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941.
Viral myocarditis presents with various symptoms, including fatal arrhythmia and cardiogenic shock, and may develop chronic myocarditis and dilated cardiomyopathy in some patients. We report here a case of viral myocarditis with liver dysfunction and pancreatitis. A 63-year-old man was admitted to our hospital with dyspnea. The initial investigation showed pulmonary congestion, complete atrioventricular block, left ventricular dysfunction, elevated serum troponin I, and elevated liver enzyme levels. He developed pancreatitis five days after admission. Further investigation revealed a high antibody titer against coxsackievirus A4. The patient’s left ventricular dysfunction, pancreatitis, and liver dysfunction had resolved by day 14, but his troponin I levels remained high, and an endomyocardial biopsy showed T-lymphocyte infiltration of the myocardium, confirming acute myocarditis. The patient underwent radical low anterior resection five weeks after admission for advanced rectal cancer found incidentally. His serum troponin I and plasma brain natriuretic peptide levels normalized six months after admission. He has now been followed-up for two years, and his left ventricular ejection fraction is stable. This is the first report of an adult with myocarditis and pancreatitis attributed to coxsackievirus A4. Combined myocarditis and pancreatitis arising from coxsackievirus infection is rare. This patient’s clinical course suggests that changes in his immune response associated with his rectal cancer contributed to the amelioration of his viral myocarditis.  相似文献   
942.
Although hyperventilation syndrome generally carries a good prognosis, it is associated with the risk of developing severe symptoms, such as post-hyperventilation apnea with hypoxemia and loss of consciousness. We experienced a patient who suffered from post-hyperventilation apnea. A 17-year-old female who suffered from hyperventilation syndrome for several years developed post-hyperventilation apnea after treatment using the paper bag rebreathing method and sedative administration during a dental procedure. We subsequently successfully provided her with monitored anesthesia care with propofol. Monitored anesthesia care with propofol may be effective for the general management of patients who have severe hyperventilation attacks and post-hyperventilation apnea. This case demonstrates that appropriate emergency treatment should be available for patients with hyperventilation attacks who are at risk of developing post-hyperventilation apnea associated with hypoxemia and loss of consciousness.  相似文献   
943.
The phase of the cell cycle can determine whether a cancer cell can respond to a given drug. We report here on the results of monitoring of real-time cell cycle dynamics of cancer cells throughout a live tumor intravitally using a fluorescence ubiquitination cell cycle indicator (FUCCI) before, during, and after chemotherapy. In nascent tumors in nude mice, approximately 30% of the cells in the center of the tumor are in G0/G1 and 70% in S/G2/M. In contrast, approximately 90% of cancer cells in the center and 80% of total cells of an established tumor are in G0/G1 phase. Similarly, approximately 75% of cancer cells far from (>100 µm) tumor blood vessels of an established tumor are in G0/G1. Longitudinal real-time imaging demonstrated that cytotoxic agents killed only proliferating cancer cells at the surface and, in contrast, had little effect on quiescent cancer cells, which are the vast majority of an established tumor. Moreover, resistant quiescent cancer cells restarted cycling after the cessation of chemotherapy. Our results suggest why most drugs currently in clinical use, which target cancer cells in S/G2/M, are mostly ineffective on solid tumors. The results also suggest that drugs that target quiescent cancer cells are urgently needed.  相似文献   
944.

Background

The Global Burden of Diseases Study 2010 reported that hypertension is worldwide the leading risk factor for cardiovascular disease, causing 9.4 million deaths annually. We examined to what extent self-measurement of home blood pressure (HBP) refines risk stratification across increasing categories of conventional blood pressure (CBP).

Methods and Findings

This meta-analysis included 5,008 individuals randomly recruited from five populations (56.6% women; mean age, 57.1 y). All were not treated with antihypertensive drugs. In multivariable analyses, hazard ratios (HRs) associated with 10-mm Hg increases in systolic HBP were computed across CBP categories, using the following systolic/diastolic CBP thresholds (in mm Hg): optimal, <120/<80; normal, 120–129/80–84; high-normal, 130–139/85–89; mild hypertension, 140–159/90–99; and severe hypertension, ≥160/≥100.Over 8.3 y, 522 participants died, and 414, 225, and 194 had cardiovascular, cardiac, and cerebrovascular events, respectively. In participants with optimal or normal CBP, HRs for a composite cardiovascular end point associated with a 10-mm Hg higher systolic HBP were 1.28 (1.01–1.62) and 1.22 (1.00–1.49), respectively. At high-normal CBP and in mild hypertension, the HRs were 1.24 (1.03–1.49) and 1.20 (1.06–1.37), respectively, for all cardiovascular events and 1.33 (1.07–1.65) and 1.30 (1.09–1.56), respectively, for stroke. In severe hypertension, the HRs were not significant (p≥0.20). Among people with optimal, normal, and high-normal CBP, 67 (5.0%), 187 (18.4%), and 315 (30.3%), respectively, had masked hypertension (HBP≥130 mm Hg systolic or ≥85 mm Hg diastolic). Compared to true optimal CBP, masked hypertension was associated with a 2.3-fold (1.5–3.5) higher cardiovascular risk. A limitation was few data from low- and middle-income countries.

Conclusions

HBP substantially refines risk stratification at CBP levels assumed to carry no or only mildly increased risk, in particular in the presence of masked hypertension. Randomized trials could help determine the best use of CBP vs. HBP in guiding BP management. Our study identified a novel indication for HBP, which, in view of its low cost and the increased availability of electronic communication, might be globally applicable, even in remote areas or in low-resource settings. Please see later in the article for the Editors'' Summary  相似文献   
945.
More and more antibody therapeutics are being approved every year, mainly due to their high efficacy and antigen selectivity. However, it is still difficult to identify the antigen, and thereby the function, of an antibody if no other information is available. There are obstacles inherent to the antibody science in every project in antibody drug discovery. Recent experimental technologies allow for the rapid generation of large-scale data on antibody sequences, affinity, potency, structures, and biological functions; this should accelerate drug discovery research. Therefore, a robust bioinformatic infrastructure for these large data sets has become necessary. In this article, we first identify and discuss the typical obstacles faced during the antibody drug discovery process. We then summarize the current status of three sub-fields of antibody informatics as follows: (i) recent progress in technologies for antibody rational design using computational approaches to affinity and stability improvement, as well as ab-initio and homology-based antibody modeling; (ii) resources for antibody sequences, structures, and immune epitopes and open drug discovery resources for development of antibody drugs; and (iii) antibody numbering and IMGT. Here, we review “antibody informatics,” which may integrate the above three fields so that bridging the gaps between industrial needs and academic solutions can be accelerated. This article is part of a Special Issue entitled: Recent advances in molecular engineering of antibody.  相似文献   
946.
Loquat canker disease, caused by Pseudomonas syringae pv. eriobotryae, is one of the most harmful diseases of commercial cultivars of loquat (Eriobotrya japonica). To introgress resistance to loquat canker, we identified the linkage group and position of the resistance locus derived from the related wild species bronze loquat (Eriobotrya deflexa). The segregation of resistance and susceptibility fit the expected ratio of 1:1 in 96 individuals from a three-way cross involving bronze loquat (heterozygous for resistance) and two cultivars of loquat (susceptible). The genomic region containing Pse-a was identified by using a genome scanning approach, and the loquat canker resistance locus was mapped at the top of linkage group 10 by applying novel simple sequence repeat (SSR) markers designed on the basis of the ‘Golden Delicious’ apple genome sequence. The constructed linkage group spans 69.4 cM and has an average marker density of 2.6 cM per marker. The developed molecular markers tightly linked to the loquat canker resistance locus will be useful for marker-assisted selection and for introgression of resistance into loquat in breeding programs.  相似文献   
947.
The optimization of antibodies is a desirable goal towards the development of better therapeutic strategies. The antibody 11K2 was previously developed as a therapeutic tool for inflammatory diseases, and displays very high affinity (4.6 pM) for its antigen the chemokine MCP-1 (monocyte chemo-attractant protein-1). We have employed a virtual library of mutations of 11K2 to identify antibody variants of potentially higher affinity, and to establish benchmarks in the engineering of a mature therapeutic antibody. The most promising candidates identified in the virtual screening were examined by surface plasmon resonance to validate the computational predictions, and to characterize their binding affinity and key thermodynamic properties in detail. Only mutations in the light-chain of the antibody are effective at enhancing its affinity for the antigen in vitro, suggesting that the interaction surface of the heavy-chain (dominated by the hot-spot residue Phe101) is not amenable to optimization. The single-mutation with the highest affinity is L-N31R (4.6-fold higher affinity than wild-type antibody). Importantly, all the single-mutations showing increase affinity incorporate a charged residue (Arg, Asp, or Glu). The characterization of the relevant thermodynamic parameters clarifies the energetic mechanism. Essentially, the formation of new electrostatic interactions early in the binding reaction coordinate (transition state or earlier) benefits the durability of the antibody-antigen complex. The combination of in silico calculations and thermodynamic analysis is an effective strategy to improve the affinity of a matured therapeutic antibody.  相似文献   
948.
It has been reported that acute exposure to diethylstilbestrol (DES) induces apoptosis in the testis, and antioxidants play a role in preventing DES-induced tissue damage. In this study, the effect of chronic exposure to DES on the antioxidants was examined in the testis and liver. Eight-week old male ICR mice were treated subcutaneously with various doses of DES for 20 days. Morphologically apparent apoptotic changes, 4-hydroxy-2-nonenal-positive cells and TUNEL-positive DNA-fragmentation, were demonstrated in the testis, but were minimal in the liver. Activities of antioxidants such as glutathione (GSH) peroxidase and GSH S -transferase decreased in both the liver and testis. The activity of Mn-superoxide dismutase (SOD) decreased in the liver but increased in the testis. The activity of Cu, Zn-SOD decreased in the liver but was unchanged in the testis. On Western and Northern blots, gamma-glutamylcysteine synthetase ( &#110 -GCS), a rate limiting enzyme of GSH synthesis, was increased in the liver dependent on the dose of DES. However, the expression of &#110 -GCS was reduced in the testis. Since quinones, metabolites of DES, generate reactive oxygen species, which damage DNA, antioxidants are important to prevent the damage. The data suggest that antioxidant activities are impaired by DES, and the levels of GSH are related to DES-induced apoptosis in the testis.  相似文献   
949.
The potential invasiveness of 28 freshwater fishes in northern Kyushu Island, Japan, was evaluated using the Fish Invasiveness Scoring Kit (FISK). The five co-authors scored the level of invasiveness for each species and calculated the total FISK scores; the maximum and minimum scores were then eliminated, and the mean of the remaining three scores was used as the final score for each species. The mean scores ranged from 11.0 (Hypomesus nipponensis) to 31.0 (Cyprinus carpio). The receiver operating characteristic curve indicated that the threshold value between fishes that present a high risk of invasion and the other species were 19.8.  相似文献   
950.
Histamine is a biological amine that plays an important role in allergic responses. However, the involvement of histamine signaling in late allergic responses in the skin is poorly understood. Therefore, we attempted to investigate the involvement of histamine signaling in late allergic responses, especially in keratinocytes (KCs). HaCaT KCs and normal human KCs (NHKs) predominantly expressed histamine H1 receptor (H1R) and H2 receptor (H2R). Histamine suppressed tumor necrosis factor α (TNF-α)- and interferon-γ (IFN-γ)-induced production of CC chemokine ligand 17(CCL17), a type 2 T-helper (Th2) chemokine, by HaCaT KCs. It suppressed the phosphorylation of p38 mitogen-activated protein (MAP) kinase, but not that of extracellular signal-regulated kinases (ERKs), and TNF-α- and IFN-γ-induced nuclear factor κB (NFκB) activity. In contrast, histamine enhanced the production of CXC chemokine ligand 10 (CXCL10), a Th1 chemokine, by TNF-α- and IFN-γ-stimulated HaCaT KCs and NHKs. TNF-α- and IFN-γ-induced CXCL10 production was upregulated by suppression of p38 MAP kinase or NF-κB activity, which could explain histamine involvement. We concluded that histamine suppresses CCL17 production by KCs by suppressing p38 MAP kinase and NF-κB activity through H1R and may act as a negative-feedback signal for existing Th2-dominant inflammation by suppressing CCL17 and enhancing CXCL10 production.  相似文献   
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