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1.
J Formos Med Assoc ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38853047

RESUMO

AIMS: Managing proximal humerus pathologic fractures requires strategic planning to ensure optimal patient outcomes. Traditionally, fixation of the humerus using long devices has been considered the standard of care, but emerging evidence has challenged this approach. This study aimed to compare long plates (LPs) and intermediate-length plates (IPs) in this clinical context. METHODS: Forty-four patients with proximal humerus metastatic bone disease were retrospectively studied from 2013 to 2019, with 11 (25%) receiving long plates (LPs) and 33 (75%) intermediate-length plates (IPs). Outcomes included tumor progression, reoperation rates, postoperative anemia, blood loss, operation time, and hospitalization duration. Tumor progression was classified into three categories, with Type III progression (new metastatic lesions in the distal humerus) theoretically benefiting most from whole bone stabilization. RESULTS: Tumor progression occurred in three patients (7%), all of them was in IPs. No revision surgery was needed to address these tumor progressions, including one type III progression which occurred 34 months postoperatively after IP surgery. IP were associated with a reduced operation time compared with LP (median, 1.5 h [IQR, 1.2-1.9] vs. 2.4 [IQR, 1.7-2.5]; p = 0.004). No differences were found for the other perioperative outcomes. CONCLUSIONS: Our findings reveal a low incidence of tumor progression and low reoperation rates in both groups. The shortened operative time associated with IP use suggests its particular suitability for patients with limited life expectancy. Further research is needed to elucidate the ideal prosthesis length that best balances the risks and benefits when addressing proximal humerus metastatic disease.

2.
J Chin Med Assoc ; 87(7): 706-713, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38704660

RESUMO

BACKGROUND: The clinical and radiologic outcomes of the Oxford unicompartmental knee arthroplasty utilizing Microplasty® instrumentation have not been extensively investigated in Taiwanese patients. Despite the efficacy of this treatment for unicompartmental knee diseases, its specific impact on this population remains unknown. METHODS: We retrospectively analyzed prospectively collected data of patients who underwent OUKA with MP between 2018 and 2021, including demographic information, component position, preoperative and postoperative knee range of motion (ROM), numeric rating scale (NRS), and 2011 Knee Society Score-functional activity score (2011 KSS-FAS). We compared preoperative and postoperative data and analyzed the correlation between clinical and radiographic outcomes. RESULTS: Among 140 patients with an average age of 66.8 years, predominantly female, the majority exhibited components that fell within the radiographically acceptable tolerance ranges. The mean 2.5-year follow-up revealed significant improvements in knee ROM from 102.6° ± 12.9° to 127.3° ± 9.8° ( p < 0.05), pain reduction from 7.7 ± 0.8 to 0.4 ± 0.7 ( p < 0.001), and KSS-FAS from 30.7 ± 10.5 to 94.3 ± 5.2 ( p < 0.001). Notably, a tibial component medial overhang within tolerance predicted shorter hospital stays, and a higher preoperative KSS correlated with lower postoperative NRS. No independent variables were identified as predictors of a higher postoperative KSS. CONCLUSION: Our study on OUKA with MP in Taiwanese patients reveals promising early clinical and radiographic outcomes. Tibial component medial overhang <3 mm is associated with shorter hospital stays, and a higher preoperative KSS predicts lower NRS at 1 year postoperatively.


Assuntos
Artroplastia do Joelho , Humanos , Artroplastia do Joelho/métodos , Feminino , Masculino , Idoso , Estudos Retrospectivos , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Taiwan , Idoso de 80 Anos ou mais , Resultado do Tratamento
3.
JMIR Res Protoc ; 13: e55662, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38466979

RESUMO

BACKGROUND: In recent years, advancements in cancer treatment have enabled cancer cell inhibition, leading to improved patient outcomes. However, the side effects of chemotherapy, especially leukopenia, impact patients' ability to tolerate their treatments and affect their quality of life. Traditional Chinese medicine is thought to provide complementary cancer treatment to improve the quality of life and prolong survival time among patients with cancer. OBJECTIVE: This study aims to evaluate the effectiveness of Chinese herbal medicine (CHM) as a complementary treatment for neutropenia prevention and immunity modulation during chemotherapy in patients with breast cancer. METHODS: We will conduct a real-world pragmatic clinical trial to evaluate the effectiveness of CHM as a supplementary therapy to prevent neutropenia in patients with breast cancer undergoing chemotherapy. Patients will be classified into CHM or non-CHM groups based on whether they received CHM during chemotherapy. Using generalized estimating equations or repeated measures ANOVA, we will assess differences in white blood cell counts, absolute neutrophil counts, immune cells, and programmed cell death protein 1 (PD-1) expression levels between the 2 groups. RESULTS: This study was approved by the research ethics committee of Hualien Tzu Chi Hospital (IRB 110-168-A). The enrollment process began in September 2021 and will stop in December 2024. A total of 140 patients will be recruited. Data cleaning and analysis are expected to finish in the middle of 2025. CONCLUSIONS: Traditional Chinese medicine is the most commonly used complementary medicine, and it has been reported to significantly alleviate chemotherapy-related side effects. This study's findings may contribute to developing effective interventions targeting chemotherapy-related neutropenia among patients with breast cancer in clinical practice. TRIAL REGISTRATION: International Traditional Medicine Clinical Trial Registry ITMCTR2023000054; https://tinyurl.com/yc353hes. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/55662.

4.
ACS Nano ; 17(18): 17908-17919, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37676036

RESUMO

Only a minority of patients respond positively to cancer immunotherapy, and addressing this variability is an active area of immunotherapy research. Infiltration of tumors by immune cells is one of the most significant prognostic indicators of response and disease-free survival. However, the ability to noninvasively sample the tumor microenvironment for immune cells remains limited. Imaging in the near-infrared-II region using rare-earth nanocrystals is emerging as a powerful imaging tool for high-resolution deep-tissue imaging. In this paper, we demonstrate that these nanoparticles can be used for noninvasive in vivo imaging of tumor-infiltrating T-cells in a highly aggressive melanoma tumor model. We present nanoparticle synthesis and surface modification strategies for the generation of small, ultrabright, and biocompatible rare-earth nanocrystals necessary for deep tissue imaging of rare cell types. The ability to noninvasively monitor the immune contexture of a tumor during immunotherapy could lead to early identification of nonresponding patients in real time, leading to earlier interventions and better outcomes.


Assuntos
Melanoma , Metais Terras Raras , Nanopartículas , Humanos , Linfócitos T , Imunoterapia , Diagnóstico por Imagem , Nanopartículas/uso terapêutico , Microambiente Tumoral
5.
BMC Musculoskelet Disord ; 24(1): 553, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37408033

RESUMO

BACKGROUND: Preoperative prediction of prolonged postoperative opioid use (PPOU) after total knee arthroplasty (TKA) could identify high-risk patients for increased surveillance. The Skeletal Oncology Research Group machine learning algorithm (SORG-MLA) has been tested internally while lacking external support to assess its generalizability. The aims of this study were to externally validate this algorithm in an Asian cohort and to identify other potential independent factors for PPOU. METHODS: In a tertiary center in Taiwan, 3,495 patients receiving TKA from 2010-2018 were included. Baseline characteristics were compared between the external validation cohort and the original developmental cohorts. Discrimination (area under receiver operating characteristic curve [AUROC] and precision-recall curve [AUPRC]), calibration, overall performance (Brier score), and decision curve analysis (DCA) were applied to assess the model performance. A multivariable logistic regression was used to evaluate other potential prognostic factors. RESULTS: There were notable differences in baseline characteristics between the validation and the development cohort. Despite these variations, the SORG-MLA ( https://sorg-apps.shinyapps.io/tjaopioid/ ) remained its good discriminatory ability (AUROC, 0.75; AUPRC, 0.34) and good overall performance (Brier score, 0.029; null model Brier score, 0.032). The algorithm could bring clinical benefit in DCA while somewhat overestimating the probability of prolonged opioid use. Preoperative acetaminophen use was an independent factor to predict PPOU (odds ratio, 2.05). CONCLUSIONS: The SORG-MLA retained its discriminatory ability and good overall performance despite the different pharmaceutical regulations. The algorithm could be used to identify high-risk patients and tailor personalized prevention policy.


Assuntos
Artroplastia do Joelho , Transtornos Relacionados ao Uso de Opioides , Humanos , Analgésicos Opioides/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Aprendizado de Máquina , Algoritmos , Prescrições , Estudos Retrospectivos
6.
Asia Pac Allergy ; 13(1): 10-14, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37389101

RESUMO

Bronchiolitis is the most common seasonal viral respiratory disorder in infants. However, risk factors for the development of bronchiolitis, particularly during pregnancy, remain unclear. Methods: A questionnaire was administered to the parents of the hospitalized infants with acute bronchiolitis to obtain information regarding patients' medical, family, and prenatal exposure history. Logistic regression with adjustment was performed to evaluate risk factors associated with bronchiolitis in the infants. Results: Among the enrolled patients, 55 (36.7%) were diagnosed as having bronchiolitis, and the majority (89%) of the patients had moderate-to-severe bronchiolitis. The bronchiolitis group had lower C-reactive protein levels than did the control group. Fewer patients in the bronchiolitis group developed fever. However, hospital stays were longer in the bronchiolitis group than in the control group. Respiratory syncytial virus was the most detected virus (23/26, 88.6%) in the bronchiolitis group. Male sex (odds ratio [OR], 5.71; 95% confidence interval [CI], 2.02-16.12; P < 0.001), antibiotic usage during pregnancy (OR, 27.2; 95% CI, 1.12-660.84; P = 0.04), and viral infection (OR, 49.3; 95% CI, 9.01-270.26; P < 0.001) during the postnatal period were significantly associated with hospitalization for acute bronchiolitis in the infants. By contrast, pet exposure during the perinatal period was significantly and negatively associated with acute bronchiolitis (OR = 0.21, 95% CI = 0.07-0.69, P < 0.01). Conclusion: Environmental exposures during pregnancy may affect respiratory health in offspring, and effective strategies should be developed to prevent bronchiolitis in early life.

7.
J Microbiol Immunol Infect ; 56(4): 871-874, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36894477

RESUMO

From 2011, 37 children were referred to a hospital due to low levels of T cell receptor excision circles (TRECs) from newborn screening. Among them, three children were immunologically characterized and followed up to show that postnatal corticosteroid usage may be among the causes of false positivity in TRECs screening.


Assuntos
Triagem Neonatal , Imunodeficiência Combinada Severa , Recém-Nascido , Criança , Humanos , Imunodeficiência Combinada Severa/diagnóstico , DNA , Fatores de Risco , Receptores de Antígenos de Linfócitos T
8.
ACS Appl Mater Interfaces ; 15(12): 15279-15289, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36921119

RESUMO

Here, the successful transformation of graphitic carbon with a high degree of graphitization and a nanoflake structure from pyrolytic tire carbon black was demonstrated. First, amorphous carbon black with a porous structure was obtained after pyrolysis and simple preacid treatments. Subsequently, the carbon black was converted into a highly graphitic structure at a relatively low temperature (850 °C) through a facile electrochemical route using molten salt, which is ecofriendly and has high potential for large-scale graphitization compared to conventional incineration techniques. Moreover, we further improved the crystallinity and uniformity of the product simultaneously by directly mixing the metal oxide catalyst Fe2O3 with a carbon precursor. The mechanism of this metal-catalyzed electrochemical graphitization has been discussed in detail. To confirm their potential in practical applications, the as-prepared graphitized nanoflakes were used as conductive additives for silicon anodes in lithium-ion batteries, which showed a performance comparable to those utilizing commercial Super-P additives, exhibiting an initial Coulombic efficiency of approximately 79.7% and a high capacity retention of approximately 45.8% after 100 cycles with a reversible capacity of 1220 mAh g-1 at a current rate of 400 mA g-1. Hence, successfully recovered waste-tire-derived carbon black utilizing a low-temperature Fe2O3-catalyzed electrochemical process opens a pathway in low-temperature graphitization toward a sustainable value-added application in the field of energy storage.

9.
ACS Nano ; 16(8): 11676-11691, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35830573

RESUMO

M13 bacteriophage (phage) are versatile, genetically tunable nanocarriers that have been recently adapted for use as diagnostic and therapeutic platforms. Applying p3 capsid chlorotoxin fusion with the "inho" circular single-stranded DNA (cssDNA) gene packaging system, we produced miniature chlorotoxin inho (CTX-inho) phage particles with a minimum length of 50 nm that can target intracranial orthotopic patient-derived GBM22 glioblastoma tumors in the brains of mice. Systemically administered indocyanine green conjugated CTX-inho phage accumulated in brain tumors, facilitating shortwave infrared detection. Furthermore, we show that our inho phage can carry cssDNA that are transcriptionally active when delivered to GBM22 glioma cells in vitro. The ability to modulate the capsid display, surface loading, phage length, and cssDNA gene content makes the recombinant M13 phage particle an ideal delivery platform.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Camundongos , Animais , Glioblastoma/diagnóstico por imagem , Glioblastoma/genética , Glioblastoma/terapia , Bacteriófago M13 , Capsídeo , Proteínas do Capsídeo , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia
10.
ACS Nano ; 16(8): 12930-12940, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35849731

RESUMO

Short-wave infrared (SWIR; 850-1700 nm) upconversion fluorescence enables "autofluorescence-free" imaging with minimal tissue scattering, yet it is rarely explored due to the lack of strongly emissive SWIR upconversion fluorophores. In this work, we apply SWIR upconversion fluorescence for in vivo imaging with exceptional image contrast. Gold nanorods (AuNRs) are used to enhance the SWIR upconversion emission of small organic dyes, forming a AuNR-dye nanocomposite (NC). A maximal enhancement factor of ∼1320, contributed by both excitation and radiative decay rate enhancement, is achieved by varying the dye-to-AuNR ratio. In addition, the upconversion emission intensity of both free dyes and AuNR-dye NCs depends linearly on the excitation power, indicating that the upconversion emission mechanism remains unchanged upon enhancement, and it involves one-photon absorption. Moreover, the SWIR upconversion emission shows a significantly higher signal contrast than downconversion emission in the same emission window in a nonscattering medium. Finally, we apply the surface plasmon enhanced SWIR upconversion fluorescence for in vivo imaging of ovarian cancer, demonstrating high image contrast and low required dosage due to the suppressed autofluorescence.


Assuntos
Corantes Fluorescentes , Neoplasias Ovarianas , Humanos , Feminino , Fluorescência , Ouro , Diagnóstico por Imagem , Neoplasias Ovarianas/diagnóstico por imagem
11.
World Allergy Organ J ; 14(5): 100538, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34025904

RESUMO

BACKGROUND: Asthma is a common pediatric chronic respiratory disease worldwide. Previous studies showed the prevalence of childhood asthma increased in developed countries as well as in Taiwan in the late 20th century. Recently, several reports from different parts of the world showed a reversed trend in this epidemic of childhood asthma prevalence. This study investigated the trend of childhood asthma through serial cross-section questionnaire surveys in the southern part of Taiwan, and identified associated factors related to this trend in elementary school children. METHODS: We used the Chinese version of the International Study of Asthma and Allergies in Childhood (ISAAC)29 questionnaire to assess the asthma status of elementary school students aged 6-12 years in Tainan city in 3 independent study periods, namely, 2008-2009, 2010-2012, and 2017-2018. We assessed the trend of "asthma" and "related respiratory symptoms" across 3 study periods. RESULTS: Of the 19,633 respondents, 17,545 (89.4%) completed the questionnaires. After adjustment for covariates, the prevalence of asthma and related respiratory symptoms was significantly lower in 2017-2018 than in the 2 earlier periods. Among the protective factors, the increasing rate of breastfeeding might be partly responsible for the observed reduced prevalence of current asthma and exercise-induced wheeze, but not physician-diagnosed asthma. The presence of pets in the house was the risk factor that correlated with the prevalence of nocturnal cough. Pearson correlation analysis showed a significant correlation of the prevalence of physician-diagnosed asthma, current asthma, and exercise-induced wheezing with the concentrations of air pollutant particles with aerodynamic diameter ≤10 µM (PM10) (r = 0.84, 0.77 and 0.81, respectively). CONCLUSION: The prevalence of asthma and related respiratory symptoms has declined in elementary school-age children in southern Taiwan. The increased prevalence of breastfeeding, decreased rate of the presence of pets in the house, and improvement in outdoor air pollution seem to be related to this decreasing trend of asthma in school children. Our findings will provide the scientific base to empower prevention policy to reverse the trend of childhood asthma prevalence. TRIAL REGISTRATION: N/A.

12.
J Chin Med Assoc ; 84(7): 704-708, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33990516

RESUMO

BACKGROUND: In early 2020, a global outbreak of 2019 novel coronavirus disease (COVID-19) caused high mortality rates and public panic. Worldwide demand for personal protective equipment has risen, with diminishing supplies and shortages reported. During the pandemic, charitable donations have been made by the public, aimed at helping medical staff. Based on the open data, we investigate the charitable in-kind donations received by a large medical center in northern Taiwan (Taipei Veterans General Hospital [TPEVGH]) in Taiwan during the pandemic. METHODS: The period of investigation was the first half of the year 2020. TPEVGH has received various public donations. The list of donations published on the hospital's official website was analyzed. The variables in the analysis were donation category, donation percentage, number of donations, and total donation amount. RESULTS: Most in-kind donations were food and beverages (55.1%), with a monetary value of 3 124 510 New Taiwan Dollars (NTD) (24.3%). Medical equipment accounted for the second-highest number of items (34.8%) but was the highest monetary value (70.6%; 9 275 945 of 12 875 855 NTD). Daily necessities accounted for the lowest number of items (10.1%) and had a total monetary value of 475 400 NTD (3.7%). Over two-thirds were beverages (68.4%), all of which were bottles or cans for easy storage. Despite only five items (13.2%) being juice, the donation size was the largest, accounting for nearly half (47.1%) of the total monetary value. Only one item was fruit, which was high-class organic apples. The monetary value of this item was the highest (7.8%) among all donated food. Most donated snacks were biscuits. CONCLUSION: During the COVID-19 pandemic, most public donations to TPEVGH were food and daily necessities. While every donation should be appreciated, accepting high volumes of donations might incur donation management problems. Further research could be focused on managerial aspects, for example, quality and safety checking, storage, and distribution.


Assuntos
COVID-19/epidemiologia , SARS-CoV-2 , Bebidas , Instituições de Caridade/estatística & dados numéricos , Alimentos , Humanos , Equipamento de Proteção Individual , Taiwan/epidemiologia
13.
Adv Mater ; 33(7): e2006057, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33448062

RESUMO

Short-wave infrared (SWIR, 900-1700 nm) enables in vivo imaging with high spatiotemporal resolution and penetration depth due to the reduced tissue autofluorescence and decreased photon scattering at long wavelengths. Although small organic SWIR dye molecules have excellent biocompatibility, they have been rarely exploited as compared to their inorganic counterparts, mainly due to their low quantum yield. To increase their brightness, in this work, the SWIR dye molecules are placed in close proximity to gold nanorods (AuNRs) for surface plasmon-enhanced emission. The fluorescence enhancement is optimized by controlling the dye-to-AuNR number ratio and up to ≈45-fold enhancement factor is achieved. In addition, the results indicate that the highest dye-to-AuNR number ratio gives the highest emission intensity per weight and this is used for synthesizing SWIR imaging probes using layer-by-layer (LbL) technique with polymer coating protection. Then, the SWIR imaging probes are applied for in vivo imaging of ovarian cancer and the surface coating effect on intratumor distribution of the imaging probes is investigated in two orthotopic ovarian cancer models. Lastly, it is demonstrated that the plasmon-enhanced SWIR imaging probe has great potential for fluorescence imaging-guided surgery by showing its capability to detect sub-millimeter-sized tumors.


Assuntos
Materiais Biocompatíveis/química , Corantes Fluorescentes/química , Ouro/química , Nanotubos/química , Imagem Óptica/métodos , Neoplasias Ovarianas/diagnóstico por imagem , Animais , Melhoramento Biomédico , Linhagem Celular Tumoral , Feminino , Humanos , Raios Infravermelhos , Luciferases/química , Luciferases/genética , Camundongos Nus , Polímeros/química , Ondas de Rádio , Propriedades de Superfície , Distribuição Tecidual
14.
J Am Chem Soc ; 142(50): 21189-21196, 2020 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-33270453

RESUMO

Single-wall carbon nanotubes (SWCNTs) in liquid suspension have been observed to emit delayed, microsecond-scale fluorescence arising from upconverted triplet excitons that are directly created through energy transfer from singlet oxygen molecules (1O2). The singlet oxygen is produced through quenching of an optically excited organic sensitizer. The mechanism of this delayed fluorescence has been deduced from measurements of time-resolved emission kinetics, delayed emission spectra, and polarization-resolved excitation-emission spectra. The observed strong dependence of 1O2 sensitization efficiency on SWCNT structure suggests that (7,6) triplet excitons have an energy near 970 meV. The yields for E11T → E11S upconversion are found to be in the range of several percent. These yields increase with increasing temperature and decrease with increasing excitation intensities, reflecting thermal activation and triplet-triplet exciton annihilation processes.

15.
J Microbiol Immunol Infect ; 53(1): 99-105, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29551298

RESUMO

BACKGROUND: Patients with severe combined immunodeficiency (SCID), which is caused by genetic defects in immune-related genes involved in the development or activation of the adaptive immune system, often died in infancy due to severe infections before definite molecular diagnosis could be made. Although recent improvement in early diagnosis has been achieved by newborn screening, the genetic basis of many of the patients is still unknown. METHODS: Here we performed whole exome sequencing (WES) to investigate the underlying genetic causes of SCID in a proband identified with newborn screening. Inheritance of the mutation was confirmed with targeted sequencing of the parents. Homozygosity mapping from the WES was used to investigate the consanguinity of the parents. Immunoblotting was used to confirm the loss of expression of the mutant protein. RESULTS: A novel homozygous frameshift mutation of IL7R was identified through WES. Both parents are carriers for this 1-bp deletion. HLA typing and exome-wide homozygous stretch mapping suggested that the parents are consanguineous. Immunoblotting showed no expression of IL7Rα isoform in the whole blood sample of the proband. The proband received peripheral blood stem cell transplantation and her general condition became stable. Our results suggest that IL7R is essential for T cell development but dispensable for the development of certain human NK cells B cells and suggest that WES can be a useful tool for precise genetic diagnosis of SCID following newborn screening in the index patient without the need to screen other members of the whole family.


Assuntos
Sequenciamento do Exoma , Mutação da Fase de Leitura , Subunidade alfa de Receptor de Interleucina-7/genética , Imunodeficiência Combinada Severa/genética , Consanguinidade , Feminino , Homozigoto , Humanos , Recém-Nascido , Triagem Neonatal , Linhagem , Análise de Sequência de DNA
16.
Anal Chem ; 91(19): 12484-12491, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31483990

RESUMO

Time-resolved measurements of short-wave infrared (SWIR) photoluminescence on the submicrosecond to millisecond scale are needed for physical and chemical studies involving singlet oxygen, single-walled carbon nanotubes, and other samples with weak, slow emission. We present here an alternative to the common method of time-correlated single photon counting (TCSPC) that is well suited to indium gallium arsenide avalanche photodiode (APD) detectors operated in Geiger mode. In the new method, termed synchro-excited free-running single photon counting (SEFR-SPC), excitation pulses from inexpensive laser diodes (providing a variety of wavelengths) are synchronized to detection events from a free-running detector covering the 900 to 1700 nm range. In contrast to traditional TCSPC, data from this method can be rigorously corrected for pile-up distortions, allowing operation with high excitation powers and low repetition rates. A technique is described to extend the system's dynamic range to approximately 108. We also show that SEFR-SPC provides state-of-the-art sensitivity in the SWIR spectral region and that spectrally filtered kinetic data can offer additional insights. A six-step correction protocol has been developed and implemented as a LabVIEW program for very accurate acquisition of kinetic shapes. The SEFR-SPC method will be a valuable tool for studies of weak, long-lived emission sources.

17.
Nat Commun ; 10(1): 2874, 2019 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253811

RESUMO

Covalent doping of single-walled carbon nanotubes (SWCNTs) can modify their optical properties, enabling applications as single-photon emitters and bio-imaging agents. We report here a simple, quick, and controllable method for preparing oxygen-doped SWCNTs with desirable emission spectra. Aqueous nanotube dispersions are treated at room temperature with NaClO (bleach) and then UV-irradiated for less than one minute to achieve optimized O-doping. The doping efficiency is controlled by varying surfactant concentration and type, NaClO concentration, and irradiation dose. Photochemical action spectra indicate that doping involves reaction of SWCNT sidewalls with oxygen atoms formed by photolysis of ClO- ions. Variance spectroscopy of products reveals that most individual nanotubes in optimally treated samples show both pristine and doped emission. A continuous flow reactor is described that allows efficient preparation of milligram quantities of O-doped SWCNTs. Finally, we demonstrate a bio-imaging application that gives high contrast short-wavelength infrared fluorescence images of vasculature and lymphatic structures in mice injected with only ~100 ng of the doped nanotubes.

18.
Small ; 15(28): e1901233, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31131998

RESUMO

Fluorescence imaging is a powerful tool for studying biologically relevant macromolecules, but its applicability is often limited by the fluorescent probe, which must demonstrate both high site-specificity and emission efficiency. In this regard, M13 virus, a versatile biological scaffold, has previously been used to both assemble fluorophores on its viral capsid with molecular precision and to also target a variety of cells. Although M13-fluorophore systems are highly selective, these complexes typically suffer from poor molecular detection limits due to low absorption cross-sections and moderate quantum yields. To overcome these challenges, a coassembly of the M13 virus, cyanine 3 dye, and silver nanoparticles is developed to create a fluorescent tag capable of binding with molecular precision with high emissivity. Enhanced emission of cyanine 3 of up to 24-fold is achieved by varying nanoparticle size and particle-fluorophore separation. In addition, it is found that the fluorescence enhancement increases with increasing dye surface density on the viral capsid. Finally, this highly fluorescent probe is applied for in vitro staining of E. coli. These results demonstrate an inexpensive framework for achieving tuned fluorescence enhancements. The methodology developed in this work is potentially amendable to fluorescent detection of a wide range of M13/cell combinations.


Assuntos
Bacteriófago M13/metabolismo , Carbocianinas/química , Fluorescência , Nanopartículas Metálicas/ultraestrutura , Tamanho da Partícula , Polietilenoglicóis/química , Prata/química
19.
Sci Rep ; 9(1): 3873, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30846704

RESUMO

Detection of biological features at the cellular level with sufficient sensitivity in complex tissue remains a major challenge. To appreciate this challenge, this would require finding tens to hundreds of cells (a 0.1 mm tumor has ~125 cells), out of ~37 trillion cells in the human body. Near-infrared optical imaging holds promise for high-resolution, deep-tissue imaging, but is limited by autofluorescence and scattering. To date, the maximum reported depth using second-window near-infrared (NIR-II: 1000-1700 nm) fluorophores is 3.2 cm through tissue. Here, we design an NIR-II imaging system, "Detection of Optically Luminescent Probes using Hyperspectral and diffuse Imaging in Near-infrared" (DOLPHIN), that resolves these challenges. DOLPHIN achieves the following: (i) resolution of probes through up to 8 cm of tissue phantom; (ii) identification of spectral and scattering signatures of tissues without a priori knowledge of background or autofluorescence; and (iii) 3D reconstruction of live whole animals. Notably, we demonstrate noninvasive real-time tracking of a 0.1 mm-sized fluorophore through the gastrointestinal tract of a living mouse, which is beyond the detection limit of current imaging modalities.


Assuntos
Imagem Óptica/instrumentação , Imagem Óptica/métodos , Tecido Adiposo/diagnóstico por imagem , Algoritmos , Animais , Encéfalo/diagnóstico por imagem , Mama/diagnóstico por imagem , Bovinos , Desenho de Equipamento , Corantes Fluorescentes , Trato Gastrointestinal/diagnóstico por imagem , Humanos , Imageamento Tridimensional/instrumentação , Imageamento Tridimensional/métodos , Camundongos Nus , Músculos/diagnóstico por imagem , Imagens de Fantasmas , Pele/diagnóstico por imagem
20.
J Chin Med Assoc ; 82(5): 424-427, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30893265

RESUMO

BACKGROUND: Taiwan's NHI Administration proposed a nationwide postacute care-cerebral vascular disease (PAC-CVD) program, which transfers stroke patients at postacute phase in medical centers to community hospitals. Its aim is mainly to prevent a prolonged stay in medical centers, which usually results in higher medical costs. The present study evaluated the 3-months functional outcomes of stroke patients receiving PAC-CVD. METHODS: We retrogradely retrieved patients' data from Stroke Registry of a Northern medical center. Patients admitted between January 2014 and March 2018 were screened. We included patients receiving PAC-CVD and age/sex/stroke severity/functional status-matched acute stroke patients (regular rehabilitation group). Baseline clinical characteristics and 3-months functional outcomes were analyzed. We defined 3-months mRS 0 to 2 as better, 3 to 4 as same, and 5 to 6 as worse functional recovery. RESULTS: One-hundred-and-seventy-three patients receiving PAC-CVD and 173 matched controls (68.2 ± 14.0-years-old, 68.5% ± 11.22% men) were recruited. All patients were with mRS 3 to 4 at discharge from our medical center. The distributions of 3-months functional recovery in two groups were as follows: better/same/worse 3-months functional outcomes, PAC-CVD = 40.4%/57.8%/1.8%; controls (regular rehabilitation) = 33.9%/50.3%/5.8%. Multivariate analyses adjusted for age, sex, NIHSS, and cardiovascular risk factors were performed to evaluate whether PAC-CVD predicted better or poor functional outcomes. The results showed that compared with controls, PAC-CVD group had similar frequency of better functional recovery (odds ratio [OR] = 0.97, 95% CI = 0.54-1.74, p = 0.924) but less frequency of worse functional outcomes (OR = 0.08, 95% CI = 0.008-0.84, p = 0.035). CONCLUSION: About one-third of patients with mRS 3 to 4 recovered well in 3-months after stroke in both PAC-CVD and regular rehabilitation groups. Our results showed that PAC-CVD program can significantly decrease functional decline after acute stroke.


Assuntos
Recuperação de Função Fisiológica , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/terapia , Cuidados Semi-Intensivos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Acidente Vascular Cerebral/fisiopatologia
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