Inhibitors of intracellular chloride regulation induces cisplatin resistance in canine osteosarcoma cells

The objective of this study was to examine the role of ion transport mechanisms in clinical anticancer drug resistance. Reduction in intracellular accumulation of cisplatin is believed to be an early change in cisplatin-resistant cells, and may be dependent on the concentration of intracellular chloride (Cf) ions and intracellular pH. The primary aim of this study was to describe the modifying effects of NHMA (5-N,N hexamethylene; amiloride), a Na+/H+ antiport inhibitor, and/or SITS (4-acetamido-4\u27;isothiocyanostilbene-2,2\u27-disulfonic acid), a HC03-/C1- transport inhibitor, in bicarbonate-containing or bicarbonate-free media on cisplatin (cis-diamminedichloroplatinum(II); CDDP) toxicity between known cisplatin-sensitive (C0S31) and cisplatin-resistant (C0S31/rCDDP) canine osteosarcoma cells. This study has shown that cell survival can be influenced by the inhibition of the Na+-dependent HCO3-/Cl- exchanger using SITS. The addition of SITS increases the intracellular C- concentration in canine osteosarcoma cells cultured in a bicarbonate-containing media. In a bicarbonate-free media, the addition of SITS results in a decrease in the cytotoxic action of cisplatin

In vitro investigation of a terbinafine impregnated subcutaneous implant for veterinary use

A terbinafine impregnated subcutaneous implant was evaluated to determine if drug was released into isotonic saline over the course of 6 months at two different temperatures, 37°C and 4°C. These temperatures were chosen to simulate the nonhibernating (37°C) and hibernating body (4°C) temperatures of little brown bats (Myotis lucifugus). Insectivorous bats of North America, including little brown bats, have been devastated by white nose syndrome, a fungal infection caused by Geomyces destructans. No treatments exist for bats infected with G. destructans. Implants were placed into isotonic saline; samples were collected once per week and analyzed with HPLC to determine terbinafine concentrations. The mean amount of terbinafine released weekly across the 28 weeks was approximately 1.7 μg at 4°C and 4.3 μg at 37°C. Although significant differences in the amount released did occur at some time points, these differences were not consistently greater or less at either of the temperatures. This study showed that terbinafine was released from an impregnated implant over the course of 6 months at concentrations ranging from 0.02 to 0.06 μg/mL depending on temperature, which may be appropriate for little brown bats (Myotis lucifugus) infected with Geomyces destructans, the etiologic agent of white nose syndrome

High-Performance Liquid Chromatography Determination of Meloxicam and Piroxicam with Ultraviolet Detection

A simple accurate and sensitive high-performance liquid chromatographic method for the determination of meloxicam and piroxicam concentrations in small volume plasma samples has been developed. Following a liquid extraction using chloroform, samples were separated by reversed-phase high-performance liquid chromatography on an XBridge C18 column (4.6 × 250 mm) and quantified using ultraviolet detection at 360 nm. The mobile phase was a mixture of water with glacial acetic acid (pH 3.0) and acetonitrile (50 : 50), with a flow rate of 1.0 mL/min. The standard curve ranged from 5 to 10,000 ng/mL for meloxicam in bearded dragon (Pogona vitticeps) plasma and piroxicam in crane (Grus rubicunda) plasma. Intra- and interassay variability for meloxicam and piroxicam were less than 10% and the average recovery was greater than 90% for both drugs. This method was developed in bearded dragon and crane plasma and should be applicable to any species, making it useful for those investigators dealing with small sample volumes, particularly when conducting pharmacokinetics studies which require multiple sampling from the same animal

Determining Terbinafine in Plasma and Saline Using HPLC

A simple, sensitive, and accurate high-performance liquid chromatography (HPLC) method for the determination of terbinafine concentrations in small-volume plasma and saline has been developed. Following a liquid extraction using hexane, samples were separated by reversed-phase HPLC on a Symmetry Shield RP18 (5 µm) 4.6 mm × 100 mm column and quantified using ultraviolet detection at 224 nm. The mobile phase was a mixture of water, phosphoric acid, and triethylamine (pH 3.0), with acetonitrile (65:35, v/v), at a flow rate of 1.1 mL/min. The standard curve ranged from 5 to 1500 ng/mL for parrot plasma and 1 to 25 µg/mL for 0.9% saline. Intra- and inter-assay variability for terbinafine was less than 10% for both matrices, and the average recovery was greater than 90%. This method has been developed in parrot plasma and should be applicable to other species, making it useful to those investigators dealing with small sample volumes, particularly when conducting pharmacokinetic studies that require multiple sampling from the same animal. This method would also be valuable to aquariums that need to determine terbinafine concentrations in salt water

Synthesis of 5,6-Diaminoacenaphthylene by Reduction of Sterically Crowded Nitro Groups with Sodium Dithionite

5,6-Diaminoacenaphthylene was synthesized in four steps from acenaphthene. This seemingly simple molecule provides unique synthetic challenges because it is relatively difficult to reduce the nitro groups and the molecule contains a particularly reactive double bond. It was determined that the only feasible sequence for the synthesis was to nitrate acenaphthene, then brominate, eliminate, and finally selectively reduce. Several reduction methods were attempted before finding one that would completely reduce both nitro groups while leaving the double bond intact

The 100 most eminent psychologists of the 20th century.

A rank-ordered list was constructed that reports the first 99 of the 100 most eminent psychologists of the 20th century. Eminence was measured by scores on 3 quantitative variables and 3 qualitative variables. The quantitative variables were journal citation frequency, introductory psychology textbook citation frequency, and survey response frequency. The qualitative variables were National Academy of Sciences membership, election as American Psychological Association (APA) president or receipt of the APA Distinguished Scientific Contributions Award, and surname used as an eponym. The qualitative variables were quantified and combined with the other 3 quantitative variables to produce a composite score that was then used to construct a rank-ordered list of the most eminent psychologists of the 20th century. The discipline of psychology underwent a remarkable transformation during the 20th cen-tury, a transformation that included a shift away from the European-influenced philosophical psychology of the late 19th century to th

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Ultralight vector dark matter search using data from the KAGRA O3GK run

Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM