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11.
Most opsins selectively bind 11-cis retinal as a chromophore to form a photosensitive pigment, which underlies various physiological functions, such as vision and circadian photoentrainment. Recently, opsin 3 (Opn3), originally called encephalopsin or panopsin, and its homologs were identified in various tissues including brain, eye, and liver in both vertebrates and invertebrates, including human. Because Opn3s are mainly expressed in tissues that are not considered to contain sufficient amounts of 11-cis retinal to form pigments, the photopigment formation ability of Opn3 has been of interest. Here, we report the successful expression of Opn3 homologs, pufferfish teleost multiple tissue opsin (PufTMT) and mosquito Opn3 (MosOpn3) and show that these proteins formed functional photopigments with 11-cis and 9-cis retinals. The PufTMT- and MosOpn3-based pigments have absorption maxima in the blue-to-green region and exhibit a bistable nature. These Opn3 homolog-based pigments activate Gi-type and Go-type G proteins light dependently, indicating that they potentially serve as light-sensitive Gi/Go-coupled receptors. We also demonstrated that mammalian cultured cells transfected with the MosOpn3 or PufTMT became light sensitive without the addition of 11-cis retinal and the photosensitivity retained after the continuous light exposure, showing a reusable pigment formation with retinal endogenously contained in culture medium. Interestingly, we found that the MosOpn3 also acts as a light sensor when constituted with 13-cis retinal, a ubiquitously present retinal isomer. Our findings suggest that homologs of vertebrate Opn3 might function as photoreceptors in various tissues; furthermore, these Opn3s, particularly the mosquito homolog, could provide a promising optogenetic tool for regulating cAMP-related G protein-coupled receptor signalings.  相似文献   
12.
BACKGROUND: Cyclosporine (CsA), Mycophenolate mofetil (MMF) and prednisolone (PSL) are widely used for the prevention of acute rejection after heart transplantation. Recently, the serum concentration - time curves (AUC) of CsA and MMF have been demonstrated to be precise predictors of acute rejection. METHODS AND RESULTS: Fourteen heart transplant patients were treated concomitantly with CsA, MMF, and PSL between May 1999 and November 2005 at the National Cardiovascular Center and of them 3 had acute rejection episodes [International Society for Heart & Lung Transplantation grade 3a]. Two patients (man in his 30 s; woman in her 40 s) had acute rejection with a mycophenolic acid (MPA) AUC(0-12 h) <30 microg x h x ml(-1) and low CsA AUC (AUC(0-4 h); 2,408 ng x h x ml-1, 1,735 ng x h x ml-1). However, 1 patient (man in his 30 s) with a high CsA AUC(0-4 h) (4,019 ng x h x ml-1) did not develop cardiac allograft rejection even if the MMF was temporarily stopped. These 3 patients were investigated to evaluate the relationship between acute rejection and pharmacokinetic parameters, including the CsA C0, C2, AUC(0-4 h) and MPA AUC(0-12 h). CONCLUSIONS: The findings suggest that a high CsA AUC(0-4 h) may prevent rejection of a cardiac allograft, even if MMF is stopped or drastically reduced.  相似文献   
13.
BACKGROUND: Serum uric acid (SUA) is related not only to an increased risk of gout, but also to an increased risk of cardiovascular diseases. However, real age-related changes in SUA remain unknown. METHODS: Longitudinal population-based study of epidemiological follow-up data of SUA, body mass index (BMI), and alcohol intake was conducted at a health examination center between 1989 and 1998. The subjects were 80,506 Japanese office workers or their families (50,157 men and 30,349 women) with an average age of 44.5 years for the men and 43.7 years for the women. RESULTS: SUA increased with age in all birth cohorts examined in men, and in women except for the youngest birth cohort (1960-1969). BMI and alcohol consumption positively contributed to the longitudinal changes of SUA. However, SUA also increased with age in the model controlled for BMI and alcohol consumption. There were birth cohort effects of SUA; at most ages, there were higher SUA levels in younger cohorts in men and lower SUA levels in younger cohorts in women, respectively. CONCLUSIONS: SUA levels in men and women increased with advancing age, despite changes in drinking and in the BMI. There are birth cohort effects for SUA levels in the Japanese population.  相似文献   
14.
BACKGROUND/AIMS: The aim of this study was to clarify the need for measuring of PIVKA-II (protein induced by vitamin K absence or antagonist-II) and alpha-fetoprotein as the prognostic indicator for patients after hepatic resection for hepatocellular carcinoma, and as the monitoring modality for early detection of recurrence after hepatic resection. METHODOLOGY: One hundred and thirty-one patients who underwent planned liver resections for hepatocellular carcinoma were studied. RESULTS: The survival rates in patients positive for preoperative tumor markers were significantly lower than in those in the negative patients. The first modality leading to the diagnosis of recurrence was measurement of alpha-fetoprotein and/or PIVKA-II in 25 cases (55.6%). Almost all patients (96.6%) with positive preoperative alpha-fetoprotein and recurrence had elevated alpha-fetoprotein again when recurrence was found. CONCLUSIONS: Preoperative PIVKA-II and/or alpha-fetoprotein levels can predict postoperative prognosis. Measurement of these markers is useful in monitoring recurrence. For following up patients with alpha-fetoprotein-producing tumors, alpha-fetoprotein monitoring only is sufficient to detect recurrence.  相似文献   
15.
It is of concern that women are more likely to undergo fewer diagnostic tests and receive less treatment for acute myocardial infarction (AMI) than men. However, it is still unclear whether gender differences exist according to age groups. Therefore, we studied the influence of gender on the delivery of cardiac management according to two age groups (< 65, >or= 65) in Japan. Data from the Tokai Acute Myocardial Infarction Study (TAMIS) sample were used. This is a retrospective study of all consecutive patients admitted to the 13 acute care hospitals in the Tokai region of Japan, which includes Aichi and Shizuoka Prefectures, with a diagnosis of AMI from 1995 to 1997. A total of 143 younger women, 822 younger men, 391 older women, and 611 older men were included. Information concerning patient demographics, in-hospital course, comorbid conditions, electrocardiography (ECG), ultrasound-echocardiography (UCG), treadmill test (TMT), coronary angiography (CAG), percutaneous transluminal coronary angioplasty (PTCA), coronary artery bypass graft (CABG), intra-aortic balloon pump (IABP), mechanical ventilation, and in-hospital or discharge medication (thrombolytics, vasopressors, aspirin, beta-blockers, angiotensin-converting enzyme (ACE) inhibitors, calcium antagonists, nitrates) were collected. Among the young, after controlling for these baseline variables, women were significantly less likely to undergo PTCA compared to men (OR, 0.54, 95%CI, 0.35-0.82). After controlling for these baseline variables, only lipid-lowering therapy tended to be more frequent in women than in men among the elderly (OR, 2.79, 95%CI, 1.47-2.58). The findings suggest that younger women with AMI are less likely than younger men to undergo PTCA, and that older women with AMI are more likely to receive lipid-lowering therapy.  相似文献   
16.
We report here the crystal structure of the RuvB motor protein from Thermus thermophilus HB8, which drives branch migration of the Holliday junction during homologous recombination. RuvB has a crescent-like architecture consisting of three consecutive domains, the first two of which are involved in ATP binding and hydrolysis. DNA is likely to interact with a large basic cleft, which encompasses the ATP-binding pocket and domain boundaries, whereas the junction-recognition protein RuvA may bind a flexible beta-hairpin protruding from the N-terminal domain. The structures of two subunits, related by a noncrystallographic pseudo-2-fold axis, imply that conformational changes of motor protein coupled with ATP hydrolysis may reflect motility essential for its translocation around double-stranded DNA.  相似文献   
17.
Along with the increased use of other laparoscopic procedures, laparoscopic inguinal hernia repair has become widely used because of its minimally invasive nature. Here, we report a case of 66‐year‐old man who underwent transabdominal preperitoneal laparoscopic hernioplasty and developed hemorrhagic shock on postoperative day 1. CT showed postoperative venous hemorrhage from the retropubic space. Successful hemostasis of the massive hemorrhage was achieved laparoscopically. The origin of the hemorrhage was assumed to be the corona mortis vein, which was slightly injured during the operation. Despite the rarity of this complication, surgeons must be aware of the need to carefully dissect and fix the mesh in the retropubic space to avoid injuring the corona mortis. Laparoscopic hemostasis may be an effective alternative to the open approach.  相似文献   
18.
At present, vancomycin (VCM) and metronidazole (MNZ) are used for the first-line standard treatment of Clostridioides difficile infection (CDI). However, their differential use has not been sufficiently investigated. In this study, a meta-analysis on differences in the efficacy for CDI between VCM and MNZ was performed. Reports of randomized controlled studies using VCM or MNZ to treat CDI were surveyed. Meta-analysis was performed using the Mantel-Haenszel method and random-effects model, and the risk ratio and 95% confidence interval were calculated. Excluding overlapping reports, 1043 reports were extracted and 5 randomized controlled studies were extracted. There was no difference in therapeutic effects for CDI between VCM and MNZ (RR = 1.08, 95% CI (0.99–1.17), p = 0.09, I2 = 37%). On subgroup analysis by the severity, there was no difference in the clinical effects for CDI between VCM and MNZ in non-severe cases (risk ratio: 1.09, 95% confidence interval: 1.00–1.19, p = 0.06), but the clinical effects of VCM were significantly higher than those of MNZ in severe cases (risk ratio: 1.19, 95% confidence interval: 1.02–1.39, p = 0.03). No significant difference was noted in the recurrence rate, incidence of adverse event, time to exhibit therapeutic effects, or judgment of the bacteriological effects. As the therapeutic effects of VCM were superior in severe CDI cases, VCM should be considered first in severe cases.  相似文献   
19.
In this paper, we discuss the synthesis of imido-substituted chlorotriazines and demonstrate their use in dehydrative condensation reactions. Chemoselective amide-forming reactions of amino alcohols using succinimido-substituted chlorotriazine (2A) proceeded smoothly. Occasionally, nonselectivity was problematic during the synthesis of hydroxy-substituted amides. Moreover, it was noteworthy that this method was applicable to hydroxy-substituted carboxylic acids that could have formed a lactone or an ester during the carboxylic acid activation step. The imido-substituted chlorotriazine (2A) was superior to the amido-substituted chlorotriazine and 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) in terms of reaction rates and yields.

In this paper, we discuss the synthesis of imido-substituted chlorotriazines and demonstrate their use in dehydrative condensation reactions.  相似文献   
20.
An 84-year-old man was admitted with epigastralgia. Computed tomography showed contrast-enhanced wall thickness in the cystic duct. An endoscopic examination revealed short irregular stricture in the cystic duct, and per-oral cholangioscopy revealed a reddish papillary tumor at the stricture site. Surgical resection revealed high-grade biliary intraepithelial neoplasia (BilIN) at the stricture site of the cystic duct. To our knowledge, this is the first case of a solitary high-grade BilIN epithelium in the cystic duct detected by per-oral cholangioscopy.  相似文献   
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