Publications by authors named "John C Yang"

Candida albicans can cause candidemia in neutropenic and critically ill patients and oropharyngeal candidiasis in human immunodeficiency virus (HIV)-positive patients with low CD4(+) counts. Because all patients at risk do not develop Candida infections, it is possible that a patient's genetic background might play a role in his or her susceptibility to infection. Autophagy mediates pathogen clearance and modulation of inflammation.

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Systemic Candida albicans infection causes high morbidity and mortality and is associated with neutropenia; however, the roles of other innate immune cells in pathogenesis are poorly defined. Here, using a mouse model of systemic candidiasis, we found that resident macrophages accumulated in the kidney, the main target organ of infection, and formed direct contacts with the fungus in vivo mainly within the first few hours after infection. Macrophage accumulation and contact with Candida were both markedly reduced in mice lacking chemokine receptor CX3CR1, which was found almost exclusively on resident macrophages in uninfected kidneys.

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Background: Candidemia is a severe invasive fungal infection with high mortality. Recognition of Candida species is mediated through pattern recognition receptors such as Toll-like receptors (TLRs). This study assessed whether genetic variation in TLR signaling influences susceptibility to candidemia.

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Background:  Candida bloodstream infections cause significant morbidity and mortality among hospitalized patients. Although clinical and microbiological factors affecting prognosis have been identified, the impact of genetic variation in the innate immune responses mediated by cytokines on outcomes of infection remains to be studied.

Methods:  A cohort of 338 candidemia patients and 351 noninfected controls were genotyped for single-nucleotide polymorphisms (SNPs) in 6 cytokine genes (IFNG, IL10, IL12B, IL18, IL1β, IL8) and 1 cytokine receptor gene (IL12RB1).

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Background: Candidemia is an important cause of morbidity and mortality in critically ill patients or patients undergoing invasive treatments. Dectin-1 is the main β-glucan receptor, and patients with a complete deficiency of either dectin-1 or its adaptor molecule CARD9 display persistent mucosal infections with Candida albicans. The role of genetic variation of DECTIN-1 and CARD9 genes on the susceptibility to candidemia is unknown.

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A chromophore-donor-acceptor assembly [Ru(bpyCOOH)(bpyCH(2)MV(2+)) (bpyCH(2)PTZ)](4+)(1) (where bpyCOOH = 4-carboxylic acid-4'-methyl-2,2'-bipyridine, bpyCH(2)MV(2+) = 1-[(4'-methyl-2,2'-bipyridin-4-yl)methyl]-1'-methyl-4,4'-bipyridinediium, and bpyCH(2)PTZ = 10-[(4'-methyl-2,2'-bipyridin-4-yl)methyl]phenothiazine) has been adsorbed on the surface of nanocrystalline ZrO(2) and its excited state properties studied by emission and transient absorption spectroscopy. In deaerated acetonitrile solution, the complex emits weakly with an emission quantum yield of phi(em) approximately equal to 0.01 with an excited-state lifetime of tau approximately equal to 20 ps.

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Molecular electronics has been proposed as a pathway for high-density nanoelectronic devices. This pathway involves the development of a molecular memory device based on reversible switching of a molecule between two conducting states in response to a trigger, such as an applied voltage. Here we demonstrate that voltage-triggered switching is indeed a molecular phenomenon by carrying out studies on the same molecule using three different experimental configurations-scanning tunnelling microscopy, crossed-wire junction, and magnetic-bead junction.

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Overlayer thin films of vinylbipyridine (vbpy)-containing Ru and Zn complexes have been formed on top of ruthenium dye complexes adsorbed to TiO(2) by reductive electropolymerization. The goal was to create an efficient, water-stable photoelectrode or electrodes. An adsorbed-[Ru(vbpy)(2)(dcb)](PF(6))(2)/poly-[Ru(vbpy)(3)](PF(6))(2) surface composite displays excellent stability toward dissolution in water, but the added overlayer film greatly decreases incident photon-to-current conversion efficiencies (IPCE) in propylene carbonate with I(3)(-)/I(-) as the carrier couple.

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Current-voltage (I-V) characteristics for metal-molecule-metal junctions formed from three classes of molecules measured with a simple crossed-wire molecular electronics test-bed are reported. Junction conductance as a function of molecular structure is consistent with I-V characteristics calculated from extended Hückel theory coupled with a Green's function approach, and can be understood on the basis of bond-length alternation.

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Surface electrochemical and photoelectrochemical measurements on ITO (In(2)O(3):Sn) or TiO(2) of two proline assemblies are reported. Surface coverage on ITO of Pbp-pra(Ru(II)b(2)m)-OH(PF(6))(2) and Bpb-pra(Ru(II)b(2)m)-OCH(3)(CF(3)CO(2))(2) are (1.5-2.

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