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The aim of this study was to investigate how peritoneal dialysis and other influencing factors affect patients' cognitive function.The 85 subjects in the study group were regular patients in our center. The control group included 88 age and gender matched healthy individuals who were with normal renal function. The study subjects' cognitive levels and related factors were analyzed using several screening instruments: the cognitive function was measured using the Montreal Cognitive Assessment Scale and statistical analysis was conducted based on the relevant data.The results showed that cognitive impairment was higher in peritoneal dialysis patients than in non-dialysis subjects. Age and educational background were single factors that affected cognitive function, which was more likely to be impaired at a higher age level and/or a lower educational level.Cognitive function can be impaired by peritoneal dialysis, and age and education levels are influencing factors.

Weightlessness-induced cardiovascular dysfunction can lead to physiological and pathological consequences. It has been shown that spaceflight or simulated microgravity can alter expression profiles of some microRNAs (miRNAs). Here, we attempt to identify the role of miRNAs in human umbilical vein endothelial cells (HUVECs) apoptosis under simulated microgravity. RNA-sequencing and quantitative real-time PCR (qRT-PCR) assays were used to identify differentially expressed miRNAs in HUVECs under simulated microgravity. Then we obtained the target genes of these miRNAs through target analysis software. Moreover, GO and KEGG enrichment analysis were performed. The effects of these miRNAs on HUVECs apoptosis were evaluated by flow cytometry, Western blot and Hoechst staining. Furthermore, we obtained the target gene of miR-27b-5p by luciferase assay, qRT-PCR and Western blot. Finally, we investigated the relationship between this target gene and miR-27b-5p in HUVECs apoptosis under normal gravity or simulated microgravity. We found 29 differentially expressed miRNAs in HUVECs under simulated microgravity. Of them, the expressions of 3 miRNAs were validated by qRT-PCR. We demonstrated that miR-27b-5p affected HUVECs apoptosis by inhibiting zinc fingers and homeoboxes 1 (ZHX1). Our results reported here demonstrate for the first time that simulated microgravity can alter the expression of some miRNAs in HUVECs and miR-27b-5p may protect HUVECs from apoptosis under simulated microgravity by targeting ZHX1.

Individuals exposed to long-term spaceflight often experience cardiovascular dysfunctions characterized by orthostatic intolerance, disability on physical exercise, and even frank syncope. Recent studies have showed that the alterations of cardiovascular system are closely related to the functional changes of endothelial cells. We have shown previously that autophagy can be induced by simulated microgravity in human umbilical vein endothelial cells (HUVECs). However, the mechanism of enhanced autophagy induced by simulated microgravity and its role in the regulation of endothelial function still remain unclear. We report here that 48 h clinorotation promoted cell migration in HUVECs by induction of autophagy. Furthermore, clinorotation enhanced autophagy by the mechanism of human murine double minute 2 (HDM2)-dependent degradation of cytoplasmic p53 at 26S proteasome, which results in the suppression of mechanistic target of rapamycin (mTOR), but not via activation of AMPK in HUVECs. These results support the key role of HDM2–p53 in direct downregulation of mTOR, but not through AMPK in microgravity-induced autophagy in HUVECs.

Numerous countermeasures have been proposed to minimize microgravity-induced physical deconditioning, but their benefits are limited. The present study aimed to investigate whether personalized aerobic exercise based on artificial gravity (AG) mitigates multisystem physical deconditioning. Fourteen men were assigned to the control group (n=6) and the countermeasure group (CM, n=8). Subjects in the CM group were exposed to AG (2 Gz at foot level) for 30 min twice daily, during which time cycling exercise of 80-95 % anaerobic threshold (AT) intensity was undertaken. Orthostatic tolerance (OT), exercise tests, and blood assays were determined before and after 4 days head-down bed rest (HDBR). Cardiac systolic function was measured every day. After HDBR, OT decreased to 50.9 % and 77.5 % of pre-HDBR values in control and CM groups, respectively. Exercise endurance, maximal oxygen consumption, and AT decreased to 96.5 %, 91.5 % and 91.8 % of pre-HDBR values, respectively, in the control group. Nevertheless, there were slight changes in the CM group. HDBR increased heart rate, sympathetic activity, and the pre-ejection period, but decreased plasma volume, parasympathetic activity and left-ventricular ejection time in the control group, whereas these effects were eliminated in the CM group. Aldosterone had no change in the control group but increased significantly in the CM group. Our study shows that 80-95 % AT aerobic exercise based on 2 Gz of AG preserves OT and exercise endurance, and affects body fluid regulation during short-term HDBR. The underlying mechanisms might involve maintained cardiac systolic function, preserved plasma volume, and improved sympathetic responses to orthostatic stress.

Astronauts exposed to a gravity-free environment experience cardiovascular deconditioning that causes post-spaceflight orthostatic intolerance and other pathological conditions. Endothelial dysfunction is an important factor responsible for this alteration. Our previous study showed enhanced autophagy in endothelial cells under simulated microgravity. The present study explored the cytoprotective role of autophagy under microgravity in human umbilical vein endothelial cells (HUVECs). We found that clinorotation for 48 h induced apoptosis and endoplasmic reticulum (ER) stress in HUVECs. ER stress and the unfolded protein response (UPR) partially contributed to apoptosis under clinorotation. Autophagy partially reduced ER stress and restored UPR signaling by autophagic clearance of ubiquitin-protein aggregates, thereby reducing apoptosis. In addition, the ER stress antagonist 4-phenylbutyric acid upregulated autophagy in HUVECs. Taken together, these findings indicate that autophagy plays a protective role against apoptosis under clinorotation by clearing protein aggregates and partially restoring the UPR.

Objective To explore the difference in level of first-aid capability and consciousness of the masses in different regions of China. Methods The survey was performed by filling the questionnaire on the "National Day of Emergency Platinum Ten Minutes" over the country China on October 10, 2014. The data were analyzed by SPSS 13.0 software. Results A total of 1580 questionnaires were returned from 16 cities, and among them 1422 were valid. The highest age of the subjects involved in the investigation was 83 years, the youngest 14 years, with the mean age 40.2 years. There were 483 men and 703 women, of whom 767(64.7%) had heard of the "platinum ten minutes" project. 57.8% people believed that the "platinum ten minutes" was their own affair. 52.0% of them offered that they would call the emergency system when met an emergency; 83.8% did not have the experience of dealing with an accident; only 53.2% of them had actively learned first aid knowledge from TV, training schools, newspapers, extracurricular training etc. 27.2% of the people thought that they were not able to deal with accident or emergency of their families. On the scene of an injury, only 30.4% of the people would be willing to deal with the accident only when they were asked to. The scores of the middle, northeast, coastal and northwest regions were 80, 70, 60 and 50 (P60 year were 90, 80, 70 and 50 (P

Objective Spaceflight is associated with cardiovascular deregulation. However, the influence of microgravity on the cardiovascular system and its mechanisms and countermeasures remain unknown. Our previous studies have demonstrated that transcutaneous electrical acupuncture stimulation (TEAS) is effective in improving orthostatic tolerance (OT). The purpose of this study was to determine if TEAS treatment can attenuate cardiovascular deconditioning induced by a 4-day −6° head-down bed rest (HDBR). Methods Fourteen healthy male subjects were randomly allocated to a control group (control, n=6, 4 days HDBR without countermeasures) and a TEAS treatment group (TEAS, n=8, 4 days HDBR with TEAS at Neiguan (PC6) for 30 min each day for 4 consecutive days during HDBR). OT, plasma hormones, plasma volume and heart rate variability were assessed before and after HDBR. Cardiac function and cerebral blood flow were measured before, during and after HDBR. Results The data showed that TEAS treatment mitigated the decrease in OT that was observed in the control group and cardiac function, alleviated autonomic dysfunction, and partially prevented plasma volume reduction after HDBR. Angiotensin II and aldosterone were significantly increased by 129.3% and 133.3% after HDBR in the TEAS group (pConclusions These results indicate that 30 min of daily TEAS treatment at PC6 is partially effective in maintaining OT, probably due to increased plasma volume-regulating hormones and activation of the peripheral sympathetic nervous system. TEAS treatment appears effective at reducing cardiovascular deconditioning induced by HDBR for 4 days. Trial Registration Number NCT02300207.

UNLABELLED Finger reconstruction distal to the proximal interphalangeal (PIP) joint is a challenging task for hand surgeons. Although extended reverse dorsal metacarpal artery (RDMA) flaps were described for coverage of finger defects, reports on repairs beyond the PIP joint are limited. The occurrence of venous congestion of the flaps and their treatments require further clarification. METHODS Extended RDMA flaps were used to cover the finger defects extending from the PIP joints to the fingertips in a series of 16 patients. The reconstructed fingers included the index, middle, ring, and little fingers; thumb reconstruction was not included in this study. The flap size ranged from 2.5×1.8 to 5×3 cm. A composite flap with a segment of tendon was applied for a complex reconstruction in 4 cases. Either superficial branch of radial nerve or dorsal branch of ulnar nerve was included in flap elevation because of its perineural vascular network contributing to the flap perfusion. The pivot point was located at the level of the middle point of the proximal phalanx, where the communicating branches between the proper palmar digital artery and the dorsal metacarpal artery exist. A teardrop skin pedicle was used to reduce the tension of the flap pedicle. RESULTS All flaps totally survived except that 1 flap had epidermal loss later salvaged by secondary skin grafting. Venous congestion occurred in the distal part of 5 flaps and was effectively relieved after multiple subcutaneous heparin injections. Neither of the 2 cases of nerve repair resulted in significant improvement in sensation. All donor sites were primarily closed. CONCLUSIONS Extended RDMA flaps can be effectively applied in the reconstruction of finger defects beyond PIP joint. Its advantages include a simple dissection, single-stage reconstruction, and preservation of digital artery and nerve. The donor site can be primarily closed if the flap width is less than 3 cm. Multiple subcutaneous heparin injection is a preferred solution in cases where venous congestion occurs in the flap.

To investigate the changes and significance of IL-37 in patients with sepsis. A total of 50 patients with sepsis between September 2016 and October 2017 at the intensive care unit (ICU) of the First Affiliated Hospital of Shihezi University School of Medicine were selected as the sepsis group, 30 age and sex-matched healthy controls were selected as the control group. The levels of IL-37 in serum were measured by enzyme-linked immunosorbent assay (ELISA) on day 1 and day 7 of the sepsis patients. The levels of serum IL-37 in the sepsis group on day 1 [(39.13 ± 34.35)pg/mL] were significantly higher than that in the control group [(23.75 ± 2.52)pg/mL] with significant difference (P .05). A correlation analysis showed that the levels of serum IL-37 and IL-1β were positively correlated. The level of IL-37 observed in sepsis was found to correlate with the severity of the inflammatory reaction. IL-37 could be an important cytokine in the control of sepsis by suppressing the production of pro-inflammatory cytokines.

Individuals exposed to extended periods of spaceflight or prolonged 6° head-down-tilt bed rest often suffer from health hazards represented by cardiovascular deconditioning. Many studies have reported that alterations in vascular endothelial cells contribute to cardiovascular dysfunction induced by microgravity. Autophagy, a lysosomal degradation pathway, serves an adaptive role for survival, differentiation, and development in cellular homeostasis, and can be triggered by various environmental stimuli. However, whether autophagy can be induced in endothelial cells by real or simulated microgravity remains to be determined. This study was designed to investigate the effects of simulated microgravity on the activation of autophagy in human umbilical vein endothelial cells (HUVECs). We report here that clinorotation, a simulated model of microgravity, enhances autophagosome formation, increases LC3 and beclin-1 expression, and promotes the conversion of LC3-I to LC3-II in HUVECs. These results demonstrate that simulated microgravity for 48 h activates autophagy of vascular endothelial cells.

Pharmacological method state is a method to explain the principle of Chinese herb according to its external phenomenon such as shape, color, texture, features, and so on. The natural attribute of Chinese herb include shape, color, texture, smell, harvesting time, medicinal parts, chemical components, and so on. Though both of them have different key points, the natural attribute of Chinese herb can also be used to explain its medicinal mechanism. Therefore, the correlation research between pharmacological method state and the natural attribute of Chinese herb has some significance.

The effect of fine-grained surface layers on the fatigue behavior of plain C–Mn steel plates is investigated. The plain C–Mn steel plates have been manufactured by a special thermo-mechanical controlled process (TMCP). For plates rolled by the special TMCP (designated special plates), the ferrite grain size approaches 5.5 μm in the surface layers and reaches 6.5 μm on average in the whole thickness of the plates, while for usually rolled plates (designated usual plates), the grain size is 15 μm on average in the whole thickness of the plates, without obvious difference between surface and central layers. Significant improvements of fatigue properties have been achieved by the ferrite grain refinement. Under the similar stress condition, the fatigue lifetime of the special plate is more than 10 times as long as that of the usual plate, and the first stage of fatigue crack propagation can be prolonged. With a similar lifetime of the usual plate under a load ratio R (σmin/σmax) approaching zero, the special plate can sustain a load 40 MPa higher than that of the usual plate. Furthermore, fatigue fractographs have been observed and analyzed by a scanning electron microscope (SEM).

Interstitial fluid flow, generated upon induced movement of extracellular fluid after mechanical loading, activates many signal transduction pathways in bone cells. The mechanisms of mechanobiology in bone tissue are still not clearly understood. Recently focal adhesion kinase (FAK) was shown to be involved in mechanotransduction in a number of cells. This study was designed to characterize the functional roles of FAK in mediating osteoblast response to mechanical steady-state fluid shear stress (FSS). We reported here that FSS (15 dynes/cm(2)) induced activation of FAK and formation of FAK·Grb2·Sos ternary complex in MG-63 cells, which was necessary for activation of the downstream mitogen-activated protein kinase pathway signaling molecules extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK). Our results also showed that transfection of FAK (F397Y) plasmid, a negative mutant of FAK, blocked the increased expression of binding factor alpha 1, osterix, osteocalcin and alkaline phosphatase induced by FSS in MG-63 cells. These results demonstrate that FAK signaling is critical for FSS-induced activation of ERK and JNK, and for promotion of osteoblast differentiation and osteogenesis via its association with Grb2/Sos complex.

We have shown previously that combined short-arm centrifuge and aerobic exercise training preserved several physiologically important cardiovascular functions in humans. We hypothesized that artificial gravity (AG) and exercise is effective to prevent changes of physical problems during head-down bed rest (HDBR). To test this hypothesis, 12 healthy male subjects had undergone 4 days of 6° HDBR. Six of them were exposed to AG of an alternating 2-min intervals of +1.0 and +2.0 Gz at foot level for 30 min twice per day with ergometric exercise of 40 W as a countermeasure during bed rest (CM group), while the remaining six served as untreated controls (no-CM group). Before and after 4 days of bed rest, leg venous hemodynamics was assessed by venous occlusion plethysmography and autonomic cardiovascular control estimated by power spectral analysis of blood pressure and heart rate. Further, orthostatic tolerance was evaluated by a 75° head-up tilt test and physical working capacity was surveyed by near maximal physical working capacity test before and after bed rest. The data showed that combined centrifuge and exercise applied twice daily for a total of 60 min during 4 days of HDBR prevented (a) a decrease in working capacity, (b) autonomic dysfunction (a decrease in the activity of parasympathetic cardiac innervation) and (c) an increase in leg venous flow resistance. The combination of a 30 min alternating of +1.0 and +2.0 Gz for twice per day of AG with 40 W ergometric exercise may offer a promising countermeasure to short duration simulated microgravity.

Alterations of nitric oxide contribute to post-flight orthostatic intolerance. The aim of this study was to investigate the changes of inducible nitric oxide synthase (iNOS) and the mechanisms underlying regulation of iNOS by simulated microgravity in human umbilical vein endothelial cells (HUVECs). Clinorotation, a simulated-model of microgravity, increased iNOS expression and promoter activity in HUVECs. The transactivations of NF-κB and AP-1 were suppressed by 24 h clinorotation. A key role for AP-1, but not NF-κB in the regulation of iNOS was shown. (1) PDTC, a NF-κB inhibitor, had no effect on clinorotation upregulation of iNOS. (2) SP600125, a JNK-specific inhibitor, which resulted in inhibition of AP-1 activity, enhanced the iNOS expression and promoter activity in clinorotation. (3) Overexpression of AP-1 remarkably attenuated the upregulation effect of clinorotation. These findings indicate that clinorotation upregulates iNOS in HUVECs by a mechanism dependent on suppression of AP-1, but not NF-κB. These results support a key role for AP-1 in the signaling of postflight orthostatic intolerance. J. Cell. Biochem. 107: 357–363, 2009. © 2009 Wiley-Liss, Inc.

Data from human and rodent studies have demonstrated that microgravity induces observed bone loss in real spaceflight or simulated experiments. The decrease of bone formation and block of maturation may play important roles in bone loss induced by microgravity. The aim of this study was to investigate the changes of proliferation and differentiation in bone marrow mesenchymal stem cells (BMSCs) induced by simulated microgravity and the mechanisms underlying it. We report here that clinorotation, a simulated model of microgravity, decreased proliferation and differentiation in BMSCs after exposure to 48 h simulated microgravity. The inhibited proliferation are related with blocking the cell cycle in G2/M and enhancing the apoptosis. While alterations of the osteoblast differentiation due to the decreased SATB2 expression induced by simulated microgravity in BMSCs.

Study area is located north Wazigou of Xiuyan jade mining area west extension, it has the North Wazigou jade ore-forming conditions are very similar. Based on the North Wazigou and Yu-long background of the two regions and the metallogenic geological conditions of the systems analysis, and summarized jade Metallogenesis, we can come to Yulong ore-forming region has good potential.

A questionnaire survey was performed for the first time to assess the prevalence of visual symptoms and G-induced loss of consciousness (G-LOC) due to +Gz exposure in the Chinese Air Force (CAF) to determine the effectiveness of current G tolerance training. Responses were received from 594 individuals. Among them, 302 reported at least one episode of some sort of symptoms related to +Gz, including 110 (18.5%) with visual blurring, 231 (38.9%) with greyout, 111 (18.7%) with blackout, and 49 (8.2%) with G-LOC. Incidences were most common in aircrew with 250–1,000 flying hours (53.6%) and were more prevalent in those with fewer on type flying hours (p < 0.001). The most common situation was reported between +5 and 5.9 Gz. The results indicate a fairly high prevalence of visual symptoms and G-LOC among Chinese Air Force aircrew. There remains considerable scope for +Gz education, particularly in the early centrifuge training and selection of rational physical exercises.

Increasing the sensitivity of glioblastoma cells to radiation is a promising approach to improve survival in patients with glioblastoma multiforme (GBM). This study aims to determine if serine/threonine phosphatase (protein phosphatase 6 (PP6)) is a molecular target for GBM radiosensitization treatment. The GBM orthotopic xenograft mice model was used in this study. Our data demonstrated that the protein level of PP6 catalytic subunit (PP6c) was upregulated in the GBM tissue from about 50% patients compared with the surrounding tissue or control tissue. Both the in vitro survival fraction of GBM cells and the patient survival time were highly correlated or inversely correlated with PP6c expression (R(2)=0.755 and -0.707, respectively). We also found that siRNA knockdown of PP6c reduced DNA-dependent protein kinase (DNA-PK) activity in three different GBM cell lines, increasing their sensitivity to radiation. In the orthotopic mice model, the overexpression of PP6c in GBM U87 cells attenuated the effect of radiation treatment, and reduced the survival time of mice compared with the control mice, while the PP6c knocking-down improved the effect of radiation treatment, and increased the survival time of mice. These findings demonstrate that PP6 regulates the sensitivity of GBM cells to radiation, and suggest small molecules disrupting or inhibiting PP6 association with DNA-PK is a potential radiosensitizer for GBM.

To analyze the computed tomographic (CT) features of invasive pulmonary fungal infections (IPFI) and evaluate the value of CT-guided percutaneous biopsy.Seventeen IPFI cases diagnosed by CT-guided percutaneous biopsy were recruited. The distribution, extent, density and size of IPFI were analyzed in correlation with the final diagnosis retrospectively. And the relationship with the causative factor of mycosis was also assessed.(1) Candida albicans (n = 7) and cryptococcosisaspergillus (n = 5) were identified. (2) It showed segmental on lobar consolidation within lung field (n = 6), mixture of patterns and nodule (n = 4) and mass (n = 7). (3) The overall diagnostic accuracy of fiberoptic bronchoscopy examination was 35.3%. (4) The incidence of complicated pneumothorax was 11.8% (2/17). These cases were self-limited without any special treatment.The CT findings of PFI are too complex to be easily distinguished from other diseases. And the CT-guided percutaneous is a safe and effective procedure.

Cardiovascular and musculoskeletal deconditioning occurring in long-term spaceflight requires new strategies to counteract these adverse effects. We previously reported that a short-arm centrifuge produced artificial gravity (AG), together with ergometer, has an approving effect on promoting cardiovascular function. The current study sought to investigate whether the cardiac and cerebrovascular functions were maintained and improved using a strategy of AG combined with exercise training on cardiovascular function during 4-day head-down bed rest (HDBR). Twelve healthy male subjects were assigned to a control group (CONT, n=6) and an AG combined with ergometric exercise training group (CM, n=6). Simultaneously, cardiac pumping and systolic functions, cerebral blood flow were measured before, during, and after HDBR. The results showed that AG combined with ergometric exercise caused an increase trend of number of tolerance, however, there was no significant difference between the two groups. After 4-day HDBR in the CONT group, heart rate increased significantly (59±6 vs 66±7 beats/min), while stroke volume (98±12 vs 68±13 mL) and cardiac output (6±1 vs 4±1 L/min) decreased significantly (p

Musculoskeletal and cardiovascular deconditioning occurring in long-term spaceflight gives rise to the needs to develop new strategies to counteract these adverse effects. Short-arm centrifuge combined with ergometer has been proposed as a strategy to counteract adverse effects of microgravity. This study sought to investigate whether the combination of short-arm centrifuge and aerobic exercise training have advantages over short-arm centrifuge or aerobic exercise training alone.One week training was conducted by 24 healthy men. They were randomly divided into 3 groups: (1) short-arm centrifuge training, (2) aerobic exercise training, 40 W, and (3) combined short-arm centrifuge and aerobic exercise training. Before and after training, the cardiac pump function represented by stroke volume, cardiac output, left ventricular ejection time, and total peripheral resistance was evaluated. Variability of heart rate and systolic blood pressure were determined by spectral analysis. Physical working capacity was surveyed by near maximal physical working capacity test.The 1-week combined short-arm centrifuge and aerobic exercise training remarkably ameliorated the cardiac pump function and enhanced vasomotor sympathetic nerve modulation and improved physical working capacity by 10.9% (P.05, n=8). In contrast, neither the short-arm centrifuge nor the aerobic exercise group showed improvements in these functions.These results demonstrate that combined short-arm centrifuge and aerobic exercise training has advantages over short-arm centrifuge or aerobic exercise training alone in influencing several physiologically important cardiovascular functions in humans. The combination of short-arm centrifuge and aerobic exercise offers a promising countermeasure to microgravity.

To observe the effects of repeated + Gz exposures on the apoptosis of myocyte in rats.Twelve male Sprague-Dawley rats were randomly divided into three groups: Control group, + 6Gz group and + 10Gz group. The rats of + Gz groups were exposed to + 6Gz for 3 min, + 10Gz for 3 min respectively, 1 b/d, 1 week. Four control rats were kept at the Earth gravity (1G) in the room with the centrifuge. All animals were anaesthetized and anatomies 1 day after the last exposure. Ventricular myocardium was studied by electron microscopy and terminal deoxynucleotide transferase-mediated dUTP nick end labeling (TUNEL) method.The apoptosis of myocyte in control group and + 6Gz group were scarcely observed by electron microscopy, while heterochromatin concentration and margination were observed in + 10Gz group. The apoptotic index of myocardium increased significantly in + 6Gz and + 10Gz group compared with that of the control group (P0.05) and showed the largest value in the + 10Gz group (P0.05).Repeated + Gz exposures may induce apoptosis in myocyte, and the number of apoptosis in myocyte increases gradually with the increase of G value.

A variety of nerve conduits incorporated with chemical and biological factors have been developed to further stimulate nerve regeneration. Although most of the nerve guides in studies are basically limited to bridge a short gap of nerve defect in rat models, it is vital to evaluate effects of conduits on nerve regeneration over distance greater than 20 mm, or more clinically relevant nerve gap lengths in higher mammals. In this study, a poly(lactide-co-glycolide) (PLGA) nerve conduit, treated with pulsed plasma and coated with ciliary neurotrophic factor (CNTF) as well as chitosan, was used to repair 25-mm-long canine tibial nerve defects in eighteen cross-bred dogs. The canines were randomly divided into three groups (n = 6), a 25-mm segment of the tibial nerve was removed and replaced by a PLGA/chitosan-CNTF nerve conduit, PLGA/chitoson conduit and autologous nerve grafts were performed as the control. The results were evaluated by general observation, eletromyogram testing, S-100 histological immunostaining, and image analysis at 3 months after operation. The histological results demonstrated that the PLGA/chitosan-CNTF conduits and PLGA/chitosan conduits were capable of leading the damaged axons through the lesioned area. Through the comparation of the three groups, the results in PLGA/chitosan-CNTF conduits group were better than that of PLGA/chitosan conduits group, while they were similar to autologous nerve grafts group. Therefore, CNTF-coated PLGA/chitosan nerve conduits could be an alternative artificial nerve conduit for nerve regeneration. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010.

Cerebral ischemia-reperfusion injury (IRI) is a complex process resulting in cellular damage and death. Many studies have reported that an ischemic preconditioning could induce protection against ischemic insult. However, the safety concerns and practical feasibility have limited the application of ischemia preconditioning in practice. Subsequently, a number of substances including endotoxin and cytokines etc. have proven effective in inducing ischemic tolerance in the neurocyte. Unfortunately, the application of these substances to the clinical practice of neurosurgery still remains questionable for their toxicity or side effects. Therefore, a novel therapy to protect against cerebral IRI requires further study. Several recent studies confirmed that repeated hyperbaric oxygen preconditioning (HBO-PC) prior to cerebral ischemia or spinal cord ischemia can provide neuroprotection. HBO as a therapeutic measure has been widely accepted for its convenience and safety. However, information about the mechanism of how this neuroprotection works is still very limited. We hypothesize that autophagy induction is involved in HBO-PC induced neuroprotection on IRI in neurocyte. The hypothesis reveals that autophagy may be a new therapeutic target for cerebral IRI.

Because cells are sensitive to mechanical forces,microgravity might act on stress-dependent cell changes. Regulation of focal adhesions (FAs) and cytoskeletal activity plays a role in cell maintenance, cell movement,and migration. Human MCF-7 cells were exposed to modeled microgravity (MMG) to test the hypothesis that migration responsiveness to microgravity is associated with cytoskeleton and FA anomalies. MMG acts on MCF-7 cells by disorganizing cytoskeleton filaments (microfilaments and microtubules). Microfilaments in MMG did not display their typical radial array. Likewise, microtubules were disrupted in MCF-7 cells within 4 h of initiation of MMG and were partly reestablished by 48 h. FAs generated inmicrogravity were less mature than those established in controls, shown by reduced FAs number and clustering. In parallel, MMG decreased kinases activity (such as FAK,PYK2, and ILK) of FAs in MCF-7 cells. The expression of both integrinbeta1 and integrinbeta4 were downregulated by MMG. We conclude that cytoskeletal alterations and FAs changes in MMG are concomitant with cell invasion and migration retardation. We suggest that reduced migration response in MCF-7 cells following MMG is linked to changes of cytoskeleton and FAs.

The present study was designed to observe the expression and distribution of connexin 43 (Cx43) in myocardium of rats after repeated positive acceleration (+Gz) exposures. Thirty six male Sprague-Dawley rats were randomly divided into 3 groups (n=12): control group, +6Gz group and +10Gz group. The rats in +6Gz group were exposed to +6Gz for 3 min daily, 1 week, while rats in +10Gz group were subjected to +10Gz for 3 min daily, 1 week. All animals were anaesthetized and necropsied immediately, 1 d, 3 d and 7 d after the last exposure. The expression and distribution of Cx43 in the ventricles of hearts were examined by immunohistochemistry and Western blot analysis. The immunohistochemistry results showed that in control group abundant expression of Cx43 was observed with intense punctate labelling confined to the intercalated disks between cardiomyocytes. After +Gz exposure, there was a loss of the immuno-reactivity of Cx43, which was consistent with Western blot results, and distribution changes of Cx43, with an increase of Cx43 in side-to-side gap junction and a decrease of Cx43 in end-to-end gap junction. Western blot analysis revealed that Cx43 expression was modified in response to different exposure program and different recovery time. The protein expressions of Cx43 were lower at 4 time points after exposure in either +6Gz or +10Gz groups compared with that in the control group (P0.001). Densitometry analysis of immunoblots revealed a decrease in the total amount of Cx43 signals immediately after exposure while an increase during the recovery time. After 7-day recovery, the amounts of Cx43 in two exposure groups were still lower than that in the control group (P0.001). The decrease of Cx43 expression in +10Gz group was more significant than that in +6Gz group. The results demonstrated that the expression decrease and distribution disturbance of Cx43 in the ventricles of rats after repeated +Gz exposures could be recovered. These findings facilitate our understanding of the mechanisms of arrhythmias caused by +Gz and provide new protective measures.

To explore the changes of cardiac function and lower body negative pressure tolerance after self-generated Lower Body Negative Pressure device training and provide experimental evidences for its appliance.Twelve healthy male subjects were randomly divided into two groups, and received training on two conditions for entirely closing the valve or opening to -30 mmHg of peak LBNP separately. The group A was trained for five days and three minutes per day. Heartfunction, HUT and tolerance of LBNP were measured in pre-training, 3 d and post-training. The group B was trained for ten days and five minutes each day. All the measurements that was the same as in group A were made.Heart function of group A decreased and tolerance of LBNP increased significantly (P0.05). In group B, heart function increased significantly after 8 days training, so did tolerance of LBNP.It suggested that lower body negative pressure tolerance could be improved by self-generated Lower Body Negative Pressure device training. The changes of cardiac function, however, were based on the project of training.

To explore the effect of different degrees of denitrogenation on decompression sickness.Twenty-four rabbits were randomly divided into control group, 100% oxygen inhalation 30 min group, 60 min group and 120 min group. The rabbits were anesthetized and ventilated by mechanical ventilator. After 0, 30, 60, and 120 min of denitrogenation by inhalation of 100% oxygen, the rabbits were exposed to 11000 m for 30 min. The gas bubbles generated in the body of rabbits were detected and monitored by a Doppler ultrasound detector over the precordium.Time to bubble appearance increased with time of 100% oxygen inhalation during altitude decompression. As compared with the control group, time to bubble appearance lengthened significantly in 100% oxygen inhalation 60 min and 120 min groups (P0.01). Time to bubble appearance was positively correlated with time of 100% oxygen inhalation (P0.01). Accumulative number of bubbles decreased with the time of 100% oxygen inhalation. As compared with the control group, accumulative number of bubbles decreased significantly in 100% oxygen inhalation of 60 min and 120 min groups (P0.01). Accumulative number of bubbles was negatively correlated with time of 100% oxygen inhalation (P0.01).Denitrogenation by inhalation of 100% oxygen for 60 min and 120 min may reduce the generation of gas bubbles in rabbits when decompressed to an altitude of 11000 m.

To develop a kind of self-generating lower body negative pressure device.The device consists of a flexible bellows, reinforced by several steel rings and sealed by gasproof adhesive plaster. An adjustable valve, a one-way flap valve, shoulder straps and handles are incorporated on the top of the bellows. The user's lower body was contained in the bellows. As the user's legs were extended, the bellows was elongated and the air pressure in it decreased.Negative pressures of -58, -46, -38 and -26 mm-Hg respectively was created with the adjustable inlet valve completely closed, one-quarter open, half open, or fully open.This self-generating lower body negative pressure device combines exercise and LBNP into one thing and is safe and easy to use. It might be used in preventing cardiovascular deconditioning during spaceflight or for anti-G training of pilots.

Endothelial cells are very sensitive to microgravity and the morphological and functional changes in endothelial cells are believed to be at the basis of weightlessness-induced cardiovascular deconditioning. It has been shown that the proliferation, migration, and morphological differentiation of endothelial cells play critical roles in angiogenesis. However, the influence of microgravity on the ability of endothelial cells to foster angiogenesis remains to be explored in detail. In the present study, we used a clinostat to simulate microgravity, and we observed tube formation, migration, and expression of endothelial nitric oxide synthase (eNOS) in human umbilical vein endothelial cells (HUVEC-C). Specific inhibitors of eNOS and phosphoinositide 3-kinase (PI3K) were added to the culture medium and gravity-induced changes in the pathways that mediate angiogenesis were investigated. After 24 h of exposure to simulated microgravity, HUVEC-C tube formation and migration were significantly promoted.This was reversed by co-incubation with the specific inhibitor of N-nitro-L-arginine methyl ester hydrochloride (eNOS). Immunofluorescence assay, RT-PCR, and Western blot analysis demonstrated that eNOS expression in the HUVEC-C was significantly elevated after simulated microgravity exhibition. Ultrastructure observation via transmission electron microscope showed the number of caveolae organelles in the membrane of HUVEC-C to be significantly reduced. This was correlated with enhanced eNOS activity. Western blot analysis then showed that phosphorylation of eNOS and serine/threonine kinase (Akt) were both up-regulated after exposure to simulated microgravity. However, the specific inhibitor of PI3K not only significantly downregulated the expression of phosphorylated Akt, but also downregulated the phosphorylation of eNOS. This suggested that the PI3K-Akt signal pathway might participate in modulating the activity of eNOS. In conclusion, the present study indicates that 24 h of exposure to simulated microgravity promote angiogenesis among HUVEC-C and that this process is mediated through the PI3K-Akt-eNOS signal pathway.

We propose a design for a simple broad-angle polarization beam splitter (PBS) consisting of two rows of dielectric cylinders with different space periods. The finite-difference time-domain method simulations show that TM polarized light is reflected totally by this PBS but TE polarized light passes through it freely in a broad incident angle range (from −50° to 50°). The PBS can work over a wide frequency range (from 0.22 × (c/a) to 0.28 × (c/a)) with a high efficiency. Moreover, the PBS structure has a novel capability of tolerance to large random disorder, which is very advantageous for practical applications. Even when a random disorder of 15%a (a is space period) is introduced into the radius and position of each cylinder, the PBS structure can still maintain almost the same good performance and high splitting efficiency.