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1.
World Neurosurg ; 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31589981

RESUMO

BACKGROUND: Choice of treatment strategy, design of screw trajectory and protection of vertebral artery are still challenging problems in complex CVJ anomaly surgeries. OBJECTIVE: To evaluate the usefulness of three-dimensional (3D) printed models as an aid for the treatment of complex CVJ anomalies. METHODS: Three-dimensional printed models were fabricated for 21 patients with complex CVJ anomalies, including vertebral artery anomaly, thin C2 pedicle, vertical atlantoaxial facet joint or rotational dislocation combined with atlantoaxial dislocation and basilar invagination. Preoperative planning, surgical simulation and intraoperative reference were achieved using the 3D model during the surgical treatment. The usefulness of 3D printed models, as well as postoperative clinical and radiological outcomes were assessed. RESULTS: Direct posterior reduction and atlantoaxial fixation were achieved in 19 patients. Transoral odontoidectomy followed by posterior fixation was implemented for 2 patients with vertical facet joint and rotational dislocation. All screws were safely inserted with no complication happened, and 90% patients achieved >60% reduction of both horizonal and vertical dislocation. Clinical symptoms improved in all patients, with the averaged JOA scores increased from 11.14 to 14.43 (P<0.01). CONCLUSION: The patient-specific 3D printed model would be an effective tool for evaluation of the reducibility of the AAD and BI, decision-making in choosing the optimal surgical approach and way of fixation, and precise placement of the screw while protecting the VA and spinal cord. The risk of neurovascular injury was minimized and encouraging outcomes were achieved with the aid of this technique.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31584103

RESUMO

BACKGROUND: For patients with odontoid process protrusion and basilar invagination, posterior screw-rod fixation can usually achieve satisfactory horizontal reduction, but in some cases satisfactory reduction in the vertical direction cannot be achieved at the same time. OBJECTIVE: To propose a method for calculation of the theoretical maximum vertical reduction possible in individual patients. METHODS: The computed tomography imaging data of patients with occipitalization and basilar invagination who were treated at our institute between January 2013 and June 2016 were retrospectively analyzed. The direction of odontoid reduction was decided by the inclination of the lateral joint. The atlanto-dental distance was assumed to be the maximum possible reduction in the horizontal direction. The maximum vertical reduction possible was calculated based on these values. RESULTS: A total of 82 patients (34 males and 48 females) were included. The theoretical vertical reduction value was 4.2 ± 3.0 mm, which was significantly smaller than that of the dental protrusion (14.5 ± 3.8 mm, P = .000). Analysis of follow-up data (29 cases) showed that, the difference between the theoretical vertical reduction value H (4.7 ± 3.5 mm) and the actual vertical reduction value Ha (5.6 ± 3.5 mm) was not significant (P = .139). CONCLUSION: The theoretical calculation method we proposed can well predict the actual degree of vertical reduction. The theoretical vertical reduction value is significantly lower than the odontoid protrusion value, indicating that satisfactory reduction in the vertical direction is difficult with a posterior approach alone.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31633336

RESUMO

Hydrogels with shapes that can be adapted to environment have attracted great attention from both academic and industrial community. We report herein a new and robust strategy to reprogram the light-induced shape transformation of thermo-responsive composite hydrogel sheet with erasable and rewritable patterns of iron oxide nanoparticles as photothermal agents. Numerous distinct and reversible shape transformations are achieved from a single hydrogel sheet by repeatably writing in the sheet with different nanoparticle patterns. The shape transformations were verified by finite element modeling. The present strategy is simple, fast and efficient in reprogramming shape change of thermo-responsive hydrogel material. The composite hydrogel sheet may find applications in soft robotics, tissue engineering and controlled release.

4.
J Am Chem Soc ; 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31647658

RESUMO

The construction of two-dimensional (2D) layered compounds for nanofluidic ion transport has recently attracted increasing interest due to the facile fabrication, tunable channel size, and high flux of these materials. Here we design a nacre-mimetic graphite-based nanofluidic structure in which the nanometer-thick graphite flakes are wrapped by negatively charged nanofibrillated cellulose (NFC) fibers to form multiple 2D confined spacings as nanochannels for rapid cation transport. At the same time, the graphite-NFC structure exhibits an ultralow electrical conductivity (σe ≤ 10-9 S/cm), even when the graphite concentration is up to 50 wt %, well above the percolation threshold (∼1 wt %). By tuning the hydration degree of graphite-NFC composites, the surface-charge-governed ion transport in the confined ∼1 nm spacings exhibits nearly 12 times higher ionic conductivity (1 × 10-3 S/cm) than that of a fully swollen structure (∼1.5 nm, 8.5 × 10-5 S/cm) at salt concentrations up to 0.1 M. The resulting charge selective conductor shows intriguing features of both high ionic conductivity and low electrical conductivity. Moreover, the inherent stability of the graphite and NFC components contributes to the strong functionality of the nanofluidic ion conductors in both acidic and basic environments. Our work demonstrates this 1D-2D material hybrid system as a suitable platform to study nanofluidic ion transport and provides a promising strategy to decouple ionic and electronic pathways, which is attractive for applications in new nanofluidic device designs.

5.
Chemistry ; 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31553090

RESUMO

Hollow ZSM-5 zeolites whose size are below 1 micrometer can be produced by desilication of crystals with aluminum-zoning. The parent crystals have a core-shell structure: the core part has nearly no aluminum, whereas the aluminum content in the shell increases when extending to exterior surface. Transmission electron microscopy confirms the preservation of the crystalline shell after base leaching, but cannot identify its subtle change. An increase of the Si/Al ratio of the surface is detected upon leaching the parent material to form the hollow zeolite, using ambient pressure x-ray photoelectron spectroscopy and infrared spectroscopy of substituted alkylpyridines. 27 Al MAS NMR exhibits that base leaching results in a reduced percentage of distorted tetrahedrally-coordinated aluminum. The reprecipitation of dissolved species occurs and tetrahedrally-coordinated tin atoms can thus be introduced to the shell framework. Overall, the formation of hollow ZSM-5 zeolites by desilication involves not only the removal of silicon-rich core, but also a reduced percentage of exterior aluminum-related acid sites, which should be considered while using hollow zeolites in acid-catalyzed reactions.

6.
J Bone Miner Metab ; 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31493249

RESUMO

The development of postmenopausal osteoporosis is thought to be closely related to oxidative stress. Mn(III)tetrakis (4-benzoic acid) porphyrin (MnTBAP), a novel superoxide dismutase (SOD) mimetic, could protect osteoblasts from cytotoxicity and dysfunction caused by oxidative stress. However, it is still unclear whether MnTBAP has effect on the development of postmenopausal osteoporosis. Here, we demonstrated that MnTBAP can inhibit bone mass loss and bone microarchitecture alteration, and increase the number of osteoblasts while reducing osteoclasts number, as well as improve the BMP-2 expression level in ovariectomized rat model. Additionally, MnTBAP can also prevent oxidative stress status up-regulation induced by ovariotomy and hydrogen peroxide (H2O2). Furthermore, MnTBAP reduced the effect of oxidative stress on osteoblasts differentiation and increased BMP-2 expression levels with a dose-dependent manner, via reducing the levels of mitochondrial oxidative stress in osteoblasts. Taken together, our findings provide new insights that MnTBAP inhibits bone loss in ovariectomized rats by reducing mitochondrial oxidative stress in osteoblasts, and maybe a potential drug in postmenopausal osteoporosis therapy.

7.
Curr Biol ; 29(16): 2597-2603.e4, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31378606

RESUMO

Sessile organisms with thermally sensitive developmental trajectories are at high risk from climate change. For example, oviparous reptiles with temperature-dependent sex determination (TSD) may experience strong (potentially disastrous) shifts in offspring sex ratio if reproducing females are unable to predict incubation conditions at the time of oviposition. How then have TSD reptile taxa persisted over previous periods of extreme climatic conditions? An ability of embryos to move within the egg to select optimal thermal regimes could buffer ambient extremes, but the feasibility of behavioral thermoregulation by embryos has come under strong challenge. To test this idea, we measured thermal gradients within eggs in semi-natural nests of a freshwater turtle species with TSD, manipulated embryonic thermoregulatory ability, and modeled the effects of embryonic thermoregulation on offspring sex ratios. Behavioral thermoregulation by embryos accelerated development and influenced offspring sex ratio, expanding the range of ambient conditions under which nests produce equal numbers of male and female offspring. Model projections suggest that sex ratio shifts induced by global warming will be buffered by the ability of embryos to influence their sexual destiny via behavioral thermoregulation.

8.
Nat Nanotechnol ; 14(9): 851-857, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31406363

RESUMO

The stability of single-atom catalysts is critical for their practical applications. Although a high temperature can promote the bond formation between metal atoms and the substrate with an enhanced stability, it often causes atom agglomeration and is incompatible with many temperature-sensitive substrates. Here, we report using controllable high-temperature shockwaves to synthesize and stabilize single atoms at very high temperatures (1,500-2,000 K), achieved by a periodic on-off heating that features a short on state (55 ms) and a ten-times longer off state. The high temperature provides the activation energy for atom dispersion by forming thermodynamically favourable metal-defect bonds and the off-state critically ensures the overall stability, especially for the substrate. The resultant high-temperature single atoms exhibit a superior thermal stability as durable catalysts. The reported shockwave method is facile, ultrafast and universal (for example, Pt, Ru and Co single atoms, and carbon, C3N4 and TiO2 substrates), which opens a general route for single-atom manufacturing that is conventionally challenging.

9.
Adv Mater ; 31(35): e1902930, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31267581

RESUMO

Biological materials with hierarchical architectures (e.g., a macroscopic hollow structure and a microscopic cellular structure) offer unique inspiration for designing and manufacturing advanced biomimetic materials with outstanding mechanical performance and low density. Most conventional biomimetic materials only benefit from bioinspired architecture at a single length scale (e.g., microscopic material structure), which largely limits the mechanical performance of the resulting materials. There exists great potential to maxime the mechanical performance of biomimetic materials by leveraging a bioinspired hierarchical structure. An ink-based three-dimensional (3D) printing strategy to manufacture an ultralight biomimetic hierarchical graphene material (BHGMs) with exceptionally high stiffness and resilience is demonstrated. By simultaneously engineering 3D-printed macroscopic hollow structures and constructing an ice-crystal-induced cellular microstructure, BHGMs can achieve ultrahigh elasticity and stability at compressive strains up to 95%. Multiscale finite element analyses indicate that the hierarchical structures of BHGMs effectively reduce the macroscopic strain and transform the microscopic compressive deformation into the rotation and bending of the interconnected graphene flakes. This 3D printing strategy demonstrates the great potential that exists for the assembly of other functional materials into hierarchical cellular structures for various applications where high stiffness and resilience at low density are simultaneously required.

10.
Front Immunol ; 10: 1550, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354713

RESUMO

Vertical transmission of the intracellular parasite Toxoplasma gondii (T. gondii) can lead to devastating consequences during gestation. Tim-3, a negative immune regulator, is constitutively expressed on decidual macrophages, but its specific role during T. gondii infection has not yet been explored. In the present study, we discovered that Tim-3 plays an important role in the abnormal pregnancy due to T. gondii infection using Tim-3-/- pregnant mice and anti-Tim-3 neutralizing antibody treated human decidual macrophages. The results showed that abnormal pregnancy outcomes were more prevalent in Tim-3-/- infected pregnant mice than in wild-type infected pregnant mice. Tim-3 expression in decidual macrophages was significantly down-regulated after T. gondii infection both in vitro and in vivo. Tim-3 down-regulation by T.gondii infection could strengthen M1 activation and weaken M2 tolerance by changing the M1 and M2 membrane molecule expression, arginine metabolic enzymes synthesis, and cytokine secretion profiles of decidual macrophages. Moreover, Tim-3 down-regulation by T.gondii infection led to PI3K-AKT phosphorylation inhibition, downstream transcription factor C/EBPß expression, and SOCS1 activation, which resulted in enzymes synthesis regulation and cytokines secretion. Our study demonstrates that Tim-3 plays an indispensable role in the adverse pregnancy outcomes caused by T. gondii infection.

11.
Rev Sci Instrum ; 90(6): 065113, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31254981

RESUMO

Small-thrust liquid-pulsed thrusters can achieve higher efficiency and more accurate control when operating in pulsed mode. However, the pulsed characteristic makes it challenging to measure the thrust. This paper describes a thrust stand for directly measuring the pulsed thrust from small-thrust liquid-pulsed thrusters. The proposed stand is based on a unique piezoelectric dynamometer on which the thruster is mounted through a connecting frame. A thrust experiment is conducted by applying a trapezoidal pulsed force, similar to the thrust generated by small-thrust liquid-pulsed thrusters, to the thrust stand. The experimental results show that the thrust stand can quickly trace the input trapezoidal force signal, although its output waveform exhibits obvious oscillations. Based on the experimental frequency response data, a thrust stand transfer function model is constructed, and this model is used to analyze the dynamic response performance of the thrust stand. The step response and trapezoidal pulse response of the thrust stand are obtained, and the influence of the damping ratio on the dynamic performance of the thrust stand is analyzed. A damping compensation transfer function is established to improve the dynamic measurement performance of the thrust stand. Compensated results are obtained by using the raw output from the thrust stand as the input to the damping compensation transfer function. The damping compensation method does not change the natural frequencies of the thrust stand, does not need any additional filtering process, effectively eliminates the waveform oscillations of the thrust stand output, and ensures good consistency between the input and output signals.

12.
Nat Commun ; 10(1): 3316, 2019 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-31346178

RESUMO

3D electron crystallography has recently attracted much attention due to its complementarity to X-ray crystallography in determining the structure of compounds from submicrometre sized crystals. A big obstacle lies in obtaining complete data, required for accurate structure determination. Many crystals have a preferred orientation on conventional, flat sample supports. This systematically shades some part of the sample and prevents the collection of complete data, even when several data sets are combined. We introduce two types of three-dimensional sample supports that enable the collection of complete data sets. In the first approach the carbon layer forms coils on the sample support. The second approach is based on chaotic nylon fibres. Both types of grids disrupt the preferred orientation as we demonstrate with a well suited crystal type of MFI-type zeolites. The easy-to-obtain three-dimensional sample supports have different features, ensuring a broad spectrum of applications for these 3D support grids.

13.
Neurochem Int ; 129: 104496, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31247243

RESUMO

In this study, the effects of chrysin on cerebral ischemia by establishing middle cerebral artery occlusion (MCAO) in rat were investigated. In vivo experiments, the rats were orally administrated with clopidogrel or chrysin once daily for 7 days before the experimental of ischemia and the rats were divided into 5 groups: the sham group, the I/R group, I/R + clopidogrel group, I/R + chrysin (10 mg/kg), I/R + chrysin (20 mg/kg) group. Chrysin significantly ameliorated the I/R rats, evaluated by TTC staining, determination of brain wet to dry weight ratio and neurological deficits. Moreover, in serum and brain tissues of the I/R rats, chrysin also could effectively suppress the release of inflammatory cytokines, including levels of interleukin-6 (IL-6), interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α). In addition, chrysin could improve the SOD activity in the I/R rats. Mechanically, chrysin could activate the PI3K/Akt/mTOR pathway, inhibited inflammation and apoptosis. In oxygen-glucose deprivation and recovery (OGD/R)-induced SH-SY5Y cells in vitro. Chrysin markedly decreased the levels of TNF-α, IL-6 and IL-1ß in supernatant of OGD/R-induced SH-SY5Y cells via activating PI3K/Akt/mTOR pathway. In conclusion, our study demonstrated that chrysin might be a potential therapeutic agent for cerebral ischemia.

14.
World Neurosurg ; 130: e505-e512, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31254707

RESUMO

INTRODUCTION: The occipitalization of the atlas (OA) is always associated with multiplanar dislocation and olisthy of the C1 over C2 facets, which may change the anatomical relationship between the internal carotid artery (ICA) and the atlas. The purpose of this current study is to identify the location of the ICA relative to the anterior aspect of the atlas in patients with OA and define the clinical implications for screw placement. METHODS: We retrospectively reviewed the computed tomography angiography data of 86 patients with OA and 86 control subjects. Several parameters were also measured to quantitatively evaluate the mutual relationship. RESULTS: In the OA group, 25.6% of ICAs were located in area 3 and 74.4% in area 2, whereas the percentages were 57.4% and 42.6%, respectively, in the control group. There were 73 (42.4%) ICAs in which the shortest distance between the dorsal surface of the ICA and the ventral cortex of the atlas was less than 4 mm in the OA group and only 50 (29.1%) in the control group. The ideal angulation of C1 screw trajectory was about 5 degrees more medial in the OA group than that in the control group (P < 0.01). CONCLUSIONS: The risk of ICA injury is much higher in OA patients than in non-OA patients during the C1 screw placement. A mean medial angulation about 20 degrees will permit a long and safe screw purchase, but should be individualized. We recommend careful preoperative computed tomography angiography evaluation in all patients before surgery.

15.
Antioxid Redox Signal ; 31(11): 771-785, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31250660

RESUMO

Aims: Severe acute pancreatitis (AP) is a serious condition without specific treatment. Mitochondrial dysfunction plays a crucial role in the pathogenesis of AP. Irisin, a novel exercise-induced hormone, contributes to many health benefits of physical activity. We and others have shown that irisin protects against ischemia reperfusion-induced organ injury by alleviating mitochondrial damage. However, the role of irisin in AP has not been evaluated. The purpose of this study was to investigate the role of serum irisin levels in patients with AP and the effect of irisin administration in experimental AP. Results: Serum irisin levels were decreased in AP patients, and low serum irisin levels were associated with worse outcomes in these patients. Treatment with exogenous irisin increased survival and mitigated pancreatic injury in experimental AP. The protective effects of irisin in AP were associated with improvement in mitochondrial function and reduction in ER stress. Moreover, irisin upregulated UCP2 expression in the pancreas, and administration of genipin, a specific UCP2 antagonist, abolished irisin's beneficial effects in L-arginine-induced AP. Innovation and Conclusion: Low serum irisin was associated with poor outcomes in AP patients, and irisin administration protected against experimental AP by restoring mitochondrial function via activation of UCP2. Restoration of mitochondrial function by irisin may offer therapeutic potential for patients with AP. Antioxid. Redox Signal. 31, 771-785.

16.
Cell Death Dis ; 10(6): 428, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31160555

RESUMO

Triple-negative breast cancer (TNBC), defined by the lack of expression of estrogen, progesterone, and ERBB2 receptors, has the worst prognosis of all breast cancers. It is difficult to treat owing to a lack of effective molecular targets. Here, we report that the growth of TNBC cells is exceptionally dependent on PICH, a DNA-dependent ATPase. Clinical samples analysis showed that PICH is highly expressed in TNBC compared to other breast cancer subtypes. Importantly, its high expression correlates with higher risk of distal metastasis and worse clinical outcomes. Further analysis revealed that PICH depletion selectively impairs the proliferation of TNBC cells, but not that of luminal breast cancer cells, in vitro and in vivo. In addition, knockdown of PICH in TNBC cells induces the formation of chromatin bridges and lagging chromosomes in anaphase, frequently resulting in micronucleation or binucleation, finally leading to mitotic catastrophe and apoptosis. Collectively, our findings show the dependency of TNBC cells on PICH for faithful chromosome segregation and the clinical potential of PICH inhibition to improve treatment of patients with high-risk TNBC.

17.
Spine J ; 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31254651

RESUMO

BACKGROUND CONTEXT: The mechanical strength provided by internal fixation is crucial for maintaining reduction and facilitating bony fusion. Though satisfactory results with the C1-C2 technique have been acquired in most clinical reports, the related problems of fusion delay and pseudarthrosis still exist. To increase the chance of bony fusion, a transverse connector (TC) is frequently used to augment torsional stiffness of thoracolumbar screw/rod constructs. Nevertheless, the clinical implication of TC in the management of atlantoaxial dislocation (AAD) and basilar invagination (BI) remains largely unknown. PURPOSE: To evaluate the effects of TC application on C1-C2 screw-rod constructs based on consecutive adult patients with AAD and BI in a single institution over a 10-year period. STUDY DESIGN: A retrospective study. PATIENT SAMPLE: Patients with AAD and BI, who were treated with posterior C1-C2 screw-rod technique with or without TC usage from June 2007 to June 2017 at a single institution. OUTCOME MEASURES: The radiological measurements included the anterior atlantodental interval (AADI), posterior atlantodental interval (PADI), height of odontoid process above Chamberlain line, and cervicomedullary angle (CMA). Patients' neurologic status was evaluated with the Japanese Orthopaedic Association (JOA) score. Fusion status was evaluated at different follow-up periods. METHODS: We compared the difference of clinical, radiological, and surgical outcomes between the TC and NTC groups postoperatively. RESULTS: In total, there were 149 consecutive patients in the TC group and 168 patients in the NTC group. On average, 1.2 TCs per patient were used in the TC group. No significant differences were identified for operative time and blood loss between groups. There was also no statistical difference in the radiological measurements of AADI, PADI, Chamberlain line, and CMA between the TC and NTC groups preoperatively and postoperatively. A significantly higher JOA score was obtained in the TC group than that in the NTC group postoperatively. The fusion rates were higher in the TC group than those in the NCT group at the early stage postoperatively (3 and 6 months; p<.01). CONCLUSIONS: Use of TCs seems to improve bony fusion and neurologic outcomes in the treatment of AAD and BI with C1-C2 screw-rod technique.

18.
BMC Cardiovasc Disord ; 19(1): 100, 2019 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-31035937

RESUMO

BACKGROUND: Persistent left superior vena cava (PLSVC) is a rare congenital vascular anomaly. Permanent pacemaker implantation (PPI) in patients with PLSVC can be challenging because of the venous anomalies. We reported a case series of patients with PLSVC who underwent PPI with double active fixation leads. METHODS: From January 2012 to July 2016, 9 patients (three male and six females, mean age 68 ± 11 years) with PLSVC who received a dual-chamber pacemaker with double active fixation leads were enrolled retrospectively in this observational study. The indications for pacemaker implantation were symptomatic third-degree atrioventricular block in one and sick sinus syndrome in eight patients. RESULTS: PPI were implanted successfully in all 9 patients. Successful positioning of the ventricular leads at the right ventricular outflow tract (RVOT) septum with a "C" shaped stylet was achieved in 7 patients (77.8%). In the remaining two cases, the ventricular leads were placed in the right ventricular apex and the inferior free wall of the sub-tricuspid annulus. The atrial leads were placed at the lateral wall of the right atrium in all patients. Procedure time and fluoroscopy time were 85.3 ± 11.3 min and 4.5 ± 1.1 min respectively. During a mean follow-up of 4 years, no complications were observed and pacing parameters did not change significantly. CONCLUSION: PPI through PLSVC may be technically feasible, safe, and effective. Double active fixation leads may be standard for patients with PLSVC and most of the ventricular leads could be placed at the RVOT septum.

19.
Molecules ; 24(10)2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31121832

RESUMO

Medicarpin is a bioactive pterocarpan that has been attracting increasing attention in recent years. However, its metabolic fate in vivo is still unknown. To clarify its metabolism and the distribution of its metabolites in rats after oral administration, the HPLC-ESI-IT-TOF-MSn technique was used. A total of 165 new metabolites (13 phase I and 152 phase II metabolites) were tentatively identified, and 104, 29, 38, 41, 74, 28, 24, 15, 42, 8, 10, 3, and 17 metabolites were identified in urine, feces, plasma, the colon, intestine, stomach, liver, spleen, kidney, lung, heart, brain, and thymus, respectively. Metabolic reactions included demethylation, hydrogenation, hydroxylation, glucuronidation, sulfation, methylation, glycosylation, and vitamin C conjugation. M1 (medicarpin glucuronide), M5 (vestitol-1'-O-glucuronide) were distributed to 10 organs, and M1 was the most abundant metabolite in seven organs. Moreover, we found that isomerization of medicarpin must occur in vivo. At least 93 metabolites were regarded as potential new compounds by retrieving information from the Scifinder database. This is the first detailed report on the metabolism of ptercarpans in animals, which will help to deepen the understanding of the metabolism characteristics of medicarpin in vivo and provide a solid basis for further studies on the metabolism of other pterocarpans in animals.

20.
Math Biosci Eng ; 16(4): 2492-2513, 2019 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-31137224

RESUMO

This paper aims to investigate human hands-and-knees crawling movement from the aspect of synchronous (SYN) and time-varying (TV) muscle synergy analysis. Nine healthy children and 11 children with cerebral palsy were recruited. During hands-and-knees crawling, surface electromyography (sEMG) signals from 12 main muscles of upper limbs and trunk were recorded, and muscle synergies were extracted based on TV synergy and SYN synergy theories. From the perspectives of repeatability, symmetry and similarity, the abilities of these two types of synergies to characterize crawling movement and to distinguish normal and abnormal crawling were explored. We found that: First, SYN synergy is better than TV synergy in depicting the body symmetry during crawling movement. However, TV synergy is more suitable than SYN synergy for distinguishing normal and abnormal crawling from the perspective of symmetry. Second, the abilities of SYN synergy and TV synergy in depicting the crawling repeatability are not comparable, and both have the potential to depict the crawling abnormality from the perspective of repeatability. Third, from the angle of inter-subject similarity, SYN synergy has the potential to describe the abnormal crawling pattern. However, the large individual differences suggest that TV synergy is a poor choice. This study provides a new way to analyze crawling movement from the perspective of neuromuscular control, and the research findings are meaningful for clinical assessment of abnormal crawling.

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