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1.
Six volunteers experienced severe inflammatory response during the Phase I clinical trial of a monoclonal antibody that was designed to stimulate a regulatory T cell response. Soon after the trial began, each volunteer experienced a “cytokine storm”, a dramatic increase in cytokine concentrations. The monoclonal antibody, TGN1412, raised serum concentrations of both pro- and anti-inflammatory cytokines το very hiγh values during the first day, while lymphocyte and monocyte concentrations plummeted. Because the subjects were healthy and had no prior indications of immune deficiency, this event provided an unusual opportunity to study the dynamic interactions of cytokines and other measured parameters. Here, the response histories of nine cytokines have been modeled by a set of linear ordinary differential equations. A general search procedure identifies parameters of the model, whose response fits the data well during the five-day measurement period. The eighteenth-order model reveals plausible cause-and-effect relationships among the cytokines, showing how each cytokine induces or inhibits other cytokines. It suggests that perturbations in IL2, IL8, and IL10 have the most significant inductive effect, while IFN-γ and IL12 have the greatest inhibiting effect on other cytokine concentrations. Although TNF-α is a major pro-inflammatory factor, IFN-γ and three other cytokines have faster initial and median response to TGN1412 infusion. Principal-component analysis of the data reveals three clusters of similar cytokine responses: [TNF-α, IL1, IL10], [IFN-γ, IL2, IL4, IL8, and IL12], and [IL6]. IL1, IL6, IL10, and TNF-α have the highest degree of variability in response to uncertain initial conditions, exogenous effects, and parameter estimates. This study illuminates details of a cytokine storm event, and it demonstrates the value of linear modeling for interpreting complex, coupled biological system dynamics from empirical data.  相似文献   
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Pseudomonas mendocina DLHK is an aerobic bacterium isolated from a biotrickling reactor which can remove nitric oxide, a common air pollutant from combustion exhaust gas. Here, we present the draft genome of Pseudomonas mendocina DLHK.  相似文献   
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Soil-transmitted helminths are parasitic nematodes that inhabit the human intestine. These parasites, which include two hookworm species, Ancylostoma duodenale and Necator americanus, the whipworm Trichuris trichiura , and the large roundworm Ascaris lumbricoides , infect upwards of two billion people and are a major cause of disease burden in children and pregnant women. The challenge with treating these diseases is that poverty, safety, and inefficient public health policy have marginalized drug development and distribution to control infection in humans. Anthelmintics (anti-worm drugs) have historically been developed and tested for treatment of non-human parasitic nematodes that infect livestock and companion animals. Here we systematically compare the in vitro efficacy of all major anthelmintic classes currently used in human therapy (benzimidazoles, nicotinic acetylcholine receptor agonists, macrocyclic lactones, nitazoxanide) against species closely related to human parasitic nematodes-Ancylostoma ceylanicum, Trichuris muris , and Ascaris suum --- as well as a rodent parasitic nematode used in veterinary drug discovery, Heligmosomoides bakeri , and the free-living nematode Caenorhabditis elegans. Extensive in vitro data is complemented with single-dose in vivo data in three rodent models of parasitic diseases. We find that the effects of the drugs in vitro and in vivo can vary greatly among these nematode species, e.g., the efficacy of albendazole is strong on A. ceylanicum but weak on H . bakeri . Nonetheless, certain commonalities of the in vitro effects of the drugs can be seen, e.g., nitazoxanide consistently shows an all-or-nothing response. Our in vitro data suggest that further optimization of the clinical efficacy of some of these anthelmintics could be achieved by altering the treatment routine and/or dosing. Most importantly, our in vitro and in vivo data indicate that the hookworm A. ceylanicum is a particularly sensitive and useful model for anthelmintic studies and should be incorporated early on in drug screens for broad-spectrum human soil-transmitted helminth therapies.  相似文献   
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Purpose

The coronary calcium score (CCS) predicts significant coronary artery disease (CAD) in the general population. While moderate chronic kidney disease (CKD) is associated with high CCS, the use of CCS to predict significant CAD in these patients is unknown.

Methods

A total of 704 patients underwent computed tomography coronary angiography for the assessment of CCS and CAD. Sixty-nine (10 %) patients had moderate CKD, defined by an estimated glomerular filtration rate (eGFR) between 30 and 59 mL/min/1.73m2, and the remaining patients were considered to be without significant CKD (eGFR?≥?60 mL/min/1.73m2).

Results

Patients with moderate CKD were older, had a higher CCS, and a higher prevalence of obstructive CAD than patients without significant CKD. Receiver-operator curve analysis showed that CCS predicted the presence of obstructive CAD in both patients with moderate CKD and those without significant CKD. In patients with moderate CKD, the optimal cut-off value of CCS to diagnose obstructive CAD was 140 (sensitivity 73 % and specificity of 70 %), and is 2.8 fold higher than in patients without significant CKD (cut-off value?=?50; sensitivity 75 % and specificity 75 %).

Conclusion

The present results demonstrate that CCS can predict obstructive CAD in patients with moderate CKD, although the optimal cut-off value is higher than in patients without significant CKD.  相似文献   
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Evolving evidence supports that cyclooxygenase-1 (COX-1) takes part in colon carcinogenesis. The effects of COX-1 inhibition on colon cancer cells, however, remains obscured. In this study, we demonstrate that COX-1 inhibitor sc-560 inhibited colon cancer cell proliferation with concomitant G0/G1-phase cell cycle arrest. The anti-proliferative effect was associated with down-regulation of c-Fos, cyclin E2 and E2F-1 and up-regulation of p21Waf1/Cip1 and p27Kip1. In addition, sc-560 induced macroautophagy, an emerging mechanism of tumor suppression, as evidenced by the formation of LC3+ autophagic vacuoles, enhanced LC3 processing, and the accumulation of acidic vesicular organelles and autolysosomes. In this connection, 3-methyladenine, a Class III phosphoinositide 3-kinase inhibitor, significantly abolished the formation of LC3+ autophagic vacuoles and the processing of LC3 induced by sc-560. To conclude, this study reveals the unreported relationship between COX-1 and proliferation/macroautophagy of colon cancer cells.  相似文献   
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