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1.
P Deberghes A M Betbeder F Boisard R Blanc J F Delaby S Krivobok R Steiman F Seigle-Murandi EE Creppy 《Mycotoxin Research》1995,11(1):37-47
The toxicity of ochratoxin A (OTA), a mycotoxin produced by fungi ofAspergillus orPenicillium genera is now well documented. Its nephrotoxicity, immunosuppression, teratogenicity, and carcinogenicity have been widely studied. Physical and biochemical methods have been studied to prevent these toxinogenicAspergillus andPenicillium from producing OTA, and/or to destroy the mycotoxin when already produced in a liquid or a solid medium. Repeated freezing at ? 20?C and thawing at + 26?C aleatory reduce OTA production in a liquid medium. Exposure to UV B for different periods of time is efficient in preventing OTA production in a liquid medium. Gamma-irradiation from 2 to 5 kGy gives good results in preventing the production of OTA or destroying it when already produced. Carboxypeptidase is very efficient at 5 units/50 ml in a liquid medium for cleaving the OTA already produced. 相似文献
2.
AP Shoko SM Limbu HA Lamtane MA Kishe-Machumu B Sekadende EE Ulotu 《African Journal of Aquatic Science》2019,44(1):15-24
Aquaculture practices from sub-Saharan Africa are characterised by low production, owing to improper technology. Production can be increased through integrating fish farming with other existing on-farm activities, particularly livestock husbandry. We assessed the role of fish-poultry integration on all male Nile tilapia, Oreochromis niloticus growth performance, yields and economic benefits among smallholder farmers in sub-Saharan Africa, Tanzania. The study also compared phytoplankton species composition, abundance and biomass between the fish-poultry integration and non-integrated system. After 180 days of the experiment, all male O. niloticus cultured under fish-poultry integration exhibited significantly higher growth rates than those in the non-integrated system (p < 0.05). Gross fish yield (GFY), net fish yield (NFY) and net annual yields (NAY) obtained from fish-poultry integration were significantly higher than those from non-integrated system (p < 0.05). Partial enterprise budget analysis revealed that fish-poultry integration was more profitable than the non-integrated system. Moreover, fish-poultry integrated system produced significantly higher phytoplankton abundance and biomass than those from the non-integrated system. Results demonstrate that rural smallholder farmers can achieve higher growth rate, farm net yields and income by integrating all male O. niloticus with other on-farm activities than practising a stand-alone fish culture system. 相似文献
3.
Nuclear gene trees and the phylogenetic relationships of the mangabeys (Primates: Papionini) 总被引:3,自引:1,他引:2
Phylogenetic relationships of mangabeys within the Old World monkey tribe
Papionini are inferred from analyses of nuclear DNA sequences from five
unlinked loci. The following conclusions are strongly supported, based on
congruence among trees derived for the five separate gene regions: (1)
mangabeys are polyphyletic within the Papionini; (2) Cercocebus is the
sister taxon to the genus Mandrillus; and (3) Lophocebus belongs to a clade
with Papio and Theropithecus, with Papio as its most likely sister taxon.
Morphologically based phylogenies positing mangabey monophyly were
evaluated by mapping the sequences for each locus on these trees. The data
seem to fit these trees poorly in both maximum-parsimony and likelihood
analyses. Incongruence among nuclear gene trees occurred in the
interrelationships among Lophocebus, Papio, and Theropithecus. Several
factors that may account for this incongruence are discussed, including
sampling error, random lineage sorting, and introgression.
相似文献
4.
Differential roles of vascular endothelial growth factor receptors 1 and 2 in dendritic cell differentiation 总被引:13,自引:0,他引:13
Dikov MM Ohm JE Ray N Tchekneva EE Burlison J Moghanaki D Nadaf S Carbone DP 《Journal of immunology (Baltimore, Md. : 1950)》2005,174(1):215-222
Impaired Ag-presenting function in dendritic cells (DCs) due to abnormal differentiation is an important mechanism of tumor escape from immune control. A major role for vascular endothelial growth factor (VEGF) and its receptors, VEGFR1/Flt-1 and VEGFR2/KDR/Flk-1, has been documented in hemopoietic development. To study the roles of each of these receptors in DC differentiation, we used an in vitro system of myeloid DC differentiation from murine embryonic stem cells. Exposure of wild-type, VEGFR1(-/-), or VEGFR2(-/-) embryonic stem cells to exogenous VEGF or the VEGFR1-specific ligand, placental growth factor, revealed distinct roles of VEGF receptors. VEGFR1 is the primary mediator of the VEGF inhibition of DC maturation, whereas VEGFR2 tyrosine kinase signaling is essential for early hemopoietic differentiation, but only marginally affects final DC maturation. SU5416, a VEGF receptor tyrosine kinase inhibitor, only partially rescued the mature DC phenotype in the presence of VEGF, suggesting the involvement of both tyrosine kinase-dependent and independent inhibitory mechanisms. VEGFR1 signaling was sufficient for blocking NF-kappaB activation in bone marrow hemopoietic progenitor cells. VEGF and placental growth factor affect the early stages of myeloid/DC differentiation. The data suggest that therapeutic strategies attempting to reverse the immunosuppressive effects of VEGF in cancer patients might be more effective if they specifically targeted VEGFR1. 相似文献
5.
Sonia Baig Narasimhan Kothandaraman Jayapal Manikandan Li Rong Kim Huey EE Jeffrey Hill Chin Wee Lai Wan Yu Tan Felicia Yeoh Anita Kale Lin Lin Su Arijit Biswas Sheila Vasoo Mahesh Choolani 《Clinical proteomics》2014,11(1)
Background
Placental syncytiotrophoblast microvesicles (STBM) are shed into the maternal circulation during normal pregnancy. STBM circulate in significantly increased amounts in preeclampsia (PE) and are considered to be among contributors to the exaggerated proinflammatory, procoagulant state of PE. However, protein composition of STBM in normal pregnancy and PE remains unknown. We therefore sought to determine the protein components of STBM and whether STBM protein expressions differ in preeclamptic and normal pregnancies.Patients with PE (n = 3) and normal pregnant controls (n = 6) were recruited. STBM were prepared from placental explant culture supernatant. STBM proteins were analyzed by a combination of 1D Gel-LC-MS/MS. Protein expressions levels were quantified using spectral counts and validated by immunohistochemistry.Results
Over 400 proteins were identified in the STBM samples. Among these, 25 proteins were found to be differentially expressed in preeclampsia compared to healthy pregnant controls, including integrins, annexins and histones.Conclusion
STBM proteins include those that are implicated in immune response, coagulation, oxidative stress, apoptosis as well as lipid metabolism pathways. Differential protein expressions of STBM suggest their pathophysiological relevance in PE.Electronic supplementary material
The online version of this article (doi:10.1186/1559-0275-11-40) contains supplementary material, which is available to authorized users. 相似文献6.
Andrew Keith Watson Bernhard Kepplinger Sahar Mubarak Bakhiet Najwa Adam Mhmoud Jonathan Chapman Nick EE Allenby Katarzyna Mickiewicz Michael Goodfellow Ahmed Hassan Fahal Jeff Errington 《PLoS neglected tropical diseases》2022,16(7)
Mycetoma is a neglected tropical chronic granulomatous inflammatory disease of the skin and subcutaneous tissues. More than 70 species with a broad taxonomic diversity have been implicated as agents of mycetoma. Understanding the full range of causative organisms and their antibiotic sensitivity profiles are essential for the appropriate treatment of infections. The present study focuses on the analysis of full genome sequences and antibiotic inhibitory concentration profiles of actinomycetoma strains from patients seen at the Mycetoma Research Centre in Sudan with a view to developing rapid diagnostic tests. Seventeen pathogenic isolates obtained by surgical biopsies were sequenced using MinION and Illumina methods, and their antibiotic inhibitory concentration profiles determined. The results highlight an unexpected diversity of actinomycetoma causing pathogens, including three Streptomyces isolates assigned to species not previously associated with human actinomycetoma and one new Streptomyces species. Thus, current approaches for clinical and histopathological classification of mycetoma may need to be updated. The standard treatment for actinomycetoma is a combination of sulfamethoxazole/trimethoprim and amoxicillin/clavulanic acid. Most tested isolates had a high IC (inhibitory concentration) to sulfamethoxazole/trimethoprim or to amoxicillin alone. However, the addition of the β-lactamase inhibitor clavulanic acid to amoxicillin increased susceptibility, particularly for Streptomyces somaliensis and Streptomyces sudanensis. Actinomadura madurae isolates appear to have a particularly high IC under laboratory conditions, suggesting that alternative agents, such as amikacin, could be considered for more effective treatment. The results obtained will inform future diagnostic methods for the identification of actinomycetoma and treatment. 相似文献
7.
Y Deng J Zhao D Sakurai KM Kaufman JC Edberg RP Kimberly DL Kamen GS Gilkeson CO Jacob RH Scofield CD Langefeld JA Kelly ME Alarcón-Riquelme BIOLUPUS GENLES Networks JB Harley TJ Vyse BI Freedman PM Gaffney KM Sivils JA James TB Niewold RM Cantor W Chen BH Hahn EE Brown PROFILE BP Tsao 《Arthritis research & therapy》2012,14(Z3):A5
8.
Han BG Hao CM Tchekneva EE Wang YY Lee CA Ebrahim B Harris RC Kern TS Wasserman DH Breyer MD Qi Z 《American journal of physiology. Endocrinology and metabolism》2008,295(4):E981-E986
The present studies examined the relationship between fasting blood glucose and Hb A(1c) in C57BL/6J, DBA/2J, and KK/HlJ mice with and without diabetes mellitus. Daily averaged blood glucose levels based on continuous glucose monitoring and effects of 6-h vs. overnight fasting on blood glucose were determined. Daily averaged blood glucose levels were highly correlated with Hb A(1c), as determined with a hand-held automated device using an immunodetection method. R(2) values were 0.90, 0.95, and 0.99 in KK/HIJ, C57BL/6J, and DBA/2J, respectively. Six-hour fasting blood glucose correlated more closely with the level of daily averaged blood glucose and with Hb A(1c) than did blood glucose following an overnight fast. To validate the immunoassay-determined Hb A(1c), we also measured total glycosylated hemoglobin using boronate HPLC. Hb A(1c) values correlated well with total glycosylated hemoglobin in all three strains but were relatively lower than total glycosylated hemoglobin in diabetic DBA/2J mice. These results show that 6-h fasting glucose provides a superior index of glycemic control and correlates more closely with Hb A(1c) than overnight-fasted blood glucose in these strains of mice. 相似文献
9.
EE LIN LIM 《The Journal of eukaryotic microbiology》1996,43(2):101-106
Nanoplanktonic protists are comprised of a diverse assemblage of species which are responsible for a variety of trophic processes in marine and freshwater ecosystems. Current methods for identifying small protists by electron microscopy do not readily permit both identification and enumeration of nanoplanktonic protists in field samples. Thus, one major goal in the application of molecular approaches in protistan ecology has been the detection and quantification of individual species in natural water samples. Sequences of small subunit ribosomal RNA (SSU rRNA) genes have proven to be useful towards achieving this goal. Comparison of sequences from clone libraries of protistan SSU rRNA genes amplified from natural assemblages of protists by the polymerase chain reaction (PCR) can be used to examine protistan diversity. Furthermore, oligonucleotide probes complementary to short sequence regions unique to species of small protists can be designed by comparative analysis of rRNA gene sequences. These probes may be used to either detect the RNA of particular species of protists in total nucleic acid extracts immobilized on membranes, or the presence of target species in water samples via in situ hybridization of whole cells. Oligonucleotide probes may also serve as primers for the selective amplification of target sequences from total population DNA by PCR. Thus, molecular sequence information is becoming increasingly useful for identifying and enumerating protists, and for studying their spatial and temporal distribution in nature. Knowledge of protistan species composition, abundance and variability in an environment can ultimately be used to relate community structure to various aspects of community function and biogeochemical activity. 相似文献
10.
EE LIN LIM MARK R. DENNETT DAVID A. CARON 《The Journal of eukaryotic microbiology》2001,48(3):247-257
Thirty clones derived from twenty isolates of heterotrophic nanoflagellates originating from a variety of marine and freshwater environments were examined by restriction fragment length polymorphism analysis of small subunit ribosomal RNA genes amplified by the polymerase chain reaction (riboprinting). The data were compared with light and electron microscopical identification of the isolates. On morphological criteria, sixteen of the thirty clones belonged to the genus Paraphysomonas De Saedeleer, seven to the genus Spumella Cienkowski, four to the genus Pteridomonas Penard and three to the genus Cafeteria Fenchel and Patterson. Among these taxa, eleven ribotypes were detected by analysis with the restriction enzymes Hinf I, Hae III, Sau3A I, and Msp I. Differentiation of nanoflagellate taxa by the riboprinting method supported taxonomic classification based on morphology at the generic and species level. The utility of the method for discriminating the 'naked' flagellates and for confirming the identity of polymorphic forms among species of Paraphysomonas is demonstrated. 相似文献