Combined use of dbcAMP and IBMX minimizes the damage induced by a long‐term artificial meiotic arrest in mouse germinal vesicle oocytes

Phosphodiesterase (PDE)‐mediated reduction of cyclic adenosine monophosphate (cAMP) activity can initiate germinal vesicle (GV) breakdown in mammalian oocytes. It is crucial to maintain oocytes at the GV stage for a long period to analyze meiotic resumption in vitro. Meiotic resumption can be reversibly inhibited in isolated oocytes by cAMP modulator forskolin, cAMP analog dibutyryl cAMP (dbcAMP), or PDE inhibitors, milrinone (Mil), Cilostazol (CLZ), and 3‐isobutyl‐1‐methylxanthine (IBMX). However, these chemicals negatively affect oocyte development and maturation when used independently. Here, we used ICR mice to develop a model that could maintain GV‐stage arrest with minimal toxic effects on subsequent oocyte and embryonic development. We identified optimal concentrations of forskolin, dbcAMP, Mil, CLZ, IBMX, and their combinations for inhibiting oocyte meiotic resumption. Adverse effects were assessed according to subsequent development potential, including meiotic resumption after washout, first polar body extrusion, early apoptosis, double‐strand DNA breaks, mitochondrial distribution, adenosine triphosphate levels, and embryonic development. Incubation with a combination of 50.0 μM dbcAMP and 10.0 μM IBMX efficiently inhibited meiotic resumption in GV‐stage oocytes, with low toxicity on subsequent oocyte maturation and embryonic development. This work proposes a novel method with reduced toxicity to effectively arrest and maintain mouse oocytes at the GV stage.     

Melatonin Alleviates Drought-Induced Damage of Photosynthetic Apparatus in Maize Seedlings

Russian Journal of Plant Physiology - Melatonin plays an important role in the enhancement of plant tolerance to drought stress. The underlying mechanisms of this melatonin-induced protection of...     

Aidi injection,a traditional Chinese biomedical preparation for gynecologic tumors: a systematic review and PRISMA-compliant meta-analysis

Aidi injection (ADI), a traditional Chinese biomedical preparation, is a promising adjuvant therapy for gynecologic tumors (GTs), including cervical cancer (CC), endometrial cancer (EC), and ovarian cancer (OC). Although studies have reported positively on ADI therapy, its exact effects and safety in GT patients remain controversial. Therefore, a wide-ranging systematic search of electronic databases was performed for this meta-analysis. Data from 38 trials including 3309 GT patients were analyzed. The results indicated that the combination of conventional treatment and ADI markedly improved the patients’ overall response rate (P<0.00001), disease control rate (P<0.00001), and quality of life (P<0.05) compared with conventional treatment alone. Furthermore, patient immunity was enhanced with combined treatment, as indicated by significantly increased percentages of CD3⁺ (P=0.005) and CD4⁺ (P<0.00001) and increased CD4⁺/CD8⁺ ratio (P=0.001). Most of the adverse events caused by radiochemotherapy such as gastrointestinal issues, leukopenia, thrombocytopenia, and hepatotoxicity, (P<0.05 for all) were significantly alleviated when ADI was used in the GT patients. However, other adverse events such as nephrotoxicity, diarrhea, alopecia, and neurotoxicity did not significantly differ between the two groups. Overall, these results suggest that the combination of conventional and ADI treatment is more effective than conventional treatment alone.     

Length-weight relationships of eight fish species from the Hailang river,China

The present study reports the length-weight relationships (LWRs) for eight fish species sampled in Hailang River, a left-bank tributary of the Mudan River in Northeast China. The fishes were collected from April to October bimonthly 2017 by electrofishing (fishing 2 kilometers along the river and within 5 meters from the bank) and netting (drift gillnet: mesh size 2 cm × 3 cm; 200 m net length). The specimens were weighed (nearest 0.1 g) and measured (nearest 0.1 cm) in the laboratory. This study provides an update in maximum lengths for five species.     

Isoflurane promotes proliferation of squamous cervical cancer cells through mTOR-histone deacetylase 6 pathway

Molecular and Cellular Biochemistry - This study investigated the effect of isoflurane on the proliferation of squamous cervical cancer cells, with focus on histone deacetylase 6 that is closely...     

The TFIID pivot of preinitiation complex

Science China Life Sciences -     

Molecular probes for the human adenosine receptors

Adenosine receptors, G protein–coupled receptors (GPCRs) that are activated by the endogenous ligand adenosine, have been considered potential therapeutic targets in several disorders. To date however, only very few adenosine receptor modulators have made it to the market. Increased understanding of these receptors is required to improve the success rate of adenosine receptor drug discovery. To improve our understanding of receptor structure and function, over the past decades, a diverse array of molecular probes has been developed and applied. These probes, including radioactive or fluorescent moieties, have proven invaluable in GPCR research in general. Specifically for adenosine receptors, the development and application of covalent or reversible probes, whether radiolabeled or fluorescent, have been instrumental in the discovery of new chemical entities, the characterization and interrogation of adenosine receptor subtypes, and the study of adenosine receptor behavior in physiological and pathophysiological conditions. This review summarizes these applications, and also serves as an invitation to walk another mile to further improve probe characteristics and develop additional tags that allow the investigation of adenosine receptors and other GPCRs in even finer detail.

     

Integration of geometric separation mechanisms by implementing curved constrictions in a biochip microchannel fluidic separator

This paper investigates the effectiveness of using curved constrictions in the bifurcation region of T-type fluid separators for promoting flow development in the intervals between bifurcations. A design of biofluid separator is proposed and a mathematical analysis and a numerical simulation of the blood flow in microchannels are conducted. The design is based on a modification of an existing T-shaped biochip device which consists of a main channel and a series of perpendicularly positioned side channels. By means of bifurcation effect, the blood is separated into plasma concentration flow from the side channels and blood cell concentration flow from the main channel. In this design, curved constrictions are inserted between bifurcations to replace the original straight channel section, so that the constriction and curved channel effects can be induced apart from the existing bifurcation effect. The mathematical analysis is aimed to the flow field and shear stress of the blood fluid in the microchannel geometries employed in the current design, including bifurcation, constriction and curved channel. The numerical simulation and mathematical analysis result in agreed conclusions, giving some insights into the importance of the relevant geometries in promoting biofluid separation. The main results can be summarised as follows: (i) the constrictions can largely increase the shear stress by the ratio of square of the reduction of the sections between the constriction and parent main channel. (ii) The curved channel intervals can induce centrifugal force, smoothly transit the flow field and increase the chances depleting fluid from the cell-free layer. (iii) The thickness of the boundary layer skimmed into the side channels from the main channel is decreased in this design and can be controlled, falling into the cell-free layer region by adjusting the geometry of the side channels.