Family Exclusion Clauses: Whatever Happened to the Abrogation of Intrafamily Immunity

This Comment addresses the use of family exclusion clauses in automobile and homeowner insurance policies in California. The author argues that, while these provisions are specifically authorized in automobile policies by statute, legislative justification for such exclusions is lacking for homeowner policies. The author argues that family exclusion clauses should be eliminated in both automobile and homeowner policies because the clauses violate well-settled tort principles, as well as public policy. The author urges the California Supreme Court to reconsider its holdings abolishing intrafamily immunity and declare family exclusionary clauses in homeowner policies void as against public policy. The author further urges the California legislature to eliminate specific sections of the insurance code that permit family exclusion clauses in automobile policies

Transition Metal Substitution Effects on Metal-to-Polyoxometalate Charge Transfer

A series of heterobimetallic transition metal substituted polyoxometalates (TMSPs) have been synthesized based on the CoII-centered ligand [CoIIW11O39]10-. The eight complex series, [CoII(MxOHy)W11O39](12-x-y)- (MxOHy = VIVO, CrIII(OH2), MnII(OH2), FeIII(OH2), CoII(OH2), NiII(OH2), CuII(OH2), ZnII(OH2)), of which six are reported for the first time, was synthesized starting from [CoIIIW11O39]9- and studied using spectroscopic, electrochemical, and computational techniques to evaluate the influence of substituted transition metals on the photodynamics of the metal-to-polyoxometalate charge transfer (MPCT) transition. The bimetallic complexes all show higher visible light absorption than the plenary [CoIIW12O40]6- and demonstrate the same MPCT transition as the plenary complex, but have shorter excited state lifetimes (sub-300 ps in aqueous media). The decreased lifetimes are rationalized on the basis of nonradiative relaxation due to coordinating aqua ligands, increased interaction with cations due to increased negative charge, and the energy gap law, with the strongest single factor appearing to be the charge on the anion. The most promising results are from the Cr- and Fe-substituted systems, which retain excited state lifetimes at least 50% of that of [CoIIW12O40]6- while more than tripling the absorbance at 400 nm

Non-invasive biophysical measurement of travelling waves in the insect inner ear

Frequency analysis in the mammalian cochlea depends on the propagation of frequency information in the form of a travelling wave (TW) across tonotopically arranged auditory sensilla. TWs have been directly observed in the basilar papilla of birds and the ears of bush-crickets (Insecta: Orthoptera) and have also been indirectly inferred in the hearing organs of some reptiles and frogs. Existing experimental approaches to measure TW function in tetrapods and bushcrickets are inherently invasive, compromising the fine-scale mechanics of each system. Located in the forelegs, the bushcricket ear exhibits outer, middle and inner components; the inner ear containing tonotopically arranged auditory sensilla within a fluid-filled cavity, and externally protected by the leg cuticle. Here, we report bush-crickets with transparent ear cuticles as potential model species for direct, non-invasive measuring of TWs and tonotopy. Using laser Doppler vibrometry and spectroscopy, we show that increased transmittance of light through the ear cuticle allows for effective non-invasive measurements of TWs and frequency mapping. More transparent cuticles allow several properties of TWs to be precisely recovered and measured in vivo from intact specimens. Our approach provides an innovative, noninvasive alternative to measure the natural motion of the sensillia-bearing surface embedded in the intact inner ear fluid

A novel reagentless glutamate microband biosensor for real-time cell toxicity monitoring

A reagentless glutamate biosensor was applied to the determination of glutamate released from liver hepatocellular carcinoma cells (HepG2) in response to toxic challenge from various concentrations of paracetamol. A screen printed carbon electrode (SPCE) containing the electrocatalyst Meldola's Blue (MB-SPCE) served as the electron mediator for the oxidation of NADH.A mixture of the enzyme glutamate dehydrogenase (GLDH), cofactor nicotinamide adenine dinucleotide (NAD+) and the biopolymer chitosan (CHIT) were drop-coated onto the surface of the transducer (MB-SPCE) in a simple one step fabrication process.The reagentless biosensor was used with amperometry in stirred solution at an applied potential of +0.1 V (vs. Ag/AgCl). All experiments were carried out at the following conditions: pH 7, temperature 37 °C, atmosphere 5% CO2.The linear range of the device was found to be 25–125 μM in phosphate buffer (75 mM, containing 0.05 M NaCl) and 25–150 μM in cell culture medium. The limits of detection (LOD) were found to be 1.2 μM and 4.2 μM based on three times signal to noise, using PBS and culture medium respectively. The sensitivity was calculated to be 106 nA μM−1 cm−2 and 210 nA μM−1 cm−2 in PBS and cell medium respectively. The response time was ∼60 s in an agitated solution.HepG2 cells were exposed to various concentrations of paracetamol (1 mM, 5 mM and 10 mM) in order to investigate the drug-induced release of glutamate into the culture medium in real time. Two toxicity studies were investigated using different methods of exposure and analysis.The first method consisted of a single measurement of the glutamate concentration, using the method of standard addition, after 24 h incubation. The concentrations of glutamate were found to be 52 μM, 93 μM and 177 μM, released on exposure to 1 mM, 5 mM and 10 mM paracetamol respectively.The second method involved the continuous monitoring of glutamate released from HepG2 cells upon exposure to paracetamol over 8 h. The concentrations of glutamate released in the presence of 1 mM, 5 mM and 10 mM paracetamol, increased in proportion to the drug concentration, ie: 16 μM, 28 μM and 62 μM respectively. This result demonstrates the feasibility of using this approach to monitor early metabolic changes after exposure to a model toxic compound

Diquat Derivatives: Highly Active, Two-Dimensional Nonlinear Optical Chromophores with Potential Redox Switchability

In this article, we present a detailed study of structure−activity relationships in diquaternized 2,2′-bipyridyl (diquat) derivatives. Sixteen new chromophores have been synthesized, with variations in the amino electron donor substituents, π-conjugated bridge, and alkyl diquaternizing unit. Our aim is to combine very large, two-dimensional (2D) quadratic nonlinear optical (NLO) responses with reversible redox chemistry. The chromophores have been characterized as their PF_6^− salts by using various techniques including electronic absorption spectroscopy and cyclic voltammetry. Their visible absorption spectra are dominated by intense π → π^* intramolecular charge-transfer (ICT) bands, and all show two reversible diquat-based reductions. First hyperpolarizabilities β have been measured by using hyper-Rayleigh scattering with an 800 nm laser, and Stark spectroscopy of the ICT bands affords estimated static first hyperpolarizabilities β_0. The directly and indirectly derived β values are large and increase with the extent of π-conjugation and electron donor strength. Extending the quaternizing alkyl linkage always increases the ICT energy and decreases the E_(1/2) values for diquat reduction, but a compensating increase in the ICT intensity prevents significant decreases in Stark-based β_0 responses. Nine single-crystal X-ray structures have also been obtained. Time-dependent density functional theory clarifies the molecular electronic/optical properties, and finite field calculations agree with polarized HRS data in that the NLO responses of the disubstituted species are dominated by ‘off-diagonal’ β_(zyy) components. The most significant findings of these studies are: (i) β_0 values as much as 6 times that of the chromophore in the technologically important material (E)-4′-(dimethylamino)-N-methyl-4-stilbazolium tosylate; (ii) reversible electrochemistry that offers potential for redox-switching of optical properties over multiple states; (iii) strongly 2D NLO responses that may be exploited for novel practical applications; (iv) a new polar material, suitable for bulk NLO behavior

Global Transcriptomic Profiling Using Small Volumes of Whole Blood: A Cost-Effective Method for Translational Genomic Biomarker Identification in Small Animals

Blood is an ideal tissue for the identification of novel genomic biomarkers for toxicity or efficacy. However, using blood for transcriptomic profiling presents significant technical challenges due to the transcriptomic changes induced by ex vivo handling and the interference of highly abundant globin mRNA. Most whole blood RNA stabilization and isolation methods also require significant volumes of blood, limiting their effective use in small animal species, such as rodents. To overcome these challenges, a QIAzol-based RNA stabilization and isolation method (QSI) was developed to isolate sufficient amounts of high quality total RNA from 25 to 500 μL of rat whole blood. The method was compared to the standard PAXgene Blood RNA System using blood collected from rats exposed to saline or lipopolysaccharide (LPS). The QSI method yielded an average of 54 ng total RNA per μL of rat whole blood with an average RNA Integrity Number (RIN) of 9, a performance comparable with the standard PAXgene method. Total RNA samples were further processed using the NuGEN Ovation Whole Blood Solution system and cDNA was hybridized to Affymetrix Rat Genome 230 2.0 Arrays. The microarray QC parameters using RNA isolated with the QSI method were within the acceptable range for microarray analysis. The transcriptomic profiles were highly correlated with those using RNA isolated with the PAXgene method and were consistent with expected LPS-induced inflammatory responses. The present study demonstrated that the QSI method coupled with NuGEN Ovation Whole Blood Solution system is cost-effective and particularly suitable for transcriptomic profiling of minimal volumes of whole blood, typical of those obtained with small animal species

Cytokine-associated drug toxicity in human hepatocytes is associated signaling network dysregulation

Refer to Web version on PubMed Central for supplementary material.Idiosyncratic drug hepatotoxicity is a major problem in pharmaceutical development due to poor prediction capability of standard preclinical toxicity assessments and limited knowledge of its underlying mechanisms. Findings in animal models have shown that adverse effects of numerous drugs with idiosyncratic hepatotoxicity in humans can be reproduced in the presence of coincident inflammatory cytokine signaling. Following these observations, we have recently developed an in vitro drug/inflammatory cytokine co-treatment approach that can reproduce clinical drug hepatotoxicity signatures—particularly for idiosyncratic drugs—in cultured primary human hepatocytes. These observations have suggested that drug-induced stresses may interact with cytokine signaling to induce hepatic cytotoxicity, but the hepatocyte signaling mechanisms governing these interactions are poorly understood. Here, we collect high-throughput phosphoprotein signaling and cytotoxicity measurements in cultured hepatocytes, from multiple human donors, treated with combinations of hepatotoxic drugs (e.g. trovafloxacin, clarithromycin) and cytokines (tumor necrosis factor-α, interferon-γ, interleukin-1α, and interleukin-6). We demonstrate, through orthogonal partial least-squares regression (OPLSR) modeling of these signal-response data, that drug/cytokine hepatic cytotoxicity is integratively controlled by four key signaling pathways: Akt, p70 S6 kinase, MEK–ERK, and p38–HSP27. This modeling predicted, and experimental studies confirmed, that the MEK–ERK and p38–HSP27 pathways contribute pro-death signaling influences in drug/cytokine hepatic cytotoxicity synergy. Further, our four-pathway OPLSR model produced successful prediction of drug/cytokine hepatic cytotoxicities across different human donors, even though signaling and cytotoxicity responses were both highly donor-specific. Our findings highlight the critical role of kinase signaling in drug/cytokine hepatic cytotoxicity synergies and reveal that hepatic cytotoxicity responses are governed by multi-pathway signaling network balance.Pfizer Inc.Institute for Collaborative BiotechnologiesMIT Center for Cell Decision ProcessesNational Institute of Mental Health (U.S.) (grant P50-GM68762)Massachusetts Institute of Technology. Biotechnology Process Engineering CenterMassachusetts Institute of Technology. Center for Environmental Health SciencesNational Institute of Mental Health (U.S.) (grant U19ES011399)Whitaker Foundatio