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71.
Heparan sulfate is a highly sulfated carbohydrate polymer that binds to and modulates the activities of numerous proteins. The formation of these protein-binding domains in heparan sulfate is dependent on a series of biosynthetic reactions that modify the polysaccharide backbone; the initiating and rate-limiting steps of this process are the N-deacetylation and N-sulfation of N-acetylglucosamine residues in the polymer. We now report that in the rat liver, biosynthesis of heparan sulfate utilizes a single protein that possesses both N-deacetylase and N-sulfotransferase activities. This was accomplished by demonstrating that both activities resided in a purified soluble fusion protein containing the Golgi-lumenal portion of the enzyme. We propose that this protein be renamed the rat liver Golgi heparan sulfate N-deacetylase/N-sulfotransferase.  相似文献   
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73.
Diallyl trisulfide (DATS), a chemopreventive dietary constituent and extracted from garlic, has been shown to against cultured many types of human cancer cell liens but the fate of apoptosis in murine leukemia cells in vitro and immune responses in leukemic mice remain elusive. Herein, we clarified the actions of DATS on growth inhibition of murine leukemia WEHI‐3 cells in vitro and used WEHI‐3 cells to generate leukemic mice in vivo, following to investigate the effects of DATS in animal model. In in vitro study, DATS induced apoptosis of WEHI‐3 cells through the G0/G1 phase arrest and induction of caspase‐3 activation. In in vivo study DATS decreased the weight of spleen of leukemia mice but did not affect the spleen weight of normal mice. DATS promoted the immune responses such as promotions of the macrophage phagocytosis and NK cell activities in WEHI‐3 leukemic and normal mice. However, DATS only promotes NK cell activities in normal mice. DATS increases the surface markers of CD11b and Mac‐3 in leukemia mice but only promoted CD3 in normal mice. In conclusion, the present study indicates that DATS induces cell death through induction of apoptosis in mice leukemia WHEI‐3 cells. DATS also promotes immune responses in leukemia and normal mice in vivo. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 1343–1353, 2015.  相似文献   
74.
Although there are few reports regarding α‐phellandrene (α‐PA), a natural compound from Schinus molle L. essential oil, there is no report to show that α‐PA induced DNA damage and affected DNA repair associated protein expression. Herein, we investigated the effects of α‐PA on DNA damage and repair associated protein expression in murine leukemia cells. Flow cytometric assay was used to measure the effects of α‐PA on total cell viability and the results indicated that α‐PA induced cell death. Comet assay and 4,6‐diamidino‐2‐phenylindole dihydrochloride staining were used for measuring DNA damage and condensation, respectively, and the results indicated that α‐PA induced DNA damage and condensation in a concentration‐dependent manner. DNA gel electrophoresis was used to examine the DNA damage and the results showed that α‐PA induced DNA damage in WEHI‐3 cells. Western blotting assay was used to measure the changes of DNA damage and repair associated protein expression and the results indicated that α‐PA increased p‐p53, p‐H2A.X, 14‐3‐3‐σ, and MDC1 protein expression but inhibited the protein of p53, MGMT, DNA‐PK, and BRCA‐1. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 1322–1330, 2015.  相似文献   
75.
Some nasopharyngeal carcinoma (NPC) patients may present convincing radiological evidence mimicking residual or recurrent tumor after radiotherapy. However, by means of biopsies and long term follow-up, the radiologically diagnosed residuals/recurrences are not always what they appear to be. We report our experience on this “phantom tumor” phenomenon. This may help to avoid the unnecessary and devastating re-irradiation subsequent to the incorrect diagnosis.In this longitudinal cohort study, we collected 19 patients of image-based diagnosis of residual/recurrent NPC during the period from Feb, 2010 to Nov. 2016, and then observed them until June, 2019. They were subsequently confirmed to have no residual/recurrent lesions by histological or clinical measures. Image findings and pathological features were analyzed.Six patients showed residual tumors after completion of radiotherapy and 13 were radiologically diagnosed to have recurrences based on magnetic resonance imaging (MRI) criteria 6 to 206 months after radiotherapy. There were 3 types of image patterns: extensive recurrent skull base lesions (10/19); a persistent or residual primary lesion (3/19); lesions both in the nasopharynx and skull base (6/19). Fourteen patients had biopsy of the lesions. The histological diagnoses included necrosis/ inflammation in 10 (52.7%), granulation tissue with inflammation in 2, and reactive epithelial cell in 1. Five patients had no pathological proof and were judged to have no real recurrence/residual tumor based on the absence of detectable plasma EB virus DNA and subjective judgment. These 5 patients have remained well after an interval of 38–121 months without anti-cancer treatments.Image-based diagnosis of residual or recurrent nasopharyngeal carcinoma may be unreliable. False positivity, the “phantom tumor phenomenon”, is not uncommon in post-radiotherapy MRI. This is particularly true if the images show extensive skull base involvement at 5 years or more after completion of radiotherapy. MRI findings compatible with NPC features must be treated as a real threat until proved otherwise. However, the balance between under- and over-diagnosis must be carefully sought. Without a pathological confirmation, the diagnosis of residual or recurrent NPC must be made taking into account physical examination results, endoscopic findings and Epstein-Barr virus viral load. A subjective medical judgment is needed based on clinical and laboratory data and the unique anatomic complexities of the nasopharynx.  相似文献   
76.
Journal of Thrombosis and Thrombolysis - Newer generation durable polymer drug-eluting stents (DP-DES) and biodegradable polymer DES (BP-DES) have similar efficacy with dual-antiplatelet therapy...  相似文献   
77.
Introduction: Successful treatment outcomes for viral respiratory tract infections presenting from primary health care to quaternary hospitals will only be achieved with rapid, sensitive and specific identification of pathogens to allow effective pathogen-specific antiviral therapy and infection control measures.

Areas covered: This review aims to explore the different point-of-care tests currently available to diagnose viral respiratory tract infections, discuss the advantages and limitations of point-of-care testing, and provide insights into the future of point-of-care tests. The following databases were searched: Medline (January 1996 to 30 September 2017) and Embase (1988 to 30 September 2017), using the following keywords: ‘point of care’, ‘respiratory virus’, ‘influenza’, ‘RSV’, ‘diagnostics’, ‘nucleic acid test’ and ‘PCR’.

Expert commentary: Viral respiratory tract infections cause significant morbidity and mortality worldwide, and point-of-care tests are facilitating the rapid identification of the pathogen responsible given the similarities in clinical presentation.  相似文献   

78.
Background: Preoperative malnutrition is increasingly prevalent in patients undergoing cardiac surgery. Although prealbumin is a widely used indicator of nutrition status, its use in the preoperative assessment of patients undergoing cardiac surgery is not well defined. The purpose of this study is to determine the impact of preoperative prealbumin levels on outcomes after cardiac surgery. Materials and Methods: Data were prospectively gathered from February 2013 to July 2013 on 69 patients undergoing cardiac surgery. Prealbumin levels were obtained within 24 hours of surgery. Patients were divided into 2 groups based on a prealbumin cutoff value of 20 mg/dL. Results: Of the 69 patients, 32 (46.4%) had a preoperative prealbumin ≤20 mg/dL. There was no correlation between prealbumin levels and body mass index (r = ?0.13, P = .28). Likewise, there was no correlation between preoperative albumin and prealbumin levels (r = 0.09, P = .44). Nine of 32 (28.1%) patients with low preoperative prealbumin levels had postoperative infections compared with 2 of 37 (5.4%) patients with high prealbumin levels (P = .010). Patients with low prealbumin levels also had increased risk of postoperative intubation for >12 hours (P = .010). Conclusions: Patients undergoing cardiac surgery with preoperative prealbumin levels of ≤20 mg/dL have an increased risk for postoperative infections and the need for longer mechanical ventilation. If feasible, nutrition optimization of such patients may be considered prior to cardiac surgery.  相似文献   
79.

Background

Atrial fibrillation (AF) is the most common sustained arrhythmia, and pulmonary veins (PVs) play a critical role in triggering AF. Angiotensin (Ang)‐(1‐7) regulates calcium (Ca2+) homoeostasis and also plays a critical role in cardiovascular pathophysiology. However, the role of Ang‐(1‐7) in PV arrhythmogenesis remains unclear.

Materials and methods

Conventional microelectrodes, whole‐cell patch‐clamp and the fluo‐3 fluorimetric ratio technique were used to record ionic currents and intracellular Ca2+ in isolated rabbit PV preparations and in single isolated PV cardiomyocytes, before and after administration of Ang‐(1‐7).

Results

Ang (1‐7) concentration dependently (0.1, 1, 10 and 100 nmol/L) decreased PV spontaneous electrical activity. Ang‐(1‐7) (100 nmol/L) decreased the late sodium (Na+), L‐type Ca2+ and Na+‐Ca2+ exchanger currents, but did not affect the voltage‐dependent Na+ current in PV cardiomyocytes. In addition, Ang‐(1‐7) decreased intracellular Ca2+ transient and sarcoplasmic reticulum Ca2+ content in PV cardiomyocytes. A779 (a Mas receptor blocker, 3 μmol/L), L‐NAME (a NO synthesis inhibitor, 100 μmol/L) or wortmannin (a specific PI3K inhibitor, 10 nmol/L) attenuated the effects of Ang‐(1‐7) (100 nmol/L) on PV spontaneous electric activity.

Conclusion

Ang‐(1‐7) regulates PV electrophysiological characteristics and Ca2+ homoeostasis via Mas/PI3K/eNOS signalling pathway.  相似文献   
80.
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