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2.
Arq Bras Cardiol ; 116(1): 100-105, 2021 01.
Artigo em Inglês, Português | MEDLINE | ID: mdl-33566972

RESUMO

BACKGROUND: Image quality and radiation dose are optimized with a slow, steady heart rate (HR) when imaging the coronary arteries during cardiac computed tomography angiography (CCTA). The safety, efficacy, and protocol for HR reduction with beta blocker medication is not well described in a pediatric patient population. OBJECTIVE: Provide a safe and efficient metoprolol dose protocol to be used in pediatric outpatients undergoing CCTA. METHODS: We conducted a retrospective review of all pediatric outpatients who received metoprolol during CCTA. Demographic and clinical characteristics were summarized and the average reduction in HR was estimated using a multivariate linear regression model. Images were evaluated on a 1-4 scale (1= optimal). RESULTS: Seventy-eight pediatric outpatients underwent a CCTA scan with the use of metoprolol. The median age was 13 years, median weight of 46 kg, and 36 (46%) were male. The median doses of metoprolol were 1.5 (IQR 1.1, 1.8) mg/kg and 0.4 (IQR 0.2, 0.7) mg/kg for oral and intravenous administrations, respectively. Procedural dose-length product was 57 (IQR 30, 119) mGy*cm. The average reduction in HR was 19 (IQR 12, 26) beats per minute, or 23%. No complications or adverse events were reported. CONCLUSION: Use of metoprolol in a pediatric outpatient setting for HR reduction prior to CCTA is safe and effective. A metoprolol dose protocol can be reproduced when a slower HR is needed, ensuring faster acquisition times, clear images, and associated reduction in radiation exposure in this population. (Arq Bras Cardiol. 2021; 116(1):100-105).


Assuntos
Doença da Artéria Coronariana , Metoprolol , Adolescente , Criança , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Frequência Cardíaca , Humanos , Masculino , Metoprolol/efeitos adversos , Pacientes Ambulatoriais , Doses de Radiação , Estudos Retrospectivos
3.
Artigo em Inglês | MEDLINE | ID: mdl-33547021

RESUMO

BACKGROUND: Cardiac computed tomography (CT) is increasingly used in pediatric patients with congenital heart disease (CHD). Variability of practice and of comprehensive diagnostic risk across institutions is not known. METHODS: Four centers prospectively enrolled consecutive pediatric CHD patients <18 years of age undergoing cardiac CT from January 6, 2017 to 1/30/2020. Patient characteristics, cardiac CT data and comprehensive diagnostic risk were compared by age and institutions. Risk categories included sedation and anesthesia use, vascular access, contrast exposure, cardiovascular medication, adverse events (AEs), and estimated radiation dose. RESULTS: Cardiac CT was performed in 1045 pediatric patients at a median (interquartile range, IQR) age of 1.7 years (0.3, 11.0). The most common indications were arterial abnormalities, suspected coronary artery anomalies, functionally single ventricle heart disease, and tetralogy of Fallot/pulmonary atresia. Sedation was used in 8% and anesthesia in 11% of patients. Peripheral vascular access was utilized for 93%. Median contrast volume was 2 â€‹ml/kg. Beta blockers were administered in 11% of cases and nitroglycerin in 2% of cases. The median (IQR) total procedural dose length product (DLP) was 20 â€‹mGy∗cm (10, 50). Sedation, vascular access, contrast exposure, use of cardiovascular medications and radiation dose estimates varied significantly by institution and age (p â€‹< â€‹0.001). Seven minor adverse events (0.7%) and no major adverse events were reported. CONCLUSION: Cardiac CT for CHD is safe in pediatric patients when appropriate CT technology and expertise are available. Scans can be acquired at relatively low radiation exposure with few minor adverse events.

4.
Hernia ; 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33400031

RESUMO

PURPOSE: Intraoperative drain placement during an open transversus abdominis release (TAR) is common practice. However, evidence detailing the optimal timing of drain removal is lacking. Surgical dogma teaches that drains should remain in place until output is minimal. This practice increases the risk of drain-associated complications (infection, pain, and skin irritation) and prolongs the burden of surgical drain maintenance. The objective of this study is to review infectious outcomes following TAR with early or late drain removal. METHODS: Patients who underwent an open bilateral TAR from 1/2018 to 1/2020 were eligible for the study. Prior to 2019, one of the two intraoperative drains was left in place at discharge. In 2019, clinical practice shifted to remove both drains at hospital discharge irrespective of output. The rate of infectious morbidity was compared between the two cohorts. RESULTS: A total of 184 patients were included: 89 late and 95 early drain removal. No differences in wound complications existed between the two cohorts: surgical site occurrence (SSO): 21.3% vs. 18.9% (p = 0.68); surgical site infection (SSI): 14.6% vs. 10.5% (p = 0.40); abscess: 8.9% vs. 4.2% (p = 0.20); seroma: 6.7% vs. 10.5% (p = 0.36); cellulitis: 14.6% vs. 8.4% (p = 0.19%); or SSO requiring procedural intervention (SSOPI): 5.6% vs. 5.2% (p = 0.92). Rates of antibiotic prescription and 30-day readmission were also similar (p = 0.69 and p = 0.89). CONCLUSIONS: Early removal of abdominal wall surgical drains at discharge irrespective of drain output does not increase the prevalence of infectious morbidity following TAR. It is likely safe to remove all drains at discharge regardless of drain output.

5.
Zhonghua Xue Ye Xue Za Zhi ; 41(11): 890-895, 2020 Nov 14.
Artigo em Chinês | MEDLINE | ID: mdl-33333690

RESUMO

Objective: To evaluate the safety and efficacy of eltrombopag combined with immunosuppressive therapy in patients with aplastic anemia (AA) in China. Methods: We investigated and analyzed the clinical data of AA patients from 14 hematological treatment centers who were treated with oral eltrombopag for at least 3 mon. Results: We enrolled 56 AA patients, including 19 treatment-naïve patients and 37 IST-refractory patients. The median administration period for eltrombopag was 7 (3-31) months, and the median maximum stable dosage was 75 mg/d (50-150 mg/d) . The 3-month hematological response (HR) rate was 60%, and the complete response (CR) rate was 30% in 10 SAA patients who were treated with first-line eltrombopag and standard IST (ATG+CsA) . Eight of 9 eltrombopag and CsA ± androgen first-line treated SAA patients responded (8/9, 89%) and 4 (44%) gave CR. The overall HR and CR rates were 79% and 52.6%, respectively, among these 19 patients by the end of the follow-up period. Of the 19 AA patients who were refractory to CsA ± androgen, 11 achieved HR (57.9%) at 3 mon, and the best HR rate was 44% in standard IST (ATG+CsA) refractory 18 patients after eltrombopag treatment. Fifty-one percent of the patients experienced mild or moderate adverse events, and gastrointestinal discomfort was the most common adverse effect reported by the study subjects. Conclusion: Adding Eltrombopag in first-line IST can accelerate the acquisition and improve the quality of hematological responses in AA patients. AA with relatively more residual hematopoietic cells may be well treated with eltrombopag and non-ATG IST. Eltrombopag can be used as salvage therapy for CsA±androgen refractory patients. Eltrombopag was generally safe and well tolerated by AA patients in China.


Assuntos
Anemia Aplástica , Benzoatos/uso terapêutico , Hidrazinas/uso terapêutico , Pirazóis/uso terapêutico , Anemia Aplástica/tratamento farmacológico , Soro Antilinfocitário , China , Ciclosporina , Humanos , Imunossupressores , Inquéritos e Questionários , Resultado do Tratamento
6.
Zhonghua Xue Ye Xue Za Zhi ; 41(10): 806-810, 2020 Oct 14.
Artigo em Chinês | MEDLINE | ID: mdl-33190436

RESUMO

Objectives: To explore changes in the quality of life(QoL)in patients with non-severe aplastic anemia(NSAA)after 2 years of cyclosporine A(CsA)therapy, and possible factors may affect the QoL. Methods: Patients with de novo NSAA from January 2014 to 2016 who had been treated with only CsA for at least 2 years in the outpatient department of Peking Union Medical College Hospital were instructed to fill-in the SF-36 form before and after 2 years of CsA treatment. Data from NSAA were compared with those of normal controls; patients' information such as age, sex, education, annual income, type of payment, and compliance were collected, disease severity and response to treatment were also evaluated. Results: A total of 52 patients were included in our study with 27(51.9%)men and 25(48.1%)women, with the medium age of 48(21-85)years. After 2 years of treatment, 15(28.8%)patients achieved complete response(CR), 25(48.1%)achieved partial response(PR), and 12(23.1%)patients had no response(NR). The overall response rate(ORR)was 76.9%. Before the therapy, SF-36 scores in patients with NSAA were significantly lower than that of normal controls either in physical or mental component summaries(P<0.05). However, after 2 years of therapy, patients with NSAA had significant improvement of mental component summaries and recovered to normal with even higher scores in mental health(MH)(65.9±17.6 vs 59.7±22.9, P=0.014)and energy/vitality(VT)(58.8±20.1 vs 52.3±20.9, P=0.023)compared with normal controls, although they still had comparatively lower scores in physical component summaries. No associations were found between QoL and age, sex, educational level, family income, type of payment, patient adherence, or transfusion dependency. Patients with higher ECOG (the Eastern Cooperative Oncology Group score)at the beginning experienced greater progress in QoL compared to those with lower ECOG. Both patients with CR and PR had shown significant improvement in QoL. Conclusion: Patients with NSAA had impaired QoL compared with normal patients. CsA treatment can improve the QoL, especially in mental component summaries. Patients can benefit from the treatment regardless of their social status, and patients with lower ECOG at the beginning seem to benefit more from the therapy.

8.
Ann Oncol ; 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33130217

RESUMO

BACKGROUND: Polymeric micellar paclitaxel (pm-Pac) is a novel Cremophor EL-free, nanoparticle micellar formulation of paclitaxel. We aimed to compare the efficacy and safety between pm-Pac plus cisplatin and solvent-based paclitaxel (sb-Pac) plus cisplatin in advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: A total of 448 stage IIIB to IV NSCLC patients were randomly assigned (2:1) to receive six 3-week cycles of either pm-Pac (230 mg/m2) plus cisplatin (70 mg/m2; n = 300), followed by dose escalation of pm-Pac to 300 mg/m2 from the second 3-week cycle if prespecified toxic effects were not observed after the first cycle, or sb-Pac (175 mg/m2) plus cisplatin (70 mg/m2; n = 148). The primary end point was objective response rate (ORR) assessed by independent review committees (IRCs). The secondary end points included IRC-assessed progression-free survival (PFS), overall survival (OS), and safety. RESULTS: Patients in the pm-Pac-plus-cisplatin group showed significant improvements in IRC-assessed ORR compared with those in the sb-Pac-plus-cisplatin group (50% versus 26%; rate ratio 1.91; P < 0.0001). Additionally, subgroup analysis showed that a higher ORR was consistently observed in both squamous and nonsquamous histological types. IRC-assessed median PFS was significantly higher in the pm-Pac-plus-cisplatin group than in the sb-Pac-plus-cisplatin group (6.4-month versus 5.3-month; hazard ratio 0.63; P = 0.0001). Median OS was not significantly different between the two groups. The incidence of treatment-related serious adverse events (9% versus 18%; P = 0.0090) was significantly lower in the pm-Pac-plus-cisplatin group than in the sb-Pac-plus-cisplatin group. CONCLUSION: Pm-Pac plus cisplatin yielded superior ORR and PFS along with a favorable safety profile and should become an option for patients with advanced NSCLC. CLINICAL TRIAL IDENTIFIER: ClinicalTrials.gov NCT02667743; https://clinicaltrials.gov/ct2/show/NCT02667743.

9.
Zhonghua Yi Xue Za Zhi ; 100(43): 3437-3442, 2020 Nov 24.
Artigo em Chinês | MEDLINE | ID: mdl-33238675

RESUMO

Objective: To compare the degenerative changes of adjacent segments after posterior lumbar fusion surgery using cortical bone trajectory (CBT) screws and pedicle screws (PS) in lumbar spinal degenerative disease. Methods: According to certain inclusion and exclusion criteria, prospective non-randomized study on cases of the single-segment lumbar spinal fusion surgery using cortical bone trajectory screws fixation and pedicle screws fixation in Beijing Chao-Yang Hospital from January 2015 to February 2016 was performed. The intervertebral space height (ISH), foramen height (FH), foramen width (FW), cephalad adjacent segment (CAS) and intervertebral disc degeneration grades at MRI scans were measured before surgery and during follow-up. Clinical symptoms were evaluated by Oswestry Dysfunction Index (ODI) score and pain visual analogue scale (VAS) before and during the follow-up. Radiologic adjacent segment degeneration (R-ASD) and symptomatic adjacent segment disease (S-ASD) patients were diagnosed during the follow-up. Paired sample t test was performed when data were compared before surgery and during follow-up. Results: A total of 69 patients were included in the study, 33 in the CBT group (male/female, 15/18), with an average age of (65±11) years, and 36 in the PS group (male/female, 17/19), with an average age of (64±10) years. The follow-up time was no less than 36 months. At the last follow-up, the ISH of the adjacent segments in the CBT group were not statistically different from that before surgery; the ISH of the adjacent segments in the PS group were significantly reduced compared with that before surgery (t=6.78, P<0.05). The loss of ISH, FH, and FW in the adjacent segments in the CBT group were smaller than those in the PS group, and the differences were statistically significant. During follow-up, 4 cases (12.1%) of R-ASD and no S-ASD were found in the CBT group, while 12 cases (33.3%) of R-ASD appeared in the PS group, which was significantly higher than that in the CBT group (χ(2)=4.35, P=0.04). According to MRI, the adjacent discs of PS group had significantly more severe degeneration at the last follow-up than the CBT group (Z=-2.14, P=0.03). Conclusions: Compared with the PS fixation fusion, the CBT screw fixation can effectively reduce the occurrence of adjacent segment degeneration.


Assuntos
Degeneração do Disco Intervertebral , Parafusos Pediculares , Fusão Vertebral , Idoso , Osso Cortical , Feminino , Humanos , Degeneração do Disco Intervertebral/cirurgia , Vértebras Lombares , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
11.
J Am Soc Echocardiogr ; 33(10): e1-e48, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33010859

RESUMO

The American College of Cardiology (ACC) collaborated with the American Heart Association, American Society of Echocardiography, Heart Rhythm Society, International Society for Adult Congenital Heart Disease, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, Society for Cardiovascular Magnetic Resonance, and the Society of Pediatric Echocardiography to develop Appropriate Use Criteria (AUC) for multimodality imaging during the follow-up care of patients with congenital heart disease (CHD). This is the first AUC to address cardiac imaging in adult and pediatric patients with established CHD. A number of common patient scenarios (also termed "indications") and associated assumptions and definitions were developed using guidelines, clinical trial data, and expert opinion in the field of CHD.1 The indications relate primarily to evaluation before and after cardiac surgery or catheter-based intervention, and they address routine surveillance as well as evaluation of new-onset signs or symptoms. The writing group developed 324 clinical indications, which they separated into 19 tables according to the type of cardiac lesion. Noninvasive cardiac imaging modalities that could potentially be used for these indications were incorporated into the tables, resulting in a total of 1,035 unique scenarios. These scenarios were presented to a separate, independent panel for rating, with each being scored on a scale of 1 to 9, with 1 to 3 categorized as "Rarely Appropriate," 4 to 6 as "May Be Appropriate," and 7 to 9 as "Appropriate." Forty-four percent of the scenarios were rated as Appropriate, 39% as May Be Appropriate, and 17% as Rarely Appropriate. This AUC document will provide guidance to clinicians in the care of patients with established CHD by identifying the reasonable imaging modality options available for evaluation and surveillance of such patients. It will also serve as an educational and quality improvement tool to identify patterns of care and reduce the number of Rarely Appropriate tests in clinical practice.

12.
Acta Endocrinol (Buchar) ; 16(2): 129-135, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33029227

RESUMO

Background: Thyroid hormone participates in lipid metabolism regulation. However, the effects on triacyleride or triacylglycerol metabolism are complex and not fully clarified yet. In this study, we try to identify novel thyroid hormone-targeting lipogenic metabolic genes and analyze their molecular regulative mechanism. Method: Thirty-five promoters of twenty-nine human lipogenic regulative enzyme genes were constructed into pXP1 luciferase reporter plasmid (PFK2/FBP2-luc) and transfected into HeGP2 cells, respectively. Gene expression induced by triiodothyronine (T3) was detected by luciferase assay. The T3-activated gene promoter was then analyzed by sequence analysis, deletion and mutation, and electrophoretic mobility shift assay (EMSA). Results: After 10 nM T3 stimulation for 36 h, phosphogluconate dehydrogenase, malic enzyme, Glycerol-3-phosphate acyltransferase (GPAT) 3, and 1-acylglycerol-3-phosphate O-acyltransferase (AGPAT) 2 were significantly activated, respectively. A AGGTCA-like-direct-repeat-4 consensus thyroid hormone response element (DR4-TRE)-like sequence was found in the GPAT3 promoter, which was then verified to be necessary for T3-induced GPAT3 activation by gene deletion and mutation analysis. EMSA further identified that T3-thyroid receptor (TR) α-retinoid-X receptor (RXR) complex directly bound on the GPAT3 promoter. Conclusion: Triiodothyronine could activate the GPAT3 through DR4-TRE-like sequence binding to participate in lipogenic regulation. AGPAT2 may be another thyroid hormone target enzyme.

14.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(9): 942-946, 2020 Sep 06.
Artigo em Chinês | MEDLINE | ID: mdl-32907282

RESUMO

Objective: Aanalysis the effect of booster one dose of hepatitis B vaccine after 21-32 years of primary immunization in Zhengding Country of Hebei Province. Methods: A total of 322 participants who were born between 1986 and 1996, received a full course of primary vaccination with plasma-derived hepatitis B vaccine (HepB), had no experience with booster vaccination, were HBsAg, anti-HBcnegative, had anti-HBs<10 mIU/ml, completed the booster and had laboratory results were enrolled between August 2017 to February 2018. A simple random method was uesd to randomly assigned 322 subjects to two groups, receiving a booster dose of HepB derived from either Saccharomyces cerevisiae ï¼»HepB (SC), (151 cases)ï¼½ or Chinese hamster ovary-derived HepB ï¼»HepB (CHO), (171 cases)ï¼½, the dose was 20 µg. Blood samples were collected 30 days after boosting and quantitatively tested for the geometric mean concentration (GMC) of anti-HBs to assess immunological effect. The related influencing factors of GMC and seroconversion rates of anti-HBs were analyzed by multiple linear regression and multivariate logistic regression models. Results: The 266 subjects (82.61%) had anti-HBs≥ 10 mIU/ml, and GMC was (131.63±12.94) mIU/ml.The seroconversion rates of anti-HBs in the anti-HBs<2.5 mIU/ml group and 2.5-10 mIU/ml group were 74.54% (161 cases) and 99.06% (105 cases), respectively (P<0.001).The seroconversion rates of anti-HBs after one dose of HepB (CHO) was higher than that of one dose of HepB (SC), the seroconversion rates were 87.13% (149 cases) and 77.48% (117 cases), respectively (P=0.023). Participants boostered with HepB (CHO) was the factor influencing the effect of strengthening immunization compared with boostered with HepB (SC), and OR (95%CI) was 1.91 (1.02-3.56) (P=0.042).Compared with anti-HBs<2.5 mIU/ml, prebooster anti-HBs was between 2.5 mIU/ml and 10 mIU/ml was the related factor of seroconversion rates of anti-HBs after booster immunization, and OR (95%CI) was 36.15 (4.91-266.02) (P<0.001). Conclusion: Participants boostered withone dose of HepB had a good immune response. Pre-booster anti-HBs concentration and a variety of vaccine were related factors of immune response.


Assuntos
Vacinas contra Hepatite B , Hepatite B/prevenção & controle , Animais , Células CHO , Cricetinae , Cricetulus , Seguimentos , Anticorpos Anti-Hepatite B , Antígenos de Superfície da Hepatite B , Imunização Secundária , Vacinação
15.
Zhonghua Xue Ye Xue Za Zhi ; 41(8): 637-642, 2020 Aug 14.
Artigo em Chinês | MEDLINE | ID: mdl-32942816

RESUMO

Objectives: To compare the efficacy of cyclosporin A (CsA) alone and CsA combined with recombined human thrombopoietin (rhTPO) in patients with non-severe aplastic anemia (NSAA) . Methods: Data from 83 patients with NSAA between August 2014 and February 2019 were collected retrospectively. The study population included 35 men and 48 women, with a median age of 45 years (14-85 years) . Among them, 57 had been treated with CsA + rhTPO, TPO was administered at 15 000 U QD for 7 days, once a month for 3 months, and the other 26 patients with compatible baseline characters were treated with CsA alone. All the enrolled patients had been treated with CsA for at least 6 months and were followed up for at least 1 year. The efficacy and outcome were compared between the two groups. Results: Total 23 men and 34 women, with a median age of 46 years (14-85 years) were treated with CsA + rhTPO. The median duration of CsA treatment was 17 (8-28) months, and the patients were followed up for a median of 27 (12-45) months. Total 12 men and 14 women, with a median age of 40 years (20-64) were treated with CsA alone. The median duration of CsA treatment was 19 months (9-30 months) , and the median follow-up duration was 29 months (16-66 months) . There was no significant difference in the baseline characteristics of the two groups (P>0.05) . There was no significant difference in the CR and OR rates of the two groups at 1, 3, 6, 12, and 24 months of treatment (P>0.05) . The change in the platelet level for the CsA + rhTPO treated group after 1 month[8 (-12-86) ×10(9)/L vs. 3 (16-57) ×10(9)/L, P=0.029) , 3 months[24 (-6-102) ×10(9)/L vs. 7 (-9-76) ×10(9)/L, P=0.006], and 6 months[33.5 (-4-123) ×10(9)/L vs. 12.5 (-14-109) ×10(9)/L, P=0.048] of treatment was higher than that in the CsA alone group, while no significant difference was found between the two groups at other time points. There was no significant difference in the change in the megakaryocyte level between the two groups[3 (0-4) vs. 2 (0-5) , z=-0.868, P=0.385] after 6 months of treatment. Apart from 10.5% (6/57) of the patients in the CsA + rhTPO treated group who reported soreness at the injection site, there was no other significant difference between the two groups in terms of adverse effects. During the follow-up period, there were two cases of increasing paroxysmal nocturnal hemoglobinuria clone to over 10%, one in the CsA + rhTPO treated group, the other in the CsA alone group; and there was one case of progression to SAA in the CsA + rhTPO treated group; while no case of death or thromboembolic event (TEE) , fibrosis or reticulin proliferation, progression to myelodysplastic syndrome (MDS) , or acute myeloid leukemia was observed in either group. There was one case of progression to SAA in the CsA + rhTPO treated group but none in the CsA alone group. Conclusion: Compared to CsA alone, CsA + rhTPO treatment can accelerate the recovery of the platelet level with acceptable adverse effects.


Assuntos
Anemia Aplástica , Ciclosporina/uso terapêutico , Trombopoetina/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Proteínas Recombinantes , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
17.
Nat Commun ; 11(1): 4037, 2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32788704

RESUMO

Excitons with binding energies of a few hundreds of meV control the optical properties of transition metal dichalcogenide monolayers. Knowledge of the fine structure of these excitons is therefore essential to understand the optoelectronic properties of these 2D materials. Here we measure the exciton fine structure of MoS2 and MoSe2 monolayers encapsulated in boron nitride by magneto-photoluminescence spectroscopy in magnetic fields up to 30 T. The experiments performed in transverse magnetic field reveal a brightening of the spin-forbidden dark excitons in MoS2 monolayer: we find that the dark excitons appear at 14 meV below the bright ones. Measurements performed in tilted magnetic field provide a conceivable description of the neutral exciton fine structure. The experimental results are in agreement with a model taking into account the effect of the exchange interaction on both the bright and dark exciton states as well as the interaction with the magnetic field.

18.
Appl Opt ; 59(23): 7053-7065, 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32788800

RESUMO

The behavior of paint removal with a pulsed laser has been investigated using an Nd:YAG fiber laser. Experimental and theoretical analyses are conducted to reveal the underlying mechanism of the paint removal. The results show that the depth, radius, and volume of the pit formed by a single pulse become larger with increases in the energy density. The ideal parameters for the complete removal of paint have been achieved. During the paint removal, burning occurred over the surface, and the variation in element content has been attributed to the absorption of laser energy. Under the action of the pulsed laser, there was breakage and rearrangement of chemical bonds such as C-C, C-N, and C-O in the molecular chain of the polyacrylate paint coating. Through these analyses, the paint removal mechanism was shown to be based on chemical bond breakage, combustion, and mechanical action provided by the thermal expansion and plasma shock.

19.
Zhonghua Shao Shang Za Zhi ; 36(8): 671-678, 2020 Aug 20.
Artigo em Chinês | MEDLINE | ID: mdl-32829606

RESUMO

Objective: To develop a wireless sensor module for wound temperature and pressure (hereinafter referred to as wireless sensor module), and to carry out related characteristic test and biosafety evaluation. Methods: (1) The structure and working mode of the wireless sensor module were designed. The temperature and humidity sensor welded at one end of the flexible cable and the pressure sensor were simultaneously connected with the printed circuit board, which was welded with the Bluetooth transmitter, microprocessor, and power interface to establish a wireless sensor module. A mobile data receiving application was developed and the monitoring values of the wireless sensor module exposed to the air were read through the Bluetooth function on the smart phone. (2) The temperature of a 35-42 ℃ hot water bag was measured by the wireless sensor module and an infrared thermometer at the same time, and 30 pairs of data were compared with correlation analysis performed. (3) The vacuum sealing drainage material was pasted on the arm of the second author, and the wireless sensor module was placed in the condition of negative pressure. The negative pressure values measured by the wireless sensor module and the negative pressure meter values were recorded at the same time, and 14 pairs of data were compared with correlation analysis performed. (4) The corresponding material extract was prepared by adding 1 mL normal saline per 3 square centimeters surface area of the pressure sensor or flexible cable with temperature and humidity sensor welded respectively. Twenty 6-8 week-old female C57BL/6 mice were weighed before experiment and divided into pressure sensor extract group, flexible cable extract group, mixed extract group, and normal saline group according to the random number table (n=5). The abnormal toxic reactions of mice were observed after intraperitoneal injection of pressure sensor extract, flexible cable with temperature and humidity sensor welded extract, 1∶1 mixed extract of pressure sensor extract and flexible cable with temperature and humidity sensor welded extract, and normal saline for 50 mL/kg in corresponding groups. The body mass of mice was weighed at 24, 48, and 72 hours after injection, and the toxicity of the materials was evaluated comprehensively. (5) Four Japanese big ear white rabbits aged 3-6 months were selected, and there was no limit between male and female. Two regions on the left side of the spine were applied with aseptic gauze as aseptic gauze group, and two areas on the right side of the spine were applied with wireless sensor module as wireless sensor module group. The skin status of each region was evaluated at 1, 12, 24, 48 hours after application, and the score according to the skin irritation score standard was recorded. (6) The corresponding material extract was prepared by adding 1 mL serum-free Dulbecco's modification of Eagle's medium (DMEM) per 1 square centimeter surface area of the pressure sensor or flexible cable with temperature and humidity sensor welded respectively. L-929 fibroblasts were divided into pressure sensor extract group, flexible cable extract group, phenol control group, and medium control group. The corresponding extract was added in the first two groups, the phenol control group was added with 64 g/L phenol, and the medium control group was cultured with serum-free DMEM. The total volumes of the above four groups were all 100 µL. The absorbance values on the 2nd, 4th, 7th day of culture were detected by methyl thiazolyl tetrazolium method to calculate the cell proliferation rate (n=6 at each time point) and to grade the cytotoxicity. Data were statistically analyzed with paired samples t test, Wilcoxon signed rank test, Pearson correlation analysis, Spearman correlation analysis, Mann-Whitney U test, analysis of variance for repeated measurement, analysis of variance for factorial design, one-way analysis of variance, and Bonferroni correction. Results: (1) The smart phone successfully received the air temperature, humidity, and pressure information detected by the wireless sensor module through the Bluetooth function. (2) The temperature of the hot water bag measured by the wireless sensor module was (37.7±1.7) ℃, which was close to (37.7±1.7) ℃ of the infrared thermometer (t=-0.112, P>0.05), and there was a significant positive correlation between them (r=0.996, P<0.01). (3) The negative pressure of arm under negative pressure material measured by the wireless sensor module was -36.7 (-38.8, -27.4) kPa, which was significantly lower than -22.7 (-32.7, -12.5) kPa of negative pressure meter (Z=-3.235, P<0.01), but there was a significant positive correlation between their absolute values (ρ=1.000, P<0.01). (4) There was no abnormal toxic reaction in all groups of rats, and there was no statistically significant difference in body mass among the four groups of mice (F=3.132, P>0.05). (5) The scores of skin irritation in application region of rats in the two groups were similar at 1, 12, 24, 48 hours after application (Z=-1.000, <0.001, -0.620, <0.001, P>0.05). (6) At each time point of culture, compared with that of medium control group, the cell proliferation rate increased significantly in pressure sensor extract group and flexible cable extract group (P<0.01) but decreased significantly in phenol control group (P<0.01). On the 2nd, 4th, 7th day of culture, the cytotoxicity grade of phenol control group was 1, 1, and 2 respectively, and the cytotoxicity grade of each extract group was 0. Conclusions: The wireless sensor module integrates temperature, humidity, and pressure sensors, which can monitor local temperature and pressure and realize the visualization of parameters on the mobile application program. The measurement of temperature is accurate and the pressure measurement results are consistent with the values of the negative pressure meter with good biosafety. It possesses a big value in clinical application and prospects for development.


Assuntos
Drenagem , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Coelhos , Ratos , Temperatura , Vácuo
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