The subsequent biological effects of simulated microgravity on endothelial cell growth in HUVECs.

PURPOSE: Microgravity is known to cause endothelium dysfunction in astronauts returning from spaceflight. We aimed to reveal the regulatory mechanism in alterations of human endothelial cells after simulated microgravity (SMG). METHODS: We utilized the rotary cell culture system (RCCS-1) to explore the subsequent effects of SMG on human umbilical vein endothelial cells (HUVECs). RESULTS: SMG-treated HUVECs appeared obvious growth inhibition after return to normal gravity, which might be attributed to a set of responses including alteration of cytoskeleton, decreased cell adhesion capacity and increased apoptosis. Expression levels of mTOR and its downstream Apaf-1 were increased during subsequent culturing after SMG. miR-22 was up-regulated and its target genes SRF and LAMC1 were down-regulated at mRNA levels. LAMC1 siRNAs reduced cell adhesion rate and inhibited stress fiber formation while SRF siRNAs caused apoptosis. CONCLUSION: SMG has the subsequent biological effects on HUVECs, resulting in growth inhibition through mTOR signaling and miR-22-mediated mechanism.

Protective effects of melatonin on bovine sperm characteristics and subsequent in vitro embryo development.

We aimed to investigate the effect of melatonin on bovine frozen-thawed semen and its impact on fertilization outcome. Plasma membrane integrity, mitochondrial activity, acrosome integrity, and levels of intracellular reactive oxygen species (ROS) were measured in spermatozoa treated with different concentrations of melatonin. Melatonin-treated spermatozoa were then used for in vitro fertilization, followed by analysis of subsequent embryo development and the expression of apoptosis- and antioxidant-related genes. The results revealed that 10-5 and 10-3 M melatonin led to higher plasma membrane integrity, mitochondrial activity, and acrosome integrity, and significantly decreased intracellular ROS levels (P < 0.05). The blastocyst development rate of in vitro-produced bovine embryos originating from 10-3 M melatonin-treated spermatozoa was significantly higher, while the incidence of apoptotic nuclei in blastocysts was markedly lower than for embryos from any other group (P < 0.05). CASP3 and BAX mRNA abundance were significantly reduced whereas BCL2, XIAP, and CAT transcript abundance were significantly increased in embryos produced from spermatozoa treated with 10-3 M melatonin; GPX4 expression, however, was comparable in all treatment groups. Thus, 10-3 M melatonin can improve the quality of bovine frozen-thawed semen. These beneficial effects appear to influence preimplantation embryos, given the correlation with its anti-apoptotic and anti-oxidative properties. Mol. Reprod. Dev. 83: 993-1002, 2016 © 2016 Wiley Periodicals, Inc.

Melatonin inhibits paraquat-induced cell death in bovine preimplantation embryos.

Preimplantation embryos are sensitive to oxidative stress-induced damage that can be caused by reactive oxygen species (ROS) originating from normal embryonic metabolism and/or the external surroundings. Paraquat (PQ), a commonly used pesticide and potent ROS generator, can induce embryotoxicity. The present study aimed to investigate the effects of melatonin on PQ-induced damage during embryonic development in bovine preimplantation embryos. PQ treatment significantly reduced the ability of bovine embryos to develop to the blastocyst stage, and the addition of melatonin markedly reversed the developmental failure caused by PQ (20.9% versus 14.3%). Apoptotic assay showed that melatonin pretreatment did not change the total cell number in blastocysts, but the incidence of apoptotic nuclei and the release of cytochrome c were significantly decreased. Using real-time quantitative polymerase chain reaction analysis, we found that melatonin pre-incubation significantly altered the expression levels of genes associated with redox signaling, particularly by attenuating the transcript level of Txnip and reinforcing the expression of Trx. Furthermore, melatonin pretreatment significantly reduced the expression of the pro-apoptotic caspase-3 and Bax, while the expression of the anti-apoptotic Bcl-2 and XIAP was unaffected. Western blot analysis showed that melatonin protected bovine embryos from PQ-induced damage in a p38-dependent manner, but extracellular signal-regulated kinase (ERK) and c-JUN N-terminal kinase (JNK) did not appear to be involved. Together, these results identify an underlying mechanism by which melatonin enhances the developmental potential of bovine preimplantation embryos under oxidative stress conditions.

Diversity and stability study on rice mutants induced in space environment.

To further study the characteristics of changes on the molecular level of rice mutants induced in space environment, we analyzed proteins in leaves and seeds of four rice mutants (two high-tillering and two low-tillering) in the 8(th) and 9(th) generations after a 15-day spaceflight, and compared with their ground controls by two-dimentional polyacrylamide gel electrophoresis and reverse phase liquid chromatography (RPLC). In addition, the albumin, globulin, prolamine, glutelin, and amylose of the mutant seeds were analyzed by RPLC and ultra-violet spectrometry. The results showed that the low-abundance proteins of leaves in the peak tillering stage are more likely to be induced compared with their corresponding controls. The albumin, globulin, and prolamine of the mutant seeds revealed changes when compared with their controls, and the characteristics of changes in different mutants were stably inherited in the 8(th) and 9(th) generations, suggesting that they can be used as bio markers to identity the mutants induced by spaceflight. Moreover, two proteins (SSP9111 and SSP6302) were found to be expressed with high intensity (two-fold change) in different mutants, which were both correlated with photosystem according to mass spectrometry and database searching.

[Navigated percutaneous placement of iliosacral screws using intra-operative three-dimensional imaging].

OBJECTIVE: To investigate the effect of a new technique of navigated percutaneous placement of iliosacral screws using intra-operative three-dimensional (3D) imaging. METHODS: Sixteen patients with hip fracture were placed in supine position. After the reference marker was fixed on the iliac crest, a 3-D C-arm navigation system was used intra-operatively to obtain 3D images that were transferred to the navigation system by an automatic. Registration process to calculate the length of screw and direction to insert it. A navigated pointer defined the entry point, while navigated percutaneous drilling was done accordingly with a navigated drill bit in combination with a navigated drill sleeve under permanent dynamic control on the navigation screen without further intra-operative fluoroscopic imaging. A control intra-operative 3D scan was used to observe the position of the screws, while for didactic reasons another postoperative CT scan was done. RESULTS: Twenty screws were successfully inserted into the first sacral vertebral bodies of the 16 patients. No additional intra-operative and postoperative complications occurred. The average operation time was 80 minutes and the average intra-operative radiation time was 1.13 minutes. Four patients underwent bilateral iliosacral fixation with longer operation time (152 minutes) and radiation time (1.56 minutes). The post-operative 3D scanning showed good results. No screws penetrated into the sacral canal or foramen. The reduction of fracture or dislocation and the position of iliosacral screws were all judged satisfactory. CONCLUSION: Compared with the conventional fluoroscopy method, navigated percutaneous placement of iliosacral screws under intra-operative 3D imaging reduces the radiation time and improves the accuracy. It is feasible and useful though there are some disadvantages such as the inferior image quality compared to CT scan, prolonged operation time and higher overall cost.

Analysis of cytogenetic damage in rice seeds induced by energetic heavy ions on-ground and after spaceflight.

To analyze the biological effects of the space environment, we flew nine lines of rice seeds on the Chinese 20(th) recoverable satellite for a duration of 18 days. The same lines of seeds were also irradiated to low doses (2.0 mGy) of Carbon, or Neon or Iron ions (with different LET value of 13.3 keV/microm, 31 keV/microm and 500 keV/microm respectively) at National Institute of Radiological Sciences in Chiba, Japan. The total number of mitotic cells and chromosomal aberrations were analyzed. The mitotic index (MI) and the frequency of chromosomal aberration were evaluated in order to compare the cytogenetic damages from spaceflight and from exposure to similar doses of charged particle on the ground. The results of the present study show that the space environment and heavy energy ion can alter cell growth, and induce various chromosome aberrations including micronuclei, chromosomal bridges, fragments and laggards. With all the lines combined, the frequency of chromosome aberrations and MI in seeds flown in space are the highest. The effectiveness of cytogenetic damage from spaceflight (SP) and the heavy ion irradiations is SP > Fe > Ne > C.

Unassisted refolding of urea-denatured arginine kinase from shrimp Feneropenaeus chinensis: evidence for two equilibrium intermediates in the refolding pathway.

The refolding process and the equilibrium intermediates of urea-denatured arginine kinase (AK) were investigated by 1-anilino-8-naphthalenesulfonate (ANS) intrinsic fluorescence, far-UV circular dichroism (CD), size-exclusion chromatography (SEC), and enzymatic activity. In dilute denaturant, two equilibrium refolding intermediates (I and N') were discovered, and a refolding scheme of urea-denatured AK was proposed. During the refolding of urea-denatured AK, the fluorescence intensity increased remarkably, accompanied by a significant blue shift of the emission maximum and a pronounced increase in molar ellipticity of CD at 222 nm. The first folding intermediate (I) was inactive in urea solution ranging between 2.4 and 3.0 M. The second (N') existed between a 0.4- and 0.8-M urea solution, with slightly increased activity. Neither the blue shift emission maximum nor the molar ellipticity of CD at 222 nm showed significant changes in these two regions. The two intermediates were characterized by monitoring the ANS binding ability in various residual urea solutions, and two peaks of the emission intensity were observed in urea solutions of 0.6 and 2.8 M, respectively. The SEC results indicated that a distribution coefficient (K(D)) platform existed in urea solutions ranging between 2.4 and 3.0 M urea, suggesting that there was a similarly apparent protein profile and size in the urea solution region. The refolding kinetics showed that the urea-denatured AK was in two-phase refolding. Proline isomerization occurred in the unfolding process of AK, which blocked the slow phase of refolding. These results suggested that the refolding process of urea-denatured AK contained at the least two equilibrium refolding intermediates.

Patelloplasty versus traditional total knee arthroplasty for osteoarthritis.

The purpose of this study was to compare the clinical effects of patelloplasty and traditional patellar management in total knee arthroplasty (TKA) for osteoarthritis. A total of 152 patients with osteoarthritis treated with TKA between January 2004 and December 2005 were retrospectively studied. The patients were randomly divided into 2 groups: the patelloplasty group (group A; n=76) and the traditional treatment group (group B; n=76). Knee Society Score (KSS), Feller patellar score, Lonner patellar score, patient satisfaction, joint range of motion (ROM), and incidence of postoperative anterior knee pain were compared between the groups. Mean follow-up was 55 months (range, 48-71 months) for 132 patients, including 68 patients in group A and 64 in group B. Significant differences were found in KSS functional score, Feller patellar score, Lonner patellar score, and patient satisfaction, but no significant differences were found in ROM and total KSS score between the groups postoperatively. Group A obtained higher KSS scores and patient satisfaction than group B, with no significant difference in postoperative anterior knee pain. Postoperative radiographs revealed a significant difference in patellofemoral congruence between the groups. Patelloplasty relieves pain, enhances patient satisfaction, and improves function better than traditional patellar management in TKA with patellar nonresurfacing.

Cytogenetic effects of low doses of energetic carbon ions on rice after exposures of dry seeds, wet seeds and seedlings.

In order to investigate the biological effects of heavy ion radiation at low doses and the different radiosensitivities of growing and non-growing plants, rice at different lift stages (dry seed, wet seed and seedling) were exposed to carbon ions at doses of 0.02, 0.2, 2 and 20 Gy. Radiobiological effects on survival, root growth and mitotic activity, as well as the induction of chromosome aberrations in root meristem, were observed. The results show that radiation exposure induces a stimulatory response at lower dose and an inhibitory response at higher dose on the mitotic activity of wet seeds and seedlings. Cytogenetic damages are induced in both seeds and seedlings by carbon ion radiation at doses as low as 0.02 Gy. Compared with seedlings, seeds are more resistant to the lethal damage and the growth rate damage by high doses of carbon ions, but are more sensitive to cytogenetic damage by low doses of irradiation. Different types of radiation induced chromosome aberrations are observed between seeds and seedlings. Based on these results, the relationships between low dose heavy ion-induced biological effects and the biological materials are discussed.

Heavy genetic load associated with the subspecific differentiation of japonica rice (Oryza sativa ssp. japonica L.).

Genetic load in the genome of the model species, rice, was genetically dissected by mapping quantitative trait loci (QTLs) affecting the radiosensitivity of 226 recombinant inbred lines (RILs) to gamma-ray- and spaceflight-induced radiation. The parents and RILs varied considerably in their radiosensitivity to gamma-ray irradiation. A total of 28 QTLs affecting the two index traits, seedling height (SH) and seed fertility (SF), of radiosensitivity were identified. The japonica parent, Lemont, was much more sensitive to gamma-ray irradiation than the indica parent, Teqing, and its alleles at almost all QTLs were associated with increased radiosensitivity, suggesting a much higher genetic load in the japonica genome of rice. Six QTLs (QSh2a, QSh2b, QSh5a, QSh7, QSf3b, and QSf10b) were located in the genomic regions particularly sensitive to radiation and thus might represent possible 'mutation hot spots' in the japonica genome. Detailed characterization of these genomic regions may shed light on the evolution and subspecific differentiation of rice.