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1.
Jean L. Santos Paulo R. Yamasaki Chung Man Chin Célio H. Takashi Fernando R. Pavan Clarice Q.F. Leite 《Bioorganic & medicinal chemistry》2009,17(11):3795-3799
New phthalimide derivatives were easily prepared through condensation of phthalic anhydride and selected amines with variable yields (70–90%). All compounds (3a–l) were evaluated against Mycobacterium tuberculosis H37Rv using Alamar Blue susceptibility. The compounds 3c, 3i, and 3l have the minimum inhibitory concentrations (MICs) of 3.9, 7.8, and 5.0 μg/mL, respectively, and could be considered new lead compounds in the treatment of tuberculosis and multi-drug resistant tuberculosis. 相似文献
2.
Treatment of sea urchin eggs for 10 min prior to fertilization with the kinase inhibitor 6DMAP (6-dimethylaminopurine) reversibly inhibits swelling and loss of conical morphology of the male pronucleus. Male pronuclei inhibited with 1 mM 6DMAP for 25 min undergo phosphorylation of Sp H1 and Sp H2B histones as fully as do control nuclei. Therefore, Sp histone kinase, whose target sequences resemble those of the M-phase histone kinase, is not inhibited by 6DMAP, and Sp histone phosphorylation, although it may be necessary, is not sufficient for chromatin decondensation. 相似文献
3.
Ana Luiza Menegatti Pavan Maria Eugênia Dela Rosa Guilherme Giacomini Fernando Antonio Bacchim Neto Seizo Yamashita Luiz Carlos Vulcano Sergio Barbosa Duarte José Ricardo de Arruda Miranda Diana Rodrigues de Pina 《PloS one》2016,11(4)
Digital radiographic imaging is increasing in veterinary practice. The use of radiation demands responsibility to maintain high image quality. Low doses are necessary because workers are requested to restrain the animal. Optimizing digital systems is necessary to avoid unnecessary exposure, causing the phenomenon known as dose creep. Homogeneous phantoms are widely used to optimize image quality and dose. We developed an automatic computational methodology to classify and quantify tissues (i.e., lung tissue, adipose tissue, muscle tissue, and bone) in canine chest computed tomography exams. The thickness of each tissue was converted to simulator materials (i.e., Lucite, aluminum, and air). Dogs were separated into groups of 20 animals each according to weight. Mean weights were 6.5 ± 2.0 kg, 15.0 ± 5.0 kg, 32.0 ± 5.5 kg, and 50.0 ± 12.0 kg, for the small, medium, large, and giant groups, respectively. The one-way analysis of variance revealed significant differences in all simulator material thicknesses (p < 0.05) quantified between groups. As a result, four phantoms were constructed for dorsoventral and lateral views. In conclusion, the present methodology allows the development of phantoms of the canine chest and possibly other body regions and/or animals. The proposed phantom is a practical tool that may be employed in future work to optimize veterinary X-ray procedures. 相似文献
4.
Stefano Pavan Adalgisa Schiavulli Michela Appiano Cecilia Miacola Richard G. F. Visser Yuling Bai Concetta Lotti Luigi Ricciardi 《Molecular breeding : new strategies in plant improvement》2013,31(1):247-253
Powdery mildew is the most widespread disease of pea (Pisum sativum L.) and causes severe economic losses worldwide. Recessively inherited er1 powdery mildew resistance, successfully used for decades in pea breeding programs, has recently been shown to originate from the loss of function of the PsMLO1 gene. Five er1 alleles, each corresponding to a different PsMLO1 null mutation, have been characterized to date in pea germplasm. In order to aid er1 selection, we aimed to identify functional markers which target PsMLO1 polymorphisms directly responsible for the resistant phenotype. Highly informative cleaved amplified polymorphic sequence (CAPS), derived cleaved amplified polymorphic sequence (dCAPS), sequence tagged site (STS) and high-resolution melting (HRM) markers were developed which enable the selection of each of the five er1 alleles. Taken together, the results described here provide a powerful tool for breeders, overcoming limitations of previously reported er1-linked markers due to the occurrence of recombination with the resistance locus and/or the lack of polymorphism between parental genotypes. The HRM marker er1-5/HRM54 reported here, targeting a mutagenesis-induced er1 allele recently described by us, does not require manual processing after PCR amplification, and is therefore suitable for large-scale breeding programs based on high-throughput automated screening. 相似文献
5.
6.
Rogerio Faustino Ribeiro Jr Felipe F. Potratz Brunella M. M. Pavan Ludimila Forechi Filipe Lugon Moulin Lima Jonaina Fiorim Aurelia Araujo Fernandes Dalton Valentim Vassallo Ivanita Stefanon 《PloS one》2013,8(1)
Carvedilol has beneficial effects on cardiac function in patients with heart failure but its effect on ovariectomy-induced myocardial contractile dysfunction remains unclear. Estrogen deficiency induces myocardial contractile dysfunction and increases cardiovascular disease risk in postmenopausal women. Our aim was to investigate whether carvedilol, a beta receptor blocker, would prevent ovariectomy-induced myocardial contractile dysfunction. Female rats (8 weeks old) that underwent bilateral ovariectomy were randomly assigned to receive daily treatment with carvedilol (OVX+CAR, 20 mg/kg), placebo (OVX) and SHAM for 58 days. Left ventricle papillary muscle was mounted for isometric tension recordings. The inotropic response to Ca2+ (0.62 to 3.75 mM) and isoproterenol (Iso 10−8 to 10−2 M) were assessed. Expression of calcium handling proteins was measured by western blot analysis. Carvedilol treatment in the OVX animals: prevented weight gain and slight hypertrophy, restored the reduced positive inotropic responses to Ca2+ and isoproterenol, prevented the reduction in SERCA2a expression, abolished the increase in superoxide anion production, normalized the increase in p22phox expression, and decreased serum angiotensin converting enzyme (ACE) activity. This study demonstrated that myocardial contractile dysfunction and SERCA2a down regulation were prevented by carvedilol treatment. Superoxide anion production and NADPH oxidase seem to be involved in this response. 相似文献
7.
Laura L. Baxter Dawn E. Watkins‐Chow William J. Pavan Stacie K. Loftus 《Pigment cell & melanoma research》2019,32(3):348-358
Over the past century, studies of human pigmentary disorders along with mouse and zebrafish models have shed light on the many cellular functions associated with visible pigment phenotypes. This has led to numerous genes annotated with the ontology term “pigmentation” in independent human, mouse, and zebrafish databases. Comparisons among these datasets revealed that each is individually incomplete in documenting all genes involved in integument‐based pigmentation phenotypes. Additionally, each database contained inherent species‐specific biases in data annotation, and the term “pigmentation” did not solely reflect integument pigmentation phenotypes. This review presents a comprehensive, cross‐species list of 650 genes involved in pigmentation phenotypes that was compiled with extensive manual curation of genes annotated in OMIM, MGI, ZFIN, and GO. The resulting cross‐species list of genes both intrinsic and extrinsic to integument pigment cells provides a valuable tool that can be used to expand our knowledge of complex, pigmentation‐associated pathways. 相似文献
8.
Deletion of PsbM in tobacco alters the QB site properties and the electron flow within photosystem II 总被引:1,自引:0,他引:1
Umate P Schwenkert S Karbat I Dal Bosco C Mlcòchová L Volz S Zer H Herrmann RG Ohad I Meurer J 《The Journal of biological chemistry》2007,282(13):9758-9767
Photosystem II, the oxygen-evolving complex of photosynthetic organisms, includes an intriguingly large number of low molecular weight polypeptides, including PsbM. Here we describe the first knock-out of psbM using a transplastomic, reverse genetics approach in a higher plant. Homoplastomic Delta psbM plants exhibit photoautotrophic growth. Biochemical, biophysical, and immunological analyses demonstrate that PsbM is not required for biogenesis of higher order photosystem II complexes. However, photosystem II is highly light-sensitive, and its activity is significantly decreased in Delta psbM, whereas kinetics of plastid protein synthesis, reassembly of photosystem II, and recovery of its activity are comparable with the wild type. Unlike wild type, phosphorylation of the reaction center proteins D1 and D2 is severely reduced, whereas the redox-controlled phosphorylation of photosystem II light-harvesting complex is reversely regulated in Delta psbM plants because of accumulation of reduced plastoquinone in the dark and a limited photosystem II-mediated electron transport in the light. Charge recombination in Delta psbM measured by thermoluminescence oscillations significantly differs from the 2/6 patterns in the wild type. A simulation program of thermoluminescence oscillations indicates a higher Q(B)/Q(-)(B) ratio in dark-adapted mutant thylakoids relative to the wild type. The interaction of the Q(A)/Q(B) sites estimated by shifts in the maximal thermoluminescence emission temperature of the Q band, induced by binding of different herbicides to the Q(B) site, is changed indicating alteration of the activation energy for back electron flow. We conclude that PsbM is primarily involved in the interaction of the redox components important for the electron flow within, outward, and backward to photosystem II. 相似文献
9.
Background
Caenorhabditis elegans hermaphrodites are capable of producing hundreds of progeny. However, genetic and environmental factors can keep many animals from attaining their full reproductive potential. In these situations, efficient use of any functional gametes becomes more important for reproductive success. To learn about this aspect of C. elegans reproductive biology, we examined oocyte production and sperm utilization patterns in a unique collection of semi-fertile sperm function mutants. 相似文献10.