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1.
J Healthc Eng ; 2023: 6724656, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37284489

RESUMO

Medical device development involves user safety, and it is governed by specific regulations. The failure of medical device developers to consider the influence of users, the environment, and related organizations on product development during the design and development process can result in added risks to the use of medical technologies. Although many studies have examined the medical device development process, there has been no systematic and comprehensive assessment of the key factors affecting medical device development. This research synthesized the value of medical device industry stakeholders' experiences through a literature review and interviews with industry experts. Then, it establishes an FIA-NRM model to identify the key factors affecting medical device development and suggests appropriate pathways for improvement. Results indicate that the development of medical devices should begin with stabilizing organizational characteristics, followed by strengthening technical capability and use environment, and finally, consideration should be given to the user action of medical devices. The results provide medical device developers with optimal development pathways and resource allocation recommendations to support developers in developing medical device development strategies as well as ensuring the safety and effectiveness of the products for end users.

2.
J Ethnopharmacol ; 288: 114995, 2022 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-35032584

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The dried flower bud of Syzygium aromaticum (L.) Merr. & L.M Perry (S. aromaticum) (Myrtaceae), also known as clove, was used in Traditional Chinese Medicine (TCM) to aid gastrointestinal function and treat stomach disorders including vomiting, flatulence and nausea. And it is a food homology medicine which is a promising candidate for H. pylori treatment. H. pylori is a Gram-negative bacterium that infects approximately 50% of the human population worldwide, which is closely related to multiple gastric diseases, including gastric cancer. However, there are still no sufficient studies on the anti-H. pylori activity of S. aromaticum, especially for the mechanism of action. AIM OF STUDY: This study aimed to study the antibacterial activities of S. aromaticum extracts on both antibiotic-sensitive and -resistant H. pylori strains, and to explore the underlying mechanisms of action. MATERIALS AND METHODS: The S. aromaticum extracts were obtained by heat reflux extraction and lyophilized to powder form. The phytochemical analyses were performed by High-performance liquid chromatography (HPLC) and UPLC-electrospray ionization mass spectrometry (ESI-MS). In vitro anti-H. pylori activity was evaluated by broth microdilution method. Mechanism of action studies included morphological observation using electron microscopy, determination of expression of virulence genes by reverse transcription quantitative polymerase chain reaction (RT-qPCR), genes expression profile identification by transcriptomic analysis, and exploration of anti-H. pylori infection mechanisms by network pharmacology analysis and western blotting validation. RESULTS: The S. aromaticum extracts, aqueous extract (AE) and 75% hydroalcoholic extract (HE), exerted significant antibacterial activities against both antibiotic-sensitive and -resistant H. pylori strains with MICs of 160∼320 µg/ml, without developing drug resistance. Among them, AE was bactericide to all the tested strains with MBCs of less than 4MIC, while HE was merely bacteriostatic to most of the tested strains with MBCs of 2MIC∼16MIC. Besides, they showed no antagonistic effects in combination with clarithromycin, metronidazole, levofloxacin, and amoxicillin. Additionally, these extracts altered the morphology and ultrastructure and down-regulated the virulence genes expression of H. pylori. And transcriptomic analysis showed that they regulated genes expression of multiple H. pylori biological processes, including tricarboxylic acid cycle (TAC) and pyruvate metabolic pathways. Furthermore, these extracts combated the abnormal activation of PI3K-Akt and MAPK signaling pathways caused by H. pylori infection. CONCLUSIONS: Overall, the present study firstly analyzed the chemical compositions of S. aromaticum extracts, and then confirmed their activities on both antibiotic-sensitive and -resistant H. pylori strains. In addition, the mechanisms of action of S. aromaticum extracts against H. pylori were found to be destroying the bacterial structure, down-regulating the expression of virulence genes, and interfering TAC and pyruvate metabolic pathways. Finally, S. aromaticum extracts were found to combated the abnormal activation of PI3K-Akt and MAPK signaling pathways to treat H. pylori infection. This study should accelerate further research and application of S. aromaticum against H. pylori infection.


Assuntos
Antibacterianos/farmacologia , Helicobacter pylori/efeitos dos fármacos , Extratos Vegetais/farmacologia , Syzygium/química , Antibacterianos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Farmacorresistência Bacteriana , Regulação Bacteriana da Expressão Gênica , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Helicobacter pylori/patogenicidade , Humanos , Testes de Sensibilidade Microbiana , Farmacologia em Rede , Espectrometria de Massas por Ionização por Electrospray , Virulência/genética
3.
Phytomedicine ; 94: 153844, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34785413

RESUMO

BACKGROUND: Colorectal cancer (CRC) is a widespread cancer with high morbidity and mortality. Chemoresistance and metastasis are the current challenges for CRC treatment. Sanguisorba officinalis Linn. (called DiYu in Chinese, DY) is a traditional Chinese medicine (TCM) whose root is long used as medicinal part. In our previous study, the aqueous extract of DY could inhibit the Wnt/ß-catenin pathway and showed great antitumor effect against CRC. The Wnt/ß-catenin pathway is involved in CRC chemoresistance and metastasis. However, there is little study on the antitumor and antimetastatic effects of DY on resistant CRC cells. The aim of this study is to explore the effect of aqueous extract of DY on the growth and metastasis of 5-fluorouracil (5-FU) sensitive and resistant CRC, and to elucidate the underlying molecular mechanism. METHODOLOGY: In this study, cell viability, cell colony formation and apoptosis analyses were performed to verify the in vitro antitumor effect of DY on 5-FU-sensitive and -resistant CRC cells. Next, transwell assays were used to test the inhibition activity of DY on CRC migration and invasion. Western Blotting assays were carried out to identify the molecular mechanism underlying the efficacy of DY extract. Xenograft CRC nude mice model and tumor metastasis model were used to confirm the in vivo antitumor and antimetastatic effects of DY. RESULTS: DY inhibited cell proliferation and apoptosis via the upregulation of Bax, cleaved-caspase3 and cleaved-PARP proteins and downregulation of Bcl-2 protein. DY also inhibited cell migration and invasion via the downregulation of N-cadherin, vimentin and snail proteins and upregulation of E-cadherin protein, demonstrating that DY suppressed cell metastasis by reversing epithelial-to-mesenchymal transition (EMT) procession. Moreover, the protein expression levels of ß-catenin in whole cell, cytoplasm and nucleus were decreased after DY treatment. Taken together, DY suppressed CRC cell growth and metastasis via inhibition of the Wnt pathway. Additionally, DY also demonstrated effective antitumor and anti-metastasis activities in vivo. CONCLUSIONS: In conclusion, DY suppressed the growth and metastasis of 5-FU-sensitive and -resistant CRC via inhibition of the Wnt pathway, which indicated that DY could be a potential drug to treat CRC patients and improve clinic outcome.


Assuntos
Neoplasias Colorretais , Sanguisorba , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico , Transição Epitelial-Mesenquimal , Fluoruracila/farmacologia , Humanos , Camundongos , Camundongos Nus , Via de Sinalização Wnt , beta Catenina/metabolismo
4.
J Ethnopharmacol ; 283: 114578, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34464702

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Canarium album Raeusch. belongs to the Burseraceae family. Its ripe fruits, known as Qing Guo (QG) in Traditional Chinese Medicine (TCM), are used to treat sore throat, cough, and fish or crab poisoning. QG was reported to have antibacterial activity, and it exerted excellent anti-Helicobacter pylori (H. pylori) activity in our screening of abundant TCM. However, few studies have reported its anti-H. pylori activity and mechanism. AIM OF STUDY: The commonly used eradication therapies for H. pylori infection are antibiotic-based therapies. With the increasing antibiotic resistance of H. pylori, interest in finding alternative therapies has been aroused. This study investigated the phytochemistry profile, in vitro anti-H. pylori activity and possible anti-bacterial mechanism of QG extracts. MATERIALS AND METHODS: QG extracts were obtained by heat reflux extraction, ultrasonic extraction or liquid-liquid extraction with different solvents. The quantitative and qualitative phytochemical analyses were performed by colorimetric determination, high-performance liquid chromatography (HPLC), and UPLC-electrospray ionization mass spectrometry (ESI-MS). In vitro anti- H. pylori activity was assessed by broth micro-dilution method. Mechanism of action studies included morphological observation using electron microscopy, urease inhibition assay and determination of expression of virulence genes by RT-qPCR. RESULTS: All QG extracts especially ethyl acetate extract (QGEAE) were rich in phenolic components, with the minimum inhibitory concentrations (MICs) on H.pylori of 39-625 µg/ml and minimum bactericidal concentrations (MBCs) of 78-1250 µg/ml. Both aqueous extract (QGAE) and QGEAE could induce the morphological and structural changes of H. pylori, inhibit urease activity with IC50 of 1093 µg/ml and 332.90 µg/ml, respectively, and down-regulate the virulence genes, such as vacA and cagA. CONCLUSIONS: QG may exhibit in vitro anti-H. pylori activity by inhibiting growth, destroying the bacterial structure and down-regulating the expression of virulence factors. Moreover, QG is the homology of food and TCM, which can be considered as a safe and convenient agent against H. pylori infection.


Assuntos
Antibacterianos/farmacologia , Burseraceae/química , Helicobacter pylori/efeitos dos fármacos , Extratos Vegetais/farmacologia , Antibacterianos/administração & dosagem , Antibacterianos/isolamento & purificação , Frutas , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/microbiologia , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Extratos Vegetais/administração & dosagem
5.
Chin Med ; 16(1): 33, 2021 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-33865425

RESUMO

BACKGROUND: Helicobacter pylori (H. pylori) infection has become an international public health problem, and antibiotic-based triple or quadruple therapy is currently the mainstay of treatment. However, the effectiveness of these therapies decreases due to resistance to multiple commonly used antibiotics. Sanguisorba officinalis L. (S. officinalis), a traditional Chinese medicine clinically used for hemostasis and treatment of diarrhea, has various pharmacological activities. In this study, in vitro antimicrobial activity was used for the preliminary evaluation of S. officinalis against H. pylori. And a pharmacology analysis approach was also utilized to elucidate its underlying mechanisms against H. pylori infection. METHODS: Micro-broth dilution method, agar dilution method, checkerboard assay, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used for the assessment of anti-bacterial activity. Active ingredients screening, GO analysis, KEGG analysis, construction of PPI network, molecular docking, and RT-qPCR were used to elucidate the underlying pharmacological mechanisms of S. officinalis against H. pylori infection. RESULTS: The minimum inhibitory concentration (MIC) values of S. officinalis against multiple H. pylori strains including clinically isolated multi-drug resistant (MDR) strains were ranging from 160 to 320 µg/ml. These results showed that S. officinalis had additive interaction with four commonly used antibiotics and could exert antibacterial effect by changing the morphology of bacteria without developing drug resistance. Through network pharmacology analysis, 8 active ingredients in S. officinalis were screened out for subsequent studies. Among 222 putative targets of S. officinalis, 49 targets were identified as potential targets for treatment of H. pylori infection. And these 49 targets were significantly enriched in GO processes such as protein kinase B signaling, protein kinase activity, protein kinase binding, and KEGG pathways such as Pathways in cancer, MicroRNAs in cancer, and TNF signaling pathway. Protein-protein interaction analysis yielded 5 core targets (AKT1, VEGFA, EGFR, SRC, CCND1), which were validated by molecular docking and RT-qPCR. CONCLUSIONS: Overall, this study confirmed the in vitro inhibitory activity of S. officinalis against H. pylori and explored the possible pharmacological mechanisms, laying the foundation for further research and clinical application.

6.
Sensors (Basel) ; 20(20)2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33053827

RESUMO

This work presents a fall detection system that is worn on the head, where the acceleration and posture are stable such that everyday movement can be identified without disturbing the wearer. Falling movements are recognized by comparing the acceleration and orientation of a wearer's head using prespecified thresholds. The proposed system consists of a triaxial accelerometer, gyroscope, and magnetometer; as such, a Madgwick's filter is adopted to improve the accuracy of the estimation of orientation. Moreover, with its integrated Wi-Fi module, the proposed system can notify an emergency contact in a timely manner to provide help for the falling person. Based on experimental results concerning falling movements and activities of daily living, the proposed system achieved a sensitivity of 96.67% in fall detection, with a specificity of 98.27%, and, therefore, is suitable for detecting falling movements in daily life.


Assuntos
Acidentes por Quedas , Atividades Cotidianas , Algoritmos , Dispositivos Eletrônicos Vestíveis , Aceleração , Humanos , Movimento
7.
Healthcare (Basel) ; 8(4)2020 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-33113863

RESUMO

COVID-19 has been impacting the Med-Tech industry dramatically since the beginning of 2020. Along with the pandemic continuously growing, the demand for major global medical products such as masks and protective clothing has surged. The Med-Tech industry is facing the huge challenge of a lack of production capacity, including raw material, production equipment, production line, professional human resources, and more. It would require not only the operators in the Med-Tech industry to enlarge their productivity, but also new investors from outside. This study focused on the entry strategy analysis of the Med-Tech industry, developing five driving factors, and conducting an opinion survey from three different aspects, including vendors, channels, and end-users, under COVID-19 impact. A total of 99 valid questionnaires were collected. After that, the Importance Accessibility Analysis-Network Relation Map (IAA-NRM) approach was used to verify the importance and implementation priority of the entry strategies. Then, the Decision Making Trial and Evaluation Laboratory (DEMATEL) technique is used to construct the NRM method. The research results showed that there is a common strategic path, from the regulatory system to operation resources and then marketing promotion. In addition, in these three viewpoints, vendors and end-users have similar priorities in terms of industry attributes and barriers to entry.

8.
Sensors (Basel) ; 20(12)2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-32580328

RESUMO

In the context of assisted human, identifying and enhancing non-stationary speech targets speech in various noise environments, such as a cocktail party, is an important issue for real-time speech separation. Previous studies mostly used microphone signal processing to perform target speech separation and analysis, such as feature recognition through a large amount of training data and supervised machine learning. The method was suitable for stationary noise suppression, but relatively limited for non-stationary noise and difficult to meet the real-time processing requirement. In this study, we propose a real-time speech separation method based on an approach that combines an optical camera and a microphone array. The method was divided into two stages. Stage 1 used computer vision technology with the camera to detect and identify interest targets and evaluate source angles and distance. Stage 2 used beamforming technology with microphone array to enhance and separate the target speech sound. The asynchronous update function was utilized to integrate the beamforming control and speech processing to reduce the effect of the processing delay. The experimental results show that the noise reduction in various stationary and non-stationary noise environments were 6.1 dB and 5.2 dB respectively. The response time of speech processing was less than 10ms, which meets the requirements of a real-time system. The proposed method has high potential to be applied in auxiliary listening systems or machine language processing like intelligent personal assistant.

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