219 research outputs found

    Axenic amastigote cultivation and in vitro development of Leishmania orientalis

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    Leishmania (Mundinia) orientalis is a recently described new species that causes leishmaniasis in Thailand. To facilitate characterization of this new species, an in vitro culture system to generate L. orientalis axenic amastigotes was developed. In vitro culture conditions of the axenic culture-derived amastigotes were optimized by manipulation of temperature and pH. Four criteria were used to evaluate the resulting L. orientalis axenic amastigotes, i.e., morphology, zymographic analysis of nucleases, cyclic transformation, and infectivity to the human monocytic cell line (THP-1) cells. Results revealed that the best culture condition for L. orientalis axenic amastigotes was Grace's insect medium supplemented with FCS 20%, 2% human urine, 1% BME vitamins, and 25 μg/ml gentamicin sulfate, pH 5.5 at 35 °C. For promastigotes, the condition was M199 medium, 10% FCS supplemented with 2% human urine, 1% BME vitamins, and 25 μg/ml gentamicin sulfate, pH 6.8 at 26 °C. Morphological characterization revealed six main stages of the parasites including amastigotes, procyclic promastigotes, nectomonad promastigotes, leptomonad promastigotes, metacyclic promastigotes, and paramastigotes. Also, changes in morphology during the cycle were accompanied by changes in zymographic profiles of nucleases. The developmental cycle of L. orientalis in vitro was complete in 12 days using both culture systems. The infectivity to THP-1 macrophages and intracellular growth of the axenic amastigotes was similar to that of THP-1 derived intracellular amastigotes. These results confirmed the successful axenic cultivation of L. orientalis amastigotes. The axenic amastigotes and promastigotes can be used for further study on infection in permissive vectors and animals

    Development of Leishmania orientalis in the sand fly Lutzomyia longipalpis (Diptera: Psychodidae) and the biting midge Culicoides soronensis (Diptera: Ceratopogonidae)

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    Leishmania (Mundinia) orientalis is a newly described species causing human leishmaniasis in Thailand whose natural vector is unknown. L. orientalis infections in sand flies and/or biting midges under laboratory conditions have not been previously investigated. In this study, the development of L. orientalis in two experimental vectors, Lutzomyia longipalpis sand flies and Culicoides sonorensis biting midges was investigated for the first time using light microscopy, scanning electron microscopy, and histological examination. The results showed that L. orientalis was unable to establish infection in Lu. longipalpis. No parasites were found in the sand fly gut 4 days post-infected blood meal (PIBM). In contrast, the parasite successfully established infection in C. sonorensis. The parasites differentiated from amastigotes to procyclic promastigotes in the abdominal midgut (AMG) on day 1 PIBM. On day 2 PIBM, nectomonad promastigotes were observed in the AMG and migrated to the thoracic midgut (TMG). Leptomonad promastigotes appeared at the TMG on day 3 PIBM. Clusters of leptomonad promastigotes and metacyclic promastigotes colonized around the stomodeal valve with the accumulation of a promastigote secretory gel-like material from day 3 PIBM onwards. Haptomonad-like promastigotes were observed from day 5 PIBM, and the proportion of metacyclic promastigotes reached 23% on day 7 PIBM. The results suggest that biting midges or other sand fly genera or species might be vectors of L. orientalis

    First isolation of Leishmania from Northern Thailand:case report, identification as Leishmania martiniquensis and phylogenetic position within the Leishmania enriettii complex

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    Since 1996, there have been several case reports of autochthonous visceral leishmaniasis in Thailand. Here we report a case in a 52-year-old Thai male from northern Thailand, who presented with subacute fever, huge splenomegaly and pancytopenia. Bone marrow aspiration revealed numerous amastigotes within macrophages. Isolation of Leishmania LSCM1 into culture and DNA sequence analysis (ribosomal RNA ITS-1 and large subunit of RNA polymerase II) revealed the parasites to be members of the Leishmania enriettii complex, and apparently identical to L. martiniquensis previously reported from the Caribbean island of Martinique. This is the first report of visceral leishmaniasis caused by L. martiniquensis from the region. Moreover, the majority of parasites previously identified as "L. siamensis" also appear to be L. martiniquensis

    The association of dyslexia and developmental speech and language disorder candidate genes with reading and language abilities in adults

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    Reading and language abilities are critical for educational achievement and success in adulthood. Variation in these traits is highly heritable, but the underlying genetic architecture is largely undiscovered. Genetic studies of reading and language skills traditionally focus on children with developmental disorders; however, much larger unselected adult samples are available, increasing power to identify associations with specific genetic variants of small effect size. We introduce an Australian adult population cohort (41.7–73.2 years of age, N = 1505) in which we obtained data using validated measures of several aspects of reading and language abilities. We performed genetic association analysis for a reading and spelling composite score, nonword reading (assessing phonological processing: a core component in learning to read), phonetic spelling, self-reported reading impairment and nonword repetition (a marker of language ability). Given the limited power in a sample of this size (~80% power to find a minimum effect size of 0.005), we focused on analyzing candidate genes that have been associated with dyslexia and developmental speech and language disorders in prior studies. In gene-based tests, FOXP2, a gene implicated in speech/language disorders, was associated with nonword repetition (p < .001), phonetic spelling (p = .002) and the reading and spelling composite score (p < .001). Gene-set analyses of candidate dyslexia and speech/language disorder genes were not significant. These findings contribute to the assessment of genetic associations in reading and language disorders, crucial for understanding their etiology and informing intervention strategies, and validate the approach of using unselected adult samples for gene discovery in language and reading

    Analysis of Leishmania mimetic neoglycoproteins for the cutaneous leishmaniasis diagnosis

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    Oligosaccharides are broadly present on Leishmania cell surfaces. They can be useful for the leishmaniases diagnosis and also helpful in identifying new cell markers for the disease. The disaccharide Galα1-3Galβ is the immunodominant saccharide in Leishmania cell surface and is the unique non-reducing terminal glycosphingolipids structure recognized by anti-α-Gal. This study describes an enzyme-linked immunosorbent assay (ELISA) used to measure serum levels of anti-α-galactosyl (α-Gal) antibodies in patients with cutaneous leishmaniasis (CL). Optimal ELISA conditions were established and two neoglycoproteins (NGP) containing the Galα1-3Gal terminal fraction (Galα1-3Galβ1-4GlcNAc-HAS and Galα1-3Gal-HAS) and one Galα1-3Gal NGP analogue (Galα1-3Galβ1-3GlcNAc-HAS) were used as antigens. Means of anti-α-Gal antibody titres of CL patients were significantly higher (P < 0.05) than the healthy individuals for all NGPs tested. Sensitivity and specificity of all NGPs ranged from 62.2 to 78.4% and 58.3 to 96.7%, respectively. In conclusion, the NGPs can be used for CL diagnosis

    Production of a kinesin-related recombinant protein (Lbk39) from Leishmania braziliensis by Leishmania tarentolae promastigotes and its application in the serodiagnosis of leishmaniasis

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    The leishmaniases are multifactorial zoonotic diseases requiring a multidisciplinary One Health approach for diagnosis and control. For leishmaniasis diagnosis, here we describe production of a new recombinant protein based on a kinesin-related gene of Leishmania braziliensis (Lbk39), which shows 59% amino acid identity to the L. infantum homologue. The Lbk39 gene was synthesized, inserted into the pLEXSY-sat2 vector and transfected into L. tarentolae cells by electroporation. Culturing was carried out, and the secreted recombinant protein with a C-terminal histidine tag purified using nickel affinity chromatography on the culture supernatant, yielding a final product at 0.4 mg/mL. An indirect enzyme linked immunosorbent assay (ELISA) was standardised using sera from 74 Brazilian patients with cutaneous leishmaniasis and 11 with visceral leishmaniasis. Optimal ELISA conditions were established for the Lbk39 antigen in comparison with a crude extract from L. braziliensis. The sensitivity, specificity analysis and receiver operating characteristic (ROC) curve were determined with a significance level of 5%. The ROC curve showed a good accuracy with an area under curve (AUC) = 0.967, p < 0.001 (0.941–0.993) for CL patients and an AUC = 100 (100-100) for VL patients. The values of sensitivity and specificity were 88 and 98% for CL and 100 and 100% for VL, respectively. The study showed good production and expression of the target protein and has generated a potential new antigen for the diagnosis of leishmaniasis

    Genome-wide screening for DNA variants associated with reading and language traits

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    This research was funded by: Max Planck Society, the University of St Andrews - Grant Number: 018696, US National Institutes of Health - Grant Number: P50 HD027802, Wellcome Trust - Grant Number: 090532/Z/09/Z, and Medical Research Council Hub Grant Grant Number: G0900747 91070Reading and language abilities are heritable traits that are likely to share some genetic influences with each other. To identify pleiotropic genetic variants affecting these traits, we first performed a genome‐wide association scan (GWAS) meta‐analysis using three richly characterized datasets comprising individuals with histories of reading or language problems, and their siblings. GWAS was performed in a total of 1862 participants using the first principal component computed from several quantitative measures of reading‐ and language‐related abilities, both before and after adjustment for performance IQ. We identified novel suggestive associations at the SNPs rs59197085 and rs5995177 (uncorrected P ≈ 10–7 for each SNP), located respectively at the CCDC136/FLNC and RBFOX2 genes. Each of these SNPs then showed evidence for effects across multiple reading and language traits in univariate association testing against the individual traits. FLNC encodes a structural protein involved in cytoskeleton remodelling, while RBFOX2 is an important regulator of alternative splicing in neurons. The CCDC136/FLNC locus showed association with a comparable reading/language measure in an independent sample of 6434 participants from the general population, although involving distinct alleles of the associated SNP. Our datasets will form an important part of on‐going international efforts to identify genes contributing to reading and language skills.Publisher PDFPeer reviewe

    Deconvoluting kinase inhibitor induced cardiotoxicity

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    Many drugs designed to inhibit kinases have their clinical utility limited by cardiotoxicity-related label warnings or prescribing restrictions. While this liability is widely recognized, designing safer kinase inhibitors (KI) requires knowledge of the causative kinase(s). Efforts to unravel the kinases have encountered pharmacology with nearly prohibitive complexity. At therapeutically relevant concentrations, KIs show promiscuity distributed across the kinome. Here, to overcome this complexity, 65 KIs with known kinome-scale polypharmacology profiles were assessed for effects on cardiomyocyte (CM) beating. Changes in human iPSC-CM beat rate and amplitude were measured using label-free cellular impedance. Correlations between beat effects and kinase inhibition profiles were mined by computation analysis (Matthews Correlation Coefficient) to identify associated kinases. Thirty kinases met criteria of having (1) pharmacological inhibition correlated with CM beat changes, (2) expression in both human-induced pluripotent stem cell-derived cardiomyocytes and adult heart tissue, and (3) effects on CM beating following single gene knockdown. A subset of these 30 kinases were selected for mechanistic follow up. Examples of kinases regulating processes spanning the excitation–contraction cascade were identified, including calcium flux (RPS6KA3, IKBKE) and action potential duration (MAP4K2). Finally, a simple model was created to predict functional cardiotoxicity whereby inactivity at three sentinel kinases (RPS6KB1, FAK, STK35) showed exceptional accuracy in vitro and translated to clinical KI safety data. For drug discovery, identifying causative kinases and introducing a predictive model should transform the ability to design safer KI medicines. For cardiovascular biology, discovering kinases previously unrecognized as influencing cardiovascular biology should stimulate investigation of underappreciated signaling pathways

    The Vehicle, Spring 1985

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    Vol. 26, No. 2 Table of Contents Beyond the FieldsKeila Tooleypage 3 Lonely Sculptor Accustomed to Living AloneMichelle Mitchellpage 4 Mona LisaBob Zordanipage 4 Poet Born in Pearl HarborAngelique Jenningspage 5 IntroductionsGraham Lewispage 6 Living InsideJennifer Soulepage 9 PictureKathy Greypage 10 Salvadore Dali in a Wheelchair on TVAngelique Jenningspage 11 Sonata in E FlatBecky Lawsonpage 12 Myopia and Wild KingdomMichelle Mitchellpage 12 On Becoming a GrandmotherKeila Tooleypage 13 A VisionJennifer D. Pringlepage 14 The Covered BridgeDebbie Woodleypage 14 Jacob\u27s LifeJoan Sebastianpage 15 ForgotGraham Lewispage 15 A Dozen and One TrainsongsAngelique Jenningspage 16 Women\u27s PlaceJennifer Soulepage 19 Night SailingKim Dumentatpage 20 She Isn\u27t There WhenMichelle Mitchellpage 20 A Case for the Common ColdMaggie Kennedypage 21 the cityTammy Batespage 22 The RattlesnakeEric S. McGeepage 22 New PictureKeila Tooleypage 23 Lewis and SinGraham Lewispage 24 Funny BarbecueBob Zordanipage 26 In a DreamF. Link Rapierpage 26 The Winter\u27s ColdJennifer Soulepage 27 Diary EntryTammy Batespage 27 Minor God and Patron Saint of Rabbits SpeaksAngelique Jenningspage 28 A MomentBrett Wilhelmpage 29 The Bishop SeatF. Link Rapierpage 30 The Thought of Being Rid of MyselfKeila Tooleypage 33 I Saw A ChildBea Cessnapage 33 Complacent gourmetGary Burrowspage 34 Night DreamsJennifer Soulepage 35 Changing ImagesAmy Callpage 35 Olsen Rug Co. Waterfall & ParkMaggie Kennedypage 36 Edge of the WildF. Link Rapierpage 37 DragonS. Hillpage 37 Harvests of CornBob Zordanipage 38 The Club JeromeGary Burrowspage 39 Tarzan And The CabPatrick Peterspage 39 The Rain That Never CameLynanne Feilenpage 40 Wonderment of the Far CrescentF. Link Rapierpage 40https://thekeep.eiu.edu/vehicle/1047/thumbnail.jp
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