249 research outputs found
Energetic Cost and Physiological Trade-offs
Understanding how organisms allocate limited resources across physiological systems is a major challenge in biology. This study revealed that high energetic demand of electric signals of male electric fish (Brachyhypopomus gauderio) is matched by a metabolic trade-off with other cellular functions. We used thyroxine (T4) to modulate the fishâs signal metabolism, partitioned the energy budget pharmacologically, and measured energy consumption using oxygen respirometry. In males, total energy consumption was unchanged pre- and post-T4 treatment, while signal metabolism rose and the standard metabolic rate fell in an even trade-off. Total metabolism in females did the opposite. Under T4, the non-signal resting metabolism rose while the signal metabolismfell. These results reveal sex differences in metabolic trade-offs between signaling and cellular metabolism in electric fish and suggest that thyroid hormones regulate the allocation of energy between electric signals and somatic maintenance in favor of reproduction.
To determine whether electric fish trade-off reproduction against innate immunity, as is common in vertebrates, we assessed changes in the bactericidal activity of plasma in B. gauderio challenged with bacterial lipopolysaccharide (LPS), before and after T4 treatment. Females did not modulate innate immunity with any of the treatments, while males elevated bactericidal activity of plasma by about a third following LPS injections, T4 implants, or both together, relative to sham treatment. This outcome was unexpected given that T4 increases the energy consumed by the maleâs reproductive electric signals while lowering the rest of his metabolism. T4 also increased expression of Na+K+ATPase pump mRNA in the electrogenic cells of males but not females, consistent with previous findings that T4 differentially regulates signal metabolism in the two sexes. This sex difference in gene regulation suggests Na+K+ATPase underlies sexual dimorphism in electric signal energetics. The results provide further evidence that thyroid hormones play an essential role in the differential allocation of energy among metabolic functions.
This body of work is the first to quantify an energetic trade-off between reproductive behavior and other metabolic functions. and implicates ion pumps, but not innate immunity, as molecular mechanisms underlying sex differences found in these energetic trade-offs
Multifocus Images Fusion Based On Homogenity and Edges Measures
Image fusion is one of the most important techniques in digital image processing, includes the development of software to make the integration of multiple sets of data for the same location; It is one of the new fields adopted in solve the problems of the digital image, and produce high-quality images contains on more information for the purposes of interpretation, classification, segmentation and compression, etc. In this research, there is a solution of problems faced by different digital images such as multi focus images through a simulation process using the camera to the work of the fuse of various digital images based on previously adopted fusion techniques such as arithmetic techniques (BT, CNT and MLT), statistical techniques (LMM, RVS and WT) and spatial techniques (HPFA, HFA and HFM). As these techniques have been developed and build programs using the language MATLAB (b 2010). In this work homogeneity criteria have been suggested for evaluation fused digital image's quality, especially fine details. This criterion is correlation criteria to guess homogeneity in different regions within the image by taking a number of blocks of different regions in the image and different sizes and work shifted blocks per pixel. As dependence was on traditional statistical criteria such as (mean, standard deviation, and signal to noise ratio, mutual information and spatial frequency) and compared with the suggested criteria to the work. The results showed that the evaluation process was effective and well because it took into measure the quality of the homogenous regions
Formulation and in-vitro evaluation of fast dissolving tablets containing a poorly soluble antipsychotic drug
The aim of the present study was to formulate olanzapine fast dissolving tablets (FDT). Olanzapine is a poorly water soluble drug that undergoes first pass metabolism in liver resulted in low oral bioavailability. The water solubility is enhanced by formation of co-amorphous dispersion by solvent evaporation under vacuum method using a polycarboxylic acid (ascorbic acid) as a coformer in two different molar ratios (1:1 and 1:2). The prepared systems were evaluated using differential scanning calorimeter (DSC), Fourier Transform Infra-Red analysis (FTIR), X-ray powder diffraction (XRPD), Scanning electron microscopy (SEM) and saturated solubility. The co-amorphous dispersion system in a molar ratio 1:2 is higher in solubility than 1:1, so it was selected for incorporation into FDT formulation. Compatability study between olanzapine and different tablet excipients including DSC and FTIR showed that the drug is compatible with the selected tablet excipients. Direct compression method was used in FDT formulations using different types and concentrations of superdisintegrants. FDTs were evaluated for weight variation, hardness, friability, wetting time, drug content uniformity, invitro disintegration time and invitro dissolution study. All the prepared FDTs were complied with the compendia standards. F3 and F8 showed lower disintegration time and higher percent of drug dissolved, so they were selected for stability study. After storage for 3 months at 30ÂșC at 65% relative humidity, both formulations were physically stable regarding color and integrity and had only minor increases in disintegration time, drug content and friability after three monthsâ storage. The results indicate that olanzapine FDT tablets may serve as a successful strategy for enhancing the bioavailability of olanzapine
Treatment results and prognostic factors of pediatric neuroblastoma: a retrospective study
<p>Abstract</p> <p>Background</p> <p>We conducted a retrospective analysis to investigate treatment results and prognostic factors of pediatric neuroblastoma patients.</p> <p>Methods</p> <p>This retrospective study was carried out analyzing the medical records of patients with the pathological diagnosis of neuroblastoma seen at South Egypt Cancer Institute, Assiut University during the period from January 2001 and January 2010. After induction chemotherapy, response according to international neuoblastoma response criteria was assessed. Radiotherapy to patients with residual primary tumor was applied. Overall and event free survival (OAS and EFS) rates were estimated using Graphed prism program. The Log-rank test was used to examine differences in OAS and EFS rates. Cox-regression multivariate analysis was done to determine the independent prognostic factors affecting survival rates.</p> <p>Results</p> <p>Fifty three cases were analyzed. The median follow-up duration was 32 months and ranged from 2 to 84 months. The 3-year OAS and EFS rates were 39.4% and 29.3% respectively. Poor prognostic factors included age >1 year of age, N-MYC amplification, and high risk group. The majority of patients (68%) presented in high risk group, where treatment outcome was poor, as only 21% of patients survived for 3 year.</p> <p>Conclusion</p> <p>Multivariate analysis confirmed only the association between survival and risk group. However, in univariate analysis, local radiation therapy resulted in significant survival improvement. Therefore, radiotherapy should be given to patients with residual tumor evident after induction chemotherapy and surgery. Future attempts to improve OAS in high risk group patients with aggressive chemotherapy and bone marrow transplantation should be considered.</p
Antioxidant, antimicrobial, and theoretical studies of the thiosemicarbazone derivative Schiff base 2-(2-imino-1-methylimidazolidin-4-ylidene)hydrazinecarbothioamide (IMHC)
Insulin sensitizing agent improves clinical pregnancy rate and insulin resistant parameters in polycystic ovarian syndrome patients with acanthosis nigricans: a randomized controlled study
Objective: To investigate the effect of adding metformin to clomiphene citrate (CC) in polycystic ovarian syndrome (PCOS) patients with acanthosis nigricans (AN) who were previously not responding to CC.
Material and Methods: A double blinded randomized controlled trial (NCT02562664) included 66 PCOS women with acanthosis nigricans who were CC resistant (at least 3 months). Day 3 follicle stimulating hormone (FSH) level, fasting insulin, fasting glucose and homeostatic model assessment were used to quantify insulin resistance. Participants were randomly assigned to either group I (CC with placebo tablets) or group II (CC with metformin) for three cycles. Insulin resistance parameters as well as clinical pregnancy rate had been evaluated in both groups. The statistical analysis was done using Chi- square and Fischer exact tests.
Results: The demographic data was comparable in both groups, however; there was higher cumulative pregnancy rate after three cycles of stimulation in group II (18/33) (54.5%) in comparison with group I (7/33) (21.1%) (P=0.03). There was a significant improvement in the insulin resistance parameters after three months of combining clomiphene citrate with metformin as compared with CC alone.
Conclusion: Adding metformin to CC in clomiphene citrate resistant PCOS patients who have acanthosis nigricans improves the pregnancy rate and insulin resistant parameters
The role of hepatic progenitor cells in predicting response to therapy in Egyptian patients with chronic hepatitis C, genotype 4
Background: Interferon therapy is used as a line of treatment of chronic hepatitis C virus (HCV) in several areas of the world including Egypt.Objective: Our aim was to investigate the value of hepatic progenitor cells (HPCs) in predicting response of patients with chronic HCV, genotype 4 to pegylated interferon (PEGIFN) plus ribavirin (RBV) therapy.Methods: Pre-treatment liver biopsies obtained from 110 patients with chronic HCV, genotype 4 were examined immunohisto- chemically for HPCs using cytokeratin19. The mean number of HPCs as ductular reaction (DR) and as isolated progenitor cells (IPCs) was counted in each case. The patients were classified into: those with sustained virological response (SVR) and those who did not achieve SVR. The results were compared between the two groups. Also, the relationships between HPCs and other clinico-pathologic variables were estimated using multivariate analysis.Results: The mean number of HPCs was the only independent predictor of therapeutic response, being significantly higher in non-responders (P = 0 for DR and P = 0.03 for IPCs). On the other hand, fibrosis stage and steatosis were the only independent factors which showed a significant direct association with the mean number of HPCs in the form of DR and IPCs (P = 0 for each).Conclusion: The number of HPCs provides prognostic information in chronic HCV since it is significantly associated with stage of fibrosis. More importantly, it can be used as a marker to predict response of patients with chronic HCV to PEGIFN plus RBV therapy.Keywords: Chronic hepatitis C, genotype 4, response to therapy, hepatic progenitor cells
Potential of Aloe vera and Amaryl in amelioration of hyperglycemia correlated with Streptozotocin induced diabetes
Diabetes mellitus (DM) is multifarious group of disorders distinguished with hyperglycemia. Streptozotocin (STZ) induced diabetes frequently occurs animal model in the medical researches. Hence, amelioration of hyperglycemia associated with diabetes is a cardinal target for therapeutics. Therefore, this work aimed to assesses the possible ameliorative characteristic of Aloe vera and Amaryl in STZ-induced diabetes. In this study, forty male Wistar rats within average weight 130±20 gm and age 6-7 weeks were used. The animals were evenly divided; 10 rats of each as follow. Group 1 served as control. Group 2 only received STZ. Group 3 received STZ + Aloe vera extract. Group 4 received STZ + Amaryl. Venous blood samples collected for biochemical assay using colorimetric methods. Besides this, specimens from pancreas were excised for the histological findings. Biochemically, STZ induced diabetic rats led to significant elevation in mean levels of blood glucose, total bilirubin and malondialdehyde (MDA) when compared with control. Contrary, activity of superoxide dismutase (SOD) was significantly decreased in STZ induced group in comparison with control. In contrast, the administrations of Aloe vera and amaryl to STZ diabetic rats showed an improvement in the mean values of the altered parameters. Histopathology, diabetic group revealed vacuolation of the pancreatic B-cells, besides inflammatory edema. Aloe vera and amaryl treated groups exhibited apparently normal pancreatic tissues. Depending on theses evidence, we could say that Aloe vera followed by amaryl could have contributed for an improvement of the pathophysiological alterations promoted by STZ induced diabetes
Bilosomes as a promising nanoplatform for oral delivery of an alkaloid nutraceutical:improved pharmacokinetic profile and snowballed hypoglycemic effect in diabetic rats
Diabetes mellitus is a life-threatening metabolic disease. At the moment, there is no effective treatment available to combat it. In this study, we aimed to develop berberine-loaded bilosomes (BER-BLS) to boost the oral bioavailability and therapeutic efficacy of berberine, a natural antidiabetic medication. The BER-BLS was fabricated using a thin-film hydration strategy and optimized using a central composite design (face-centered). The average vesicle size, entrapment efficiency, and surface charge of the optimized BER-BLS preparation were 196.5ânm, 89.7%, (â) 36.4âmV, respectively. In addition, it exhibited higher stability and better-sustained release of berberine than the berberine solution (BER-SOL). BER-BLS and BER-SOL were administered to streptozocin-induced diabetic rats. The optimized BER-BLS formulation had a significant hypoglycemic impact, with a maximum blood glucose decrease of 41%, whereas BER-SOL only reduced blood glucose by 19%. Furthermore, the pharmacological effect of oral BER-BLS and BER-SOL corresponded to 99.3% and 31.7%, respectively, when compared to subcutaneous insulin (1âIU). A pharmacokinetic analysis found a 6.4-fold rise in the relative bioavailability of berberine in BER-BLS when compared to BER-SOL at a dosage of 100âmg/kg body weight. Histopathological investigation revealed that BER-BLS is suitable for oral administration. Our data demonstrate that BLS is a potential nanocarrier for berberine administration, enhancing its oral bioavailability and antidiabetic activity
Assessment of Photodynamic Therapy and Nanoparticles Effects on Caries Models
AIM: To assess the antibacterial competence of 650 nm diode laser, Methylene Blue (MB) and Silver Nano-Particles (Ag NPs) on Streptococcus mutans in biofilm-induced caries models.MATERIAL AND METHODS: One hundred eighty specimens were prepared and equally divided into 6 groups. One group was untreated (control), and the others were subjected to either MB, laser, Ag NPs, the combination of MB and Laser or MB, laser and Ag NPs.RESULTS: Comparison of the log10 mean Colony Forming Units per millilitre (CFU/ml) values of each of the treated 5 groups and the control group was found statistically significant (P-value < 0.05).The combination of MB, laser and Ag NPs recorded the greatest reduction (95.28%). MB alone represented the least capable (74.09%). The efficiency differences among the Ag NPs treated group; the Laser treated group and the combined MB/Laser treated group were found statistically insignificant.CONCLUSION: The combination of MB, 650 nm diode laser and Ag NPs may be among the highly effective modern antimicrobial therapeutics in dentistry
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