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71.
It is now well established that the growth of primary and metastatic tumors is associated with the formation of new blood vessels, and that the growth of these tumor cells is frequently dependent on this neovasculature. The observation that inhibition of tumor angiogenesis in mice can lead to tumor regression or dormancy generated high level of enthusiasm and interest in developing new treatment strategies for human cancer based on inhibiting tumor angiogenesis. This short review focuses on recent advances in angiogenesis-research in non-Hodgkin's lymphoma and Hodgkin's disease.  相似文献   
72.
Phytocystatins belong to the family of cysteine proteinases inhibitors. They are ubiquitously found in plants and carry out various significant physiological functions. These plant derived inhibitors are gaining wide consideration as potential candidate in engineering transgenic crops and in drug designing. Hence it is crucial to identify these inhibitors from various plant sources. In the present study a phytocystatin has been isolated and purified by a simple two‐step procedure using ammonium sulfate saturation and gel filtration chromatography on Sephacryl S‐100HR from Brassica alba seeds (yellow mustard seeds).The protein was purified to homogeneity with 60.3% yield and 180‐fold of purification. The molecular mass of the mustard seed cystatin was estimated to be nearly 26 000 Da by sodium dodecyl sulfate polyacrylamide gel electrophoresis as well as by gel filtration chromatography. The stokes radius and diffusion coefficient of the mustard cystatin were found to be 23A° and 9.4 × 10?7 cm2s?1 respectively. The isolated phytocystatin was found to be stable in the pH range of 6–8 and is thermostable up to 60 °C. Kinetic analysis revealed that the phytocystatin exhibited non‐competitive type of inhibition and inhibited papain more efficiently (Ki = 3 × 10?7 M) than ficin (Ki = 6.6 × 10?7 M) and bromelain (Ki = 7.7 × 10?7 M respectively). CD spectral analysis shows that it possesses 17.11% alpha helical content. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
73.

Background

We previously derived and validated a risk model to estimate mortality probability in children with septic shock (PERSEVERE; PEdiatRic SEpsis biomarkEr Risk modEl). PERSEVERE uses five biomarkers and age to estimate mortality probability. After the initial derivation and validation of PERSEVERE, we combined the derivation and validation cohorts (n = 355) and updated PERSEVERE. An important step in the development of updated risk models is to test their accuracy using an independent test cohort.

Objective

To test the prognostic accuracy of the updated version PERSEVERE in an independent test cohort.

Methods

Study subjects were recruited from multiple pediatric intensive care units in the United States. Biomarkers were measured in 182 pediatric subjects with septic shock using serum samples obtained during the first 24 hours of presentation. The accuracy of PERSEVERE 28-day mortality risk estimate was tested using diagnostic test statistics, and the net reclassification improvement (NRI) was used to test whether PERSEVERE adds information to a physiology-based scoring system.

Results

Mortality in the test cohort was 13.2%. Using a risk cut-off of 2.5%, the sensitivity of PERSEVERE for mortality was 83% (95% CI 62–95), specificity was 75% (68–82), positive predictive value was 34% (22–47), and negative predictive value was 97% (91–99). The area under the receiver operating characteristic curve was 0.81 (0.70–0.92). The false positive subjects had a greater degree of organ failure burden and longer intensive care unit length of stay, compared to the true negative subjects. When adding PERSEVERE to a physiology-based scoring system, the net reclassification improvement was 0.91 (0.47–1.35; p<0.001).

Conclusions

The updated version of PERSEVERE estimates mortality probability reliably in a heterogeneous test cohort of children with septic shock and provides information over and above a physiology-based scoring system.  相似文献   
74.
A marine bacterium, Micrococcus MCCB 104, isolated from hatchery water, demonstrated extracellular antagonistic properties against Vibrio alginolyticus, V. parahaemolyticus, V. vulnificus, V. fluviallis, V. nereis, V. proteolyticus, V. mediterranei, V cholerae and Aeromonas sp., bacteria associated with Macrobrachium rosenbergii larval rearing systems. The isolate inhibited the growth of V. alginolyticus during co-culture. The antagonistic component of the extracellular product was heat-stable and insensitive to proteases, lipase, catalase and alpha-amylase. Micrococcus MCCB 104 was demonstrated to be non-pathogenic to M. rosenbergii larvae.  相似文献   
75.
The locomotor activity rhythm of three supralittoral crustacean species, Tylos europaeus (terrestrial isopod) and Britorchestia brito and Talitrus saltator (amphipod, Talitridea), was investigated in Barkoukech Beach. The rhythm was monitored in individual animals in spring under continuous darkness and constant temperature. Results revealed that whatever the species, actograms and mean activity curves showed that specimens of T. europaeus and T. saltator concentrated their activity during the subjective night; whereas, B. brito concentrated its activity during the subjective day. The three species exhibited a circadian locomotor rhythm with mean circadian period, respectively, equal to 24h41′ ± 0h44′, 24h46′ ± 0h55′ and 25h21′ ± 1h16′. The most stable locomotor rhythm was found in T. saltator (0.444 ± 0.246). Furthermore, individuals of T. europaeus were significantly more active (10h47′ ± 2h52′) than the two amphipods. Differences in the activity patterns of the three species will be discussed as an adaptative strategy to respond to interspecific competitive interactions.  相似文献   
76.
77.
1. The impact of whole-lake lime (slaked lime, Ca(OH)2, and/or calcite, CaCO3) addition on plankton communities was evaluated in eutrophic hardwater lakes on the North American Boreal Plain.
2. Two lakes received a single treatment of lime (Ca(OH)2 at 74 or 107 mg L–1), two lakes received multiple treatments with Ca(OH)2 and/or CaCO3 (5–78 mg L–1), and four lakes were untreated and served as reference systems.
3. Over the long-term (> 1 year), phytoplankton biomass was reduced in multiple-dose lakes, but not in single-dose lakes. Cyanobacteria typically dominated the algal community in the years before, during and after lime treatment in both single- and multiple-dose lakes.
4. In the single-dose lakes, randomized intervention analysis showed no significant change in the biomass of zooplankton after lime addition.  相似文献   
78.

Background  

Ventricular tachycardia (VT) and ventricular fibrillation (VF) are the most serious cardiac arrhythmias that require quick and accurate detection to save lives. Automated external defibrillators (AEDs) have been developed to recognize these severe cardiac arrhythmias using complex algorithms inside it and determine if an electric shock should in fact be delivered to reset the cardiac rhythm and restore spontaneous circulation. Improving AED safety and efficacy by devising new algorithms which can more accurately distinguish shockable from non-shockable rhythms is a requirement of the present-day because of their uses in public places.  相似文献   
79.
The potentially tritopic bridging ligand 4-(pyrid-4-yl)-1,2,4-triazole (pytz) reacts with cadmium(II) nitrate tetrahydrate, Cd(NO3)2·4H2O and sodium dicyanamide (Na-dca) to form the molecular complex [Cd(dca)2Npy-pytz)2(H2O)2] (1). The cadmium atom lies on a center of inversion and is coordinated in a slightly distorted octahedral geometry by the trans-oriented pytz ligands, dicyanamide anions and aqua ligands. The pytz ligand coordinates through the Npyridin atom to the metal atom. The molecular complexes are connected to a 3D supramolecular network by O-H···Ndca and O-H···Ntriazole hydrogen bonds. From zinc(II) bromide and pytz the compound 1D-[ZnBr2(μ-κNpy,Ntz-pytz)] (2) is obtained where the pytz-ligand bridges between the tetracoordinated zinc(II) atoms through coordination of its Npyridine- and Ntriazole-atoms. Adjacent chains are connected through C-H···Br and C-H···N hydrogen bonds to form a 3D supramolecular structure. Single crystals of 2 crystallize homochiral in the non-centrosymmetric space group P212121. The origin of the homochirality is the formation of hydrogen-bonded helices around the 21 screw axes with the same sense of rotation (left-handed or M in the investigated crystal). Cd(NO3)2·4H2O, pytz and sodium thiocyanate (NaSCN) give the framework 3D-[Cd(μ-SCN)2(μ-κNpy,Ntz-pytz)] (3). Parallel layers of 2D-{Cd(μ-SCN)2}-nets with distorted (6,3)-net topology are assembled by the bridging pytz-ligands into a 3D-structure. The pytz-ligand bridges between two cadmium atoms by Npyridine- and Ntriazole-coordination.  相似文献   
80.
Goodpasture antigen-binding protein-1 (GPBP-1) is an exportable non-conventional Ser/Thr kinase that regulates glomerular basement membrane collagen organization. Here we provide evidence that GPBP-1 accumulates in the cytoplasm of differentiating mouse myoblasts prior to myosin synthesis. Myoblasts deficient in GPBP-1 display defective myofibril formation, whereas myofibrils assemble with enhanced efficiency in those overexpressing GPBP-1. We also show that GPBP-1 targets the previously unidentified GIP130 (GPBP-interacting protein of 130 kDa), which binds to myosin and promotes its myofibrillar assembly. This report reveals that GPBP-1 directs myofibril formation, an observation that expands its reported role in supramolecular organization of structural proteins to the intracellular compartment.  相似文献   
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