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991.
Sakhanokho Hamidou F. Babiker Ebrahiem M. Smith Barbara J. Drackett Patricia R. 《Plant Cell, Tissue and Organ Culture》2019,137(3):637-637
Plant Cell, Tissue and Organ Culture (PCTOC) - There were two errors in the original publication: The copyright holder was specified as Springer Nature B.V. The correct information is as follows:... 相似文献
992.
Stacey A. Bryan Barbara I. P. Barratt Philip J. Seddon Yolanda van Heezik 《New Zealand journal of zoology.》2019,46(3):189-200
The Australian redback spider, Latrodectus hasseltii preys on at least 10 endemic species in New Zealand, highlighting a need for control. Male redbacks are attracted to virgin females by an airborne pheromone. The aim of this study was to analyse the response of male redback spiders to two volatile chemicals found on the silk of virgin but not mated females, to determine whether these compounds constitute components of the airborne pheromone. Mature male redback spiders were placed in an olfactometer where they had a choice of two stimuli. We compared their response to paired combinations of a control, virgin silk, butyric acid and isovaleric acid. Male redbacks responded equally strongly to butyric acid and virgin silk, in terms of time spent near the stimulus. The identification of butyric acid as a component of the airborne sex pheromone of L. hasseltii provides the groundwork for developing a pheromone-based control. 相似文献
993.
Fatima Amanat Shirin Strohmeier Philip S. Meade Nicholas Dambrauskas Barbara Mühlemann Derek J. Smith Vladimir Vigdorovich D. Noah Sather Lynda Coughlan Florian Krammer 《PLoS biology》2021,19(12)
Vaccines against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) have been highly efficient in protecting against Coronavirus Disease 2019 (COVID-19). However, the emergence of viral variants that are more transmissible and, in some cases, escape from neutralizing antibody responses has raised concerns. Here, we evaluated recombinant protein spike antigens derived from wild-type SARS-CoV-2 and from variants B.1.1.7, B.1.351, and P.1 for their immunogenicity and protective effect in vivo against challenge with wild-type SARS-CoV-2 in the mouse model. All proteins induced high neutralizing antibodies against the respective viruses but also induced high cross-neutralizing antibody responses. The decline in neutralizing titers between variants was moderate, with B.1.1.7-vaccinated animals having a maximum fold reduction of 4.8 against B.1.351 virus. P.1 induced the most cross-reactive antibody responses but was also the least immunogenic in terms of homologous neutralization titers. However, all antigens protected from challenge with wild-type SARS-CoV-2 in a mouse model.This study explores the immune response induced by wild type and variant SARS-CoV-2 spike proteins, and the protection that these immune responses provide against challenge with wild type virus in the mouse model. 相似文献
994.
Alison R. Mercer Barbara S. Kirchhof John G. Hildebrand 《Developmental neurobiology》1996,29(1):49-64
Cell culture experiments have been used to examine the effects of serotonin [5-hydroxytryptamine (5-HT)] on the morphological development of antennal lobe (AL) neurons in the brain of the sphinx moth, Manduca sexta. The majority of cells used in this study were from animals at stage 5 of the 18 stages of metamorphic adult development. 5-HT did not affect the survival of M. sexta AL neurons in culture, but did increase the numbers of cells displaying features characteristic of certain cell types. Three morphologically distinct cell types were examined in detail. The principal effect of 5-HT on these neurons was enhancement of cell growth. The magnitude of responses to this amine was cell-type specific. Site-specific responses to 5-HT were apparent also in one cell type. Our results suggest that the effects of 5-HT can change during the course of metamorphic development. These changes coincide temporally with the development of fast, sodium-based action potentials. © 1996 John Wiley & Sons, Inc. 相似文献
995.
996.
Zhi L Ringgenberg JD Edwards JP Tegley CM West SJ Pio B Motamedi M Jones TK Marschke KB Mais DE Schrader WT 《Bioorganic & medicinal chemistry letters》2003,13(12):2075-2078
A series of 1,2-dihydrochromeno[3,4-f]quinoline derivatives was synthesized and tested in biological assays to evaluate the nonsteroidal progesterone receptor modulator pharmacophore (4) as antiprogestins. A number of potent analogues were identified by modification of the substituents at the D-ring. 相似文献
997.
Nussbaumer P Geyl D Horvath A Lehr P Wolff B Billich A 《Bioorganic & medicinal chemistry letters》2003,13(21):3673-3677
Steroid sulfatase (STS) has emerged as an attractive target for a range of estrogen- and androgen-dependent diseases. Searching for novel chemotypes as STS inhibitors, we identified nortropinyl-arylsulfonylurea 3 as a hit from high-throughput screening. A series of analogues was prepared in order to explore the essential structural elements for STS inhibition, and first structure-activity relationships were established. Mechanistic investigations revealed that the compounds are reversible, competitive inhibitors of STS. 相似文献
998.
Nayernia K Vauti F Meinhardt A Cadenas C Schweyer S Meyer BI Schwandt I Chowdhury K Engel W Arnold HH 《The Journal of biological chemistry》2003,278(48):48377-48385
Lis1 protein is the non-catalytic component of platelet-activating factor acetylhydrolase 1b (PAF-AH 1B) and associated with microtubular structures. Hemizygous mutations of the LIS1 gene cause type I lissencephaly, a brain abnormality with developmental defects of neuronal migration. Lis1 is also expressed in testis, but its function there has not been determined. We have generated a mouse mutant (LIS1GT/GT) by gene trap integration leading to selective disruption of a Lis1 splicing variant in testis. Homozygous mutant males are infertile with no other apparent phenotype. We demonstrate that Lis1 is predominantly expressed in spermatids, and spermiogenesis is blocked when Lis1 is absent. Mutant spermatids fail to form correct acrosomes and nuclei appear distorted in size and shape. The tissue architecture in mutant testis appears severely disturbed displaying collapsed seminiferous tubules, mislocated germ cells, and increased apoptosis. These results provide evidence for an essential and hitherto uncharacterized role of the Lis1 protein in spermatogenesis, particularly in the differentiation of spermatids into spermatozoa. 相似文献
999.
Luciana Gabriel Nogueira Ronaldo Honorato Barros Santos Barbara Maria Ianni Alfredo Inácio Fiorelli Eliane Conti Mairena Luiz Alberto Benvenuti Amanda Frade Eduardo Donadi Fabrício Dias Bruno Saba Hui-Tzu Lin Wang Abilio Fragata Marcelo Sampaio Mario Hiroyuki Hirata Paula Buck Charles Mady Edimar Alcides Bocchi Noedir Antonio Stolf Jorge Kalil Edecio Cunha-Neto 《PLoS neglected tropical diseases》2012,6(10)
Background
Chronic Chagas cardiomyopathy (CCC), a life-threatening inflammatory dilated cardiomyopathy, affects 30% of the approximately 8 million patients infected by Trypanosoma cruzi. Even though the Th1 T cell-rich myocarditis plays a pivotal role in CCC pathogenesis, little is known about the factors controlling inflammatory cell migration to CCC myocardium.Methods and Results
Using confocal immunofluorescence and quantitative PCR, we studied cell surface staining and gene expression of the CXCR3, CCR4, CCR5, CCR7, CCR8 receptors and their chemokine ligands in myocardial samples from end-stage CCC patients. CCR5+, CXCR3+, CCR4+, CCL5+ and CXCL9+ mononuclear cells were observed in CCC myocardium. mRNA expression of the chemokines CCL5, CXCL9, CXCL10, CCL17, CCL19 and their receptors was upregulated in CCC myocardium. CXCL9 mRNA expression directly correlated with the intensity of myocarditis, as well as with mRNA expression of CXCR3, CCR4, CCR5, CCR7, CCR8 and their ligands. We also analyzed single-nucleotide polymorphisms for genes encoding the most highly expressed chemokines and receptors in a cohort of Chagas disease patients. CCC patients with ventricular dysfunction displayed reduced genotypic frequencies of CXCL9 rs10336 CC, CXCL10 rs3921 GG, and increased CCR5 rs1799988CC as compared to those without dysfunction. Significantly, myocardial samples from CCC patients carrying the CXCL9/CXCL10 genotypes associated to a lower risk displayed a 2–6 fold reduction in mRNA expression of CXCL9, CXCL10, and other chemokines and receptors, along with reduced intensity of myocarditis, as compared to those with other CXCL9/CXCL10 genotypes.Conclusions
Results may indicate that genotypes associated to reduced risk in closely linked CXCL9 and CXCL10 genes may modulate local expression of the chemokines themselves, and simultaneously affect myocardial expression of other key chemokines as well as intensity of myocarditis. Taken together our results may suggest that CXCL9 and CXCL10 are master regulators of myocardial inflammatory cell migration, perhaps affecting clinical progression to the life-threatening form of CCC. 相似文献1000.