9 research outputs found
Surface-enhanced Raman spectroscopy study of 4-ATP on gold nanoparticles for basal cell carcinoma fingerprint detection
The surface-enhanced Raman signals of 4-aminothiophenol (4-ATP) attached to the surface of colloidal gold nanoparticles with size distribution of 2 to 5 nm were used as a labeling agent to detect basal cell carcinoma (BCC) of the skin. The enhanced Raman band at 1075 cm-1 corresponding to the C-S stretching vibration in 4-ATP was observed during attachment to the surface of the gold nanoparticles. The frequency and intensity of this band did not change when the colloids were conjugated with BerEP4 antibody, which specifically binds to BCC. We show the feasibility of imaging BCC by surface-enhanced Raman spectroscopy, scanning the 1075 cm-1 band to detect the distribution of 4ATP-coated gold nanoparticles attached to skin tissue ex vivo
Evolution of size and shape of gold nanoparticles during long-time aging
The evolution of size and shape of gold nanoparticles was studied during long-time aging. The initial
particle size of 2e5 nm increased to about 25 nm in one year of storage. It was revealed that the main
mechanism of particle growth is Ostwald ripening, however, fusion of particles was also observed.
Additionally, while the initial particles have spherical morphology, the grown particles show various
shapes such as sphere, bipyramid, decahedron, deca-tetrahedron, triangular plate and rod. Twin
boundaries with large frequency of w5% were detected inside the particles which have an important
effect on the evolution of morphology. This study suggests that aging may be a new way of tuning size
and shape of gold nanoparticles
Synthesis of ZnS:Mn–Fe3O4 bifunctional nanoparticles by inverse microemulsion method
ZnS:Mn–Fe3O4 bifunctional nanoparticles were synthesized by inverse microemulsion method for biomedicine applications. The bifunctional nanoparticles were combined from prepared ZnS:Mn and Fe3O4 nanoparticles in a SiO2 cover matrix. Results show that bifunctional nanoparticles, apart from exhibiting magnetism, have photoluminescence properties, which support the applications targeting biomedicine fluorescent diagnostics as well as magnetic cell sorting or drug delivery
Magnetic nanoparticles embedded in microlasers for controlled transport in different sensing media
In recent years, whispering gallery mode microlasers have attracted tremendous interest in sensing due to their ultra-high sensitivity at atomic levels. However, due to the non-magnetic properties, it is difficult to locate the microlasers at hard-to-reach positions, thus, limiting their sensing potential in many in-vitro and in-vivo applications. In this work, we report magnetic microlasers fabricated by encapsulating Ni0.2Zn0.8Fe2O4 magnetic nanoparticles (MNPs) within their cavity made of bovine serum albumin. The presence of MNPs allows the transportable actuation of the magnetic microlasers while maintaining lasing emission characteristics. Microlasers with various concentrations of MNPs are investigated to identify the optimum concentration that can balance a good magnetization, a low lasing threshold, and a high quality (Q) factor. These magnetic microlasers can be employed for sensing applications where sensors need to be navigated through different sensing media. As a proof of concept, we observed a clear shift of lasing wavelength of a magnetic microlaser while dragging it through different adjacent media by magnetic navigation. This result demonstrates the potential applications of magnetic microlasers for future biological and chemical applications.11Nsciescopu
Factors related to intracerebral haematoma in patients with aneurysmal subarachnoid haemorrhage in Vietnam: a multicentre prospective cohort study
Objectives To investigate the impact of intracerebral haematoma (ICH) on the outcomes and the factors related to an ICH in patients with aneurysmal subarachnoid haemorrhage (aSAH) in a low- and middle-income country.Design A multicentre prospective cohort study.Setting Three central hospitals in Hanoi, Vietnam.Participants This study included all patients (≥18 years) presenting with aSAH to the three central hospitals within 4 days of ictus, from August 2019 to June 2021, and excluded patients for whom the admission Glasgow Coma Scale was unable to be scored or patients who became lost at 90 days of follow-up during the study.Outcome measures The primary outcome was ICH after aneurysm rupture, defined as ICH detected on an admission head CT scan. The secondary outcomes were 90-day poor outcomes and 90-day death.Results Of 415 patients, 217 (52.3%) were females, and the median age was 57.0 years (IQR: 48.0–67.0). ICH was present in 20.5% (85/415) of patients with aSAH. There was a significant difference in the 90-day poor outcomes (43.5% (37/85) and 29.1% (96/330); p=0.011) and 90-day mortality (36.5% (31/85) and 20.0% (66/330); p=0.001) between patients who had ICH and patients who did not have ICH. The multivariable regression analysis showed that systolic blood pressure (SBP) ≥140 mm Hg (adjusted odds ratio (AOR): 2.674; 95% CI: 1.372 to 5.214; p=0.004), World Federation of Neurosurgical Societies (WFNS) grades II (AOR: 3.683; 95% CI: 1.250 to 10.858; p=0.018) to V (AOR: 6.912; 95% CI: 2.553 to 18.709; p<0.001) and a ruptured middle cerebral artery (MCA) aneurysm (AOR: 3.717; 95% CI: 1.848 to 7.477; p<0.001) were independently associated with ICH on admission.Conclusions In this study, ICH was present in a substantial proportion of patients with aSAH and contributed significantly to a high rate of poor outcomes and death. Higher SBP, worse WFNS grades and ruptured MCA aneurysms were independently associated with ICH on admission
Validation of the accuracy of the modified World Federation of Neurosurgical Societies subarachnoid hemorrhage grading scale for predicting the outcomes of patients with aneurysmal subarachnoid hemorrhage.
BackgroundEvaluating the prognosis of patients with aneurysmal subarachnoid hemorrhage (aSAH) who may be at risk of poor outcomes using grading systems is one way to make a better decision on treatment for these patients. This study aimed to compare the accuracy of the modified World Federation of Neurosurgical Societies (WFNS), WFNS, and Hunt and Hess (H&H) Grading Scales in predicting the outcomes of patients with aSAH.MethodsFrom August 2019 to June 2021, we conducted a multicenter prospective cohort study on adult patients with aSAH in three central hospitals in Hanoi, Vietnam. The primary outcome was the 90-day poor outcome, measured by a score of 4 (moderately severe disability) to 6 (death) on the modified Rankin Scale (mRS). We calculated the areas under the receiver operator characteristic (ROC) curve (AUROCs) to determine how well the grading scales could predict patient prognosis upon admission. We also used ROC curve analysis to find the best cut-off value for each scale. We compared AUROCs using Z-statistics and compared 90-day mean mRS scores among intergrades using the pairwise multiple-comparison test. Finally, we used logistic regression to identify factors associated with the 90-day poor outcome.ResultsOf 415 patients, 32% had a 90-day poor outcome. The modified WFNS (AUROC: 0.839 [95% confidence interval, CI: 0.795-0.883]; cut-off value≥2.50; PAUROCConclusionsIn this study, the modified WFNS, WFNS, and H&H scales all had good discriminatory abilities for the prognosis of patients with aSAH. Because of the better effect size in predicting poor outcomes, the modified WFNS scale seems preferable to the WFNS and H&H scales