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2.
Sci Rep ; 13(1): 15910, 2023 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-37741874

RESUMO

This study evaluated the aerosol exposure risks while using common noninvasive oxygenation devices. A simulated mannequin was designed to breathe at a minute ventilation of 20 L/min and used the following oxygen-therapy devices: nasal cannula oxygenation (NCO) at 4 and 15 L/min, nonrebreathing mask (NRM) at 15 L/min, simple mask at 6 L/min, combination of NCO at 15 L/min and NRM at 15 L/min, high-flow nasal cannula (HFNC) at 50 L/min, and flush rate NRM. Two-dimension of the dispersion distance and the aerosol concentrations were measured at head, trunk, and foot around the mannequin for over 10 min. HFNC and flush-rate NRM yielded the longest dispersion distance and highest aerosol concentrations over the three sites of the mannequin than the other oxygenation devices and should use with caution. For flow rates of < 15 L/min, oxygenation devices with mask-like effects, such as NRM or NCO with NRM, decreased aerosol dispersion more effectively than NCO alone or a simple mask. In the upright position, the foot area exhibited the highest aerosol concentration regardless of the oxygenation device than the head-trunk areas of the mannequin. Healthcare workers should be alert even at the foot side of the patient while administering oxygenation therapy.


Assuntos
Oxigenoterapia , Fumaça , Humanos , Aerossóis , Oxigenoterapia/métodos , Pulmão , Administração por Inalação
3.
Sci Rep ; 13(1): 12552, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37532861

RESUMO

To evaluate aerosol exposure risk and prevention strategies during bystander, pre-hospital, and inpatient cardiopulmonary resuscitation (CPR). This study compared hands-only CPR, CPR with a surgical or N95 mask, and CPR with a non-rebreather mask at 15 L/min. 30:2 compression-ventilation ratio CPR was tested with face-mask ventilation (FMV), FMV with a high efficiency particulate air (HEPA) filter; supraglottic airway (SGA), SGA with a surgical mask, SGA with a HEPA filter, or SGA with both. Continuous CPR was tested with an endotracheal tube (ET), ET with a surgical mask, a HEPA filter, or both. Aerosol concentration at the head, trunk, and feet of the mannequin were measured to evaluate exposure to CPR personnel. Hands-only CPR with a surgical or N95 face mask coverings and ET tube ventilation CPR with filters showed the lowest aerosol exposure among all study groups, including CPR with NRM oxygenation, FMV, and SGA ventilation. NRM had a mask effect and reduced aerosol exposure at the head, trunk, and feet of the mannequin. FMV with filters during 30:2 CPR reduced aerosol exposure at the head and trunk, but increased at the feet of the mannequin. A tightly-sealed SGA when used with a HEPA filter, reduced aerosol exposure by 21.00-63.14% compared with a loose-fitting one. Hands-only CPR with a proper fit surgical or N95 face mask coverings is as safe as ET tube ventilation CPR with filters, compared with CPR with NRM, FMV, and SGA. FMV or tight-sealed SGA ventilation with filters prolonged the duration to achieve estimated infective dose of SARS-CoV-2 2.4-2.5 times longer than hands-on CPR only. However, a loose-fitting SGA is not protective at all to chest compressor or health workers standing at the foot side of the victim, so should be used with caution even when using with HEPA filters.


Assuntos
COVID-19 , Reanimação Cardiopulmonar , Humanos , Manequins , Pacientes Internados , COVID-19/prevenção & controle , SARS-CoV-2 , Aerossóis e Gotículas Respiratórios , Intubação Intratraqueal , Hospitais
4.
Ann Emerg Med ; 80(1): 22-34, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35469678

RESUMO

STUDY OBJECTIVE: To evaluate aerosol dispersion and exposure risk during oxygenation therapy among health care personnel. METHODS: This study compared the aerosol dispersion effect produced through continuous positive airway pressure (CPAP), bilevel positive airway pressure (BiPAP), BiPAP with face coverings, a high-flow nasal cannula (HFNC) with face coverings, nasal cannula oxygenation (NCO) at 15 L/min with face coverings, nonrebreather mask (NRM), and ventilator-assisted preoxygenation (VAPOX) during oxygenation therapy at a minute ventilation of 10 L/min and 20 L/min. The length and width of aerosol dispersion were recorded, and aerosol concentrations were then detected at a mannequin's head, trunk, and feet. RESULTS: The average length dispersion distance of CPAP was 47.12 cm (SD, 12.56 cm), of BiPAP was 100.13 cm (SD, 6.03 cm), of BiPAP with face coverings was 62.20 cm (SD, 8.46 cm), of HFNC with face coverings was 67.09 cm (SD, 12.74 cm); of NCO with face coverings was 85.55 cm (SD, 7.28 cm); and of NRM was 63.08 cm (SD, 15.33 cm); VAPOX showed no visible dispersion. The aerosol concentrations at the feet under CPAP and at the head under BiPAP were significantly higher than those observed without an oxygen device. Compared with no oxygen device, the aerosol concentration with HFNC was higher at the mannequin's head, trunk, and feet; whereas it was lower with VAPOX and NRM. Moreover, when translated to the number of virus particles required to infect medical personnel (Nf), VAPOX took more time to achieve Nf than other devices. CONCLUSION: Strong flow from the oxygenation devices resulted in increased aerosol concentrations. CPAP at the feet side, BiPAP at the head side, HFNC, and NCO with face coverings significantly increase aerosol exposure and should be used with caution. Aerosol concentrations at all positions were lower with NRM and VAPOX.


Assuntos
Cânula , Ventilação não Invasiva , Aerossóis , Pressão Positiva Contínua nas Vias Aéreas , Humanos , Oxigênio , Oxigenoterapia/métodos , Ventiladores Mecânicos
5.
Sensors (Basel) ; 22(1)2022 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-35009870

RESUMO

Oxyhemoglobin saturation by pulse oximetry (SpO2) has always played an important role in the diagnosis of symptoms. Considering that the traditional SpO2 measurement has a certain error due to the number of wavelengths and the algorithm and the wider application of machine learning and spectrum combination, we propose to use 12-wavelength spectral absorption measurement to improve the accuracy of SpO2 measurement. To investigate the multiple spectral regions for deep learning for SpO2 measurement, three datasets for training and verification were built, which were constructed over the spectra of first region, second region, and full region and their sub-regions, respectively. For each region under the procedures of optimization of our model, a thorough of investigation of hyperparameters is proceeded. Additionally, data augmentation is preformed to expand dataset with added noise randomly, increasing the diversity of data and improving the generalization of the neural network. After that, the established dataset is input to a one dimensional convolution neural network (1D-CNN) to obtain a measurement model of SpO2. In order to enhance the model accuracy, GridSearchCV and Bayesian optimization are applied to optimize the hyperparameters. The optimal accuracies of proposed model optimized by GridSearchCV and Bayesian Optimization is 89.3% and 99.4%, respectively, and trained with the dataset at the spectral region of six wavelengths including 650 nm, 680 nm, 730 nm, 760 nm, 810 nm, 860 nm. The total relative error of the best model is only 0.46%, optimized by Bayesian optimization. Although the spectral measurement with more features can improve the resolution ability of the neural network, the results reveal that the training with the dataset of the shorter six wavelength is redundant. This analysis shows that it is very important to construct an effective 1D-CNN model area for spectral measurement using the appropriate spectral ranges and number of wavelengths. It shows that our proposed 1D-CNN model gives a new and feasible approach to measure SpO2 based on multi-wavelength.


Assuntos
Aprendizado Profundo , Teorema de Bayes , Aprendizado de Máquina , Redes Neurais de Computação , Oximetria
6.
Materials (Basel) ; 14(16)2021 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-34442969

RESUMO

In this study, we submit a complex set of in-situ data collected by optical emission spectroscopy (OES) during the process of aluminum nitride (AlN) thin film. Changing the sputtering power and nitrogen(N2) flow rate, AlN film was deposited on Si substrate using a superior sputtering with a pulsed direct current (DC) method. The correlation between OES data and deposited film residual stress (tensile vs. compressive) associated with crystalline status by X-ray diffraction spectroscopy (XRD), scanning electron microscope (SEM), and transmission electron microscope (TEM) measurements were investigated and established throughout the machine learning exercise. An important answer to know is whether the stress of the processing film is compressive or tensile. To answer this question, we can access as many optical spectra data as we need, record the data to generate a library, and exploit principal component analysis (PCA) to reduce complexity from complex data. After preprocessing through PCA, we demonstrated that we could apply standard artificial neural networks (ANNs), and we could obtain a machine learning classification method to distinguish the stress types of the AlN thin films obtained by analyzing XRD results and correlating with TEM microstructures. Combining PCA with ANNs, an accurate method for in-situ stress prediction and classification was created to solve the semiconductor process problems related to film property on deposited films more efficiently. Therefore, methods for machine learning-assisted classification can be further extended and applied to other semiconductors or related research of interest in the future.

7.
Plant Dis ; 105(12): 3858-3868, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34181437

RESUMO

Rice blast is a serious threat to global rice production. Large-scale and long-term cultivation of rice varieties with a single blast resistance gene usually leads to breakdown of resistance. To effectively control rice blast in Taiwan, marker-assisted backcrossing was conducted to develop monogenic lines carrying different blast resistance genes in the genetic background of an elite japonica rice cultivar, Kaohsiung 145 (KH145). Eleven International Rice Research Institute (IRRI)-bred blast-resistant lines (IRBLs) showing broad-spectrum resistance to local Pyricularia oryzae isolates were used as resistance donors. Sequencing analysis revealed that the recurrent parent, KH145, does not carry known resistance alleles at the target Pi2/9, Pik, Pita, and Ptr loci. For each IRBL × KH145 cross, we screened 21 to 370 (average of 108) plants per generation from the BC1F1 to BC3F1/BC4F1 generation. A total of 1,499 BC3F2/BC4F2 lines carrying homozygous resistance alleles were selected and self-crossed for four to six successive generations. The derived lines were also evaluated for background genotype using genotyping by sequencing, for blast resistance under artificial inoculation and natural infection conditions, and for agronomic performance in multiple field trials. In Chiayi and Taitung blast nurseries in 2018 to 2020, Pi2, Pi9, and Ptr conferred high resistance, Pi20 and Pik-h moderate resistance, and Pi1, Pi7, Pik-p, and Pik susceptibility to leaf blast; only Pi2, Pi9, and Ptr conferred effective resistance against panicle blast. The monogenic lines showed agronomic traits, yield, and grain quality similar to those of KH145, suggesting the potential of growing a mixture of lines to achieve durable resistance in the field.


Assuntos
Resistência à Doença/genética , Magnaporthe , Oryza , Doenças das Plantas , Genótipo , Oryza/genética , Oryza/microbiologia , Melhoramento Vegetal , Doenças das Plantas/genética , Doenças das Plantas/microbiologia
8.
PLoS One ; 16(4): e0250213, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33882091

RESUMO

PURPOSE: To investigate the effectiveness of aerosol clearance using an aerosol box, aerosol bag, wall suction, and a high-efficiency particulate air (HEPA) filter evacuator to prevent aerosol transmission. METHODS: The flow field was visualized using three protective device settings (an aerosol box, and an aerosol bag with and without sealed working channels) and four suction settings (no suction, wall suction, and a HEPA filter evacuator at flow rates of 415 liters per minute [LPM] and 530 LPM). All 12 subgroups were compared with a no intervention group. The primary outcome, aerosol concentration, was measured at the head, trunk, and foot of a mannequin. RESULTS: The mean aerosol concentration was reduced at the head (p < 0.001) but increased at the feet (p = 0.005) with an aerosol box compared with no intervention. Non-sealed aerosol bags increased exposure at the head and trunk (both, p < 0.001). Sealed aerosol bags reduced aerosol concentration at the head, trunk, and foot of the mannequin (p < 0.001). A sealed aerosol bag alone, with wall suction, or with a HEPA filter evacuator reduced the aerosol concentration at the head by 7.15%, 36.61%, and 84.70%, respectively (99.9% confidence interval [CI]: -4.51-18.81, 27.48-45.73, and 78.99-90.40); trunk by 70.95%, 73.99%, and 91.59%, respectively (99.9% CI: 59.83-82.07, 52.64-95.33, and 87.51-95.66); and feet by 69.16%, 75.57%, and 92.30%, respectively (99.9% CI: 63.18-75.15, 69.76-81.37, and 88.18-96.42), compared with an aerosol box alone. CONCLUSIONS: As aerosols spread, an airtight container with sealed working channels is effective when combined with suction devices.


Assuntos
Aerossóis/química , Poeira/prevenção & controle , Sucção/métodos , Filtros de Ar , Respiradores de Pressão Negativa
10.
Nat Prod Bioprospect ; 9(2): 157-163, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30783922

RESUMO

Bioactivity-guided phytochemical investigation of Podocarpus neriifolius D. Don. (Podocarpaceae) has led to the isolation of one new (2) and three known (1, 3, and 4) B-type podolactones, along with three totarane-type diterpenes (5-7). Their structures were determined by interpretation of High Resolution ElectroSpray Ionization Mass Spectrometry (HRESIMS) and 1D and 2D NMR data, and comparison with the values reported in the literature. The structure of compound 1, previously identified as 3-deoxy-2α-hydroxynagilactone E (8), was revised as its 2ß-epimer, which has been reported recently as a new compound. All of the isolates were evaluated for their antiproliferative activity against a panel of four human cancer cell lines, namely, ovarian (OVCAR3), breast (MDA-MB-231), colon (HT-29), and melanoma (MDA-MB-435), and compounds 1 and 3 were found to be cytotoxic with IC50 values in the low micromolar range for most of the cell lines used. The major compound, inumakilactone A (3), was further tested in vivo using the HT-29, MDA-MB-435, and OVCAR3 cells in a murine hollow fiber model, for the first time.

11.
J Acute Med ; 9(3): 110-117, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32995239

RESUMO

BACKGROUND: The Formosa Fun Coast Dust Explosion is one of the major national disasters in Taiwan. The Taipei City Hospital (TCH), a regional hospital without a burn unit, received 33 patients out of 499 casualties in the initial response period. This retrospective study aimed to review the primary response of TCH and the outcome and mortality of the patients who were initially managed at TCH. METHODS: Basic profi les, total body surface area (TBSA) with burn injury, facial burn injury, vital signs, laboratory data, intubation rate and clinical outcomes, such as urine output and mortality, were analyzed. Moreover, the emergency department (ED) response faculties, who were involved in the initial response, were interviewed about the critical decision-making processes during the patient surge in the ED. RESULTS: The average initial estimated TBSA with burn injury in ED was 34.2%, and the average final TBSA assessed in the intensive care unit was 41.0%. The patients with facial burn injury were 38.7%, and the intubation rate was 22.6%. When comparing the result of TCH to the patient group transferred directly to Chang Gung Memorial Hospital (CGMH), and the group received by CGMH from other hospital, the mortality rate was 0.0, 5.7, 9.1%; and the delayed intubation rate was 3.0, 14.3, 27.3%, respectively. The key elements for effi cient initial response were the multidisciplinary response team cooperated as a production line, using the clipboards for orders recordings, and the plastic surgeons ED-operating room (OR) direct transferring. CONCLUSIONS: Regarding airway complications, and mortality, patients who were initially managed in TCH had comparable results with patients directly sent to the burn centers. This study supports the notion that immediate resuscitation in multiple level of hospitals, even without burn units but with adequate recruited response personnel, provided the best chance for the survival of casualties during such national disasters.

12.
Mar Drugs ; 16(11)2018 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-30423844

RESUMO

Breast tumors reprogram their cellular metabolism, nutrient uptake, and utilization-associated biochemical processes. These processes become further transformed as genetically predisposed metastatic breast tumor cells colonize specific organs. Breast tumor cells often metastasize to the brain, bone, lung and liver. Massagué and colleagues isolated organotropic subclones and established organ-specific gene signatures associated with lung-, bone-, and brain-specific metastatic triple-negative breast cancer (TNBC) MDA-MB-231 cells. Using these genetically characterized metastatic subclones specific to lung (LM4175), bone (BoM1833), and brain (BrM-2a), we evaluated marine natural products for the ability to differentially suppress metastatic breast cancer cells in a target organ-dependent manner. Psammaplin-based histone deacetylase (HDAC) inhibitors were found to differentially inhibit HDAC activity, induce activation of hypoxia-inducible factor-1 (HIF-1), and disrupt organotropic metastatic TNBC subclone growth. Further, psammaplins distinctly suppressed the outgrowth of BoM1833 tumor spheroids in 3D-culture systems. Similar results were observed with the prototypical HDAC inhibitor trichostatin A (TSA). These organotropic tumor cell-based studies suggest the potential application of HDAC inhibitors that may yield new directions for anti-metastatic breast tumor research and drug discovery.


Assuntos
Antineoplásicos/farmacologia , Organismos Aquáticos , Dissulfetos/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Poríferos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Tirosina/análogos & derivados , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Técnicas de Cultura/métodos , Dissulfetos/química , Dissulfetos/isolamento & purificação , Dissulfetos/uso terapêutico , Descoberta de Drogas/métodos , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Feminino , Inibidores de Histona Desacetilases/química , Inibidores de Histona Desacetilases/isolamento & purificação , Inibidores de Histona Desacetilases/uso terapêutico , Histona Desacetilases/metabolismo , Humanos , Esferoides Celulares , Tirosina/química , Tirosina/isolamento & purificação , Tirosina/farmacologia , Tirosina/uso terapêutico
13.
J Med Plant Res ; 11(40): 621-634, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29152156

RESUMO

The Vietnam-Laos International Cooperative Biodiversity Group (ICBG) based at the University of Illinois at Chicago (UIC) catalyzed a country-wide network of medicinal plant preserves (MPP) and medicinal biodiversity preserves (MBP) now established in ten provinces of the Lao People's Democratic Republic (Lao PDR), which are relied upon as protected sources of ethnomedicines for local villagers and traditional healers. In collaboration with the Lao PDR's Institute of Traditional Medicine (ITM), our ongoing P01 Program Project (Ohio State University) examined the anticancer bioprospecting potential for two of the most exhaustively inventoried of these sites: the Bolikhamxay MPP and the Xiengkhouang MBP. Guided by prior voucher specimens sourced from these preserves with an overwhelming emphasis on plants employed in traditional medicine, 201 distinct samples from 96 species were collected along with proper herbarium documentation. Aliquots of these plant samples were extracted in azeotropic ethanol and evaporated to dryness for initial biological evaluation. In six samples from six different species (2.99% of the collected samples, 6.25% of taxa) it was observed that extracts exhibited notable cytotoxicity against HT-29 colon adenocarcinoma cells. The wisdom behind the utilization of HT-29 cells in this preliminary biological screen is discussed. Furthermore, comparison of screening results based on longstanding considerations and ideological underpinnings of ethnobotanical vs. "random" biodiversity-based collection approaches is detailed herein. The results of this interdisciplinary study support the hypothesis that, by privileging the initial sample set in terms of human safety and pharmacological activity, ethnobotanically driven collection for biological screening efforts can produce leads unprecedented by the strict traditional usages of plants.

14.
J Nat Prod ; 80(4): 1073-1080, 2017 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-28252962

RESUMO

Merocyclophanes C and D (1 and 2) were isolated from the cell extract of the cultured cyanobacterium UIC 10110. The structures were determined by one-dimensional nuclear magnetic resonance (NMR) and high-resolution electrospray ionization mass spectrometry and confirmed by 2D NMR techniques. The absolute configurations were determined using electronic circular dichroism spectroscopy. Merocyclophanes C and D represent the first known analogues of the merocyclophane core structure, a recently discovered scaffold of [7,7] paracyclophanes characterized by an α-branched methyl at C-1/C-14; 1 and 2 showed antiproliferative activity against the MDA-MB-435 cell line with IC50 values of 1.6 and 0.9 µM, respectively. Partial 16S analysis determined UIC 10110 to be a Nostoc sp., and it was found to clade with UIC 10062 Nostoc sp., the only other strain known to produce merocyclophanes. The genome of UIC 10110 was sequenced, and a biosynthetic gene cluster was identified that is proposed to encode type I and type III polyketide synthases that are potentially responsible for production of the merocyclophanes; however, further experiments will be required to verify the true function of the gene cluster. The gene cluster provides a genetic basis for the observed structural differences of the [7,7] paracyclophane core structures.


Assuntos
Compostos Macrocíclicos/isolamento & purificação , Nostoc/química , Animais , Antibacterianos/química , Colorado , Água Doce/microbiologia , Concentração Inibidora 50 , Compostos Macrocíclicos/química , Camundongos , Estrutura Molecular , Nostoc/genética , Ressonância Magnética Nuclear Biomolecular , Espectrometria de Massas por Ionização por Electrospray
15.
J Nat Prod ; 80(3): 659-669, 2017 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-28234008

RESUMO

(+)-Strebloside, a cardiac glycoside isolated from the stem bark of Streblus asper collected in Vietnam, has shown some potential for further investigation as an antineoplastic agent. A mechanistic study using an in vitro assay and molecular docking analysis indicated that (+)-strebloside binds and inhibits Na+/K+-ATPase in a similar manner to digitoxin. Inhibition of growth of different high-grade serous ovarian cancer cells including OVCAR3, OVSAHO, Kuramochi, OVCAR4, OVCAR5, and OVCAR8 resulted from treatment with (+)-strebloside. Furthermore, this compound blocked cell cycle progression at the G2 phase and induced PARP cleavage, indicating apoptosis activation in OVCAR3 cells. (+)-Strebloside potently inhibited mutant p53 expression through the induction of ERK pathways and inhibited NF-κB activity in human ovarian cancer cells. However, in spite of its antitumor potential, the overall biological activity of (+)-strebloside must be regarded as being typical of better-known cardiac glycosides such as digoxin and ouabain. Further chemical alteration of cardiac glycosides might help to reduce negative side effects while increasing cancer cell cytotoxicity.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Glicosídeos Cardíacos/isolamento & purificação , Glicosídeos Cardíacos/farmacologia , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , Antineoplásicos Fitogênicos/química , Apoptose/efeitos dos fármacos , Carcinoma Epitelial do Ovário , Glicosídeos Cardíacos/química , Digoxina/farmacologia , Feminino , Células HT29 , Humanos , Estrutura Molecular , NF-kappa B/metabolismo , Neoplasias Epiteliais e Glandulares , Ouabaína/farmacologia , Neoplasias Ovarianas , Transdução de Sinais/efeitos dos fármacos , Estereoisomerismo
16.
J Nat Prod ; 80(3): 648-658, 2017 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-27983842

RESUMO

Three new (1-3) and two known (4 and 5) cytotoxic cardiac glycosides were isolated and characterized from a medicinal plant, Streblus asper Lour. (Moraceae), collected in Vietnam, with six new analogues and one known derivative (5a-g) synthesized from (+)-strebloside (5). A preliminary structure-activity relationship study indicated that the C-10 formyl and C-5 and C-14 hydroxy groups and C-3 sugar unit play important roles in the mediation of the cytotoxicity of (+)-strebloside (5) against HT-29 human colon cancer cells. When evaluated in NCr nu/nu mice implanted intraperitoneally with hollow fibers facilitated with either MDA-MB-231 human breast or OVCAR3 human ovarian cancer cells, (+)-strebloside (5) showed significant cell growth inhibitory activity in both cases, in the dose range 5-30 mg/kg.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Glicosídeos Cardíacos/isolamento & purificação , Glicosídeos Cardíacos/farmacologia , Moraceae/química , Animais , Antineoplásicos Fitogênicos/química , Glicosídeos Cardíacos/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HT29 , Humanos , Camundongos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Plantas Medicinais , Relação Estrutura-Atividade , Vietnã
18.
Springerplus ; 5(1): 783, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27386269

RESUMO

To further capture the influences of uncertain factors on river bridge safety evaluation, a probabilistic approach is adopted. Because this is a systematic and nonlinear problem, MPP-based reliability analyses are not suitable. A sampling approach such as a Monte Carlo simulation (MCS) or importance sampling is often adopted. To enhance the efficiency of the sampling approach, this study utilizes Bayesian least squares support vector machines to construct a response surface followed by an MCS, providing a more precise safety index. Although there are several factors impacting the flood-resistant reliability of a bridge, previous experiences and studies show that the reliability of the bridge itself plays a key role. Thus, the goal of this study is to analyze the system reliability of a selected bridge that includes five limit states. The random variables considered here include the water surface elevation, water velocity, local scour depth, soil property and wind load. Because the first three variables are deeply affected by river hydraulics, a probabilistic HEC-RAS-based simulation is performed to capture the uncertainties in those random variables. The accuracy and variation of our solutions are confirmed by a direct MCS to ensure the applicability of the proposed approach. The results of a numerical example indicate that the proposed approach can efficiently provide an accurate bridge safety evaluation and maintain satisfactory variation.

19.
J Nat Prod ; 79(7): 1815-21, 2016 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-27340832

RESUMO

Six new pimarane derivatives, including two di-nor-pimaranes (1, 2), two 17-nor-pimaranes (3, 4), and two 17-nor-(9ß-H)-pimaranes (5, 6), were isolated from the tuber of Icacina trichantha. Their structures were elucidated based on spectroscopic and HRMS data. The absolute configurations of 1 and 5 were determined by single-crystal X-ray diffraction, and that of 2 was established by electronic circular dichroism data analysis. Compound 3 possesses a unique C-20 acetal moiety. This is the first report of the isolation of di-nor-(9ß-H)-pimarane derivatives from Icacina plants. Compounds 5 and 6 showed moderate cytotoxicity against MDA-MB-435, MDA-MB-231, and OVCAR3 cell lines, with IC50 values of 2.91-7.60 and 1.48-3.23 µM, respectively.


Assuntos
Abietanos/isolamento & purificação , Magnoliopsida/química , Abietanos/química , Abietanos/farmacologia , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Tubérculos/química
20.
Am J Transl Res ; 8(1): 1-11, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27069535

RESUMO

Increasing evidence has been suggested that microRNA-144 (miR-144) involved in tumor initiation, development and metastasis in various cancers. However, the biological roles and potential mechanisms of miR-144 in laryngeal squamous cell carcinoma (LSCC) remain unclear. In the present study, we discovered that miR-144 expression levels in LSCC tissues were significantly lower than those of adjacent normal tissues. Furthermore, overexpression of miR-144 in LSCC cells inhibited cell proliferation, colony formation, migration, and invasion in vitro. Consistently, stable overexpression of miR-144 suppressed the growth of LSCC cell xenografts in vivo. Bioinformatic algorithms and luciferase reporter assays confirmed that insulin receptor substrate 1 (IRS1) is a direct target of miR-144. Overexpreesion of miR-144 obviously decreased IRS1 expression thereby suppressing phosphatidylinositol 3-kinase (PI3K)/AKT pathway activation. Further functional studies suggested that downregulation of IRS1 had similar effects as that of miR-144 overexpression, and upregulation of IRS1 partially reversed the inhibitory effects of miR-144. These findings suggested that miR-144 functioned as a tumor suppressor in LSCC by targeting IRS1, and that miR-144 might serve as a potential target for LSCC treatment.

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