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1.
J Am Vet Med Assoc ; 262(3): 426-431, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-37922712

ABSTRACT

The purpose of this viewpoint is to discuss the risks associated with offering clinic-backed payment plans, with a particular focus on financial risks. We provide a financial calculator tool that clinics can use with their financial information to make more informed decisions about whether implementing clinic-backed payment plans are viable for them. Realistic but hypothetical financial information for a clinic is used to simulate financial evaluations, including cash flow budget analysis, multivariate sensitivity analysis, and risk assessment to help clinics better understand these evaluations. Our simulations show that even under high default rates, the revenue benefits outweigh the labor costs and could bring higher profitability to clinics while increasing access to care for clients and patients.


Subject(s)
Veterinary Medicine , Veterinary Medicine/economics
2.
Science ; 375(6586): 1205, 2022 Mar 18.
Article in English | MEDLINE | ID: mdl-35298258

ABSTRACT

In 2016, the US Congress enacted the Puerto Rico Oversight, Management, and Economic Stability Act (PROMESA), which led to a federally appointed Financial Oversight and Management Board (FOMB) to oversee restructuring of the island's $74 billion debt and achieve sustainable budgets. Many economists argue that even debt adjustment, which was approved in January, will not be enough to put Puerto Rico on a road to recovery. Unprecedented budget cuts by FOMB have already reduced funding from Puerto Rico's state government for the University of Puerto Rico (UPR). UPR is the island's premier institute of higher learning in science, technology, engineering, and mathematics (STEM). State funding for UPR must be restored if Puerto Rico is to stably recover from years of economic despair.

3.
J Vet Med Educ ; 49(4): 484-491, 2022 Aug.
Article in English | MEDLINE | ID: mdl-34102093

ABSTRACT

Veterinary staff must be able to navigate end-of-life care with sensitivity and skill to create the best possible outcome for the patient, client, and veterinary team collectively. Despite the clear importance of euthanasia communication and procedural skills in veterinary practice, recent graduates of veterinary programs identified gaps between skills deemed important in clinical practice and skills emphasized in the curriculum. Little time is allocated to euthanasia procedural or communication training across the board in US veterinary programs. Thus, it is of paramount importance to establish intentional and well-designed instruction and assessment of euthanasia communication skills for veterinary trainees. A course on veterinary euthanasia communication skills was designed to emphasize themes and topics essential for a competent veterinarian. Through course evaluations, students expressed the sentiments that this course improved their euthanasia communication skills, that euthanasia communication skills are essential for their careers, and that the course content should be integrated into the core curriculum. This article presents a scaffold for the instruction and assessment of veterinary euthanasia communication skills in alignment with a competency-based veterinary education (CBVE) framework and outlines specific learning interventions used in the course that are scalable and may be extracted and incorporated into existing courses.


Subject(s)
Education, Veterinary , Veterinarians , Animals , Communication , Curriculum , Euthanasia, Animal , Humans
4.
Nanomaterials (Basel) ; 10(5)2020 Apr 26.
Article in English | MEDLINE | ID: mdl-32357400

ABSTRACT

Zirconium phosphate (ZrP) nanomaterials have been studied extensively ever since the preparation of the first crystalline form was reported in 1964. ZrP and its derivatives, because of their versatility, have found applications in several fields. Herein, we provide an overview of some advancements made in the preparation of ZrP nanomaterials, including exfoliation and morphology control of the nanoparticles. We also provide an overview of the advancements made with ZrP as an inorganic support for the electrocatalysis of the oxygen evolution reaction (OER). Emphasis is made on how the preparation of the ZrP electrocatalysts affects the activity of the OER.

5.
Dalton Trans ; 49(13): 3914-3916, 2020 04 01.
Article in English | MEDLINE | ID: mdl-32154526
6.
Dalton Trans ; 49(12): 3892-3900, 2020 Mar 24.
Article in English | MEDLINE | ID: mdl-31894216

ABSTRACT

The electrochemical oxygen evolution reaction (OER) is the half-cell reaction for many clean-energy production technologies, including water electrolyzers and metal-air batteries. However, its sluggish kinetics hinders the performance of those technologies, impeding them from broader implementation. Recently, we reported the use of zirconium phosphate (ZrP) as a support for transition metal catalysts for the oxygen evolution reaction (OER). These catalysts achieve promising overpotentials with high mass activities. Herein, we synthesize ZrP structures with controlled morphology: hexagonal platelets, rods, cubes, and spheres, and subsequently modify them with Co(ii) and Ni(ii) cations to assess their electrochemcial OER behavior. Through inductively coupled plasma mass-spectrometry measurements, the maximum ion exchange capacity is found to vary based on the morphology of the ZrP structure and cation selection. Trends in geometric current density and mass activity as a function of cation selection are discussed. We find that the loading and coverage of cobalt and nickel species on the ZrP supports are key factors that control OER performance.

7.
Science ; 362(6410): 7, 2018 10 05.
Article in English | MEDLINE | ID: mdl-30287637
10.
Magn Reson Chem ; 55(7): 648-654, 2017 Jul.
Article in English | MEDLINE | ID: mdl-27966256

ABSTRACT

Several layered zirconium phosphates treated with Zr(IV) ions, modified by monomethoxy-polyethyleneglycol-monophosphate and intercalated with doxorubicin hydrochloride have been studied by solid-state MAS NMR techniques. The organic components of the phosphates have been characterized by the 13 C{1 H} CP MAS NMR spectra compared with those of initial compounds. The multinuclear NMR monitoring has provided to establish structure and covalent attachment of organic/inorganic moieties to the surface and interlayer spaces of the phosphates. The MAS NMR experiments including kinetics of proton-phosphorus cross polarization have resulted in an unusual structure of zirconium phosphate 6 combining decoration of the phosphate surface by polymer units and their partial intercalation into the interlayer space. Copyright © 2016 John Wiley & Sons, Ltd.


Subject(s)
Zirconium/chemistry , Doxorubicin/chemistry , Magnetic Resonance Spectroscopy , Polyethylene Glycols/chemistry , Surface Properties
11.
J Nanosci Nanotechnol ; 16(1): 117-29, 2016 Jan.
Article in English | MEDLINE | ID: mdl-27398437

ABSTRACT

Zirconium phosphate (ZrP) nanoplatelets can intercalate anticancer agents via an ion exchange reaction creating an inorganic delivery system with potential for cancer treatment. ZrP delivery of anticancer agents inside tumor cells was explored in vitro. Internalization and cytotoxicity of ZrP nanoplatelets were studied in MCF-7 and MCF-10A cells. DOX-loaded ZrP nanoplatelets (DOX@ZrP) uptake was assessed by confocal (CLSM) and transmission electron microscopy (TEM). Cytotoxicity to MCF-7 and MCF-10A cells was determined by the MTT assay. Reactive Oxy- gen Species (ROS) production was analyzed by fluorometric assay, and cell cycle alterations and induction of apoptosis were analyzed by flow cytometry. ZrP nanoplatelets were localized in the endosomes of MCF-7 cells. DOX and ZrP nanoplatelets were co-internalized into MCF-7 cells as detected by CLSM. While ZrP showed limited toxicity to MCF-7 cells, DOX@ZrP was cytotoxic at an IC50 similar to that of free DOX. Meanwhile, DOX lC50 was significantly lower than the equivalent concentration of DOX@ZrP in MCF-10A cells. ZrP did not induce apoptosis in both cell lines. DOX and DOX@ZrP induced significant oxidative stress in both cell models. Results suggest that ZrP nanoplatelets are promising as carriers of anticancer agents into cancer cells.


Subject(s)
Apoptosis/drug effects , Doxorubicin , Drug Carriers , Nanoparticles/chemistry , Neoplasms/drug therapy , Zirconium , Doxorubicin/chemistry , Doxorubicin/pharmacology , Drug Carriers/chemistry , Drug Carriers/pharmacology , Female , Humans , MCF-7 Cells , Neoplasms/metabolism , Neoplasms/pathology , Zirconium/chemistry , Zirconium/pharmacology
12.
Science ; 349(6253): 1145, 2015 Sep 11.
Article in English | MEDLINE | ID: mdl-26359377
13.
Opt Lett ; 40(14): 3300-3, 2015 Jul 15.
Article in English | MEDLINE | ID: mdl-26176454

ABSTRACT

Imaging deep tissue can be extremely inefficient when the region of interest is nonplanar and buried in a thick sample, yielding a severely limited effective field-of-view (FOV). Here we describe a novel technique, namely adaptive field microscopy, which improves the efficiency of 3D imaging by controlling the image plane. The plane of scanning laser focus is continuously reshaped in situ to match the conformation of the sample. The practicality is demonstrated for ophthalmic imaging, where a large area of the corneal epithelium of intact mouse eye is captured in a single frame with subcellular resolution.


Subject(s)
Imaging, Three-Dimensional/methods , Microscopy, Confocal/methods , Animals , Eye/cytology , HeLa Cells , Humans , Mice
14.
Nanoscale ; 5(23): 11456-63, 2013 Dec 07.
Article in English | MEDLINE | ID: mdl-24072038

ABSTRACT

We report the use of zirconium phosphate (ZrP) nanoplatelets for the encapsulation of the anticancer drug cisplatin and its delivery to tumor cells. Cisplatin was intercalated into ZrP by direct ion exchange and was tested in vitro for cytotoxicity in the human breast cancer (MCF-7) cell line. The structural characterization of the intercalated cisplatin in ZrP suggests that during the intercalation process, the chloride ligands of the cisplatin complex were substituted by phosphate groups within the layers. Consequently, a new phosphate phase with the platinum complex directly bound to ZrP (cisPt@ZrP) is produced with an interlayer distance of 9.3 Å. The in vitro release profile of the intercalated drug upon a pH stimulus shows that at low pH under lysosomal conditions the platinum complex is released with simultaneous hydrolysis of the zirconium phosphate material, while at higher pH the complex is not released. Experiments with the MCF-7 cell line show that cisPt@ZrP reduced the cell viability up to 40%. The cisPt@ZrP intercalation product is envisioned as a future nanotherapy agent against cancer. Taking advantage of the shape and sizes of the ZrP particles and controlled release of the drug at low pH, it is intended to exploit the enhanced permeability and retention effect of tumors, as well as their intrinsic acidity, for the destruction of malignant cells.


Subject(s)
Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Cisplatin/chemistry , Cisplatin/pharmacology , Intercalating Agents/chemistry , Metal Nanoparticles/chemistry , Zirconium/chemistry , Antineoplastic Agents/administration & dosage , Breast Neoplasms/drug therapy , Cell Survival/drug effects , Cisplatin/administration & dosage , Drug Carriers/chemistry , Female , Humans , Hydrogen-Ion Concentration , Intercalating Agents/pharmacology , MCF-7 Cells
15.
Inorg Chem ; 51(5): 2777-84, 2012 Mar 05.
Article in English | MEDLINE | ID: mdl-22339702

ABSTRACT

The direct intercalation of a pyrazolate-bridged platinum(II) bipyridyl dimer ([{Pt(dmbpy)(µ-pz)}(2)](2+); dmbpy = 4,4'-dimethyl-2,2'-bipyridine, pz(-) = pyrazolate) within a zirconium phosphate (ZrP) framework has been accomplished. The physical and spectroscopic properties of [{Pt(dmbpy)(µ-pz)}(2)](2+) intercalated in ZrP were investigated by X-ray powder diffraction and X-ray photoelectron, infrared, absorption, and luminescence spectroscopies. Zirconium phosphate layers have a special microenvironment that is capable of supporting a variety of platinum oxidation states. Diffuse reflectance spectra from powders of the blue-gray intercalated materials show the formation of a low-energy band at 600 nm that is not present in the platinum dimer salt. The nonintercalated complex is nonemissive in room-temperature fluid solution, but gives rise to intense blue-green emission in a 4:1 ethanol/methanol 77 K frozen glassy solution. Powders and colloidal suspensions of [{Pt(dmbpy)(µ-pz)}(2)](2+)-exchanged ZrP materials exhibit intense emissions at room-temperature.

16.
Langmuir ; 28(9): 4447-52, 2012 Mar 06.
Article in English | MEDLINE | ID: mdl-22316317

ABSTRACT

The direct intercalation reaction of [Co(tpy)(2)](2+) with the highly hydrated θ phase of layered zirconium phosphate (θ-ZrP) resulted in the formation of the oxidized [Co(tpy)(2)](3+) ion within the ZrP material. The X-ray powder diffraction patterns showed that the interlayer distance increases from 10.3 Å in θ-ZrP to 14.9 Å in the dry [Co(tpy)(2)](3+)-intercalated ZrP {[Co(tpy)(2)](3+):ZrP} phase. The complex remains electroactive within the layers of ZrP. The formal potential of a carbon paste electrode (CPE) modified with [Co(tpy)(2)](3+):ZrP (E°' = 40.8 mV versus Ag/AgCl, 3.5 M NaCl) is non-pH-dependent. However, the sensitivity of the [Co(tpy)(2)](3+):ZrP-modified CPE for the detection of reduced nicotinamide adenine dinucleotide (NADH) electrooxidation was lower than that of a previously reported CPE modified with [Ru(phend)(2)bpy](2+)-intercalated ZrP. (1) To improve the characteristics of NADH electrooxidation of the [Co(tpy)(2)](3+):ZrP-modified CPE, we included the enzyme diaphorase in solution, which increased the electrocatalytic current for NADH oxidation. A bienzymatic lactate biosensor was constructed and used for lactate sensing.


Subject(s)
Biosensing Techniques/methods , Cobalt/chemistry , Zirconium/chemistry , Catalysis , NAD/chemistry , X-Ray Diffraction
17.
Chem Commun (Camb) ; 48(12): 1754-6, 2012 Feb 07.
Article in English | MEDLINE | ID: mdl-22218458

ABSTRACT

Doxorubicin was intercalated into novel zirconium phosphate nano-platelets (ZrP). The obtained doxorubicin intercalated ZrP nano-platelets had an impressive 34.9% (w/w) drug loading. We used this material to deliver doxorubicin to breast cancer cells (MCF-7). Cellular studies with MCF-7 cells showed higher uptake and cytotoxicity of doxorubicin loaded ZrP compared to free doxorubicin.


Subject(s)
Antibiotics, Antineoplastic/administration & dosage , Doxorubicin/administration & dosage , Drug Carriers/chemistry , Nanostructures/chemistry , Zirconium/chemistry , Antibiotics, Antineoplastic/pharmacology , Breast Neoplasms/drug therapy , Cell Line, Tumor , Cell Survival/drug effects , Doxorubicin/pharmacology , Female , Humans , Nanostructures/ultrastructure
18.
Inorg Chem ; 49(16): 7298-303, 2010 Aug 16.
Article in English | MEDLINE | ID: mdl-20690739

ABSTRACT

We studied the structures, luminescence, and self-quenching properties of tris(2,2'-bipyridyl)ruthenium(II) (Ru(bpy)(3)(2+)) two-dimensional arrangements within the layers of zirconium phosphate (ZrP). The intercalation of Ru(bpy)(3)(2+) was accomplished using a hydrated form of zirconium phosphate ZrP. Varying the Ru(bpy)(3)(2+)/ZrP intercalation ratio, different Ru(bpy)(3)(2+)-exchanged ZrP loading levels were achieved. The ion exchange of Ru(bpy)(3)(2+) within ZrP produces a red shift in the metal-to-ligand charge-transfer (MLCT) absorption band of the complex from 452 nm in aqueous solution to 460 nm in ZrP. Steady state luminescence spectra of the Ru(bpy)(3)(2+)-exchanged ZrP materials show an increase in the luminescence intensity with an increase in the Ru(bpy)(3)(2+) loading level until about 0.77 M, where subsequent increases in the loading level produce a decrease in the luminescence (self-quenching region). Time-resolved luminescence measurements are consistent with the steady state luminescence measurements. Analysis of the time domain luminescence measurements in loadings higher than 0.77 M leads to the determination of a collisional quenching rate constant of (1.67 +/- 0.05) x 10(6) M(-1) s(-1). Stern-Volmer analysis of the luminescence quantum yield of Ru(bpy)(3)(2+)-exchanged ZrP materials indicates that static quenching is also involved in the Ru(bpy)(3)(2+) self-quenching mechanism. The quantum yield data behavior might be explained by a model that takes into account collisional quenching and the quasi-static Perrin mechanism. The calculation yields a quenching sphere of action of 14.8 A, which is slightly larger than the collisional radii of two Ru(bpy)(3)(2+) ions (12.2 A), as predicted by the model.


Subject(s)
Organometallic Compounds/chemistry , Zirconium/chemistry , Coordination Complexes , Luminescent Measurements , Quantum Theory , Spectrum Analysis
19.
Biomacromolecules ; 11(9): 2465-70, 2010 Sep 13.
Article in English | MEDLINE | ID: mdl-20707305

ABSTRACT

The encapsulation of insulin into different kinds of materials for noninvasive delivery is an important field of study because of the many drawbacks of painful needle and syringe delivery such as physiological stress, infection, and local hypertrophy, among others (Khafagy, E.-S.; et al. Adv. Drug Delivery Rev. 2007, 59 (15), 1521-1546). A stable, robust, nontoxic, and viable noninvasive carrier for insulin delivery is needed. We present a new approach for protein nanoencapsulation using layered zirconium phosphate (ZrP) nanoparticles produced without any preintercalator present. The use of ZrP without preintercalators produces a highly pure material, without any kinds of contaminants, such as the preintercalator, which can be noxious. Cytotoxicity cell viability in vitro experiments for the ZrP nanoparticles show that ZrP is not toxic, or harmful, in a biological environment, as previously reported for rats (Zhu, Z. Y.; et al. Mater. Sci. Forum 2009, 620-622, 307-310). Contrary to previous preintercalator-based methods, we show that insulin can be nanoencapsulated in ZrP if a highly hydrate phase of ZrP with an interlayer distance of 10.3 Å (10.3 Å-ZrP or θ-ZrP) is used as a precursor. The intercalation of insulin into ZrP produced a new insulin-intercalated ZrP phase with about a 27 A interlayer distance, as determined by X-ray powder diffraction, demonstrating a successful nanoencapsulation of the hormone. The in vitro release profile of the hormone after the intercalation was determined and circular dichroism was used to study the hormone stability upon intercalation and release. The insulin remains stable in the layered material, at room temperature, for a considerable amount of time, improving the shell life of the peptidic hormone. This type of material represents a strong candidate to developing a noninvasive insulin carrier for the treatment of diabetes mellitus.


Subject(s)
Hypoglycemic Agents/chemistry , Insulin/chemistry , Intercalating Agents/chemistry , Nanocapsules/chemistry , Nanotechnology/methods , Zirconium/chemistry , Animals , Breast Neoplasms/drug therapy , Cattle , Cell Survival/drug effects , Circular Dichroism , Female , Humans , Hypoglycemic Agents/pharmacology , Insulin/pharmacology , Microscopy, Electron, Scanning , Pancreas/metabolism , Rats , Spectroscopy, Fourier Transform Infrared , Tumor Cells, Cultured
20.
Biochemistry ; 48(22): 5018-25, 2009 Jun 09.
Article in English | MEDLINE | ID: mdl-19368336

ABSTRACT

Nitrosyl hydride, HNO or nitroxyl, is the one-electron reduced and protonated form of nitric oxide. HNO is isoelectronic to singlet O(2), and we have previously reported that deoxymyoglobin traps free HNO to form a stable adduct. In this report, we demonstrate that oxygen-binding hemoglobins from human, soy, and clam also trap HNO to form adducts which are stable over a period of weeks. The same species can be formed in higher yields by careful reduction of the ferrous nitrosyl adducts of the proteins. Like the analogous O(2)-Fe(II) adducts, the HNO adducts are diamagnetic, but with a characteristic HNO resonance in (1)H NMR at ca. 15 ppm that splits into doublets for H(15)NO adducts. The (1)H and (15)N NMR resonances, obtained by HSQC experiments, are shown to differentiate subunits and isoforms of proteins within mixtures. An apparent difference in the reduction rates of the NO adducts of the two subunits of human hemoglobin allows assignment of two distinct nitrosyl hydride peaks by a combination of UV-vis, NMR, and EPR analysis. The two peaks of the HNO-hHb adduct have a persistent 3:1 ratio during trapping reactions, demonstrating a kinetic difference between HNO binding at the two subunits. These results show NMR characterization of ferrous HNO adducts as a unique tool sensitive to structural changes within the oxygen-binding cavity, which may be of use in defining modes of oxygen binding in other heme proteins and enzymes.


Subject(s)
Ferrous Compounds/chemistry , Globins/chemistry , Oxygen/chemistry , Animals , Bivalvia , Hemeproteins/chemistry , Hemoglobins/chemistry , Horses , Humans , Hydroxamic Acids/chemistry , Myoglobin/chemistry , Nitroso Compounds/chemistry , Nuclear Magnetic Resonance, Biomolecular , Protons , Sulfonamides/chemistry
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