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1.
Exp Cell Res ; 434(2): 113889, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-38113969

RESUMO

The potential protective effect of basic fibroblast growth factor (BFGF) on the cardiovascular system has been proposed previously, however, its effect on calcific aortic valve disease (CAVD) and underlying mechanisms have not been elucidated. The valvular interstitial cell (VIC) were isolated from porcine aortic valve leaflets. To investigate the effect of BFGF on osteogenic differentiation of VIC, the osteogenic induced medium (OIM) and BFGF were added. The protein expression level was detected by Western blot, and apoptosis was determined by flow cytometry. The effect of BFGF on CAVD process in vivo was assessed by a rat CAVD model, which was identified by echocardiography and Alizarin red staining. The expression level of BFGF in the aortic valve and serum were significantly upregulated in CAVD patients compared to control group. In addition, exogenous BFGF injection attenuates CAVD process in vivo. The protein markers of osteogenic differentiation, endoplasmic reticulum stress (ERS), and apoptosis were significantly upregulated by culture with OIM. On the contrary, the aforementioned proteins were suppressed after adding 100 ng/mL of BFGF. Inhibition of PI3K/Akt and ERK1/2 pathways by specific inhibitors abolished the protective effect of BFGF. In conclusion, BFGF could alleviate the VIC calcification by inhibiting ERS-mediated apoptosis, which is partly regulated by activation of the PI3K/Akt and ERK1/2 signaling pathways. BFGF may provide a potential avenue for CAVD therapy.


Assuntos
Valva Aórtica , Fator 2 de Crescimento de Fibroblastos , Humanos , Ratos , Animais , Suínos , Valva Aórtica/metabolismo , Fator 2 de Crescimento de Fibroblastos/farmacologia , Fator 2 de Crescimento de Fibroblastos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Osteogênese , Fosfatidilinositol 3-Quinases/metabolismo , Células Cultivadas , Apoptose
2.
J Clin Monit Comput ; 36(6): 1753-1759, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35426575

RESUMO

Gattinoni's equation, [Formula: see text], now commonly used to calculate the mechanical power (MP) of ventilation. However, it calculates only inspiratory MP. In addition, the inclusion of PEEP in Gattinoni's equation raises debate because PEEP does not produce net displacement or contribute to MP. Measuring the area within the pressure-volume loop accurately reflects the MP received in a whole ventilation cycle and the MP thus obtained is not influenced by PEEP. The MP of 25 invasively ventilated patients were calculated by Gattinoni's equation and measured by integration of the areas within the pressure-volume loops of the ventilation cycles. The MP obtained from both methods were compared. The effects of PEEPs on MP were also evaluated. We found that the MP obtained from both methods were correlated by R2 = 0.75 and 0.66 at PEEP 5 and 10 cmH2O, respectively. The biases of the two methods were 3.13 (2.03 to 4.23) J/min (P < 0.0001) and - 1.23 (- 2.22 to - 0.24) J/min (P = 0.02) at PEEP 5 and 10 cmH2O, respectively. These P values suggested that both methods were significantly incongruent. When the tidal volume used was 6 ml/Kg, the MP by Gattinoni's equation at PEEP 5 and 10 cmH2O were significantly different (4.51 vs 7.21 J/min, P < 0.001), but the MP by PV loop area was not influenced by PEEPs (6.46 vs 6.47 J/min, P = 0.331). Similar results were observed across all tidal volumes. We conclude that the Gattinoni's equation is not accurate in calculating the MP of a whole ventilatory cycle and is significantly influenced by PEEP, which theoretically does not contribute to MP.


Assuntos
Síndrome do Desconforto Respiratório , Humanos , Respiração com Pressão Positiva/métodos , Volume de Ventilação Pulmonar , Pulmão
3.
Pulm Pharmacol Ther ; 49: 134-139, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29474893

RESUMO

INTRODUCTION: The optimal dose of inhaled metered-dose bronchodilators for intubated patients with chronic obstructive pulmonary disease (COPD) is unknown. In this study, we proposed a bronchodilator dosing schedule based on an individual's airway resistance (Raw) and tested its efficacy in reducing Raw. METHODS: A total of 51 newly admitted patients with invasively ventilated COPD were randomly assigned to receive personalized or fixed bronchodilator dosing. Personal target Raw was defined by measuring each individual's Raw after maximal pharmacologic bronchodilatation. Thereafter, Raw was measured every 8 h until the 28th day. Patients in the fixed-dosing group received only predetermined doses. Additional doses of bronchodilators were given to patients in the personalized-dosing group when the measured Raw exceeded their target Raw. RESULTS: The median daily doses of salmeterol/fluticasone were 9.2 (personalized-dosing) vs 7.6 (fixed-dosing) puffs (P < 0.001). The relative deviation of Raw from the personal target was expressed as (measured Raw - target Raw)/target Raw. The experimental group showed a smaller relative Raw deviation than the control group (0.09 ±â€¯0.10 vs 0.44 ±â€¯0.11, P = 0.02). There were no differences between the two groups in terms of ventilator-free days from day 1 to day 28, number of episodes of nosocomial pneumonia, total number of puffs of rescue bronchodilator, number of drug-related adverse effects or mortality rate at day 180. CONCLUSION: Personalized dosing of inhaled bronchodilator administered to invasively ventilated COPD patients can produce a better reduction in Raw. Further studies with larger sample size are required to verify the conclusion of this pilot study.


Assuntos
Resistência das Vias Respiratórias/efeitos dos fármacos , Broncodilatadores/administração & dosagem , Medicina de Precisão/métodos , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Administração por Inalação , Idoso , Idoso de 80 Anos ou mais , Relação Dose-Resposta a Droga , Feminino , Combinação Fluticasona-Salmeterol/administração & dosagem , Humanos , Masculino , Inaladores Dosimetrados , Pessoa de Meia-Idade , Projetos Piloto , Doença Pulmonar Obstrutiva Crônica/fisiopatologia
4.
Shock ; 61(1): 68-75, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38010031

RESUMO

ABSTRACT: Background: Intermediate-risk pulmonary embolism (PE) patients in the intensive care unit (ICU) are at a higher risk of hemodynamic deterioration than those in the general ward. This study aimed to construct a machine learning (ML) model to accurately identify the tendency for hemodynamic deterioration in the ICU patients with intermediate-risk PE. Method: A total of 704 intermediate-risk PE patients from the MIMIC-IV database were retrospectively collected. The primary outcome was defined as hemodynamic deterioration occurring within 30 days after admission to ICU. Four ML algorithms were used to construct models on the basis of all variables from MIMIC IV database with missing values less than 20%. The extreme gradient boosting (XGBoost) model was further simplified for clinical application. The performance of the ML models was evaluated by using the receiver operating characteristic curve, calibration plots, and decision curve analysis. Predictive performance of simplified XGBoost was compared with the simplified Pulmonary Embolism Severity Index score. SHapley Additive explanation (SHAP) was performed on a simplified XGBoost model to calculate the contribution and impact of each feature on the predicted outcome and presents it visually. Results: Among the 704 intermediate-risk PE patients included in this study, 120 patients experienced hemodynamic deterioration within 30 days after admission to the ICU. Simplified XGBoost model demonstrated the best predictive performance with an area under the curve of 0.866 (95% confidence interval, 0.800-0.925), and after recalibrated by isotonic regression, the area under the curve improved to 0.885 (95% confidence interval, 0.822-0.935). Based on the simplified XGBoost model, a web app was developed to identify the tendency for hemodynamic deterioration in ICU patients with intermediate-risk PE. Conclusion: A simplified XGBoost model can accurately predict the occurrence of hemodynamic deterioration for intermediate-risk PE patients in the ICU, assisting clinical workers in providing more personalized management for PE patients in the ICU.


Assuntos
Unidades de Terapia Intensiva , Embolia Pulmonar , Humanos , Estudos Retrospectivos , Hemodinâmica , Aprendizado de Máquina , Embolia Pulmonar/diagnóstico
5.
Respiration ; 85(5): 367-74, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23207346

RESUMO

BACKGROUND: The usual management of ventilator-associated pneumothorax (VPX) is tube thoracostomy. However, this recommendation is based on tradition rather than on solid evidence. Although it has been applied successfully to other types of pneumothoraces, observation has not been used in the management of VPX. OBJECTIVES: In this study, we investigated whether observation is a valid treatment strategy for VPX. METHODS: We retrospectively analyzed data of 471 patients with VPX (2003-2010) and found that 27 did not receive tube thoracostomy. Most of those patients (89%) had documented do-not-resuscitate orders and had refused tube thoracostomy. For comparison, 54 patients with tube thoracostomy, matched by age and do-not-resuscitate status, were chosen as controls. Among patients without tube thoracostomy, we compared attribute differences between those recovered and those not recovered. RESULTS: Thirteen patients (48%) without tube thoracostomy experienced spontaneous recovery of their pneumothoraces. This rate of chest tube-free recovery was higher than that of patients with tube thoracostomy (48 vs. 17%; p = 0.003). The patients did not differ in in-hospital mortality rate, time to ventilator discontinuation or survival. By univariate logistic regression, spontaneous recovery was associated with VPX caused by needle puncture, lack of respiratory distress, large tidal volume and low oxygen requirement following pneumothorax, as well as by physician recommendation against intubation. CONCLUSION: Observation under physician surveillance is an effective option of managing many VPXs, especially those caused by needle puncture, when patients are not in respiratory distress or when patients have acceptable tidal volumes and oxygen requirements following pneumothorax.


Assuntos
Pneumotórax , Punções/efeitos adversos , Respiração Artificial/efeitos adversos , Toracostomia , Idoso , Idoso de 80 Anos ou mais , Tubos Torácicos , Feminino , Humanos , Hipóxia/etiologia , Masculino , Avaliação de Processos e Resultados em Cuidados de Saúde , Pneumotórax/complicações , Pneumotórax/etiologia , Pneumotórax/fisiopatologia , Pneumotórax/cirurgia , Recuperação de Função Fisiológica , Remissão Espontânea , Ordens quanto à Conduta (Ética Médica) , Estudos Retrospectivos , Taiwan , Toracostomia/efeitos adversos , Toracostomia/instrumentação , Toracostomia/métodos , Volume de Ventilação Pulmonar , Resultado do Tratamento
6.
Nanomaterials (Basel) ; 13(4)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36839057

RESUMO

In this study, the bipolar switching properties and electrical conduction behaviors of the ITO thin films RRAM devices were investigated. For the transparent RRAM devices structure, indium tin oxide thin films were deposited by using the RF magnetron sputtering method on the ITO/glass substrate. For the ITO/ITOX/ITO/glass (MIM) structure, an indium tin oxide thin film top electrode was prepared to form the transparent RRAM devices. From the experimental results, the 102 On/Off memory ratio and bipolar switching cycling properties for set/reset stable states were found and discussed. All transparent RRAM devices exhibited the obvious memory window and low set voltage for the switching times of 120 cycles. The electrical transport mechanisms were dominated by the ohmic contact and space charge limit conduction (SCLC) models for set and reset states. Finally, the transmittances properties of the transparent ITO/ITOX/ITO RRAM devices for the different oxygen growth procedures were about 90% according to the UV-Vis spectrophotometer for the visible wavelength range.

7.
Nanomaterials (Basel) ; 13(19)2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37836326

RESUMO

Copper-doped zinc oxide films (Zn1-xCuxO) (x = 0, 2%, 4%, 6%) were fabricated on conductive substrates using the sol-gel process. The crystal structure, optical and resistive switching properties of Zn1-xCuxO films are studied and discussed. RRAM is made using Zn1-xCuxO as the resistive layer. The results show that the (002) peak intensity and grain size of Zn1-xCuxOfilms increase from 0 to 6%. In addition, PL spectroscopy shows that the oxygen vacancy defect density of Zn1-xCuxO films also increases with the increase in Cu. The improved resistive switching performance of the RRAM device can be attributed to the formation of conductive filaments and the destruction of more oxygen vacancies in the Zn1-xCuxO film. Consequently, the RRAM device exhibits a higher low resistance state to high resistance state ratio and an HRS state of higher resistance value.

8.
Nanomaterials (Basel) ; 13(15)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37570498

RESUMO

Activation energy, bipolar resistance switching behavior, and the electrical conduction transport properties of ITOX:SiO2 thin film resistive random access memory (RRAM) devices were observed and discussed. The ITOX:SiO2 thin films were prepared using a co-sputtering deposition method on the TiN/Si substrate. For the RRAM device structure fabrication, an Al/ITOX:SiO2/TiN/Si structure was prepared by using aluminum for the top electrode and a TiN material for the bottom electrode. In addition, grain growth, defect reduction, and RRAM device performance of the ITOX:SiO2 thin film for the various oxygen gas flow conditions were observed and described. Based on the I-V curve measurements of the RRAM devices, the turn on-off ratio and the bipolar resistance switching properties of the Al/ITOX:SiO2/TiN/Si RRAM devices in the set and reset states were also obtained. At low operating voltages and high resistance values, the conductance mechanism exhibits hopping conduction mechanisms for set states. Moreover, at high operating voltages, the conductance mechanism behaves as an ohmic conduction current mechanism. Finally, the Al/ITOX:SiO2/TiN/Si RRAM devices demonstrated memory window properties, bipolar resistance switching behavior, and nonvolatile characteristics for next-generation nonvolatile memory applications.

9.
Nanomaterials (Basel) ; 13(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36616108

RESUMO

In the reset state, the decay reaction mechanism and bipolar switching properties of vanadium oxide thin film RRAM devices for LRS/HRS are investigated and discussed here. To discover the properties of I-V switching curves, the first order rate law behaviors of the reset state between the resistant variety properties and the reaction time were observed. To verify the decay reaction mechanism in the reset state, vanadium oxide thin films from RRAM devices were measured by different constant voltage sampling and exhibited the same decay reaction rate constant. Finally, the electrical conduction transfer mechanism and metallic filament forming model described by I-V switching properties of the RRAM devices were proven and investigated.

11.
Indian J Nucl Med ; 36(4): 412-421, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35125759

RESUMO

BACKGROUND: Optimal peptide concentration in treatment with 177Lu-DOTATOC/DOTATATE is a matter of debate. Most of the studies with peptide receptor radionuclide therapy mention peptide dose ranging between 100 and 250 µg. The aim of this is to identify possible differences in radiation-absorbed doses (D/Gy) to tumor and kidney as a function of the peptide mass dose in order to identify the most suitable peptide dose for treatment. The therapeutic index (Dtumor/Dkidneys) was assessed as a key parameter for the treatment response. MATERIALS AND METHODS: Five patients with metastasized Grade 1 to Grade 2 neuroendocrine tumor were analyzed in this study. Patients (n = 4) received two cycles of treatment with intravenously injected 177Lu-DOTATOC containing peptide mass doses of 200 µg and 90 µg, alternatively; one patient was treated with 90 µg peptide mass in both the therapy cycles. Whole-body (head to mid-thigh) three-dimensional single-photon emission computerized tomography (3D SPECT)/CT images were acquired at 1, 4, 24, 48, and 72 h following the injection of 177Lu-DOTATOC. Attenuation correction for 3D SPECT images was performed using CT data acquired and fused with the SPECT data (SPECT/CT). RESULTS: Overall, 28 target lesions (liver n = 17, lung n = 4, lymph nodes n = 1, and bone n = 2) were analyzed after 1st and 2nd therapy cycles. Tumor normalized absorbed doses varied by a factor of 74 between 0.35 and 26 mGy/MBq. Averaged over all patients, a higher normalized mean tumor dose (10.51 mGy/MBq) was achieved for a peptide dose of 200 µg compared to 90 µg (4.58 mGy/MBq). Kidneys doses varied by a factor of up to 4 between patients (0.25-1.0 mGy/MBq) (independent of dose cycle and peptide dose) and by a factor of up to 2 between dose cycles. The mean kidney dose was 13.7% higher for the 90 µg peptide dose compared to 200 µg. Given the higher tumor dose, the mean therapeutic index of a 200 µg mass dose was considerably higher (16.95), compared to a 90 µg mass dose (9.63). This coincided with the observation, that lesion volume reduction was more pronounced after an initial treatment with a 200 µg mass dose. Biologically effective dose was only 5. 1%-19.3% higher than the absorbed dose for individual dose cycles. CONCLUSIONS: Higher peptide dose of 200 µg appears to be more suitable than 90 µg in terms of tumor dose, kidney dose, and therapeutic index for treatment with 177Lu-DOTATOC.

12.
Diagnostics (Basel) ; 11(4)2021 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-33916745

RESUMO

This study investigated the usefulness of ventilator parameters in the prediction of development and outcome of acute respiratory distress syndrome (ARDS) in postoperative patients with esophageal or lung cancer on admission to the surgical intensive care unit (SICU). A total of 32 post-operative patients with lung or esophageal cancer from SICU in a tertiary medical center were retrospectively analyzed. The study patients were divided into an ARDS group (n = 21) and a non-ARDS group (n = 11). The ARDS group contained the postoperative patients who developed ARDS after lung or esophageal cancer surgery. The ventilator variables were analyzed in this study. Principal component analysis (PCA) was performed to reduce the correlated ventilator variables to a small set of variables. The top three ventilator variables with large coefficients, as determined by PCA, were considered as sensitive variables and included in the analysis model based on the rule of 10 events per variable. Firth logistic regression with selective stepwise elimination procedure was performed to identify the most important predictors of morbidity and mortality in patients with ARDS. Ventilator parameters, including rapid shallow breath index during mechanical ventilation (RSBIv), rate pressure product of ventilation (RPPv), rate pressure volume index (RPVI), mechanical work (MW), and inspiration to expiration time ratio (IER), were analyzed in this study. It was found that the ARDS patients had significantly greater respiratory rate (RR), airway resistance (Raw), RSBIv, RPPv, RPVI, positive end-expiratory pressure (PEEP), and IER and significantly lower respiratory interval (RI), expiration time (Te), flow rate (V˙), tidal volume (VT), dynamic compliance (Cdyn), mechanical work of ventilation (MW), and MW/IER ratio than the non-ARDS patients. The non-survivors of ARDS had significantly greater peak inspiratory pressure above PEEP (PIP), RSBIv, RPPv, and RPVI than the survivors of ARDS. By using PCA, the MW/IER was found to be the most important predictor of the development of ARDS, and both RPPv and RPVI were significant predictors of mortality in patients with ARDS. In conclusion, some ventilator parameters, such as RPPv, RPVI, and MW/IER defined in this study, can be derived from ventilator readings and used to predict the development and outcome of ARDS in mechanically ventilated patients on admission to the SICU.

13.
Sci Rep ; 11(1): 8565, 2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33883566

RESUMO

Cryptococcal meningitis (CM) is the most fatal adult meningitis in patients with human immunodeficiency virus (HIV). There is no conclusive evidence for the superiority of 1-week amphotericin B deoxycholate (AmphB) + flucytosine (5-FC) regimen over other antifungals in the management of HIV patients with CM (HIV-CM patients). We aimed to evaluate the differences in efficacy and tolerability of different antifungal agents in HIV-CM patients by conducting a current network meta-analysis NMA. Overall, 19 randomized controlled trials were included with 2642 participants. A regimen indicated a possibly lower early mortality rate, namely, AmphB + 5-FC + Azole (OR = 1.1E-12, 95% CIs = 1.3E-41 to 0.06) comparing to AmphB + 5-FC. The current NMA provides evidence that AmphB + 5-FC + Azole are superior to all the investigated treatments for induction regimen in HIV-CM patients.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Ácido Desoxicólico/uso terapêutico , Flucitosina/uso terapêutico , Meningite Criptocócica/tratamento farmacológico , Anfotericina B/administração & dosagem , Antifúngicos/administração & dosagem , Ácido Desoxicólico/administração & dosagem , Combinação de Medicamentos , Flucitosina/administração & dosagem , Humanos , Quimioterapia de Indução/métodos , Resultado do Tratamento
14.
Biomed Res Int ; 2020: 8085106, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32509871

RESUMO

Diabetes mellitus (DM) and tuberculosis (TB) are major public health and economic burdens. DM increases Mycobacterium tuberculosis (M.tb) infection rates and treatment durations. This study evaluated the relationship between five classes of oral DM medications and TB infection risk in DM patients. We used longitudinal records from the Taiwan Longitudinal Health Insurance Research Database. DM patients were identified using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) code 250 and A code A181. TB patients were identified using ICD-9-CM code 010.x-017.x. Oral DM medications were divided into five classes: sulfonylureas, biguanides, meglitinides, α-glucosidase inhibitors (AGIs), and thiazolidinediones. Users were classified as nonusers, low-concentration users, and high-concentration users. The incidence rate ratio (IRR) was derived using multivariate Poisson regression to calculate the relative risk of TB infection. DM patients using low- and high-concentration AGIs had significantly lower TB infection risks compared with nonusers. The IRRs of the sulfonylureas and AGI users were [CI] 0.693-0.948) and (95% CI 0.651-0.995), respectively. The other four classes of medications exhibited no significant effect on TB infection risk in DM patients. Furthermore, DM patients using high-concentration AGIs had a significantly lower TB infection risk compared with those using low-concentration AGIs (IRR 0.918, 95% CI: 0.854-0.987). We noted a dose-response relationship in the effects of DM medications on TB risk. Accordingly, we suggest that DM patients use AGIs to benefit from their protective effect on TB infection risk.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores de Glicosídeo Hidrolases/uso terapêutico , Tuberculose/epidemiologia , Adulto , Idoso , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Tuberculose/complicações , Tuberculose/prevenção & controle , Adulto Jovem
15.
Emerg Infect Dis ; 15(3): 402-7, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19239752

RESUMO

From January 2004 through June 2008, surveillance of dead wild birds in Hong Kong, People's Republic of China, periodically detected highly pathogenic avian influenza (HPAI) viruses (H5N1) in individual birds from different species. During this period, no viruses of subtype H5N1 were detected in poultry on farms and in markets in Hong Kong despite intensive surveillance. Thus, these findings in wild birds demonstrate the potential for wild birds to disseminate HPAI viruses (H5N1) to areas otherwise free from the viruses. Genetic and antigenic characterization of 47 HPAI (H5N1) viruses isolated from dead wild birds in Hong Kong showed that these isolates belonged to 2 antigenically distinct virus groups: clades 2.3.4 and 2.3.2. Although research has shown that clade 2.3.4 viruses are established in poultry in Asia, the emergence of clade 2.3.2 viruses in nonpasserine birds from Hong Kong, Japan, and Russia raises the possibility that this virus lineage may have become established in wild birds.


Assuntos
Animais Selvagens/virologia , Doenças das Aves , Aves/virologia , Virus da Influenza A Subtipo H5N1/classificação , Influenza Aviária , Animais , Doenças das Aves/epidemiologia , Doenças das Aves/virologia , Testes de Inibição da Hemaglutinação , Hong Kong/epidemiologia , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/isolamento & purificação , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
16.
Bioresour Technol ; 99(7): 2436-41, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-17604621

RESUMO

The present work elucidates environmental friendly removal process of heavy metals by using biomass waste and natural product. The process consists of the following three steps: (1) leaching of all metals including heavy metals by dilute sulfuric acid, (2) removal of turbid organic materials from the leach liquor by means of coagulation using astringent persimmon extract enriched with persimmon tannin leaving all heavy metal ions in the leach liquor and (3) adsorptive removal of heavy metals by means of adsorption onto the gel prepared from apple waste. The operational conditions at these three steps were discussed in detail, among which the pH adjustment is the key factor; i.e. the lower the pHs the higher the efficiency of the leaching, while reverse was the case for the adsorption.


Assuntos
Ração Animal , Fertilizantes , Metais Pesados/isolamento & purificação , Frutos do Mar , Adsorção , Animais
17.
Materials (Basel) ; 11(2)2018 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-29364832

RESUMO

By the conventional solid state reaction method, a small amount of lithium fluoride (LiF) was used as the sintering promoter to improve the sintering and piezoelectric characteristics of (Ba0.95Ca0.05)(Ti0.93Sn0.07)O3 (BCTS) lead-free piezoceramic sheets. Using X-ray diffraction (XRD) and a scanning electron microscope (SEM), the inferences of the crystalline and surface microstructures were obtained and analyzed. Then, the impedance analyzer and d33-meter were used to measure the dielectric and piezoelectric characteristics. In this study, the optimum sintering temperature of the BCTS sheets decreased from 1450 °C to 1390 °C due to LiF doping. For the 0.07 wt % LiF-doped BCTS sheets sintered at 1390 °C, the piezoelectric constant (d33) is 413 pC/N, the electric-mechanical coupling coefficient (kp) is 47.5%, the dielectric loss (tan δ) is 3.9%, and the dielectric constant (εr) is 8100, which are all close to or even better than that of the pure undoped BCTS ceramics. The Curie temperature also improved, from 85 °C for pure BCTS to 140 °C for BCTS-0.07 LiF sheets. Furthermore, by using the vibration system and fixing 1.5 g tip mass at the end of the sheets, as the vibration frequency is 20 Hz, the proposed piezoelectric ceramic sheets also reveal a good energy harvesting performance at the maximum output peak voltage of 4.6 V, which is large enough and can be applied in modern low-power electronic products.

18.
Eur J Heart Fail ; 9(4): 343-51, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17251059

RESUMO

BACKGROUND: Previous studies suggest that vascular endothelial growth factor (VEGF) is a regulator of naturally occurring angiogenesis. However, whether VEGF plays a role in cardiomyocyte apoptosis is not known. AIM: To investigate the effects of intramyocardial injection of VEGF165 cDNA on cardiac performance and cardiomyocyte apoptosis in a rat model of acute myocardial infarction. METHODS: Forty male Sprague-Dawley rats underwent left coronary artery ligation and were randomised to receive VEGF165 cDNA (treated group) or pcDNA3.1 (control), injected directly into the border zone of the ischaemic myocardium. Twenty rats underwent thoracotomy and injection of pcDNA3.1, without coronary ligation (sham group). Haemodynamic and apoptotic parameters were measured two weeks after injection. RESULTS: Three sham, eight control, and five treated animals died. Haemodynamic parameters and microvessel counts in the treated group were significantly better than in the control (P<0.05 to 0.01). Apoptotic index in the treated group was less than in the control (P<0.01). Caspase-3 activation and mitochondrial cytochrome c release in the treated group were also lower than in the control (P<0.01). VEGF165 cDNA treatment significantly inhibited p53, Fas, Bax, and increased VEGF and Bcl-2 expression in the myocardium. CONCLUSION: Intramyocardial injection of VEGF165 cDNA significantly improved cardiac performance, stimulated angiogenesis and reduced cardiomyocyte apoptosis, in a rat model of acute myocardial infarction.


Assuntos
Apoptose , Insuficiência Cardíaca/etiologia , Células Musculares , Miocárdio/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Animais , DNA Complementar , Expressão Gênica , Terapia Genética , Insuficiência Cardíaca/fisiopatologia , Imuno-Histoquímica , Masculino , Infarto do Miocárdio , Isquemia Miocárdica , Miocárdio/citologia , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular/metabolismo
19.
Artigo em Inglês | MEDLINE | ID: mdl-17941379

RESUMO

In this study, the Ba(Zr0.1Ti0.9)O3 (BZ1T9) thin films have been well deposited on the Pt/Ti/SiO2/Si substrate. The optimum radio frequency (RF) deposition parameters are developed, and the BZ1T9 thin films deposition at the optimum parameters have the maximum capacitance and dielectric constant of 4.4 nF and 190. As the applied voltage is increased to 8 V, the remnant polarization and coercive field of BZ1T9 thin films are about 4.5 microC/cm2 and 80 kV/cm. The counterclockwise current hysteresis and memory window of n-channel thin-film transistor property are observed, and that can be used to indicate the switching of ferroelectric polarization of BZ1T9 thin films. One-transistor-capacitor (1TC) structure of BZ1T9 ferroelectric random access memory device using bottom-gate amorphous silicon thin-film transistor was desirable because of the smaller size and better sensitivity. The BZ1T9 ferroelectric RAM devices with channel width = 40 microm and channel length = 8 microm has been successfully fabricated and the ID-VG transfer characteristics also are investigated in this study.


Assuntos
Compostos de Bário/química , Dispositivos de Armazenamento em Computador , Capacitância Elétrica , Nanoestruturas/química , Transistores Eletrônicos , Eletroquímica/instrumentação , Eletroquímica/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Membranas Artificiais , Volatilização
20.
Chin J Traumatol ; 10(5): 279-83, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17919365

RESUMO

OBJECTIVE: To investigate the application of damage control surgery in treatment of patients with severe thoracic and abdominal injuries. METHODS: A retrospective study was done on 37 patients with severe thoracic and abdominal injuries who underwent damage control surgery from January 2000 to October 2006 in our department. There were 8 cases of polytrauma (with thoracic injury most commonly seen), 21 of polytrauma (with abdominal injury most commonly seen) and 8 of single abdominal trauma. Main organ damage included smashed hepatic injuries in 17 cases, posterior hepatic veins injuries in 8,pancreaticoduodenal injuries in 7, epidural or subdural hemorrhage in 4, contusion and laceration of brain in 5, severe lung and bronchus injuries in 4, pelvis and one smashed lower limb wound in 3 and pelvic fractures and retroperitoneal hemorrhage in 6. Injury severity score (ISS) was 28-45 scores (38.4 scores on average), abbreviated injury scale (AIS) > or = 4.13. The patients underwent arteriography and arterial embolization including arteria hepatica embolization in 4 patients, arteria renalis embolization in 2 and pelvic arteria retroperitoneal embolization in 7. Once abbreviated operation finished, the patients were sent to ICU for resuscitation. Twenty-four cases underwent definitive operation within 48 hours after initial operation, 5 underwent definitive operation within 72 hours after initial operation, 2 cases underwent definitive operation postponed to 96 hours after initial operation for secondary operation to control bleeding because of abdominal cavity hemorrhea. Two cases underwent urgent laparotomy and decompression because of abdominal compartment syndrome and 2 cases underwent secondary operation because of intestinal fistulae (1 case of small intestinal fistula and 1 colon fistula) and gangrene of gallbladder. RESULTS: A total of 28 patients survived, with a survival rate of 75.68%, and 9 died (4 died within 24 hours and 5 died 3-9 days after injury). The trauma deaths at the early stage were caused by severe primary injuries resulting in failure of respiration and circulation, while mortality at the later stage was caused by multiple organ failure. CONCLUSIONS: Damage control surgery is important for the treatment against severe thoracic and abdominal injuries. It is suggested that the surgeon should select the reasonable auxiliary examination before operation, and take the proper time to perform damage control and definitive surgery.


Assuntos
Traumatismos Abdominais/cirurgia , Traumatismos Torácicos/cirurgia , Traumatismos Abdominais/diagnóstico , Adulto , Idoso , Angiografia Digital , Embolização Terapêutica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ressuscitação , Estudos Retrospectivos , Traumatismos Torácicos/diagnóstico
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