The Potential Link Between Pfas And Colorectal Cancer: A Narrative Review

Background: Currently, there is information on the detrimental impacts of exposure to pollutants such as per- and polyfluoroalkyl substances (PFAS) but there is still limited information on the impact PFAS has on colorectal cancer.Aim: To review and examine the evidence available in the existing published literature showing an association between exposure to PFAS and colorectal cancer. Methods: In this narrative review using searches of PubMed, SCOPUS and Google Scholar, publications between 2003 and 2023 were identified to ensure the inclusion of all recent development in this area of research. Inclusion criteria included a focus on the association between PFAS/PFOS and colorectal cancer. Both epidemiological and toxicology studies conducted globally were examined as well as reviews. In addition, studies that assessed an association between PFAS/PFOS and GI tract/intestinal inflammation were also reviewed, because they were considered relevant for the colorectal cancer outcome. Results: In the 18 studies included in this review, there is not sufficient evidence to say that PFAS/PFOS causes colorectal cancer. Findings from the animal studies vary, showing negative associations, molecular disruptions and microbiota dynamics, as well as inverse associations between PFAS exposure and reduction of gastrointestinal tumors. Additional studies on colorectal cancer cell lines and metabolic remodeling of cells suggest limited evidence for an association between PFOA exposure and stimulation cell’s invasive ability and metabolism. The epidemiological studies also show complex and distinct findings suggesting the need for further research to establish an association between PFAS/PFOS exposure and colorectal cancer. Conclusion: The current existing body of published literature does not provide sufficient evidence to establish an association between exposure to PFAS/PFOS and colorectal cancer. Additional research is warranted to better understand the mechanisms through which PFAS/PFOS affect colorectal cancer

Cooperation of Uzbekistan With the USA and Pakistan in Solving Problems in Afghanistan

In this article, Uzbekistan's cooperation with the United States and Pakistan in solving the problems of the neighboring state of Afghanistan will be analyzed on the basis of the latest materials. Previously unannounced data will be provided. The main attention will be paid to the role of cooperation of these three states for Afghanistan

Funeral Rite Ritual Ceremonies Of The Bronze And Early Iron Age In The Zarafshan Oasis

The article for the first time brings into scientific circulation new archaeological materials of the Bronze Age, found during the exploration of the Zarafshan Valley. On the basis of modern radiocarbon analysis, the chronological date of the burials of the Andronovo culture has been clarified. It is noted that the pastoralists of the Afanesovo and Andronovo steppes and the bearers of the settled agricultural culture had long-standing cultural and economic ties in the funeral rite

Optimization of Reaction Conditions in the Production of Gadolinium Diethylenetriamine Pentaacetate-Folate

A previous study has performed the laboratory-scale synthesis and characterization of Gadolinium Diethylenetriaminepentaacetate-Folate. Some parameters associated with the synthesis have been defined. In current study was focused on establishment the parameters for scaling up the production of Gadolinium Diethylenetriaminepentaacetate-Folate as a targeted MRI contrast agent. For the purpose of subsequent scaling up the synthesis, the parameters particularly those determining the yield of the reaction product should be established. This report presents the use of The Placket Burman Design and the Response Surface Methodology in establishing the parameters. Thus, following the Placket Burman Design, a number of synthesis reactions were carried out, each with different reaction conditions, with respect to parameters to include: mole ratio of reactants (i.e mole of Gd3+ to DTPA-Folate), time of reaction, temperature, stirring rate, pH and solvent volume. Using this method, a conclusion could be drawn that the three factors were found to be significant. To get final conclusions on the optimal synthesis reaction conditions, the Response Surface Methodology was then applied. For this purpose, again, some synthesis reactions experiments were performed. These were done, in accordance to the Response Surface Methodology, verified by analysis of countour plots, helped to locate the optimal value of the factors. The resulted data showed that for optimal yield of the synthesis reaction there were three dominant parameters. They were mole ratio of reactants, stirring rate process, and the volume of water

Modeling the effects of high strain rate loading on RC columns using Arbitrary Lagrangian Eulerian (ALE) technique

In recent years, many studies have been conducted by governmental and nongovernmental organizations across the world in an attempt to better understand the effect of explosive loads on buildings in order to better design against specific threats. This study is intended to contribute to increase the knowledge about how explosions affect reinforced concrete (RC) columns. In this study, a nonlinear model is developed to study the blast response of RC columns subjected to explosive loads. Numerical modeling of RC column under explosive load is presented using advanced finite element code LS DYNA. The obtained numerical model is validated with the experimental test and the results are in substantial agreement with the experimental data. ALE method for blast analysis is presented in the current research. The effects of scaled distance on the damage profile of RC columns are investigated. The results demonstrate that the level of damage increased with describing the scaled distance. Also the results shown duration for the blast loading, and hence the impulse, varies with charge masses at the specified scaled distance. Higher magnitude charge masses produced longer blast loading durations than lower magnitude charge masses. This means that at the same scaled distance, a charge mass of higher magnitude produced a higher impulse than the lower magnitude charge mass. The findings of this research represent the scaled distance is an important parameter that should be taken into account when analyzing the behavior of RC columns under explosive effects. The data collected from this research are being used to improve the knowledge of how structures will respond to a blast event, and improve finite element models for predicting the blast performance of concrete structures.Peer Reviewe

Effect of Hydrolytic Enzymes Production by Diazotrophs and Urea Fertilization on Root Colonization and Growth of Rice (Oryza Sativa L.)

Production of hydrolytic enzyme by diazotrophs and their association with rice plant may increase the N2-fixing activity and subsequently plant growth. The ability to produce hydrolytic enzymes is an important mechanism of diazotrophs to enter the plant roots. Hydrolytic activities are important during colonization of the surface and interior of root by associative and endophytic diazotrophs. A series of experiments were conducted in laboratory and glasshouse conditions with the following objectives; (i) to screen for hydrolytic enzyme production in diazotrophs isolated from rice rhizosphere, (ii) to determine the effect of diazotrophs on hydrolytic enzyme activity, root colonization, root development and N2-fixing activity of rice, (iii) to determine the effect of urea-N on hydrolytic enzyme production, N uptake and growth of rice inoculated with diazotrophs. Twelve bacterial isolates were screened for the endoglucanase (EG) and endopolymethylgalacturonase (EPMG). The production of the hydrolytic enzymes, root colonization and root development of MR219 rice inoculated with selected diazotrophs (Sb34, Sb41 and Sb42) was determined in vitro. The effect of urea-N on production of these hydrolytic enzymes in rice inoculated with diazotrophs was evaluated under glasshouse condition. The inoculated (Sb42 strain) and non-inoculated plants were treated with three rates of urea-N (0, 30 and 60 kg/ha). Plants were harvested at 45 days after transplanting and analyzed for soluble protein content, specific enzymes activity, plant growth, concentration and uptake of N and photosynthetic activity. Results showed that nine out of 12 bacterial strains were positive with carboxymethyl cellulose (CMC) and pectin reactions as indicated by appearance of halo zone around the colonies. There was significant (P≤0.05) effect of different diazotrophic inoculation on the rice rhizosphere and endosphere populations. Populations of inoculated diazotrophs were found higher in the rhizosphere than the endosphere of rice. Inoculated plants showed significantly (P≤0.05) higher specific enzymes activity and soluble protein content compared to non-inoculated control. Inoculation significantly (P≤0.05) increased root growth of rice with substantial increases in root length, volume and surface area. Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM) observations revealed the ability of diazotrophs to colonize the surface and interior of roots. Glasshouse study showed that growth of rice was significantly (P≤0.05) affected by diazotrophs and urea-N application. Low availability of nitrogen in soil stimulated the bacterial activity. Application of urea at 30 and 60 kg N negatively affected the interaction between diazotroph and rice plants. Inoculated plants without urea-N showed significantly (P≤0.05) higher specific hydrolytic enzymes activity, soluble protein content, plant biomass, photosynthesis activity and N uptake compared to other treatments. In general, diazotrophs produced substantial amount of hydrolytic enzyme which can improve nitrogen fixing activity in inoculated plants. Colonization of diazotrophs on the surface and interior of rice root is important for nitrogen fixation and plant growth enhancement. The association of these diazotrophs with the plants significantly (P≤0.05) increased the production of hydrolytic enzymes in the root system which is an important mechanism for endophytic colonization and subsequently nitrogen fixation

Molecular Charaterisation of Salmonella Serovars Isolated from Poultry

Salmonellosis has received considerable amount of attention because public health concerns in third world and developing countries including Malaysia. In Malaysia, the incidence of non-typhoidal salmonellosis is relatively unknown and has not been given much attention. Data collec1ed shows that the incidence of Salmonella species iso1atcd from animals and food sources have increased in recent years especially from poultry sources. One hundred and fourty seven Salmonella isolates belonging to 14 serovars were examined in the present study. Molecular techniques namely random amplified polymorphic DNA-PCR (RAPD-PCR), enterobacterial repetitive intergenic consensus-PCR (ERlC-PCR), polymerase chain reaction-ribotyping and pulsed field gel electrophoresis (PFGE) were used to subtype all the 147 Salmonella isolates at strains leveL Among these techniques. RAPD-PCR was the most superior in distinguishing all Salmonella serovars, followed by PFGE, ERIC-PCR and PCR-ribotyping. The PCR-based methods offered several advan1:ages over PFGE due to its speed, economics, ease to perform, results can be generated within 24 hours and large of samples can be analysed. simultaneously. In contrast, PFGE method was technically tedious, demanding and time consuming. Extensive genetic polymorphism or diversity was observed among strains of Salmonella serovars. In molecular typing for epidemiological studies, the level of the percentage of similarity in cluster analysis is arbitrarily adopted based on the clustering of the strains analysed. In this study, 70% of similarity level was chosen to analyse results obtained in PCR-based and PFGE analysis. Cluster obtained by the peR-based and PFGE typing techniques showed some disagreements in discriminating strains. Several strains that have different RAPD patterns did not necessarily bad similar PFGE. ERIC or PCR-ribotyping patterns. From the present study, it can be concluded that, it is impossible to rely on a single method to determine genetic relatedness among Salmonella serovars for effective epidemiological studies. This study clearly suggests that only a combination of different techniques is able to provide a comprehensive epidemiology of Salmonella serovars, and thus the need for a careful selection of the typing techniques. It has been identify the DNA-based typing methods is most effective for epidemiological studies