94 research outputs found
Microwave treatment modify antigenicity properties of bovine milk proteins
This work is aimed to assess the effect of a microwave heating on cow’s milk protein antigenicity. The heating protocol is established on the power/time relationship. A first share of milk samples were treated at 300 and 400 watts for 10, 15 and 20 min. The second share of milk and whey samples weretreated at 500, 600 and 700 watts for 10 min. The antigenicity of proteins is evaluated by a study of milk sample reactivity towards the IgG anti--Lg (obtained from immunized rabbits) using ELISA method. Microwave treatment of whole milk cause significant decrease of whey proteins concentration thansamples of fresh whey treated. Electrophoresis analysis reveals that whole milk treated by microwave induces more changes in whey proteins composition. Microwave heating of entire cow’s milk seems to diminish its whey proteins reactivity towards the specific antibodies (IgG)
New N-Alkylated Heterocyclic Compounds as Prospective NDM1 Inhibitors : Investigation of In Vitro and In Silico Properties
A new family of pyrazole-based compounds (1-15) was synthesized and characterized using different physicochemical analyses, such as FTIR, UV-Visible, H-1, C-13 NMR, and ESI/LC-MS. The compounds were evaluated for their in vitro antifungal and antibacterial activities against several fungal and bacterial strains. The results indicate that some compounds showed excellent antibacterial activity against E. coli, S. aureus, C. freundii, and L. monocytogenes strains. In contrast, none of the compounds had antifungal activity. Molecular electrostatic potential (MEP) map analyses and inductive and mesomeric effect studies were performed to study the relationship between the chemical structure of our compounds and the biological activity. In addition, molecular docking and virtual screening studies were carried out to rationalize the antibacterial findings to characterize the modes of binding of the most active compounds to the active pockets of NDM1 proteins.Peer reviewe
Plant growth promoting activities of Pseudomonas sp. and Enterobacter sp. isolated from the rhizosphere of Vachellia gummifera in Morocco
The Moroccan endemic Vachellia gummifera grows wild under extreme desert conditions. This plant could be used as an alternative fodder for goats, and camels, in order to protect the Argan forests against overgrazing in Central and Southwestern Moroccan semiarid areas. With the aim to improve the V. gummifera population's density in semiarid areas, we proposed its inoculation with performing plant growth-promoting bacteria. Hence, 500 bacteria were isolated from the plant rhizosphere. From these, 291 isolates were retained for plant growth-promoting (PGP) activities assessment. A total of 44 isolates showed the best phosphates solubilization potential, as well as siderophore and auxin production. The combination of REP-PCR (repetitive extragenic palindromic-polymerase chain reaction) fingerprinting, PGP activities, and phenotypic properties, allowed the selection of three strains for the inoculation experiments. The three selected strains' 16S rRNA sequencing showed that they are members of the Enterobacter and Pseudomonas genera. The inoculation with three strains had diverse effects on V. gummifera growth parameters. All single and combined inoculations improved the plant shoot weight by more than 200%, and the root length by up to 139%, while some combinations further improved protein and chlorophyll content, thereby improving the plant's forage value. The three selected strains constitute an effective inoculum for use in the arid and semiarid zones of southern Morocco.The authors want to thank all the persons who contributed to the achievement of this work. This work was funded by the Hassan II Academy of Science and Technology (AH2ST), in Morocco. B.M. received a grant from the AH2ST. She received also the excellency fellowship Khadija Baddouri in life sciences, from the Horizons foundation, Franc
Different species of Bradyrhizobium from symbiovars genistearum and retamae nodulate the endemic Retama dasycarpa in the High Atlas Mountains
Retama dasycarpa is an endemic Retama species native to the cold semi-arid bioclimates of the High Atlas Mountains in Morocco. In this work, we analyzed the diversity of the microsymbionts nodulating this plant and their different phenotypic and symbiotic characteristics. Phylogenetic analysis of the 16S rRNA gene revealed that the tested isolates clustered in the Bradyrhizobium genus. Multilocus sequence analyses of four housekeeping genes (recA, gyrB, glnII and atpD) for 12 selected strains grouped them into four clusters close to B. lupini USDA 3051, B. frederickii CNPSo 3446, B. valentinum LmjM3 and B. retamae Ro19. The individual phylogenies of these core genes and the symbiotic genes nodC, nodA and nifH were congruent. These isolates showed a broad host range, being able to nodulate different legume hosts, such as R. sphaerocarpa, R. monosperma, Lupinus luteus, Cytisus grandiflorus and Chamaecytisus albidus, but not Phaseolus vulgaris or Glycine max. They all had a similar metabolic capacity, using the majority of the carbohydrates and amino acids tested as sole sources of carbon and nitrogen. Furthermore, out of the 12 selected strains, some displayed plant growth-promoting features, with six of them solubilizing phosphate and three of them producing siderophores. The present work provides, for the first time, a detailed description about the microsymbionts associated with the endemic legume R. dasycarpa.This work was supported by the Ministry of Higher Education and Innovation. Dr Mouad Lamrabet was granted a fellowship from the PPR2-BIOMIVER project. The authors want to thank all the
people who contributed to this work
Geometric least squares means ratios for the analysis of Plasmodium falciparum in vitro susceptibility to antimalarial drugs
<p>Abstract</p> <p>Background</p> <p>The susceptibility of microbes such as <it>Plasmodium falciparum </it>to drugs is measured in vitro as the concentration of the drug achieving 50% of maximum effect (IC<sub>50</sub>); values from a population are summarized as geometric means. For antimalarial drugs, as well as for antibiotics, assessing changes in microbe susceptibility over time under drug pressure would help inform treatment policy decisions, but no standard statistical method exists as yet.</p> <p>Methods</p> <p>A mixed model was generated on log<sub>e</sub>-transformed IC<sub>50 </sub>values and calculated geometric least squares means (GLSM) with 90% confidence intervals (CIs). In order to compare IC<sub>50</sub>s between years, GLSM ratios (GLSMR) with 90%CIs were calculated and, when both limits of the 90%CIs were below or above 100%, the difference was considered statistically significant. Results were compared to those obtained from ANOVA and a generalized linear model (GLM).</p> <p>Results</p> <p>GLSMRs were more conservative than ANOVA and resulted in lower levels of statistical significance. The GLSMRs approach allowed for random effect and adjustment for multiple comparisons. GLM was limited in the number of year-to-year comparisons by the need for a single reference year. The three analyses yielded generally consistent results.</p> <p>Conclusion</p> <p>A robust analytical method can palliate inherent limitations of in vitro sensitivity testing. The random effects GLSMRs with adjustment for multiple comparisons and 90%CIs require only assumptions on the mixed model to be applied. Results are easy to display graphically and to interpret. The GLMSRs should be considered as an option for monitoring changes in drug susceptibility of <it>P. falciparum </it>malaria and other microbes.</p
Modern microwave methods in solid state inorganic materials chemistry: from fundamentals to manufacturing
No abstract available
Sentinel network for monitoring in vitro susceptibility of Plasmodium falciparum to antimalarial drugs in Colombia: a proof of concept
Drug resistance is one of the principal obstacles blocking worldwide malaria control. In Colombia, malaria remains a major public health concern and drug-resistant parasites have been reported. In vitro drug susceptibility assays are a useful tool for monitoring the emergence and spread of drug-resistant Plasmodium falciparum. The present study was conducted as a proof of concept for an antimalarial drug resistance surveillance network based on in vitro susceptibility testing in Colombia. Sentinel laboratories were set up in three malaria endemic areas. The enzyme linked immunosorbent assay-histidine rich protein 2 and schizont maturation methods were used to assess the susceptibility of fresh P. falciparum isolates to six antimalarial drugs. This study demonstrates that an antimalarial drug resistance surveillance network based on in vitro methods is feasible in the field with the participation of a research institute, local health institutions and universities. It could also serve as a model for a regional surveillance network. Preliminary susceptibility results showed widespread chloroquine resistance, which was consistent with previous reports for the Pacific region. However, high susceptibility to dihydroartemisinin and lumefantrine compounds, currently used for treatment in the country, was also reported. The implementation process identified critical points and opportunities for the improvement of network sustainability strategies.PAHO [057-1-3144141]; COLCIENCIAS [ID 2229-405-20319]info:eu-repo/semantics/publishedVersio
Gender differences in the implementation of school-based assessment in a Malaysian state
This study aims to identify the differences in assessment knowledge, school support, teacher
readiness, teacher skills and challenges faced by male and female Grade 8 teachers who are involved
in implementing School-Based Assessment (SBA) and the interrelationship among these five factors.
In addition, this study explores the teachers’ views with regards to these five factors.This study uses a quantitative questionnaire designed by the researchers, and a total of 243 Grade 8 teachers answered the questionnaire.Qualitative data was then collected via semi-structured interviews which were conducted with 20 teachers. The findings show that male teachers are more ready to implement SBA compared to female teachers.Compared to the female teachers, the male teachers view school support as more important. In terms of knowledge, skills and challenges towards the implementation of SBA, there are no gender differences. The findings also show that there exist significant relationships among the five factors except between school support and challenges faced in SBA.Although male and female teachers share many similar views, the predominant view among female teachers when compared to the male teachers is that many challenges and issues need to be addressed in the implementation of SBA. The findings from the interviews also suggest that male teachers are more willing to accept changes when compared to the female teachers.This study has implications for the implementation of SBA in Malaysia because 63% of the teachers implementing SBA are females
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