358 research outputs found

    Single-layer behavior and slow carrier density dynamic of twisted graphene bilayer

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    We report scanning tunneling microscopy (STM) and spectroscopy (STS) of twisted graphene bilayer on SiC substrate. For twist angle ~ 4.5o the Dirac point ED is located about 0.40 eV below the Fermi level EF due to the electron doping at the graphene/SiC interface. We observed an unexpected result that the local Dirac point around a nanoscaled defect shifts towards the Fermi energy during the STS measurements (with a time scale about 100 seconds). This behavior was attributed to the decoupling between the twisted graphene and the substrate during the measurements, which lowers the carrier density of graphene simultaneously

    Clinical and laboratory characteristics of systemic anaplastic large cell lymphoma in Chinese patients

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    Background: Systemic anaplastic large cell lymphoma (S-ALCL) is a rare disease with a highly variable prognosis and no standard chemotherapy regimen. Anaplastic lymphoma kinase (ALK) has been reported as an important prognostic factor correlated with S-ALCL in many but not all studies. In our study, we retrospectively analyzed 92 patients with S-ALCL from the Peking University Lymphoma Center for clinical and molecular prognostic factors to make clear the role of ALK and other prognostic factors in Han Chinese S-ALCL. Results: The majority of Chinese S-ALCL patients were young male patients (median age 26, male/female ratio 1.7) and the median age was younger than previous reports regardless of ALK expression status. The only statistically significant different clinical characteristic in S-ALCL between ALK positive (ALK(+)) and ALK negative (ALK(-)) was age, with a younger median age of 22 for ALK+ compared with 30 for ALK-. However, when pediatric patients (<= 18) were excluded, there was no age difference between ALK+ and ALK-. The groups did not differ in the proportion of males, those with clinical stage III/IV (49 vs 51%) or those with extranodal disease (53 vs 59%). Of 73 evaluable patients, the 3-year and 5-year survival rates were 60% and 47%, respectively. Univariate analysis showed that three factors: advanced stage III/IV, lack of expression of ALK, and high Ki-67 expression, were associated with treatment failure in patients with S-ALCL. However, ALK expression correlated with improved survival only in patients younger than 14 years, while not in adult patients. In multivariate analysis, only clinical stage was an independent prognostic factor for survival. Expressions of Wilms tumor 1 (WT1) and B-cell lymphoma 2 protein (BCL-2) correlated with the expression of ALK, but they did not have prognostic significance. High Ki-67 expression was also a poor prognostic factor. Conclusions: Our results show that ALK expression alone is not sufficient to determine the outcome of ALCL and other prognostic factors must be considered. Clinical stage is an independent prognostic factor. Ki-67 expression is a promising prognostic factor.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000307871100001&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701OncologyHematologySCI(E)PubMed4ARTICLE38

    The effects of fermentation and adsorption using lactic acid bacteria culture broth on the feed quality of rice straw

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    To improve the nutritional value and the palatability of air-dried rice straw, culture broth of the lactic acid bacteria community SFC-2 was used to examine the effects of two different treatments, fermentation and adsorption. Air-dried and chopped rice straw was treated with either fermentation for 30 d after adding 1.5 L nutrient solution (50 mL inocula L–1, 1.2×1012 CFU mL–1 inocula) kg–1 straw dry matter, or spraying a large amount of culture broth (1.5 L kg–1 straw dry matter, 1.5×1011 CFU mL–1 culture broth) on the straw and allowing it to adsorb for 30 min. The feed quality and aerobic stability of the resulting forage were examined. Both treatments improved the feed quality of rice straw, and adsorption was better than fermentation for preserving nutrients and improving digestibility, as evidenced by higher dry matter (DM) and crude protein (CP) concentrations, lower neutral detergent fiber (NDF), acid detergent fiber (ADF) and NH3-N concentrations, as well as higher lactic acid production and in vitro digestibility of DM (IVDMD). The aerobic stability of the adsorbed straw and the fermented straw was 392 and 480 h, respectively. After being exposed to air, chemical components and microbial community of the fermented straw were more stable than the adsorbed straw

    Spontaneous activities in baroreflex afferent pathway contribute dominant role in parasympathetic neurocontrol of blood pressure regulation

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    Aim To study the dominant role of parasympathetic inputs at cellular level of baroreflex afferent pathway and underlying mechanism in neurocontrol of blood pressure regulation. Methods Whole‐cell patch‐clamp and animal study were conducted. Results For the first time, we demonstrated the spontaneous activities from resting membrane potential in myelinated A‐ and Ah‐type baroreceptor neurons (BRNs, the 1st‐order), but not in unmyelinated C‐types, using vagus‐nodose slice of adult female rats. These data were further supported by the notion that the spontaneous synaptic currents could only be seen in the pharmacologically and electrophysiologically defined myelinated A‐ and Ah‐type baroreceptive neurons (the 2nd‐order) of NTS using brainstem slice of adult female rats. The greater frequency and the larger amplitude of the spontaneous excitatory postsynaptic currents (EPSCs) compared with the inhibitory postsynaptic currents (IPSCs) were only observed in Ah‐types. The ratio of EPSCs:IPSCs was estimated at 3:1 and higher. These results confirmed that the afferent‐specific spontaneous activities were generated from baroreflex afferent pathway in female‐specific subpopulation of myelinated Ah‐type BRNs in nodose and baroreceptive neurons in NTS, which provided a novel insight into the dominant role of sex‐specific baroreflex‐evoked parasympathetic drives in retaining a stable and lower blood pressure status in healthy subjects, particularly in females. Conclusion The data from current investigations establish a new concept for the role of Ah‐type baroreceptor/baroreceptive neurons in controlling blood pressure stability and provide a new pathway for pharmacological intervention for hypertension and cardiovascular diseases

    Comparison of survival, acute toxicities, and dose-volume parameters between intensity-modulated radiotherapy with or without internal target volume delineation method and three-dimensional conformal radiotherapy in cervical cancer patients:A retrospective and propensity score-matched analysis

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    BACKGROUND: To evaluate whether the use of the internal target volume (ITV) delineation method improves the performance of intensity‐modulated radiotherapy (IMRT) and three‐dimensional conformal radiotherapy (3DCRT) in terms of survival, acute toxicities, and dose–volume parameters. METHODS: A total number of 477 cervical cancer patients who received concurrent chemoradiotherapy (CCRT) from January 2012 to December 2016 were retrospectively analyzed. They were divided into four groups: the non‐ITV (N‐ITV) + IMRT, ITV + IMRT, N‐ITV + 3DCRT, and ITV + 3DCRT groups, with 76, 41, 327, and 33 patients, respectively. Survival analysis was performed with the Kaplan–Meier and the log‐rank tests, and acute toxicity analysis was performed with the chi‐squared test and the binary logistic regression test. Using the propensity score matching (PSM) method, 92 patients were matched among the four groups, and their dose–volume parameters were assessed with the Kruskal–Wallis method. RESULTS: The median follow‐up time was 49 months (1–119) for overall survival (OS). The 5‐year OS rate was 66.4%. The ITV delineation method was an independent prognostic factor for OS (HR [95% CI]: 0.52 [0.27, 0.98], p = 0.044) and progression‐free survival (PFS) (HR [95% CI]: 0.59 [0.36, 0.99], p = 0.045). The ITV + IMRT group had the lowest incidence rate (22%) and the N‐ITV + IMRT group had the highest incidence rate of grade ≄3 hematological toxicity (HT) (46.1%) among the four groups. The pelvic bone marrow relative V10, V20, and V30 in the N‐ITV + IMRT group was higher than those in the ITV + IMRT and N‐ITV + 3DCRT groups (p < 0.05). CONCLUSIONS: The use of ITV for IMRT treatment planning was associated with improved overall survival and progression‐free survival, with lower HT rate

    KLF7-transfected Schwann cell graft transplantation promotes sciatic nerve regeneration

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    Our former study demonstrated that KrĂŒppel-like Factor 7 (KLF7) is a transcription factor that stimulates axonal regeneration after peripheral nerve injury. Currently, we used a gene therapy approach to overexpress KLF7 in Schwann cells (SCs) and assessed whether KLF7-transfected SCs graft could promote sciatic nerve regeneration. SCs were transfected by adeno-associated virus 2 (AAV2)-KLF7 in vitro. Mice were allografted by an acellular nerve (ANA) with either an injection of DMEM (ANA group), SCs (ANA + SCs group) or AAV2-KLF7-transfected SCs (ANA + KLF7-SCs group) to assess repair of a sciatic nerve gap. The results indicate that KLF7 overexpression promoted the proliferation of both transfected SCs and native SCs. The neurite length of the dorsal root ganglia (DRG) explants was enhanced. Several beneficial effects were detected in the ANA + KLF7-SCs group including an increase in the compound action potential amplitude, sciatic function index score, enhanced expression of PKH26-labeling transplant SCs, peripheral myelin protein 0, neurofilaments, S-100, and myelinated regeneration nerve. Additionally, HRP-labeled motoneurons in the spinal cord, CTB-labeled sensory neurons in the DRG, motor endplate density and the weight ratios of target muscles were increased by the treatment while thermal hyperalgesia was diminished. Finally, expression of KLF7, NGF, GAP43, TrkA and TrkB were enhanced in the grafted SCs, which may indicate that several signal pathways may be involved in conferring the beneficial effects from KLF7 overexpression. We concluded that KLF7-overexpressing SCs promoted axonal regeneration of the peripheral nerve and enhanced myelination, which collectively proved KLF-SCs as a novel therapeutic strategy for injured nerves
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