[Meta-analysis of the role of fibular fixation in tibiofibular fractures].

OBJECTIVE: To compare the role and importance of fibular fixation in tibiofibular fractures by Meta-analysis. METHODS: The literature related to the comparison of the efficacy of fixation of the fibula with or without fixation on the treatment of tibiofibular fractures was searched through the databases of China Knowledge Network, Wipu, Wanfang, The Cochrane Library, Web of science and Pubmed, and statistical analysis was performed using RevMan 5.3 software. The rates of malrotation, rotational deformity, internal/external deformity, anterior/posterior deformity, non-union, infection, secondary surgery and operative time were compared between the fibula fixation and non-fixation groups. RESULTS: A total of 11 publications were included, six randomised controlled trials and five case-control trials, eight of which were of high quality. A total of 813 cases were included, of which 383 were treated with fibula fixation and 430 with unfixed fibulae.Meta-analysis results showed that fixation of the fibulae in the treatment of tibiofibular fractures reduced the rates of postoperative rotational deformity[RR=0.22, 95%CI(0.10, 0.45), P<0.000 1] and internal/external deformity[RR=0.34, 95%CI(0.14, 0.84), P=0.02] and promoted fracture healing [RR=0.76, 95%CI(0.58, 0.99), P=0.04]. In contrast, the rates of poor reduction [RR=0.48, 95% CI(0.10, 2.33), P=0.36], anterior/posterior deformity[RR=1.50, 95%CI(0.76, 2.96), P=0.24], infection[RR=1.43, 95%CI(0.76, 2.72), P=0.27], secondary surgery[RR=1.32, 95%CI(0.82, 2.11), P=0.25], and operative time[MD=10.21, 95%CI(-17.79, 38.21), P=0.47] were not statistically significant (P>0.05) for comparison. CONCLUSION: Simultaneous fixation of the tibia and fibula is clinically more effective in the treatment of tibiofibular fractures.

TMT quantitative proteomics reveals key proteins relevant to microRNA-1-mediated regulation in osteoarthritis.

Osteoarthritis (OA) is the second-commonest arthritis, but pathogenic and regulatory mechanisms underlying OA remain incompletely understood. Here, we aimed to identify the mechanisms associated with microRNA-1 (miR-1) treatment of OA in rodent OA models using a proteomic approach. First, N = 18 Sprague Dawley (SD) rats underwent sham surgery (n = 6) or ACL transection (n = 12), followed at an interval of one week by randomization of the ACL transection group to intra-articular administration of either 50 µL placebo (control group) or miR-1 agomir, a mimic of endogenous miR-1 (experimental group). After allowing for eight weeks of remodeling, articular cartilage tissue was harvested and immunohistochemically stained for the presence of MMP-13. Second, N = 30 Col2a1-cre-ERT2 /GFPf1/fl -RFP-miR-1 transgenic mice were randomized to intra-articular administration of either placebo (control group, N = 15) or tamoxifen, an inducer of miR-1 expression (experimental group, N = 15), before undergoing surgical disruption of the medial meniscus (DMM) after an interval of five days. After allowing for eight weeks of remodeling, articular cartilage tissue was harvested and underwent differential proteomic analysis. Specifically, tandem mass tagging (TMT) quantitative proteomic analysis was employed to identify inter-group differentially-expressed proteins (DEP), and selected DEPs were validated using real-time quantitative polymerase chain reaction (RT-qPCR) technology. Immunohistochemically-detected MMP-13 expression was significantly lower in the experimental rat group, and proteomic analyses of mouse tissue homogenate demonstrated that of 3526 identified proteins, 345 were differentially expressed (relative up- and down-regulation) in the experimental group. Proteins Fn1, P4ha1, P4ha2, Acan, F2, Col3a1, Fga, Rps29, Rpl34, and Fgg were the *top ten most-connected proteins, implying that miR-1 may regulate an expression network involving these proteins. Of these ten proteins, three were selected for further validation by RT-qPCR: the transcript of Fn1, known to be associated with OA, exhibited relative upregulation in the experimental group, whereas the transcripts of P4ha1 and Acan exhibited relative downregulation. These proteins may thus represent key miR-1 targets during OA-regulatory mechanisms, and may provide additional insights regarding therapeutic mechanisms of miR-1 in context of OA.

Synergy of Platinum Single Atoms and Platinum Atomic Clusters on Sulfur-Doped Titanium Nitride Nanotubes for Enhanced Hydrogen Evolution Reaction.

Highly dispersed Pt, such as Pt single atoms and atomic clusters, has great potential in the electrocatalytic hydrogen evolution reaction (HER) due to the high atomic efficiency and unique electronic configuration. Rationally regrating the electronic structure of Pt catalysts is desirable for promoting the HER performance. Herein, a 3D self-supported monolithic electrode consisting of Pt single atoms (PtSAs ) and Pt atomic clusters (PtACs ) anchored on sulfur-doped titanium nitride nanotubes (S-TiN NTs) encapsulated in polyaniline (PANI) on Ti mesh (PANI@Pt/S-TiN NTs/Ti) via a facile electrochemical strategy for efficient HER is designed and synthesized. Contributed by the unique structure and composition and the synergy of PtSAs , PtACs and S-TiN NTs, the PANI@Pt/S-TiN NTs/Ti electrode exhibits ultrahigh HER activities with only 12, 25 and 39 mV overpotentials at -10 mA cm-2 in acidic, alkaline and neutral media, respectively, and can maintain a stable performance for 25 h. Impressively, the mass activities are respectively up to 26.1, 22.4, and 17.7 times as that of Pt/C/CC electrode. Theoretical calculation results show that the synergistic effect of PtSAs , PtACs , and S-TiN NTs can optimize the electronic structure of Pt and generate multiple active sites with a thermodynamically favorable hydrogen adsorption free energy (ΔGH* ), thereby resulting in an enhanced HER activity.

MiR-1 is a critical regulator of chondrocyte proliferation and hypertrophy by inhibiting Indian hedgehog pathway during postnatal endochondral ossification in miR-1 overexpression transgenic mice.

Endochondral bone formation from the growth plate plays a critical role in vertebrate limb development and skeletal homeostasis. Although miR-1 is mainly expressed in the hypertrophic region of the growth plate during this process, its role in the endochondral bone formation is unknown. To elucidate the role of miR-1 in cartilage development, chondrocyte-specific transgenic mice with high expression of miR-1 were generated (Col2a1-Cre-ERT2-GFPfl/fl-RFP-miR-1). Transgenic mice showed short limbs and delayed formation of secondary ossification centers. In the tibia growth plate of miR-1-overexpressing transgenic mice, the chondrocytes in the proliferative zone were disorganized and their proliferation decreased, and the ColX, MMP-13 and Indian Hedgehog (IHH) in chondrocytes showed a downward trend, resulting in decreased terminal differentiation in the hypertrophic zone. In addition, the apoptosis index caspase-3 also showed a downward trend in the tibia growth plate. It was concluded that miR-1 overexpression affects chondrocyte proliferation, hypertrophic differentiation, and apoptosis, thereby delaying the formation of secondary ossification centers and leading to short limbs. It was also verified that miR-1 affects endochondral ossification through the IHH pathway. The above results suggest that miR-1 overexpression can affect endochondral osteogenesis by inhibiting chondrocyte proliferation, hypertrophic differentiation, and apoptosis, thus causing limb hypoplasia in mice. This work gives potential for new therapeutic directions and insights for the treatment of dwarf-related diseases.

The Level of Histone Deacetylase 4 is Associated with Aging Cartilage Degeneration and Chondrocyte Hypertrophy.

Purpose: To determine the role of histone deacetylase 4 (HDAC4)-controlled chondrocyte hypertrophy in the onset and development of age-related osteoarthritis (OA). Methods: Morphological analysis of human knee cartilages was performed to observe structural changes during cartilage degeneration. HDAC4 expression was deleted in adult aggrecan (Acan)-CreERT2; HDAC4fl/fl transgenic mice. The onset and development of age-related OA were investigated in transgenic and control mice using hematoxylin and eosin (H&E) and Safranin O staining. Furthermore, the progression of ACLT-induced OA following adenovirus-mediated HDAC4 overexpression was explored in rats. The expression levels of genes related to hypertrophy, cartilage matrix and its digestion, and chondrocyte proliferation were investigated using qPCR. Immunohistochemistry (IHC) was used to explore the mechanisms underlying HDAC4-controlled age-related changes in OA progression. Results: In human cartilage, we performed morphological analysis and IHC, the results showed that hypertrophy-related structural changes are related to HDAC4 expression. Age-related OA was detected early (OARSI scores 2.7 at 8-month-old) following HDAC4 deletion in 2-month-old mice. Furthermore, qPCR and IHC results showed changes in hypertrophy-related genes Col10a1, Runx2 and Sox9 in chondrocytes, particularly in the expression of Runt-related transcription factor 2 (Runx2, 13.29±0.99 fold). The expression of the main cartilage matrix-related genes Col2a1 and Acan decreased, that of cartilage matrix digestion-related gene MMP-13 increased, while that of chondrocyte proliferation-related genes PTHrP, Ihh and Gli1 changed. In contrast, rat cartilage's qPCR and IHC results showed opposite outcomes after HDAC4 overexpression. Conclusion: Based on the results above, we concluded that HDAC4 expression regulates the onset and development of age-related OA by controlling chondrocyte hypertrophy. These results may help in the development of early diagnosis and treatment of age-related OA.

IGF-1 induces cellular senescence in rat articular chondrocytes via Akt pathway activation.

Cellular senescence decreases cell proliferation over time and is characterized by typical markers, including larger cell volume, a flattened morphology, irreversible cell cycle arrest, augmentation of senescence-associated ß-galactosidase (SA-ß-gal) activity and senescence-associated secretory phenotype. A variety of factors are implicated in the process of cellular aging, which mediates an organisms' lifespan. Insulin-like growth factor-1 (IGF-1) serves an essential role in regulating cell growth, division, proliferation and senescence. In the present study, the role of IGF-1 and the downstream Akt signaling pathway in rat articular chondrocyte senescence was assessed. The results of the current study demonstrated that IGF-1 promoted cellular senescence in rat articular chondrocytes via activation of SA-ß-gal and the upregulation of p53 and p21 mRNA and protein levels. IGF-1 enhanced Akt phosphorylation and treatment with Akt inhibitor, MK-2206, significantly suppressed the induction of these markers. Overall, the results indicated the involvement of IGF-1 and Akt in senescence exhibited by rat articular chondrocytes.

Functional MRI of the mouse olfactory system.

Although olfactory dysfunction is an early warning sign of Alzheimer's and Parkinson's diseases, and is commonly present in a range of other neurodegenerative disorders, the mechanisms for its pathogenesis are not yet clear. Since fMRI allows the mapping of spatial and temporal patterns of activity in multiple brain regions simultaneously, it serves as a powerful tool to study olfactory dysfunction in animal models of neurodegenerative diseases. Nonetheless, there have been no reports to date of mapping odor-induced activation patterns beyond the olfactory bulb to the extended networks of olfactory and limbic archicortex, likely due to the small size of the mouse brain. Therefore, using an 11.7 T magnet and a blood volume-weighted fMRI technique, we mapped the functional neuroanatomy of the mouse olfactory system. Consistent with reports on imaging of the much larger human brain, we mapped activity in regions of the olfactory bulb, as well as olfactory and limbic archicortex. By using two distinct odorants, we further demonstrated odorant-specific activation patterns. Our work thus provides a methodological framework for fMRI studies of olfactory dysfunction in mouse models of neurodegeneration.

Ultrasound-assisted liquid-liquid spray extraction for the determination of multi-class trace organic compounds in high-volume water samples.

In order to extract trace organic compounds (TrOCs) from large volumes of water (over 10 L), an ultrasound-assisted liquid-liquid spray extraction (UA-LLSE) technique is proposed. The UA-LLSE integrates liquid-liquid extraction, spray atomisation and ultrasonication in a single step. Under an acoustic field, a water sample is continuously spray injected into an extracting organic solvent to generate numerous water microdroplets in the organic phase. As a result, the extraction time and efficiency are significantly improved through increasing the interactive surface area, collision probability and mass transfer between two liquid phases. Other major parameters affecting the extraction efficiency such as nozzle type, spray angle, flow rate, nozzle position, ultrasonication energy, and extraction cycle were optimised. This newly developed technique has been applied to determine the trace organic compounds in real-world environmental matrices, and the results were compared with the results of the conventional liquid-liquid extraction method. For the analysis of high-volume water samples, UA-LLSE is a simple, inexpensive, time-saving (20 min for 10 L of water sample) and environmentally friendly method (reduction in solvent usage), with high extraction efficiency (over 90% average recoveries) and excellent precision (lower than 7% relative standard deviation, RSD). Most importantly, it is an ideal on-site pre-treatment technique for the in situ extraction of trace organic compounds in high-volume water matrices.

Multimodal MRI Evaluation of the MitoPark Mouse Model of Parkinson's Disease.

The MitoPark mouse, a relatively new genetic model of Parkinson's disease (PD), has a dopaminergic neuron-specific knock-out that inactivates the mitochondrial transcription factor A (Tfam), a protein essential for mitochondrial DNA expression and maintenance. This study used multimodal MRI to characterize the neuroanatomical correlates of PD-related deficits in MitoPark mice, along with functional behavioral tests. Compared with age-matched wild-type animals, MitoPark mice at 30 weeks showed: i) reduced whole-brain volume and increased ventricular volume, indicative of brain atrophy, ii) reduced transverse relaxation time (T2*) of the substantia nigra and striatum, suggestive of abnormal iron accumulation, iii) reduced apparent diffusion coefficient in the substantia nigra, suggestive of neuronal loss, iv) reduced fractional anisotropy in the corpus callosum and substantia nigra, indicative of white-matter damages, v) cerebral blood flow was not significantly affected, and vi) reduced motor activity in open-field tests, reduced memory in novel object recognition tests, as well as decreased mobility in tail suspension tests, an indication of depression. In sum, MitoPark mice recapitulate changes in many MRI parameters reported in PD patients. Multimodal MRI may prove useful for evaluating neuroanatomical correlates of PD pathophysiology in MitoPark mice, and for longitudinally monitoring disease progression and therapeutic interventions for PD.

Targeted overexpression of endothelial nitric oxide synthase in endothelial cells improves cerebrovascular reactivity in Ins2Akita-type-1 diabetic mice.

Reduced bioavailability of nitric oxide due to impaired endothelial nitric oxide synthase (eNOS) activity is a leading cause of endothelial dysfunction in diabetes. Enhancing eNOS activity in diabetes is a potential therapeutic target. This study investigated basal cerebral blood flow and cerebrovascular reactivity in wild-type mice, diabetic mice (Ins2(Akita+/-)), nondiabetic eNOS-overexpressing mice (TgeNOS), and the cross of two transgenic mice (TgeNOS-Ins2(Akita+/-)) at six months of age. The cross was aimed at improving eNOS expression in diabetic mice. The major findings were: (i) Body weights of Ins2(Akita+/-) and TgeNOS-Ins2(Akita+/-) were significantly different from wild-type and TgeNOS mice. Blood pressure of TgeNOS mice was lower than wild-type. (ii) Basal cerebral blood flow of the TgeNOS group was significantly higher than cerebral blood flow of the other three groups. (iii) The cerebrovascular reactivity in the Ins2(Akita+/-) mice was significantly lower compared with wild-type, whereas that in the TgeNOS-Ins2(Akita+/-) was significantly higher compared with the Ins2(Akita+/-) and TgeNOS groups. Overexpression of eNOS rescued cerebrovascular dysfunction in diabetic animals, resulting in improved cerebrovascular reactivity. These results underscore the possible role of eNOS in vascular dysfunction in the brain of diabetic mice and support the notion that enhancing eNOS activity in diabetes is a potential therapeutic target.

Bis[3-(pyrazin-2-yl)-5-(pyridin-2-yl-κN)-1,2,4-triazol-1-ido-κN(1)]copper(II).

In the mononuclear title complex, [Cu(C(11)H(7)N(6))(2)], the Cu(II) atom lies on a crystallographic inversion centre and is coordinated by four N atoms from two bidentate chelate monoanionic 3-(pyrazin-2-yl)-5-(pyridin-2-yl-1,2,4-triazol-1-ido ligands, two from the triazolide rings [Cu-N = 1.969 (2) Å] and two from the pyridine rings [Cu-N = 2.027 (2) Å], giving a slightly distorted square-planar geometry.

[Pharmacokinetic evaluation of danshensu with in vivo microdialysis in freely moving rat's jugular vein].

OBJECTIVE: To investigate the pharmacokinetics of Danshensu with in vivo microdialysis in freely moving rat's jugular vein. METHOD: three days after a microdialysis probe introducer was implanted into the jugular vein, a microdialysis probe was introduced to the blood vessel, and began to sample following a single intravenous injection (40 mg x kg(-1)) or a single oral dose (40 mg x kg(-1)) of Danshensu. All the samples were analyzed with HPLC. The concentration of Danshensu in blood were calculated according to the recovery of microdialysis probe and the concentration in dialysates. Pharmacokinetic parameters were than calculated with the concentration-time curve. RESULT: For intravenous administration, t(1/2 zeta) = (69.62 +/- 33.42) min, AUC(0-infinity) = (3416.24 +/- 779.80) min x mg x L(-1), MRT(0-infinity) = (38.15 +/- 8.61) min, and for oral administration, Cmax = (7.42 +/- 3.08) mg x L(-1), tmax = (31.50 +/- 8.57) min, t(1/2 zeta) = (83.25 +/- 37.35) min, AUC(0-infinity) = (793.19 +/- 101.32) min x mg x L(-1), MRT(0-infinity) = (125.89 +/- 58.27) min. The oral bioavailability of Danshensu F = 22.56%. CONCLUSION: In vivo microdialysis in freely moving rat's jugular vein is a useful tool to obtain a complete set of free drug concentrations to determine reliable pharmacokinetic parameters.

Ice phase as an important factor on the seasonal variation of polycyclic aromatic hydrocarbons in the Tumen River, Northeastern of China.

BACKGROUND, AIM AND SCOPE: The climatic characteristic is a major parameter affecting on the distribution variation of organic pollutants such as polycyclic aromatic hydrocarbons (PAHs). The Tumen River is located in Northeastern of China. The winter era lasts for more than 5 months in a year, and the river water was frozen and covered by ice phase. Coal combustion is an essential heating source in the Tumen River Basin. The objective of this research is to study ice phase effect on the seasonal variation of PAHs in the Tumen River environment. MATERIALS AND METHODS: Samples were collected from 13 sites along the River in March, July, October, and December of 2008. In addition, the ice sample, under ice water and air particulate were also collected in winter. The samples were analyzed for 16 PAHs (naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, beazo[a]anthene, chrysene, beazo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, indeno(1,2,3-cd)pyrene, dibenz(a,h)anthracene, and benzo(ghi)perylene). The compounds were extracted from the water samples and solid samples using LLE and Soxhlet extraction technique, respectively, and it is determined by gas chromatography-mass spectrometry. RESULTS AND DISCUSSION: Among 16 PAHs, fluorene, phenanthrene, and pyrene were found to be present in high concentrations and at high detection frequencies. The total concentration of PAHs in the water, particulate, sediment and ice phase ranged from 35.1-1.05 x 10(3) ng L(-1), 25.4-817 ng L(-1), 117-562 ng g(-1)and 62.8-136 ng g(-1), respectively. The levels of PAHs were generally higher in spring than other seasons. The ice phase in winter acts like a major reservoir of the pollutants and it is major contributor on the seasonal variation of PAHs in Tumen River. The PAHs found in water, particulate, and sediment in the Tumen River were possibly derived from similar pollution sources a proposition based on the compositions and isomer ratios of PAHs. CONCLUSIONS: The distribution of PAHs was showed clear seasonal variation in the Tumen River environment, the ice phase and air pollution look like an important factor affecting on the seasonal variation. RECOMMENDATIONS AND PERSPECTIVES: The ice phase as an important factor affecting on the seasonal variation of PAHs in Tumen River environment. Further studies regarding the effects of air pollution on the river and the mechanisms of migration and transformation of them in the environment are currently being conducted in our laboratory.

Digital tomosynthesis parallel imaging computational analysis with shift and add and back projection reconstruction algorithms.

Digital tomosynthesis is a novel technology that has been developed for various clinical applications. Parallel imaging configuration is utilised in a few tomosynthesis imaging areas such as digital chest tomosynthesis. Recently, parallel imaging configuration for breast tomosynthesis began to appear too. In this paper, we present the investigation on computational analysis of impulse response characterisation as the start point of our important research efforts to optimise the parallel imaging configurations. Results suggest that impulse response computational analysis is an effective method to compare and optimise imaging configurations.