[Effects of Vitrification with Self-made Carriers and Slow Programmed Freezing on Ovarian Tissue of Sheep].

Objective To investigate the effects of self-made carriers on the cryopreservation of ovarian tissue of sheep. Methods Thirty-two ovaries were randomly assigned to fresh group,programmed freezing group,self-made carrier I vitrification group,and self-made carrier Ⅱ vitrification group.The morphology,proliferation,apoptosis,and estrogen level of the ovarian tissue in each group were observed. Results After cryopreservation,the morphology normal rate of the primordial follicles in programmed freezing group,self-made carrier I vitrification group,and self-made carrier Ⅱ vitrification group were 74.2%,72.8%,and 72.3%,respectively,lower than that(83.7%)in the fresh group(χ2=13.079,P=0.004).The percentage of normal primary follicles in programmed freezing group was lower than that in the fresh group(χ2=12.486,P=0.000).The percentage of normal primary follicles showed no significant difference between vitrification groups and fresh group(P=1.000,P=0.972).There was no significant difference in estrogen level or the positive expression rate of PCNA among the 4 groups(F=0.363,P=0.780;χ2=0.359,P=0.949).The number of apoptotic cells in cryopreservation groups was significantly higher than that in the fresh group(F=37.584,P=0.000),and it was significantly higher in the programmed freezing group than in the two vitrification groups(F=18.992,P=0.000). Conclusion Compared with slow programmed freezing,the vitrification with self-made carriers could well preserve the activity of cells in large sheep ovarian tissue blocks.

The effect of emodin on cytotoxicity, apoptosis and antioxidant capacity in the hepatic cells of grass carp (Ctenopharyngodon idellus).

We determined the effect of emodin on the lactate dehydrogenase (LDH) release, superoxide dismutase (SOD), glutathione (GSH), total antioxidant capacity (T-AOC), reactive oxygen species (ROS), mitochondria membrane potential (ΔΨm), and apoptosis in the hepatic cells of grass carp (Ctenopharyngodon idellus). Cultured cells were treated with different concentrations of emodin (0.04-25 µg/ml) for 24 h. We found that the cytotoxic effect of emodin was mediated by apoptosis, and that this apoptosis occurred in a dose-dependent manner. Emodin (1-25 µg/ml) significantly induced apoptosis accompanying by ΔΨm disruption and ROS generation and significantly reduced the SOD activities and T-AOC compared to the control. Thus, the oxidative effect of emodin may be attributed to the loss of the cell's ability to maintain the activity of its radical-scavenging enzymes. GSH was also significantly higher after 0.2-1 µg/ml emodin exposure, indicating that cells failed to maintain their redox balance when compensating for the increased oxidative stress. Our results suggest that emodin (1-25 µg/ml) exerts its cytotoxic effects via apoptosis by directly affecting the mitochondria.

The influence of various feeding patterns of emodin on growth, non-specific immune responses, and disease resistance to Aeromonas hydrophila in juvenile Wuchang bream (Megalobrama amblycephala).

The present study was conducted to evaluate the effect of various feeding patterns of emodin on growth, non-specific immune response, and disease resistance to Aeromonas hydrophila in juvenile Wuchang bream. Healthy Megalobrama amblycephala (initial weight: 3.47 ± 0.032) were grown in a circulating water system for 8 weeks. Five groups were studied: one control group was fed with a basal diet for eight weeks (Pattern 1, P1), and three treatment groups were fed with a trial diet of 30 mg emodin kg(-1) at one-week (Pattern 2, P2), two-week (Pattern 3, P3), four-week (Pattern 4, P4) intervals. The final treatment group maintained the trial diet for the entire eight-week study duration (Pattern 5, P5). Results indicated that different feeding patterns of emodin significantly influenced the weight gain rate of Wuchang bream (P < 0.05). Fish in the P4 treatment group had significantly higher rates of weight gain (WG) than those in other treatment groups. There were no significant differences in survival rates or feed conversion ratios (FCR) between treatment groups and the control group. White blood cell count (WBC), respiratory burst activity, superoxide dismutase (SOD) activity, myeloperoxidase (MPO) activity and tumor necrosis factor-α (TNF-α) activity were shown to increase at first and then decrease from P3 condition to P5 condition. Fish under P4 treatment showed the most significant improvement of all tested parameters compared to control. Significantly higher levels (P < 0.05) of plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activity were observed in P2 and P4 treatment groups when compared with the control group, while no significant differences were observed in the AST and ALT activity of fish in P2, P3, P4 and P5 treatment groups. In a bacterial challenge experiment with A. hydrophila, fish under P4 and P5 treatment showed lower cumulative mortality than the control group. The results of this study suggest that an initial 4-week feeding interval is recommended for the economic and practical culture of M. amblycephala.

Searching for "environmentally-benign" antifouling biocides.

As the result of the ecological impacts from the use of tributyltins (TBT) in shipping, environmental legislation for the registration of chemicals for use in the environment has grown to a monumental challenge requiring product dossiers to include information on the environmental fate and behavior of any chemicals. Specifically, persistence, bioaccumulation and toxicity, collectively known as PBT, are properties of concern in the assessment of chemicals. However, existing measurements of PBT properties are a cumbersome and expensive process, and thus not applied in the early stages of the product discovery and development. Inexpensive methods for preliminary PBT screening would minimize risks arising with the subsequent registration of products. In this article, we evaluated the PBT properties of compounds reported to possess anti-fouling properties using QSAR (quantitative structure-activity relationship) prediction programs such as BIOWIN™ (a biodegradation probability program), KOWWIN™ (log octanol-water partition coefficient calculation program) and ECOSAR™ (Ecological Structure Activity Relationship Programme). The analyses identified some small (Mr < 400) synthetic and natural products as potential candidates for environmentally benign biocides. We aim to demonstrate that while these methods of estimation have limitations, when applied with discretion, they are powerful tools useful in the early stages of research for compound selection for further development as anti-foulants.

Toward Resolving the Resveratrol Conundrum: Synthesis and in Vivo Pharmacokinetic Evaluation of BCP-Resveratrol.

Over the last few decades, resveratrol has gained significance due to its impressive array of biological activities; however, its true potential as a drug has been severely constrained by its poor bioavailability. Indeed, several studies have implicated this bioavailability trait as a major road-block to resveratrol's potential clinical applications. To mitigate this pharmacokinetic issue, we envisioned a tactical bioisosteric modification of resveratrol to bicyclo[1.1.1]pentane (BCP) resveratrol. Relying on the beneficial bioisosteric potential demonstrated by the BCP-scaffold, we hypothesized that BCP-resveratrol would have an inherently better in vivo PK profile as compared to its natural counterpart. To validate such a hypothesis, it was necessary to secure a synthetic access to this novel structure. Herein we describe the first synthesis of BCP-resveratrol and disclose its PK properties.