EFFECTIVE DOSE DUE TO TERRESTRIAL GAMMA RADIATION ESTIMATED IN SOUTHERN VIETNAM BY CAR-BORNE SURVEY TECHNIQUE.

Absorbed dose rates in air from natural radionuclides were measured by a car-borne survey in southern Vietnam. The mean absorbed dose rate in air for southern Vietnam, which consists of the south-east region and the Mekong River Delta region, was 64 ± 18 nGy h-1, while rates for the two regions were 61 ± 17 and 66 ± 19 nGy h-1, respectively. These dose rates were respectively 1.2, 2.1 and 0.9 times the measured values that were calculated on the basis of activity concentrations of soil samples in a previous study. It was considered that measured dose rate in the south-east region was influenced by the presence of artificial structures such as high-rise buildings and roads. The effective dose due to terrestrial gamma radiation for southern Vietnam was calculated to be 0.55 mSv y-1 which is 1.2 times higher than the world-wide average of 0.48 mSv y-1.

Class switch recombination and somatic hypermutation of virus-neutralizing antibodies are not essential for control of friend retrovirus infection.

Toll-like receptor 7 and Myd88 are required for antiretroviral antibody and germinal center responses, but whether somatic hypermutation and class-switch recombination are required for antiretroviral immunity has not been examined. Mice deficient in activation-induced cytidine deaminase (AID) resisted Friend virus infection, produced virus-neutralizing antibodies, and controlled viremia. Passive transfer demonstrated that immune IgM from AID-deficient mice contributes to Friend virus control in the presence of virus-specific CD4+ T cells.

Infection of adult thymus with murine retrovirus induces virus-specific central tolerance that prevents functional memory CD8+ T cell differentiation.

In chronic viral infections, persistent antigen presentation causes progressive exhaustion of virus-specific CD8+ T cells. It has become clear, however, that virus-specific naïve CD8+ T cells newly generated from the thymus can be primed with persisting antigens. In the setting of low antigen density and resolved inflammation, newly primed CD8+ T cells are preferentially recruited into the functional memory pool. Thus, continual recruitment of naïve CD8+ T cells from the thymus is important for preserving the population of functional memory CD8+ T cells in chronically infected animals. Friend virus (FV) is the pathogenic murine retrovirus that establishes chronic infection in adult mice, which is bolstered by the profound exhaustion of virus-specific CD8+ T cells induced during the early phase of infection. Here we show an additional evasion strategy in which FV disseminates efficiently into the thymus, ultimately leading to clonal deletion of thymocytes that are reactive to FV antigens. Owing to the resultant lack of virus-specific recent thymic emigrants, along with the above exhaustion of antigen-experienced peripheral CD8+ T cells, mice chronically infected with FV fail to establish a functional virus-specific CD8+ T cell pool, and are highly susceptible to challenge with tumor cells expressing FV-encoded antigen. However, FV-specific naïve CD8+ T cells generated in uninfected mice can be primed and differentiate into functional memory CD8+ T cells upon their transfer into chronically infected animals. These findings indicate that virus-induced central tolerance that develops during the chronic phase of infection accelerates the accumulation of dysfunctional memory CD8+ T cells.

Nocturia and sleep quality after transurethral resection of the prostate.

OBJECTIVES: To evaluate the clinical efficacy of transurethral resection of the prostate on nocturia and sleep disorders in patients with lower urinary tract symptoms suggestive of benign prostatic obstruction. METHODS: A prospective multicenter study including lower urinary tract symptoms suggestive of benign prostatic obstruction patients with nocturia (twice or more) undergoing transurethral resection of the prostate was carried out. All patients were assessed using the International Prostate Symptom Score and the Pittsburgh Sleep Quality Index at baseline, and 6 months after transurethral resection of the prostate. RESULTS: Overall, 49 patients were included in the study. A total of 20 of them (41%) had a sleep disorder defined as a score of 5.5 or more on the Pittsburgh Sleep Quality Index global score. The nocturia score significantly correlated with component 4 of the Pittsburgh Sleep Quality Index (habitual sleep efficiency). Nocturia significantly decreased after transurethral resection of the prostate from 3.0 ± 1.2 to 1.9 ± 0.8, whereas the global Pittsburgh Sleep Quality Index score did not. In 20 patients with a sleep disorder before transurethral resection of the prostate, subjective sleep quality (component 1) and habitual sleep efficiency (component 4) significantly decreased after transurethral resection of the prostate, but this was not the case for the global Pittsburgh Sleep Quality Index score. In 16 patients with a persistent sleep disorder after transurethral resection of the prostate, International Prostate Symptom Score, voiding and storage symptoms score were higher than those of patients without a sleep disorder, although the nocturia score improved equivalently in both groups. CONCLUSIONS: Transurethral resection of the prostate diminishes nocturnal urinary frequency and partly improves sleep quality in patients with nocturia and lower urinary tract symptoms suggestive of benign prostatic obstruction. A persistent sleep disorder after transurethral resection of the prostate is associated with persistent voiding and storage symptoms.

[Optimum initial dose of silodosin for treatment of lower urinary tract symptoms associated with benign prostatic hyperplasia].

We investigated the optimum initial dose and timing of administration of α1A-adrenoceptor antagonist silodosin for treatment of lower urinary tract symptoms associated with benign prostatic hyperplasia (BPH/LUTS). Ninety-eight patients were given a 4 mg dose after breakfast (group A), 4 mg after supper (group B), or 4 mg after breakfast and after supper (group C). At baseline, 4, 8 and 12 weeks after treatment, we assessed International Prostate Symptom Score (IPSS) and quality of life (QOL) index. Twenty-five percent or less improvement of total IPSS and no improvement of QOL index compared with baseline were defined as treatment failure at each evaluation point. Otherwise treatment was considered effective. In group A and group B, patients with treatment failure at 4 or 8 weeks after treatment, the dose of silodosin was increased to 8 mg daily. At the end of the study, 83 patients were evaluable. At 12 weeks after treatment, 20 of the 31 patients in group A and 22 of the 29 patients in group B remained on the 4 mg dose ; silodosin was effective in 65 and 76% of the patients, respectively. When patients with dose escalation were included, silodosin was effective in 81 and 90% of the patients, respectively. Silodosin was effective in 18 of the 23(78%) patients in group C, although improvement of total IPSS and voiding symptom score of IPSS at 12 weeks after treatment was better in group C than in group A or group B, the difference was not significant. In patients with IPSS less than 20, the degree of improvement of IPSS was similar among the 3 groups. In contrast, in patients with IPSS of 20 or greater the degree of improvement was better in group C than in group B or group C, but the difference was not significant. Storage symptom score of IPSS was significantly improved in all 3 groups without any significant difference among the 3 groups. Three patients (52, 59 and 76 years old) experienced abnormal ejaculation. In conclusion, 4 mg of silodosin daily showed effectiveness against BPH/LUTS, but 8 mg of silodosin daily might be better for patients with severe LUTS.

The ATP synthase a-subunit of extreme alkaliphiles is a distinct variant: mutations in the critical alkaliphile-specific residue Lys-180 and other residues that support alkaliphile oxidative phosphorylation.

A lysine residue in the putative proton uptake pathway of the ATP synthase a-subunit is found only in alkaliphilic Bacillus species and is proposed to play roles in proton capture, retention and passage to the synthase rotor. Here, Lys-180 was replaced with alanine (Ala), glycine (Gly), cysteine (Cys), arginine (Arg), or histidine (His) in the chromosome of alkaliphilic Bacillus pseudofirmus OF4. All mutants exhibited octylglucoside-stimulated ATPase activity and ß-subunit levels at least as high as wild-type. Purified mutant F(1)F(0)-ATP synthases all contained substantial a-subunit levels. The mutants exhibited diverse patterns of native (no octylglucoside) ATPase activity and a range of defects in malate growth and in vitro ATP synthesis at pH 10.5. ATP synthesis by the Ala, Gly, and His mutants was also impaired at pH 7.5 in the presence of a protonophoric uncoupler. Thus Lys-180 plays a role when the protonmotive force is reduced at near neutral, not just at high pH. The Arg mutant exhibited no ATP synthesis activity in the alkaliphile setting although activity was reported for a K180R mutant of a thermoalkaliphile synthase (McMillan, D. G., Keis, S., Dimroth, P., and Cook, G. M. (2007) J. Biol. Chem. 282, 17395-17404). The hypothesis that a-subunits from extreme alkaliphiles and the thermoalkaliphile represent distinct variants was supported by demonstration of the importance of additional alkaliphile-specific a-subunit residues, not found in the thermoalkaliphile, for malate growth of B. pseudofirmus OF4. Finally, a mutant B. pseudofirmus OF4 synthase with switched positions of Lys-180 (helix 4) and Gly-212 (helix 5) retained significant coupled synthase activity accompanied by proton leakiness.

F1F0-ATP synthases of alkaliphilic bacteria: lessons from their adaptations.

This review focuses on the ATP synthases of alkaliphilic bacteria and, in particular, those that successfully overcome the bioenergetic challenges of achieving robust H+-coupled ATP synthesis at external pH values>10. At such pH values the protonmotive force, which is posited to provide the energetic driving force for ATP synthesis, is too low to account for the ATP synthesis observed. The protonmotive force is lowered at a very high pH by the need to maintain a cytoplasmic pH well below the pH outside, which results in an energetically adverse pH gradient. Several anticipated solutions to this bioenergetic conundrum have been ruled out. Although the transmembrane sodium motive force is high under alkaline conditions, respiratory alkaliphilic bacteria do not use Na+- instead of H+-coupled ATP synthases. Nor do they offset the adverse pH gradient with a compensatory increase in the transmembrane electrical potential component of the protonmotive force. Moreover, studies of ATP synthase rotors indicate that alkaliphiles cannot fully resolve the energetic problem by using an ATP synthase with a large number of c-subunits in the synthase rotor ring. Increased attention now focuses on delocalized gradients near the membrane surface and H+ transfers to ATP synthases via membrane-associated microcircuits between the H+ pumping complexes and synthases. Microcircuits likely depend upon proximity of pumps and synthases, specific membrane properties and specific adaptations of the participating enzyme complexes. ATP synthesis in alkaliphiles depends upon alkaliphile-specific adaptations of the ATP synthase and there is also evidence for alkaliphile-specific adaptations of respiratory chain components.

Three two-component transporters with channel-like properties have monovalent cation/proton antiport activity.

Properties of four two-component bacterial transport systems of the cation/proton antiporter-2 (CPA2) family led to suggestions that this CPA2 subset may use a channel rather than an antiport mechanism [see Booth IR, Edwards MD, Gunasekera B, Li C, Miller S (2005) in Bacterial Ion Channels, eds Kubalski A, Martinac B (Am Soc Microbiol, Washington, DC), pp 21-40]. The transporter subset includes the intensively studied glutathione-gated K(+) efflux systems from Escherichia coli, KefGB, and KefFC. KefG and KefF are ancillary proteins. They are peripheral membrane proteins that are encoded in operons with the respective transporter proteins, KefB and KefC, and are required for optimal efflux activity. The other two-component CPA2 transporters of the subset are AmhMT, an NH(4)(+) (K(+)) efflux system from alkaliphilic Bacillus pseudofirmus OF4; and YhaTU, a K(+) efflux system from Bacillus subtilis. Here a K(+)/H(+) antiport capacity was demonstrated for YhaTU, AmhMT, and KefFC in membrane vesicles from antiporter-deficient E. coli KNabc. The apparent K(m) for K(+) was in the low mM range. The peripheral protein was required for YhaU- and KefC-dependent antiport, whereas both AmhT and AmhMT exhibited antiport. KefFC had the broadest range of substrates, using Rb(+) approximately K(+)>Li(+)>Na(+). Glutathione significantly inhibited KefFC-mediated K(+)/H(+) antiport in vesicles. The inhibition was enhanced by NADH, which presumably binds to the KTN/RCK domain of KefC. The antiport mechanism accounts for the H(+) uptake involved in KefFC-mediated electrophile resistance in vivo. Because the physiological substrate of AmhMT in the alkaliphile is NH(4)(+), the results also imply that AmhMT catalyzes NH(4)(+)/H(+) antiport, which would prevent net cytoplasmic H(+) loss during NH(4)(+) efflux.

[Clinical characteristics of urolithiasis with stone analysis conducted over a 26-year period].

OBJECTIVE: Stone analysis is an important examination for treatment and prevention of recurrence in urolithiasis. A twenty-six years clinical study of patient with urinary stone formers performed stone analysis was conducted. MATERIALS AND METHODS: 1,108 stone formers (male 726, female 382) who performed stone analysis from 1977 to 2002 was conducted. Location of the stone, sex, age, treatment and stone analysis was examined in this study. Phase 1 is from 1977 to 1983 mainly performed open surgery, phase 2 is from 1984 to 1992 mainly performed endoscopic surgery, and phase 3 is from 1993 to 2002 mainly performed extracorporeal shock wave lithotripsy (SWL). RESULTS: Analytic numbers per year increased, especially phase 3. In the treatment of upper urinary tract (UUT) stone, open surgery, endoscopic surgery and SWL was carried out 78.4%, 72.8% and 71.4% of all cases in each phase. Many transurethral lithotripsy were performed for lower urinary tract (LUT) stone. The numbers of UUT and LUT stone were 1,007 and 101 cases. The frequency of LUT stone was higher than that found in a nationwide urolithiasis survey carried out in Japan in 1995. The male-female ratio of UUT stone was 2.35:1, 1.74:1 in phase 2 and 3. The frequency of female increased in phase 2 more than that in phase 3. The incidence of calcium oxalate stone was increased, calcium phosphate stone and infectious stone was significantly decreased in UUT and calcium containing stone in LUT was decreased. The average age for incidence of UUT stone rose in man step by step. The frequency in male was significantly higher than that in female under 50's, not significantly higher over 50's in calcium oxalate with calcium phosphate stone former (p = 0.009). CONCLUSION: In the present study, the clinical features were as follows : important urinary stone analysis, high frequency of LUT stone, high frequency in females, tendency to aging, high frequency of calcium containing stone in LUT, resolution of the difference in male and female over 50's in calcium oxalate with calcium phosphate stone former.