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1.
Methods Mol Biol ; 2069: 89-94, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31523767

RESUMO

Staphylococcal protein A (SPA) consists of Fc-partial-region, X-region, and C-terminal. Spa typing is a genotyping method based on the presence of gene polymorphism in a variable number of 24 bp repeat sequences in the X-region. Spa typing allows highly discriminatory and rapid characterization and prediction of multilocus sequence typing (MLST), ribotyping, and pulsed-field gel electrophoresis (PFGE). DNA sequence-based approaches are becoming more frequently used because of the ease with which sequence data can be transferred between laboratories via the Internet.

2.
J Appl Clin Med Phys ; 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31580532

RESUMO

The incidence of brain metastases is increasing and various treatment modalities exist for brain metastases. The aim of this study was to investigate the dosimetric quality and delivery efficiency of robotic radiosurgery (CyberKnife) for multiple brain metastases compared with C-arm linear accelerator (linac) based plans. C-arm linac based plans included intensity-modulated radiation therapy (IMRT), volumetric modulated arc therapy (VMAT) and non-coplanar VMAT with 1, 3 and 5 non-coplanar arcs, respectively (NC1, NC3 and NC5). For 20 patients, six plans with a prescription dose of 30 Gy in three fractions were generated. The gradient index (GI), conformity index (CI), maximum dose (Dmax ) of organs at risk (OARs), normal brain tissue volume (V3 Gy -V24 Gy ), monitor units (MUs) and beam on time (BT) were evaluated. The GI of CyberKnife plans (3.60 ± 0.70) was lower than IMRT (6.21 ± 2.26, P < 0.05), VMAT (6.04 ± 1.93, P < 0.05), NC1 (5.16 ± 1.71, P < 0.05), NC3 (5.02 ± 1.59, P < 0.05) and NC5 (5.03 ± 1.72, P < 0.05). The CI of the VMAT plans (both coplanar and non-coplanar) was larger than IMRT and CK plans. The Dmax for most OARs of the CyberKnife plan was lower than the C-arm linac based plans, although some differences were not statistically significant. The normal brain tissue volume of CyberKnife plan was lower than the C-arm linac based plans, and the normal brain tissue volume of non-coplanar VMAT plans was lower than IMRT and VMAT plans at high-moderate dose level. However, the MUs and BT of CyberKnife plans was more than C-arm linac based plans. CyberKnife plan was better than C-arm linac based plans in protecting normal brain tissue and OARs for patients with multiple brain metastases. C-arm linac based plan with non-coplanar arc provided better protection of normal brain tissue than coplanar plan. However, the BT of CyberKnife plan was longer than C-arm linac based plans.

3.
Cancer J ; 25(5): 367-371, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31567465

RESUMO

Despite wide empirical use and demand for traditional Chinese medicine (TCM) herbs worldwide, high-quality clinical trials of TCM herbs in oncology are limited. We developed recommendations for rigorous clinical trials to evaluate their safety and efficacy for oncology patients. To accomplish this goal, the TCM & Cancer Research Committee of the Chinese Pharmaceutical Association convened a working group of oncologists, TCM experts, clinical researchers, biostatisticians, and industry/government representatives to develop principles and approaches for TCM cancer drug clinical trials. They identified 2 categories of herbal drugs based on therapeutic intent: survival improvement and symptom management. The working group also emphasized the need to adopt international standards when appropriate for TCM herbal drug approval and to develop methodology to standardize diagnostic criteria, treatment approaches, and outcome measures according to defining TCM characteristics. These recommendations aim to improve study design and methods to inform rigorous investigation of TCM herbs in patients with cancer.

4.
Chemistry ; 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31568591

RESUMO

A novel supramolecular nanocage, VMOP-31, based on polyoxovanadate as molecular building block was design and synthesized under solvothermal condition. The structure of VMOP-31 was constructed by six {V5O9Cl(COO)4} vertex and eight TATB ligands with octahedral geometry. The structure of VMOP-31 was characterized by single-crystal X-ray diffraction analysis, PXRD, FT-IR, UV-Vis and thermogravimetric analysis. Impressively, VMOP-31 exhibits highly efficiency in inhibiting cell growth of solid tumors, such as human liver cancer cells SMMC-7721, and treating liver tumor in mice, which is superior to classic cisplatin. Detailed studies reveal that the potential mechanism of cell death induced by VMOP-31 involves cell cycle arrests, DNA damage and subsequent apoptosis. Moreover, VMOP-31 exhibits negligible side effects on the mice compared to cisplatin. To the best of our knowledge, VMOP-31 is the first suparmolecular nanocage applied to against hepatic tumors both in vitro and in vivo.

5.
J Cell Biol ; 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31570500

RESUMO

The mating of budding yeast depends on chemotropism, a fundamental cellular process. The two yeast mating types secrete peptide pheromones that bind to GPCRs on cells of the opposite type. Cells find and contact a partner by determining the direction of the pheromone source and polarizing their growth toward it. Actin-directed secretion to the chemotropic growth site (CS) generates a mating projection. When pheromone-stimulated cells are unable to sense a gradient, they form mating projections where they would have budded in the next cell cycle, at a position called the default polarity site (DS). Numerous models have been proposed to explain yeast gradient sensing, but none address how cells reliably switch from the intrinsically determined DS to the gradient-aligned CS, despite a weak spatial signal. Here we demonstrate that, in mating cells, the initially uniform receptor and G protein first polarize to the DS, then redistribute along the plasma membrane until they reach the CS. Our data indicate that signaling, polarity, and trafficking proteins localize to the DS during assembly of what we call the gradient tracking machine (GTM). Differential activation of the receptor triggers feedback mechanisms that bias exocytosis upgradient and endocytosis downgradient, thus enabling redistribution of the GTM toward the pheromone source. The GTM stabilizes when the receptor peak centers at the CS and the endocytic machinery surrounds it. A computational model simulates GTM tracking and stabilization and correctly predicts that its assembly at a single site contributes to mating fidelity.

7.
Nat Neurosci ; 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31570863

RESUMO

It was recently reported that a magnetic actuator, Magneto, can control neuronal firings at magnetic strength as low as 50 mT (ref. 1), offering an exciting non-invasive approach to manipulating neuronal activity in a variety of research and clinical applications. We investigated whether Magneto can be used to manipulate electric properties of Purkinje cells in the cerebellum, which play critical roles in motor learning and emotional behaviors2. Surprisingly, we found that the application of a magnetic field did not change any electrical properties of Purkinje cells expressing Magneto, raising serious doubt about the previous claim that Magneto can readily be used as a magnetic actuator1.

8.
Phys Rev Lett ; 123(10): 100501, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31573289

RESUMO

Nonadiabatic holonomic quantum computation (NHQC) has been developed to shorten the construction times of geometric quantum gates. However, previous NHQC gates require the driving Hamiltonian to satisfy a set of rather restrictive conditions, reducing the robustness of the resulting geometric gates against control errors. Here we show that nonadiabatic geometric gates can be constructed in an extensible way, called NHQC+, for maintaining both flexibility and robustness against certain types of noises. Consequently, this approach makes it possible to incorporate most of the existing optimal control methods, such as dynamical decoupling, composite pulses, and a shortcut to adiabaticity, into the construction of single-looped geometric gates. Furthermore, this extensible approach of geometric quantum computation can be applied to various physical platforms such as superconducting qubits and nitrogen-vacancy centers. Specifically, we performed numerical simulation to show how the noise robustness in recent experimental implementations [Phys. Rev. Lett. 119, 140503 (2017)PRLTAO0031-900710.1103/PhysRevLett.119.140503; Nat. Photonics 11, 309 (2017)NPAHBY1749-488510.1038/nphoton.2017.40] can be significantly improved by our NHQC+.approach. These results cover a large class of new techniques combing the noise robustness of both geometric phase and optimal control theory.

9.
Medicine (Baltimore) ; 98(39): e17322, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31574865

RESUMO

BACKGROUND: This study will aim to assess the effectiveness of the rehabilitation training (RT) combined acupuncture for the treatment of patients with neurogenic bladder (NB) secondary to the spinal cord injury (SCI). METHODS: We will conduct a comprehensive literature search from the following databases from the inceptions to the present with no language limitation: PUBMED, EMBASE, Cochrane Library, SinoMed, Web of Science, Allied and Complementary Medicine Database, VIP, WANGFANG, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure. Additionally, we will also search gray literature, including dissertations and conference proceedings. RevMan V.5.3 software will be used for the study selection, assessment of bias of bias, and data synthesis. RESULTS: This study will synthesize the available evidence of RT combined with acupuncture for NB secondary to SCI, including episodes of urinary incontinence, urinary retention, urinary tract infection, bladder overactivity, quality of life, and adverse events. CONCLUSION: This study will determine whether RT combined acupuncture is an effective and safety therapy for NB secondary to SCI. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42019146127.

10.
Cancer Res ; 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31575547

RESUMO

Immature B cells in the bone marrow (BM) emigrate into the spleen during adult lymphopoiesis. Here, we report that emigration is shifted to earlier B-cell stages in mice with orthotopic breast cancer, spontaneous ovarian cancer, and possibly in human breast carcinoma. Using mouse and human BM aspirates and mouse models challenged with highly metastatic 4T1 breast cancer cells, we demonstrated that this was the result of secretion of thymic stromal lymphopoietin (TSLP) by cancer cells. First, TSLP downregulated surface expression of BM retention receptors CXCR4 and VLA4 in B-cell precursors, increasing their motility and, presumably, emigration. Then, TSLP supported peripheral survival and proliferation of BM B-cell precursors such as pre-B-like cells. 4T1 cancer cells used the increased pool of circulating pre-B-like cells to generate metastasis-supporting regulatory B-cells. As such, the loss of TSLP expression in cancer cells alone or TSLPR deficiency in B-cells, blocked both accumulation of pre-B-like cells in circulation and cancer metastasis, implying that the pre-B cell-TSLP axis can be an attractive therapeutic target.

11.
J Am Chem Soc ; 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31580665

RESUMO

Temporal and reversible control over protein and cell conjugations holds great potential for traceless release of antibody-drug conjugates (ADCs) on tumor sites as well as on-demand altering or removal of targeting elements on cell surface. We herein developed a bioorthogonal and traceless releasable reaction on proteins and intact cells to fulfill such purposes. Sys-tematic survey of transition metals in catalyzing the bioorthogonal cleavage reactions revealed that copper complexes such as Cu(I)-BTTAA and dual-substituted propargyl (dsPra) or propargyloxycarbonyl (dsProc) moieties offered a bioorthogonal releasable pair for reversible blockage and rescue of primary amines and phenol alcohols on small molecule drugs, protein side-chains as well as intact cell surface. For proof-of-concept, we employed such Cu(I)-BTTAA/dsProc and Cu(I)-BTTAA/dsPra pairs as a "traceless linker" strategy to construct cleavable ADCs to unleash cytotoxic compounds on cancer cells in situ, and as a "reversible modification" strategy for cell surface engineering. Furthermore, by coupling with the genet-ic code expansion strategy, we site-specifically modulated ligand-receptor interactions on live cell membrane. Together, our work expanded the transition metal-mediated bioorthogonal cleavage toolkit from terminal decaging to internal-linker breakage, which offered a temporal and reversible conjugation strategy on therapeutic proteins and cells.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31583494

RESUMO

A Gram-stain negative, aerobic, non-flagellated, non-gliding, rod-shaped bacterium, designated strain YLY04T, was isolated from the gut microflora of a sea bass (Dicentrarchus labrax L.) collected from the coast of Yuanyao Wharf, Weihai, China. Growth was found to occur at pH 6.0-9.0 (optimum, 7.0-8.0), 4-37 °C (optimum, 28-30 °C) in the presence of 0-11.0% (w/v) NaCl (optimum, 3.0-4.0%). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain YLY04T is closely related to Pelagivirga sediminicola BH-SD19T and Roseovarius antarcticus M-S13-148T. Strain YLY04T contains ubiquinone-10 as the sole respiratory quinone and summed feature 8 (C18:1ω7c and/or C18:1ω6c), cyclo-C19:0ω8c, C16:0 and 11-methyl-C18:1ω7c as the major fatty acids. The polar lipids of strain YLY04T were found to consist of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, an unidentified aminolipid, an unidentified phospholipid and three unidentified lipids. The DNA G+C content was determined to be 62.7 mol%. The phenotypic, chemotaxonomic and phylogenetic properties, and genome analysis, indicated that strain YLY04T represents a novel species within the genus Pelagivirga, for which the name Pelagivirga dicentrarchi sp. nov. is proposed. The type strain is YLY04T (= MCCC 1H00334T = KCTC 62452T).

13.
Org Biomol Chem ; 17(36): 8364-8368, 2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31478050

RESUMO

A method for metal-free, 1,3-dibromo-5,5-dimethylhydantoin mediated methyl C(sp3)-H bond azolation of thioanisoles has been developed, affording a facile route for the construction of nitrogen-functionalized thioanisoles, possibly via a nitrogen-centered radical process. This reaction represents an important addition to the limited number of existing methods for the methyl C(sp3)-H bond functionalization of thioanisoles, and may find practical application in the synthesis of nitrogen-alkylated azoles.

14.
J Mater Chem B ; 7(36): 5461-5464, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31490496

RESUMO

A cellulose paper-based biosensor was developed for the equipment-free and naked-eye detection of a transcription factor (TF) using dopamine as the signal-responsive material based on exonuclease III-assisted cycling amplification. Compared with other TF biosensors, the proposed biosensor demonstrates low-cost, portable, disposable, and naked-eye detection features.

15.
Int J Surg Pathol ; : 1066896919873078, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31526158

RESUMO

Dedifferentiated liposarcoma rarely occurs in the esophagus. It always has atypical clinical manifestations and different pathologic features, which usually lead to misdiagnosis and mistreatment. Given its poor prognosis, early and accurate diagnosis is of the utmost importance. The accumulation of similar cases is critical for surgeons and pathologists to raise awareness of such tumors. This report aims to discuss the diagnosis and provide a reference for the clinical diagnosis and treatment for pathologists and clinicians.

16.
Environ Int ; 133(Pt A): 105159, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31521815

RESUMO

China ranks the top in global annual rice output. However, extensive mining and smelting has led to elevated arsenic (As) in paddy soils, potentially imperiling local population health and sustainable rice production in the country. Under flooded condition, reductive As mobilization generally occurs, providing a unique advantage for soil As removal. In this study, we explore the depletion magnitude of labile As from paddy soils through cycling of flooding-drainage with three distinct co-strategies, i.e. (1) no soil disturbance with spontaneously established hygrophyte plants, (2) selective fertilization to enhance soil As release, and (3) soil ploughing following each drainage. After 151 days of flooding with periodic drainage, diffusive gradients in thin film (DGT)-labile As through 0-14 cm soil profile with hygrophyte plants growing decreased from initial 292 µg l-1 to well below the required threshold level (57-77 µg l-1) for safe rice production. Correspondingly, an average of 22.9% of total soil As was removed, with up to 76.7% of As bound to amorphous Fe hydroxides being stripped in this treatment. In the following rice cultivation, inorganic As in the polished rice from the naturally vegetated treatment (0.15 mg kg-1) fell successfully below the Chinese food safety standard (0.2 mg kg-1). The results highlight that As removal from paddy soils with native hygrophyte under shallow flooded condition can decrease soil bioavailable As specifically to safe levels within a relatively short period, and thus provides a novel and quite cost-effective pathway securing rice production.

18.
Zhongguo Zhen Jiu ; 39(9): 1024-6, 2019 Sep 12.
Artigo em Chinês | MEDLINE | ID: mdl-31544397

RESUMO

An experimental device is designed to solve the problem of fixing rabbits and providing moxibustion treatment at the same time. The device includes a rabbit fixing box and a moxibustion shelf. The rabbit fixing box and the moxibustion shelf are detachable, and could be used for moxibustion at the chest-back and abdomen of rabbits. A moxibustion device is placed on the moxibustion shelf. The moxibustion device can be moved forward, backward, leftward, rightward, upward and downward on the moxibustion shelf. It meets the requirements of moxibustion at multiple meridians or acupoints on the chest-back and abdomen at the same time. The moxibustion device is equipped with moxa cone or stick, which not only ensures the full burning of moxa, but also prevents the falling of moxa from hurting rabbits. In conclusion, the device has novel and unique structure, is safe and reliable, and easy to operate. It is an innovation in the experimental device of moxibustion, which could promote the animal experiment of moxibustion.

19.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(10): 1260-1264, 2019 Oct 15.
Artigo em Chinês | MEDLINE | ID: mdl-31544436

RESUMO

Objective: To study the anteromedial cortical morphology of intertrochanteric fracture with CT three-dimensional reconstruction technique, and to provide a reference for further study of cortical buttress reduction theory. Methods: CT data of 75 patients with unstable intertrochanteric fracture with complete imaging data treated between January 2016 and January 2019 were retrospectively analyzed, including 32 males and 43 females, aged 65-98 years (mean, 79.8 years). According to AO/Orthopaedic Trauma Association typing of 2018 edition, there were 46 cases of 31-A2.2 type and 29 cases of 31-A2.3 type. The image processing techniques such as segmentation modeling and virtual reset were performed. The thickness of the cortex at the anteromedial corner, the angle between the anterior wall fracture line and the coronal horizontal line, the angle between the medial wall fracture line and the sagittal horizontal line, the width of the cortex supported by the medial wall were measured, and the morphology of the cortical bone at the anteromedial corner were observed. Results: The angle between the anterior wall fracture line and the coronal horizontal line was 51.8-72.6°, with an average of 62.4°; the angle between the medial wall fracture line and the sagittal horizontal line ranged from 17.6° to -47.3°, with an average of -15.8°; the thickness of the cortex at the anteromedial angle was 3.6-6.1 mm, with an average of 4.4 mm; and the width of the cortex supported by the medial wall was 14.3-21.2 mm, with an average of 16.8 mm. The morphology of the cortical bone at the anteromedial corner had 3 forms: angle with femoral neck axis >90°, 57 cases (76.0%); perpendicular to femoral neck axis, 7 cases (9.3%); angle with femoral neck axis <90° (including reverse angle), 11 cases (14.7%). Conclusion: CT three-dimensional reconstruction can clearly show the cortical morphology and the direction of the fracture line of intertrochanteric fracture, which can indicate the stability of the intertrochanteric fracture after reduction, and has a good guiding on the form of cortical buttress reduction.

20.
J Am Chem Soc ; 141(38): 15166-15173, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31492054

RESUMO

Aggregation induced-emission (AIE) and antenna effects are important luminescence behaviors. Thus, investigating their emission mechanisms and revealing their behaviors have become critical but challenging. Here we design and prepare metal-organic frameworks (MOFs) with an AIE ligand (i.e., tetrakis(4-carboxyphenyl)pyrazine (L1)) and Ln3+ ions (including Eu3+, Tb3+, and Gd3+). The emission from L1 is gradually enhanced during the formation of the MOFs because coordination restricts the intramolecular rotation. Thus, the emission is called as coordination-induced emission (CIE) with the same restriction of intramolecular rotation mechanism as AIE. Meanwhile, benzene rings twist to adapt to the MOFs' rigid structure, so the emission blueshifts gradually, as an additional evidence of CIE. Both AIE and CIE are "rotation-restricted emission (RRE)". Eu3+ ions exhibit the strongest emission with gradually enhanced intensity during the formation of L1-Eu MOF. Combined with emission properties from Tb3+ and Gd3+ ions, the antenna effect is verified. We also validate the conditions for the efficient sensitization of Ln3+ ions experimentally and refresh the threshold value of the energy gap between triplet state of a ligand and excited state of Ln3+ ions to 3000 cm-1. Thus, RRE and antenna effects are revealed and validated simultaneously. Because CIE of L1 and antenna effect emission from Eu3+ ions are enhanced simultaneously as strong dual emissions, ratiometric fluorescence detection is realized with the detection of arginine as a model. Our results incorporate AIE and CIE into RRE, which provides explicit information for the construction and application of emission systems with AIE ligands as building blocks. MOFs are also extended to explore the emission mechanism and the energy transfer between ligands and metal ions.

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