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1.
Chronic infection with Helicobacter pylori cagA‐positive strains is causally associated with the development of gastric diseases, most notably gastric cancer. The cagA‐encoded CagA protein, which is injected into gastric epithelial cells by bacterial type IV secretion, undergoes tyrosine phosphorylation at the Glu‐Pro‐Ile‐Tyr‐Ala (EPIYA) segments (EPIYA‐A, EPIYA‐B, EPIYA‐C, and EPIYA‐D), which are present in various numbers and combinations in its C‐terminal polymorphic region, thereby enabling CagA to promiscuously interact with SH2 domain‐containing host cell proteins, including the prooncogenic SH2 domain‐containing protein tyrosine phosphatase 2 (SHP2). Perturbation of host protein functions by aberrant complex formation with CagA has been considered to contribute to the development of gastric cancer. Here we show that SHIP2, an SH2 domain‐containing phosphatidylinositol 5′‐phosphatase, is a hitherto undiscovered CagA‐binding host protein. Similar to SHP2, SHIP2 binds to the Western CagA‐specific EPIYA‐C segment or East Asian CagA‐specific EPIYA‐D segment through the SH2 domain in a tyrosine phosphorylation‐dependent manner. In contrast to the case of SHP2, however, SHIP2 binds more strongly to EPIYA‐C than to EPIYA‐D. Interaction with CagA tethers SHIP2 to the plasma membrane, where it mediates production of phosphatidylinositol 3,4‐diphosphate [PI(3,4)P2]. The CagA‐SHIP2 interaction also potentiates the morphogenetic activity of CagA, which is caused by CagA‐deregulated SHP2. This study indicates that initially delivered CagA interacts with SHIP2 and thereby strengthens H. pylori‐host cell attachment by altering membrane phosphatidylinositol compositions, which potentiates subsequent delivery of CagA that binds to and thereby deregulates the prooncogenic phosphatase SHP2.  相似文献   
2.
Psoriasis is characterized by T‐helper 17 cell‐dominant abnormal immunity, and hyperproliferation and abnormal differentiation of epidermal keratinocytes. Some patients are associated with arthritis. Dietary habits can modulate the pathogenesis of psoriasis. Previous studies in Western countries showed higher body mass indices, higher intake of fat and lower intake of fish or vegetables in psoriatic patients compared with the reference groups. We evaluated dietary habits in adult Japanese psoriatic patients, using a validated brief‐type self‐administered dietary history questionnaire, and compared the results to those of age‐ and sex‐matched healthy controls. The results in psoriatic patients with arthritis were compared with those in the patients without. Japanese psoriatic patients showed higher body mass indices, higher intake of fish/shellfish, pulses, sugar/sweeteners, vitamin B12 and vitamin D, and lower intake of meat, compared with those of healthy controls. The logistic regression analysis showed that psoriasis was associated with high body mass index and low intake of meat. The intake of confection in patients with high Psoriasis Area and Severity Index was higher than that in those with low index. The intake of β‐carotene, vitamin A and green/yellow vegetables in psoriatic patients with arthritis were higher than those in the patients without. The dietary habits in Japanese psoriatic patients are rather different from those in Western patients. This is the first study showing the differences in dietary habits between psoriatic patients with arthritis and those without. Further studies should elucidate the relationships of these results with skin and joint lesions in psoriatic patients.  相似文献   
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BackgroundMajor reasons for long-term care insurance certification in Japan are stroke, dementia, and fracture. These diseases are reported to be associated with calcium intake. This study examined the association between calcium intake and impaired activities of daily living (ADL) using the data from NIPPON DATA90, consisting of representative sample of the Japanese population.MethodsA population-based nested case-control study was performed. A baseline survey was conducted in 1990, followed by ADL surveys of individuals ≥65 years old in 2000. Individuals with impaired ADL and selected age- and sex-matched controls were then identified. We obtained 132 pairs. Calcium intake was energy-adjusted using the residual method. The association between calcium intake and impaired ADL was examined using conditional logistic regression models. To assess the accuracy of the estimates, we conducted bootstrap analyses.ResultsThe adjusted odds ratios (ORs) for impaired ADL compared with the group with a calcium intake of <476 mg/day were 0.72 (95% confidence interval [CI], 0.37–1.40) for the 476–606 mg/day group and 0.44 (95% CI, 0.21–0.94) for the ≥607 mg/day group in 2000 (P for linear trend = 0.03). After the bootstrap analyses, the inverse relationship unchanged (median OR per 100-mg rise in calcium intake, 0.87 [1,000 resamplings]; 95% CI, 0.76–0.97).ConclusionsAfter bootstrap analyses, calcium intake was inversely associated with impaired ADL 10 years after the baseline survey.Key words: bootstrap analyses, calcium intake, impaired activities of daily living, nested case-control study, NIPPON DATA90  相似文献   
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Solar urticaria has unique spectra, such as inhibition and augmentation. The clinical significance of these spectra, especially augmentation, is not well understood. Reported cases of solar urticaria with augmentation spectra are extremely rare in the published English-language work. The purposes of this study were to evaluate the clinical features of solar urticaria with augmentation spectra and to elucidate the mechanisms and clinical importance of the spectra. We experienced 11 cases (five females, six males; mean age, 40.1 years; range, 1–74) of solar urticaria with augmentation spectra from April 2007 to July 2019. Augmentation spectra were UV-B in three cases, UV-A in two, visible light in four, UV-A and UV-B in one, and UV-A and visible light in one. Augmentation spectra were observed before action spectra in four cases, after in six, and before and after in one. Injection of sera irradiated with action spectra and augmentation spectra in vitro induced stronger immediate reactions than those of only action spectrum-irradiated sera in four of five cases. The results of injection tests suggested that augmentation spectra enhance the production of urticaria-forming factor. Clinically, we observed severe urticarial reactions in four cases, including anaphylaxis in three and moderate urticarial reactions in three. These results suggest that augmentation spectra are not as rare as previously thought and that they are associated with the severity of solar urticaria. Therefore, phototesting for both augmentation and action spectra should be performed to provide appropriate guidance for patients with solar urticaria.  相似文献   
7.
We developed a questionnaire to examine the findings of cutaneous arteritis among dermatological specialists experienced in vasculitis as certified by the Committee for guidelines for the management of vasculitis and vascular disorders of the Japanese Dermatological Association. We sent a questionnaire to 12 dermatological facilities identified through the revised Committee for guidelines for the management of vasculitis and vascular disorders of the Japanese Dermatological Association. Retrospective data obtained from 84 patients at the 12 dermatological facilities between 2012 January 2016 December were evaluated. The 84 patients were categorized into two groups, a systemic steroid treatment group (group 1, n = 52) and a no systemic steroid treatment group (group 2, n = 32). C-reactive protein in group 1 patients was significantly higher than that in group 2 patients. Frequency of fever, arthritis, myalgia- and peripheral neuropathy in group 1 was significantly higher than that in group 2. We propose that these symptoms could serve as early markers for the transfer from cutaneous arteritis to systemic polyarteritis nodosa. We further suggest that patients who are subsequently associated with cerebral hemorrhage and infarction, who are originally diagnosed as having cutaneous arteritis, could progress to systemic polyarteritis nodosa. The study demonstrated that it is important for dermatologists to detect these findings early in order to establish an accurate diagnosis and a timely treatment.  相似文献   
8.
Histiocytic sarcoma (HS) is a rare hematopoietic tumor that mainly involves extranodal sites, including the intestinal tract, skin, soft tissues and other organs. It is well known as an aggressive neoplasm that shows a poor response to therapy. However, a subset of patients with resectable disease has shown a favorable outcome with surgical treatment. Primary cutaneous HS is exceedingly rare and, to date, its long-term prognosis has thus not been well described. Here, we highlight two cases of primary cutaneous HS that showed long-term survival. Case 1 was a healthy 47-year-old woman who found a 12-mm tumor on her forehead. Case 2 was a 66-year-old woman, under follow up of a myxoid liposarcoma in her leg, who presented with a 25-mm tumor in her hypothenar eminence. Histologically, the tumors in both cases had a smooth outline with proliferating atypical tumor cells that showed histiocytic differentiation as revealed by immunohistochemistry with antibodies to CD68 (KP-1) and lysozyme in case 1; and CD68, lysozyme and CD163 in case 2. Tumor cells in case 1 had a monotonous appearance. After complete resection, cases 1 and 2 have survived for 10 and 4 years, respectively, without recurrence. To date, such patients are relatively long follow-up cases of survival from HS and highlight how a clear outline of the primary cutaneous HS tumor may be associated with its resectability and be an important factor in the assessment of its curability.  相似文献   
9.
In July 2017, Japan’s Ministry of Health, Labor and Welfare issued a marketing authorization valid throughout Japan for N-(2,6-dimethylphenyl)-N-(2-{[4-(1,2,4-oxadiazol-3-yl)phenyl]amino}-2-oxoethyl)-1,1-dioxothiane-4-carboxamide (amenamevir) for the first time worldwide. The decision was based on the favorable opinion of the Pharmaceuticals and Medical Device Agency (PMDA) recommending a marketing authorization of amenamevir for treatment of herpes zoster (HZ). Amenamevir has a different action mechanism from previously approved synthetic nucleoside compounds for the treatment of HZ including acyclovir, valacyclovir and famciclovir. The usual adult dose is 400 mg amenamevir p.o. once daily for 7 days. The benefit is its ability to cure HZ as well as preventing postherpetic neuralgia. The most common side-effects are increase of urine N-acetyl-β-D-glucosaminidase and α1-microglobulin levels. However, based on the detailed evaluation of the submitted clinical studies, there seems to be no serious safety concerns about amenamevir regarding the kidney of both renally normal and impaired patients. The objective of this article is to summarize the scientific review of the application. The detailed scientific assessment report and product information, including the summary of product characteristics, are available on the PMDA website ( www.pmda.go.jp/PmdaSearch/iyakuSearch/ ).  相似文献   
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