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1.
Zhonghua Fu Chan Ke Za Zhi ; 56(8): 545-553, 2021 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-34420286

RESUMO

Objective: To study the risk factors of adverse pregnancy outcomes for induced abortion of cesarean scar pregnancy in midtrimester. Methods: A national multicenter retrospective study was conducted. A total of 154 singletons pregnant women with cesarean scar pregnancy during the second trimester induced abortion by various reasons in 12 tertiary A hospitals were selected, their pregnant outcomes were observed and the risk factors of serious adverse outcomes were analyzed with univariate and multivariate logstic regression; the role of ultrasound and MRI in predicting placenta accreta and severe adverse outcomes was evaluated, the effectiveness of uterine artery embolization (UAE) in preventing hemorrhage in pregnant women with and without placenta accreta was compared. Results: Among 154 subjects, the rate of placenta accreta was 42.2% (65/154), the rate of postpartum hemorrhage≥1 000 ml was 39.0% (60/154), the rate of hysterectomy was 14.9% (23/154), the rate of uterine rupture was 0.6% (1/154). The risk factor of postpartum hemorrhage≥1 000 ml and hysterectomy was placenta accreta (P<0.01). For each increase in the number of parity, the risk of placenta accreta increased 2.385 times (95%CI: 1.046-5.439; P=0.039); and the risk of placenta accreta decreased with increasing ultrasound measurement of scar myometrium thickness (OR=0.033, 95%CI: 0.001-0.762; P=0.033). The amount of postpartum hemorrhage and hysterectomy rate in the group with placenta accreta diagnosed by ultrasound combined with MRI were not significantly different from those in the group with placenta accreta diagnosed by ultrasound only or MRI only (all P>0.05). For pregnant women with placenta accreta, there were no significant difference in the amount of bleeding and hysterectomy rate between the UAE group [median: 1 300 ml; 34% (16/47)] and the non-embolization group (all P>0.05); in pregnant women without placenta accreta, the amount of bleeding in the UAE group was lower than that in the non-embolization group (median: 100 vs 600 ml; P<0.01), but there was no significant difference in hysterectomy rate [2% (1/56) vs 9% (3/33); P>0.05]. Conclusions: (1) Placenta accreta is the only risk factor of postpartum hemorrhage≥1 000 ml with hysterectomy for induced abortion of cesarean scar pregnancy in midtrimester; multi-parity and ultrasound measurement of scar myometrium thickness are risk factors for placenta accreta. (2) The technique of using ultrasound and MRI in predicting placenta accreta of cesarean scar pregnancy needs to be improved. (3) It is necessary to discuss of UAE in preventing postpartum hemorrhage for induced abortion of cesarean scar pregnancy in midtrimester.


Assuntos
Placenta Acreta , Embolização da Artéria Uterina , Cicatriz , Feminino , Humanos , Placenta Acreta/diagnóstico por imagem , Placenta Acreta/epidemiologia , Gravidez , Segundo Trimestre da Gravidez , Estudos Retrospectivos
2.
Science ; 373(6553): 425-430, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34261813

RESUMO

The Crab Nebula is a bright source of gamma rays powered by the Crab Pulsar's rotational energy through the formation and termination of a relativistic electron-positron wind. We report the detection of gamma rays from this source with energies from 5 × 10-4 to 1.1 peta-electron volts with a spectrum showing gradual steepening over three energy decades. The ultrahigh-energy photons imply the presence of a peta-electron volt electron accelerator (a pevatron) in the nebula, with an acceleration rate exceeding 15% of the theoretical limit. We constrain the pevatron's size between 0.025 and 0.1 parsecs and the magnetic field to ≈110 microgauss. The production rate of peta-electron volt electrons, 2.5 × 1036 ergs per second, constitutes 0.5% of the pulsar spin-down luminosity, although we cannot exclude a contribution of peta-electron volt protons to the production of the highest-energy gamma rays.

3.
Phys Rev Lett ; 126(24): 241103, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34213924

RESUMO

We report the discovery of an extended very-high-energy (VHE) gamma-ray source around the location of the middle-aged (207.8 kyr) pulsar PSR J0622+3749 with the Large High-Altitude Air Shower Observatory (LHAASO). The source is detected with a significance of 8.2σ for E>25 TeV assuming a Gaussian template. The best-fit location is (right ascension, declination) =(95.47°±0.11°,37.92°±0.09°), and the extension is 0.40°±0.07°. The energy spectrum can be described by a power-law spectrum with an index of -2.92±0.17_{stat}±0.02_{sys}. No clear extended multiwavelength counterpart of the LHAASO source has been found from the radio to sub-TeV bands. The LHAASO observations are consistent with the scenario that VHE electrons escaped from the pulsar, diffused in the interstellar medium, and scattered the interstellar radiation field. If interpreted as the pulsar halo scenario, the diffusion coefficient, inferred for electrons with median energies of ∼160 TeV, is consistent with those obtained from the extended halos around Geminga and Monogem and much smaller than that derived from cosmic ray secondaries. The LHAASO discovery of this source thus likely enriches the class of so-called pulsar halos and confirms that high-energy particles generally diffuse very slowly in the disturbed medium around pulsars.

4.
Nature ; 594(7861): 33-36, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34002091

RESUMO

The extension of the cosmic-ray spectrum beyond 1 petaelectronvolt (PeV; 1015 electronvolts) indicates the existence of the so-called PeVatrons-cosmic-ray factories that accelerate particles to PeV energies. We need to locate and identify such objects to find the origin of Galactic cosmic rays1. The principal signature of both electron and proton PeVatrons is ultrahigh-energy (exceeding 100 TeV) γ radiation. Evidence of the presence of a proton PeVatron has been found in the Galactic Centre, according to the detection of a hard-spectrum radiation extending to 0.04 PeV (ref. 2). Although γ-rays with energies slightly higher than 0.1 PeV have been reported from a few objects in the Galactic plane3-6, unbiased identification and in-depth exploration of PeVatrons requires detection of γ-rays with energies well above 0.1 PeV. Here we report the detection of more than 530 photons at energies above 100 teraelectronvolts and up to 1.4 PeV from 12 ultrahigh-energy γ-ray sources with a statistical significance greater than seven standard deviations. Despite having several potential counterparts in their proximity, including pulsar wind nebulae, supernova remnants and star-forming regions, the PeVatrons responsible for the ultrahigh-energy γ-rays have not yet been firmly localized and identified (except for the Crab Nebula), leaving open the origin of these extreme accelerators.

5.
Ann Oncol ; 32(4): 512-521, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33453391

RESUMO

BACKGROUND: This study evaluated maintenance treatment with niraparib, a potent inhibitor of poly(ADP-ribose) polymerase 1/2, in patients with platinum-sensitive recurrent ovarian cancer. PATIENTS AND METHODS: In this phase III, double-blind, placebo-controlled study conducted at 30 centers in China, adults with platinum-sensitive recurrent ovarian cancer who had responded to their most recent platinum-containing chemotherapy were randomized 2 : 1 to receive oral niraparib (300 mg/day) or matched placebo until disease progression or unacceptable toxicity (NCT03705156). Following a protocol amendment, patients with a bodyweight <77 kg or a platelet count <150 × 103/µl received 200 mg/day, and all other patients 300 mg/day, as an individualized starting dose (ISD). Randomization was carried out by an interactive web response system and stratified by BRCA mutation, time to recurrence following penultimate chemotherapy, and response to most recent chemotherapy. The primary endpoint was progression-free survival (PFS) assessed by blinded independent central review. RESULTS: Between 26 September 2017 and 2 February 2019, 265 patients were randomized to receive niraparib (n = 177) or placebo (n = 88); 249 patients received an ISD (300 mg, n = 14; 200 mg, n = 235) as per protocol. In the intention-to-treat population, median PFS was significantly longer for patients receiving niraparib versus placebo: 18.3 [95% confidence interval (CI), 10.9-not evaluable] versus 5.4 (95% CI, 3.7-5.7) months [hazard ratio (HR) = 0.32; 95% CI, 0.23-0.45; P < 0.0001], and a similar PFS benefit was observed in patients receiving an ISD, regardless of BRCA mutation status. Grade ≥3 treatment-emergent adverse events occurred in 50.8% and 19.3% of patients who received niraparib and placebo, respectively; the most common events were neutrophil count decreased (20.3% versus 8.0%) and anemia (14.7% versus 2.3%). CONCLUSIONS: Niraparib maintenance treatment reduced the risk of disease progression or death by 68% and prolonged PFS compared to placebo in patients with platinum-sensitive recurrent ovarian cancer. Individualized niraparib dosing is effective and safe and should be considered standard practice in this setting.


Assuntos
Neoplasias Ovarianas , Inibidores de Poli(ADP-Ribose) Polimerases , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica , China , Método Duplo-Cego , Feminino , Humanos , Indazóis , Quimioterapia de Manutenção , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Piperidinas , Inibidores de Poli(ADP-Ribose) Polimerases/efeitos adversos
6.
Zhonghua Er Ke Za Zhi ; 58(8): 646-652, 2020 Aug 02.
Artigo em Chinês | MEDLINE | ID: mdl-32842385

RESUMO

Objective: To analyze the clinical features of cystic fibrosis (CF) associated allergic bronchopulmonary aspergillosis (ABPA) in children. Methods: A retrospective study was performed in 22 children who were diagnosed with CF associated ABPA in Beijing Children's Hospital affiliated to Capital Medical University from March 2010 to March 2020. The clinical features, imaging characteristics, laboratory results and the prognosis were reviewed. Results: A total of 22 cases met the diagnostic criterion, including 12 males and 10 females. The age of diagnosis was (10.4±2.8) years and the age of onset was (5.5±4.4) years. Clinical manifestations included cough and expectoration (22 cases), recurrent wheezing (15 cases), hemoptysis (7 cases), failure to thrive (12 cases), pancreatitis (10 cases), hepatomegaly (7 cases), splenomegaly (4 cases) and steatorrhea (4 cases). CT scans of all the patients showed pulmonary infiltrates and central bronchiectasis, combined with mucoid impaction in 17 cases and high density mucus plug in 12 cases. Eosinophilia was found in 18 patients. Total IgE and serum levels of A. fumigatus-specific IgE were elevated in all 22 patients. Positive culture of sputum or bronchoalvedar lauage fluid for fungus were in 15 cases, with single Aspergillus infection in 8 cases and mixed Aspergillus infection in 3 cases. The predominant bacteria found in the airways were Pseudomonas aeruginosa (17 cases), followed by staphylococcas. aureus (6 cases) and stenotrophomonas. maltophilia (5 cases). Pulmonary function revealed obstructive ventilation dysfunction in 4 cases, mixed dysfunction in 11 cases, and small airway dysfunction in 4 cases. Regarding the treatment, 3 were treated only with systemic corticosteroid, while the remaining 19 cases also received antifungal agents.The follow up continued for 1-7 years, and 6 maintained remission, 10 had recurrent episodes, 1 died, and 5 lost to follow up. Conclusions: CF associated ABPA is extremely rare in China. The overlapping clinical, radiographic, and immunologic features of these two diseases make the diagnosis challenging. Systemic corticosteroids are considered the first-line therapy for these patients, and adjuvant antifungal agents may be helpful. Recurrence rate in our center is high.


Assuntos
Aspergilose Broncopulmonar Alérgica/complicações , Aspergillus fumigatus/isolamento & purificação , Fibrose Cística/complicações , Escarro/microbiologia , Aspergilose Broncopulmonar Alérgica/tratamento farmacológico , Criança , China , Fibrose Cística/diagnóstico , Fibrose Cística/microbiologia , Feminino , Glucocorticoides/uso terapêutico , Humanos , Masculino , Estudos Retrospectivos , Resultado do Tratamento
7.
Zhonghua Shao Shang Za Zhi ; 36(3): 219-223, 2020 Mar 20.
Artigo em Chinês | MEDLINE | ID: mdl-32241048

RESUMO

Objective: To evaluate the clinical effects of anterolateral thigh free flap with fascia lata in the repair of dura mater defect after resection of head squamous cell carcinoma. Methods: From June 2016 to June 2018, Xijing Hospital of Air Force Medical University applied the free transplantation of anterolateral thigh flap with fascia lata to repair the dura mater defect of 12 patients with head squamous cell carcinoma, including 9 males and 3 females, aged from 35 to 74 years. The size of scalp soft tissue defects in patients after carcinoma resection ranged from 12 cm×10 cm to 24 cm×21 cm, and the size of dura mater defect of patients ranged from 7 cm×6 cm to 16 cm×14 cm. The size of flap of patients ranged from 14 cm×12 cm to 27 cm×24 cm, and the size of fascia lata ranged from 8 cm×7 cm to 17 cm×15 cm. The superficial temporal artery and middle temporal vein were connected by end to end anastomosis with the first musculocutaneous perforating branch of the descending branch of lateral femoral artery and its accompanying vein. The flap donor area was transplanted with autologous split-thickness skin graft from trunk and fixed with packing. Postoperative survival of flaps and skin grafts was observed. The patients were followed up regularly. The cranial magnetic resonance imaging was performed to observe the recurrence of intracranial tumors and dural integrity, shape of the flap and whether the donor site region was left with significant dysfunction were observed. Results: All the flaps and skin grafts survived well in 12 patients after surgery. Ten patients had primary healing at the edge of the flap suture; 2 patients had local sinus tract formation at the suture site of flap, with a small amount of cerebrospinal fluid leakage, and were recovered after outpatient dressing change. The patients were followed up for 10 to 36 months, and 3 patients with tumors involving in the dura mater sagittal sinus region had postoperative intracranial tumor recurrence. The tumor was resected again. All the patients had good dural integrity. The flaps of all patients were in good shape, and no obvious dysfunction remained in the flap donor site. Conclusions: Free transplantation of anterolateral thigh flap with fascia lata is an effective and reliable method to repair the dura mater defect following head squamous cell carcinoma resection. It can repair the scalp and dura mater defects caused by the invasion of squamous cell carcinoma and provide possibilities for skull reconstruction.


Assuntos
Carcinoma de Células Escamosas/cirurgia , Dura-Máter , Fascia Lata/transplante , Retalhos de Tecido Biológico , Procedimentos Cirúrgicos Reconstrutivos/métodos , Transplante de Pele , Lesões dos Tecidos Moles/cirurgia , Adulto , Idoso , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Coxa da Perna , Resultado do Tratamento
8.
Nat Nanotechnol ; 15(1): 80, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31844289

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

9.
Nat Nanotechnol ; 14(12): 1123-1128, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31686006

RESUMO

Superconductivity in monolayer transition metal dichalcogenides is characterized by Ising-type pairing induced via a strong Zeeman-type spin-orbit coupling. When two transition metal dichalcogenides layers are coupled, more exotic superconducting phases emerge, which depend on the ratio of Ising-type protection and interlayer coupling strength. Here, we induce superconductivity in suspended MoS2 bilayers and unveil a coupled superconducting state with strong Ising-type spin-orbit coupling. Gating the bilayer symmetrically from both sides by ionic liquid gating varies the interlayer interaction and accesses electronic states with broken local inversion symmetry while maintaining the global inversion symmetry. We observe a strong suppression of the Ising protection that evidences a coupled superconducting state. The symmetric gating scheme not only induces superconductivity in both atomic sheets but also controls the Josephson coupling between the layers, which gives rise to a dimensional crossover in the bilayer.

10.
Zhonghua Yi Xue Za Zhi ; 99(23): 1773-1777, 2019 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-31207685

RESUMO

Objective: To investigate the value of quantitative dynamic contrast enhancement MR imaging (DCE-MRI) parameters in the prediction and evaluation of the response to neoadjuvant chemotherapy in patients with malignant sinonasal tumors by comparing the parameter values before and after chemotherapy. Methods: DCE-MRI was performed in 14 patients (6 male cases, 8 female cases, 16-83 years) with malignant sinonasal tumors before chemotherapy in Beijing Tongren Hospital from January 2012 to December 2013 in which DCE-MRI was performed in 8 patients on the 7th, 21st and 42nd days after chemotherapy. The values of quantitative parameter including K(trans), K(ep), and V(e) of the tumor were assessed and the change rate of these quantitative parameter values after chemotherapy was calculated. Results: Response to chemotherapy of the tumor was found in 11 patients with malignant sinonasal tumors,whereas no response to chemotherapy of the tumor was confirmed in 3 patients. K(trans) ((0.75±0.28)/min) and K(ep) ((3.23±1.48)/min) values of the tumor before chemotherapy in patients with response to chemotherapy were significantly bigger than those ((0.43±0.41)/min, (1.34±0.42)/min) in patients with no response to chemotherapy (all P<0.01).There was no significant difference in V(e) values between two groups (P=0.165). Compared with K(trans) values of the tumor before chemotherapy,the change rate of K(trans) values decreased more than 40% on the 7th,21st and 42nd days after chemotherapy in the patients with treatment response,whereas the change rate did not decrease significantly in the patients without treatment response. Conclusion: The bigger K(trans) and K(ep) values of the tumor before chemotherapy,the better the treatment response of the tumor to chemotherapy.


Assuntos
Meios de Contraste , Neoplasias , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Terapia Neoadjuvante , Neoplasias/diagnóstico por imagem
11.
Zhonghua Yi Xue Za Zhi ; 99(5): 333-337, 2019 Jan 29.
Artigo em Chinês | MEDLINE | ID: mdl-30772972

RESUMO

Objective: To investigate the visualization of endolymph in patients with otogenic vertigo by intravenous administration of single dose of gadolinium contrast agents and magnetic resonance three-dimensional fluid-attenuated inversion recovery sequence (3D-FLAIR MRI), and further assess the extent of endolymphatic hydrops. Methods: From Beijing Tongren Hospital of Capital Medical University between October 2017 and June 2018, 30 patients (16 males, 14 females) with unilateral otogenic vertigo were involved in this study, with the age of 30 to 68 years, mean age of (53±10) years. Eight hours after intravenous administration of single dose (0.1 mmol/kg, body weight) of gadopentetate (Gd-DTPA), 3D-FLAIR sequence was performed in 30 patients. The location of endolymphatic hydrops was observed and then the degree of hydrops was quantitatively elevated by two radiologists. The consistency test was used to analyze the location and degree of endolymphatic hydrops in the two radiologists and the paired t-test was used to compare the difference between the affected and healthy side of endolymphatic spaces of the patients with otogenic vertigo. Results: In 30 patients, the gadolinium distributed in all parts of the perilymph inside the inner ear, and can accurately outline the boundaries of the peri-and endolymph. Twenty-six patients (26/30, 86.7%) were found to have unilateral endolymphatic hydrops, including 18 mild hydrops, 8 significant hydrops. The two radiologists had a very good agreement on the assessment of endolymphatic hydrops(kappa=0.864, ICC=0.959). In the 3D-FLAIR MR images of 26 patients with endolymphatic hydrops, the saccule (26/26, 100%) had a higher rate of hydrops than the cochlea and utricle(16/26, 61.5%; 14/26, 53.8%), and two radiologists had a very good agreement on the location of endolymphatic hydrops(kappa=0.820). Moreover, there was a significantly statistical difference between the affected and healthy area of the endolymphatic space in this study (P<0.01). Conclusion: The technique of 3D-FLAIR MR imaging through single dose intravenous gadolinium injection is feasible, which can estimate endolymphatic hydrops in patients with otogenic vertigo, and accurately classify the degree of hydrops.


Assuntos
Hidropisia Endolinfática , Adulto , Idoso , Meios de Contraste , Feminino , Gadolínio , Gadolínio DTPA , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
12.
Zhonghua Shao Shang Za Zhi ; 35(1): 62-64, 2019 Jan 20.
Artigo em Chinês | MEDLINE | ID: mdl-30678403

RESUMO

Objective: To observe the effects of the method of combining free superficial temporal fascia flaps with skin grafts in repairing deep wounds in posterior ankle region of extensively burned patients. Methods: From September 2013 to February 2017, 11 extensively burned patients with deep tissue defects in posterior ankle region were treated in our unit. Two patients had tissue defects in bilateral posterior ankle regions. The wound sizes ranged from 5.8 cm×4.6 cm to 11.7 cm×5.2 cm. Free superficial temporal fascia flaps with the same sizes as the wounds were designed and resected to repair wounds in posterior ankle regions after debridement. The proximal end of superficial temporal veins and posterior tibial veins were performed with end-to-end anastomosis, and superficial temporal arteries and posterior tibial arteries were performed with end-to-side anastomosis. Skin grafts were resected to cover the superficial temporal fascia flaps according to patients' condition of donor sites. The donor sites were sutured directly. Results: All fascial flaps in 11 patients survived, while 2 skin grafts had partial necrosis, and they healed after secondary skin graft. All patients were followed up for 6 to 13 months, and the shape and function of the operation sites in all patients recovered well. Conclusions: The method of combining free superficial temporal fascia flaps with skin grafts can repair deep wounds in posterior ankle regions of extensively burned patients. It has the advantages of good appearances in the recipient sites, strong resistances to infection of fascia flaps, minimal damages to the donor sites, short course of disease, and good prognosis of patients.


Assuntos
Tornozelo , Retalhos de Tecido Biológico , Procedimentos Cirúrgicos Reconstrutivos/métodos , Transplante de Pele , Lesões dos Tecidos Moles/cirurgia , Fáscia , Humanos
13.
Acta Physiol (Oxf) ; 222(2)2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28872777

RESUMO

AIM: Accumulating evidence suggests that orexin signalling is involved in the regulation of blood pressure and cardiovascular function. However, the underlying mechanisms are not clear. Here, we test the hypothesis that upregulated orexin A signalling in the paraventricular nucleus (PVN) increases sympathetic nerve activity (SNA) through stimulating expression of proinflammatory cytokines (PICs). METHODS: In vivo sympathetic nerve recordings were performed to test the impact of PVN orexin signalling on sympathetic outflow in Sprague Dawley (SD) rats. Real-time PCR was carried out to assess effects of central administration of orexin A on PVN PICs expression in SD rats. To test whether orexin A-induced increases in PICs were exclusively mediated by orexin receptor 1 (OX1R), OX1R-expressing PC12 (PC12-OX1R) cells were incubated with different dose of orexin A, and then, PICs mRNA and immunoreactivity were measured. RESULTS: Orexin A microinjection (25 pmol) into the PVN significantly increased splanchnic SNA (93.5%) and renal SNA (83.3%) in SD rats, and these increases were attenuated by OX1R antagonist SB408124. Intracerebroventricular injection of orexin A (0.2 nmol) into SD rats increased mRNA levels of PICs including IL-1-ß (2.7-fold), IL-6 (1.7-fold) and TNF-α (1.5-fold), as well as Fra1 (1.6-fold) in the PVN. Orexin A treatment in PC12-OX1R cells resulted in a dose- and time-dependent increase in the expression of PICs and Fra1, a subunit of AP1 transcriptional factor. The increase in the PICs was blocked by AP1 blocker curcumin. CONCLUSION: Paraventricular nucleus orexin system activation is involved in SNA regulation maybe through triggering AP1-PICs pathway.


Assuntos
Citocinas/biossíntese , Orexinas/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Sistema Nervoso Simpático/metabolismo , Animais , Inflamação/metabolismo , Neurônios/metabolismo , Receptores de Orexina/metabolismo , Ratos , Ratos Sprague-Dawley
14.
Phys Rev Lett ; 119(14): 147002, 2017 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-29053311

RESUMO

By dual gating a few-layer MoS_{2} flake, we induce spatially separated electronic states showing superconductivity and Shubnikov-de Haas (SdH) oscillations. While the highly confined superconductivity forms at the K/K^{'} valleys of the topmost layer, the SdH oscillations are contributed by the electrons residing in the Q/Q^{'} valleys of the rest of the bottom layers, which is confirmed by the extracted Landau level degeneracy of 3, electron effective mass of 0.6m_{e}, and carrier density of 5×10^{12} cm^{-2}. Mimicking conventional heterostructures, the interaction between the heteroelectronic states can be electrically manipulated, which enables "bipolarlike" superconducting transistor operation. The off-on-off switching pattern can be continuously accessed at low temperatures by a field effect depletion of carriers with a negative back gate bias and the proximity effect between the top superconducting layer and the bottom metallic layers that quenches the superconductivity at a positive back gate bias.

15.
Zhonghua Yi Xue Za Zhi ; 97(5): 343-346, 2017 Feb 07.
Artigo em Chinês | MEDLINE | ID: mdl-28219190

RESUMO

Objective: To assesse the efficacy and safety of procalcitonin-guided antibiotic treatment of sepsis patients in intensive care units (ICU). Methods: A prospective, randomised, controlled trial was gone in ICU of Northern Jiangsu People's Hospital.Between January 2013 and December 2015.One hundred and fifty-six patients assessed for eligibility were randomly assigned to the procalcitonin-guided group (PCT group, 79) or to regular antibiotic group (RAT group, 77). Patients who received antibiotics for presumed infection according to principle of antimicrobial usage.In the procalcitonin-guided group, a non-binding advice to discontinue antibiotics was provided if procalcitonin concentration had decreased by 90% or more of its peak value or to 0.25 µg/L or lower.In the regular antibiotic group, patients were treated according to principle of antimicrobial usage.The general status of the patient, antimicrobial drug use time, length of ICU stay, hospital stay time, number of cases of recurrence in 28 days and number of cases of death in 28 days were compared between the two groups. Results: There were no statistical significance in age, gender, blood culture positive rate, and chronic underlying diseases (P>0.05). While APACHE Ⅱ score of PCT group was (22.7±4.7) points, which was higher than that of RAT group (19.9±4.2) (P<0.05). Log Rank test results showed that the time of antimicrobial drug usage was significantly reduced in PCT group than RAT group [days: 8.3±0.3, 95% confidence interval (95%CI 7.9-9.1) vs 10.1±0.4, 95% confidence interval (95%CI 9.2-11.3), Log Rank value 31.85, P=0.000]. There was no significant difference in length of hospital stay, ICU stay time, number of cases of recurrence in 28 days and number of death in 28 days between two groups (P>0.05). Conclusion: Procalcitonin guidance stimulates reduction of duration of treatment and daily defined doses in critically ill patients with a presumed bacterial infection.This reduction does not affect the length of hospital stay, ICU stay time, number of cases of recurrence in 28 days and number of death in 28 days.


Assuntos
Sepse , Antibacterianos , Infecções Bacterianas , Biomarcadores , Calcitonina , Peptídeo Relacionado com Gene de Calcitonina , Estado Terminal , Humanos , Unidades de Terapia Intensiva , Tempo de Internação , Estudos Prospectivos , Precursores de Proteínas , Recidiva
16.
Zhonghua Jie He He Hu Xi Za Zhi ; 40(11): 855-858, 2017 Nov 12.
Artigo em Chinês | MEDLINE | ID: mdl-29320834

RESUMO

Objective: To explore the role and mechanism of mesenchymal stem cell (MSC) in modulating human pulmonary microvascular endothelial cell (HPMECs) permeability via hepatocyte growth factor (HGF). Methods: The study introduced a co-cultured model between HPMECs and human mesenchymal stem cell conditioned media (MSC-CM) collected from MSCs after 24 h hypoxia culture, and meanwhile HGF was neutralized in MSC-CM by anti-HGF antibody respectively, followed by lipopolysaccharide (LPS) stimulation. Finally, the following measurements were performed: the permeability of HPMECs, the protein expression of vascular endothelial cadherin (VE-cadherin), Occludin in HPMECs by Western blot, HPMECs apoptosis by Annexin V-FITC/PI and HPMECs proliferation by 3-(4, 5)-dimethylthiahiazo (-z-y1)-3, 5-di- phenytetrazoliumromide(MTT). Results: Compared to LPS group (4.15±0.88), MSC-CM reduced endothelial paracellular permeability injured by LPS(1.56±0.36, P<0.01), however, the MSC-CM effect was significantly blocked by anti-HGF antibody(3.11±0.74, P<0.05). Furthermore MSC-CM significantly increased the expression of VE-cadherin(0.71±0.05 vs. 0.38±0.19, P<0.05)and Occludin protein(0.96±0.05 vs. 0.51±0.02, P<0.05) in HPMECs, which was significantly blocked by anti-HGF antibody (P<0.05). MSC-CM significantly reduced the number of early apoptotic cells (6.82±1.80 vs. 17.09±1.89, P<0.05). However, the effect of MSC-CM was significantly blocked by neutralizing HGF (12.07±0.98, P<0.01). The cell viability results by MTT assay confirmed that MSC-CM(6.82±1.80, P<0.05)restored cell viability to a greater extent than LPS stimulation only(0.47±0.09), and meanwhile the MSC-CM effect was significantly inhibited by neutralizing HGF from MSC-CM with anti-HGF antibody (0.69±0.29, P<0.05). Conclusion: HGF secreted by MSCs reduces endothelial cell paracelluar permeability induced by LPS, and the possible mechanisms include remodelling of endothelial intercellular adherence junction, promoting endothelial cell proliferation and restraining endothelial cell apoptosis.


Assuntos
Permeabilidade Capilar , Fator de Crescimento de Hepatócito , Células-Tronco Mesenquimais , Células Cultivadas , Células Endoteliais/metabolismo , Humanos , Comunicação Parácrina , Permeabilidade
17.
Neurochirurgie ; 63(1): 13-16, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28010884

RESUMO

OBJECTIVE: The aim of this study was to investigate the efficacy of lumbar cistern drainage combined with intrathecal injection of antibiotics (LCD-ITI) in treating postoperative intracranial infections of hypertensive intracerebral hemorrhage (pHIH-ICI). METHODS: Sixty pHIH-ICI patients were randomly divided into the control group and the treatment group, with 30 patients in each group. Conventional treatment was performed in the control group, while LCD-ITI was performed in the treatment group. The clinical outcomes, Glasgow Outcome Score (GOS), activities of daily living (ADL) scores, incidence rates of hydrocephalus and other indicators were compared. RESULTS: The improvement time of clinical symptoms, infection control time and hydrocephalus incidence of the treatment group were significantly lower than the control group (P<0.05). Also the infection control rate, GOS score and ADL score of the treatment group were significantly higher or better than the control group (P<0.05). CONCLUSION: LCD-ITI could improve clinical treatment and prognosis of pHIH-ICI patients.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/terapia , Hemorragia Intracraniana Hipertensiva/terapia , Vértebras Lombares/cirurgia , Hemorragia Subaracnóidea/cirurgia , Espaço Subaracnóideo/cirurgia , Atividades Cotidianas , Adulto , Idoso , Drenagem/efeitos adversos , Drenagem/métodos , Feminino , Humanos , Hemorragia Intracraniana Hipertensiva/diagnóstico , Masculino , Pessoa de Meia-Idade , Prognóstico , Hemorragia Subaracnóidea/complicações
18.
Pharmazie ; 72(8): 487-489, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29441909

RESUMO

We evaluated the effect of continuous perfusion of esmolol on cardiovascular risk during curative laparoscopic surgery for gastrointestinal cancer in elderly patients. Sixty patients with gastrointestinal cancer, aged from 60 to 80 years, were divided into an esmolol group (ES, n = 30) and a control group (NS, n = 30). ES patients were treated with esmolol at a dose of 0.3 mg/kg 3 min before tracheal intubation, and received continuous perfusion of esmolol at a dose of 50 µg/kg/min during operation. In NS, esmolol was replaced by saline. SBP/DBP, MAP, HR, SPO2, PETCO2, the depth of anesthesia and the value of RPP were recorded before anesthesia (T0), during intubation (T1), 10 min before pneumoperitoneum (T2), during pneumoperitoneum (T3), 30 min after incision (T4), at the end of surgery (T5), during extubation (T6) and 30 min after extubation (T7). The serum levels of cTnI, CK, CK-MB and LDH were measured before anesthesia, 6 and 30 h after surgery. HR, MAP, RPP at T1, T3, T6 in ES were obviously decreased compared with NS (P < 0.05). There were no significant differences between both groups at different time points with respects to the serum levels of cTnI, CK, CK-MB and LDH. No major adverse cardiocerebral event was observed in both groups in three postoperative months. The present study indicated that the application of esmolol during curative laparoscopic surgery for gastrointestinal cancer can effectively reduce the cardiovascular responses in intubation, operation and extubation, sustain hemodynamic stable, reduce myocardial oxygen consumption, and prevent perioperative adverse cardiovascular events, but had no significant myocardial protective effect.


Assuntos
Antagonistas de Receptores Adrenérgicos beta 1/administração & dosagem , Doenças Cardiovasculares/prevenção & controle , Laparoscopia/métodos , Propanolaminas/administração & dosagem , Antagonistas de Receptores Adrenérgicos beta 1/farmacologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Neoplasias Gastrointestinais/cirurgia , Humanos , Intubação Intratraqueal , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Propanolaminas/farmacologia , Fatores de Risco , Fatores de Tempo
19.
Zhonghua Shao Shang Za Zhi ; 32(10): 628-631, 2016 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-27765094

RESUMO

Patients with severe burn are characterized by strong oxidative stress and intense inflammatory response, which will cause metabolic disorder. Therefore, nutrition therapy is very important for severe burn. Nutrition therapy includes enteral nutrition (EN) and parenteral nutrition, and EN has the unique advantages. In recent years, more and more researchers focused on the EN for severe burn injuries, but there were still some confusing problems needing to solve. This article reviews the recent research about nutrition therapy for severe burn, including the route of feeding, energy requirements, and supplements of protein, carbohydrates, and microelements, and so on, so as to clarify some confusing questions about nutrition therapy for severe burn in clinical practice.


Assuntos
Queimaduras/terapia , Apoio Nutricional , Nutrição Enteral , Humanos , Nutrição Parenteral
20.
Sci Rep ; 6: 32508, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27587000

RESUMO

In the interfacial superconductor Bi2Te3/Fe1+yTe, two dimensional superconductivity occurs in direct vicinity to the surface state of a topological insulator. If this state were to become involved in superconductivity, under certain conditions a topological superconducting state could be formed, which is of high interest due to the possibility of creating Majorana fermionic states. We report directional point-contact spectroscopy data on the novel Bi2Te3/Fe1+yTe interfacial superconductor for a Bi2Te3 thickness of 9 quintuple layers, bonded by van der Waals epitaxy to a Fe1+yTe film at an atomically sharp interface. Our data show highly unconventional superconductivity, which appears as complex as in the cuprate high temperature superconductors. A very large superconducting twin-gap structure is replaced by a pseudogap above ~12 K which persists up to 40 K. While the larger gap shows unconventional order parameter symmetry and is attributed to a thin FeTe layer in proximity to the interface, the smaller gap is associated with superconductivity induced via the proximity effect in the topological insulator Bi2Te3.

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