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1.
World Neurosurg ; 2020 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-32353541

RESUMO

BACKGROUND: Factors associated with visual outcomes after transcranial surgery for large-to-giant pituitary adenomas have not been fully elucidated. METHODS: We recruited 37 patients with large-to-giant pituitary adenomas between January 2014 and December 2016 and assessed their tumor characteristics and surgical outcomes. Visual acuity and visual field were evaluated by Visual impairment score (VIS) before and 3-6 months after transcranial surgery. Multivariable logistic regression analysis was applied to reveal the factors associated with visual outcomes after surgery. RESULTS: The severity levels of visual impairment before surgery were mild, moderate, severe, and complete in 24.3% (9/37), 24.3% (9/37), 35.1% (13/37), and 16.2% (6/37), respectively. After surgery, the visual function was improved, stabilized, and worsened in 43.2% (16/37), 43.2% (16/37), and 13.5% (5/37) of patients, respectively. Multivariable logistic regression analysis showed that subarachnoid space invasion was the only independent prognostic factor adversely influencing the postoperative visual outcomes. Patients with subarachnoid space invasion had a higher possibility of visual deterioration (36.4% vs. 3.8%, p = 0.021) after transcranial surgery, compared with those without subarachnoid space invasion. CONCLUSIONS: Visual compromise is still an unignorable complication during transcranial surgery for large-to-giant pituitary adenomas. Subarachnoid space invasion indicated by preoperative MRI was an independent negative predictor for visual outcomes after surgery.

2.
J Nanosci Nanotechnol ; 20(9): 5629-5635, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32331148

RESUMO

The practical application of lithium-sulfur batteries (LSBs) has been impeded by several chronic problems related to the insulating nature of sulfur and lithium sulfide, in addition to the dissolution and diffusion of lithium polysulfides. In view of these problems, a large variety of carbonaceous materials have been employed to enhance the electronic conductivity of the cathode and/or sequester lithium polysulfides within conductive matrixes. Although they may exhibit impressive electrochemical performance, the fabrication of most carbon materials involves costly precursors and complicated procedures. Waste paper-the main constituent of municipal waste-is composed of carbohydrates, and can be an ideal precursor for carbon materials. Herein, carbon microfiber meshes (CMFMs) obtained by the pyrolysis of common filter paper in argon (A-CMFM) or ammonia (N-CMFM) were used to form sulfur cathodes. Compared with LSBs based on A-CMFM, those based on N-CMFM demonstrated higher specific capacity and better rate capability, with a capacity of 650 mA h g-1 at 0.2 C and 550 mA h g-1 at 0.5 C. This was owing to the strong immobilization of lithium polysulfides resulting from the heteroatom doping and hydrophilicity of N-CMFM. The results indicate that cellulose paper-derived carbon is a promising candidate for application in high-performance LSBs.

3.
Kidney Blood Press Res ; : 1-13, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32209792

RESUMO

BACKGROUND: Despite the high mortality of cardiovascular disease (CVD) in diabetic patients with renal injury, few studies have compared cardiovascular characteristics and outcomes between patients with diabetic nephropathy (DN) and non-diabetic renal disease (NDRD). METHODS: A total of 326 type 2 diabetes mellitus patients with renal biopsy were assigned to DN and NDRD groups. Echocardiography and Doppler ultrasound were performed to evaluate left ventricular hypertrophy (LVH) and peripheral atherosclerosis disease (PAD). Renal and cardiovascular survival rates were compared between the DN and NDRD groups by Kaplan-Meier analysis. Risk factors for renal and cardiovascular events in DN patients were identified by a Cox proportional hazards model. RESULTS: In total, 179 patients entered the DN group (54.9%) and 147 made up the NDRD group (45.1%). The presence of diabetic retinopathy, family history of diabetes, and dependence on insulin therapy were associated with the presence of DN. DN patients had more CVD with more severe LVH and PAD. Poorer renal (log-rank χ2 = 26.534, p < 0.001) and cardiovascular (log-rank χ2 = 16.257, p < 0.001) prognoses were seen in the DN group. DR (HR 1.539, 95% CI 1.332-1.842), eGFR (HR 0.943, 95% CI 0.919-0.961), and 24-h proteinuria (HR 1.211, 95% CI 1.132-1.387) were identified as risk factors for renal endpoints. Age (HR 1.672, 95% CI 1.487-1.821), HbA1C (HR 1.398, 95% CI 1.197-1.876), and 24-h proteinuria (HR 1.453, 95% CI 1.289-1.672) were associated with cardiovascular endpoints. CONCLUSION: Patients with DN had more severe CVD along with poorer renal and cardiovascular prognoses than those with NDRD.

4.
Mar Pollut Bull ; 150: 110730, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31767204

RESUMO

Iron is recognized as an efficient method to alleviate sulfide stress. This study tested the response of Zostera marina plants to different levels of sedimentary sulfides (100.0-818.7 µmol L-1) and iron inputs (590.0-825.3 µg L-1) in a field experiment performed over an eighty-day period. We measured plant responses in terms of shoot density and plant morphology and productivity. The relationship between the propagation effort (PE, in %) and sulfide content (S, in µmol L-1) was expressed as: PE = -14.01 × ln (S) + 86.86 (R2 = 0.99, p < .01), which indicates that the toxic limit of the pore-water sulfide concentration for the survival of eelgrass is 493 µmol L-1. The addition of iron can reduce the toxicity of sulfides to eelgrass beds, resulting in an increase in plant density and productivity, and can even reverse the decline of eelgrass beds exposed to high sulfide concentrations.

5.
ACS Chem Neurosci ; 11(2): 133-145, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31815422

RESUMO

Metabotropic glutamate receptors of class C GPCRs exist as constitutive dimers, which play important roles in activating excitatory synapses of the central nervous system. However, the activation mechanism induced by agonists has not been clarified in experiments. To address the problem, we used microsecond all-atom molecular dynamics (MD) simulation couple with protein structure network (PSN) to explore the glutamate-induced activation for the mGluR1 homodimer. The results indicate that glutamate binding stabilizes not only the closure of Venus flytrap domains but also the polar interaction of LB2-LB2, in turn keeping the extracelluar domain in the active state. The activation of the extracelluar domain drives transmembrane domains (TMDs) of the two protomers closer and induces asymmetric activation for the TMD domains of the two protomers. One protomer with lower binding affinity to the agonist is activated, while the other protomer with higher binding energy is still in the inactive state. The PSN analysis identifies the allosteric regulation pathway from the ligand-binding pocket in the extracellular domain to the G-protein binding site in the intracellular TMD region and further reveals that the asymmetric activation is attributed to a combination of trans-pathway and cis-pathway regulations from two glumatates, rather than a single activation pathway. These observations could provide valuable molecular information for understanding of the structure and the implications in drug efficacy for the class C GPCR dimers.

6.
Clin Cancer Res ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31732519

RESUMO

PURPOSE: Immunogenicity derived from the murine scFv, a major molecular compomemt of chimeric antigen receptors (CARs), may limit the persistence of CAR T cells, resulting in tumor relapse of patients in complete remission (CR). In this study, we developed a humanized anti-CD19 scFv CAR-T (hCAR-T) to treat patients with relapsed/refractory acute lymphoblastic leukemia (r/r ALL). EXPERIMENTAL DESIGN: In this one-arm, open-labeled study, we infused the T cells modified with hCAR to patients with r/r ALL. Patients were evaluated with long-term follow-up for response and safety of the treatment. The study was registered at Clinicaltrials.gov (NCT02349698). RESULTS: Ten patients with r/r ALL were recruited for this study. All were response evaluable and all achieved CR; eight patients remained CR, and six were in CR for over 18 months without further treatment. A long-term persistence of hCAR T cells was observed in most of the patients. Among these patients, four of them with high tumor burden and rapidly progressive disease (median, 58%) experienced grade 3-4 cytokine release syndrome (CRS) and neurotoxicity. These severe CRSs were successfully controlled by tocilizumab, glucocorticoid, and plasma exchange. CONCLUSIONS: T cells expressing the humanized anti-CD19 scFv CARs exhibited sustained therapeutic efficacy in the treatment of r/r ALL. Low replase rate was associated with the long-term persistence of CAR T cells.

7.
Glob Chall ; 3(11): 1900043, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31692940

RESUMO

Nitrogen and sulfur co-doped graphene-like carbon (N,S-GLC) is successfully prepared in a one-step hydrothermal reaction of glucose with industrial dye wastewater followed by chemical activation. The nitrogen and sulfur are sourced entirely from the industrial wastewater. The process not only provides an alternative way of treating industry wastewater, but also offers a green route for recovering energy from the waste in the form of chemicals. The resultant N,S-GLC shows a good degree of graphitization, a high specific surface area (1734 m2 g-1), and moderate heteroatom doping (N: 2.1 at%, S: 0.7 at%). The N,S-GLC electrode displays high specific capacitance of 275 F g-1 at a current density of 0.5 A g-1 with a retention of 65.4% at 20 A g-1 in 6 m KOH. Moreover, the assembled symmetrical supercapacitor cell shows a capacitance of 38 F g-1 at a current density of 0.5 A g-1, which is equivalent to an energy density of 6.4 Wh kg-1 at a power density of 275.0 W kg-1. This approach provides an alternative and sustainable way of fabricating heteroatom-doped graphene-like carbon materials for use in high-performance supercapacitors.

8.
Adv Sci (Weinh) ; 6(18): 1900412, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31559125

RESUMO

The further practical applications of halide perovskite quantum dots (QDs) are blocked by problems of instability and nonradiative Auger recombination manifested as photoluminescence blinking. Here, single core/shell structured perovskite semiconductor QDs are successfully fabricated by capping CsPbBr3 QD core with CdS shell. It is demonstrated that CsPbBr3/CdS core/shell QDs exhibit ultrahigh chemical stability and nonblinking photoluminescence with high quantum yield due to the reduced electronic traps within the core/shell structure. Efficiency of amplified spontaneous emission exhibits obvious enhancement compared to that of pure CsPbBr3 QDs, originating from the mitigated competition between stimulated emission and suppressed nonradiative biexciton Auger recombination. Furthermore, low-threshold whispering-gallery-mode lasing with a high-quality factor is achieved by incorporating CsPbBr3/CdS QDs into microtubule resonators. Density functional theory (DFT)-based first-principles calculations are also performed to reveal the atomic interface structure, which supports the existence of CsPbBr3/CdS structure. An interesting feature of spatially separated charge density at CsPbBr3/CdS interface is found, which may greatly contribute to the suppressed Auger recombination. The results provide a practical approach to improve the stability and suppress the blinking of halide perovskite QDs, which may pave the way for future applications for various optoelectronic devices.

9.
PLoS One ; 14(9): e0222448, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31525217

RESUMO

China's transport sector is facing enormous challenges from soaring energy consumption and greenhouse gas (GHG) emissions. Transport electrification has been viewed as a major solution to transportation decarbonization, and electric vehicles (EVs) have attracted considerable attention from policymakers. This paper analyzes the effects of the introduction of EVs in China. A system dynamics model is developed and applied to assess the energy-saving and emission-reducing impacts of the projected penetration of EVs until the year 2030. Five types of scenarios of various EV penetration rates, electricity generation mixes, and the speed of technological improvement are discussed. Results confirm that reductions in transport GHG emissions and gasoline and diesel consumption by 3.0%-16.2%, 4.4%-16.1%, and 15.8%-34.3%, respectively, will be achieved by 2030 under China's projected EV penetration scenarios. Results also confirm that if EV penetration is accompanied by decarbonized electricity generation, that is, the use of 55% coal by 2030, then total transport GHG emissions will be further reduced by 0.8%-4.4%. Moreover, further reductions of GHG emissions of up to 5.6% could be achieved through technological improvement. The promotion of EVs could substantially affect the reduction of transport GHG emissions in China, despite the uncertainty of the influence intensity, which is dependent on the penetration rate of EVs, the decarbonization of the power sector, and the technological improvement efficiency of EVs and internal combustion engine vehicles.

10.
Nanoscale ; 11(32): 15131-15138, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31372609

RESUMO

The enhancement of toroic motifs through coupling toroidal moments within molecular nanomagnets is a new, interesting and relevant approach for both fundamental research and potential quantum computation applications. We investigate a Dy8 molecular cluster and discover it has a antiferrotoroic ground state with slow magnetic relaxation. The experimental characterization of the magnetic anisotropy axes of each magnetic center and their exchange interactions represents a considerable challenge due to the non-magnetic nature of the toroidal motif. To overcome this and obtain access to the low energy states of Dy8 we establish a multi-orientation single-crystal micro Hall sensor magnetometry approach. Using an effective Hamiltonian model we then unpick the microscopic spin structure of Dy8, leading to a canted antiferrotoroidic tetramer molecular ground state. These findings are supported with electrostatic calculations that independently confirm the experimentally determined magnetic anisotropy axes for each DyIII ion within the molecule.

11.
Anat Rec (Hoboken) ; 302(12): 2261-2270, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31443117

RESUMO

In recent years, the extraction fraction of volatile oil from Acorus gramineus has significant effects on anti-dementia and improving the learning and memory of animals. To date, limited studies have determined whether volatile oil from A. gramineus has the protective effect on neuronal damage. The aim of this study was to investigate the protective effects of volatile oil from A. gramineus on Alzheimer's disease (AD) mice, by means of behavior test, immunohistochemistry and western blot methods. In this study, mice were injected with Aß1-42 in the bilateral hippocampus to establish the AD model. On the seventh day after modeling, the mice with cognitive dysfunction were selected by the novel object recognition task. Subsequently, the volatile oil treatment groups underwent intragastric administration for per 10 g body weight 2.5 or 5 µL volatile oil from A. gramineus for 3 weeks. The control group and the AD group were given the same amount of saline. Our results showed that after treatment of volatile oil from A. gramineus, the number of Doublecortin and Nestin positive cells increased significantly, suggesting that the volatile oil from A. gramineus may induce the regeneration of hippocampal neurons in mice, and promote the growth of hippocampal neurons by upregulation of brain-derived neurotrophic factor, tyrosine protein kinase B, and neurotrophin-3 expression. These results might provide more experimental evidences for underlying mechanism about the neuroprotective effects of volatile oil from A. gramineus against AD relevant symptoms. Anat Rec, 302:2261-2270, 2019. © 2019 American Association for Anatomy.

12.
J Phys Chem Lett ; 10(14): 3998-4002, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31260314

RESUMO

Scanning tunneling microscopy and spectroscopy experiments under ultrahigh vacuum and low-temperature conditions have been performed on water-intercalated graphene on Pt(111). We find that the confined water layer, with a thickness around 0.35 nm, induces a strong hole doping in graphene, i.e., the Dirac point locates at round 0.64 eV above the Fermi level. This can be explained by the presence of a single "puckered bilayer" of ice-Ih, which has not been experimentally found on bare Pt(111), being confined in between graphene and Pt(111) surface. Moreover, the water intercalation makes graphene highly decoupled from the substrate, allowing us to reveal the intrinsic graphene phonons and double Rydberg series of even and odd symmetry image-potential states. Our work not only demonstrates that the electronic properties of graphene can be tuned by the confined water layer between graphene and the substrate, but also provides a generally applicable method to study the intrinsic properties of graphene as well as of other supported two-dimensional materials.

13.
Front Chem ; 7: 499, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31355189

RESUMO

Novel CsPbBr3/CdS core/shell structure quantum dots (QDs) were successfully synthesized using a facile hot-injection method. The corresponding CsPbBr3/CdS QDs based light-emitting diodes (QLEDs) were further prepared, which demonstrated the maximum luminance of 354 cd/m2 and an external quantum efficiency (EQE) of 0.4% with the current efficiency (CE) of 0.3 cd/A. Moreover, the optoelectronic performance of the CsPbBr3/CdS QDs based QLEDs exhibited a comparable enhancement in contrast to the pure CsPbBr3 QDs based QLEDs. Hypothetically, the novel CsPbBr3/CdS structure QDs introduced one new route for advanced light emission applications of perovskite materials.

16.
Endocr Pract ; 25(6): 562-571, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30865541

RESUMO

Objective: To investigate in vivo correlates of erectile dysfunction (ED) in male patients with acromegaly. Methods: Fifty-one male patients with acromegaly were assessed by the International Index of Erectile Function-5 and Acromegaly Quality of Life (Acro-QoL) questionnaires. The measurement of serum nitric oxide (NO) were performed in patients and age-matched nonacromegalic controls. Results: Among 51 patients analyzed, 32 (62.7%) had ED. Patients with ED showed lower Acro-QoL scores regarding global (69.8 ± 17.7 versus 79.4 ± 11.2; P = .035) and personal relationship dimensions (59.6 ± 22.1 versus 76.8 ± 17.6; P = .012) than non-ED patients. ED patients were older (44.5 ± 11.2 years versus 33.2 ± 8.5 years; P = .04) and showed higher growth hormone (GH) levels (15.5 µg/L [interquartile range of 9.5 to 34.5 µg/L] versus 5.9 µg/L [interquartile range of 3.4 to 13.9 µg/L]; P = .001) compared to non-ED patients. The cutoff values for identifying ED were 7.9 µg/L for random GH and 5.3 µg/L for GH nadir after oral administration of 75 g of glucose. There was no significant difference in total testosterone levels between the two groups (6.36 ± 4.24 nmol/L versus 9.54 ± 5.50 nmol/L; P = .299). The NO levels in patients with acromegaly were significantly lower than those in nonacromegalic controls (8.77 ± 1.78 µmol/L versus 19.19 ± 5.02 µmol/L, respectively; P = .049). Furthermore, the NO levels were even lower in ED patients than those in non-ED patients (5.14 ± 0.98 µmol/L versus 12.09 ± 3.44 µmol/L; P = .027). Conclusion: Our study showed that ED is prevalent in male acromegalic patients and may be associated with systemic endothelial dysfunction induced by excessive GH. Further studies investigating the mechanism of GH and ED are required. Abbreviations: Acro-QoL = Acromegaly Quality of Life; ED = erectile dysfunction; FSH = follicle-stimulating hormone; GH = growth hormone; IGF-1 = insulin-like growth factor 1; IIEF-5 = international index of erection function-5; LH = luteinizing hormone; MRI = magnetic resonance imaging; NO = nitric oxide; OGTT = oral glucose tolerance test; QoL = quality of life; ROC = receiver operating characteristic.


Assuntos
Acromegalia , Disfunção Erétil , Hormônio do Crescimento Humano , Humanos , Fator de Crescimento Insulin-Like I , Masculino , Qualidade de Vida
17.
Front Physiol ; 10: 153, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30873045

RESUMO

Ischemia reperfusion injury (IRI) is one of the most common causes of acute kidney injury (AKI). However, the pathogenesis and biomarkers predicting the progression of IRI-induced AKI to chronic kidney disease (CKD) remain unclear. A side-by-side comparison between different IRI animal models with variable ischemic duration and episodes was performed. The dynamic changes of KIM-1 and NGAL continuously from AKI to CKD phases were studied as well. Short-term duration of ischemia induced mild renal tubule-interstitial injury which was completely reversed at acute phase of kidney injury, while long-term duration of ischemia caused severe tubular damage, cell apoptosis and inflammatory infiltration at early disease stage, leading to permanent chronic kidney fibrosis at the late stage. Repeated attacks of moderate IRI accelerated the progression of AKI to CKD. Different from serum and urine levels of KIM-1 that increased at acute phase of IRI then declined gradually in chronic phase, NGAL increased continuously during AKI-to-CKD transition. Severity and frequency of ischemia injury determines the progression and outcome of ischemia-induced AKI. Inflammation, apoptosis and fibrogenesis likely participate in the progression of AKI to CKD. Both KIM-1 and NGAL enable noninvasive and early detection of AKI, but NGAL is associated better with the process of AKI-to-CKD progression.

18.
Materials (Basel) ; 12(4)2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30781599

RESUMO

There is strong interest in developing high-frequency (HF) supercapacitors or electrochemical capacitors (ECs), which can work at the hundreds to kilo hertz range for line-frequency alternating current (AC) filtering in the substitution of bulky aluminum electrolytic capacitors, with broad applications in the power and electronic fields. Although great progress has been achieved in the studies of electrode materials for ECs, most of them are not suitable to work in this high frequency range because of the slow electrochemical processes involved. Edge-oriented vertical graphene (VG) networks on 3D scaffolds have a unique structure that offers straightforward pore configuration, reasonable surface area, and high electronic conductivity, thus allowing the fabrication of HF-ECs. Comparatively, highly conductive freestanding cross-linked carbon nanofibers (CCNFs), derived from bacterial cellulose in a rapid plasma pyrolysis process, can also provide a large surface area but free of rate-limiting micropores, and are another good candidate for HF-ECs. In this mini review, advances in these fields are summarized, with emphasis on our recent contributions in the study of these materials and their electrochemical properties including preliminary demonstrations of HF-ECs for AC line filtering and pulse power storage applications.

20.
Knee ; 26(2): 339-346, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30709642

RESUMO

BACKGROUND: Injuries of the anterolateral ligament (ALL) are fairly common in patients with ruptures of the anterior cruciate ligament (ACL). Before considering repair or reconstruction of the ALL, the lack of knowledge with regard to the biomechanical behavior of this ligament must be considered. The purpose of this study was to analyze the strain of the ALL induced by tibial internal rotation at different flexion angles and find out the strain distribution features. METHODS: The ALLs of ten fresh-frozen cadaver knees were dissected. All specimens underwent tibial internal rotation from 0° to 25° at 30°, 60°, 90°, and 120° of knee flexion. Strain distribution of the ALL during internal rotation was recorded by digital image correlation (DIC). The overall strain and sub-regional strain were measured. RESULTS: The strain of the ALL increased with increasing tibial internal rotation. With 25° of internal rotation, the overall strain at each flexion angle was 12.89 ±â€¯2.73% (30°), 15.32 ±â€¯2.50% (60°), 18.94 ±â€¯2.34% (90°), and 20.10 ±â€¯3.27% (120°). The sub-regional strain was significantly different at all flexion angles. The strain of the distal 1/3 of the ALL was the greatest, followed by the middle 1/3, while the proximal 1/3 was the smallest (all P < 0.001). CONCLUSION: The ALL resisted internal rotation of the tibia by becoming more tense with increasing rotation. A significantly high strain was observed in the distal portion near the tibial insertion site of the ALL, which may suggest that this region is prone to injury with excessive internal rotation.


Assuntos
Lesões do Ligamento Cruzado Anterior/fisiopatologia , Ligamento Cruzado Anterior/fisiopatologia , Articulação do Joelho/fisiopatologia , Amplitude de Movimento Articular/fisiologia , Adulto , Idoso , Ligamento Cruzado Anterior/cirurgia , Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/métodos , Fenômenos Biomecânicos , Cadáver , Feminino , Humanos , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Tíbia/cirurgia
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