Reproduction efficiency of the Horse Leech,Haemopis sanguisuga (Linnaeus, 1758)

The aquaculture sector has recently focused on alternative food sources due to increased costs and limited resources. Live food sources, such as invertebrates, have important roles in digestion processes of fish. It was aimed to determine the reproduction efficiency of the horse leech, Haemopis sanguisuga, which is expected to be used as an alternative live nutritional source in aquaculture in this study. The study was conducted at ambient temperature in the laboratory conditions for three months. A total of 25 gravid leeches with an average body mass of 6.91 ± 2.20 g were used. The leeches lost up to 75% of their body mass and laid 4.30 ± 1.49 cocoons at 12.0 ± 8.2 days interval during cocoon laying period. Leeches stopped laying cocoon when the temperature fell to 16 °C. The average of offspring hatched from the cocoons was 6.45 ± 2.86. The length–body mass relationship of the offspring was exponential (W = 0.012L^2.809, R² = 0.898). The results from the current study indicate that the basic biological parameter affecting the reproduction efficiency of H. sanguisuga is the size of the broodstock leeches, and reproduction activity weakens the broodstocks.     

Epibrassinolide prevents tau hyperphosphorylation via GSK3β inhibition in vitro and improves Caenorhabditis elegans lifespan and motor deficits in combination with roscovitine

Glycogen synthase kinase 3β (GSK3β) is considered an important element of glycogen metabolism; however, it has many other regulatory roles. Changes in the GSK3β signaling mechanism have been associated with various disorders, such as Alzheimer’s disease (AD), type II diabetes, and cancer. Although the effects of GSK3β inhibitors on reducing the pathological effects of AD have been described, an effective inhibitor has not yet been developed. Epibrassinolide (EBR), a brassinosteroid (BR), is structurally similar to mammalian steroid hormones. Our studies have shown that EBR has an inhibitory effect on GSK3β in different cell lines. Roscovitine (ROSC), a cyclin-dependent kinase (CDK) inhibitor, has also been identified as a potential GSK3 inhibitor. Within the scope of this study, we propose that EBR and/or ROSC might have mechanistic action in AD models. To test this hypothesis, we used in vitro models and Caenorhabditis elegans (C. elegans) AD strains. Finally, EBR treatment successfully protected cells from apoptosis and increased the inhibitory phosphorylation of GSK3β. In addition, EBR and/or ROSC treatment had a positive effect on the survival rates of C. elegans strains. More interestingly, the paralysis phenotype of the C. elegans AD model due to Aβ42 toxicity was prevented by EBR and/or ROSC. Our findings suggest that EBR and ROSC administration have neuroprotective effects on both in vitro and C. elegans models via inhibitory GSK3β phosphorylation at Ser9.

     

Mapping the folding free energy surface for metal-free human Cu,Zn superoxide dismutase

Mutations at many different sites in the gene encoding human Cu,Zn superoxide dismutase (SOD) are known to be causative agents in amyotrophic lateral sclerosis (ALS). One explanation for the molecular basis of this pathology is the aggregation of marginally soluble, partially structured states whose populations are enhanced in the protein variants. As a benchmark for testing this hypothesis, the equilibrium and kinetic properties of the reversible folding reaction of a metal-free variant of SOD were investigated. Reversibility was achieved by replacing the two non-essential cysteine residues with non-oxidizable analogs, C6A/C111S, to produce apo-AS-SOD. The metal-free pseudo-wild-type protein is folded and dimeric in the absence of chemical denaturants, and its equilibrium folding behavior is well described by an apparent two-state mechanism involving the unfolded monomer and the native dimer. The apparent free energy of folding in the absence of denaturant and at standard state is -20.37(+/- 1.04) kcal (mol dimer)(-1). A global analysis of circular dichroism kinetic traces for both unfolding and refolding reactions, combined with results from small angle X-ray scattering and time-resolved fluorescence anisotropy measurements, supports a sequential mechanism involving the unfolded monomer, a folded monomeric intermediate, and the native dimer. The rate-limiting monomer folding reaction is followed by a near diffusion-limited self-association reaction to form the native dimer. The relative population of the folded monomeric intermediate is predicted not to exceed 0.5% at micromolar concentrations of protein under equilibrium and both strongly unfolding and refolding conditions for metal-free pseudo-wild-type SOD.     

塔里木河下游胡杨林胸径结构及林木分布特征

采用“面”上宏观调查与“点”上典型研究相结合, 集中对塔里木河下游阿拉干断面100 hm2的胡杨(Populus euphratica)林木分布与胸径结构进行了调查。结果发现, 在距河道0-20 m的范围内, 胸径为0-4 cm的幼龄胡杨占最多, 达到13.24%。以后随着离河道距离的增加, 幼龄胡杨所占比例逐渐减小。胸径分布范围简单, 胸径为16-36 cm的林木株数在胡杨林中所占的比例最多。另外, 随着离河道距离的增加, 胸径在48 cm以上的过熟林和衰老林的比例逐渐增多。距河道0-200 m的范围内, 胡杨分布占整个胡杨林的80%以上。其中以疏失度为0-50%的长势较好的胡杨为主。在200-400 m的范围内, 疏失度为50%-75%的长势较差的过熟林和衰老林的比例开始增多。距河道400 m以上, 胡杨密度开始急剧下降, 胡杨株数所占的比例几乎下降到5%以下。     

Activity of the Human Rhinovirus 3C Protease Studied in Various Buffers,Additives and Detergents Solutions for Recombinant Protein Production

Proteases are widely used to remove affinity and solubility tags from recombinant proteins to avoid potential interference of these tags with the structure and function of the fusion partner. In recent years, great interest has been seen in use of the human rhinovirus 3C protease owing to its stringent sequence specificity and enhanced activity. Like other proteases, activity of the human rhinovirus 3C protease can be affected in part by the buffer components and additives that are generally employed for purification and stabilization of proteins, hence, necessitate their removal by tedious and time-consuming procedures before proteolysis can occur. To address this issue, we examined the effect of elution buffers used for common affinity based purifications, salt ions, stability/solubility and reducing agents, and detergents on the activity of the human rhinovirus 3C protease using three different fusion proteins at 4°C, a temperature of choice for purification of many proteins. The results show that the human rhinovirus 3C protease performs better at 4°C than the frequently used tobacco etch virus protease and its activity was insensitive to most of the experimental conditions tested. Though number of fusion proteins tested is limited, we expect that these finding will facilitate the use of the human rhinovirus 3C protease in recombinant protein production for pharmaceutical and biotechnological applications.     

Effect of vanadium on renal Na<Superscript>+</Superscript>,K<Superscript>+</Superscript>-ATPase activity in diabetic rats: a possible role of leptin

Several researches attempt to protect diabetic patients from the development of nephropathy. Involvement of leptin and renal Na⁺,K⁺-ATPase enzyme in diabetic nephropathy (DN) development is a recent field for researches. Vanadium, as a trace element with insulin mimetic effect, may act synergistically with insulin to protect against the development of DN. Sixty male Sprague Dawley rats were divided into six groups: control group (C), vanadium control group (CV), streptozotocin-induced diabetic group (D), insulin-treated diabetic group (DI), vanadium-treated diabetic group (DV), and combined insulin and vanadium-treated diabetic group. Six weeks later, systolic blood pressure (SBP) was measured and retro-orbital blood samples were collected to estimate glycosylated hemoglobin (HbA_1c), serum sodium (Na⁺) and creatinine, blood urea nitrogen (BUN) and plasma leptin levels. Preparation of microsomal fraction of renal tissue homogenate for estimation of Na⁺,K⁺-ATPase activity was done. The D group showed a significant increase in SBP, HbA_1c, serum Na⁺, creatinine, and BUN levels and Na⁺,K⁺-ATPase activity in microsomal fraction of renal tissue homogenate while plasma leptin level decreased significantly compared with C and CV groups. Both DI and DV groups showed a significant improvement in all the above measured parameters compared with D group while there were no significant changes between the DI and DV groups. Concomitant treatment with insulin and vanadium resulted in a significant improvement in all the measured parameters compared to each alone. Vanadium in combination with insulin ameliorates DN markers and reduces renal Na⁺,K⁺-ATPase overactivity in diabetic rats. An effect that may be partially mediated through correction of hypoleptinemia observed in these animals.     

An ANN model for treatment prediction in HBV patients

Two types of antiviral treatments, namely, interferon and nucleoside/nucleotide analogues are available for hepatitis infections. The selection of drug and dose determined using known pharmacokinetics and pharmacodynamics data is important. The lack of sufficient information for pharmacokinetics of a drug may not produce the desired results. Artificial neural network (ANN) provides a novel model-independent approach to pharmacokinetics and pharmacodynamics data. ANN model is created by supervised learning of 90 patients sample to predict the treatment strategy (lamivudine only and Lamivudine + Interferon) on the basis of viral load, liver function test, visit number, treatment duration, ethnic area, sex, and age. The model was trained with 68 (77.3%) samples and tested with 20 (22.7%) samples. The model produced 92% accuracy with 92.8% sensitivity and 83.3% specificity.     

Cryptosporidium parvum-induced ileo-caecal adenocarcinoma and Wnt signaling in a mouse model

Cryptosporidium species are apicomplexan protozoans that are found worldwide. These parasites constitute a large risk to human and animal health. They cause self-limited diarrhea in immunocompetent hosts and a life-threatening disease in immunocompromised hosts. Interestingly, Cryptosporidium parvum has been related to digestive carcinogenesis in humans. Consistent with a potential tumorigenic role of this parasite, in an original reproducible animal model of chronic cryptosporidiosis based on dexamethasone-treated or untreated adult SCID mice, we formerly reported that C. parvum (strains of animal and human origin) is able to induce digestive adenocarcinoma even in infections induced with very low inoculum. The aim of this study was to further characterize this animal model and to explore metabolic pathways potentially involved in the development of C. parvum-induced ileo-caecal oncogenesis. We searched for alterations in genes or proteins commonly involved in cell cycle, differentiation or cell migration, such as β-catenin, Apc, E-cadherin, Kras and p53. After infection of animals with C. parvum we demonstrated immunohistochemical abnormal localization of Wnt signaling pathway components and p53. Mutations in the selected loci of studied genes were not found after high-throughput sequencing. Furthermore, alterations in the ultrastructure of adherens junctions of the ileo-caecal neoplastic epithelia of C. parvum-infected mice were recorded using transmission electron microscopy. In conclusion, we found for the first time that the Wnt signaling pathway, and particularly the cytoskeleton network, seems to be pivotal for the development of the C. parvum-induced neoplastic process and cell migration of transformed cells. Furthermore, this model is a valuable tool in understanding the host-pathogen interactions associated with the intricate infection process of this parasite, which is able to modulate host cytoskeleton activities and several host-cell biological processes and remains a significant cause of infection worldwide.KEY WORDS: SCID mouse model, Cryptosporidiosis, Wnt pathway, Cytoskeleton, Digestive cancer     

Neuroprotective Effects of Lacosamide and Memantine on Hyperoxic Brain Injury in Rats

Neurochemical Research - In neonates supraphysiological oxygen therapy has been demonstrated to cause neuronal death in hippocampus, prefrontal cortex, parietal cortex, and retrosplenial cortex....     

Microbial transformation of phytosterols mixture from rice bran oil unsaponifiable matter by selected bacteria

Rice bran sample (12 Kg) was extracted and rice bran oil (RBO ≅ 76.8 g) was saponified. The resulted unsaponifiable matter of RBO (RBO unsap) was qualitatively and quantitatively estimated using different chromatographic analyses. RBO, produced 9.65% unsaponifiable matter with the following contents, cholesterol, 6.75%; stigmasterol, 3.4%; β. sitosterol, 10.23% and campesterol, 4.2%, in addition to unknown phytosterols, hydrocarbons and waxes. Microbial transformation process started by screening of 35 bacterial strains, locally isolated from rice bran, air and soil, using RBO unsap as a carbon and an energy source to produce some pharmaceutically useful C₁₈ and C₁₉ steroids. Moraxella ovis was the most potent isolate for its highest capability to utilize RBO unsap and selectively degrade the phytosterols side-chain producing androst-4-ene-3,17-dione (AD), androsta-1,4-diene-3,17-dione (ADD), testosterone (T) and estrone (E). The RBO unsap was the best carbon and energy source. Maximum production of the desired products was observed in 36 h, pH 7 and at 30°C by M. ovis.