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1.  Risk factors for bile leakage after primary closure following laparoscopic common bile duct exploration: a retrospective cohort study 
BMC Surgery  2017;17:1.
Abstraction
Background
Primary closure following laparoscopic common bile duct exploration (LCBDE) has been widely adopted because of the efficacy and safety in treatment of common bile duct (CBD) stones. However, the risk factors for bile leakage, the most common complication after primary closure, has not been clarified yet.
Methods
A retrospective cohort study of patients who underwent LCBDE with primary closure after choledochotomy between Feb. 2012 and Jun. 2016 was performed. Risk factors for bile leakage were identified by logistic regression inculding demographic factors, preoperative condition and surgical details.
Results
Between Feb. 2012 and Jun. 2016, a total of 265 LCBDE procedures were applied in our hospital and 141 patients with primary closure were included in this study. Bile leakage occurred in 11.3% (16/141) of these patients, and happened more frequently in patients with slender CBD (<1 vs ≥1 cm, 31.6% vs 7.0%, p = 0.04) and those managed by inexperienced surgeons (initial 70 cases vs later cases, 17.1% vs 5.6%, p = 0.04). After multivariable regression, the diameter of CBD [OR 95% CI, 3.799 (1.081–13.349), p = 0.04] and experience of surgeons [OR 95% CI, 4.228 (1.330–13.438), p = 0.03] were significantly related to bile leakage.
Conclusion
Slender CBD and inexperienced surgeons were the high risk factors for bile leakage after primary closure following LCBDE.
doi:10.1186/s12893-016-0201-y
PMCID: PMC5217550  PMID: 28056934
Laparoscopic common bile duct exploration; Primary closure; Bile leakage
2.  KIF2A regulates the spindle assembly and the metaphase I-anaphase I transition in mouse oocyte 
Scientific Reports  2016;6:39337.
KIF2A, a member of the kinesin-13 family, has been reported to play a role in spindle assembly in mitosis. However, its function in mammalian meiosis remains unknown. In this research, we examined the expression, localization and function of KIF2A during mouse oocyte meiosis. KIF2A was expressed in some key stages in mouse oocyte meiosis. Immunofluorescent staining showed that KIF2A distributed in the germinal vesicle at the germinal vesicle stage and as the spindle assembling after meiosis resumption, KIF2A gradually accumulated to the entire spindle. The treatment of oocytes with taxol and nocodazole demonstrated that KIF2A was co-localized with α-tubulin. Depletion of KIF2A by specific short interfering (si) RNA injection resulted in abnormal spindle assembly, failure of spindle migration, misaligned chromosomes and asymmetric cell division. Meanwhile, SKA1 expression level was decreased and the TACC3 localization was disrupted. Moreover, depletion of KIF2A disrupted the actin cap formation, arrested oocytes at metaphase I with spindle assembly checkpoint protein BubR1 activated and finally reduced the rate of the first polar body extrusion. Our data indicate that KIF2A regulates the spindle assembly, asymmetric cytokinesis and the metaphase I-anaphase I transition in mouse oocyte.
doi:10.1038/srep39337
PMCID: PMC5171862  PMID: 27991556
3.  The origin of ultrahigh piezoelectricity in relaxor-ferroelectric solid solution crystals 
Nature Communications  2016;7:13807.
The discovery of ultrahigh piezoelectricity in relaxor-ferroelectric solid solution single crystals is a breakthrough in ferroelectric materials. A key signature of relaxor-ferroelectric solid solutions is the existence of polar nanoregions, a nanoscale inhomogeneity, that coexist with normal ferroelectric domains. Despite two decades of extensive studies, the contribution of polar nanoregions to the underlying piezoelectric properties of relaxor ferroelectrics has yet to be established. Here we quantitatively characterize the contribution of polar nanoregions to the dielectric/piezoelectric responses of relaxor-ferroelectric crystals using a combination of cryogenic experiments and phase-field simulations. The contribution of polar nanoregions to the room-temperature dielectric and piezoelectric properties is in the range of 50–80%. A mesoscale mechanism is proposed to reveal the origin of the high piezoelectricity in relaxor ferroelectrics, where the polar nanoregions aligned in a ferroelectric matrix can facilitate polarization rotation. This mechanism emphasizes the critical role of local structure on the macroscopic properties of ferroelectric materials.
Combining a perovskite ferroelectric with moderate piezoelectric properties and a nonpiezoelectric pervoskite relaxor can create a highly piezoelectric material. Here, the authors help explain this unusual result by quantifying how polar nanoregions in the material contribute to its piezoelectric response.
doi:10.1038/ncomms13807
PMCID: PMC5187463  PMID: 27991504
4.  ASIC1a regulates insular long-term depression and is required for the extinction of conditioned taste aversion 
Nature Communications  2016;7:13770.
Acid-sensing ion channel 1a (ASIC1a) has been shown to play important roles in synaptic plasticity, learning and memory. Here we identify a crucial role for ASIC1a in long-term depression (LTD) at mouse insular synapses. Genetic ablation and pharmacological inhibition of ASIC1a reduced the induction probability of LTD without affecting that of long-term potentiation in the insular cortex. The disruption of ASIC1a also attenuated the extinction of established taste aversion memory without altering the initial associative taste learning or its long-term retention. Extinction of taste aversive memory led to the reduced insular synaptic efficacy, which precluded further LTD induction. The impaired LTD and extinction learning in ASIC1a null mice were restored by virus-mediated expression of wild-type ASIC1a, but not its ion-impermeable mutant, in the insular cortices. Our data demonstrate the involvement of an ASIC1a-mediated insular synaptic depression mechanism in extinction learning, which raises the possibility of targeting ASIC1a to manage adaptive behaviours.
The acid-sensing ion channel, ASIC1a, is known to play a role in synaptic transmission and plasticity. Here, the authors demonstrate a role for ASIC1a in regulating plasticity in the insular cortex and find that extinction of conditioned taste aversion memory is disrupted in the ASIC1a knockout mice.
doi:10.1038/ncomms13770
PMCID: PMC5150990  PMID: 27924869
5.  Aspirin down Regulates Hepcidin by Inhibiting NF-κB and IL6/JAK2/STAT3 Pathways in BV-2 Microglial Cells Treated with Lipopolysaccharide 
Aspirin down regulates transferrin receptor 1 (TfR1) and up regulates ferroportin 1 (Fpn1) and ferritin expression in BV-2 microglial cells treated without lipopolysaccharides (LPS), as well as down regulates hepcidin and interleukin 6 (IL-6) in cells treated with LPS. However, the relevant mechanisms are unknown. Here, we investigate the effects of aspirin on expression of hepcidin and iron regulatory protein 1 (IRP1), phosphorylation of Janus kinase 2 (JAK2), signal transducer and activator of transcription 3 (STAT3) and P65 (nuclear factor-κB), and the production of nitric oxide (NO) in BV-2 microglial cells treated with and without LPS. We demonstrated that aspirin inhibited hepcidin mRNA as well as NO production in cells treated with LPS, but not in cells without LPS, suppresses IL-6, JAK2, STAT3, and P65 (nuclear factor-κB) phosphorylation and has no effect on IRP1 in cells treated with or without LPS. These findings provide evidence that aspirin down regulates hepcidin by inhibiting IL6/JAK2/STAT3 and P65 (nuclear factor-κB) pathways in the cells under inflammatory conditions, and imply that an aspirin-induced reduction in TfR1 and an increase in ferritin are not associated with IRP1 and NO.
doi:10.3390/ijms17121921
PMCID: PMC5187761  PMID: 27999284
aspirin; hepcidin; P65 (nuclear factor-κB); IL-6/JAK2/STAT3 pathway; lipopolysaccharide (LPS); nitric oxide (NO); iron regulatory protein 1 (IRP1)
6.  Feasibility study of emergency intervention for vascular injury outside the hospital 
Background
Minimally invasive surgery in the field of traumatic vascular injury diagnosis and treatment has achieved good results. This study was designed to determine whether pre-hospital emergency intervention is feasible for vascular injury in a field intervention cabin under the condition of war or a disaster site.
Methods
Different types of animal experiments of vascular injury intervention were performed in a field intervention cabin. Treatment capacity was evaluated by data collection, including duration of surgery, clinical evaluation, image clarity, and equipment handling. Environmental adaptability and mobility were evaluated by maneuverability and long-distance mobility.
Results
A total of 56 surgeries (7 types) were performed in the field intervention cabin. Digital subtraction angiography (DSA) had good imaging performance. A total of 4800 km of long-distance mobility was performed, and all the equipment operated normally without any equipment failure. We participated in the medical service maneuver twice. The cabin unfolded and worked properly. There was no equipment damage during the medical service maneuver.
Conclusions
Use of a field intervention cabin under the conditions of war or disaster is feasible for pre-hospital emergency intervention of vascular injury.
doi:10.1186/s40779-016-0106-1
PMCID: PMC5127049  PMID: 27942389
Vascular injury; Pre-hospital emergency; Intervention; Cabin
7.  Crystal structures of translocator protein (TSPO) and mutant mimic of a human polymorphism 
Science (New York, N.Y.)  2015;347(6221):555-558.
The 18-kilodalton translocator protein (TSPO), proposed to be a key player in cholesterol transport into mitochondria, is highly expressed in steroidogenic tissues, metastatic cancer, and inflammatory and neurological diseases such as Alzheimer’s and Parkinson’s. TSPO ligands, including benzodiazepine drugs, are implicated in regulating apoptosis and are extensively used in diagnostic imaging. We report crystal structures (at 1.8, 2.4, and 2.5 angstrom resolution) of TSPO from Rhodobacter sphaeroides and a mutant that mimics the human Ala147→Thr147 polymorphism associated with psychiatric disorders and reduced pregnenolone production. Crystals obtained in the lipidic cubic phase reveal the binding site of an endogenous porphyrin ligand and conformational effects of the mutation. The three crystal structures show the same tightly interacting dimer and provide insights into the controversial physiological role of TSPO and how the mutation affects cholesterol binding.
doi:10.1126/science.1260590
PMCID: PMC5125025  PMID: 25635101
8.  Translocator Protein 18 kDa (TSPO): An Old Protein with New Functions? 
Biochemistry  2016;55(20):2821-2831.
Translocator protein 18 kDa (TSPO) was previously known as the peripheral benzodiazepine receptor (PBR) in eukaryotes, where it is mainly localized to the mitochondrial outer membrane. Considerable evidence indicates that it plays regulatory roles in steroidogenesis and apoptosis and is involved in various human diseases, such as metastatic cancer, Alzheimer’s and Parkinson’s disease, inflammation, and anxiety disorders. Ligands of TSPO are widely used as diagnostic tools and treatment options, despite there being no clear understanding of the function of TSPO. An ortholog in the photosynthetic bacterium Rhodobacter was independently discovered as the tryptophan-rich sensory protein (TspO) and found to play a role in the response to changes in oxygen and light conditions that regulate photosynthesis and respiration. As part of this highly conserved protein family found in all three kingdoms, the rat TSPO is able to rescue the knockout phenotype in Rhodobacter, indicating functional as well as structural conservation. Recently, a major breakthrough in the field was achieved: the determination of atomic-resolution structures of TSPO from different species by several independent groups. This now allows us to reexamine the function of TSPO with a molecular perspective. In this review, we focus on recently determined structures of TSPO and their implications for potential functions of this ubiquitous multifaceted protein. We suggest that TSPO is an ancient bacterial receptor/stress sensor that has developed additional interactions, partners, and roles in its mitochondrial outer membrane environment in eukaryotes.
Graphical abstract
doi:10.1021/acs.biochem.6b00142
PMCID: PMC5125027  PMID: 27074410
9.  Identification of a Key Cholesterol Binding Enhancement Motif in Translocator Protein 18 kDa 
Biochemistry  2015;54(7):1441-1443.
Translocator protein 18 kDa (TSPO) in the mitochondrial outer membrane has been implicated in cholesterol transport regulating steroidogenesis. A human single polymorphism associated with anxiety disorders (A147T) and reduced pregnenolone production is adjacent to TSPO’s cholesterol binding motif. In a mutant mimicking this polymorphism, we observe a lower level of binding of cholesterol. Further, three residues preceding A147 are more hydrophilic in a bacterial TSPO that has an affinity for cholesterol 1000-fold lower than that of the human form. Converting these residues to the human form in the bacterial homologue strikingly increases the affinity for cholesterol. An important role for this extended motif is further supported by covariance analysis.
doi:10.1021/bi5015453
PMCID: PMC5125615  PMID: 25635829
10.  Genome Sizes of Nine Insect Species Determined by Flow Cytometry and k-mer Analysis 
The flow cytometry method was used to estimate the genome sizes of nine agriculturally important insects, including two coleopterans, five Hemipterans, and two hymenopterans. Among which, the coleopteran Lissorhoptrus oryzophilus (Kuschel) had the largest genome of 981 Mb. The average genome size was 504 Mb, suggesting that insects have a moderate-size genome. Compared with the insects in other orders, hymenopterans had small genomes, which were averagely about ~200 Mb. We found that the genome sizes of four insect species were different between male and female, showing the organismal complexity of insects. The largest difference occurred in the coconut leaf beetle Brontispa longissima (Gestro). The male coconut leaf beetle had a 111 Mb larger genome than females, which might be due to the chromosome number difference between the sexes. The results indicated that insect invasiveness was not related to genome size. We also determined the genome sizes of the small brown planthopper Laodelphax striatellus (Fallén) and the parasitic wasp Macrocentrus cingulum (Brischke) using k-mer analysis with Illunima Solexa sequencing data. There were slight differences in the results from the two methods. k-mer analysis indicated that the genome size of L. striatellus was 500–700 Mb and that of M. cingulum was ~150 Mb. In all, the genome sizes information presented here should be helpful for designing the genome sequencing strategy when necessary.
doi:10.3389/fphys.2016.00569
PMCID: PMC5121235  PMID: 27932995
genome size; flow cytometry; k-mer analysis; sex difference; insect invasiveness
11.  Ovarian thecoma-fibroma groups: clinical and sonographic features with pathological comparison 
Background
Ovarian thecoma-fibroma groups (OTFG) are uncommon sex cord-stromal neoplasms. The objective of the study was to demonstrate clinical and sonographic features of OTFG and compare with surgical histopathology.
Methods
A total of 61 patients with surgically proven OTFG were enrolled in this retrospective study to demonstrate its clinical and sonographic features and to compare with pathological findings. Gray scale and color Doppler sonography were performed presurgically with either transabdominal or transvaginal approach to image pelvic structures and lesions. The clinical findings and sonographic appearances were compared with the types of the OTFG tumors based on the histopathological diagnosis.
Results
The mean patient age was 53.57 (range, 26–86) years. There were 63.93% (39/61) patients in postmenopausal and 63.93% (39/61) patients with no clinical symptoms. Ultrasound findings of OTFG revealed as solid tumors with a typical feature of well-demarcated hypoechoic masses in 70.49% (43/61), among which 74.41% (32/43) tumors were smaller than 5 cm in diameter. There were 17 mixed echogenic masses with calcification, hemorrhage, or cyst, among which 70.59% (12/17) lesions were larger than 5 cm in diameter. Acoustic attenuation of the tumor was presented in 44.26% (27/61) of the cases. Doppler flow signals within the tumors were found in 20 cases (32.79%), in which 80% (16/20) had minimal or moderate flow signals. Ascites was detected in 32.79% (20/61) of the cases, Megi’s syndrome was found in 1 case. Final pathology revealed 41 (67.21%) thecoma-fibromas, 15 (24.59%) fibromas, 4 (6.56%) thecomas and 1 (1.64%) fibrosarcoma. There were 58 patients underwent cancer antigen 125 (CA125) test, and 20.69% (12/58) showed an elevated level. The diameter of tumors was found to be significantly correlated with CA125 level (p < 0.01) and the amount of ascites fluid (p < 0.05).
Conclusions
The typical sonographic features of OTFG include adnexal hypoechoic masses with clear border and acoustic attenuation as well as minimal Doppler flow signals. All the aforementioned features could make ultrasound imaging as a assistent tool improve the preoperative diagnostic accuracy.
doi:10.1186/s13048-016-0291-2
PMCID: PMC5120502  PMID: 27876070
Thecoma; Fibroma; Ovarian neoplasms; Ultrasound; Pathology
12.  The diagnosis and treatment of Rapunzel syndrome 
Acta Radiologica Open  2016;5(11):2058460115627660.
Trichobezoars are hairballs or hair-like fibers formed by chewing and swallowing hair or any other indigestible materials. Trichobezoars usually form in the gastric body and are thus prepyloric. However, trichobezoars may rarely pass through the pylorus into the duodenum, jejunum, ileum, and even the colon, in a condition referred to as Rapunzel syndrome. Here, we present a case of a 13-year-old girl with this rare syndrome and discuss the diagnosis and treatment of the disease.
doi:10.1177/2058460115627660
PMCID: PMC5122172  PMID: 27900201
Trichobezoars; Rapunzel syndrome; diagnosis; treatment
13.  Altered functional connectivity in the brain default-mode network of earthquake survivors persists after 2 years despite recovery from anxiety symptoms 
Although acute impact of traumatic experiences on brain function in disaster survivors is similar to that observed in post-traumatic stress disorders (PTSD), little is known about the long-term impact of this experience. We have used structural and functional magnetic resonance imaging to investigate resting-state functional connectivity and gray and white matter (WM) changes occurring in the brains of healthy Wenchuan earthquake survivors both 3 weeks and 2 years after the disaster. Results show that while functional connectivity changes 3 weeks after the disaster involved both frontal–limbic–striatal and default-mode networks (DMN), at the 2-year follow-up only changes in the latter persisted, despite complete recovery from high initial levels of anxiety. No gray or WM volume changes were found at either time point. Taken together, our findings provide important new evidence that while altered functional connectivity in the frontal–limbic–striatal network may underlie the post-trauma anxiety experienced by survivors, parallel changes in the DMN persist despite the apparent absence of anxiety symptoms. This suggests that long-term changes occur in neural networks involved in core aspects of self-processing, cognitive and emotional functioning in disaster survivors which are independent of anxiety symptoms and which may also confer increased risk of subsequent development of PTSD.
doi:10.1093/scan/nsv040
PMCID: PMC4631147  PMID: 25862672
default-mode network; functional magnetic resonance imaging; graph theory; trauma; stress
14.  Citrulline as a biomarker in the murine total-body irradiation model: correlation of circulating and tissue citrulline to small intestine epithelial histopathology 
Health physics  2015;109(5):452-465.
The use of plasma citrulline as a biomarker for gastrointestinal acute radiation syndrome via exposure to total-body irradiation in a murine model was investigated. The radiation exposure covered lethal, mid-lethal, and sub-lethal gastrointestinal acute radiation syndrome. Plasma citrulline profiles were generated over the first 6 days following total-body irradiation exposure of 6–15 Gy. In addition, plasma citrulline was comprehensively evaluated in the context of matching small intestine citrulline and histopathology. Higher plasma citrulline was significantly associated with lower irradiation doses over the first 6 days following the irradiation insult. Furthermore, higher plasma citrulline was significantly associated with higher crypt survival. The correlation of the plasma citrulline to crypt survival was more robust for higher irradiation doses and for later time points. The data suggested plasma citrulline was most informative for reflecting gastrointestinal injury resulting from exposure to 9–15 Gy total-body irradiation covering time-points 2 to 5 days post the irradiation insult.
doi:10.1097/HP.0000000000000346
PMCID: PMC4727745  PMID: 26425905
biological indicators; radiation damage; gastrointestinal tract; whole body irradiation
15.  Characterization of variations in IL23A and IL23R genes: possible roles in multiple sclerosis and other neuroinflammatory demyelinating diseases 
Aging (Albany NY)  2016;8(11):2734-2744.
Multiple sclerosis is among the most serious inflammatory demyelinating diseases (IDD). Interleukin-23A (IL23A) regulates and coordinates the activities of immune cells by interacting with its receptor IL23R and plays key roles in the pathogenesis of immune inflammatory diseases. IDD, deemed to be a kind of autoimmune diseases, may involve IL23A in the pathogenesis. The aim of this work was to validate the hypothesized involvement of IL-23A and its receptor in IDD. We sequenced the IL-23A and IL-23R genes for 206 Chinese Han IDD patients and evaluated SNPs within or near those genes. The serum levels of IL23A in IDD participants were analyzed using ELISA. The statistical analyses were conducted using Chi-Square Tests as implemented in SPSS (version 19.0). The Hardy-Weinberg equilibrium test of the population was carried out using online software OEGE. Three variants rs2066808, rs2371494, rs11575248 in IL-23A gene and one variant rs1884444 in IL-23R gene were demonstrated to be associated with the risk of MS or other IDD diseases, and the expression level of serum IL-23A in the MS patients was also altered. We conclude that variants in IL-23A and IL-23R genes were associated with the risk of MS or other IDD diseases.
doi:10.18632/aging.101058
PMCID: PMC5191866  PMID: 27893410
multiple sclerosis; IDD; interleukin-23A; gene expression level; SNP
16.  Asymmetric Spread of SRBSDV between Rice and Corn Plants by the Vector Sogatella furcifera (Hemiptera: Delphacidae) 
PLoS ONE  2016;11(10):e0165014.
Plant viruses are mostly transmitted by sucking insects via their piercing behaviors, which may differ due to host plant species and their developmental stages. We characterized the transmission of a fijivirus, southern rice black-streaked dwarf virus (SRBSDV), by the planthopper vector Sogatella furcifera Horváth (Hemiptera: Delphacidae), between rice and corn plants of varying developmental stages. SRBSDV was transmitted from infected rice to uninfected corn plants as efficiently as its transmission between rice plants, while was acquired by S. furcifera nymphs at a much lower rate from infected corn plants than from infected rice plants. We also recorded a high mortality of S. furcifera nymphs on corn plants. It is evident that young stages of both the virus donor and recipient plants added to the transmission efficiency of SRBSDV from rice to corn plants. Feeding behaviors of the vector recorded by electrical penetration graph showed that phloem sap ingestion, the behavioral event that is linked with plant virus acquisition, was impaired on corn plants, which accounts for the high mortality of and low virus acquisition by S. furcifera nymphs on corn plants. Our results reveal an asymmetric spread of SRBSDV between its two host plants and the underlying behavioral mechanism, which is of significance for assessing SRBSDV transmission risks and field epidemiology, and for developing integrated management approaches for SRBSDV disease.
doi:10.1371/journal.pone.0165014
PMCID: PMC5070867  PMID: 27760223
17.  Pulmonary rehabilitation coupled with negative pressure ventilation decreases decline in lung function, hospitalizations, and medical cost in COPD 
Medicine  2016;95(41):e5119.
Supplemental Digital Content is available in the text
Abstract
Pulmonary rehabilitation (PR) brings benefits to patients with chronic obstructive pulmonary disease (COPD). Negative pressure ventilation (NPV) increases ventilation and decreases hyperinflation as well as breathing work in COPD. We evaluated the long-term effects of a hospital-based PR program coupled with NPV support in patients with COPD on clinical outcomes.
One hundred twenty-nine patients with COPD were followed up for more than 5 years, with the NPV group (n = 63) receiving the support of NPV (20–30 cm H2O delivery pressure for 60 min) and unsupervised home exercise program of 20 to 30 min daily walk, while the control group (n = 6) only received unsupervised home exercise program. Pulmonary function tests and 6 min walk tests (6MWT) were performed every 3 to 6 months. Emergency room (ER) visits and hospitalization with medical costs were recorded.
A significant time-by-group interaction in the yearly decline of forced expiratory volume in 1 s in the control group analyzed by mixed-model repeated-measure analysis was found (P = 0.048). The 6MWT distance of the NPV group was significantly increased during the first 4 years, with the interaction of time and group (P = 0.003), the time alone (P = 0.014), and the quadratic time (P < 0.001) being significant between the 2 groups. ER exacerbations and hospitalizations decreased by 66% (P < 0.0001) and 54% (P < 0.0001) in the NPV group, respectively. Patients on PR program coupled with NPV had a significant reduction of annual medical costs (P = 0.022).
Our hospital-based multidisciplinary PR coupled with NPV reduced yearly decline of lung function, exacerbations, and hospitalization rates, and improved walking distance and medical costs in patients with COPD during a 5-year observation
doi:10.1097/MD.0000000000005119
PMCID: PMC5072959  PMID: 27741132
6 min walk test; chronic obstructive pulmonary disease; hospitalization; lung function; negative pressure ventilation; pulmonary rehabilitation
18.  Determinants of carbon release from the active layer and permafrost deposits on the Tibetan Plateau 
Nature Communications  2016;7:13046.
The sign and magnitude of permafrost carbon (C)-climate feedback are highly uncertain due to the limited understanding of the decomposability of thawing permafrost and relevant mechanistic controls over C release. Here, by combining aerobic incubation with biomarker analysis and a three-pool model, we reveal that C quality (represented by a higher amount of fast cycling C but a lower amount of recalcitrant C compounds) and normalized CO2–C release in permafrost deposits were similar or even higher than those in the active layer, demonstrating a high vulnerability of C in Tibetan upland permafrost. We also illustrate that C quality exerts the most control over CO2–C release from the active layer, whereas soil microbial abundance is more directly associated with CO2–C release after permafrost thaw. Taken together, our findings highlight the importance of incorporating microbial properties into Earth System Models when predicting permafrost C dynamics under a changing environment.
Permafrost stores large quantities of carbon (C), but uncertainty surrounds decomposability differences between active and permafrost layers. Here, Chen et al. use incubation experiments and a 3-pool model to find permafrost layers are equally or more labile, contributing to C vulnerability in Tibetan permafrost.
doi:10.1038/ncomms13046
PMCID: PMC5059472  PMID: 27703168
19.  Preparation and evaluation of a self-nanoemulsifying drug delivery system loaded with Akebia saponin D–phospholipid complex 
Background
Akebia saponin D (ASD) exerts various pharmacological activities but with poor oral bioavailability. In this study, a self-nanoemulsifying drug delivery system (SNEDDS) based on the drug–phospholipid complex technique was developed to improve the oral absorption of ASD.
Methods
ASD–phospholipid complex (APC) was prepared using a solvent-evaporation method and characterized by infrared spectroscopy, differential scanning calorimetry, morphology observation, and solubility test. Oil and cosurfactant were selected according to their ability to dissolve APC, while surfactant was chosen based on its emulsification efficiency in SNEDDS. Pseudoternary phase diagrams were constructed to determine the optimized APC-SNEDDS formulation, which was characterized by droplet size determination, zeta potential determination, and morphology observation. Robustness to dilution and thermodynamic stability of optimized formulation were also evaluated. Subsequently, pharmacokinetic parameters and oral bioavailability of ASD, APC, and APC-SNEDDS were investigated in rats.
Results
The liposolubility significantly increased 11.4-fold after formation of APC, which was verified by the solubility test in n-octanol. Peceol (Glyceryl monooleate [type 40]), Cremophor® EL (Polyoxyl 35 castor oil), and Transcutol HP (Diethylene glycol monoethyl ether) were selected as oil, surfactant, and cosurfactant, respectively. The optimal formulation was composed of Glyceryl monooleate (type 40), Polyoxyl 35 castor oil, Diethylene glycol monoethyl ether, and APC (1:4.5:4.5:1.74, w/w/w/w), which showed a particle size of 148.0±2.7 nm and a zeta potential of −13.7±0.92 mV after dilution with distilled water at a ratio of 1:100 (w/w) and good colloidal stability. Pharmacokinetic studies showed that APC-SNEDDS exhibited a significantly greater Cmax1 (733.4±203.8 ng/mL) than ASD (437.2±174.2 ng/mL), and a greater Cmax2 (985.8±366.6 ng/mL) than ASD (180.5±75.1 ng/mL) and APC (549.7±113.5 ng/mL). Compared with ASD, Tmax1 and Tmax2 were both remarkably shortened by APC-SNEDDS. The oral bioavailability in rats was enhanced significantly to 183.8% and 431.8% by APC and APC-SNEDDS, respectively.
Conclusion
These results indicated that APC-SNEDDS was a promising drug delivery system to enhance the oral bioavailability of ASD.
doi:10.2147/IJN.S108765
PMCID: PMC5045231  PMID: 27713630
Akebia saponin D; phospholipid complex; self-nanoemulsifying drug delivery systems; oral bioavailability
20.  Gastrodin ameliorates subacute phase cerebral ischemia-reperfusion injury by inhibiting inflammation and apoptosis in rats 
Molecular Medicine Reports  2016;14(5):4144-4152.
Gastrodin (GAS), which is extracted from the Chinese herbal medicine Gastrodia elata Blume, has long been used to improve stroke, epilepsy, dizziness and dementia. However, the effects and underlying mechanisms of GAS on subacute phase cerebral ischemia-reperfusion (I/R) injury remain unknown. The aim of the present study was to investigate the effects and mechanisms of GAS on cerebral I/R injury in rats. The rats were pretreated with GAS by gavage for 7 days followed by I/R surgery, and were then treated with GAS for 7 days after I/R surgery. Neurological deficits were assessed on days 1, 3 and 7 post-cerebral I/R injury. 2,3,5-Triphenyltetrazolium chloride staining was using to measure the infarct volume; morphological alterations were observed by hematoxylin and eosin staining under an optical microscope; apoptosis in the hippocampus and cortex was observed by terminal deoxynucleotidyl transferase dUTP nick end labeling staining; and the level of mRNA and protein expression was tested by reverse transcription-quantitative polymerase chain reation and western blot analysis, respectively. GAS markedly attenuated I/R-induced disability and histological damage, alleviated neuronal apoptosis, and reduced the mRNA and protein expression levels of inflammatory and proapoptotic factors, including interleukin-1β, cyclooxygenase-2, inducible nitric oxide synthase and cleaved caspase-3. These findings suggested that GAS may ameliorate subacute phase cerebral I/R injury by inhibiting inflammation and apoptosis in rats; therefore, GAS may be considered a potential candidate for the treatment of cerebral ischemia.
doi:10.3892/mmr.2016.5785
PMCID: PMC5101922  PMID: 27748849
gastrodin; inflammation; apoptosis; neuroprotection; rat
21.  Weyl magnons in breathing pyrochlore antiferromagnets 
Nature Communications  2016;7:12691.
Frustrated quantum magnets not only provide exotic ground states and unusual magnetic structures, but also support unconventional excitations in many cases. Using a physically relevant spin model for a breathing pyrochlore lattice, we discuss the presence of topological linear band crossings of magnons in antiferromagnets. These are the analogues of Weyl fermions in electronic systems, which we dub Weyl magnons. The bulk Weyl magnon implies the presence of chiral magnon surface states forming arcs at finite energy. We argue that such antiferromagnets present a unique example, in which Weyl points can be manipulated in situ in the laboratory by applied fields. We discuss their appearance specifically in the breathing pyrochlore lattice, and give some general discussion of conditions to find Weyl magnons, and how they may be probed experimentally. Our work may inspire a re-examination of the magnetic excitations in many magnetically ordered systems.
It was recently demonstrated that particular materials with non-trivial electronic band structure support quasiparticle excitations described by the relativistic Weyl equation. Here, the authors explore how an analogous magnonic band structure may exist in breathing pyrochlore antiferromagnets.
doi:10.1038/ncomms12691
PMCID: PMC5036007  PMID: 27650053
22.  Exercise Alters Gait Pattern but Not Knee Load in Patients with Knee Osteoarthritis 
BioMed Research International  2016;2016:7468937.
Six female patients with bilateral medial knee OA and 6 healthy controls were recruited. Patients with knee OA received a 6-week physiotherapist-supervised and home-based exercise program. Outcome measures, including the Western Ontario and McMaster Universities Arthritis Index and Short Form-36 Health Survey as well as objective biomechanical indices were obtained at baseline and follow-up. After treatment, no significant difference was observed in the knee abductor moment (KAM), lever arm, and ground reaction force. We, however, observed significantly improved pain and physical function as well as altered gait patterns, including a higher hip flexor moment and hip extension angle with a faster walking speed. Although KAM was unchanged, patients with bilateral knee OA showed an improved walking speed and altered the gait pattern after 6 weeks of supervised exercise. This finding suggests that the exercise intervention improves proximal joint mechanics during walking and can be considered for patients with bilateral knee OA. Non-weight-bearing strengthening without external resistance combined with stretching exercise may be an option to improve pain and function in individuals with OA who cannot perform high resistance exercises owing to pain or other reasons.
doi:10.1155/2016/7468937
PMCID: PMC5048036  PMID: 27725941
23.  The Role of Stem Cells in the Etiology and Pathophysiology of Endometriosis 
Seminars in reproductive medicine  2015;33(5):333-340.
Human endometrium is a dynamic organ that normally undergoes repetitive cyclic regeneration. To enable this rapid regeneration, it is not surprising that the endometrium contains a reservoir of progenitor stem cells. However, this pool of cells that allows the growth of the endometrium also allows for unrestrained growth that can reach beyond the endometrium. In this review, we will address the role of stem cells in endometriosis. Recent characterization of stem cell populations within human endometrium has opened the possibility of understanding their physiologic as well as their pathologic roles. While stem cells are critical to the cyclic regeneration of a healthy endometrium, we have shown that both endometrium-derived and bone marrow-derived stem cells can migrate to ectopic sites and contribute to the development of endometriosis. Furthermore, endometriosis interferes with the normal stem cell trafficking to the uterus that is necessary for endometrial growth and repair. Altered stem cell mobility and engraftment characterize this disease.
doi:10.1055/s-0035-1564609
PMCID: PMC4986990  PMID: 26375413
endometrium; endometriosis; stem cells; inflammation
24.  Perspective: Evolving understanding of translocator protein 18 kD (TSPO) 
Pharmacological research  2015;99:404-409.
The translocator protein 18 kD (TSPO) has been the focus of intense research by the biomedical community and the pharmaceutical industry because of its apparent involvement in many disease-related processes. These include steroidogenesis, apoptosis, inflammation, neurological disease and cancer, resulting in the use of TSPO as a biomarker and its potential as a drug target. Despite more than 30 years of study, the precise function of TSPO remains elusive. A recent breakthrough in determining the high-resolution crystal structures of bacterial homologs of mitochondrial TSPO provides new insight into the structural and functional properties at a molecular level and new opportunities for investigating the significance of this ancient and highly conserved protein family. The availability of atomic level structural information from different species also provides a platform for structure-based drug development. Here we briefly review current knowledge regarding TSPO and the implications of the new structures with respect to hypotheses and controversies in the field.
doi:10.1016/j.phrs.2015.03.022
PMCID: PMC4567528  PMID: 25882248
Translocator protein 18 kD (TSPO); crystal structure; ligand binding; porphyrin; cholesterol; benzodiazepine drugs; steroid hormones; VDAC; stress response
25.  Effects of early feeding on the host rumen transcriptome and bacterial diversity in lambs 
Scientific Reports  2016;6:32479.
Early consumption of starter feed promotes rumen development in lambs. We examined rumen development in lambs fed starter feed for 5 weeks using histological and biochemical analyses and by performing high-throughput sequencing in rumen tissues. Additionally, rumen contents of starter feed-fed lambs were compared to those of breast milk-fed controls. Our physiological and biochemical findings revealed that early starter consumption facilitated rumen development, changed the pattern of ruminal fermentation, and increased the amylase and carboxymethylcellulase activities of rumen micro-organisms. RNA-seq analysis revealed 225 differentially expressed genes between the rumens of breast milk- and starter feed-fed lambs. These DEGs were involved in many metabolic pathways, particularly lipid and carbohydrate metabolism, and included HMGCL and HMGCS2. Sequencing analysis of 16S rRNA genes revealed that ruminal bacterial communities were more diverse in breast milk-than in starter feed-fed lambs, and each group had a distinct microbiota. We conclude that early starter feeding is beneficial to rumen development and physiological function in lambs. The underlying mechanism may involve the stimulation of ruminal ketogenesis and butanoate metabolism via HMGCL and HMGCS2 combined with changes in the fermentation type induced by ruminal microbiota. Overall, this study provides insights into the molecular mechanisms of rumen development in sheep.
doi:10.1038/srep32479
PMCID: PMC5006043  PMID: 27576848

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