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1.
J Biophotonics ; 17(4): e202300422, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38211977

RESUMO

Multiphoton microscopy (MPM) enables deep brain imaging. Three optical windows: NIR-I, NIR-II, and NIR-III are widely used. Recently, NIR-IV (the 2200 nm window) has been demonstrated to be the last and longest window for deep tissue MPM. However, so far MPM covers only two optical windows labeled by single fluorescent probe, one for emission and one for excitation. Here we demonstrate in vivo deep brain MPM covering three optical windows, with emission at NIR-I, NIR-II, and excitation at NIR-IV, labeled by ICG. The innovations include: (1) characterizing both 3-photon excitation and emission properties of ICG emitting at both NIR-I and NIR-II, in water, plasma, and circulating blood; (2) a home-built multiphoton microscope with simultaneous dual channel detection, with which we demonstrate deep brain MPM 950 µm (NIR-I) and 850 µm (NIR-II) into the mouse brain in vivo, verifying that multi-optical window MPM is promising for deep brain imaging.


Assuntos
Encéfalo , Microscopia de Fluorescência por Excitação Multifotônica , Camundongos , Animais , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Encéfalo/diagnóstico por imagem , Corantes Fluorescentes , Imagem Óptica/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos
2.
Huan Jing Ke Xue ; 44(4): 1998-2008, 2023 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-37040950

RESUMO

Focused on the key areas of energy, buildings, industry, and transportation, with 2020 as the base year and 2035 as the target year, we respectively designed the baseline scenario, policy scenario, and enhanced scenario, calculated the emission reduction potential of air pollutants and CO2 of Beijing, and constructed an assessment method of co-control effect gradation index to evaluate the co-control effect of air pollutants and CO2 in the policy scenario and enhanced scenario. The results showed that in the policy scenario and enhanced scenario, the reduction rates of air pollutants emissions will reach 11%-75% and 12%-94%, respectively, and reduction rates of CO2 emissions will reach 41% and 52%, respectively, compared with those from the baseline scenario. Optimizing vehicle structure had the largest contribution to the emission reduction of NOx, VOCs, and CO2, and the emission reduction rates will reach 74%, 80%, and 31% in the policy scenario and 68%, 74%, and 22% in the enhanced scenario, respectively. Replacing coal-fired with clean energy in rural areas had the largest contribution to the emission reduction of SO2; the emission reduction rates will reach 47% and 35% in the policy scenario and enhanced scenario, respectively. Improving the green level of new buildings had the largest contribution to the emission reduction of PM10; the emission reduction rates will reach 79% and 74% in the policy scenario and enhanced scenario, respectively. Optimizing travel structure and promoting green development of digital infrastructure had the best co-control effect. The co-control effect of replacing coal-fired with clean energy in rural areas, optimizing vehicle structure, and promoting green upgrading of the manufacturing industry will be improved to a better status in the enhanced scenario. More attention should be paid to improving the proportion of green trips, implementing the promotion of new energy vehicles, and the green transportation of goods to reduce emissions in the field of transportation. At the same time, with the continuous improvement in electrification level in the end energy consumption structure, the proportion of green electricity should be increased by expanding local renewable energy power production and increasing external green electricity transmission capacity, to enhance the co-control effect of pollution and carbon reduction.

3.
ACS Nano ; 17(4): 3686-3695, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36799427

RESUMO

Multiphoton microscopy (MPM) is an enabling technology for visualizing deep-brain structures at high spatial resolution in vivo. Within the low tissue absorption window, shifting to longer excitation wavelengths reduces tissue scattering and boosts penetration depth. Recently, the 2200 nm excitation window has emerged as the last and longest window suitable for deep-brain MPM. However, multiphoton fluorescence imaging at this window has not been demonstrated, due to the lack of characterization of multiphoton properties of fluorescent labels. Here we demonstrate technologies for measuring both the multiphoton excitation and emission properties of fluorescent labels at the 2200 nm window, using (1) 3-photon (ησ3) and 4-photon action cross sections (ησ4) and (2) 3-photon and 4-photon emission spectra both ex vivo and in vivo of quantum dots. Our results show that quantum dots have exceptionally large ησ3 and ησ4 for efficient generation of multiphoton fluorescence. Besides, the 3-photon and 4-photon emission spectra of quantum dots are essentially identical to those of one-photon emission, which change negligibly subject to the local environment of circulating blood. Based on these characterization results, we further demonstrate deep-brain vasculature imaging in vivo. Due to the superb multiphoton properties of quantum dots, 3-photon and 4-photon fluorescence imaging reaches a maximum brain imaging depth of 1060 and 940 µm below the surface of a mouse brain, respectively, which enables the imaging of subcortical structures. We thus fill the last gap in multiphoton fluorescence imaging in terms of wavelength selection.


Assuntos
Pontos Quânticos , Animais , Camundongos , Pontos Quânticos/química , Encéfalo/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Corantes Fluorescentes/química , Imagem Óptica
4.
J Biophotonics ; 16(5): e202200365, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36633161

RESUMO

The brain arteriolar wall is a multilayered structure, whose integrity is of key significance to the brain function. However, resolving these different layers in anmial models in vivo is hampered by the lack of either labeling or imaging technology. Here, we demonstrate that three-photon microscopy (3PM) is an ideal solution. In mouse brain in vivo, excited at the 1700-nm window, label-free third-harmonic generation imaging and three-photon fluorescence (3PF) imaging with Alexa 633 labeling colocalize and resolve the internal elastic lamina. Furthermore, Alexa Fluor 594-conjugated Wheat Germ Agglutinin (WGA-594) shows time-dependent labeling behavior. As time lapses, WGA-594 first labels endothelium, and then vascular smooth muscle cells, which are readily captured and resolved with 3PF imaging. Our results show that 3PM, in combination with proper labeling, is a promising technology for investigating the structures of brain arteriolar wall in vivo.


Assuntos
Encéfalo , Microscopia de Fluorescência por Excitação Multifotônica , Camundongos , Animais , Encéfalo/diagnóstico por imagem , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Endotélio
5.
China Occupational Medicine ; (6): 230-234, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-996554

RESUMO

Carbon nanotube (CNT), as a new nanomaterial, is widely used in commercial and industrial production. The occupational exposure of workers involved in CNT production and manufacturing is gradually increasing. CNT mainly enters the human body through the respiratory system, and mainly exerts toxic effects on the respiratory system, including decreased lung function, lung inflammation, and pulmonary fibrosis. Pulmonary fibrosis, as one of the important diseases caused by CNT exposure, has attracted attention and been studied. The process of pulmonary fibrosis induced by CNT has four stages: acute pulmonary inflammatory response, structural destruction and parenchymal injury of lung tissue, impaired lung tissue repair and pulmonary fibrosis. The molecular mechanisms of CNT induced pulmonary fibrosis may be related to cell proliferation, epithelial-mesenchymal transition, fibroblast-myofibroblast differentiation, pulmonary inflammation, immune response and oxidative stress. In the future, it is needed to explore the pathogenesis of pulmonary fibrosis caused by CNT through animal experiments, and carry out large sample and multi-center epidemiological studies for verification.

6.
Chinese Journal of Orthopaedics ; (12): 550-558, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-993475

RESUMO

Objective:To investigate the efficacy of oblique lumbar interbody fusion (OLIF) combined with percutaneous transforaminal endoscopic decompression (PTED) and posterior pedicle fixation through Wiltse approach in the treatment of lumbar spondylolisthesis accompanied with lumbar spinal stenosis.Methods:From June 2017 to February 2022, 103 patients (50 males and 53 females) of lumbar spondylolisthesis accompanied with lumbar spinal stenosis were performed with OLIF combined with PTED and posterior pedicle fixation. The mean age was 64.1±5.2 years (range, 42-87 years). All involved cases were single-segment and included 83 cases of L 4, 5, 17 cases of L 3, 4, and 3 cases of L 2, 3. Among them, 94 cases were performed for the first time, and other 9 were revision surgery treated by posterior lumbar laminectomy previously. The visual analog scale (VAS) was used to evaluate the low back pain and leg pain, and the Oswestry disability index (ODI) was used to evaluate the lumbar function. The VAS and ODI scores were recorded respectively before the operation, at discharge, 1, 3, 6 months after the operation and at the last follow-up. Macnab criteria was used to evaluate the clinical efficacy at the last follow-up. At the same time, imaging measurements were conducted, including the anterior and posterior disc height, segmental lordotic angle, percentage of slip on lateral X-ray film and the vertebral canal area on axial MRI before and after surgery. Results:All of 103 patients were successfully operated in one stage with an average operation time of 177.7±21.5 min (range, 155-220 min), and an average intraoperative blood loss of 55.9±18.3 ml (range, 30-150 ml). The mean follow-up time were 15.1±2.6 months (range, 6-36 months). There were significant differences in both VAS scores of back and leg and ODI scores at each postoperative time point when compared with preoperative ( F=508.25, F=1524.82, F=1148.68, P<0.001). Macnab criteria of the last follow-up was evaluated as follow: excellent in 85 cases, good in 14, fair in 4, and the excellent and good rate was 96.1%. The radiographic results showed the mean immediate postoperative anterior disc height, posterior disc height, segmental lordotic angle, percentage of slip and axial area of the vertebral canal were 15.23±2.97 mm, 9.32±2.31 mm, 14.36°±4.18°, 3.89%±3.11%, 113.37±47.27 mm 2, and thus all of those increased significantly compared to the mean preoperative 11.93±3.17 mm, 7.21±2.03 mm, 6.15°±3.99°, 23.66%±7.79%, 57.63±28.91 mm 2, respectively ( t=7.84, t=7.07, t=14.91, t=27.62, t=9.68, P<0.001). All cases achieved bony fusion during 6-12 months after operation. The incidence of surgery-related complications was 10.7% (11/103). There were 3 cases of end plate fracture and 2 cases of dural injury, which had no complaint after operation. There was 1 case of pedicle screw entering into the spinal canal by mistake, and the symptoms of nerve damage appeared after operation. After 1 year it basically returned to normal. There were 2 cases of thigh numbness and 1 case of psoas major weakness after operation, all of which relieved after 4 weeks. There was 1 case continuous pain of abdominal incision after surgery. There was 1 case of cage subsidence at the last follow-up. Conclusion:OLIF combined with PTED and posterior pedicle fixation through Wiltse approach is a minimally invasive surgical method for the treatment of lumbar spondylolisthesis accompanied with lumbar spinal stenosis. With the combined minimally invasive techniques, the decompression, fusion and fixation of the lumbar spine can be fulfilled perfectly. It has the advantages of minimally invasive, good clical outcome, few complications and rapid rehabilitation.

7.
Chinese Journal of Neonatology ; (6): 283-288, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-990755

RESUMO

Objective:To summarize the clinical features and pathogenic gene mutation of Galloway-Mowat syndrome (GAMOS).Methods:We retrospectively collected the medical history, physical signs, laboratory findings, imaging, and molecular data of GAMOS in an infant diagnosed at the department of Pediatrics of Women and Children's Hospital, School of Medicine, Xiamen university. Relevant literature up to December 2021, retrieved from PubMed, Embase, Web of Science, the Cochrane Library, China National Knowledge Infrastructure, VIP, Wanfang and the Chinese Medical Journal Full Text database with the terms of "Galloway-Mowat syndrome", "infant", "WDR73", "LAGE3", "OSGEP", "TP53RK" and "TPRKB".Results:The male infant with dysmorphic facial features and microcephaly at birth gradually displayed growth restriction and developmental delay. He was admitted to hospital at 3 months and 1 day due to "tachypnea for a half day", and suffered from severe pneumonia, urinary tract infection, nephrotic syndrome, repetitive convulsion, septic shock, disseminated intravascular coagulation, acute renal damage and multiple organ failure during hospitalization. He died when his family had given up treatment. Whole exome sequencing revealed a homozygous mutation c.740G>A (p.Arg247Gln) in the OSGEP gene and both of his parents were heterozygous variation carriers. In the total 14 publications (13 were in English and only 1 in Chinese) that were retrieved, with 78 patients from 58 pedigrees. Together with the index case, there were 79 patients in total. The main clinical manifestations were craniofacial and skeletal dysmorphism, as well as nervous system, renal and eye impairment. Obstetric problems were detected in 15 cases (19.0%), including intrauterine growth restriction, microcephaly, oligohydramnios and fetal distress in utero. 49 cases (62.0%) died when reported. The genetic cause of GAMOS had been reported in 79 patients: OSGEP in 36 (45.6%), WDR73 in 29 (36.7%), TP53RK in 7(8.9%), LAGE3 in 5 (6.3%), and TPRKB in 2(2.5%).Conclusions:The main clinical manifestations of GAMOS were craniofacial and skeletal dysmorphism, development delay, leukoencephalopathy, myelination defect, proteinuria and nephrotic syndrome, and associated with poor prognosis. Prenatal findings may be useful for an early diagnosis.

8.
Chinese Pharmacological Bulletin ; (12): 844-850, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1013797

RESUMO

Aim To clarify the regulatory effect of Artesunate(ART) on tumor cell function and cell cycle in the pathological process of esophageal squamous cell carcinoma(ESCC). Methods KYSE450 and TE14 cells were treated with different concentrations of ART. The cells treated with 0 mg •L

9.
Chinese Pharmacological Bulletin ; (12): 1675-1681, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1013719

RESUMO

Aim To explore the effect of artesunate (ART) on the function of breast cancer cells during the progression of breast cancer and the possible mechanism of action. Methods MCF-7 (30 μmol • L-

10.
Singapore medical journal ; : 209-213, 2022.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-927275

RESUMO

INTRODUCTION@#Usage of metformin is associated with improved survival in lung, breast and prostate cancer, and metformin has been shown to inhibit cancer cell growth and proliferation in in vitro studies. Given the lack of clinical data on metformin use in patients with bladder cancer, we aimed to evaluate the role of metformin in their oncological outcomes.@*METHODS@#Medication use data from a prospectively maintained database of 122 patients with non-muscle-invasive bladder cancer treated with intravesical Bacille Calmette-Guerin (BCG), who were recruited under a randomised, double-blinded, controlled clinical trial, was collected and analysed. Kaplan-Meier curves were used to assess overall survival (OS) and disease-specific survival (DSS).@*RESULTS@#At a median follow-up duration of 102 (range 3-357) months, 53 (43.4%) patients experienced disease recurrence and 21 (17.2%) experienced disease progression. There was no significant difference in mortality between patients with and without diabetes mellitus. There was significant difference in OS between patients without diabetes mellitus, patients with diabetes mellitus on metformin and patients with diabetes mellitus but not on metformin (p = 0.033); patients with diabetes mellitus on metformin had the best prognosis. Metformin use was associated with significantly lower DSS (p = 0.042). Other oral hypoglycaemic agents, insulin or statins were not associated with disease recurrence or progression.@*CONCLUSION@#Metformin use was associated with improved oncological outcomes in patients with non-muscle-invasive bladder cancer treated with intravesical BCG. Prospective studies with larger patient populations are needed to validate the role of metformin as potential therapy for bladder cancer.


Assuntos
Humanos , Masculino , Adjuvantes Imunológicos/uso terapêutico , Administração Intravesical , Vacina BCG/uso terapêutico , Diabetes Mellitus , Progressão da Doença , Metformina/uso terapêutico , Invasividade Neoplásica , Recidiva Local de Neoplasia , Estudos Prospectivos , Estudos Retrospectivos , Neoplasias da Bexiga Urinária/tratamento farmacológico
11.
Biomed Opt Express ; 12(10): 6474-6484, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34745750

RESUMO

Visualization of lymphatic vessels is key to the understanding of their structure, function, and dynamics. Multiphoton microscopy (MPM) is a potential technology for imaging lymphatic vessels, but tissue scattering prevents its deep penetration in skin. Here we demonstrate deep-skin MPM of the lymphatic vessels in mouse hindlimb in vivo, excited at the 1700 nm window. Our results show that with contrast provided by indocyanine green (ICG), 2-photon fluorescence (2PF) imaging enables noninvasive imaging of lymphatic vessels 300 µm below the skin surface, visualizing both its structure and contraction dynamics. Simultaneously acquired second-harmonic generation (SHG) and third-harmonic generation (THG) images visualize the local environment in which the lymphatic vessels reside. After removing the surface skin layer, 2PF and THG imaging visualize finer structures of the lymphatic vessels: most notably, the label-free THG imaging visualizes lymphatic valves and their open-and-close dynamics in real time. MPM excited at the 1700-nm window thus provides a promising technology for the study of lymphatic vessels.

12.
Rev Sci Instrum ; 92(5): 055102, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243303

RESUMO

Rock burst early warning technology is currently applied mainly in microseismic monitoring. Rock burst signals indicate the micro-fracture phenomena of a rock and can transmit earthquake waves through the rock before they are finally received by a detector. A characteristic decomposition of rock micro-fracture signals was conducted by the singular value Empirical Mode Decomposition (EMD) algorithm to effectively decompose the characteristic signals of a rock micro-fracture from mixed microseismic signals, with a low signal to noise ratio to ensure prediction precision. When comparing the proposed method with wavelet decomposition and EMD, it was found that the local characteristics of the signals were retained effectively. The proposed algorithm was verified by applying it in a laboratory simulation and to the decomposition of microseismic signals from a hydro-power station. It was concluded that the improved algorithm had a better decomposition precision than wavelet decomposition and EMD decomposition and could effectively separate the characteristic signals of micro-earthquakes. This could provide a significant basis for the identification of the abnormal microseismic signals of rock micro-fractures as well as a pre-warning of rock fractures. It is therefore of practical significance to study rock fracture early warning technology.

13.
J Biophotonics ; 14(10): e202100076, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34160142

RESUMO

Multiphoton microscopy (MPM) excited at the 1700-nm window has enabled deep-tissue penetration in biological tissue, especially brain. MPM of skin may also benefit from this deep-penetration capability. Skin is a layered structure with varying refractive index (from 1.34 to 1.5). Consequently, proper immersion medium should be selected when imaging with high numerical aperture objective lens. To provide guidelines for immersion medium selection for skin MPM, here we demonstrate comparative experimental investigation of deep-skin MPM excited at 1600 nm in vivo, using both silicone oil and deuterium dioxide (D2 O) immersion. We specifically characterize imaging depths, signal levels and spatial resolution. Our results show that both immersion media give similar performance in imaging depth and spatial resolution, while signal levels are slightly better with silicone oil immersion. We also demonstrate that local injection of fluorescent beads into the skin is a viable technique for spatial resolution characterization in vivo.


Assuntos
Microscopia de Fluorescência por Excitação Multifotônica , Óleos de Silicone , Deutério , Imersão , Pele/diagnóstico por imagem
14.
J Biophotonics ; 14(3): e202000349, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33179837

RESUMO

3-photon microscopy (3PM) excited at the 1700 nm window enables deep-tissue imaging in vivo, especially in brain. PC rod soliton source has previously been exclusively used as the excitation source, which is rather costly and difficult to align. Here we demonstrate a novel nonlinear optical technique to build femtosecond laser source at the 1700 nm window, based on self-phase modulation (SPM) in a short span of large-mode-area fiber. The spectral broadening experienced by the pump pulse leads to the generation of a red-shifted sidelobe at 1603 nm. After spectral filtering, this sidelobe corresponds to 170-fs, 167-nJ pulses at 1603 nm. Using this SPM source, we further demonstrate deep-brain 3 PM to a depth of 1500 µm below the mouse brain surface in vivo. Our SPM femtosecond laser source thus provides a cost effective and easy-to-align alternative excitation source to the PC rod soliton source.


Assuntos
Microscopia , Fótons , Animais , Encéfalo/diagnóstico por imagem , Lasers , Camundongos
15.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-907806

RESUMO

Objective:To evaluate clincal value of preoperative peripheral blood CD4/CD8 and neutrophil to lymphocyte ratio (NLR) in papillary thyroid carcinoma (PTC) coexisted with Hashimoto’s thyroiditis (HT) .Methods:Clinicopathological data of 202 patients diagnosed as PTC treated with operation from Jul.2016 to Jun.2019 were retrospectively analyzed. They were divided into Treatment Group including 94 PTC coexisted with HT and Control Group including 108 thyroid cancer according to the postoperateive pathology report. CD4+ and CD8+ subsets in peripheral blood were analyzed by flowcytometer and blood counts were measured before surgery.Results:There was no significant difference in gender, tumor size, number of lesions or lymph node metastasis between the two goups. In comparison with Control Group, median age was lower (39.5 vs 50.5, P=0.001) and CD4/CD8 raito (1.9731.973 Cvs 1.24141973 CD P=0.001) was higher in Treatment group. There was a higher proportion of bilateral lobe thyroidectomy in Treatment Group (40/94 vs 26/108, P=0.005) . A multivariate model analysis identified CD4/CD8 raito as independent risk factor for incidence of PTC coexisted with HT [ OR=0.035, 95% CI (0.009-0.093) , P=0.001]. The NLR level of thyroid cancer patients was correlated with lateral lymph node metastasis negatively (correlation coefficients=-0.286, P=0.045) . Conclusions:PTC might have some connection with HT mediated by body inmune status. Preoperative NLR level is correlated with lateral lymph node metastasis.

16.
J Biophotonics ; 13(12): e202000321, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32969170

RESUMO

Myelin is a key component of the peripheral nervous system, whose structure anomaly in the digital skin is implicated in neuropathy. Here we demonstrate an in vivo labeling and imaging technique, capable of visualizing myelin sheaths deep in the mouse digital skin. Through material characterization, we verify that 3-photon fluorescence (3PF) can be generated from a commonly used dye- FluoroMyelin Red for labeling myelin, excited at the 1700-nm window. Topical injection of FluoroMyelin Red in the mouse digit leads to bright labeling of myelin sheaths. Harnessing the deep-penetration capability of 3-photon microscopy excited at the 1700-nm window, we demonstrate that 3PF imaging of FluoroMyelin Red-labeled myelin sheaths in the mouse digit in vivo can be achieved to a depth 340 µm below the skin surface, revealing both branching bundle of and individual myelin sheaths.


Assuntos
Microscopia , Bainha de Mielina , Animais , Camundongos , Fótons
17.
Opt Lett ; 45(18): 5271-5274, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32932509

RESUMO

Microglia act as the first and main form of active immune defense in brain. However, in animal models, research on these cells is limited to the superficial layer of the brain, due to the lack of a deep-imaging technique. Here we break this depth limit using three-photon fluorescence (3PF) microscopy excited at the 1700-nm window. Three-photon action cross-section (ησ3) measurement lays the basis for dye selection and the resultant maximization of 3PF generation. 3PF imaging suppresses the surface background, leading to a much improved signal-to-background ratio compared to the commonly used two-photon microscopy (2PM). We can image microglia 1124 µm below the brain surface in vivo, 3.7 times deeper than previous results using 2PM for microglia imaging. This technique enables us to visualize microglia in the white matter layer in vivo for the first time.


Assuntos
Encéfalo/citologia , Encéfalo/diagnóstico por imagem , Microglia/citologia , Microscopia de Fluorescência por Excitação Multifotônica , Animais , Camundongos , Razão Sinal-Ruído
18.
Biomed Opt Express ; 11(5): 2738-2744, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32499956

RESUMO

Measurement of the hemodynamic physical parameter blood flow speed in the brain in vivo is key to understanding brain physiology and pathology. 2-photon fluorescence microscopy with single blood vessel resolution is typically used, which necessitates injection of toxic fluorescent dyes. Here we demonstrate a label-free nonlinear optical technique, third-harmonic generation microscopy excited at the 1700-nm window, that is promising for such measurement. Using a simple femtosecond laser system based on soliton self-frequency shift, we can measure blood flow speed through the whole cortical grey matter, even down to the white matter layer. Together with 3-photon fluorescence microscopy, we further demonstrate that the blood vessel walls generate strong THG signals, and that plasma and circulating blood cells are mutually exclusive in space. This technique can be readily applied to brain research.

19.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20034215

RESUMO

BackgroundThe outbreak of coronavirus disease 2019 (COVID-19) initially appeared and has most rapidly spread in Wuhan, China. The case fatality rate is the most direct indicator to assess the hazards of an infectious disease. We aimed to estimate the instant fatality rate and cure rate of COVID-19 in Wuhan City and its affiliated Hubei Province. MethodsWe collected the daily case notification data of COVID-19 from Dec 8, 2019 to Mar 10, 2020 in Wuhan City and Hubei Province officially announced by the Chinese authority. The numbers of daily confirmed/deaths/cured cases and the numbers of daily cumulative confirmed/deaths/cured cases were obtained. The death time and cure time of COVID-19 patients were calculated based on the dates of diagnosis, death and discharge of individual cases. Then the estimated diagnosis dates of deaths and cured cases were obtained on the basis of the median death or medium cure time, respectively. Finally, the instant fatality rate of COVID-19 was calculated according to the numbers of deaths and cured cases on the same estimated diagnosis dates. ResultsFrom Jan 1, 2020 to Feb 22, 2020 in Wuhan City, the instant case fatality rate of COVID-19 was 3.4%[~]19.5% and the instant cured rate was 80.0%[~]96.6%. The average fatality rate reached 11.4% while the average cure rate was 88.6%. During the same period in Hubei Province, the instant case fatality rate was 3.8%[~]16.6% and the instant cured rate was 83.4%[~]96.6%. The average fatality rate and the average cure rate were 9.2% and 91.8%, respectively. ConclusionsThe fatality rate and cure rate of COVID-19 in Wuhan City and Hubei Province were underestimated. Wuhan showed higher fatality rate and cure rate than the whole Hubei Province did.

20.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20025999

RESUMO

The COVID-19 China coronavirus started in Dec 2019 was challenged by the lack of accurate serological diagnostic tool for this deadly disease to quickly identify and isolate the infected patients. The generation of COVID-19-specific antibodies is essential for such tasks. Here we report that polyclonal and monoclonal antibodies were generated by immunizing animals with synthetic peptides corresponding to different areas of Nucleoprotein (N) of COVID-19. The specificities of the COVID-19 antibodies were assessed by Western Blot analysis against NPs from COVID-19, MERS and SARS. Antibodies were used for immunohistochemistry staining of the tissue sections from COVID-19 infected patient, as a potential diagnostic tool. A Sandwich ELISA kit was quickly assembled for quantitation of the virus/NP of COVID-19 concentrations in the vaccine preparations. Development of POCT is also aggressively undergoing.

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