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81.
To examine whether alpha and beta tubulin are glycoproteins, we used a pyridylamino labeling method and a monoclonal antibody, SG3-1, raised against NeuAcalpha2-3Gal structure. Alpha and beta tubulin from both pig brain and HeLa cells were positive for the SG3-1 antibody by immunoblot assay. Sialidase treatment reduced the reactivity of the SG3-1 antibody to alpha and beta tubulin molecules. N-linked oligosaccharide analysis also showed that alpha and beta tubulin are glycosylated. Moreover, immunofluorescence analysis showed that the filamentous structure recognized by the SG3-1 antibody was overlapped with microtubules, especially in the vicinity of the nucleus. These results indicate that alpha and beta tubulin are glycosylated with sialyloligosaccharides.  相似文献   
82.
A microorganism was isolated from the air of a patient-room and classified in the genus Oospora. This microorganism was cultured on a malt extract medium, and the mycellium was separated from the culture filtrate. A new compound (O-1), m.p. 129°C, C11H10O3, and eburicoic acid, m.p. 290°C, C31H50O3 were obtained from the dried mycellium. Another new compound (O-2), m.p. 176°C, C11H8O5 was obtained from the culture filtrate.  相似文献   
83.
To develop a drug delivery system for acute hepatic injury, we prepared Z-Asp, a general caspase inhibitor, encapsulated in poly (DL-lactic-co-glycolic acid) (50:50) (mol/mol) nanoparticles bearing poly-(N-p-vinylbenzyl-O--d-galactopyranosyl-[1-4]-d-gluconamide) (PVLA) on their surface. These nanoparticles specifically interacted with the primary cultured hepatocytes via the asialoglycoprotein receptors on surface and effectively inhibited the fulminant hepatic cell death induced by anti-mouse Fas antibody while these particles did not affect the cell death of an asialoglycoprotein receptor null cell line, A20. These nanoparticles are thus a promising therapy for acute liver injury.  相似文献   
84.

Background

The World Health Organization has called for global and regional assessments of the burden of hepatitis C (HCV) along with country-specific patient profiles to better inform healthcare policy. The present investigated the characteristics and burden of patients reporting a diagnosis of HCV infection in the US, France, Germany, Italy, Spain, the UK, urban China, and Japan using a consistent methodology of patient-reported surveys.

Methods

The 2010 5EU (N = 57,805), 2009 US (N = 75,000), 2008/2009 Japan (N = 37,683), and 2009/2010 urban China (N = 33,261) waves of the National Health and Wellness Survey were used as the data source. Within each country, patients with a self-reported diagnosis of HCV were compared with those who did not report a diagnosis of HCV on sociodemographics, health behaviors, comorbidities, and health outcomes (e.g., Short Form-12v2). The effect of HCV was examined using regression analysis applying sampling weights.

Results

The prevalence of HCV ranged from 0.26% (China) to 1.42% (Italy). Patients in Japan and Italy (61.60 and 61.02 years, respectively) were the oldest, while patients in the US were the most likely to be obese (39.31%) and have concomitant anxiety (38.43%) and depression (46.05%) compared with other countries. Pooling countries and adjusting for sociodemographics, health behaviors, and comorbidities, HCV was associated with significantly lower physical component summary scores (b = −2.51) and health utilities (b = −0.04) and greater overall work impairment (b = 8.79), physician visits (b = 2.91), and emergency department visits (b = 0.30) (all p<.05). The effects on health status were strongest in the US and UK while the effects on healthcare resource use were strongest in Japan.

Conclusions

HCV was associated with a significant humanistic and economic burden. These results suggest that the manifestation of the HCV burden, and the profile of the patients themselves, varied dramatically by country. Successful disease management should be cognizant of region-specific unmet needs.  相似文献   
85.
Summary Whole cells of Kluyvera citrophila were immobilized in polyacrylamide gel. The penicillin acylase activity of immobilized whole cells was 60%–70% of native cells. When the immobilized cells were continuously cultivated for 40 h in an aerated fermentor containing peptone medium and were treated with alkali in order to remove -lactamase activity, the immobilized cells produced ampicillin up to 4.4 times faster than noncultivated cells.Ampicillin production was investigated in a column system using these cultivated immobilized whole cells. The cultivated immobilized cells showed excellent performance in continuous ampicillin production.  相似文献   
86.
Translation arrest leads to an endonucleolytic cleavage of mRNA that is termed no-go decay (NGD). It has been reported that the Dom34:Hbs1 complex stimulates this endonucleolytic cleavage of mRNA induced by translation arrest in vivo and dissociates subunits of a stalled ribosome in vitro. Here we report that Dom34:Hbs1 dissociates the subunits of a ribosome that is stalled at the 3' end of mRNA in vivo, and has a crucial role in both NGD and nonstop decay. Dom34:Hbs1-mediated dissociation of a ribosome that is stalled at the 3' end of mRNA is required for degradation of a 5'-NGD intermediate. Dom34:Hbs1 facilitates the decay of nonstop mRNAs from the 3' end by exosomes and is required for the complete degradation of nonstop mRNA decay intermediates. We propose that Dom34:Hbs1 stimulates degradation of the 5'-NGD intermediate and of nonstop mRNA by dissociating the ribosome that is stalled at the 3' end of the mRNA.  相似文献   
87.
Three new water-soluble chlorin derivatives 3, 5 and 8 for potential use as photosensitizers in photodynamic therapy (PDT) for cancer were synthesized from photoprotoporphyrin IX dimethyl ester (1). The in vivo biodistribution and clearance of chlorin derivatives 3, 5 and 8 were investigated in tumor-bearing mice. Iminodiacetic acid derivative 8 showed the greatest tumor-selective accumulation among the new chlorin derivatives with maximum accumulation in tumor tissue at 3 h after intravenous injection and rapid clearance from normal tissues within 24 h after injection. The in vivo therapeutic efficacy of PDT using 8 was evaluated by measuring tumor growth rates in tumor-bearing mice with 660 nm light-emitting diode irradiation at 3 h after injection of 8. Tumor growth was significantly inhibited by PDT using 8. These results indicate that iminodiacetic acid derivative 8 is useful as a new photosensitizer to overcome the disadvantages of photosensitizers that are currently in clinical use.  相似文献   
88.
The high affinity IgE Fc receptor (FcεRI) β chain is well implicated as a signal amplifier through the immunoreceptor tyrosine-based activation motif (ITAM) in its C-terminal intracellular region. Our previous study, however, demonstrated that mutation in all of the three tyrosine residues within the FcεRIβ ITAM did not impair FcεRI-induced cytokine production, suggesting a possible functional region other than the ITAM. To investigate the ITAM-independent mechanism by which FcεRIβ regulates FcεRI-induced cytokine production, mouse mast cells expressing various FcεRIβ mutants were generated. We observed that truncation of the FcεRIβ C-terminus downstream of the ITAM resulted in a considerable decrease in FcεRI-induced IL-6 production but not degranulation. Furthermore, mutagenesis of a single C-terminal aspartic acid (D234) to alanine (β-D234A) also significantly impaired IL-6 production. In addition, the similarity between the circular dichroism (CD) spectra of the wild type and β-D234A suggests that the secondary structure of the FcεRIβ C-terminus was not affected by the D234A mutation. Consistently, we did not observe any effect of this mutation on FcεRI-induced tyrosine phosphorylation of FcεRIβ. These observations strongly suggest a novel signaling pathway mediated by the cytoplasmic tail downstream of the FcεRIβ ITAM.  相似文献   
89.
Although congenital scoliosis is defined as a genetic disease characterized by a congenital and abnormal curvature of the spinal vertebrae, our knowledge of the genetic underpinnings of the disease is insufficient. We herein show that the downregulation of the retinol-retinoic acid metabolism pathway is involved in the pathogenesis of congenital scoliosis. By analyzing DNA microarray data, we found that the expression levels of genes associated with the retinol metabolism pathway were decreased in the lumbar spine of Ishibashi rats (IS), a rat model of congenital kyphoscoliosis. The expression of Adh1 and Aldh1a2 (alcohol dehydrogenase), two enzymes that convert retinol to retinoic acid in this pathway, were decreased at both the gene and protein levels. Rarα, a receptor of retinoic acid and bone morphogenetic protein 2, which play a central role in bone formation and are located downstream of this pathway, were also downregulated. Interestingly, the serum retinol levels of IS rats were higher than those of wild-type control rats. These results indicate that the adequate conversion from retinol to retinoic acid is extremely important in the regulation of normal bone formation and it may also be a key factor for understanding the pathogenesis of congenital scoliosis.  相似文献   
90.
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