Dextran mediated MnFe2O4/ZnS opto-magnetic nanocomposites with different concentrations of ZnS were competently synthesized adopting the co-precipitation method. The structural, morphological, ...magnetic, and optical properties of the nanocomposites were exhaustively characterized by XRD, HRTEM, FTIR, VSM techniques, and PL spectroscopy. XRD spectra demonstrate the existence of the cubic spinel phase of MnFe2O4 and the cubic zinc blend phase of ZnS in the nanocomposites. HRTEM images show the average crystallite size ranges of 15–21 nm for MnFe2O4 and 14–45 nm for ZnS. Investigation of the FTIR spectra reveals the incorporation of ZnS nanoparticles on the surface of MnFe2O4 nanoparticles by dint of biocompatible surfactant dextran. The nanocomposites exhibit both magnetic and photoluminescence properties. Photoluminescence analysis confirmed the redshift of the emission peaks owing to the trap states in the ZnS nanocrystals. The room temperature VSM analysis shows that the saturation magnetization and coercivity of MnFe2O4 nanoparticles initially increase then decrease with the increasing concentration of ZnS in the nanocomposite. The induction heating analysis shows that the presence of dextran enhances the self heating properties of the MnFe2O4/ZnS nanocomposites which can also be controlled by tailoring the concentration of the ZnS nanoparticles. These suggest that MnFe2O4/Dex/ZnS is a decent candidate for hyperthermia applications.
Exchange bias (EB) of magnetic nanoparticles (MNPs) in the nanoscale regime has been extensively studied by researchers, which have opened up a novel approach in tuning the magnetic anisotropy ...properties of magnetic nanoparticles (MNPs) in prospective application of biomedical research such as magnetic hyperthermia. In this work, we report a comparative study on the effect of magnetic EB of normal and inverted core@shell (CS) nanostructures and its influence on the heating efficiency by synthesizing Antiferromagnetic (AFM) NiO (N) and Ferrimagnetic (FiM) Fe
O
(F). The formation of CS structures for both systems is clearly authenticated by XRD and HRTEM analyses. The magnetic properties were extensively studied by Vibrating Sample Magnetometer (VSM). We reported that the inverted CS NiO@Fe
O
(NF) MNPs have shown a greater EB owing to higher uncompensated spins at the interface of the AFM, in comparison to the normal CS Fe
O
@NiO (FN) MNPs. Both the CS systems have shown higher SAR values in comparison to the single-phased F owing to the EB coupling at the interface. However, the higher surface anisotropy of F shell with more EB field for NF enhanced the SAR value as compared to FN system. The EB coupling is hindered at higher concentrations of NF MNPs because of the enhanced dipolar interactions (agglomeration of nanoparticles). Both the CS systems reach to the hyperthermia temperature within 10 min. The cyto-compatibility analysis resulted in the excellent cell viability (> 75%) for 3 days in the presence of the synthesized NPs upto 1 mg/ml. These observations endorsed the suitability of CS nanoassemblies for magnetic fluid hyperthermia applications.
MnFe2O4/ZnS magneto-fluorescent nanocomposite were synthesized by simple co-precipitation method and its structural, morphological, optical and magnetic characterization were done by XRD, HRTEM, FTIR ...and VSM techniques. The presence of MnFe2O4 and ZnS in the nanocomposites was confirmed by XRD. Magnetic study shows that the nanoparticles manifest near superparamagnetic behaviour with a small coercivity of ∼66 G at room temperature and saturation magnetization significantly increases after coating ZnS on the surface of MnFe2O4 core. The FTIR study confirms the incorporation of ZnS nanoparticles on the surface of MnFe2O4 nanoparticles. PL spectra demonstrated the red shifted emission of nanocomposites as compared with that of pure ZnS. The heating efficiency of the nanocomposites is measured by its SAR and ILP values. This study exhibits the quantitative link between the sizes and saturation magnetization which is intimately intertwined with the heating efficiency of the nanoparticles.
•Successfully synthesized MnFe2O4/ZnS Magnetic fluorescence nanocomposites.•The nanocomposites shows both magnetic and optical properties.•The nanocomposite shows high heating efficiency then ferrite nanoparticles for magnetic hyperthermia applications.
True penicillin allergy is rare and is commonly incorrectly reported. In fact, less than five percent of patients who report a penicillin allergy will have a currently active clinically-significant ...IgE- or T-cell-mediated hypersensitivity when appropriately tested. Penicillin is the agent of choice for intrapartum antibiotic prophylaxis to reduce the risk of group B streptococcus early-onset disease in the newborn. Inaccurate penicillin allergy status may lead to inappropriate antibiotic use, as most alternative drugs are more expensive and broader spectrum than penicillin. Penicillin allergy testing has been found to be safe in pregnancy and cost-effective in other patient populations.
To evaluate the cost-effectiveness of penicillin allergy testing and appropriate antibiotic treatment (test then treat strategy) compared to usual care among pregnant women.
We developed a decision tree to evaluate the cost of providing appropriate care via a test then treat strategy for pregnant women who report a penicillin allergy, compared to usual care.
Using the test then treat strategy the additional cost to ensure appropriate care for all pregnant women who report a penicillin allergy, was $1122.38 per person. Adopting a test then treat strategy increased the number of appropriate antibiotic use from 7,843/10,000 to 10,000/10,000 simulations.
Our results show that a test then treat strategy for pregnant women who report a penicillin allergy is a good-value intervention.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We investigate the efficacy of polyethylene glycol (PEG) and amine-functionalized MWCNT decorated with MnFe
2
O
4
nanocomposites as heating material for magnetic hyperthermia applications. Samples ...are prepared by a standard solvothermal method. Phase formation of MnFe
2
O
4
has been confirmed by X-ray diffractogram and attachment of nanoparticles on the surface of functionalized MWCNT is evident from transmission electron microscopic image of nanocomposite. Fourier transform infrared spectrum of PEG-functionalized MWCNT and amine-functionalized MWCNT confirmed the presence of PEG and amine group, respectively. As desirable for stability in magnetic hyperthermia, vibration sample magnetometer study suggests superparamagnetic behaviour of all the samples at temperatures 300 K, 200 K and 100 K except at 5 K, which is below blocking temperature as confirmed by ZFC–FC curves. Estimated Curie temperature (
T
C
) and room temperature effective anisotropy is found to increase in nanocomposites, highest for amine-functionalized MWCNT/MnFe
2
O
4
nanocomposite. A clear correlation between effective anisotropy and heat generation capability (SAR/ILP) has been observed: higher the anisotropy, higher is the heat generation capability (SAR/ILP).
Here we report the effect of surface functionalization on Fe3O4 assembled nanoclusters with biopolymers, like chitosan and dextran using the solvo-thermal route. XRD analyses confirmed the formation ...of cubic spinel structure with crystallite sizes ranging from 11 to 14 nm. HRTEM analyses revealed the formation of spherical nanoclusters. Magnetic measurements demonstrate the typical ferromagnetic behavior with saturation magnetization (Ms) up to 71.048, 69.829 and 68.228 Am2Kg−1 for Fe3O4 (FO), chitosan coated Fe3O4 (CFO) and dextran coated Fe3O4 (DFO) respectively at room temperature. Negligible coercivity (Hc) and remenance (Mr) at room temperature implies nearly superparamagnetic behavior. Field cooled (FC) and Zero field cooled (ZFC) measurements of magnetization at an applied field of 100 Oe resulting in the blocking temperature above room temperature for all the samples. Induction heating ability of the samples under alternating magnetic field were studied by means of specific absorption rate measurements (SAR). It is shown that the surface functionalization significantly enhanced the SAR value up to 40% i.e., from 144.08 W/g for FO to 233.28 W/g for DFO at 1 mg/ml concentration. The study also concluded that the dipolar interactions are solely responsible for self-heating behavior of the nanoparticles. It was observed that by changing the sample concentration and different coatings, the final temperature can be tuned to the intended therapeutic (hyperthermia) temperature range (40–44 °C). The in vitro cytocompatibility test resulted in cell viability of more than 90%, which proved that the prepared nanomaterials are promising for the hyperthermia applications.
•Spherical magnetite nanoclusters were synthesized and functionalized with chitosan and dextran using the solvo-thermal route.•Negligible coercivity (Hc) and remenance (Mr) were observed at room temperature implying nearly superparamagetic behavior.•Enhanced SAR values were obtained for the functionalized samples, due to the reduced dipolar interactions.•The in vitro study resulted in more than 90 % cell viability, indicating the samples are ideal for hyperthermia applications.
Background Infants with hypoplastic left heart syndrome (HLHS) are susceptible to pre-Norwood comorbidities (PCs) and complications. This study aimed to describe the effect of PCs on timing and ...survival of Norwood palliation (NP). Methods A single-center, retrospective review of infants with HLHS who underwent initial NP between 2003 and 2010 was performed. PCs included intact atrial septum, ≥ moderate atrioventricular regurgitation (AVVR), no antenatal diagnosis, mitral stenosis/aortic atresia subtype, genetic abnormality, and prematurity. Complications included pre-NP mechanical ventilation, inotropic support, infection, arrhythmia, and end-organ injury. The primary outcome measure was survival after NP. Results 113 patients were included with 78 (69%) patients having at least one PC and 61 (78%) of those patients having at least one complication. Patients with PCs underwent NP later than those without PCs (7 vs 6 days, P = .036) as well as when associated with a complication (8 vs 5 days, P < .001). Patients with PCs had similar post-Norwood hospital length of stay ( P = .116) except when the PC occurred in conjunction with a complication (28 vs 21 days; P = .015). In-hospital mortality post-NP was 10% and interstage mortality was 15%. On multivariable analysis, ≥ moderate AVVR was associated with increased overall mortality (OR 2.8, 95% CI 1.3-6.2). Age at NP was not associated with mortality ( P = .638). Conclusions Although PCs are common in infants with HLHS, only ≥ moderate AVVR was associated with increased mortality in this single-center experience. Older age at NP was not a significant risk factor for interstage mortality.
•BiFeO3/Fe3O4 composite nanoparticles with varying concentration of Fe3O4 were prepared via the sol–gel technique.•The magnetic properties of the nanocomposites were found to vary with an increase in ...Fe3O4 content.•The ideal concentration of Fe3O4 in the nanocomposite for hyperthermia application was found to be 30%.•The optimized SAR values was found to be 168 w/g and was greatly influenced by the magnetic dipolar interaction.
The development of perovskite/spinel nanocomposite BiFeO3/Fe3O4 (BFO/FO) holds particular interest for applications in magnetic hyperthermia therapy (MHT). This work offers a significant avenue for advancing material properties and evaluating the heating efficiency, considering the impact of structure, and magnetic characteristics within the perovskite/spinel system. A sol–gel synthesis process for phase-pure BiFeO3 production was successful, which is subsequently utilized with Fe3O4 to form a nanocomposite (BiFeO3)1−x/(Fe3O4)x. Our findings indicate that increasing the concentration of Fe3O4 in the nanocomposite enhances the saturation magnetization and the specific absorption rate (SAR). Importantly, the addition of BiFeO3 to Fe3O4 further enhances the nanocomposite's heating efficiency. This study underscores the potential of perovskite/spinel nanocomposites in realizing advanced materials with tailored properties and multifaceted functionalities.
Abstract
A LabVIEW
TM
based VIRTUAL INSTRUMENT (VI)
system is designed with the aid of an Arduino-Uno microcontroller,
which is used as a data acquisition system for collecting data from
an AC ...magnetic susceptometer operating in the range of 10 Hz to
10 kHz. The magnetic susceptometer system was indigenously built
using standard modules/components and is capable of measuring AC
magnetic susceptibility from room temperature down to 100 K. The
proposed VI can have diverse applications and may be modified
according to the user requirements. Herein, we have decided to focus
its applicability on the automation of an AC susceptometer
integrated with an inexpensive signal processing unit comprising an
AD630-based lock-in-amplifier and an ICL8038-based signal
generator. Data from the lock-in- amplifier, the signal generator,
and the temperature sensor are interfaced to a computer via an
Arduino-Uno microcontroller. A program (VI) developed using LabVIEW
is used to acquire and record in a PC the data from the AC magnetic
susceptometer.
Pleural and pericardial involvements are well recognized in eosinophilic granulomatosis with polyangiitis (EGPA) but considered rare manifestations of the other forms of antineutrophil cytoplasmic ...autoantibody (ANCA)-associated vasculitis (AAV).
What are the frequency and clinical characteristics of pleuritis and pericarditis in AAV?
and Methods: Using an institutional database of 1,830 patients with AAV, we analyzed clinical notes and diagnosis codes for key words related to pleuritis and pericarditis. Chart review to confirm these findings was performed.
Eighty-eight of 1,058 patients (8.3%) with granulomatosis with polyangiitis (GPA), 27 of 267 (10.1%) with microscopic polyangiitis (MPA), and 35 of 201 (17.4%) with EGPA had a manifestation of pleuritis and/or pericarditis attributable to vasculitis. There was a higher frequency of pericarditis in EGPA compared with that in the other AAVs (P < .01). There was no difference in the frequency of pleuritis in GPA, MPA, or EGPA. In the 156 patients with AAV with pleuritis and/or pericarditis, this was a presenting feature in 127 (81.4%). Overall, it was a presenting feature in 6.9% of all patients with AAV, including 6.5% with GPA, 8.6% with MPA, and 15.9% with EGPA.
Pleuritis and pericarditis occur across all the AAVs and, when present, are commonly presenting features of these diseases. Patients with EGPA have a higher proportion of pericardial involvement compared with pleural involvement, whereas this distribution is more equal in patients with GPA and MPA. Pleuritis and pericarditis are underrecognized features of AAV. All forms of AAV should be considered in the differential diagnosis when evaluating a patient with pleuritis or pericarditis.
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