Urban landscape genomics identifies fine-scale gene flow patterns in an avian invasive.

Invasive species exert a serious impact on native fauna and flora and have been the target of many eradication and management efforts worldwide. However, a lack of data on population structure and history, exacerbated by the recency of many species introductions, limits the efficiency with which such species can be kept at bay. In this study we generated a novel genome of high assembly quality and genotyped 4735 genome-wide single nucleotide polymorphic (SNP) markers from 78 individuals of an invasive population of the Javan Myna Acridotheres javanicus across the island of Singapore. We inferred limited population subdivision at a micro-geographic level, a genetic patch size (~13-14 km) indicative of a pronounced dispersal ability, and barely an increase in effective population size since introduction despite an increase of four to five orders of magnitude in actual population size, suggesting that low population-genetic diversity following a bottleneck has not impeded establishment success. Landscape genomic analyses identified urban features, such as low-rise neighborhoods, that constitute pronounced barriers to gene flow. Based on our data, we consider an approach targeting the complete eradication of Javan Mynas across Singapore to be unfeasible. Instead, a mixed approach of localized mitigation measures taking into account urban geographic features and planning policy may be the most promising avenue to reducing the adverse impacts of this urban pest. Our study demonstrates how genomic methods can directly inform the management and control of invasive species, even in geographically limited datasets with high gene flow rates.

Clinical value of electrophysiology in determining the diagnosis of visual dysfunction in neuro-ophthalmology patients.

PURPOSE: To assess clinical value of visual electrophysiology in identifying causes of visual dysfunction in patients referred from neuro-ophthalmology clinics. METHODS: A review of 410 subjects (aged 0.3-88 years) referred for visual electrophysiology from neuro-ophthalmologists between 2009 and 2013 was performed. Subjects were divided into those with unexplained poor vision, visual field defects, visual symptoms or other reasons (e.g. monitoring for drug toxicity or known conditions). Subjects underwent pattern, full-field and multifocal electroretinography (ERG) and pattern visual evoked potential (VEP) tests. Flash and multifocal VEP were included where indicated. RESULTS: Most subjects referred for poor vision (n = 158) had electrophysiology findings suggestive of retinopathy (37 %) or post-retinal pathology (34 %). Those with poorer vision (worse than 6/24) were more likely to have abnormal recordings (86 vs. 62 %, p = 0.002). Among subjects with unexplained visual field defects (n = 102), findings of retinopathy, post-retinal pathology and normal recordings were noted in 31, 24 and 28 %, respectively. Most subjects with other visual symptoms (n = 97) had normal findings (69 %). The multifocal ERG was most sensitive for detecting retinopathy (96 %) and maculopathy (95 %), while pattern VEP was most sensitive for post-retinal pathology (94 %). An indeterminate result was noted in 9 %. CONCLUSION: Electrophysiology was effective in differentiating between retinopathy, post-retinal pathology and normality in 91 % of subjects. Pre-testing provisional diagnoses of retinopathy and post-retinal pathology were revised in 30 and 42 %, respectively, after electrophysiology. Appreciation of characteristics of each test, correlation with the clinical picture and interpretation of results in totality are required to localize the site of pathology.

Clinical and immunochemical profiles of food challenge proven or anaphylactic shrimp allergy in tropical Singapore.

BACKGROUND: Shellfish allergy in Singapore is highly prevalent, and shrimp allergy is the most common. OBJECTIVE: This study aims to evaluate the clinical characteristics and immunological phenotype of shellfish allergy in this population. METHODS: Patients with self-reported shellfish allergy were recruited from outpatient clinics of three large hospitals and from a population survey. Open oral food challenges (OFC) to glass prawn (Litopenaeus vannamei) and tiger prawn (Penaeus monodon) were carried out on all patients except for those who had a history of severe anaphylaxis. Skin prick tests (SPT) and specific IgE to crude and recombinant allergens were carried out to evaluate shrimp and dust mite sensitization. Immunoblots were used to assess IgE-binding proteins. RESULTS: The 104 patients recruited were categorized into shellfish allergic (SA) when OFC was positive or had a history of severe anaphylaxis (n = 39), shellfish tolerant (ST) when OFC was negative (n = 27), and house dust mite positive controls (HDM(+) ) who were ST (n = 38). Oral symptoms (87.1%) were the predominant clinical manifestation. Positive challenge doses ranged from 2 to 80 g of cooked shrimp, with 25/52 patients reacting to either one or both shrimps challenged. The presence of specific IgE to shrimp either by SPT and/or ImmunoCAP(®) assay provided diagnostic test sensitivity of 82% and specificity of 22.2%. The inclusion of specific IgE to shrimp tropomyosin and IgE immunoblots with shrimp extracts did not improve the diagnostic proficiency substantially. CONCLUSIONS AND CLINICAL RELEVANCE: This study highlights the predominance of oral symptoms in shrimp allergy in tropical Asia and that a high provocation dose may be necessary to reveal shrimp allergy. Furthermore, specific IgE diagnostic tests and immunoblots were of limited use in this population.

Mutation of Tec family kinases alters T helper cell differentiation.

The Tec kinases Rlk and Itk are critical for full T cell receptor (TCR)-induced activation of phospholipase C-gamma and mitogen-activated protein kinase. We show here that the mutation of Rlk and Itk impaired activation of the transcription factors NFAT and AP-1 and production of both T helper type 1 (TH1) and TH2 cytokines. Consistent with these biochemical defects, Itk-/- mice did not generate effective TH2 responses when challenged with Schistosoma mansoni eggs. Paradoxically, the more severely impaired Rlk-/-Itk-/- mice were able to mount a TH2 response and produced TH2 cytokines in response to this challenge. In addition, Rlk-/-Itk-/- cells showed impaired TCR-induced repression of the TH2-inducing transcription factor GATA-3, suggesting a potential mechanism for TH2 development in these hyporesponsive cells. Thus, mutations that affect Tec kinases lead to complex alterations in CD4+ TH cell differentiation.

Synthesis and properties of a germanium(II) metalloheterocycle derived from 1,8-di(isopropylamino)naphthalene. A novel ligand leading to formation of Ni[Ge[((i)PrN)(2)C(10)H(6)]]4).

A novel mononuclear germylene, Ge[1,8-((i)PrN)(2)C(10)H(6)] (1), was isolated as a stable crystalline solid by the reaction of Li(2)[1,8-((i)PrN)(2)C(10)H(6)] with GeCl(2)(1,4-dioxane). Structural examination of 1 shows that this compound possesses a planar six-membered heterocyclic ring system with a Ge(II) center and that the steric impact of the substituents on the nitrogen centers is greater than that for the related five-membered metalloheterocycles. Compound 1 is readily oxidized with elemental S and Se and the structural details for the dinuclear product [[1,8-((i)PrN)(2)C(10)H(6)]Ge(micro-S)](2) are reported. Furthermore, the lone pair of electrons on the Ge(II) center in 1 allows this species to function as a novel ligand for the preparation of the unique tetrakis(germylene) complex Ni[Ge[((i)PrN)(2)C(10)H(6)]](4) (4). The structural features of 4 are reported and show that the germylene ligand, when coordinated to the Ni(0) center, now exhibited a twisted (nonplanar) heterometallocycle and a cone angle of 145 degrees.

Synthesis of diynes and tetraynes from in situ desilylation/dimerization of acetylenes.

[reaction: see text]. An efficient method for the in situ desilylation/oxidative dimerization of (trialkylsilyl)acetylenes is described. This protocol avoids the complications encountered with sensitive diynes by eliminating the deprotection and isolation steps. Various aromatic and alkyl diynes and tetraynes can be synthesized in a straightforward manner in good yields (82-99%) from TIPS-protected acetylenes. This method facilitates the efficient synthesis of novel tetrayne-bridged acetylenic cyclophanes 6 and 7 in a direct manner.

Tungsten oxo salicylate complexes from tungsten hexachloride reactions systems.

Tungsten hexachloride is a potent halogen-transfer agent, capable of reacting directly with salicylic acid to generate a tungsten oxo fragment and salicoyl chloride. As a result, oxo complexes dominate the chemistry of tungsten(VI) salicylates. Both mono- and disalicylate substituted tungsten oxo complexes are accessible. The Brønsted free acid W(=O)Cl(Hsal)(sal) complex is a sparingly soluble, presumably polymeric material that can be dissolved in THF. The THF adduct has been characterized by NMR spectroscopy, although an X-ray crystallographic study indicates that the product cocrystallizes with a structurally analogous d(1) WCl(2)(Hsal.THF)(sal) byproduct. The remaining chloride ligand in W(=O)Cl(Hsal)(sal) is replaced by a bridging oxo unit when the reaction contains a significant excess of salicylic acid. The product "linear" oxo bridged ditungsten complex, [W(=O)(Hsal)(sal)](2)O, forms intramolecular hydrogen bonds, accounting for its high solubility in noncoordinating solvents. An X-ray study shows that the intramolecular Hsal.sal hydrogen bonding in this complex accommodates a more linear W-O-W arrangement than does a previously observed class of isostructural diolate derivatives. Tungsten oxo tetrachloride, formed in the initial reaction between salicylic acid and WCl(6), also reacts with the salicoyl chloride byproduct to generate tungsten salicoylate (OAr-2-COCl) complexes.

Th1/Th2 effector choice in parasitic infection: decision making by committee.

Parasitic infections frequently result in highly polarized CD4+ T cell responses characterized by dominant Th1 or Th2 cytokine production profiles. Although previously thought to be strictly dependent on signaling by the differentiative cytokines, IL-12 and IL-4, recent data indicate that this polarization may be primarily decided instead by a series of different factors intrinsic to the pathogen-antigen-presenting-cell interaction that influence T cell priming.

Synthesis and X-ray crystal structure determination of first examples of donor-functionalized terphenyl lanthanide complexes.

The molecular structures of novel donor-functionalized terphenyl derivatives of trivalent ytterbium, yttrium, and samarium of composition [DanipYb(mu2-Cl)2(mu3-Cl)Li(THF)]2 (1) and [DanipLn(mu2-Cl)2(mu2-Cl)Li(THF)2]2 (Ln = Y, 2; Ln = Sm, 3) are reported [Danip = 2,6-di(o-anisol)phenyl]. The complexes are obtained from the reaction of equimolar amounts of DanipLi and LnCl3 (Ln = Yb, Y, Sm) in tetrahydrofuran at room temperature in 60% yield. 1-2 toluene crystallizes in the monoclinic space group Ponebar. Crystal data for 1-2 toluene at 203 K: a = 9.7281(9) A; b = 12.7989(12) A; c = 13.4870(12) A; alpha = 91.553(2) degrees; beta = 103.957(2) degrees; gamma = 109.916(2) degrees; V = 1521.2(2) A(3); Z' = 1; D(calcd) = 1.615 g cm(-3); R1 = 3.43%. 2-toluene crystallizes in the monoclinic space group Ponebar. Crystal data for 2-toluene at 203 K: a = 10.4152(10) A; b = 12.5783(12) A; c = 14.4640(14) A; alpha = 69.963(2) degrees; beta = 80.900(2) degrees; gamma = 66.603(2) degrees; V = 1633.3(3) A(3); Z' = 1; D(calcd) = 1.386 g cm(-3); R1 = 4.07%. 3-toluene crystallizes in the monoclinic space group Ponebar. Crystal data for 3-toluene at 203 K: a = 10.3457(8) A; b = 12.5658(10) A; c = 14.4365(11) A; alpha = 70.2250(10) degrees; beta = 81.2820(10) degrees; gamma = 66.8330(10) degrees; V = 1623.3(2) A(3); Z' = 1; D(calcd) = 1.521 g cm(-3); R1 = 3.40%. Complexes 1-3 represent first examples of donor-functionalized terphenyl complexes of the elements ytterbium, yttrium, and samarium, respectively. The molecular structures of 1-3 feature a "constraint geometry" type arrangement of the Danip ligand at the lanthanide atom. The complexes reported are dimeric and composed of lithium chloride bridged DanipLnCl(2) moieties (Ln = Yb, Y, Sm), stabilized through additional coordination of two methoxy functions to the lanthanide atom.

Inactivation of LRG-47 and IRG-47 reveals a family of interferon gamma-inducible genes with essential, pathogen-specific roles in resistance to infection.

The cytokine interferon (IFN)-gamma regulates immune clearance of parasitic, bacterial, and viral infections; however, the underlying mechanisms are poorly understood. Recently, a family of IFN-gamma-induced genes has been identified that encode 48-kD GTP-binding proteins that localize to the endoplasmic reticulum of cells. The prototype of this family, IGTP, has been shown to be required for host defense against acute infections with the protozoan parasite Toxoplasma gondii, but not for normal clearance of the bacterium Listeria monocytogenes and murine cytomegalovirus (MCMV). To determine whether other members of the gene family also play important roles in immune defense, we generated mice that lacked expression of the genes LRG-47 and IRG-47, and examined their responses to representative pathogens. After infection with T. gondii, LRG-47-deficient mice succumbed uniformly and rapidly during the acute phase of the infection; in contrast, IRG-47-deficient mice displayed only partially decreased resistance that was not manifested until the chronic phase. After infection with L. monocytogenes, LRG-47-deficient mice exhibited a profound loss of resistance, whereas IRG-47-deficient mice exhibited completely normal resistance. In addition, both strains displayed normal clearance of MCMV. Thus, LRG-47 and IRG-47 have vital, but distinct roles in immune defense against protozoan and bacterial infections.

Altered lymphocyte responses and cytokine production in mice deficient in the X-linked lymphoproliferative disease gene SH2D1A/DSHP/SAP.

We have introduced a targeted mutation in SH2D1A/DSHP/SAP, the gene responsible for the human genetic disorder X-linked lymphoproliferative disease (XLP). SLAM-associated protein (SAP)-deficient mice had normal lymphocyte development, but on challenge with infectious agents, recapitulated features of XLP. Infection of SAP- mice with lymphocyte choriomeningitis virus (LCMV) or Toxoplasma gondii was associated with increased T cell activation and IFN-gamma production, as well as a reduction of Ig-secreting cells. Anti-CD3-stimulated splenocytes from uninfected SAP- mice produced increased IFN-gamma and decreased IL-4, findings supported by decreased serum IgE levels in vivo. The Th1 skewing of these animals suggests that cytokine misregulation may contribute to phenotypes associated with mutation of SH2D1A/SAP.

Terphenyl ligand systems in lanthanide chemistry: use of the 2,6-di(1-naphthyl)phenyl ligand for the synthesis of kinetically stabilized complexes of trivalent ytterbium, thulium, and yttrium.

The molecular structures of terphenyl derivatives of trivalent ytterbium, thulium, and yttrium of general composition DnpLnCl(2)(THF)(2) [Dnp = 2,6-di(1-naphthyl)phenyl] are reported. The complexes (Ln = Yb: 1; Ln = Tm: 2; Ln = Y: 3) are synthesized by reaction of 1 equiv of DnpLi with 1 equiv of LnCl(3) (Ln = Yb, Tm, or Y) in tetrahydrofuran at room temperature in 50% yield. Attempts to prepare a Dnp scandium compound gave heterobimetallic [(THF)(3)Sc(2)OCl(5)Li(THF)](2) (4) in low yield. 1 crystallizes in the monoclinic space group C2/c. Crystal data for 1 at 203 K: a = 14.333(3) A, b = 16.353(3) A, c = 12.427(2) A, beta = 91.021(4) degrees, Z = 4, D(calcd) = 1.637 g cm(-3), R(1) = 4.44%. 2 crystallizes in the monoclinic space group C2/c. Crystal data for 2 at 203 K: a = 14.333(1) A, b = 16.374(2) A, c = 12.404(1) A, beta = 90.934(2) degrees, Z = 4, D(calcd) = 1.628 g cm(-3), R(1) = 3.00%. 3 crystallizes in the monoclinic space group C2/c. Crystal data for 3 at 203 K: a = 14.348(3) A, b = 16.476(3) A, c = 12.356(2) A, beta = 90.987(4) degrees, Z = 4, D(calcd) = 1.441 g cm(-3), R(1) = 5.62%. 4 crystallizes in the monoclinic space group P2(1)/n. Crystal data for 4 at 203 K: a = 11.0975(9) A, b = 11.0976(9) A, c = 21.3305(18) A, beta = 94.718(2) degrees, Z = 2, D(calcd) = 1.051 g cm(-3), R(1) = 3.45%. Complexes 1-3 represent examples of novel chiral (racemic) organometallic complexes of the lanthanide elements ytterbium and thulium and the group 3 element yttrium, respectively. The molecular structures of monomeric 1-3 exhibit distorted trigonal-bipyramidal coordination environments at the metal center, with the two oxygen atoms of the tetrahydrofuran ligands occupying the axial positions of a trigonal-bipyramidal coordination polyeder. The molecular structure of the scandium compound 4 shows a complex polynuclear heterobimetallic arrangement.

A heritable defect in IL-12 signaling in B10.Q/J mice. I. In vitro analysis.

B10.Q mice are normally susceptible to the induction of collagen-induced arthritis. We noted that one subline of B10.Q mice, B10.Q/J, was completely resistant to disease induction when immunized with collagen in CFA. B10.Q/J mice have a global defect in the generation of Th1 responses, and Ag-specific T cells derived from this strain failed to produce IFN-gamma. Because T cells from these mice could produce normal amounts of IFN-gamma when activated by IL-12/IL-18-independent stimuli, the defect appeared to be a failure to respond to IL-12. This defect extended to NK cells, which also failed to produce IFN-gamma when stimulated by IL-12. The capacity of NK cells, but not activated T cells, to produce IFN-gamma in response to IL-12 could be partially restored by IL-18. The expression of the IL-12R beta1- and beta2-chains on T cells and NK cells from B10.Q/J mice was normal. However, activated T cells from B10.Q/J mice did not signal normally through the IL-12R and manifested a defect in their capacity to phosphorylate Stat4. This defect was partial in that it could be overcome by increasing both the concentration of IL-12 and the incubation times in the Stat4 phosphorylation assays. Because Stat4 function is apparently intact in B10.Q/J mice, the defect in IL-12 signaling can be localized between the IL-12R complex and Stat4. This subtle abnormality in IL-12 responsiveness results in a profound defect in the generation of Th1 cells and the development of autoimmune disease.

A heritable defect in IL-12 signaling in B10.Q/J mice. II. Effect on acute resistance to Toxoplasma gondii and rescue by IL-18 treatment.

This study documents a defect in IL-12-dependent IFN-gamma responses in a substrain (B10.Q-H2-(q)/SgJ) of B10.Q mice that manifests as an acute susceptibility to infection by the intracellular protozoan pathogen, Toxoplasma gondii. Despite robust systemic production of IL-12, infected B10.Q/J animals fail to mount an early IFN-gamma response after parasite inoculation. Genetic experiments revealed that the host resistance and IFN-gamma production defects are determined by a single autosomal recessive locus distinct from the Stat4 gene. Nonetheless, a delayed IL-12-mediated IFN-gamma response emerges in later stages of acute infection but is unable to prevent host mortality. IL-18 administration restores, in an IL-12-dependent manner, the early IFN-gamma response and host resistance of B10.Q/J animals. These in vivo studies indicate that the partially impaired IL-12 responsiveness in B10.Q/J mice can result in defective host resistance and demonstrate a therapeutic function for IL-18 in reversing a genetically based immunodeficiency in IL-12-dependent IFN-gamma production.

A donor--acceptor--donor bridging ligand in a class III mixed-valence complex.

The novel mononuclear and dinuclear complexes [Ru(trpy)(bpy)(apc)][PF(6)] and [(Ru(trpy)(bpy))(2)(mu-adpc)][PF(6)](2) (bpy = 2,2'-bipyridine, trpy = 2,2':6',2' '-terpyridine, apc(-) = 4-azo(phenylcyanamido)benzene, and adpc(2)(-) = 4,4'-azodi(phenylcyanamido)) were synthesized and characterized by (1)H NMR, UV-vis, and cyclic voltammetry. Crystallography showed that the dinuclear Ru(II) complex crystallizes from diethyl ether/acetonitrile solution as [(Ru(trpy)(bpy))(2)(mu-adpc)][PF(6)](2).2(acetonitrile).2(diethyl ether). Crystal structure data are as follows: crystal system triclinic, space group P1, with a, b, and c = 12.480(2), 13.090(3) and 14.147(3) A, respectively, alpha, beta, and gamma = 79.792(3), 68.027(3), and 64.447(3) degrees, respectively, V = 1933.3(6) A(3), and Z = 1. The structure was refined to a final R factor of 0.0421. The mixed-valence complex with metal ions, separated by a through-space distance of 19.5 A, is a class III system, having the comproportionation constant K(c) = 1.3 x 10(13) and an intervalence band at 1920 nm (epsilon(max) = 10 000 M(-1) cm(-1)), in dimethylformamide solution. The results of this study strongly suggest that the bridging ligand adpc(2-) can mediate metal-metal coupling through both hole-transfer and electron-transfer superexchange mechanisms.

Inducible expression of Stat4 in dendritic cells and macrophages and its critical role in innate and adaptive immune responses.

Autocrine activation of APC by IL-12 has recently been revealed; we demonstrate here that inducible expression of Stat4 in APC is central to this process. Stat4 is induced in dendritic cells (DC) in a maturation-dependent manner and in macrophages in an activation-dependent manner. Stat4 levels directly correlate with IL-12-dependent IFN-gamma production by APC as well as IFN-gamma production by DC during Ag presentation. The Th2 cytokines IL-4 and IL-10 suppress Stat4 induction in DC and macrophages when present during maturation and activation, respectively, diminishing IFN-gamma production. In contrast, IL-4 has no effect on Stat4 levels in mature DC and actually augments IFN-gamma production by DC during Ag presentation, indicating that IL-4 acts differently in a spatiotemporal manner. The functional importance of Stat4 is evident in Stat4(-/-) DC and macrophages, which fail to produce IFN-gamma. Furthermore, Stat4(-/-) macrophages are defective in NO production in response to IL-12 and are susceptible to TOXOPLASMA: Autocrine IL-12 signaling is required for high-level IFN-gamma production by APC at critical stages in both innate and adaptive immunity, and the control of Stat4 expression is likely an important regulator of this process.

Reactivity of calix-tetrapyrrole SmII and SmIII complexes with acetylene: isolation of an "N-confused" calix-tetrapyrrole ring.

The nature of the substituents present on the calix-tetrapyrrole tetra-anion ligand [[R2C(C4H2N)]4]4- (R = [-(CH2)5-]0.5, Et) determines the type of reactivity of the corresponding SmII compounds with acetylene. With R = [-(CH2)5-]0.5, dehydrogenation occurred to yield the nearly colorless dinuclear diacetylide complex [[[[-(CH2)5-]4-calix-tetrapyrrole]SmIII]2(mu-C2Li4)].THF as the only detectable reaction product. Conversely, with R = Et, acetylene coupling in addition to dehydrogenation resulted in the formation of a dimeric butatrienediyl enolate derivative [[(Et8-calix-tetrapyrrole)SmIII[Li[Li(thf)]2(mu-OCH=CH2)]]2(mu,eta2,eta'2-HC=C=C=CH)]. Reaction of the trivalent hydride [(Et8-calix-tetrapyrrole)(thf)SmIII[(mu-H)[Li(thf)]]2 or of the terminally bonded methyl derivative [(Et8-calix-tetrapyrrole)(CH3)SmIII[[Li(thf)]2[Li(thf)2](mu3-Cl)]] with acetylene resulted in a mixture of the carbide [[(Et8-calix-tetrapyrrole)SmIII]2(mu-C2Li4)].Et2O with the dimerization product [[(Et8-calix-tetrapyrrole)SmIII[Li[Li(thf)]2(mu3-OCH=CH2)]]2-mu,eta2,eta'2-HC=C=C=CH)]. The same reaction also yielded a third product, a trivalent complex [[(Et8-calix-tetrapyrrole)SmIII[Li(thf)2]]2], in which the macrocycle was isomerized by shifting the ring attachment of one of the four pyrrole rings.