The effects of gradual or abrupt changes in salinity on digestive enzymes activity of Caspian kutum,Rutilus kutum (Kamensky, 1901) larvae

This study investigates the effects of gradual or abrupt changes in rearing salinity on food transit time and digestive enzymes activity of Caspian kutum (Rutilus kutum) larvae. The larvae (532 ± 0.05 mg) were supplied and randomly allocated into 12 tanks at a density of 45 fish per tank. Experimental treatments were fresh water (salinity 0) [FW] as control, exposure to salinity 5 [T₁], and gradual transfer to salinity 10 in two steps of first to 5 h, then and after 12 h to a salinity of 10 [T₂], and abrupt change (direct transfer to a salinity of 10 [T₃]). Results showed at 8 h after start of feeding that the larvae intestine was filled with food pellets except in treatment T₁. Enzyme activity responded to salinity change as follows: the highest trypsin, amylase, and chymotrypsin activities were observed in T₁; however, these were not significantly different to treatment T₃ (P > 0.05). Trypsin activity peaks in the FW and T₂ groups occurred 8 h after feeding, and in T₃ and T₁ groups 5 h after feeding. Peak chymotrypsin and alkaline phosphatase activity was observed 5 and 8 h after feeding in all experiments, respectively. The highest α amylase activity in FW and T₂ groups occurred 5 h after feeding, while in T₃ and T₁ these peaks were observed 8 h after feeding. These results indicate that salinity had some noticeable effects on the activities of digestive enzymes after feeding.     

Compensatory growth in juvenile roach Rutilus caspicus: effect of starvation and re‐feeding on growth and digestive surface area

The aim of this study was to investigate compensatory growth in juvenile Rutilus caspicus during starvation and re‐feeding periods. The results confirmed the existence of compensatory growth in R. caspicus which depended on the duration of food deprivation. Complete compensatory growth occurred in the fish that were food deprived for at least 3 weeks. Starvation and re‐feeding had no significant effect on the digestive somatic index and intestinal surface areas in the fish that were food deprived for 1 week, while they showed a significant decrease and increase, during starvation and re‐feeding in the fish that were food deprived for 2 and 3 weeks. This knowledge may have application in aquaculture, as appropriate exploitation of compensatory growth can give increased growth rate and feeding efficiency.     

Impact of prolonged oocyte incubation time before vitrification on oocyte survival,embryo formation,and embryo quality in mice

Oocyte incubation time before freezing is one of the factors affecting oocyte vitrification. In the assisted reproductive technology (ART) clinics, it is sometimes decided to perform oocyte vitrification after a long period of incubation time due to various conditions, such as inability to collect semen samples, unsuccessful urological interventions (PESA, TESE, etc.), or unexpected conditions. A time factor of up to 6 h has been studied in the available reports. Therefore, this study was designed to evaluate oocyte incubation time before freezing at 0, 6, 12, 18, and 24 h after retrieval. Metaphase II (MII) oocytes were obtained from NMRI female mice after being randomly divided into the five groups of 0, 6, 12, 18, and 24 h of freezing via hormonal stimulation following retrieval and entered into the vitrification-warming process. The thawed oocytes were evaluated according to the survival criteria and then inseminated with the sperms of male mice for in vitro fertilization. The next day, the embryo formation rate and embryo quality were assessed. Our results demonstrated that even after 24 h of incubation, the survival rate of oocytes was 51.35% with the embryo formation rate of 73.21%. However, the survival and embryo formation rates significantly decreased within 12, 18, and 24 h after retrieval compared to the groups vitrified at 0 h. The embryo quality was significantly reduced by vitrification at 0 to 24 h after retrieval. According to our data, although a prolonged incubation time before freezing reduced the survival rate, there was still a chance for oocytes to stay alive with acceptable embryo formation and quality rates after vitrification warming of oocytes.     

Comparison of PRIMO Monte Carlo code and Eclipse treatment planning system in calculation of dosimetric parameters in brain cancer radiotherapy

BackgroundIt is important to evaluate the dose calculated by treatment planning systems (TPSs) and dose distribution in tumor and organs at risk (OARs). The aim of this study is to compare dose calculated by the PRIMO Monte Carlo code and Eclipse TPS in radiotherapy of brain cancer patients.Materials and methodsPRIMO simulation code was used to simulate a Varian Clinac 600C linac. The simulations were validated for the linac by comparison of the simulation and measured results. In the case of brain cancer patients, the dosimetric parameters obtained by the PRIMO code were compared with those calculated by Eclipse TPS. Gamma function analysis with 3%, 3 mm criteria was utilized to compare the dose distributions. The evaluations were based on the dosimetric parameters for the planning target volume (PTV) and OAR including D_min, D_mean, and D_max, homogeneity index (HI), and conformity index (CI).ResultsThe gamma function analysis showed a 98% agreement between the results obtained by the PRIMO code and measurement for the percent depth dose (PDD) and dose profiles. The corresponding value in comparing the dosimetric parameters from PRIMO code and Eclipse TPS for the brain patients was 94%, on average. The results of the PRIMO simulation were in good agreement with the measured data and Eclipse TPS calculations.ConclusionsBased on the results of this study, the PRIMO code can be utilized to simulate a medical linac with good accuracy and to evaluate the accuracy of treatment plans for patients with brain cancer.     

Myeloid deletion and therapeutic activation of AMPK do not alter atherosclerosis in male or female mice

The dysregulation of myeloid-derived cell metabolism can drive atherosclerosis. AMP-activated protein kinase (AMPK) controls various aspects of macrophage dynamics and lipid homeostasis, which are important during atherogenesis. Using LysM-Cre to drive the deletion of both the α1 and α2 catalytic subunits (MacKO), we aimed to clarify the role of myeloid-specific AMPK signaling in male and female mice made acutely atherosclerotic by injection of AAV vector encoding a gain-of-function mutant PCSK9 (PCSK9-AAV) and WD feeding. After 6 weeks of WD feeding, mice received a daily injection of either the AMPK activator A-769662 or a vehicle control for an additional 6 weeks. Following this (12 weeks total), we assessed myeloid cell populations and differences between genotype or sex were not observed. Similarly, aortic sinus plaque size, lipid staining, and necrotic area did not differ in male and female MacKO mice compared with their littermate floxed controls. Moreover, therapeutic intervention with A-769662 showed no treatment effect. There were also no observable differences in the amount of circulating total cholesterol or triglyceride, and only minor differences in the levels of inflammatory cytokines between groups. Finally, CD68+ area and markers of autophagy showed no effect of either lacking AMPK signaling or AMPK activation. Our data suggest that while defined roles for each catalytic AMPK subunit have been identified, complete deletion of myeloid AMPK signaling does not significantly impact atherosclerosis. Additionally, these findings suggest that intervention with the first-generation AMPK activator A-769662 is not able to stem the progression of atherosclerosis.     

Cks85A and Skp2 interact to maintain diploidy and promote growth in Drosophila

The Cks or Suc1 proteins are highly conserved small proteins that play remarkably diverse roles in the cell cycle. All Cks homologues have the ability to associate with Cyclin dependent kinases (Cdks) and in many cases this interaction has been shown to be important for function. Here we characterize the null and RNAi knockdown phenotype of the Drosophila Cks1 (Cks85A) gene. Cks85A is essential for viability in Drosophila. Cks85A null animals have reduced overall growth and this correlates with reduced ploidy and impaired DNA replication in endoreplicating cells. Interestingly, Cks85A is also required for the maintenance of diploidy in mitotically cycling cells. The requirement for Cks85A in growth is similar to that of the mammalian Cks1, which was found to interact with the SCF^Skp2 ubiquitin ligase. We identified the Drosophila Skp2 gene and generated null alleles. Comparison of these mutants to null mutants for Cks85A reveals a remarkably similar dual requirement in growth and in maintenance of diploidy. We find that Cks85A interacts directly with the SCF^Skp2 ubiquitin ligase and genetic evidence indicates that this is its major molecular function. The closely related Cks30A cannot interact with the SCF^Skp2 and cannot functionally compensate for loss of Cks85A. We also find that the critical growth promoting and diploidy maintaining functions of Cks85A and Skp2 are independent of known SCF^Skp2 substrates, p27 and Cdt1, indicating that other critical substrates remain to be identified.