One Dimensional Experimental Setup to Study the Heating of Nanoparticle Laden Systems

2010 ◽  
Author(s):  
Zhenpeng Qin ◽  
John C. Bischof
Keyword(s):  
Small Volume ◽  
Laser Energy ◽  
Special Kind ◽  
Gold Nanoshells ◽  
Experimental Setup ◽  
Heat Absorption ◽  
One Dimensional ◽  
Lumped Models

Intensive efforts have been put into the use of gold nanoparticles (GNPs) for the enhancement of hyperthermia using laser in recent years since the groundbreaking work of Hirsh et al.(1) using gold nanoshells (GNS). Both in vitro (2), and in vivo (3) studies show promising results. For example, GNS, a special kind of GNP, are being manufactured and are in clinical trials (Nanospectra Bioscience, Inc). While the data is compelling, unfortunately the fundamentals of GNP heating are not entirely understood. For example, there are large discrepancies in the experimentally measured photothermal efficiency of GNPs (4, 5). Furthermore, lumped models of GNP heating in solution, by using small volume of GNP solution (4, 5), or stirring the solution (6), neglecting the variation of heat absorption throughout a system require improvement. In reality, the GNPs will attenuate the laser beam as it passes through the GNP host medium. GNPs at different locations will absorb different amount of laser energy and hence have different heat generation.

scholarly journals Application of the 1-µsec pulsed-dye laser to the treatment of experimental cerebral vasospasm

1991 ◽  
Vol 75 (2) ◽  
pp. 271-276 ◽  
Author(s):  
Atsushi Teramura ◽  
Robert Macfarlane ◽  
Christopher J. Owen ◽  
Ralph de la Torre ◽  
Kenton W. Gregory ◽  
...  
Keyword(s):  
Cerebral Vasospasm ◽  
Basilar Artery ◽  
Laser Energy ◽  
Autologous Blood ◽  
Preliminary Investigation ◽  
Dye Laser ◽  
Pulsed Dye Laser ◽  
Content Type

✓ Laser energy of 480 nm was applied in 1-µsec pulses varying between 2.2 and 10 mJ to in vitro and in vivo models of cerebral vasospasm. First, the pulsed-dye laser was applied intravascularly via a 320-µm fiber to basilar artery segments from six dogs. The segments were mounted in a vessel-perfusion apparatus and constricted to, on average, 70% of resting diameter by superfusion with dog hemolysate. Immediate increase in basilar artery diameter occurred to a mean of 83% of control. In a second model, the basilar artery was exposed transclivally in the rabbit. In three normal animals, superfusion of the artery with rabbit hemolysate resulted in a reduction of mean vessel diameter to 81% of control. Following extravascular application of the laser, vessels returned to an average of 106% of the resting state. In six rabbits, the basilar artery was constricted by two intracisternal injections of autologous blood, 3 days apart. Two to 4 days after the second injection, the basilar artery was exposed. Extravascular laser treatment from a quartz fiber placed perpendicular to the vessel adventitia resulted in an immediate 53% average increase in caliber to an estimated 107% of control. No reconstriction was observed over a period of up to 5 hours. Morphologically, damage to the arterial wall was slight. This preliminary investigation suggests that the 1-µsec pulsed-dye laser may be of benefit in the treatment of cerebral vasospasm.

Evaluation of the Toxicity of Intravenous Delivery of Auroshell Particles (Gold–Silica Nanoshells)

2012 ◽  
Vol 31 (6) ◽  
pp. 584-594 ◽  
Author(s):  
Shayne C. Gad ◽  
Kelly L. Sharp ◽  
Charles Montgomery ◽  
J. Donald Payne ◽  
Glenn P. Goodrich
Keyword(s):  
Water Solution ◽  
Chinese Hamster Ovary Cells ◽  
Chinese Hamster ◽  
Gold Nanoshells ◽  
Sprague Dawley ◽  
Ovary Cells ◽  
Good Laboratory ◽  
Chromosomal Aberration Assay

Gold nanoshells (155 nm in diameter with a coating of polyethylene glycol 5000) were evaluated for preclinical biocompatibility, toxicity, and biodistribution as part of a program to develop an injectable device for use in the photothermal ablation of tumors. The evaluation started with a complete good laboratory practice (GLP) compliant International Organization for Standardization (ISO)-10993 biocompatibility program, including cytotoxicity, pyrogenicity (US Pharmacopeia [USP] method in the rabbit), genotoxicity (bacterial mutagenicity, chromosomal aberration assay in Chinese hamster ovary cells, and in vivo mouse micronucleus), in vitro hemolysis, intracutaneous reactivity in the rabbit, sensitization (in the guinea pig maximization assay), and USP/ISO acute systemic toxicity in the mouse. There was no indication of toxicity in any of the studies. Subsequently, nanoshells were evaluated in vivo by intravenous (iv) infusion using a trehalose/water solution in a series of studies in mice, Sprague-Dawley rats, and Beagle dogs to assess toxicity for time durations of up to 404 days. Over the course of 14 GLP studies, the gold nanoshells were well tolerated and, when injected iv, no toxicities or bioincompatibilities were identified.

A sensitive HPLC-FL method to simultaneously determine febuxostat and diclofenac in rat plasma: assessment of metabolic drug interactions in vitro and in vivo

2020 ◽  
Vol 12 (16) ◽  
pp. 2166-2175 ◽  
Author(s):  
Dong-Gyun Han ◽  
Kyu-Sang Kim ◽  
Seong-Wook Seo ◽  
Young Mee Baek ◽  
Yunjin Jung ◽  
...  
Keyword(s):  
Sample Preparation ◽  
Drug Interactions ◽  
Simultaneous Determination ◽  
Small Volume ◽  
Rat Plasma ◽  
Metabolic Drug ◽  
Simple Sample Preparation

We developed a sensitive, simple and validated HPLC-FL method for simultaneous determination of FEB and DIC in rat plasma. The method requires a relatively small volume of sample, has simple sample preparation and excellent sensitivity.

scholarly journals Torque Loss After Miniscrew Placement: An In-Vitro Study Followed by a Clinical Trial

2016 ◽  
Vol 10 (1) ◽  
pp. 251-260 ◽  
Author(s):  
Marco Migliorati ◽  
Sara Drago ◽  
Fabrizio Barberis ◽  
Irene Schiavetti ◽  
Domenico Dalessandri ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Insertion Time ◽  
Controlled Environment ◽  
Insertion Torque ◽  
Experimental Setup ◽  
Percentage Difference ◽  
Torque Loss ◽  
Torque Values

To evaluate torque loss a week after insertion, both in an in vivo and an in vitro experimental setup were designed. In the in vivo setup a total of 29 miniscrews were placed in 20 patients who underwent orthodontic treatment. Maximum insertion torque (MIT) was evaluated at insertion time (T1). A week later, insertion torque was measured again by applying a quarter turn (T2); no load was applied on the screw during the first week. In the in vitro setup a total of 20 miniscrews were placed in pig rib bone samples. MIT was evaluated at insertion time (T1). Bone samples were kept in saline solution and controlled environment for a week during which the solution was refreshed every day. Afterwards, torque was measured again by applying a quarter turn (T2). The comparison of MIT over time was done calculating the percentage difference of the torque values between pre- and post-treatment and using the parametric two independent samples t-test or the non-parametric Mann–Whitney test. After a week unloaded miniscrews showed a mean loss of rotational torque of 36.3% and 40.9% in in vitro and in in vivo conditions, respectively. No statistical differences were found between the two different setups. Torque loss was observed after the first week in both study models; in vitro experimental setup provided a reliable study model for studying torque variation during the first week after insertion.

scholarly journals Single-unit transfusions of RBC enzymatically converted from group B to group O to A and O normal volunteers

Blood ◽  
1991 ◽  
Vol 77 (6) ◽  
pp. 1383-1388 ◽  
Author(s):  
LL Lenny ◽  
R Hurst ◽  
J Goldstein ◽  
LJ Benjamin ◽  
RL Jones
Keyword(s):  
Single Unit ◽  
Small Volume ◽  
Survival Times ◽  
Chronic Anemia ◽  
Group A ◽  
Alpha Galactosidase ◽  
Group B ◽  
Sustained Increase

Abstract Full-unit transfusions of RBC enzymatically converted from group B to group O by treatment with alpha-galactosidase (ECO RBC) to group O and A normal healthy individuals exhibit excellent in vivo survival times (24-hour survival 95.1% +/- 2.3%, T50 36.9 +/- 4.6 days). These results confirm our earlier findings describing ECO RBC in vitro viability and normal in vivo survival time after small-volume infusions. No significant increase in pretransfusion anti-B titer or score is observed in either group O or A subjects provided that sufficient enzyme is used to treat the cells: Cells transfused to group O recipients require higher levels of enzyme (185 to 200 U/mL RBC) than those infused to group A (90 U/mL RBC). Two separate single-unit transfusions of ECO RBC to one group O recipient (4.5 months apart) also survived normally (24-hour survival 96% and 92%, T50 40 and 36 days) and did not increase preexisting anti-B levels in this subject. ECO RBC were not agglutinated or lysed by recipient sera before or after transfusion. Similarly, no antibody development to the alpha- galactosidase used in cell treatment (and washed from the product before transfusion) could be detected in any subject. The sustained increase in hemoglobin levels after transfusion of ECO RBC suggests that this product will be useful in treatment of acute and chronic anemia.

The synergistic effect of chemo-photothermal therapies in SN-38-loaded gold-nanoshell-based colorectal cancer treatment

Nanomedicine ◽  
2021 ◽  
Author(s):  
Shu-Jyuan Yang ◽  
Hsiao-Ting Huang ◽  
Chung-Huan Huang ◽  
Jui-An Pai ◽  
Chung-Hao Wang ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Photothermal Therapy ◽  
Near Infrared ◽  
Gold Nanoshells ◽  
Au Nps ◽  
Tumor Mouse Model ◽  
Tumor Clearance ◽  
Tumor Growth Suppression

Aim: 7-Ethyl-10-hydroxycamptothecin (SN-38)-loaded gold nanoshells nanoparticles (HSP@Au NPs) were developed for combined chemo-photothermal therapy to treat colorectal cancer. Materials & methods: SN-38-loaded nanoparticles (HSP NPs) were prepared by the lyophilization-hydration method, and then developed into gold nanoshells. The nanoparticles were characterized and assessed for photothermal properties, cytotoxicity and hemocompatibility in vitro. In vivo anticancer activity was tested in a tumor mouse model. Results: The HSP@Au NPs (diameter 186.9 nm, zeta potential 33.4 mV) led to significant cytotoxicity in cancer cells exposed to a near-infrared laser. Moreover, the HSP@Au NP-mediated chemo-photothermal therapy displayed significant tumor growth suppression and disappearance (25% of tumor clearance rate) without adverse side effects in vivo. Conclusion: HSP@Au NPs may be promising in the treatment of colorectal cancer in the future.

scholarly journals Construction of a novel microfluidic experimental setup for testing recent glaucoma drainage devices

2019 ◽  
Vol 5 (1) ◽  
pp. 219-222
Author(s):  
Emre Kara ◽  
Ahmet İhsan Kutlar ◽  
Kıvanç Güngör
Keyword(s):  
Flow Behavior ◽  
Pressure Sensors ◽  
Control Unit ◽  
Pressure Control ◽  
World Health ◽  
Experimental Setup ◽  
Great Effort ◽  
Glaucoma Drainage Devices

AbstractGlaucoma is an eye disorder in which the optic nerve is damaged over time due to a sustained elevation of the intraocular pressure (IOP). Being the second leading cause of blindness according to the reports of the World Health Organization, glaucoma is not only a serious ocular disease that threatens individuals, but also a community health problem. In recent years, great improvement has been achieved in the technology of implants used in the treatment of the disease. Despite the great effort dedicated to the design and implementation of the glaucoma drainage devices (GDD), they still have unsolved problems and weaknesses. Most of the currently employed GDDs are very simple and have major problems such as reversed flow, choking and a coarse interval of pressure control. Experiments must be devised to investigate the flow behavior inside these devices. In this study, an accurate microfluidics experimental setup is constructed to analyze and characterize the in-vitro performance of actively employed GDDs on the glaucoma treatment. Proposed setup includes a pressurized fluid reservoir, ELVEFLOW microfluidics flow rate measurement/control unit, microfluidics flow/pressure sensors, and data analysis system. In the setup, more precise measurements than experimental setups in literature is planned to be provided. It is estimated that the results showing consistency with in-vivo measurements will be obtained, behavior of the fluid passing through the GDDs will be observed and issues with design flaws will be addressed.

scholarly journals Alteration in proportions of histone H1 variants during the differentiation of murine erythroleukaemic cells

1992 ◽  
Vol 288 (3) ◽  
pp. 747-751 ◽  
Author(s):  
W Helliger ◽  
H Lindner ◽  
O Grübl-Knosp ◽  
B Puschendorf
Keyword(s):  
Sodium Butyrate ◽  
Gel Electrophoresis ◽  
Histone H1 ◽  
Dimethyl Sulphoxide ◽  
Strong Increase ◽  
Reverse Phase ◽  
One Dimensional ◽  
Modest Increase

We have investigated the changes in the relative amounts of histone H1 zero and all five H1 variants during the differentiation in vitro of Friend erythroleukaemic cells. Three different agents were used as inducers of differentiation: dimethyl sulphoxide, hexamethylenebisacetamide and sodium butyrate. By applying a combination of reverse-phase h.p.l.c. and one-dimensional gel electrophoresis we observed that, during differentiation in vitro, (1) the relative amount of each subtype changes upon induction and that (2) dimethyl sulphoxide and hexamethylenebisacetamide produce a similar histone H1 pattern with a strong increase in histones H1 zero and H1c, a modest increase in histone H1e and a decrease in the relative amounts of histone H1a, H1b and H1d, whereas butyrate induces a different pattern, particularly with respect to both histones H1c and H1e: H1c increased slightly, and H1e strongly, during differentiation. These results are compared with changes in the histone H1 pattern during differentiation in vivo in the mouse [Lennox & Cohen (1983) J. Biol. Chem. 258, 262-268] and in the rat [Pina, Martinez & Suau (1987) Eur. J. Biochem. 164, 71-76], and similarities and deviations are discussed.

scholarly journals A review of the in vitro and in vivo valved holding chamber (VHC) literature with a focus on the AeroChamber Plus Flow-Vu Anti-static VHC

2018 ◽  
Vol 12 ◽  
pp. 175346581775134 ◽  
Author(s):  
Sanjeeva Dissanayake ◽  
Jason Suggett
Keyword(s):  
Small Volume ◽  
Metered Dose Inhalers ◽  
Drug Deposition ◽  
Aerosol Performance ◽  
Regulatory Guidelines ◽  
Metered Dose ◽  
Vulnerable Patient ◽  
Patient Groups

Valved holding chambers (VHCs) reduce the need for inhalation-actuation coordination with pressurized metered dose inhalers (pMDIs), reduce oropharyngeal drug deposition and may improve lung deposition and clinical outcomes compared to pMDIs used alone. While VHCs are thus widely advocated for use in vulnerable patient groups within clinical and regulatory guidelines, there is less consensus as to whether the performance differences between different VHCs have clinical implications. This review evaluates the VHC literature, in particular the data pertaining to large- versus small-volume chambers, aerosol performance with a VHC adjunct versus a pMDI alone, charge dissipative/conducting versus non-conducting VHCs, and facemasks, to ascertain whether potentially meaningful differences between VHCs exist. Inconsistencies in the literature are examined and explained, and relationships between in vitro and in vivo data are discussed. A particular focus of this review is the AeroChamber Plus® Flow-Vu® Anti-static VHC, the most recent iteration of the AeroChamber VHC family.

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