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901.
Keiichi?Masaki Fumitaka?SuzukiEmail author Tasuku?Hara Yusuke?Kawamura Hitomi?Sezaki Tetsuya?Hosaka Norio?Akuta Masahiro?Kobayashi Satoshi?Saitoh Yoshiyuki?Suzuki Yasuji?Arase Kenji?Ikeda Mariko?Kobayashi Hiromitsu?Kumada 《Virology journal》2015,12(1):225
Background
There is no information on the long-term effects of peginterferon (PEG-IFN) alfa-2a therapy for chronic hepatitis B (CHB) in Japan. This double-blind, randomized trial investigated the efficacy of PEG-IFN therapy.Methods
We analyzed 22 Japanese patients with CHB (hepatitis B e antigen [HBeAg]-positive: 17, HBeAg-negative: 5) treated with PEG-IFN alfa-2a and followed-up posttreatment for 5 years. Responders represented patients who showed persistent normalization of alanine transferase (ALT) levels, HBeAg clearance, and low hepatitis B virus (HBV) DNA levels (HBeAg-positive patient; <5 log copies/mL, HBeAg-negative patient; <4.3 log copies/mL) at end of treatment, and at 1, 2, 3, 4 and 5 years posttreatment. In addition, baseline HBeAg-positive patients who showed sustained normalization of ALT level, HBeAg clearance, and low HBV DNA level for more than 6 months until at 1, 2, 3, 4, and 5 years after completion of PEG-IFN were also classified as “triple responders” and the proportion of triple responders relative to all patients was termed the “triple response rate”.Results
The response rates among HBeAg-positive patients were 13 %, 25 %, 14 %, 21 % and 21 % at end of treatment, and at 1, 2, 3, 4, and 5 years, respectively. The response rate tended to be higher in patients treated for 48 than 24 weeks. The respective response rates among HBeAg-negative patients were 0 %, 20 %, 20 %, 20 % and 25 %. During the treatment period, hepatitis B surface antigen (HBsAg) clearance at 3.5 years was noted in one patient, who was 37-year-old, male, had genotype C and received PEG-IFN alfa-2a at 90 μg for 48 weeks.Conclusion
At 5 years after completion of PEG-IFN, the triple response rate in HBeAg-positive patients and combined response rate in HBeAg-negative patients were 21 % (3/14) and 25 % (1/4), respectively. The triple response was seen in three patients who had all been treated with PEG-IFN for 48 weeks.902.
Mating rates and the prevalence of male‐killing Spiroplasma in Harmonia axyridis (Coleoptera: Coccinellidae)
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Maternally inherited bacteria that kill male but not female hosts during embryogenesis have been widely reported in invertebrates. Harmonia axyridis is one of the species infected by male‐killing Spiroplasma. The presence of male‐killers in host populations can lead to the occurrence of extremely female‐biased sex ratios. Furthermore, infected females may have fewer chances to mate if males can discriminate between infected and uninfected females and prefer the latter. Although there have been many investigations of male‐killer infection rates in H. axyridis, little is known about the influence of host mating on male‐killer infection dynamics. We investigated copulation rates and changes in infection frequency in a wild population of H. axyridis in western Japan. Almost all infected females collected each year laid fertilized eggs and had therefore mated. Mean infection rates of females collected each year were 13% in 2003, 15% in 2012 and 23% in 2013. Statistical analysis showed that neither the copulation rate nor the infection rate differed significantly among years. These results suggest that the infection rate of H. axyridis with male‐killing Spiroplasma is kept approximately constant and that there is no difference in the chance of mating with infected and uninfected females. 相似文献
903.
Nishiura H Kido M Aoki N Iwamoto S Maruoka R Ikeda A Chiba T Ziegler SF Watanabe N 《Journal of immunology (Baltimore, Md. : 1950)》2012,188(1):190-197
Thymic stromal lymphopoietin (TSLP), mainly produced by epithelial cells, activates a variety of cell types, including dendritic cells, mast cells, T cells, and B cells. It is involved in the pathogenesis of allergic inflammation in the lung, skin, and gastrointestinal tract. In addition, TSLP promotes Th2-type intestinal immunity against helminth infection and regulates Th1-type inflammation in a mouse model of colitis, suggesting that it plays crucial roles in intestinal immune homeostasis. Although autoimmune gastritis (AIG), mediated by inflammatory Th1 responses, develops in the gastric mucosa, it is not clear whether TSLP is involved in regulating these responses in AIG. The aim of this study was to examine the roles of TSLP in the development of AIG. Because BALB/c mice thymectomized 3 d after birth (NTx mice) develop AIG, we used this model to test the role of TSLP in the development of AIG. We found that in AIG-bearing mice, TSLP was expressed in the inflamed stomach and that the serum anti-parietal cell Ab levels in neonatal thymectomized TSLPR-deficient mice (NTx-TSLPR(-/-) mice) were significantly elevated over those in NTx-TSLPR(+/+) mice. In addition, NTx-TSLPR(-/-) mice exhibited an earlier onset of AIG than that observed in NTx-TSLPR(+/+) mice. The rapid development of AIG in NTx-TSLPR(-/-) mice resulted in more aggressive CD4(+) T cell infiltration and more severe loss of parietal and chief cells in the progression phase of AIG, accompanied by enhanced production of IL-12/23p40 and IFN-γ. Taken together, these data suggested that TSLP negatively regulates the development of AIG. 相似文献
904.
Fujii Y Hirayama T Ohtake H Ono N Inoue T Sakurai T Takayama T Matsumoto K Tsukahara N Hidano S Harima N Nakazawa K Igarashi Y Goitsuka R 《Journal of immunology (Baltimore, Md. : 1950)》2012,188(1):206-215
Sphingosine 1-phosphate (S1P) regulates lymphocyte trafficking through the type 1 sphingosine 1-phosphate receptor (S1P(1)) and participates in many pathological conditions, including autoimmune diseases. We developed a novel S1P(1)-selective antagonist, TASP0277308, which is structurally unrelated to S1P. This antagonist competitively inhibited S1P-induced cellular responses, such as chemotaxis and receptor internalization. Furthermore, differing from previously reported S1P(1) antagonists, TASP0277308 demonstrated in vivo activities to induce lymphopenia, a block in T cell egress from the thymus, displacement of marginal zone B cells, and upregulation of CD69 expression on both T and B cells, all of which recapitulate phenotypes of S1P(1)-deficient lymphocytes. In a mouse collagen-induced arthritis model, TASP0277308 significantly suppressed the development of arthritis, even after the onset of disease. These findings provide the first chemical evidence to our knowledge that S1P(1) antagonism is responsible for immunosuppression in the treatment of autoimmune diseases and also resolve the discrepancies between genetic and chemical studies on the functions of S1P(1) in lymphocytes. 相似文献
905.
J. Neurochem. (2012) 122, 883-890. ABSTRACT: Amyloid β-protein (Aβ) and α-synuclein (αS) are the primary components of amyloid plaques and Lewy bodies (LBs), respectively. Previous in vitro and in vivo studies have suggested that interactions between Aβ and αS are involved in the pathogenesis of Alzheimer's disease and LB diseases. However, the seeding effects of their aggregates on their aggregation pathways are not completely clear. To investigate the cross-seeding effects of Aβ and αS, we examined how sonicated fibrils or cross-linked oligomers of Aβ40, Aβ42, and αS affected their aggregation pathways using thioflavin T(S) assay and electron microscopy. Fibrils and oligomers of Aβ40, Aβ42, and αS acted as seeds, and affected the aggregation pathways within and among species. The seeding effects of αS fibrils were higher than those of Aβ40 and Aβ42 fibrils in the Aβ40 and Aβ42 aggregation pathways, respectively. We showed that Aβ and αS acted as seeds and affected each other's aggregation pathways in vitro, which may contribute to our understanding of the molecular mechanisms of interactions between Alzheimer's disease and LB diseases pathologies. 相似文献
906.
Kanzawa N Shimozawa N Wanders RJ Ikeda K Murakami Y Waterham HR Mukai S Fujita M Maeda Y Taguchi R Fujiki Y Kinoshita T 《Journal of lipid research》2012,53(4):653-663
Many cell surface proteins in mammalian cells are anchored to the plasma membrane via glycosylphosphatidylinositol (GPI). The predominant form of mammalian GPI contains 1-alkyl-2-acyl phosphatidylinositol (PI), which is generated by lipid remodeling from diacyl PI. The conversion of diacyl PI to 1-alkyl-2-acyl PI occurs in the ER at the third intermediate in the GPI biosynthetic pathway. This lipid remodeling requires the alkyl-phospholipid biosynthetic pathway in peroxisome. Indeed, cells defective in dihydroxyacetone phosphate acyltransferase (DHAP-AT) or alkyl-DHAP synthase express only the diacyl form of GPI-anchored proteins. A defect in the alkyl-phospholipid biosynthetic pathway causes a peroxisomal disorder, rhizomelic chondrodysplasia punctata (RCDP), and defective biogenesis of peroxisomes causes Zellweger syndrome, both of which are lethal genetic diseases with multiple clinical phenotypes such as psychomotor defects, mental retardation, and skeletal abnormalities. Here, we report that GPI lipid remodeling is defective in cells from patients with Zellweger syndrome having mutations in the peroxisomal biogenesis factors PEX5, PEX16, and PEX19 and in cells from patients with RCDP types 1, 2, and 3 caused by mutations in PEX7, DHAP-AT, and alkyl-DHAP synthase, respectively. Absence of the 1-alkyl-2-acyl form of GPI-anchored proteins might account for some of the complex phenotypes of these two major peroxisomal disorders. 相似文献
907.
Sasakura Y Kanda M Ikeda T Horie T Kawai N Ogura Y Yoshida R Hozumi A Satoh N Fujiwara S 《Development (Cambridge, England)》2012,139(12):2156-2160
Retinoic acid (RA)-mediated expression of the homeobox gene Hox1 is a hallmark of the chordate central nervous system (CNS). It has been suggested that the RA-Hox1 network also functions in the epidermal ectoderm of chordates. Here, we show that in the urochordate ascidian Ciona intestinalis, RA-Hox1 in the epidermal ectoderm is necessary for formation of the atrial siphon placode (ASP), a structure homologous to the vertebrate otic placode. Loss of Hox1 function resulted in loss of the ASP, which could be rescued by expressing Hox1 in the epidermis. As previous studies showed that RA directly upregulates Hox1 in the epidermis of Ciona larvae, we also examined the role of RA in ASP formation. We showed that abolishment of RA resulted in loss of the ASP, which could be rescued by forced expression of Hox1 in the epidermis. Our results suggest that RA-Hox1 in the epidermal ectoderm played a key role in the acquisition of the otic placode during chordate evolution. 相似文献
908.
Urbahns K Yura T Gupta JB Tajimi M Fujishima H Masuda T Yamamoto N Ikegami Y Marumo M Yasoshima K Yoshida N Moriwaki T Madge D Chan F Mogi M 《Bioorganic & medicinal chemistry letters》2012,22(10):3408-3411
Starting from a naphthol-based lead series with low oral bioavailability, we have identified potent TRPV1 antagonists with oral bioavailability in rats. These compounds emerged from SAR studies aimed at replacing the lead's phenol structure whilst maintaining potency. Compound rac-6a is an orally available TRPV1 antagonist with single-digit nanomolar activity. The enantiomers show a low eudismic ratio at the receptor level. 相似文献
909.
Higashi TL Ikeda M Tanaka H Nakagawa T Bando M Shirahige K Kubota Y Takisawa H Masukata H Takahashi TS 《Current biology : CB》2012,22(11):977-988
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910.
Minehira D Takeda D Urata H Kato A Adachi I Wang X Matsuya Y Sugimoto K Takemura M Endo S Matsunaga T Hara A Koseki J Narukawa K Hirono S Toyooka N 《Bioorganic & medicinal chemistry》2012,20(1):356-367
New substituted (1-thioxo-1,2,3,4-tetrahydro-β-carbolin-9-yl)acetic acids were designed as the inhibitor of AKR1B1 based upon the structure of rhetsinine, a minor alkaloidal component of Evodia rutaecarpa, and twenty derivatives were synthesized and evaluated. The most active compound of the series was (2-benzyl-6-methoxy-1-thioxo-1,2,3,4-tetrahydro-β-carbolin-9-yl)acetic acid (7m), which showed comparable inhibitory activity for AKR1B1 (IC(50)=0.15μM) with clinically used epalrestat (IC(50)=0.1μM). In the view of activity and selectivity, the most potent compound was (2-benzyl-6-carboxy-1-thioxo-1,2,3,4-tetrahydro-β-carbolin-9-yl)acetic acid (7t), which showed strong inhibitory effect (IC(50)=0.17μM) and very high selectivity for AKR1B1 against AKR1A1 (311:1) and AKR1B10 (253:1) compared with epalrestat. 相似文献