693 research outputs found
Ethoxyquin Inhibits the Progression of Murine Ehrlich Ascites Carcinoma through the Inhibition of Autophagy and LDH
Cancer cells exhibit an increased glycolysis rate for ATP generation (the Warburg effect) to sustain an increased proliferation rate. In tumor cells, the oxidation of pyruvate in the Krebs cycle is substituted by lactate production, catalyzed by LDH. In this study, we use ethoxyquin (EQ) as a novel inhibitor to target LDH in murine Ehrlich ascites carcinoma (EAC) and as a combination therapy to improve the therapeutic efficacy of the conventional chemotherapy drug, cisplatin (CIS). We investigated the anti-tumor effect of EQ on EAC-bearing mice and checked whether EQ can sustain the anti-tumor potential of CIS and whether it influences LDH activity. Treatment with EQ had evident anti-tumor effects on EAC as revealed by the remarkable decrease in the expression of the anti-apoptotic gene Bcl-2 and by a significant increase in the expression of apoptotic genes (BAX and caspase-3). EQ also caused a significant decrease in the autophagic activity of EAC cells, as shown by a reduction in the fluorescence intensity of the autophagosome marker. Additionally, EQ restored the altered hematological and biochemical parameters and improved the disrupted hepatic tissues of EAC-bearing mice. Co-administration of EQ and CIS showed the highest anti-tumor effect against EAC. Collectively, our findings propose EQ as a novel inhibitor of LDH in cancer cells and as a combinatory drug to increase the efficacy of cisplatin. Further studies are required to validate this therapeutic strategy in different cancer models and preclinical trials
Genetic variation among Northern and Southern Egyptian buffaloes using polymerase chain reaction-random amplified polymorphic DNA (PCR-RAPD)
The domestic water buffalo is a species of great economic potential, especially in developing countries like Egypt. Egyptian buffalo have been classified according to minor phenotypic differences and their geographical locations. Few studies have taken place to investigate the genetic variations in Egyptian buffalo using microsatellites analysis. In the present study, 11 random primers were analyzed for the genetic diversity determination between Northern and Southern Egyptian buffaloes using polymerase chain reaction-random amplified polymorphic DNA (PCR-RAPD) analysis. 169 bands were amplified for the analyzed 11 random primers, from which 160 bands (94.67%) for North populations and 168 bands for South population (99.41%). Out of the 160 amplified bands in North populations, 152 bands were polymorphic with a percentage of 89.94% and only one specific band (0.59%). In South population, all 168 amplified bands were polymorphic, nine bands (5.33%) were specific for this population. The identity index and the genetic distance between North and South populations were measured. The results showed that the two tested populations have the same origin and belong to one breed without significant genetic difference between their animals.Key words: Buffalo, genetic diversity, polymerase chain reaction (PCR), random amplified polymorphic DNA (RAPD)
Morphology and anatomical structure of the larval salt gland of Artemia tunisiana under different salinities
Brine shrimps of the genus Artemia is characterized by its high adaptability to adverse environmental conditions. To elucidate the effect of salinity on the neck organ (salt gland) of Artemia tunisiana nauplii, the morphology and fine structure of the ion transporting epithelium were examined following culturing under different salinities (25, 40, 70, 140 and 180 g/L). The expression of APH-1 mRNA, using semiquantitative reverse transcription-polymerase chain reaction (RT-PCR), was also determined. The morphology and anatomical structure of the salt gland varied according to the salinity degree. At low salinities, salt gland was small, thin and flat having many shallow canals, while at high salinities, it was more elongated with deeper canals and grooves. Ultrastructure examination showed low amplification of the plasma membrane at 25 g/L with no tubular tufts, while at 40 and 70 g/L salinities, the apical and central zones showed a large amplification of the surface area of the plasma membrane. At 140 g/L salinity, the epithelial cells were more elongated and the cuticle appeared to be composed of many layers. The general structure of the salt gland of nauplii cultured at 180 g/L disappeared. Semiquantitative APH-1 mRNA analysis indicated that the gene was expressed in all tested salinities. The expression did not change remarkably between 25 and 40 g/L salinities. As salinity increased, the gene was up regulated at 70 g/L and reached the highest level at 140 g/L, while the expression level reduced significantly at 180 g/L. This coincides with the histological results and highlights the possible role of APH-1 in salinity protection in Artemia.Keywords: Artemia, nauplii, salt gland, salinity, APH-1 gene expressionAfrican Journal of Biotechnology Vol. 12(41), pp. 6032-604
Investigation of pulse dispersion in a carrier-based UWB system with LO leakage cancellation
Local oscillator (LO) leakage in a carrier-based ultrawideband (UWB) system is a major design concern. In many cases, mixer LO-RF isolation is not sufficient and the LO leakage is well above the useful UWB signal. However, this leakage can be substantially reduced by using a notch filter located before the UWB transmitting antenna as long as it will not lead to unacceptable signal distortion. Therefore, various filter parameters, such as the filter order and 3 dB rejection bandwidth, have been studied to see their effects on providing sufficient band rejection level to reduce the unwanted LO leakage while minimizing the transmitted pulse dispersion. Time domain simulations and measurements have been utilized to evaluate the pulse dispersion using both the relative signal's first pulse amplitude and the pulse time delay spread. © 2009 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2009.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/64339/1/20390_ftp.pd
Characterization of the mrgRS locus of the opportunistic pathogen Burkholderia pseudomallei: temperature regulates the expression of a two-component signal transduction system
BACKGROUND: Burkholderia pseudomallei is a saprophyte in tropical environments and an opportunistic human pathogen. This versatility requires a sensing mechanism that allows the bacterium to respond rapidly to altered environmental conditions. We characterized a two-component signal transduction locus from B. pseudomallei 204, mrgR and mrgS, encoding products with extensive homology with response regulators and histidine protein kinases of Escherichia coli, Bordetella pertussis, and Vibrio cholerae. RESULTS: The locus was present and expressed in a variety of B. pseudomallei human and environmental isolates but was absent from other Burkholderia species, B. cepacia, B. cocovenenans, B. plantarii, B. thailandensis, B. vandii, and B. vietnamiensis. A 2128 bp sequence, including the full response regulator mrgR, but not the sensor kinase mrgS, was present in the B. mallei genome. Restriction fragment length polymorphism downstream from mrgRS showed two distinct groups were present among B. pseudomallei isolates. Our analysis of the open reading frames in this region of the genome revealed that transposase and bacteriophage activity may help explain this variation. MrgR and MrgS proteins were expressed in B. pseudomallei 204 cultured at different pH, salinity and temperatures and the expression was substantially reduced at 25°C compared with 37°C or 42°C but was mostly unaffected by pH or salinity, although at 25°C and 0.15% NaCl a small increase in MrgR expression was observed at pH 5. MrgR was recognized by antibodies in convalescent sera pooled from melioidosis patients. CONCLUSION: The results suggest that mrgRS regulates an adaptive response to temperature that may be essential for pathogenesis, particularly during the initial phases of infection. B. pseudomallei and B. mallei are very closely related species that differ in their capacity to adapt to changing environmental conditions. Modifications in this region of the genome may assist our understanding of the reasons for this difference
Plant Genome Engineering for Targeted Improvement of Crop Traits
To improve food security, plant biology research aims to improve crop yield and tolerance to biotic and abiotic stress, as well as increasing the nutrient contents of food. Conventional breeding systems have allowed breeders to produce improved varieties of many crops; for example, hybrid grain crops show dramatic improvements in yield. However, many challenges remain and emerging technologies have the potential to address many of these challenges. For example, site-specific nucleases such as TALENs and CRISPR/Cas systems, which enable high-efficiency genome engineering across eukaryotic species, have revolutionized biological research and its applications in crop plants. These nucleases have been used in diverse plant species to generate a wide variety of site-specific genome modifications through strategies that include targeted mutagenesis and editing for various agricultural biotechnology applications. Moreover, CRISPR/Cas genome-wide screens make it possible to discover novel traits, expand the range of traits, and accelerate trait development in target crops that are key for food security. Here, we discuss the development and use of various site-specific nuclease systems for different plant genome-engineering applications. We highlight the existing opportunities to harness these technologies for targeted improvement of traits to enhance crop productivity and resilience to climate change. These cutting-edge genome-editing technologies are thus poised to reshape the future of agriculture and food security
Perturbation of the metabolism of essential fatty acids by dietary partially hydrogenated vegetable oil.
Effect of Healthy Lifestyle Interventions in Schools of Jazan City, Kingdom of Saudi Arabia: A Quasi-experimental Study
Background
Unhealthy dietary habits and lifestyle among adolescents is considered as a risk factor for nutrition-related diseases in adulthood. The objective of this study was to investigate the effectiveness of a healthy lifestyle intervention—including physical activity (PA) and eating habits (EH)—among female students in Jizan City, southwest Kingdom of Saudi Arabia (KSA).
Methods
A representative sample of 565 school students aged 12–15 years was randomly selected from four schools in Jizan, KSA. The PA and EH were assessed using a validated self-administered questionnaire. A pre-post quasi-experimental study was implemented in three phases.
Results
Following the intervention, the school children in the intervention groups showed a significant improvement in their EH and PA. These improvements were documented in increased physical walking measured by the number of students walking daily, the number of days walked, and the time spent on vigorous activities (54.11 ± 54.89 to 63.24 ± 76.16). Fruits and vegetables had a similar consumption frequency in both the intervention and control groups. The snacks were frequently consumed among intervention group with a significant increase in the mean number from 1.64 ± 0.93 to 1.96 ± 1.13 (p = 0.000) and fast food were less frequently consumed among intervention group than the control group (p = 0.000). The prevalence of obesity in the intervention group was reduced from 16.3% to 12.9%, while it was significantly increased from 17.6% to 19.0% in the control group (p = 0.0148). Weight decreased by 0.37 kg in the intervention group, while it increased by 0.07 kg in the control group, but with no statistically significant increase.
Conclusion:
In conclusion, healthy lifestyle interventions can improve short- and long-term outcomes in school children. When examining the health benefits of healthy lifestyle, the importance of dietary and PA behaviors should be considered.
Keywords: lifestyle, dietary habits, physical activity, chronic diseases, Jazan-KSA
 
The association between leukocytes and sperm quality is concentration dependent
<p>Abstract</p> <p>Background</p> <p>To evaluate the association between leukocytes (polymorphonuclear granulocytes -PMNL) and semen parameters at different leukocyte concentrations.</p> <p>Methods</p> <p>This was a retrospective clinical study at a university hospital andrology clinic. Semen samples from infertile men were analyzed for sperm morphology and motility according to seminal leukocytes (PMNL) concentration (category A: >0 to <0.25 Ă— 10(6)/mL; category B: >0.25 to <0.5 Ă— 10(6)/mL; category C: >0.5 to <0.75 Ă— 10(6)/mL; category D: >0.75 to <1.0 Ă— 10(6)/mL, category E: >1 Ă— 10(6)/mL).</p> <p>Results</p> <p>The percentage of sperm with normal morphology increased significantly from category A (14%) to category D (19%) but decreased in category E to levels (14%) similar to those in category A. Motility grades a and a+b (combined) also increased from category A (12%, 20%) to category D (18.0%, 28.5%) and decreased in category E (11%, 20.5%) to levels similar to those in category A. Sperm deformities and motility grades c and d increased progressively in all categories.</p> <p>Summary</p> <p>Leukocytes had a positive association with normal morphology and progressive motility in semen samples at a concentration of 0-1 Ă— 10(6)/mL. The findings suggest that the association between leukocytes (PMNL) and semen quality might be concentration dependent.</p
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