4 research outputs found
Sodium yttrium fluoride based upconversion nano phosphors for biosensing
In the present study, NaYF4-Yb3+/Er3+ having the composition NaYF4-18%Yb3+/2%Er3+ and NaYF4-20%Yb3+/2%Er3+ with and without the addition of PVP (polyvinyl pyrolidone) have been synthesised by a solution method using NaF, yttrium nitrate, ytterbium nitrate and erbium nitrate as precursors. Upconversion spectra of prepared nanomaterial under 980 nm laser excitation have been studied. The variation in upconversion spectra with new born calf serum and myoglobin has been studied. Myoglobin (Mb) may be helpful when used in conjunction with other cardiac markers for rapid determination of acute myocardial ischemia, especially in patients with a typical chest pain or nonspecific ECG changes. The variation of UC fluorescence with addition of Mb indicates the suitability of using NaYF4 based UC nanoparticles in cardiac marker detection. The detailed study is currently under progress
Occurrence of vancomycin-resistant Staphylococcus aureus in the oral cavity of patients with dental caries
Oral streptococci are the major group of microbes isolated from oral microflora. They represent frequent pathogens of infective endocarditis (IE), and it is assumed that in most of the cases oral streptococci are acquired via mucosa layer of oral cavity. Staphylococcus aureus is also frequently isolated from IE as it accounts for 20%–30% of all cases. Vancomycin has been the most reliable therapeutic agent against infections caused by methicillin-resistant S. aureus (MRSA). The main objective of this study was to examine the occurrence of S. aureus species in dental caries specimens. Antimicrobial susceptibility testing of S. aureus to four antibiotics namely vancomycin, linezolid, teicoplanin, and daptomycin was performed. Detection of vancomycin resistance was conducted using polymerase chain reaction. Among the tested 150 strains, 98 were MRSA and of that 54 were vancomycin sensitive and 27 were resistant. All 98 MRSA strains were positive for mecA and 36 yielded pvl, whereas 13 carried vanA and only 2 were positive for vanB. Majority of the isolates showed sensitivity toward daptomycin and linezolid. Strains of S. aureus exhibiting decreased susceptibility to different antibiotics like vancomycin, daptomycin, and linezolid severely compromise the therapeutic alternatives and require a considerable amount of time, public awareness, and integrative health-care strategies to prevent the emergence of resistance to these compounds
Self-Controlled Hyperthermia & MRI Contrast Enhancement via Iron Oxide Embedded Hydroxyapatite Superparamagnetic particles for Theranostic Application
Increasing effectiveness of cancer
therapeutics requires a multipronged
approach. Delivery of controlled hyperthermia in the ranges of 43
to 45 °C on site aided by superparamagnetic particles ensures
cell death via the apoptosis pathway.We demonstrated the use of iron-oxide
embedded hydroxyapatite (HAIO) superparamagnetic particles for delivery
of controlled hyperthermia and contrast enhancement in MRI. To determine
optimal hyperthermia delivery, we used 5 and 10 mg/mL concentrations
of HAIO on various magnetic fields in alternating magnetic field (AMF)
study. Time–temperature profile and specific loss power (SLP)
data revealed that HAIO delivered precisely controlled temperature
in contrast to superparamagnetic iron oxide nanoparticles (SPIONs).
Earlier studies had demonstrated that HAIO concentrations of 0.5 to
3 mg/mL are cytocompatible. Exposure of HeLa cells to HAIO at a concentration
of 2 mg/mL and applied field of 33.8 mT for a period of 30 min resulted
in apoptosis induction in 75% of population. Significant cellular
disruption was affirmed via FACS, ESEM and cLSM techniques. An aqueous
phantom study and <i>in vitro</i> cell culture study evaluation
indicated relaxivity of 50.92 mM<sup>–1</sup> s<sup>–1</sup> and good pixel intensity variation in MRI. The current study assesses
the potential of HAIO to deliver controlled hyperthermia and act as
a negative MRI contrast agent. Repeated experiments have confirmed
enhanced utility of the technique in the burgeoning field of theranostics
Periapical tissue reaction to calcium phosphate root canal sealer in porcine model
Background: Calcium phosphate cements (CPC) are a group of biomaterials possessing wide scope of use in various branches of medical science. These materials have been proposed to be highly biocompatible and osteoconductive. This study is based on a newly developed CPC formulation (Chitra-CPC) and is aimed at the evaluation of its biocompatibility through an Endodontic Usage Test in a porcine study model.
Objective: To evaluate the periapical tissue reaction to Chitra-CPC when used as a root canal sealer/filler material in comparison with a resin sealer, AH Plus (Dentsply).
Materials and Methods: The procedure was done on porcine animal model following the ISO 7405 criteria. The material was implanted intentionally into the periapical area of 36 teeth through a root canal procedure carried out in six animals which were divided equally among 1-month and 3-month time periods. Results were based on the histological evaluation of the autopsied specimens after the prescribed time periods.
Results: Mild to moderate periapical tissue reaction was found in Chitra-CPC samples belonging to the 1-month time period, whereas majority of the 3-month CPC samples showed an absence of inflammation. Samples of AH Plus in 1-month period showed severe to moderate inflammation, whereas 3-month AH Plus samples had a mild to moderate inflammation.
Conclusions: Chitra-CPC is a biocompatible material