uncomplicated cataract surgery only. The intraocular pressure (IOP), postoperative antiglaucoma medications, and visual outcomes were compared between groups., Results: The mean follow-up was 34.9 months+/-19.8 (SD) (range 7 to 78 months). At 36 months, the mean preoperative IOP and postoperative IOP were 17.2+/-1.5 mm Hg and 14.1+/-1.6 mm Hg, respectively, in the phacoviscocanalostomy group and 16.7+/-1.4 mm Hg and 15.6+/-3.4 mm Hg, respectively, in the cataract surgery only group. The differences between groups were significant at all time points (P<.05). The success probabilities of the phacoviscocanalostomy group achieving 20% and 30% IOP reductions with (or without) medications were 78.5% (67.4%) and 35.5% (37.4%) at 24 months and 58.0% (44.2%) and 28.0% (26.6%) at 48 months, which were significantly better than the probabilities in the cataract surgery only group, which were 16.0% (9.5%) and 5.7% (2.9%) at 24 months (P<.001 for each comparison, Kaplan-Meier life-table analysis with log-rank test). Based on the modified Aulhorn-Greve classification, the visual acuity and visual fields did not deteriorate in the phacoviscocanalostomy group; the visual fields deteriorated in 6 eyes in the cataract surgery only group during the follow-up (P=.024)., Conclusion: Phacoviscocanalostomy lowered IOP and maintained postoperative visual outcomes; it was safe and effective in elderly patients with coexisting NTG and cataract.

Background: Airline flight personnel work in a unique environment with exposure to known or suspected carcinogens and mutagens including ionizing cosmic radiation. A meta-analysis was conducted to study whether the occupational exposure of female flight attendants (FA) increased their relative risk of cancer incidence., Methods: A bibliographical computer search from 1966 to 2005 of cancer incidence cohort studies of female FA was performed. Combined relative risks (RRc) in cancer incidence were calculated by means of meta-analysis., Results: RRc and 95% confidence interval (CI) for malignant melanoma and breast cancer in female FA were 2.13 (95% CI: 1.58-2.88) and 1.41 (1.22-1.62) (p < 0.0001). Excess risk was not significant for all-site cancer with RRc of 1.10 (0.99-1.21)., Conclusions: The meta-analysis confirmed the significantly increased risks for malignant melanoma and breast cancer in female FA. Increased exposure to cosmic radiation during flight has been suggested as a potential occupational risk factor. Ultraviolet radiation exposure on board seems an unlikely occupational risk, but nonoccupational leisure time sun exposure is a possible risk factor. The etiology of the observed increase in incidence of some cancers remains controversial because assessment of possible confounders, especially nonoccupational exposure factors, has thus far been limited.

The value of fluorescence in situ hybridization (FISH) as an aid to deciding the prognosis for lung carcinoma patients, comparing quantitatively the signal from the p53 gene (17p13.1) on chromosome 17, was studied. A dual-labeling technique was used, using probes for the centromeric region of chromosome 17 and for the p53 gene locus. FISH was used on frozen sections of 68 surgically resected lung carcinoma (20 adenocarcinoma; 37 squamous cell carcinoma; 11 large, small, and other cell carcinoma). Hybridization signals were counted for 100-200 interphase nuclei per specimen using a Zeiss confocal laser scanning microscope (Carl Zeiss, Oberkochen, Germany) equipped with a bandpass filter for diaminophenolindole and a longpass filter for rhodamine. Clinicopathologic data were evaluated using the Statistical Analysis System. Chromosome 17 polysomy (three or more signals) was greater in poorly differentiated than in well-differentiated lung carcinoma (P < 0.05). p53 deletion correlated with p53 immunostaining (P < 0.05). Thus, analysis by FISH using DNA probes for chromosome 17 and p53 may be of some, albeit limited, value in determination of prognosis.

Purpose: Other than age, the risk factors for postherpetic neuralgia are not well established. We studied whether the concentration of interleukin 8 in the cerebrospinal fluid is associated with the risk of postherpetic neuralgia., Methods: We enrolled 170 patients more than 50 years old who had a typical painful and nontrigeminal herpetic rash. Patients were treated with acyclovir; no corticosteroids were given. Cerebrospinal fluid was taken for analysis of interleukin 8 during and at full crusting of the herpetic rash. Age, sex, comorbid conditions, prodromal pain, localization and severity of herpetic rash, number of skin lesions, and degree of pain were recorded. We used multivariate logistic regression modeling to identify significant predictive factors. Receiver operating characteristic (ROC) curves were evaluated to determine the contribution of each factor., Results: Six months after healing, 31 patients (18%) had postherpetic neuralgia; 27 patients still had it after 1 year. Only three variables-age (odds ratio [OR] = 2.7 per 10-year increase; 95% confidence interval [CI]: 1.2 to 6.2), acute pain (OR = 1.8 per unit increase in visual analog scale; 95% CI: 1.2 to 2.8), and interleukin 8 concentration in the cerebrospinal fluid at full crusting of the herpetic rash (OR = 1.6 per 20-microg/L increase; 95% CI: 1.3 to 2.0)-were significant predictors of postherpetic neuralgia at 1 year. Interleukin 8 concentration also had the highest area under the ROC curve at these evaluation points (P <0.001)., Conclusion: Our results suggest that interleukin 8 concentration in the cerebrospinal fluid at full crusting of herpetic rash may be useful for identifying patients who are likely to develop intractable postherpetic neuralgia.