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1.
BMC Infect Dis ; 24(1): 573, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38853273

RESUMO

PURPOSE: Frailty is a vulnerable state to stressors due to the loss of physiological reserve as a result of multisystem dysfunction. The physiological and laboratory-based frailty index (FI-Lab), depending on laboratory values and vital signs, is a powerful tool to capture frailty status. The aim of this study was to assess the relationship between FI-Lab and in-hospital mortality in patients with septic shock. METHODS: Baseline data for patients with sepsis in the intensive care unit were retrieved from the Critical Care Medicine Database (MIMIC-IV, v2.2). The primary outcome was mortality during hospitalization. The propensity score matching (PSM) method was used to analyze the basic conditions during hospitalization between groups.The FI-Lab was analysed for its relationship with in-hospital mortality using logistic regression according to continuous and categorical variables, respectively, and described using the restricted cubic spline (RCS). Survival was compared between groups using Kaplan-Meier (KM) curves. Subgroup analyses were used to improve the stability of the results. RESULTS: A total of 9219 patients were included. A cohort score of 1803 matched patients was generated after PSM. The analyses showed that non-surviving patients with septic shock in the ICU had a high FI-Lab index (P<0.001). FI-Lab, whether used as a continuous or categorical variable, increased with increasing FI-Lab and increased in-hospital mortality (P<0.001).Subgroup analyses showed similar results. RCS depicts this non-linear relationship. KM analysis shows the cumulative survival time during hospitalisation was significantly lower as FI-Lab increased (log-rank test, P<0.001). CONCLUSION: Elevated FI-Lab is associated with increased in-hospital mortality in patients with septic shock.


Assuntos
Cuidados Críticos , Fragilidade , Mortalidade Hospitalar , Unidades de Terapia Intensiva , Choque Séptico , Sinais Vitais , Humanos , Choque Séptico/mortalidade , Feminino , Masculino , Idoso , Fragilidade/mortalidade , Estudos Retrospectivos , Pessoa de Meia-Idade , Unidades de Terapia Intensiva/estatística & dados numéricos , Bases de Dados Factuais , Idoso de 80 Anos ou mais
2.
Lipids Health Dis ; 23(1): 110, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627726

RESUMO

BACKGROUND: There is evidence for an association between the gut microbiome and endometriosis. However, their causal relationship and the mediating role of lipid metabolism remain unclear. METHODS: Using genome-wide association study (GWAS) data, we conducted a bidirectional Mendelian randomization (MR) analysis to investigate the causal relationships between gut microbiome and endometriosis. The inverse variance weighted (IVW) method was used as the primary model, with other MR models used for comparison. Sensitivity analysis based on different statistical assumptions was used to evaluate whether the results were robust. A two-step MR analysis was further conducted to explore the mediating effects of lipids, by integrating univariable MR and the multivariate MR method based on the Bayesian model averaging method (MR-BMA). RESULTS: We identified four possible intestinal bacteria genera associated with the risk of endometriosis through the IVW method, including Eubacterium ruminantium group (odds ratio [OR] = 0.881, 95% CI: 0.795-0.976, P = 0.015), Anaerotruncus (OR = 1.252, 95% CI: 1.028-1.525, P = 0.025), Olsenella (OR = 1.110, 95% CI: 1.007-1.223, P = 0.036), and Oscillospira (OR = 1.215, 95% CI: 1.014-1.456, P = 0.035). The further two-step MR analysis identified that the effect of Olsenella on endometriosis was mediated by triglycerides (proportion mediated: 3.3%; 95% CI = 1.5-5.1%). CONCLUSION: This MR study found evidence for specific gut microbiomes associated with the risk of endometriosis, which might partially be mediated by triglycerides.


Assuntos
Endometriose , Microbioma Gastrointestinal , Feminino , Humanos , Microbioma Gastrointestinal/genética , Endometriose/genética , Teorema de Bayes , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Lipídeos , Triglicerídeos
3.
BMC Womens Health ; 22(1): 551, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36575516

RESUMO

BACKGROUND: True hermaphroditism is a rare condition. It is defined as the presence of both testicular and ovarian tissues in the same individual. Sex cord tumour with annular tubules (SCTAT) is a rare stromal tumour of the sex cord that occurs mostly in the ovaries. CASE PRESENTATION: A 16-year-old girl presented to the gynaecology department with primary amenorrhea. Gynaecological examination revealed an enlarged clitoris that looked like a small penis. The chromosome karyotype was chimaera. The postoperative pathology confirmed true hermaphroditism with SCTAT. The patient underwent hormonal replacement after an operation and had no evidence of recurrence for 6 months. CONCLUSION: Cases of true hermaphroditism with SCTAT are extremely rare conditions. Surgery and hormonal replacement are important for improving the prognosis of such patients.


Assuntos
Neoplasias Ovarianas , Transtornos Ovotesticulares do Desenvolvimento Sexual , Tumores do Estroma Gonadal e dos Cordões Sexuais , Masculino , Feminino , Humanos , Adolescente , Neoplasias Ovarianas/complicações , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/cirurgia , Transtornos Ovotesticulares do Desenvolvimento Sexual/complicações , Transtornos Ovotesticulares do Desenvolvimento Sexual/diagnóstico , Transtornos Ovotesticulares do Desenvolvimento Sexual/cirurgia , Tumores do Estroma Gonadal e dos Cordões Sexuais/complicações , Tumores do Estroma Gonadal e dos Cordões Sexuais/diagnóstico , Tumores do Estroma Gonadal e dos Cordões Sexuais/cirurgia , Prognóstico
4.
J Minim Invasive Gynecol ; 27(3): 704-711, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31255787

RESUMO

STUDY OBJECTIVE: To evaluate high-intensity focused ultrasound (HIFU) ablation therapy for abdominal wall endometriosis (AWE). DESIGN: A retrospective study. SETTING: Gynecologic department of a teaching hospital in China. PATIENTS: Thirty patients with AWE were treated from May 2013 to December 2015. INTERVENTIONS: Thirteen patients were treated with HIFU ablation and 17 patients with surgical resection. MEASUREMENTS AND MAIN RESULTS: Color Doppler ultrasonography and magnetic resonance imaging were used to observe the lesions before and after treatment. In addition, recovery time, complications, and adverse reactions of the 2 groups were compared. Menstrual pain was relieved after treatment in all 30 patients. After treatment, the lesions in patients who underwent HIFU ablation decreased gradually, and there was no recurrence. Symptoms recurred in 1 patient in the surgery group 12 months after surgery. The post-treatment hospital length of stay of the HIFU ablation group (1.00 ± 0 days) was significantly shorter than that of the surgical group (5.23 ± 1.24 days; p <.001). The incidence of fever (0% vs 11.8%; p = .049) and complications of the urinary system (7.7% vs 17.6%; p = .043) in the HIFU ablation group were significantly lower than that of the surgical group. CONCLUSIONS: HIFU ablation therapy is a promising treatment for AWE, and further study is warranted.


Assuntos
Parede Abdominal/cirurgia , Endometriose/cirurgia , Ablação por Ultrassom Focalizado de Alta Intensidade , Doenças Peritoneais/cirurgia , Parede Abdominal/patologia , Adulto , China , Dismenorreia/diagnóstico , Dismenorreia/etiologia , Dismenorreia/cirurgia , Endometriose/diagnóstico , Endometriose/patologia , Feminino , Procedimentos Cirúrgicos em Ginecologia/efeitos adversos , Procedimentos Cirúrgicos em Ginecologia/métodos , Ablação por Ultrassom Focalizado de Alta Intensidade/efeitos adversos , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Humanos , Tempo de Internação , Imageamento por Ressonância Magnética , Doenças Peritoneais/diagnóstico , Doenças Peritoneais/patologia , Recidiva , Estudos Retrospectivos , Resultado do Tratamento , Ultrassonografia Doppler em Cores
5.
Sensors (Basel) ; 20(4)2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32075012

RESUMO

In order to improve the performance of surface plasmon resonance (SPR) biosensor, the structure based on two-dimensional (2D) of graphene and transition metal dichalcogenides (TMDCs) are proposed to greatly enhance the Goos-Hänchen (GH) shift. It is theoretically proved that GH shift can be significantly enhanced in SPR structure coated with gold (Au)-indium tin oxide (ITO)-TMDCs-graphene heterostructure. In order to realize high GH shifts, the number of TMDCs and graphene layer are optimized. The highest GH shift (-801.7 λ) is obtained by Au-ITO-MoSe2-graphene hybrid structure with MoSe2 monolayer and graphene bilayer, respectively. By analyzing the GH variation, the index sensitivity of such configuration can reach as high as 8.02 × 105 λ/RIU, which is 293.24 times of the Au-ITO structure and 177.43 times of the Au-ITO-graphene structure. The proposed SPR biosensor can be widely used in the precision metrology and optical sensing.

6.
Sensors (Basel) ; 18(2)2018 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-29443871

RESUMO

Coalbed methane (CBM) is one kind of clean-burning gas and has been valued as a new form of energy that will be used widely in the near future. When producing CBM, the working level within a CBM wellbore annulus needs to be monitored to dynamically adjust the gas drainage and extraction processes. However, the existing method of measuring the working level does not meet the needs of accurate adjustment, so we designed a new sensor for this purpose. The principle of our sensor is a liquid pressure formula, i.e., the sensor monitors the two-phase flow patterns and obtains the mean density of the two-phase flow according to the pattern recognition result in the first step, and then combines the pressure data of the working level to calculate the working level using the liquid pressure formula. The sensor was tested in both the lab and on site, and the tests showed that the sensor's error was ±8% and that the sensor could function well in practical conditions and remain stable in the long term.

7.
Am J Cancer Res ; 13(9): 4179-4191, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37818080

RESUMO

Ovarian cancer is one of the most lethal and drug-resistant gynecological diseases. Among the various post-transcriptional RNA modifications, N6-methyladenosine (m6A) has been implicated in several malignancies, including breast cancer. Recently, the biological significance of long noncoding RNA (lncRNA) methylation has garnered significant attention. The N6-methyladenosine (m6A) demethylase ALKBH5 (Alkylation Repair Homolog Protein 5) has been shown to promote ovarian cancer development by reducing the methylation of the lncRNA RMRP. In this study, we found that a hypoxic microenvironment induces an increase in ALKBH5 expression in ovarian cancer. Both in vitro and in vivo investigations demonstrated that ALKBH5, which is overexpressed in human ovarian cancer, promotes carcinogenesis. Furthermore, using bioinformatics analysis, we predicted interactions between ALKBH5 and lncRNAs, confirming RMRP as a potential binding lncRNA for ALKBH5. ALKBH5 was found to upregulate RMRP expression via demethylation. Knockdown of RMRP in ovarian cancer cell lines led to a decrease in cell growth and migration. Additionally, we demonstrated that the inhibition of ovarian cancer by ALKBH5 knockdown is partially mediated by RMRP suppression. In conclusion, our findings reveal a novel mechanism in which ALKBH5 promotes ovarian cancer by demethylating the lncRNA RMRP, suggesting its potential as a therapeutic target for the disease.

8.
Nanomaterials (Basel) ; 13(10)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37242071

RESUMO

Mixed-halide perovskite quantum dots (PeQDs) are the most competitive candidates in designing solar cells and light-emitting devices (LEDs) due to their tunable bandgap and high-efficiency quantum yield. However, phase separation in mixed-halide perovskites under illumination can form rich iodine and bromine regions, which change its optical responses. Herein, we synthesize PeQDs combined with mesoporous zinc-based metal organic framework (MOF) crystals, which can greatly improve the stability of anti-anion exchange, including photo-, thermal, and long-term stabilities under illumination. This unique structure provides a solution for improving the performance of perovskite optoelectronic devices and stabilizing mixed-halide perovskite devices.

9.
Nanoscale ; 15(13): 6234-6242, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36892211

RESUMO

Spacer organic cations in two-dimensional (2D) perovskites play vital roles in inducing structural distortion of the inorganic components and dominating unique excitonic properties. However, there is still little understanding of spacer organic cations with identical chemical formulas, and different configurations have an impact on the excitonic dynamics. Herein, we investigate and compare the evolution of the structural and photoluminescence (PL) properties of [CH3(CH2)4NH3]2PbI4 ((PA)2PbI4) and [(CH3)2CH(CH2)2NH3]2PbI4 ((PNA)2PbI4) with isomeric organic molecules for spacer cations by combining steady-state absorption, PL, Raman and time-resolved PL spectra under high pressures. Intriguingly, the band gap is continuously tuned under pressure and decreased to 1.6 eV at 12.5 GPa for (PA)2PbI4 2D perovskites. Simultaneously, multiple phase transitions occur and the carrier lifetimes are prolonged. In contrast, the PL intensity of (PNA)2PbI4 2D perovskites exhibits an almost 15-fold enhancement at 1.3 GPa and an ultrabroad spectral range of up to 300 nm in the visible region at 7.48 GPa. These results indicate that the isomeric organic cations (PA+ and PNA+) with different configurations significantly mediate distinct excitonic behaviors due to different resilience to high pressures and reveal a novel interaction mechanism between organic spacer cations and inorganic layers under compression. Our findings not only shed light on the vital roles of isomeric organic molecules as organic spacer cations in 2D perovskites under pressure, but also open a route to rationally design highly efficient 2D perovskites incorporating such spacer organic molecules in optoelectronic devices.

10.
Opt Lett ; 37(16): 3438-40, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23381283

RESUMO

We present spectroscopic diffraction phase microscopy (sDPM) as a method capable of measuring quantitative phase images at multiple wavelengths. sDPM uses a spatial light modulator at the Fourier plane of a lens to select desired wavelengths from the white light illumination of a grating. The quantitative phase information at different wavelengths allows us to decouple the refractive index and the thickness from the phase shift induced by biological cells. We demonstrate the capability of the setup by dispersion measurements of microsphere beads and RBCs.


Assuntos
Algoritmos , Aumento da Imagem/instrumentação , Microscopia de Contraste de Fase/instrumentação , Microscopia de Contraste de Fase/métodos , Refratometria/instrumentação , Análise Espectral/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
11.
J Coll Physicians Surg Pak ; 32(12): 1576-1580, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36474378

RESUMO

OBJECTIVE: To detect methyltransferase-like (METTL) 16 expression in epithelial ovarian cancer (EOC) by immunohistochemistry (IHC), and its relationship with clinicohistopathological parameters and prognosis. STUDY DESIGN: Observational study. PLACE AND DURATION OF STUDY: Department of Gynaecology and Pathology, The First Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), from February to June 2022. METHODOLOGY: METTL16 expression in 115 EOC patients was evaluated by IHC. According to the immunoreactive score (IRS), scores <6 represented low expressions and ≥6 high expressions. Clinicopathologic data and follow-up information were collected for statistical evaluation. RESULTS: METTL16 expression decreased in EOC (p = 0.001) and affected the poor prognosis of EOC patients. Low METTL16 patients expression had significantly higher frequencies of advanced FIGO stage, low grade, more lymph node metastasis, high CA125 levels, bilateral disease, distant metastasis, and high frequency of neural/vascular invasion compared to high METTL16 patients (p ≤0.001, <0.001, <0.001, 0.017, 0.027, <0.001, and 0.010, respectively). The survival analysis showed that the overall survival (p <0.0001) as well as the disease-free survival (p <0.0001) were remarkably shorter in low METTL16 patients compared to high METTL16 patients, suggesting worse survival. CONCLUSION: There was a clear association between the expression of METTL16, poor prognostic factors, and lower survival of EOC patients, suggesting that it might exert a vital effect on the malignant progression / prognosis of EOC. KEY WORDS: Epithelial ovarian cancer (EOC), METTL16, Immunohistochemistry, Prognosis.


Assuntos
Metiltransferases , Neoplasias Ovarianas , Feminino , Humanos , Carcinoma Epitelial do Ovário , Relevância Clínica , Universidades
12.
J Immunol Res ; 2022: 6130806, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35733918

RESUMO

N6-methyladenosine (m6A) RNA methylation has been determined to execute crucial functions in tumorigenesis and cancer development. WT1-associated protein (WTAP) has an important "writer" role in m6A modification, and it is also a nuclear protein that colocalizes with splicing factors and plays a critical role in cell function and cancer progression. However, little is known about the role of WTAP in ovarian cancer (OC) and its mechanisms. In this study, we found for the first time that hypoxia-inducible factor (HIF)-1α could positively regulate increased expression of WTAP under hypoxia. And further results revealed that WTAP expression was closely associated with the clinicopathological features of OC, and high expression of WTAP predicted low survival rate in patients with OC. In addition, cell proliferation and invasive capacity were significantly reduced after knockdown of WTAP expression in OC cells. However, cell proliferation and invasive ability were significantly enhanced after overexpression of WTAP. Additionally, we find that WTAP interacts with DGCR8 (a crucial chip protein) to regulate the expression of microRNA-200 (miR-200) in an m6A-dependent way. Further experiments showed that the key glycolysis enzyme HK2 could be positively regulated by miR-200, which significantly affected the intracellular Warburg effect. In conclusion, this is considered uncovered that upregulation of WTAP expression by HIF-1α intercedes with miRNA processing, accelerates the Warburg impact, and advances the event and advancement of tumor, thus giving a novel viewpoint on m6A adjustment in OC movement.


Assuntos
MicroRNAs , Neoplasias Ovarianas , Fatores de Processamento de RNA , Adenosina/análogos & derivados , Proteínas de Ciclo Celular/genética , Feminino , Humanos , Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , MicroRNAs/genética , Neoplasias Ovarianas/genética , Fatores de Processamento de RNA/genética , Proteínas de Ligação a RNA/genética
13.
Front Surg ; 9: 813711, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35402502

RESUMO

Objective: To investigate the feasibility and short-term efficacy of gasless single-port laparoscopic inguinal lymphadenectomy through vulva incision (VEIL-V). Methods: The data of 9 patients diagnosed as vulvar squamous cell carcinoma who underwent single-port laparoscopic inguinal lymph node dissection through vulvectomy incision were retrospectively analyzed. And 13 patients who underwent laparoscopic inguinal lymph node dissection through lower abdominal subcutaneous approach as the control group (VEIL-H). The operation time, blood loss, numbers of unilateral lymph nodes, hospitalization time, and complications between the two groups were compared. Results: The operation time of VEIL-V was 56.11 ± 5.94 min, which were shorter than that of VEIL-H (74.62 ± 5.50 min; P = 0.013). Bleeding amount in the VEIL-H was 29.44 ± 2.56, which was significantly lower than that of the VEIL-H group (43.08 ± 4.14 ml; P = 0.021). In the two groups, the numbers of unilateral lymph nodes harvested were similar. The differences in the postoperative hospital stay, skin, and lymphatic complications were not statistically significant. Conclusion: Compared with VEIL-H, gasless single-port laparoscopic inguinal lymphadenectomy through vulva incision reduces the difficulty of operation with shorter operation time, and less blood loss, which can be a safe and mini-invasive surgical approach.

14.
IEEE Trans Cybern ; 52(5): 2896-2906, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33095726

RESUMO

In this article, the consensus of networked underactuated robotic systems subject to fixed and switched communication networks is discussed by developing some novel event-triggered control algorithms, which can synchronously guarantee the convergence of the active states, the boundedness of the velocities of passive actuators, and the exclusion of Zeno behaviors. In the cases of fixed networks, the sufficient criteria are established for the presented distributed event-triggered mechanisms with and without using neighbors' velocities, in order to achieve a better tradeoff between the communication load and system performance. Besides, in the situation of switched networks, the sufficient criterion is established by assuming that the union of the network has a spanning tree. A distributed sampled-data rule is constructed to decide when to update its own and neighbors' estimated positions, and thus further reduces the unnecessary control cost. Finally, by further extending the main results to three other sampled-data control algorithms, several examples with performance comparisons are provided to validate the efficiency and advantages of the theoretical results.

15.
Front Surg ; 9: 911553, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35923438

RESUMO

Objective: This study aims to investigate the feasibility and short-term efficacy of single-port laparoscopic-assisted transvaginal natural cavity endoscopic sacrospinous ligament suspensions (SvNOTES). Methods: A total of 30 patients diagnosed with anterior or/and middle pelvic organ prolapse Stages III and IV underwent natural vaginal cavity (SvNOTES), and 30 patients who underwent conventional sacrospinous ligament (SSLF) were used as a control group. The operation time, blood loss, postoperative POP-Q score, length of hospital stay, and complications were compared between the two groups. Results: The operation time for SvNOTE was (60 ± 13) min, which was longer than (30 ± 15) min for SSLF (P = 0.04). However, the bleeding amount in SvNOTE was 29.44 ± 2.56, significantly lower than that in the SSLF group (80 ± 10; P = 0.02), and the postoperative hospital stay in the SvNOTE group was (4 ± 2) days, longer than (3 ± 1) days in SSLF (P = 0.02). However, there were no intraoperative complications in the SvNOTE group, whereas one ureteral injury occurred in the SSLF group; in addition, the postoperative POP-Q score was significantly better in the SvNOTE group than that in the SSLF group with increasing time (P < 0.001). Conclusion: Compared with SSLF, single-port laparoscopic sacrospinous ligament suspension via the natural vaginal cavity is visualized, greatly improving the success rate of sacrospinous ligament fixation, with less blood loss and fewer complications, arguably a safer and minimally invasive surgical approach.

16.
Front Surg ; 9: 1010027, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36406350

RESUMO

Objective: To describe the surgical techniques and short-term outcomes for 50 cases of modified sacrospinous ligament fixation via the anterior vaginal wall path for pelvic organ prolapse. Methods: 100 patients with pelvic organ prolapse (stage III or stage IV based on POP-Q staging) from January 2018 to January 2020 were retrospectively analyzed. Among them, 50 patients received modified sacrospinous ligament fixation via the anterior vaginal wall path for pelvic organ prolapse (mSSLF group), while the other 50 patients received pelvic reconstruction using T4 mesh (T4 group). Operative time, blood loss, postoperative POP-Q score, length of the hospital stay, complications, and postoperative pain were compared between the two groups. Results: The duration of the operation in mSSLF group was (50 ± 15.2 min), which was shorter than that of the T4 group (60 ± 14.8 min) (p = 0.02). No intraoperative complications were reported from the mSSLF group, whereas one vascular injury occurred in the T4 group. In both groups, postoperative pain and painful intercourse was significantly lower in the mSSLF group than in the SSLF group (p < 0.001). The exposed mesh rate was lower than T4 group. Conclusions: The rates of intraoperative complications, postoperative pain and mesh erosion were significantly lower than those of the T4 group, but there was no significant difference in the efficacy and safety of the treatment of pelvic organ prolapse. So mSSLF may be a feasible technique to manage severe prolapse, with promising short-term efficacy and safety.

17.
Opt Express ; 19(2): 1016-26, 2011 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-21263640

RESUMO

We present spatial light interference microscopy (SLIM) as a new optical microscopy technique, capable of measuring nanoscale structures and dynamics in live cells via interferometry. SLIM combines two classic ideas in light imaging: Zernike's phase contrast microscopy, which renders high contrast intensity images of transparent specimens, and Gabor's holography, where the phase information from the object is recorded. Thus, SLIM reveals the intrinsic contrast of cell structures and, in addition, renders quantitative optical path-length maps across the sample. The resulting topographic accuracy is comparable to that of atomic force microscopy, while the acquisition speed is 1,000 times higher. We illustrate the novel insight into cell dynamics via SLIM by experiments on primary cell cultures from the rat brain. SLIM is implemented as an add-on module to an existing phase contrast microscope, which may prove instrumental in impacting the light microscopy field at a large scale.


Assuntos
Holografia/instrumentação , Holografia/métodos , Aumento da Imagem/instrumentação , Iluminação/instrumentação , Microscopia de Interferência/instrumentação , Neurônios/citologia , Animais , Células Cultivadas , Desenho de Equipamento , Análise de Falha de Equipamento , Microscopia de Interferência/métodos , Ratos
18.
Opt Lett ; 36(7): 1215-7, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21479034

RESUMO

We derive two mathematical relations between quantitative phase images of thin slices of inhomogeneous media and the scattering parameters of the bulk, i.e., scattering mean free path, l(s), and anisotropy factor, g. The l(s) turns out to be inversely proportional to the spatial variance of the phase shift, and g is related to the variance of the phase gradient. These formulas, referred collectively to as the scattering-phase theorem, allow for extracting l(s) and g in a spatially resolved manner and across an entire tissue section, that is, mapping large cross sections of tissues in terms of l(s) and g.


Assuntos
Modelos Teóricos , Espalhamento de Radiação , Luz
19.
Opt Lett ; 36(12): 2281-3, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21685993

RESUMO

We employed the scattering-phase theorem recently derived in our laboratory to extract tissue scattering properties from quantitative phase images. Using tissue path-length maps that contain nanoscale information about the tissue, the scattering mean free path l(s) and anisotropy factor g were measured in a spatially resolved manner.


Assuntos
Luz , Imagem Molecular/métodos , Espalhamento de Radiação , Animais , Anisotropia , Fígado/citologia , Miocárdio/citologia , Ratos
20.
RSC Adv ; 11(48): 30465-30471, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-35480288

RESUMO

CsPbBr3 nanocrystals (NCs) encapsulated by Cs4PbBr6 has attracted extensive attention due to good stability and high photoluminescence (PL) emission efficiency. However, the origin of photoluminescence (PL) emission from CsPbBr3/Cs4PbBr6 composite materials has been controversial. In this work, we prepare CsPbBr3/Cs4PbBr6 core/shell nanoparticles and firstly study the mechanism of its photoluminescence (PL) at the single-particle level. Based on photoluminescence (PL) intensity trajectories and photon antibunching measurements, we have found that photoluminescence (PL) intensity trajectories of individual CsPbBr3/Cs4PbBr6 core/shell NCs vary from the uniform longer periods to multiple-step intensity behaviors with increasing excitation level. Meanwhile, second-order photon correlation functions exhibit single photon emission behaviors especially at lower excitation levels. However, the PL intensity trajectories of individual Cs4PbBr6 NCs demonstrate apparent "burst-like" behaviors with very high values of g 2(0) at any excitation power. Therefore, the distinguishable emission statistics help us to elucidate whether the photoluminescence (PL) emission of CsPbBr3/Cs4PbBr6 core/shell NCs stems from band-edge exciton recombination of CsPbBr3 NCs or intrinsic Br vacancy states of Cs4PbBr6 NCs. These findings provide key information about the origin of emission in CsPbBr3/Cs4PbBr6 core/shell nanoparticles, which improves their utilization in the further optoelectronic applications.

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