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1.
Sci Rep ; 14(1): 6640, 2024 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-38503839

RESUMO

Automated coronary angiography assessment requires precise vessel segmentation, a task complicated by uneven contrast filling and background noise. Our research introduces an ensemble U-Net model, SE-RegUNet, designed to accurately segment coronary vessels using 100 labeled angiographies from angiographic images. SE-RegUNet incorporates RegNet encoders and squeeze-and-excitation blocks to enhance feature extraction. A dual-phase image preprocessing strategy further improves the model's performance, employing unsharp masking and contrast-limited adaptive histogram equalization. Following fivefold cross-validation and Ranger21 optimization, the SE-RegUNet 4GF model emerged as the most effective, evidenced by performance metrics such as a Dice score of 0.72 and an accuracy of 0.97. Its potential for real-world application is highlighted by its ability to process images at 41.6 frames per second. External validation on the DCA1 dataset demonstrated the model's consistent robustness, achieving a Dice score of 0.76 and an accuracy of 0.97. The SE-RegUNet 4GF model's precision in segmenting blood vessels in coronary angiographies showcases its remarkable efficiency and accuracy. However, further development and clinical testing are necessary before it can be routinely implemented in medical practice.


Assuntos
Lesões Acidentais , Vasos Coronários , Humanos , Vasos Coronários/diagnóstico por imagem , Angiografia Coronária , Benchmarking , Exame Físico , Processamento de Imagem Assistida por Computador
2.
Neurology ; 102(5): e209140, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38330286

RESUMO

BACKGROUND AND OBJECTIVES: Multimorbidity is common in patients who experience stroke. Less is known about the effect of specific multimorbidity patterns on long-term disability in patients with stroke. Furthermore, given the increased poststroke disability frequently seen in female vs male patients, it is unknown whether multimorbidity has a similar association with disability in both sexes. We assessed whether specific multimorbidity clusters were associated with greater long-term poststroke disability burden overall and by sex. METHODS: In the Taiwan Stroke Registry, an ongoing nationwide prospective registry, patients with first-ever ischemic stroke were enrolled; this analysis is restricted to those individuals surviving to at least 6 months poststroke. Using a hierarchical clustering approach, clusters of prestroke multimorbidity were generated based on 16 risk factors; the algorithm identified 5 distinct clusters. The association between clusters and 12-month poststroke disability, defined using the modified Rankin Scale (mRS), was determined using logistic regression models, with additional models stratified by sex. The longitudinal association between multimorbidity and functional status change was assessed using mixed-effects models. RESULTS: Nine-thousand eight hundred eighteen patients with first-ever ischemic stroke were included. The cluster with no risk factors was the reference, "healthier" risk group (N = 1,373). Patients with a cluster profile of diabetes, peripheral artery disease (PAD), and chronic kidney disease (CKD) (N = 1882) had significantly greater disability (mRS ≥ 3) at 1 month (OR [95% CI] = 1.36 [1.13-1.63]), 3 months (OR [95% CI] = 1.27 [1.04-1.55]), and 6 months (OR [95% CI] = 1.30 [1.06-1.59]) but not at 12 months (OR [95% CI] = 1.16 [0.95-1.42]) than patients with a healthier risk factor profile. In the sex-stratified analysis, the associations with this risk cluster remained consistent in male patients (OR [95% CI] = 1.42 [1.06-1.89]) at 12 months, who also had a higher comorbidity burden, but not in female patients (OR [95% CI] = 0.95 [0.71-1.26]), who had higher proportions of severe strokes and severe disability (p-interaction = 0.04). DISCUSSION: Taiwanese patients with multimorbidity, specifically the concurrent presence of diabetes, PAD, and CKD, had higher odds of a worse functional outcome in the first 6 months poststroke. Clusters of multimorbidity may be less informative for long-term disability in female patients. Further studies should evaluate other mechanisms for worse disability in female patients poststroke.


Assuntos
Diabetes Mellitus , AVC Isquêmico , Insuficiência Renal Crônica , Acidente Vascular Cerebral , Humanos , Masculino , Feminino , Multimorbidade , Caracteres Sexuais , Taiwan/epidemiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/epidemiologia , Diabetes Mellitus/epidemiologia , Sistema de Registros
3.
Eur J Med Chem ; 262: 115874, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37918036

RESUMO

Neutrophils are the most abundant immune cells. However, neutrophil dysregulation leads to acute and chronic inflammation and is involved in various diseases. The aim of this study was to develop anti-inflammatory agents in human neutrophils. A drug screening was conducted on in-house compounds with the potential to inhibit the respiratory burst, which involves the generation of superoxide anions in human neutrophils. Bioisosteric replacement was then applied to design more active derivatives. The most potent inhibitors of superoxide anion generation activity were compounds 58 and 59, which had IC50 values of 13.30 and 9.06 nM, respectively. The inhibitory effects of 58 and 59 were reversed by H89, a PKA inhibitor. PDE selective screening indicated that the best inhibitory effects were PDE4B1 and PDE4D2, and the inhibitory activities were 83% and 85%, respectively, at a 10 µM concentration of 59. The final molecular simulation experiment highlighted the slightly different binding poses of 58 and 59 in the PDE4 active site. An in vivo pharmacokinetic study revealed that the half-life of 59 was approximately 79 min when using intravenous bolus administration. This work introduced a new class structure of PDE4 inhibitors resulting in potent neutrophil inactivation activity, with the aim of contributing to new anti-inflammatory drug discovery.


Assuntos
Inibidores da Fosfodiesterase 4 , Superóxidos , Humanos , Superóxidos/metabolismo , Superóxidos/farmacologia , Anti-Inflamatórios/uso terapêutico , Inibidores da Fosfodiesterase 4/farmacologia , Inibidores da Fosfodiesterase 4/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Pirazóis/farmacologia , Pirazóis/metabolismo , Neutrófilos
4.
Biotechnol Prog ; 39(4): e3340, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36970759

RESUMO

Perfusion culture is often performed with micro-sparger to fulfill the high oxygen demand from the densified cells. Protective additive Pluronic F-68 (PF-68) is widely used to mitigate the adverse effect in cell viability from micro-sparging. In this study, different PF-68 retention ratio in alternating tangential filtration (ATF) columns was found to be crucial for cell performance of different perfusion culture modes. The PF-68 in the perfusion medium was found retained inside the bioreactor when exchanged through ATF hollow fibers with a small pore size (50 kD). The accumulated PF-68 could provide sufficient protection for cells under micro-sparging. On the other hand, with large-pore-size (0.2 µm) hollow fibers, PF-68 could pass through the ATF filtration membranes with little retention, and consequently led to compromised cell growth. To overcome the defect, a PF-68 feeding strategy was designed and successfully verified on promoting cell growth with different Chinese hamster ovary (CHO) cell lines. With PF-68 feeding, enhancements were observed in both viable cell densities (20%-30%) and productivity (~30%). A threshold PF-68 concentration of 5 g/L for high-density cell culture (up to 100 × 106 cells/mL) was also proposed and verified. The additional PF-68 feeding was not observed to affect product qualities. By designing the PF-68 concentration of perfusion medium to or higher than the threshold level, a similar cell growth enhancement was also achieved. This study systematically investigated the protecting role of PF-68 in intensified CHO cell cultures, shedding a light on the optimization of perfusion cultures through the control of protective additives.


Assuntos
Reatores Biológicos , Poloxâmero , Cricetinae , Animais , Cricetulus , Células CHO , Poloxâmero/farmacologia , Técnicas de Cultura de Células , Perfusão
5.
Diagnostics (Basel) ; 13(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36672980

RESUMO

Using a deep learning algorithm in the development of a computer-aided system for colon polyp detection is effective in reducing the miss rate. This study aimed to develop a system for colon polyp detection and classification. We used a data augmentation technique and conditional GAN to generate polyp images for YOLO training to improve the polyp detection ability. After testing the model five times, a model with 300 GANs (GAN 300) achieved the highest average precision (AP) of 54.60% for SSA and 75.41% for TA. These results were better than those of the data augmentation method, which showed AP of 53.56% for SSA and 72.55% for TA. The AP, mAP, and IoU for the 300 GAN model for the HP were 80.97%, 70.07%, and 57.24%, and the data increased in comparison with the data augmentation technique by 76.98%, 67.70%, and 55.26%, respectively. We also used Gaussian blurring to simulate the blurred images during colonoscopy and then applied DeblurGAN-v2 to deblur the images. Further, we trained the dataset using YOLO to classify polyps. After using DeblurGAN-v2, the mAP increased from 25.64% to 30.74%. This method effectively improved the accuracy of polyp detection and classification.

6.
ANZ J Surg ; 93(6): 1613-1619, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36597982

RESUMO

BACKGROUNDS: Magnetic resonance imaging is the primary method for local staging in rectal cancer patients. Administration of intravenous (IV) hyoscine butylbromide is thought to improve accuracy, but there are contraindications and potential adverse effects. The aim was to assess the efficacy of IV hyoscine butylbromide on the accuracy of MRI rectal cancer staging of T2 and T3 rectal cancers. METHODS: A retrospective cohort study was carried out on patients prospectively recorded on the Cabrini Monash colorectal neoplasia database. A total of 74 patients (53 males, 21 females) MRI pelvis and rectums with antispasmodics were performed at multiple centres in the pre-operative setting between 2010 and 2016. Each patient underwent total mesorectal excision of rectal cancer. The excision specimens were assessed and given a pathological TNM stage, which was considered the reference standard. RESULTS: There was no statistically significant impact on the overall accuracy of MRI rectal cancer staging between patient groups who received IV hyoscine butylbromide and groups who did not receive IV hyoscine butylbromide. The accuracy of T2 and T3 staged rectal cancers was more likely to be correct (compared with T1 cancers) with the administration of IV hyoscine butylbromide. Still, there was no improvement in the accuracy of N-staging. CONCLUSION: Given the potential side effects and adverse outcomes of IV anti-spasmodic agents, department protocols may need to be re-assessed regarding the prescription of these medications for MRI rectal cancer staging.


Assuntos
Neoplasias Retais , Escopolamina , Masculino , Feminino , Humanos , Estudos Retrospectivos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/cirurgia , Neoplasias Retais/patologia , Brometo de Butilescopolamônio/uso terapêutico , Imageamento por Ressonância Magnética/métodos , Estadiamento de Neoplasias
7.
Int J Colorectal Dis ; 38(1): 11, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36633697

RESUMO

PURPOSE: In 2019, in Australia, there were 500,000 people aged 85 and over. Traditionally, clinicians have adopted the view that surgery is not desirable in this cohort due to increasing perioperative risk, perceived minimal clinical benefit, and shortened life expectancy. This cohort study is aimed at investigating postoperative outcomes from elective and non-elective colorectal cancer surgery in patients aged 80 and over. METHODS: A retrospective analysis was conducted on patients from 2010 to 2020 on a prospectively maintained colorectal database. Patients aged over 80 who underwent surgical resection for colorectal cancer were reviewed. Oncological characteristics, short-term outcomes, overall survival, and relapse-free survival rates were analysed. RESULTS: A total of 832 patients were identified from the database. Females comprised 55% of patients aged 80 and above. The median age was 84 for octogenarians and 92 for nonagenarians. Most patients were ASA 2 (212) or ASA 3 (501). ASA 3 and 4 and stage III pathology were associated with higher postoperative complications. Fifty percent of over 80 s and 37% of over 90 s were surgically discharged to their own home. Overall survival at 30, 180, and 360 days and 5 years was 98.1%, 93.1%, 87.2%, and 57.2% for the over 80 s and 98.1%, 88.9%, 74.9%, and 24.4% for the over 90 s. CONCLUSION: Our results demonstrate that surgical treatment of older patients is safe with acceptable short-, medium-, and long-term survival. Nonetheless, efforts are needed to reduce the rates of complications in older patients, including utilisation of multi-disciplinary teams to assess the optimal treatment strategy and postoperative care.


Assuntos
Neoplasias Colorretais , Procedimentos Cirúrgicos do Sistema Digestório , Idoso de 80 Anos ou mais , Feminino , Humanos , Idoso , Masculino , Estudos Retrospectivos , Estudos de Coortes , Neoplasias Colorretais/patologia , Recidiva Local de Neoplasia , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento
8.
Anticancer Res ; 42(9): 4403-4410, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36039427

RESUMO

BACKGROUND/AIM: Osteosarcoma is an aggressive primary malignant bone tumor that occurs in childhood. Although the diagnostic and treatment options have been improved, osteosarcoma confers poor prognosis. Magnolol, an active component of Magnoliae officinalis cortex, has been widely applied in herb medicine and has been shown to have multiple pharmacological activities. However, whether magnolol possesses anti-osteosarcoma capacity remains unknown. MATERIALS AND METHODS: We examined magnolol is cytotoxicity, and whether it regulates apoptosis and oncogene expression using MTT, flow cytometry and Western blotting assays in osteosarcoma cells. RESULTS: Magnolol exerted toxicity towards U-2 OS cells by inducing intrinsic/extrinsic apoptosis pathways. Additionally, treatment of U-2 OS cells with magnolol inhibited MAPK1 mitogen-activated protein kinase 1 (ERK)/Nuclear factor kappa B (NF-B) signaling involved in tumor progression and reduced the expression of anti-apoptotic and metastasis-associated genes. CONCLUSION: Magnolol may induce apoptosis and inactivate ERK/NF-B signal transduction in osteosarcoma cells.


Assuntos
Neoplasias Ósseas , Lignanas , Osteossarcoma , Apoptose , Compostos de Bifenilo/farmacologia , Neoplasias Ósseas/tratamento farmacológico , Linhagem Celular Tumoral , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Lignanas/farmacologia , NF-kappa B/metabolismo , Osteossarcoma/tratamento farmacológico , Osteossarcoma/genética , Transdução de Sinais
9.
ACS Nano ; 16(8): 12979-12990, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35815946

RESUMO

Recently, conductive-bridging memristors based on metal halides, such as halide perovskites, have been demonstrated as promising components for brain-inspired hardware-based neuromorphic computing. However, realizing devices that simultaneously fulfill all of the key merits (low operating voltage, high dynamic range, multilevel nonvolatile storage capability, and good endurance) remains a great challenge. Herein, we describe lead-free cesium halide memristors incorporating a MoOX interfacial layer as a type of conductive-bridging memristor. With this design, we obtained highly uniform and reproducible memristors that exhibited all-around resistive switching characteristics: ultralow operating voltages (<0.18 V), low variations (<30 mV), long retention times (>106 s), high endurance (>105, full on/off cycles), record-high on/off ratios (>1010, smaller devices having areas <5 × 10-4 mm2), fast switching (<200 ns), and multilevel programming abilities (>64 states). With these memristors, we successfully implemented stateful logic functions in a reconfigurable architecture and accomplished a high classification accuracy (ca. 90%) in the simulated hand-written-digits classification task, suggesting their versatility in future in-memory computing applications. In addition, we exploited the room-temperature fabrication of the devices to construct a fully functional three-dimensional stack of memristors, which demonstrates their potential of high-density integration desired for data-intensive neuromorphic computing. High-performance, environmentally friendly cesium halide memristors provide opportunities toward next-generation electronics beyond von Neumann architectures.

10.
World J Clin Cases ; 10(12): 3677-3685, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35647155

RESUMO

BACKGROUND: In a previous study, basilar artery occlusion (BAO) was shown to lead to death or disability in 80% of the patients. The treatment for BAO patients in the acute stage includes thrombolysis and intra-arterial thrombectomy, but not all patients benefit from these treatments. Thus, understanding the predictors of outcome before initiating these treatments is of special interest. AIM: To determine the predictors related to the 90-d clinical outcome in patients with BAO in an Asian population. METHODS: We performed a retrospective case review of patients admitted to a tertiary stroke center between 2015 and 2019. We used the international classification of diseases-10 criteria to identify cases of posterior circulation stroke. A neurologist reviewed every case, and patients fulfilling the criteria defined in the Basilar Artery International Cooperation Study were included. We then analyzed the patients' characteristics and factors related to the 90-d outcome. RESULTS: We identified a total of 99 patients as real BAO cases. Of these patients, 33 (33.3%) had a favorable outcome at 90 d (modified Rankin Scale: 0-3). Moreover, 72 patients received intra-arterial thrombectomy, while 13 patients received intravenous tissue-type plasminogen activator treatment. We observed a favorable outcome in 33.3% of the cases and an unfavorable outcome in 66.7% of the cases. We found that the initial National Institutes of Health Stroke Scale (NIHSS) score and several BAO symptoms, including impaired consciousness, tetraparesis, and pupillary abnormalities, were significantly associated with an unfavorable outcome (P < 0.05), while cerebellar symptoms were associated with a favorable outcome (P < 0.05). In the receiver operating characteristic (ROC) analysis, the areas under the ROC curve of initial NIHSS score, impaired consciousness, tetraparesis, cerebellar symptoms, and pupillary abnormalities were 0.836, 0.644, 0.727, 0.614, and 0.614, respectively. Initial NIHSS score showed a higher AUROC (0.836) compared to BAO symptoms. CONCLUSION: The most important predictor of an unfavorable outcome was the initial NIHSS score. BAO symptoms, including tetraparesis, impaired consciousness, and pupillary abnormality were also related to an unfavorable outcome.

11.
ANZ J Surg ; 92(6): 1472-1479, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35403808

RESUMO

BACKGROUND: This study aimed to investigate whether an extracorporeal side-to-side (SS) or end-to-side (ES) stapled anastomosis impacts short-term and long-term outcomes after an oncological laparoscopic right hemicolectomy. METHODS: A retrospective cohort study of prospectively collected data from two Victorian tertiary referral hospitals was performed. Patients who underwent oncological resection for colorectal cancer between February 2010 and September 2020 were selected from the colorectal neoplasia database. Patients were divided into two groups depending on the type of stapled anastomosis: Group 1 (functional end-to-end/side-to-side (SS)); and Group 2 (end-to-side (ES)). Primary outcomes were anastomotic leak, postoperative ileus, mortality and morbidity, length of stay post-surgery, readmission to hospital, and 30-day mortality. RESULTS: This large case series of 1040 patients (SS = 625, ES = 415) demonstrated that the type of stapling technique impacted operative duration and postoperative ileus rates. Patients in the SS group had a faster operation of 108 min rather than 130 min in the ES group (p < 0.001). The SS group were more likely to experience a post-operative ileus (p < 0.001) with no impact on length of stay (SS, 7 days versus ES, 7 days; p = 0.14). There were no differences between the two groups with respect to lymph node yield, lymph node ratio, anastomotic leaks, return to theatre, 30-day mortality and 5-year overall survival. DISCUSSION: The type of extracorporeal stapled anastomosis following an oncological laparoscopic right hemicolectomy has minimal impact on morbidity and survival outcomes; however, a side-to-side stapled anastomosis is more likely to be a faster operation with a higher postoperative ileus rate.


Assuntos
Neoplasias do Colo , Íleus , Laparoscopia , Anastomose Cirúrgica/efeitos adversos , Anastomose Cirúrgica/métodos , Fístula Anastomótica/epidemiologia , Fístula Anastomótica/etiologia , Fístula Anastomótica/cirurgia , Colectomia/efeitos adversos , Colectomia/métodos , Colo/cirurgia , Neoplasias do Colo/cirurgia , Humanos , Íleus/epidemiologia , Íleus/etiologia , Íleus/cirurgia , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos
12.
Sensors (Basel) ; 22(3)2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35161525

RESUMO

Music can generate a positive effect in runners' performance and motivation. However, the practical implementation of music intervention during exercise is mostly absent from the literature. Therefore, this paper designs a playback sequence system for joggers by considering music emotion and physiological signals. This playback sequence is implemented by a music selection module that combines artificial intelligence techniques with physiological data and emotional music. In order to make the system operate for a long time, this paper improves the model and selection music module to achieve lower energy consumption. The proposed model obtains fewer FLOPs and parameters by using logarithm scaled Mel-spectrogram as input features. The accuracy, computational complexity, trainable parameters, and inference time are evaluated on the Bi-modal, 4Q emotion, and Soundtrack datasets. The experimental results show that the proposed model is better than that of Sarkar et al. and achieves competitive performance on Bi-modal (84.91%), 4Q emotion (92.04%), and Soundtrack (87.24%) datasets. More specifically, the proposed model reduces the computational complexity and inference time while maintaining the classification accuracy, compared to other models. Moreover, the size of the proposed model for network training is small, which can be applied to mobiles and other devices with limited computing resources. This study designed the overall playback sequence system by considering the relationship between music emotion and physiological situation during exercise. The playback sequence system can be adopted directly during exercise to improve users' exercise efficiency.


Assuntos
Música , Algoritmos , Inteligência Artificial , Emoções , Redes Neurais de Computação
13.
Aust Crit Care ; 35(1): 34-39, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34654611

RESUMO

BACKGROUND: Coronavirus disease-2019 (COVID-19) has effected major changes to healthcare delivery within acute care settings. Rapid response calls (RRCs) in healthcare organisations have been effective at identifying and urgently managing acute clinical deterioration. Code-95 RRC were introduced to prewarn healthcare workers (HCWs) attending to patients suspected or confirmed with COVID-19 infection. AIMS: The primary aim of the study was to identify the personal impact of the COVID-19 pandemic on HCWs involved in attending Code-95 RRC. We sought to evaluate their perception of risks and effects on wellbeing and identify potential opportunities for improvement at organisational levels. METHODS: We undertook a detailed survey on HCWs attending Code-95 RRCs, including questions that sought to understand the impact of the pandemic as well as their perception of infection risk and emotional wellbeing. This was a substudy of the prospective cross-sectional single-centre survey of HCWs that was conducted over a 3-week period at Frankston Hospital, Victoria, Australia. We adopted a quantitative content analysis approach for free-text responses in this secondary analysis. RESULTS: Four hundred two free-text comments were received from 297 respondents and were analysed. More than two-thirds (68%, 223/297) were female. Of all comments, 39% (155/402) were related to organisational issues including communication, confusion due to constantly changing infection control policies, and insufficient training. Thirty-three percent of comments (133/402) raised issues regarding the adequacy of personal protective equipment. Anxiety was reported in 25% of comments (101/402) with concerns predominantly relating to emotional stress and fatigue, risks of virus exposure and transmitting the infection to others, and COVID-19 precautions impairing care delivery. CONCLUSION(S): Our study raises important issues that have relevance for all healthcare organisations in the management of patients with COVID-19. These include the importance of improving communication, especially when infection control policies are revised, optimising training, maintaining adequate personal protective equipment, and HCW support. Early recognition and management of these issues are crucial to maintain optimal healthcare delivery.


Assuntos
COVID-19 , Pandemias , Estudos Transversais , Feminino , Pessoal de Saúde , Humanos , Percepção , Estudos Prospectivos , SARS-CoV-2 , Vitória
14.
Appl Microbiol Biotechnol ; 105(24): 9125-9136, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34811605

RESUMO

Product retention in hollow fibers is a common issue in ATF-based cell culture system. In this study, the effects of four major process factors on product (therapeutic antibody/recombinant protein) retention were investigated using Chinese hamster ovary cell. Hollow fibers made of polysulfone presented a product retention rate from 15% ± 8 to 43% ± 18% higher than those made of polyether sulfone varying with specific processes. Higher harvest flowrate and ATF exchange rate increased product retention by 13% ± 10% and up to 31% ± 13%, respectively. Hollow fibers with larger pore sizes (0.65 µm) appeared to have increased product retention by 38% ± 7% compared with smaller ones (0.2 µm) in this study. Further investigation revealed that the effects of pore size on retention could be correlated to the particle size distribution in the cell culture broth. A hollow fiber with a larger pore size (>0.5 µm) may reduce protein retention when small particles (approximately 0.01-0.2 µm in diameter) are dominant in the culture. However, if majority of the particles are larger than 0.2 µm in diameter, hollow fiber with smaller pore sizes (0.2 µm) could be a solution to reducing product retention. Alternatively, process optimization may modulate particle size distribution towards reduced production retention with selected ATF hollow fibers. This study for the first time highlights the importance of matching proper pore sizes of hollow fibers with the cell culture particles distribution and offers methods to reducing product retention and ATF column clogging in perfusion cell cultures. KEY POINTS: The material of ATF column could impact product retention during perfusion culture. Higher harvest flowrate and ATF exchange rate increased product retention. Matching culture particle size and ATF pore size is critical for retention modulation.


Assuntos
Reatores Biológicos , Técnicas de Cultura de Células , Animais , Células CHO , Cricetinae , Cricetulus , Perfusão
15.
J Formos Med Assoc ; 120 Suppl 1: S26-S37, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34083090

RESUMO

BACKGROUND: As Coronavirus disease 2019 (COVID-19) pandemic led to the unprecedent large-scale repeated surges of epidemics worldwide since the end of 2019, data-driven analysis to look into the duration and case load of each episode of outbreak worldwide has been motivated. METHODS: Using open data repository with daily infected, recovered and death cases in the period between March 2020 and April 2021, a descriptive analysis was performed. The susceptible-exposed-infected-recovery model was used to estimate the effective productive number (Rt). The duration taken from Rt > 1 to Rt < 1 and case load were first modelled by using the compound Poisson method. Machine learning analysis using the K-means clustering method was further adopted to classify patterns of community-acquired outbreaks worldwide. RESULTS: The global estimated Rt declined after the first surge of COVID-19 pandemic but there were still two major surges of epidemics occurring in September 2020 and March 2021, respectively, and numerous episodes due to various extents of Nonpharmaceutical Interventions (NPIs). Unsupervised machine learning identified five patterns as "controlled epidemic", "mutant propagated epidemic", "propagated epidemic", "persistent epidemic" and "long persistent epidemic" with the corresponding duration and the logarithm of case load from the lowest (18.6 ± 11.7; 3.4 ± 1.8)) to the highest (258.2 ± 31.9; 11.9 ± 2.4). Countries like Taiwan outside five clusters were classified as no community-acquired outbreak. CONCLUSION: Data-driven models for the new classification of community-acquired outbreaks are useful for global surveillance of uninterrupted COVID-19 pandemic and provide a timely decision support for the distribution of vaccine and the optimal NPIs from global to local community.


Assuntos
COVID-19 , Pandemias , COVID-19/epidemiologia , Infecções Comunitárias Adquiridas/classificação , Surtos de Doenças , Humanos , Aprendizado de Máquina , Modelos Estatísticos , SARS-CoV-2 , Taiwan
16.
Front Neurol ; 12: 606673, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34135840

RESUMO

Background: In most countries, large cerebral artery occlusion is identified as the leading cause of disability. In 2015, five large-scale clinical trials confirmed the benefit of intra-arterial thrombectomy. However, thrombectomy is a highly technical and facility-dependent procedure. Primary stroke centers need to transfer patients to comprehensive stroke centers to perform thrombectomy. The time-lapse during interhospital transfer would decrease the chance of the patient's proper recovery. Communication barriers also contribute to this delay. Aims: We used a smartphone application to overcome communication barriers between hospitals. We aimed to shorten the door-to-puncture time of interhospital transfer patients. Methods: We began using a smartphone application, "LINE," to facilitate interhospital communication on May 01, 2018. We carried out retrospective data analyses for all the transfer patients (n = 351), with the primary outcome being the door-to-puncture time in our comprehensive stroke center (China Medical University Hospital). We compared the three periods: May 01 to Dec 31, 2017 (before the use of the smartphone application); May 01 to Dec 31, 2018 (the 1st year of using the smartphone application); and May 01 to Dec 31, 2019 (the 2nd year of using the smartphone application). We also compared the transfer data with non-transfer thrombectomies in the same period. Results: We compared 2017, 2018, and 2019 data. The total number of transfer patients increased over the years: 63, 113, 175, respectively. The mean door-to-puncture time decreased significantly, going from 109, through 102, to 92 min. Meanwhile, the mean door-to-puncture time in non-transfer patients were 140.3, 122.1, and 129.3 min. The main reason of time saving was the change of the way of communication, from point-to-point interhospital communication to hub-to-spoke interhospital communication. Conclusions: We used this smartphone application to enhance interhospital communication, changed from the point-to-point to hub-to-spoke method. It made us overcome the communication barrier and build up interhospital connection, thus shortening the door-to-puncture time. Our experience demonstrated the importance of close communication and teamwork in hyperacute stroke care, especially in interhospital transfer for thrombectomy.

17.
J Formos Med Assoc ; 120 Suppl 1: S19-S25, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34112588

RESUMO

BACKGROUND: As COVID-19 has become a pandemic emerging infectious disease it is important to examine whether there was a spatiotemporal clustering phenomenon in the globe during the rapid spread after the first outbreak reported from southern China. MATERIALS AND METHODS: The open data on the number of COVID-19 cases reported at daily basis form the globe were used to assess the evolution of outbreaks with international air link on the same latitude and also including Taiwan. The dynamic Susceptible-Infected-Recovered model was used to evaluate continental transmission from December 2019 to March 2020 before the declaration of COVID-19 pandemic with basic reproductive number and effective reproductive number before and after containment measurements. RESULTS: For the initial COVID-19 outbreak in China, the estimated reproductive number was reduced from 2.84 during the overwhelming outbreaks in early January to 0.43 after the strict lockdown policy. It is very surprising to find there were three countries (including South Korea, Iran, and Italy) and the Washington state of the USA on the 38° North Latitude involved with large-scale community-acquired outbreaks since the first imported COVID-19 cases from China. The propagation of continental transmission was augmented from hotspot to hotspot with higher reproductive number immediately before the declaration of pandemic. By contrast, there was not any large community-acquired outbreak in Taiwan. CONCLUSION: The propagated spatiotemporal transmission from China to other hotspots may explain the emerging pandemic that can only be exempted by timely border control and preparedness of containment measurements according to Taiwan experience.


Assuntos
COVID-19 , Pandemias , COVID-19/transmissão , China/epidemiologia , Controle de Doenças Transmissíveis , Infecções Comunitárias Adquiridas/transmissão , Humanos , Irã (Geográfico)/epidemiologia , Itália/epidemiologia , República da Coreia/epidemiologia , SARS-CoV-2 , Taiwan/epidemiologia , Washington/epidemiologia
18.
J Formos Med Assoc ; 120 Suppl 1: S95-S105, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34108119

RESUMO

BACKGROUND: Vaccine is supposed to be the most effective means to prevent COVID-19 as it may not only save lives but also reduce productivity loss due to resuming pre-pandemic activities. Providing the results of economic evaluation for mass vaccination is of paramount importance for all stakeholders worldwide. METHODS: We developed a Markov decision tree for the economic evaluation of mass vaccination against COVID-19. The effectiveness of reducing outcomes after the administration of three COVID-19 vaccines (BNT162b2 (Pfizer-BioNTech), mRNA-1273 (Moderna), and AZD1222 (Oxford-AstraZeneca)) were modelled with empirical parameters obtained from literatures. The direct cost of vaccine and COVID-19 related medical cost, the indirect cost of productivity loss due to vaccine jabs and hospitalization, and the productivity loss were accumulated given different vaccination scenarios. We reported the incremental cost-utility ratio and benefit/cost (B/C) ratio of three vaccines compared to no vaccination with a probabilistic approach. RESULTS: Moderna and Pfizer vaccines won the greatest effectiveness among the three vaccines under consideration. After taking both direct and indirect costs into account, all of the three vaccines dominated no vaccination strategy. The results of B/C ratio show that one dollar invested in vaccine would have USD $13, USD $23, and USD $28 in return for Moderna, Pfizer, and AstraZeneca, respectively when health and education loss are considered. The corresponding figures taking value of the statistical life into account were USD $176, USD $300, and USD $443. CONCLUSION: Mass vaccination against COVID-19 with three current available vaccines is cost-saving for gaining more lives and less cost incurred.


Assuntos
COVID-19 , Vacinação em Massa , Vacina BNT162 , COVID-19/economia , COVID-19/prevenção & controle , Vacinas contra COVID-19/economia , ChAdOx1 nCoV-19 , Análise Custo-Benefício , Humanos , Vacinação em Massa/economia
19.
Intern Med J ; 51(4): 494-505, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33890372

RESUMO

BACKGROUND: To allow better allocation of staff and resources, rapid response teams attending to acutely deteriorating or aggressive patients with suspected or confirmed COVID-19 infection were pre-warned with the announcement of 'Code-95' with calls. AIM: To assess healthcare worker (HCW) perspectives on pre-warning rapid response calls (RRC) with 'Code-95' in announcements when attending to deteriorating or aggressive patients with suspected/confirmed COVID-19 infection. METHODS: Design: prospective cross-sectional single-centre survey of HCW over a 3-week period. SETTING: tertiary public hospital. PARTICIPANTS: HCW caring for deteriorating or aggressive patients. MAIN OUTCOME MEASURES: the primary outcome was to assess HCW perspectives in attending Code-95 calls. Secondary outcomes were to identify any differences related to craft group, age, experience or presence of comorbidities. RESULTS: A total of 297 responses was analysed; 86.7% of HCW (n = 257) attending Code-95 calls reported anxiety. Medical staff reported greater anxiety in comparison to nursing staff (93.8% vs 78.5%; P = 0.002). Efferent team reported higher anxiety in contrast to afferent team (92.6% vs 58.8%; P = 0.021). There was no significant difference in perceived anxiety based on age (≤40 vs >40 years of age), years of experience (≤5 vs >5 years), comorbidities or mental illness; 54% reported concerns about adequacy of infection-control policies and personal protective equipment; 45% were worried about inadequate training for responding to Code-95 calls. CONCLUSIONS: Most surveyed HCW supported Code-95 announcements pre-warning them of potential COVID-19 exposure when attending a RRC. However, the majority of HCW reported anxiety when attending these calls. Medical and efferent team HCW perceived greater anxiety compared to nursing and afferent team HCW. The Code-95 system to pre-warn rapid response teams may be a useful addition to protecting HCW from infectious diseases, although broader implementation will require greater resourcing, training and support.


Assuntos
COVID-19 , Adulto , Estudos Transversais , Pessoal de Saúde , Humanos , Percepção , Estudos Prospectivos , SARS-CoV-2
20.
Biomaterials ; 271: 120762, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33773400

RESUMO

Although traditional 3D scaffolds or biomimetic hydrogels have been used for tissue engineering and regenerative medicine, soft tissue microenvironment usually has a highly anisotropic structure and a dynamically controllable deformation with various biomolecule distribution. In this study, we developed a hierarchical hybrid gelatin methacrylate-microcapsule hydrogel (HGMH) with Neurotrophin-3(NT-3)-loaded PLGA microcapsules to fabricate anisotropic structure with patterned NT-3 distribution (demonstrated as striped and triangular patterns) by dielectrophoresis (DEP). The HGMH provides a dynamic biomimetic sinuate-microwrinkles change with NT-3 spatial gradient and 2-stage time-dependent distribution, which was further simulated using a 3D finite element model. As demonstrated, in comparison with striped-patterned hydrogel, the triangular-patterned HGMH with highly anisotropic array of microcapsules exhibits remarkably spatial NT-3 gradient distributions that can not only guide neural stem cells (NSCs) migration but also facilitate spinal cord injury regeneration. This approach to construct hierarchical 4D hydrogel system via an electromicrofluidic platform demonstrates the potential for building various biomimetic soft scaffolds in vitro tailed to real soft tissues.


Assuntos
Hidrogéis , Regeneração da Medula Espinal , Cápsulas , Engenharia Tecidual , Tecidos Suporte
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