Development of a Physiologically Based Pharmacokinetic Model for Nitrofurantoin in Rabbits, Rats, and Humans

Nitrofurantoin (NFT) is a commonly used antibiotic for the treatment of urinary tract infections that can cause liver toxicity. Despite reports of hepatic adverse events associated with NFT exposure, there is still limited understanding of the interplay between NFT exposure, its disposition, and the risk of developing liver toxicity. In this study, we aim to develop a physiologically based pharmacokinetic (PBPK) model for NFT in three different species (rabbits, rats, and humans) that can be used as a standard tool for predicting drug-induced liver injury (DILI). We created several versions of the PBPK model using previously published kinetics data from rabbits, and integrated enterohepatic recirculation (EHR) using rat data. Our model showed that active tubular secretion and reabsorption in the kidney are critical in explaining the non-linear renal clearance and urine kinetics of NFT. We subsequently extrapolated the PBPK model to humans. Adapting the physiology to humans led to predictions consistent with human kinetics data, considering a low amount of NFT to be excreted into bile. Model simulations predicted that the liver of individuals with a moderate-to-severe glomerular filtration rate (GFR) is exposed to two-to-three-fold higher concentrations of NFT than individuals with a normal GFR, which coincided with a substantial reduction in the NFT urinary concentration. In conclusion, people with renal insufficiency may be at a higher risk of developing DILI due to NFT exposure, while at the same time having a suboptimal therapeutic effect with a high risk of drug resistance. Our PBPK model can in the future be used to predict NFT kinetics in individual patients on the basis of characteristics like age and GFR.

Development of a Rat Physiologically Based Kinetic Model (PBK) for three Organophosphate Flame Retardants (TDCIPP, TCIPP, TCEP)

Tris(1,3-dichloro-2-propyl) phosphate (TDCIPP), Tris (1-chloro-2-propyl) phosphate (TCIPP) and tris (2-chloroethyl) phosphate (TCEP) are three widely used organophosphate flame retardants (OPFRs) being frequently detected in human body fluids. Although OPFRs are being detected in human beings, the toxicological effects of their exposure are not clearly understood due to limited data. For this, a physiologically based kinetic model (PBK) was developed in MCSIM integrated with R studio and validated in rats to understand the toxicokinetics of OPFRs for the first time. The model required the enterohepatic recirculation (EHR) mechanism which was included to explain the non-linear data. Model parameters were optimized using the Bayesian framework (Markov Chain Monte Carlo) along with a visual fitting to explain toxicokinetic data. Goodness-of-fit was calculated to evaluate model predictability power in Rstudio. The model can appropriately predict the concentration of OPFRs in several organs like plasma, urine, kidney, etc. within 1-2-fold of experimental data. Slow elimination of OPFRs was observed from adipose tissue and brain at late time points, showing their potential to accumulate upon daily exposure. The use of PBK was demonstrated by reconstructing the oral exposure equivalent to the in-vitro toxic dose to support neurotoxic risk assessment. This version of PBK can be extrapolated to human for toxicological risk assessment. Nonetheless, further investigation is required to understand whether these chemicals follow similar kinetics in humans, which could lead to a greater risk to human health. CODE AVAILABILITY: The model will be available to access through Rshiny using GIThub soon, InSilicoVida/Flame-Retardant-PBPK-Model: It contains organophosphate flame retardant (OPFRs) PBK for TDCIPP, TCIPP and TCEP (github.com).

Unravelling sex-specific BPA toxicokinetics in children using a pediatric PBPK model

Bisphenol A (BPA) is a widely known endocrine disruptor (ED) found in many children's products such as toys, feeding utensils, and teething rings. Recent epidemiology association studies have shown postnatal BPA exposure resulted in developing various diseases such as diabetes, obesity, and neurodegeneration, etc., later in their lives. However, little is known about its sex-specific metabolism and consequently internal exposure. The aim of this study was to develop a sex-specific pediatric physiologically based pharmacokinetic model (PBPK) for BPA to compare their toxicokinetic differences. First, the published adult PBPK model was re-validated, and then this model was extended by interpolation to incorporate pediatric sex specific physiological and biochemical parameters. We used both the classical body weight and ontogeny-based scaling approach to interpolate the metabolic process. Then, the pharmacokinetic attributes of the models using the two-scaling approach mentioned above were compared with adult model. Further, a sex-specific PBPK model with an ontogeny scaling approach was preferred to evaluate the pharmacokinetic differences. Moreover, this model was used to reconstruct the BPA exposure from two cohorts (Helix and PBAT Cohort) from 7 EU countries. The half-life of BPA was found to be almost the same in boys and girls at the same exposure levels. Our model estimated BPA children's exposure to be about 1500 times higher than the tolerable daily intake (TDI) recently set by European Food Safety Authority (EFSA) i.e., 0.04 ng/kg BW/day. The model demonstrated feasibility of extending the adult PBPK to sex-specific pediatric, thus investigate a gender-specific health risk assessment.

Chlorpyrifos, permethrin and cyfluthrin effect on cell survival, permeability, and tight junction in an in-vitro model of the human blood-brain barrier (BBB)

The blood-brain barrier (BBB) is a structural and functional interface between the plasma and the human brain. Predictive BBB in-vitro models like immortalized human capillary microvascular endothelial cells (HCMEC/D3) can be used to explore the BBB disruption potential of daily exposed chemicals. The present study was focused on investigating the human BBB permeation potential of one organophosphate pesticide, chlorpyrifos (CPF), and two pyrethroids, permethrin (PMT) and cyfluthrin (CFT). HCMEC/D3 cells were exposed to the chemical and the time-dependent pass across BBB along with permeation coefficient (Papp) was calculated. Transendothelial electrical resistance (TEER) was measured for the cells to check the monolayer formation and later to check the reduction in integrity after chemical exposure. Real time PCR was conducted to investigate the effect of chemicals on the expression BBB´s tight and adherens junction proteins. Calculated Papp value for three chemicals was in the following order: CPF>CFT>PMT, where CPF showed the highest permeation coefficient. TEER calculation showed that the integrity decreased after CPF exposure which was in concordance with Papp value whereas for other chemicals, no change in TEER after exposure was observed. In addition, the transwell study showed a higher efflux ratio (ER) (>2) of CFT indicating that CFT could be a substrate for active transport. For CPF and PMT, ER was less than 2, so no active transport seems to be involved. The evaluation of the mRNA expression analysis revealed a statistically significant decrease in Occludin (OCLN) gene expression for CPF, VE-Cadherin (CDH5) for PMT and Zonula Occludens (ZO1) expression for CFT. Our study showed that CPF has the highest potential for inducing cell death, higher permeation, and capability to induce BBB dysfunction than among the above-mentioned chemicals. Additionally, the results of the permeation study could be useful to build a human PBPK model using in vitro-to-in vivo extrapolation approach.

Predictors of increased mortality in untreated moderate aortic stenosis

Background

The natural history of native valvular moderate aortic stenosis (AS) is poorly understood.

Purpose

To examine the prognosis of patients with native valvular moderate AS, and identify high risk-features associated with increased mortality.

Methods

Natural language processing of electronic health records in the claims-linked Optum® database (2011–2018) from over 200 hospitals and 7000 clinics in the United States identified severity of AS (mild/moderate/severe) from echocardiograms and physician notes of patients more than 65 years old. Our cohort included 30,204 patients (3594 with mild, 9938 with moderate, and 16672 with severe AS). We used competing risk Kaplan-Meier analysis to compare 5-year mortality (obtained from the Social Security Death Masterfile) between the different AS severity groups adjusted for demographics and comorbidities, censoring for aortic valve replacement. The relationship between AS severity and survival was examined during median 1049 days (interquartile range: 597 to 1652 days) of follow-up. We performed Fine-Gray modeling to examine risk factors associated with long-term mortality in patients with moderate AS.

Results

A higher proportion of comorbidities like atrial fibrillation, diabetes, and coronary artery disease were observed with increasing severity of AS (Figure 1). After adjustment, compared with mild AS (5-year mortality: 31.6%), patients with untreated moderate (5-year mortality: 40.0%, HR 1.34, 95% CI 1.25 – 1.44) and untreated severe AS (5-year mortality: 51.1%, HR 1.88, 95% CI 1.75– 2.01) have increasing risk of long-term mortality (Figure 2). Significant predictors of 5-year mortality in patients with moderate AS include older age (HR 1.38, 95% CI 1.29 –1.47), male sex (HR 1.21, 95% CI 1.15 – 1.27), heart failure (HR 1.37, 95% CI 1.29 – 1.44), coronary artery disease (HR 1.20, 95% CI 1.13 – 1.27), and atrial fibrillation (HR 1.08, 95% CI 1.02 – 1.14). In a subcohort of 5189 patients for whom left ventricular ejection fraction (LVEF) information was available, reduced LVEF was associated with worse long-term mortality (LVEF<40%: HR 1.17, 95% CI 1.05 –1.31; LVEF 40–50%: HR 1.08, 95% CI 0.97 –1.20).

Conclusion

Our findings suggest that moderate AS is associated with poor long-term survival with higher risk associated with LVEF <40%, and comorbidities including heart failure, coronary artery disease and atrial fibrillation. Whether patients with moderate AS, particularly with high-risk features, benefit from treatment remains unknown.

Funding Acknowledgement

Type of funding sources: None. Baseline CharacteristicsAdjusted KM curves with Competing Risk

Risk Assessment of Perfluorooctane Sulfonate (PFOS) using Dynamic Age Dependent Physiologically based Pharmacokinetic Model (PBPK) across Human Lifetime

The widespread use of Perfluorooctane sulfonate (PFOS) in everyday life, its long half-life, and the lipophilicity that makes it easily accumulate in the body, raises the question of its safe exposure among different population groups. There are currently enough epidemiological studies showing evidence of PFOS exposure and its associated adverse effects on humans. Moreover, it is already known that physiological changes along with age e.g. organ volume, renal blood flow, cardiac output and albumin concentrations affect chemicals body burden. Human biomonitoring cohort studies have reported PFOS concentrations in blood and autopsy tissue data with PFOS present in sensitive organs across all human lifespan. However, to interpret such biomonitoring data in the context of chemical risk assessment, it is necessary to have a mechanistic framework that explains show the physiological changes across age affects the concentration of chemical inside different tissues of the human body. PBPK model is widely and successfully used in the field of risk assessment. The objective of this manuscript is to develop a dynamic age-dependent PBPK model as an extension of the previously published adult PFOS model and utilize this model to predict and compare the PFOS tissue distribution and plasma concentration across different age groups. Different cohort study data were used for exposure dose reconstruction and evaluation of time-dependent concentration in sensitive organs. Predicted plasma concentration followed trends observed in biomonitoring data and model predictions showed the increased disposition of PFOS in the geriatric population. PFOS model is sensitive to parameters governing renal resorption and elimination across all ages, which is related to PFOS half-life in humans. This model provides an effective framework for improving the quantitative risk assessment of PFOS throughout the human lifetime, particularly in susceptible age groups. The dynamic age-dependent PBPK model provides a step forward for developing such kind of dynamic model for other perfluoroalkyl substances.

ROS networks: designs, aging, Parkinson's disease and precision therapies

How the network around ROS protects against oxidative stress and Parkinson's disease (PD), and how processes at the minutes timescale cause disease and aging after decades, remains enigmatic. Challenging whether the ROS network is as complex as it seems, we built a fairly comprehensive version thereof which we disentangled into a hierarchy of only five simpler subnetworks each delivering one type of robustness. The comprehensive dynamic model described in vitro data sets from two independent laboratories. Notwithstanding its five-fold robustness, it exhibited a relatively sudden breakdown, after some 80 years of virtually steady performance: it predicted aging. PD-related conditions such as lack of DJ-1 protein or increased α-synuclein accelerated the collapse, while antioxidants or caffeine retarded it. Introducing a new concept (aging-time-control coefficient), we found that as many as 25 out of 57 molecular processes controlled aging. We identified new targets for "life-extending interventions": mitochondrial synthesis, KEAP1 degradation, and p62 metabolism.

Development and evaluation of a harmonized whole body physiologically based pharmacokinetic (PBPK) model for flutamide in rats and its extrapolation to humans

By their definition, inadvertent exposure to endocrine disrupting compounds (EDCs) intervenes with the endocrine signalling system, even at low dose. On the one hand, some EDCs are used as important pharmaceutical drugs that one would not want to dismiss. On the other hand, these pharmaceutical drugs are having off-target effects and increasingly significant exposure to the general population with unwanted health implications. Flutamide, one of the top pharmaceutical products marketed all over the world for the treatment of prostate cancer, is also a pollutant. Its therapeutic action mainly depends on targeting the androgen receptors and inhibiting the androgen action that is essential for growth and survival of prostate tissue. Currently flutamide is of concern with respect to its categorization as an endocrine disruptor. In this work we have developed a physiologically based pharmacokinetic (PBPK) model of flutamide that could serve as a standard tool for its human risk assessment. First we built the model for rat (where many parameters have been measured). The rat PBPK model was extrapolated to human where the re-parameterization involved human-specific physiology, metabolic kinetics derived from in-vitro studies, and the partition coefficient same as the rat model. We have harmonized the model by integrating different sets of in-vitro, in-vivo and physiological data into a PBPK model. Then the model was used to simulate different exposure scenarios and the results were compared against the observed data. Both uncertainty and sensitivity analysis was done. Since this new whole-body PBPK model can predict flutamide concentrations not only in plasma but also in various organs, the model may have clinical applications in efficacy and safety assessment of flutamide. The model can also be used for reverse dosimetry in the context of interpreting the available biomonitoring data to estimate the degree to which the population is currently being exposed, and a tool for the pharmaceutical companies to validate the estimated Permitted Daily Exposure (PDE) for flutamide.

Prenatal exposure to PFOS and PFOA in a pregnant women cohort of Catalonia, Spain

This study was aimed at assessing the prenatal exposure to perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) in a cohort of pregnant women living in Reus (Tarragona County, Catalonia, Spain). These chemicals were biomonitored in maternal plasma during the first trimester of pregnancy, at delivery, and in cord blood. The dietary exposure of PFOS and PFOA was estimated by using questionnaires of food frequency and water intake, as well as data on food levels previously reported in the same area. In addition, the exposure through air inhalation and indoor dust ingestion was also calculated. Finally, a physiologically-based pharmacokinetic (PBPK) model was applied in order to establish the prenatal exposure of the fetus/child and to adjust exposure assessment vs. biomonitoring results. Probabilistic calculations of fetal exposure were performed by forward internal dosimetry and Monte-Carlo simulation. Mean plasma levels of PFOA were 0.45, 0.13 and 0.12 ng/mL at the first trimester, at delivery and in cord plasma, while those of PFOS were 2.93, 2.21, and 1.17 ng/mL, respectively. Traces of PFOS were found in all samples in the trimester and at delivery, and almost in all cord blood samples. Transplacental transfers of PFOS and PFOA were estimated to be around 70% and 60%, respectively. A temporal decrease trend in plasma levels of PFOS and PFOA was noticed, when comparing current values with data obtained 10 years ago in the same area. In agreement with many other studies, dietary intake was the main route of exposure to PFOS and PFOA in our cohort of pregnant women. It is an important issue to establish the exposure in critical windows periods such as fetal development to perfluoroalkylated substances, but also to other endocrine disrupting chemicals.

Risperidone effects on heterochromatin: the role of kinase signaling

Epigenetic effects of anti-psychotic medications are poorly understood. We have appropriated a model whereby heterochromatin is established through 24- or 48-h lipopolysaccharide (LPS) treatment, and tested the epigenetic effects of risperidone along the adenylyl cyclase/protein kinase A (AC/PKA) pathway in human liposarcoma cells that express the LPS-sensitive Toll-like receptor (TLR)-4. Human SW872 cells were cultured with LPS and mRNA expression levels and epigenetic modifications of dimethylated lysine 9 of histone 2 (H3K9me2), geterochromatin protein 1γ (HP1γ) and phospho-H3S10 at promoters of interleukin (IL)-6, tumor necrosis factor (TNF)-α and IL1β were measured. Pharmacological manipulation of the AC/PKA pathway was achieved through treatment with a PKA inhibitor (H89), mitogen- and stress-activated kinase 1 (MSK1) inhibitor (SB-747651A) or forskolin. Twenty-four and 48-h LPS treatment establishes heterochromatin at selected promoters, corresponding to decreased mRNA expression. Concurrent risperidone treatment with LPS treatment can both 'block' and 'reverse' heterochromatin formation. Forskolin treatment resulted in a similar disassembling effect on heterochromatin. Conversely, inhibition of PKA by H89 or MSK1 both blocked 'normalizing' effects of risperidone on LPS-induced heterochromatin. Our results demonstrate that risperidone can disassemble heterochromatin, exerting this effect along the G-protein/AC/PKA pathway. This approach can also be utilized to investigate functional outcomes of single or combined pharmacological treatments on chromatin assemblies in human cells.

The development of a pregnancy PBPK Model for Bisphenol A and its evaluation with the available biomonitoring data

Recent studies suggest universal fetal exposure to Bisphenol A (BPA) and its association with the adverse birth outcomes. Estimation of the fetal plasma BPA concentration from the maternal plasma BPA would be highly useful to predict its associated risk to this specific population. The objective of current work is to develop a pregnancy-physiologically based pharmacokinetic (P-PBPK) model to predict the toxicokinetic profile of BPA in the fetus during gestational growth, and to evaluate the developed model using biomonitoring data obtained from different pregnancy cohort studies. To achieve this objective, first, the adult PBPK model was developed and validated with the human BPA toxicokinetic data. This validated human PBPK model was extended to develop a P-PBPK model, which included the physiological changes during pregnancy and the fetus sub-model. The developed model would be able to predict the BPA pharmacokinetics (PKs) in both mother and fetus. Transplacental BPA kinetics parameters for this study were taken from the previous pregnant mice study. Both oral and dermal exposure routes were included into the model to simulate total BPA internal exposure. The impact of conjugation and deconjugation of the BPA and its metabolites on fetal PKs was investigated. The developed P-PBPK model was evaluated against the observed BPA concentrations in cord blood, fetus liver and amniotic fluid considering maternal blood concentration as an exposure source. A range of maternal exposure dose for the oral and dermal routes was estimated, so that simulation concentration matched the observed highest and lowest mother plasma concentration in different cohorts' studies. The developed model could be used to address the concerns regarding possible adverse health effects in the fetus being exposed to BPA and might be useful in identifying critical windows of exposure during pregnancy.

Review on crosstalk and common mechanisms of endocrine disruptors: Scaffolding to improve PBPK/PD model of EDC mixture

Endocrine disruptor compounds (EDCs) are environment chemicals that cause harmful effects through multiple mechanisms, interfering with hormone system resulting in alteration of homeostasis, reproduction and developmental effect. Many of these EDCs have concurrent exposure with crosstalk and common mechanisms which may lead to dynamic interactions. To carry out risk assessment of EDCs' mixture, it is important to know the detailed toxic pathway, crosstalk of receptor and other factors like critical window of exposure. In this review, we summarize the major mechanism of actions of EDCs with the different/same target organs interfering with the same/different class of hormone by altering their synthesis, metabolism, binding and cellular action. To show the impact of EDCs on life stage development, a case study on female fertility affecting germ cell is illustrated. Based on this summarized discussion, major groups of EDCs are classified based on their target organ, mode of action and potential risk. Finally, a conceptual model of pharmacodynamic interaction is proposed to integrate the crosstalk and common mechanisms that modulate estrogen into the predictive mixture dosimetry model with dynamic interaction of mixture. This review will provide new insight for EDCs' risk assessment and can be used to develop next generation PBPK/PD models for EDCs' mixture analysis.

Nonlinear laser pulse response in a crystalline lens

The propagation characteristics of a spatial Gaussian laser pulse have been studied inside a gradient-index structured crystalline lens with constant-density plasma generated by the laser-tissue interaction. The propagation of the laser pulse is affected by the nonlinearities introduced by the generated plasma inside the crystalline lens. Owing to the movement of plasma species from a higher- to a lower-temperature region, an increase in the refractive index occurs that causes the focusing of the laser pulse. In this study, extended paraxial approximation has been applied to take into account the evolution of the radial profile of the Gaussian laser pulse. To examine the propagation characteristics, variation of the beam width parameter has been observed as a function of the laser power and initial beam radius. The cavitation bubble formation, which plays an important role in the restoration of the elasticity of the crystalline lens, has been investigated.

Self, Voices and Embodiment: A Phenomenological Analysis

OBJECTIVE

The primary aim of this study was to examine first-person phenomenological descriptions of the relationship between the self and Auditory Verbal Hallucinations (AVHs). Complex AVHs are frequently described as entities with clear interpersonal characteristics. Strikingly, investigations of first-person (subjective) descriptions of the phenomenology of the relationship are virtually absent from the literature.

METHOD

Twenty participants with psychosis and actively experiencing AVHs were recruited from the University of Illinois at Chicago. A mixed-methods design involving qualitative and quantitative components was utilized. Following a priority-sequence model of complementarity, quantitative analyses were used to test elements of emergent qualitative themes.

RESULTS

The qualitative analysis identified three foundational constructs in the relationship between self and voices: 'understanding of origin,' 'distinct interpersonal identities,' and 'locus of control.' Quantitative analyses further supported identified links of these constructs. Subjects experienced their AVHs as having identities distinct from self and actively engaged with their AVHs experienced a greater sense of autonomy and control over AVHs.

DISCUSSION

Given the clinical importance of AVHs and emerging strategies targeting the relationship between the hearer and voices, our findings highlight the importance of these relational constructs in improvement and innovation of clinical interventions. Our analyses also underscore the value of detailed voice assessments such as those provided by the Maastricht Interview are needed in the evaluation process. Subjects narratives shows that the relational phenomena between hearer and AVH(s) is dynamic, and can be influenced and changed through the hearers' engagement, conversation, and negotiation with their voices.

Physiological, anatomical and transcriptional alterations in a rice mutant leading to enhanced water stress tolerance

Water stress is one of the most severe constraints to crop productivity. Plants display a variety of physiological and biochemical responses both at the cellular and whole organism level upon sensing water stress. Leaf rolling, stomatal closure, deeper root penetration, higher relative water content (RWC) and better osmotic adjustment are some of the mechanisms that plants employ to overcome water stress. In the current study, we report a mutant, enhanced water stress tolerant1 (ewst1) with enhanced water stress tolerance, identified from the ethyl methanesulfonate-induced mutant population of rice variety Nagina22 by field screening followed by withdrawal of irrigation in pots and hydroponics (PEG 6000). Though ewst1 was morphologically similar to the wild type (WT) for 35 of the 38 morphological descriptors (except chalky endosperm/expression of white core, decorticated grain colour and grain weight), it showed enhanced germination in polyethylene glycol-infused medium. It exhibited increase in maximum root length without any significant changes in its root weight, root volume and total root number on crown when compared with the WT under stress in PVC tube experiment. It also showed better performance for various physiological parameters such as RWC, cell membrane stability and chlorophyll concentration upon water stress in a pot experiment. Root anatomy and stomatal microscopic studies revealed changes in the number of xylem and phloem cells, size of central meta-xylem and number of closed stomata in ewst1. Comparative genome-wide transcriptome analysis identified genes related to exocytosis, secondary metabolites, tryptophan biosynthesis, protein phosphorylation and other signalling pathways to be playing a role in enhanced response to water stress in ewst1. The possible involvement of a candidate gene with respect to the observed morpho-physiological and transcriptional changes and its role in stress tolerance are discussed. The mutant identified and characterized in this study will be useful for further dissection of water stress tolerance in rice.

Effect of multiphoton ionization on performance of crystalline lens

This Letter presents a model for propagation of a laser pulse in a human crystalline lens. The model contains a transverse beam diffraction effect, laser-induced optical breakdown for the creation of plasma via a multiphoton ionization process, and the gradient index (GRIN) structure. Plasma introduces the nonlinearity in the crystalline lens which affects the propagation of the beam. The multiphoton ionization process generates plasma that changes the refractive index and hence leads to the defocusing of the laser beam. The Letter also points out the relevance of the present investigation to cavitation bubble formation for restoring the elasticity of the eyes.

Optical forces and torques on realistic plasmonic nanostructures: a surface integral approach

We develop a novel formalism to calculate the optical forces and torques on complex and realistic nanostructures by combining the surface integral equation (SIE) technique with Maxwell's stress tensor. The optical force is calculated directly on the scatterer surface from the currents obtained from the SIE, which does not require an additional surface to evaluate Maxwell's stress tensor; this is especially useful for intricate geometries such as plasmonic antennas. SIE enables direct evaluation of forces from the surface currents very efficiently and accurately for complex systems. As a proof of concept, we establish the accuracy of the model by comparing the results with the calculations from the Mie theory. The flexibility of the method is demonstrated by simulating a realistic plasmonic system with intricate geometry.

Toward the identification of peripheral epigenetic biomarkers of schizophrenia

Schizophrenia (SZ) is a heritable, nonmendelian, neurodevelopmental disorder in which epigenetic dysregulation of the brain genome plays a fundamental role in mediating the clinical manifestations and course of the disease. The authors recently reported that two enzymes that belong to the dynamic DNA methylation/demethylation network-DNMT (DNA methyltransferase) and TET (ten-eleven translocase; 5-hydroxycytosine translocator)-are abnormally increased in corticolimbic structures of SZ postmortem brain, suggesting a causal relationship between clinical manifestations of SZ and changes in DNA methylation and in the expression of SZ candidate genes (e.g., brain-derived neurotrophic factor [BDNF], glucocorticoid receptor [GCR], glutamic acid decarboxylase 67 [GAD67], reelin). Because the clinical manifestations of SZ typically begin with a prodrome followed by a first episode in adolescence with subsequent deterioration, it is obvious that the natural history of this disease cannot be studied only in postmortem brain. Hence, the focus is currently shifting towards the feasibility of studying epigenetic molecular signatures of SZ in blood cells. Initial studies show a significant enrichment of epigenetic changes in lymphocytes in gene networks directly relevant to psychiatric disorders. Furthermore, the expression of DNA-methylating/demethylating enzymes and SZ candidate genes such as BDNF and GCR are altered in the same direction in both brain and blood lymphocytes. The coincidence of these changes in lymphocytes and brain supports the hypothesis that common environmental or genetic risk factors are operative in altering the epigenetic components involved in orchestrating transcription of specific genes in brain and peripheral tissues. The identification of DNA methylation signatures for SZ in peripheral blood cells of subjects with genetic and clinical high risk would clearly have potential for the diagnosis of SZ early in its course and would be invaluable for initiating early intervention and individualized treatment plans.

Association of polymorphism in the prolactin promoter and egg quality traits in laying hens

Single strand conformation polymorphism analysis and DNA sequencing was performed in White Leghorn hens to explore the polymorphisms present in the promoter of the prolactin gene. The effects of different genotypes on egg production and quality traits were determined, and expression of the prolactin gene in different genotypes was quantified by real time-PCR. Five genotypes and four alleles at each of two Fragments of the promoter were found, of which the FG genotype in Fragment 1 and the PQ genotype in Fragment 2 were the most predominant genotypes. The genotypes of Fragment 1 had significant effects (P < 0·05) on Haugh unit, albumen weight, albumen percentage and shell percentage at 40 weeks of age; egg weight and yolk index at 52 weeks of age; and egg weight at 64 weeks of age. Prolactin expression in the genotypes of Fragment 1 differed significantly and GH genotyped birds had the highest level of expression. The genotypes of Fragment 2 did not show any significant differences of expression. It was concluded that the prolactin gene promoter was highly polymorphic, and had significant effects on egg quality traits in White Leghorn hens.

Heterochromatin as an incubator for pathology and treatment non-response: implication for neuropsychiatric illness

Heterochromatin is a higher order assembly that is characterized by a genome-wide distribution, gene-repression, durability and potential to spread. In this light, it is an appealing mechanism to interpret the neurobiology of complex brain disorders such as schizophrenia where downregulation of expression appears to be the norm. H3K9 methylation (H3K9me) can initiate the seeding of a heterochromatin assembly on an inactive or poorly coordinated promoter as a consequence of a decline in transactivators either from disuse or from misuse. H3K9me can extend its influence by spatial spreading through the mechanism of recursively recruiting adapters, such as heterochromatin protein 1 (HP1) homodimers. HP1 itself serves as a platform for other repressive proteins such as DNA methyltransferases. In full color, heterochromatin can occupy genome-wide gene networks, tissue specific ontologies and even rearrange the nuclear architecture. Heterochromatin in the brain is modified by small molecule pharmacology and serves a physiological role in the functioning of dopamine neurons and the construction of memory. From a therapeutic perspective, the durable nature of heterochromatin implies that it may require disassembly before the full genomic-potential of standard pharmacotherapies is achieved, especially in treatment resistant patients.

Identification of haplotypes in promoter of prolactin gene and their effect on egg production and quality traits in layer chicken

Expression of prolactin hormone is a crucial event in regulating egg production in chickens for which promoter plays the vital role in expressing the prolactin gene. The objective of the present study was to identify haplotypes in the prolactin promoter and their effects on egg production and egg quality traits in White Leghorn chicken. Single stranded conformation polymorphism followed by sequencing was conducted to explore polymorphism at 561 bp promoter of prolactin gene. The effect of haplotype combinations on egg production and quality traits were estimated following general linear model technique. The expression of prolactin by different haplogroups was quantified by qPCR. Total 28 haplotypes were found in White Leghorn chicken of which h1 haplotype possessed the highest frequency of 0.46 and h8, h14, h16, h25, h26, and h28 haplotypes had the lowest frequency (0.1%). The egg production up to 52 and 64 weeks of age were found to be significantly (p < 0.05) associated with haplotype combinations where the highest 52-w (52 weeks) egg production was found in animals with h1/h22 combination and the lowest production was observed in the birds with h1/h2 haplogroup. The haplotype combinations had the significant effect (p < 0.05) on Haugh Unit, yolk index and albumen weight at 40 weeks of age; Haugh Unit and albumen weight at 52 weeks of age and Haugh unit, yolk weight and yolk percentage at 64 weeks of age. The prolactin expression in h1/h22 birds was found to be the lowest and in h1/h5 birds to be the highest. The prolactin expression showed significant effect on 52-w egg production and albumin weight at 52 weeks age. In conclusion, it may be stated that the prolactin promoter was highly polymorphic and had the significant association with egg production and quality traits in White Leghorn chicken.

Genetic analysis of juvenile growth and carcass traits in a full diallel mating in selected colored broiler lines

The juvenile growth and carcass traits were evaluated in a 4 × 4 full diallel crossing involving four colored broiler chicken lines viz., Naked neck (NN), Dwarf, Punjab Broiler-1 (PB-1), and Punjab Broiler-2 to study the performance and crossbreeding parameters. The data on 2,280 chicks were analyzed using least squares techniques to assess the effect of genetic group, and the significant traits were further analyzed for crossbreeding parameters. Genetic group had significant influence on the body weights and carcass traits. The cross of PB-1 × NN recorded significantly (p ≤ 0.05) higher body weight at 6 weeks of age. The data revealed that general combining ability (GCA), specific combining ability (SCA), maternal ability (MA), sex-linked effect (SE), and purebred effects significantly influenced the growth and carcass traits in the broiler crosses. The crossbred PB-1 × NN showed positive heterosis for growth as well as carcass traits. The results suggest that GCA, SCA, SE, and MA are important in the inheritance of the body weights and carcass traits indicating the presence of both additive and nonadditive genetic variation along with reciprocal effects. Therefore, pure line selection along with development of specialized sire and dam lines followed by crossing will improve the growth performance and benefit the poultry farmers. It is concluded that PB-1 as a male line and NN as a female line performed significantly higher, therefore, may be used for improving the performance of colored broilers.

Associations between novel polymorphisms at the 5'-UTR region of the prolactin gene and egg production and quality in chickens

The objective was to characterize polymorphisms at the 5'-UTR region of the prolactin gene, and determine their association with egg production and egg quality traits in White Leghorn chickens. The study was conducted on four strains of White Leghorn chickens, namely IWH, IWI, IWK, and layer control. Overall, there were three alleles (designated A, B, and C) and five genotypes, with genotypic frequencies of 0.09, 0.75, 0.07, 0.02, and 0.07 for AA, AB, AC, BB, and BC, respectively. There were significant differences among genotypes for egg production up to 52 and 64 wk of age, with maximal egg yields for genotypes AA and AC (144.5 ± 5.06 and 143.2 ± 4.67 eggs, respectively). Furthermore, there were significant differences among genotypes for egg quality traits, including egg weight and Haugh unit at 40 wk of age, Haugh unit at 52 wk, and yolk color index and Haugh unit at 64 wk. Birds with AA or AC genotypes had the best egg quality traits. On the contrary, these genotypes had the lowest prolactin expression, whereas this expression was highest in birds with the BB genotype. In conclusion, polymorphisms at the 5'-UTR of prolactin gene were significantly associated with egg production and egg quality traits in White Leghorn chickens.

Performance and bone mineralisation in broiler chicks fed on diets with different concentrations of cholecalciferol at a constant ratio of calcium to non-phytate phosphorus

1. An experiment was conducted with broiler female chicks (720) to study the effects of graded concentrations (75, 15, 225 or 30 microg/kg) of cholecalciferol (CC) in diets containing varying levels of calcium (Ca) and non-phytate phosphorus (NPP) at a 2:1 ratio (4:2, 5:25, 6:3 or 7:35 g/kg, respectively), on the performance (2-35 d of age), bone mineralisation and mineral (Ca, P, Mn, Fe, Cu) concentration in excreta. 2. Body weight gain, food intake, tibia density and tibia ash increased, and leg abnormality score decreased with dietary increase of CC from 75 to 30 microg at 4 g Ca and 2 g NPP. However, this improvement was not comparable with the birds receiving the highest concentrations of CC, Ca and NPP (30 microg, 7 g and 3.5 g, respectively/kg diet). 3. Significant improvements in the majority of parameters noted with increasing CC up to 225 microg at 5 g Ca and 25 g NPP/kg, which was comparable to those fed the highest levels of CC, Ca and NPP. 4. Concentrations of Ca, P, Mn, Fe and Cu in excreta decreased significantly with increasing CC at all Ca:NPP ratios tested. 5. The predicted requirement of CC for most of the parameters ranged between 1625 and 25 microg/kg diet at 5 g Ca and 25 g NPP. 6. Considering the performance, bone mineralisation, and mineral concentration in excreta, it can be concluded that Ca and NPP levels in broiler diet could be reduced to 5 and 25 g, respectively, while maintaining CC at 25 microg/kg.

No scalpel vasectomy advocacy and community mobilisation--a personal experience

The so called myths and taboos among the people of India are obstactes controlling population explosion and thereby the nation is being handicapped with economic development. To propagate awareness and information, the NSV Resource Center took up organising mega camps for the acceptance of NSV as the method of family planning and male participation. The awareness material has been developed to bring forth total sociocultural transformation through development of intense desire, strong determination, effective management and inclusion of a zeal of perpetual efforts both among the promoters and acceptors. The information modules have been developed to suit the requirements of various vehicles through which the message has to be spread. Awareness messages are generated through the inputs from sociocultural, economic, ethical, hygienic and administrative acumen. The materials prepared are disseminated through display hoardings, wall writings, distribution of pamphlets, audiovisual clips, face to face counselling, etc. Communication technology serves mobilising and educating people, especially rural populace. Some steps are suggested to reach remotest villages which are elaborated. Counselling is an essential part of motivation to the client. During the last 5 years a significant surge has been noticed in terms of access to new communication technologies. This may be employed to successfully implement the family planning programme.

The mycotoxin fumonisin B1transiently activates nuclear factor-κB, tumor necrosis factor α and caspase 3 via protein kinase Cα-dependent pathway in porcine renal epithelial cells

Fumonisin B1 (FB1) is a toxic mycotoxin produced by Fusarium verticillioides, predominantly present in corn. The principal biochemical responses of FB1 involve disruption of sphingolipid metabolism from the inhibition of ceramide synthesis leading to accumulation of free sphingoid bases, particularly sphinganine. The ability of FB1 to modulate signal transduction pathways plays a role in its toxicity. We recently reported that FB1 selectively and transiently activates protein kinase Calpha (PKCalpha) in porcine renal epithelial cells (LLC-PK1). The aim of current study was to investigate the effect of PKCalpha activation by FB1 on NF-kappaB activation and subsequently on TNFalpha gene expression and caspase 3 induction in LLC-PK1 cells. FB1 (1 micromol/L for 5 min) transiently activated PKCalpha and increased nuclear translocation of NF-kappaB, followed by their down-regulation at later time points. Preincubating the cells with the PKC inhibitor, calphostin C, prevented the activation of NF-kappaB by FB1. TNFalpha mRNA expression was increased after 15 min exposure to FB1 or the PKC activator, phorbol 12-myristate 13-acetate. In addition, an increase in caspase 3 activity was observed after addition of FB1 for 1 h. Calphostin C prevented both the FB1-induced increase in TNFalpha expression and caspase 3 activation. In summary, we hereby demonstrate that the FB1 activation of NF-kappaB and sequential induction of TNFalpha expression resulting in the subsequent increase in caspase 3 activity are all dependent on PKCalpha stimulation in LLC-PK1 cells.

Development and validation of CAPS and AFLP markers for white rust resistance gene in Brassica juncea

White rust, caused by Albugo candida, is a very serious disease in crucifers. In Indian mustard (Brassica juncea), it can cause a yield loss to the extent of 89.9%. The locus Ac2(t) controlling resistance to white rust in BEC-144, an exotic accession of mustard, was mapped using RAPD markers. In the present study, we developed: (1) a more tightly linked marker for the white rust resistance gene, using AFLP in conjunction with bulk segregant analysis, and (2) a PCR-based cleaved amplified polymorphic sequence (CAPS) marker for the closely linked RAPD marker, OPB06(1000). The data obtained on 94 RILs revealed that the CAPS marker for OPB06(1000) and the AFLP marker E-ACC/M-CAA(350) flank the Ac2(t) gene at 3.8 cM and 6.7 cM, respectively. Validation of the CAPS marker in two different F(2) populations of crosses Varuna x BEC-144 and Varuna x BEC-286 was also undertaken, which established its utility in marker-assisted selection (MAS) for white rust resistance. The use of both flanking markers in MAS would allow only 0.25% misclassification and thus provide greater efficiency to selection.

Antifungal activity of the stem bark of Ailanthus excelsa

The methanol extract of stem barks of Alianthus excelsa was partitioned with chloroform. The chloroform extract showed fungistatic and fungicidal activity against Aspergillus niger, A. fumigatus, Penicillium frequentence, P. notatum and Botrytis cinerea.

All-trans-retinoic acid-mediated modulation of p53 during neural differentiation in murine embryonic stem cells

All-trans-retinoic acid (RA) plays an important physiological role in embryonic development and is teratogenic in large doses in almost all species. p53, a tumor suppressor gene encodes phosphoproteins, which regulate cellular proliferation, differentiation, and apoptosis. Temporal modulation of p53 by retinoic acid was investigated in murine embryonic stem cells during differentiation and apoptosis. Undifferentiated embryonic stem cells express a high level of p53 mRNA and protein followed by a decrease in p53 levels as differentiation proceeds. The addition of retinoic acid during 8-10 days of differentiation increased the levels of p53 mRNA and protein, accompanied by accelerated neural differentiation and apoptosis. Marked increase in apoptosis was observed at 10-20 h after retinoic acid treatment when compared with untreated controls. Retinoic acid-induced morphological differentiation resulted in predominantly neural-type cells. Maximum increase in p53 mRNA in retinoic acid-treated cells occurred on day 17, whereas maximum protein synthesis occurred on days 14-17, which coincided with increased neural differentiation and proliferation. Increased p53 levels did not induce p21 transactivation, interestingly a decrease in p21 was observed on day 17 on exposure to retinoic acid. The level of p53 declined by day 21 of differentiation. The results demonstrated that retinoic acid-mediated apoptosis preceded the changes in p53 expression, suggesting that p53 induction does not initiate retinoic acid-induced apoptosis during development. However, retinoic acid accelerated neural differentiation and increased the expression of p53 in proliferating neural cells, corroborated by decreased p21 levels, indicating the importance of cell type and stage specificity of p53 function.

A Study On 453 Cases Of Epistaxis

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Fumonisin B1-induced localized activation of cytokine network in mouse liver

Fumonisin B1 (FB1), a mycotoxin produced primarily by Fusarium veticillioides and related fungi, is a carcinogen and causative agent of various animal diseases. Our previous studies indicated the involvement of tumor necrosis factor-alpha (TNFalpha) in FB1-induced hepatotoxicity. Male B6,129 mice (five/group) were injected subcutaneously with vehicle or 2.25 mg/kg/day of FB1 for 5 days and sampled 1 day after the last treatment. FB1 treatment caused an increased expression of TNFalpha, interferon gamma (IFNgamma) and interleukin (IL)-12 p40 in liver without any changes in kidney or spleen, suggesting the localized site of their production. IL-1beta cytokine expression was increased in liver and kidney after FB1 exposure. Cells involved in TNFalpha production after FB1 treatment in liver were identified as Kupffer cells. FB1 increased alanine aminotransferase in plasma and increased apoptotic cells in liver. Selective increase in proinflammatory T helper (Th)1-cytokines (IL-12 and IFNgamma) and TNFalpha with no alteration in Th2-cytokines (IL-4, IL-6 and IL-10) suggest the involvement of IL-12, produced by Kupffer cells, in induction of IFNgamma production by natural killer (NK) cells and/or NK1+ T cells, which can undergo a positive amplification loop with TNFalpha produced by macrophages or other hepatic cells to elicit the toxic reaction.

Blepharochalasis

A-16-year old female with laxity, atrophy, wrinkling and telangiectases of skin of both upper eyelids is being reported. These changes were preceded by recurrent, painless edema of eye lids, starting at the age of 14 years.

Persistence and reversibility of the elevation in free sphingoid bases induced by fumonisin inhibition of ceramide synthase

These studies determined (1) the time course for sphingoid base elevation in the small intestines, liver, and kidney of mice following a single 25 mg/kg body weight (bw) oral dose (high dose) of fumonisin B(1) (FB(1)), (2) the minimum threshold dose of FB(1) that would prolong the elevated sphingoid base concentration in kidney following the single high dose, and (3) the importance of the balance between the rate of sphingoid base biosynthesis and degradation in the persistence of sphingoid base accumulation. Following the high dose of FB(1), there was an increase in sphinganine in intestinal cells and liver that peaked at 4 to 12 h and declined to near the control level by 48 h. In kidney, sphinganine peaked at 6-12 h but remained elevated until 72 h, approaching control levels at 96-120 h. Oral administration of 0.03 mg FB(1)/kg bw (low dose) for 5 days had no effect on the sphingoid bases in kidney. However, following an initial high dose, daily administration of the low dose prolonged the elevation in kidney sphinganine compared to mice receiving a single high dose. Thus, a single exposure to a high dose of FB(1) followed by daily exposure at low levels will prolong the elevation of sphinganine in kidney. In cultured renal cells FB(1) was rapidly eliminated, but elevated sphinganine was persistent. This persistence in renal cells was rapidly reversed in the presence of the serine palmitoyltransferase inhibitor (ISP-1), indicating that the persistence was due to differences in the rates of sphinganine biosynthesis and degradation. The in vivo persistence in kidney may be due to similar differences.

Construction of an RAPD linkage map and localization of QTLs for oleic acid level using recombinant inbreds in mustard (Brassica juncea)

RAPD markers were employed for construction of a linkage map and localization of QTLs for oleic acid level using a set of 94 recombinant inbred lines (RILs) of mustard (Brassica juncea L.) as a mapping population. Only 30% of the 235 random primers used were useful in terms of polymorphism detected and the reproducibility of those patterns. Normal Mendelian segregation was observed for the majority of the 130 markers obtained with 71 informative primers; only 13.1% deviated (P < 0.01) from the expected 1:1 ratio. One-hundred and fourteen markers were assigned to 21 linkage groups (LGs) covering a total length of 790.4 cM with an average distance of 6.93 cM between markers. Two quantitative trait loci (QTL) for oleic acid level were mapped to 14- and 10.6-cM marker intervals on two different LGs. Both loci together explained 32.2% of phenotypic variance. One major QTL explained 28.5% of the trait variance observed in this species.

Multiple lentigenes syndrome

A 23-year-old male with multiple lentigenes, pulmonary stenosis, hyperelasticity of skin, hypermobile metacarpophalangeal joints is reported as a forme fruste form of leopard syndrome.

Superselective arterial embolization for the treatment of lower gastrointestinal hemorrhage

PURPOSE

To evaluate the technical feasibility, efficacy of hemostasis, recurrent bleeding, and ischemia resulting from superselective embolization of acute lower gastrointestinal (GI) hemorrhage.

MATERIALS AND METHODS

Fifty-two superselective mesenteric artery catheterization procedures were undertaken in 48 patients with angiographic evidence of lower GI bleeding. Embolization was performed only if the arterial recta leading to the bleed could be successfully catheterized (n = 39). The lesions treated were located in the colon (n = 33) and jejunum (n = 6). In 28 of 39 procedures, embolization was achieved by delivering polyvinyl alcohol (PVA) particles (150-500 microm) through a microcatheter. Microcoils were used as the sole embolic agent in four procedures and a combination of microcoils and PVA particles were used in another four. Gelfoam particles were used in three of our earliest procedures. Of the 35 patients who underwent embolization, 25 were evaluated for objective evidence of ischemia by endoscopy (n = 16) and/or histologic evaluation of the surgical specimen (n = 9); the remaining 10 patients were followed clinically.

RESULTS

Embolization was successful in 39 procedures involving 35 patients. Immediate hemostasis was achieved after embolization in all but two patients. Recurrent bleeding occurred in 12 other patients, eight patients underwent surgery, three were managed medically, and one underwent successful repeat embolization. Of the 25 patients evaluated for ischemia, mucosal ischemia was demonstrated in six (24%), but they remained asymptomatic and developed no sequelae as a result of ischemic changes on long-term follow-up. There was no incidence of clinically significant intestinal ischemia. Embolization alone was the definitive treatment in 44% patients (21 of 48). Reasons for unsuccessful superselective catheterization (27%) were small vessel spasm, cessation of bleeding, and vessel tortuosity.

CONCLUSION

Superselective embolization is a feasible, safe, and effective technique for treating acute lower GI hemorrhage.

Self-association of model transmembrane alpha-helices is modulated by lipid structure

We have developed a fluorescence quenching method using peptides containing 3,5-dibromotryrosine to measure oligomerization of model transmembrane alpha-helices in lipid bilayers. Peptides of the type Ac-LysLysGlyLeu(m)XLeu(n)LysLysAla-amide where X is tryptophan or 3,5-dibromotyrosine were found to form heterodimers in bilayers of phosphatidylcholine in the liquid-crystalline phase. The free energy of dimer formation changed little with increasing number of Leu residues from 16 to 22 but increased with increasing phospholipid fatty acyl chain length, with a slope of about 0.5 kJ mol(-1) per fatty acyl chain carbon. Peptides were excluded from lipid in the gel phase, resulting in increased levels of oligomerization. Addition of cholesterol to form the liquid-ordered state led to increased dimerization but without phase separation. The presence of phosphatidylethanolamine had little effect on dimerization.

Gender-dependent immunosuppression following subacute exposure to fumonisin B1

The effects of fumonisin B1 (FB1), a mycotoxin produced by Fusarium lertcillioides, on the immune system are controversial; FB1 exposure causing immunosuppression in poultry, swine, bovine and rodents species and immunostimulation in rodent species. The current study was conducted to examine the effects of FB1 on the immune system of BALB/c mice and to determine if there is sex specificity. Female and male mice (five per group) received five daily subcutaneous (s.c.) injections of 2.25 mg/kg/day of FB1, on the following day tissues were collected for immunological examinations. FB1 treatment dramatically reduced relative spleen and thymus weights in females, whereas there was no effect on organ weights in males. Exposure to FB1 reduced splenic cellularity and the basal rate of lymphocyte proliferation in females only. In addition, phytohemagglutinin (PHA-P)-induced T-lymphocyte and LPS-induced B-lymphocyte proliferation were reduced in female mice. Splenocytes from female mice exposed to FB1 showed a reduced expression of interleukin-2 mRNA. These changes occurred in the absence of alterations in tumor necrosis factor alpha or interleukin-1beta mRNA expression. Phenotypic analysis indicated that FB treatment caused a relative increase in the T-lymphocyte population in the spleen of female mice only. In contrast, FB1 dramatically reduced the immature CD4+/CD8+ double positive cell population in the thymus of females. No changes were evident in the thymocyte populations of male mice treated with FB1. The results of this study indicate that FB1 is immunosuppressive in mice; the magnitude of FB1-induced immunosuppression is highly dependent on sex, females being more susceptible than males.

CSF thyrotropin-releasing hormone concentrations differ in patients with schizoaffective disorder from patients with schizophrenia or mood disorders

OBJECTIVE

To determine if there were differences in CSF-TRH concentrations among several acute major psychiatric disorders and to investigate the effects of antipsychotic treatment on CSF-TRH levels.

METHOD

CSF-TRH concentrations were measured in 62 psychiatric inpatients during an acute phase of illness after a drug-free period. CSF-TRH measurements were repeated in 14 of these patients after 4 weeks of antipsychotic treatment.

RESULTS

Post-hoc tests (Tukey HSD) revealed significant differences among patients with schizoaffective disorder and both schizophrenia (P<0.03) and major depression (P<0.01). There were no significant differences between pre and posttreatment levels of CSF-TRH in the 14 patients treated with conventional agents for 4 weeks (1.54 pg/ml vs. 1.47 pg/ml). However, patients with a reduction in CSF-TRH concentration had a significantly better symptom response measured by the Brief Psychiatric Rating Scale (BPRS) positive factor (61% in six subjects) vs. those who had an increase in posttreatment CSF-TRH (29% in eight subjects; t=2.2; d.f.=12; P<0.04).

CONCLUSIONS

These results provide further evidence for a neuromodulatory role for TRH and suggest a re-examination of its behavioral effects and interactions with brain neurotransmitter systems relevant to major psychotic and mood disorders.

Gender-related differences in subacute fumonisin B1 hepatotoxicity in BALB/c mice

Fumonisin B1 (FB1), a potent mycotoxin prevalent in corn, is a carcinogen and causative agent of various animal diseases. Species and sex variations to chronic FB1 toxicity have been reported. Free sphingoid bases and cytokine levels are the two major biochemical alterations of FB1 in vivo and may explain any sex differences in FB1 toxicity. Male and female BALB/c mice (5/group) were injected subcutaneously with either saline vehicle or 2.25 mg/kg/day of FB1 for 5 days. One day after the last injection females showed a greater increase in circulating alanine aminotransferase and greater number of apoptotic cells in liver after FB1 treatment than males, indicating greater hepatotoxicity. Peripheral leukocytic counts, including neutrophils, were increased in females only after FB1 treatment. The increased toxicity in females correlated with a greater increase of sphinganine and sphingosine levels in liver after FB1 treatment compared to males. No sex differences in kidney sphinganine or sphingosine levels were observed after FB1 treatment. Previously we have shown the induction of tumor necrosis factor alpha (TNFalpha) in FB1-induced hepatotoxicity. While in males FB1 treatment caused increased expression of TNFalpha, interleukin (IL)-12 p40, interferon gamma (IFNgamma), IL-1beta, IL-6 and IL-10, females showed an increased expression of IL-6 only, and a downward modulation of IFNgamma, indicating gender differences in cytokine pathways in liver activated by FB1. The basal expression of TNFalpha, IL-12 p40, IL-1beta and IFNgamma in liver of females was higher compared to males. Gender differences in alterations of free sphingoid bases and cytokine modulation after FB1 treatment suggest their possible involvement in sex-dependent differential hepatotoxicity in mice.

A double-blind, randomized, prospective evaluation of the efficacy and safety of risperidone versus haloperidol in the treatment of schizoaffective disorder

The relative efficacy and safety of risperidone versus haloperidol in the treatment of schizoaffective disorder was studied. Sixty-two patients (29 depressed type; 33 bipolar type) entered a three-site, randomized, double-blind, 6-week trial of risperidone (up to 10 mg/day) or haloperidol (up to 20 mg/day). Trained raters assessed baseline, weekly, and end-of-study levels of psychopathology with the Positive and Negative Syndrome Scale (PANSS), the 24-item Hamilton Rating Scale for Depression (HAM-D-24) and the Clinician-Administered Rating Scale for Mania (CARS-M). The authors were unable to statistically distinguish between risperidone and haloperidol in the amelioration of psychotic and manic symptoms. In addition, there was no difference in worsening of mania between the two agents in either subgroup (i.e., depressed or bipolar subgroups). For the total PANSS, risperidone produced a mean decrease of 16 points from baseline compared with a 14-point decrease with haloperidol. For the total CARS-M scale, risperidone and haloperidol produced mean change scores of 5 and 8 points, respectively, and for the CARS-M Mania subscale, 3 and 7 points, respectively. Additionally, risperidone produced a mean decrease of 13 points from the baseline 24-item HAM-D, compared with an 8-point decrease with haloperidol. In those patients who had more severe depressive symptoms (i.e., HAM-D baseline score >20), risperidone produced at least a 50% mean improvement in 12 (75%) of 16 patients in comparison to 8 (38%) of 21 patients receiving haloperidol. Haloperidol produced significantly more extrapyramidal side effects and resulted in more dropouts caused by any side effect. There was no difference between risperidone and haloperidol in reducing both psychotic and manic symptoms in this group of patients with schizoaffective disorder. Risperidone did not demonstrate a propensity to precipitate mania and was better tolerated than haloperidol. In those subjects with higher baseline HAM-D scores (i.e., >20), risperidone produced a greater improvement in depressive symptoms than haloperidol.