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1.
Sacramento Doralice Rodrigues Coelho Rosalie Reed Rodrigues Wigg Márcia Dutra Toledo Luna Linhares Luiz Fernando de Matos dos Santos Marta Gonçalves Azevedo Soares Semêdo Luzia Teixeira de Ribeiro da Silva Antonio Jorge 《World journal of microbiology & biotechnology》2004,20(3):225-229
A promising producer of bioactive compounds isolated from a Brazilian tropical soil was tested for its range of antimicrobial
activities. Strain 606, classified as Streptomyces sp., could not be identified up to species level, suggesting a possible new taxon. The supernatant and 10 extracts and fractions,
obtained by extraction and chromatographic techniques, presented antimicrobial activity using antibiograms. The methanolic
fraction was highly active against pathogenic bacteria, phytopathogenic fungi and the human pathogenic yeast Candida albicans. It also possessed high antiviral activity inhibiting the propagation of an acyclovir-resistant herpes simplex virus type
1 strain on HEp-2 cells at non-cytotoxic concentration. The strong cytotoxic effect suggests an antitumour action.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Rosalie J. Harris Callum Bryant Melinda A. Coleman Andrea Leigh Verónica F. Briceño Pieter A. Arnold Adrienne B. Nicotra 《Journal of phycology》2023,59(1):179-192
Foundation seaweed species are experiencing widespread declines and localized extinctions due to increased instability of sea surface temperature. Characterizing temperature thresholds are useful for predicting patterns of change and identifying species most vulnerable to extremes. Existing methods for characterizing seaweed thermal tolerance produce diverse metrics and are often time-consuming, making comparisons between species and techniques difficult, hindering insight into global patterns of change. Using three kelp species, we adapted a high-throughput method – previously used in terrestrial plant thermal biology – for use on kelps. This method employs temperature-dependent fluorescence (T–F0) curves under heating or cooling regimes to determine the critical temperature (Tcrit) of photosystem II (PSII), i.e., the breakpoint between slow and fast rise fluorescence response to changing temperature, enabling rapid assays of photosynthetic thermal tolerance using a standardized metric. This method enables characterization of Tcrit for up to 48 samples per two-hour assay, demonstrating the capacity of T–F0 curves for high-throughput assays of thermal tolerance. Temperature-dependent fluorescence curves and their derived metric, Tcrit, may offer a timely and powerful new method for the field of phycology, enabling characterization and comparison of photosynthetic thermal tolerance of seaweeds across many populations, species, and biomes. 相似文献
4.
Rosalie Crouch Michael Coffman 《Biochemical and biophysical research communications》1976,73(2):428-433
Both and , increased exposure to visible light decreases the regenerability of the visual pigment. Isolated opsin irradiated with increasing periods of white light decreased in pigment formation yields on combination with 9- or 11- retinal. The yield of regeneration of the visual pigment extracted from albino rats depended on the amount of light to which the animal had been exposed. Animals exposed to normal room light demonstrated lower regeneration yields than dark-reared animals, but these yields increased on dark adaption. Opsin from animals exposed to sunlamps did not regenerate any pigment. On dark adaption, the pigment yields increased but the opsin level remained below that for the control group. 相似文献
5.
Respondents to a respiratory survey of Berlin, New Hampshire, residents in 1961 have been studied to assess the relationship between co-operation and respiratory disease prevalence. Two hundred and forty-three unco-operative subjects, interviewed at home, had significantly more morning phlegm and a lower vital capacity than carefully matched subjects who attended the central clinic. Fifty-one volunteers had the same prevalence of respiratory disease symptoms and physiological abnormalities as carefully matched subjects drawn from a probability sample of the city.It is concluded that respiratory disease prevalence will be underestimated if calculated from studies of co-operative subjects who attend a clinic. Case-finding by respiratory disease screening clinics will also miss many persons who suffer from chronic bronchitis. 相似文献
6.
Marcella Willemsen Gabrielle Krebbers Marcel W. Bekkenk Marcel B.M. Teunissen Rosalie M. Luiten 《The journal of histochemistry and cytochemistry》2021,69(5):339
The Opal multiplex technique is an established methodology for the detection of multiple biomarkers in one section. The protocol encompasses iterative single stainings and heating-mediated removal of the primary and secondary antibodies after each staining round, leaving untouched the Opal fluorophores which are deposited onto the antigen of interest. According to our experience, repetitive heating of skin sections often results in tissue damage, indicating an urgent need for milder alternatives to strip immunoglobulins. In this study, we demonstrate that considerable heating-related damage was found not only in skin but also in tissues of different origin, mostly characterized by low cell density. Importantly, the morphology remained fully intact when sections were repetitively exposed to β-mercaptoethanol-containing stripping buffer instead of multiple heating cycles. However, target epitopes appeared sensitive at a differential degree to multiple treatments with stripping buffer, as shown by loss in staining intensity, but in all cases, the staining intensity could be restored by increment of the primary antibody concentrations. Application of β-mercaptoethanol-containing stripping buffer instead of heating for antibody removal markedly improved the quality of the Opal multiplex technique, as a substantial higher number of differently colored cells could be visualized within a well-conserved morphological context: 相似文献
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Morgane Ollivier Anne Tresset Christophe Hitte Coraline Petit Sandrine Hughes Benjamin Gillet Marilyne Duffraisse Maud Pionnier-Capitan Laetitia Lagoutte Rose-Marie Arbogast Adrian Balasescu Adina Boroneant Marjan Mashkour Jean-Denis Vigne Catherine H?nni 《PloS one》2013,8(10)
We have used a paleogenetics approach to investigate the genetic landscape of coat color variation in ancient Eurasian dog and wolf populations. We amplified DNA fragments of two genes controlling coat color, Mc1r (Melanocortin 1 Receptor) and CBD103 (canine-β-defensin), in respectively 15 and 19 ancient canids (dogs and wolf morphotypes) from 14 different archeological sites, throughout Asia and Europe spanning from ca. 12 000 B.P. (end of Upper Palaeolithic) to ca. 4000 B.P. (Bronze Age). We provide evidence of a new variant (R301C) of the Melanocortin 1 receptor (Mc1r) and highlight the presence of the beta-defensin melanistic mutation (CDB103-K locus) on ancient DNA from dog-and wolf-morphotype specimens. We show that the dominant KB allele (CBD103), which causes melanism, and R301C (Mc1r), the variant that may cause light hair color, are present as early as the beginning of the Holocene, over 10 000 years ago. These results underline the genetic diversity of prehistoric dogs. This diversity may have partly stemmed not only from the wolf gene pool captured by domestication but also from mutations very likely linked to the relaxation of natural selection pressure occurring in-line with this process. 相似文献
9.
Rosalie Moody Ying Zhu Yufei Huang Xiaodong Cui Tiffany Jones Roble Bedolla Xiufen Lei Zhiqiang Bai Shou-Jiang Gao 《PLoS pathogens》2013,9(12)
Kaposi''s sarcoma-associated herpesvirus (KSHV) is causally linked to several human cancers, including Kaposi''s sarcoma, primary effusion lymphoma and multicentric Castleman''s disease, malignancies commonly found in HIV-infected patients. While KSHV encodes diverse functional products, its mechanism of oncogenesis remains unknown. In this study, we determined the roles KSHV microRNAs (miRs) in cellular transformation and tumorigenesis using a recently developed KSHV-induced cellular transformation system of primary rat mesenchymal precursor cells. A mutant with a cluster of 10 precursor miRs (pre-miRs) deleted failed to transform primary cells, and instead, caused cell cycle arrest and apoptosis. Remarkably, the oncogenicity of the mutant virus was fully restored by genetic complementation with the miR cluster or several individual pre-miRs, which rescued cell cycle progression and inhibited apoptosis in part by redundantly targeting IκBα and the NF-κB pathway. Genomic analysis identified common targets of KSHV miRs in diverse pathways with several cancer-related pathways preferentially targeted. These works define for the first time an essential viral determinant for KSHV-induced oncogenesis and identify NF-κB as a critical pathway targeted by the viral miRs. Our results illustrate a common theme of shared functions with hierarchical order among the KSHV miRs. 相似文献