Preclinical efficacy profiles of the sigma-1 modulator E1R and of fenfluramine in two chronic mouse epilepsy models.

OBJECTIVE: Given its key homeostatic role affecting mitochondria, ionotropic and metabotropic receptors, and voltage-gated ion channels, sigma-1 receptor (Sig1R) represents an interesting target for epilepsy management. Antiseizure effects of the positive allosteric modulator E1R have already been reported in acute seizure models. Although modulation of serotonergic neurotransmission is considered the main mechanism of action of fenfluramine, its interaction with Sig1R may be of additional relevance. METHODS: To further explore the potential of Sig1R as a target, we assessed the efficacy and tolerability of E1R and fenfluramine in two chronic mouse models, including an amygdala kindling paradigm and the intrahippocampal kainate model. The relative contribution of the interaction with Sig1R was analyzed using combination experiments with the Sig1R antagonist NE-100. RESULTS: Whereas E1R exerted pronounced dose-dependent antiseizure effects at well-tolerated doses in fully kindled mice, only limited effects were observed in response to fenfluramine, without a clear dose dependency. In the intrahippocampal kainate model, E1R failed to influence electrographic seizure activity. In contrast, fenfluramine significantly reduced the frequency of electrographic seizure events and their cumulative duration. Pretreatment with NE-100 reduced the effects of E1R and fenfluramine in the kindling model. Surprisingly, pre-exposure to NE-100 in the intrahippocampal kainate model rather enhanced and prolonged fenfluramine's antiseizure effects. SIGNIFICANCE: In conclusion, the kindling data further support Sig1R as an interesting target for novel antiseizure medications. However, it is necessary to further explore the preclinical profile of E1R in chronic epilepsy models with spontaneous seizures. Despite the rather limited effects in the kindling paradigm, the findings from the intrahippocampal kainate model suggest that it is of interest to further assess a possible broad-spectrum potential of fenfluramine.

Dose intensity and treatment duration of bortezomib in transplant-ineligible newly diagnosed multiple myeloma.

BACKGROUND: Bortezomib-related peripheral neuropathy (PN) affects a relevant proportion of multiple myeloma (MM) patients treated with melphalan, prednisone, and bortezomib (VMP). Empirical dose modifications have attempted to reduce toxicity without compromising efficacy. PATIENTS AND METHODS: We retrospectively evaluated the dose-response and dose-toxicity relationships in 114 unselected untreated MM patients intended for treatment with VMP with subcutaneous bortezomib. RESULTS: Sixty-two patients (54%) completed the 9 scheduled cycles. Median treatment duration was 48 weeks (range 1-57), cumulative bortezomib dose was 41.8 mg/m2 (2.6-67.6) and median dose intensity was 1.0 mg/m2 /wk (0.2-2.6). Median progression-free survival (PFS) and overall survival (OS) for the full cohort were 86 weeks (95%CI 77-104) and 209 weeks (95% CI 157-259) respectively. Patients who progressed <60 days after discontinuing bortezomib had received a significantly inferior mean cumulative dose, 34.6 mg/m2 than the remaining individuals, 45.5 (P = .023). PFS was significantly improved for patients achieving a very good partial response (VGPR) or better (P = .00007). Additional variables with a prognostic impact on PFS on univariate analysis included completion of the 9 scheduled cycles (P = .00002), patients with at least 50 weeks of treatment (P = .02) and patients receiving a cumulative dose of at least 49 mg/m2 (P = .05). Achievement of a VGPR (HR 0.23; 95%CI 0.12-0.46; P = .00002) and a cumulative dose of 49 mg/m2 (HR 0.46, 95%CI 0.27-0.78; P = .003) were statistically independent prognostic factors for PFS. Toxicity-related treatment dose reductions occurred in 75 individuals (66%). PN was observed in 50 individuals (44.6%), grade 3 in 9 (8%). The only prognostic factor for emergence of PN in multivariate analysis was the presence of baseline PN. CONCLUSIONS: Biweekly full-dose treatment in the first cycles has a major impact in depth of response. Depth of response, cumulative bortezomib dose, and treatment duration had an impact in prolongation of PFS.

Grain Inorganic Arsenic Content in Rice Managed Through Targeted Introgressions and Irrigation Management.

Arsenic (As) accumulation in rice grain is a significant public health concern. Inorganic As (iAs) is of particular concern because it has increased toxicity as compared to organic As. Irrigation management practices, such as alternate wetting and drying (AWD), as well as genotypic differences between cultivars, have been shown to influence As accumulation in rice grain. A 2 year field study using a Lemont × TeQing backcross introgression line (TIL) mapping population examined the impact of genotype and AWD severity on iAs grain concentrations. The "Safe"-AWD [35-40% soil volumetric water content (VWC)] treatment did not reduce grain iAs levels, whereas the more severe AWD30 (25-30% VWC) consistently reduced iAs concentrations across all genotypes. The TILs displayed a range of iAs concentrations by genotype, from less than 10 to up to 46 µg kg-1 under AWD30 and from 28 to 104 µg kg-1 under Safe-AWD. TIL grain iAs concentrations for flood treatments across both years ranged from 26 to 127 µg kg-1. Additionally, seven quantitative trait loci (QTLs) were identified in the mapping population associated with grain iAs. A subset of eight TILs and their parents were grown to confirm field-identified grain iAs QTLs in a controlled greenhouse environment. Greenhouse results confirmed the genotypic grain iAs patterns observed in the field; however, iAs concentrations were higher under greenhouse conditions as compared to the field. In the greenhouse, the number of days under AWD was negatively correlated with grain iAs concentrations. Thus, longer drying periods to meet the same soil VWC resulted in lower grain iAs levels. Both the number and combinations of iAs-affecting QTLs significantly impacted grain iAs concentrations. Therefore, identifying more grain iAs-affecting QTLs could be important to inform future breeding efforts for low iAs rice varieties. Our study suggests that coupling AWD practices targeting a soil VWC of less than or equal to 30% coupled with the use of cultivars developed to possess multiple QTLs that negatively regulate grain iAs concentrations will be helpful in mitigating exposure of iAs from rice consumption.

Fecal indicator bacteria, fecal source tracking markers, and pathogens detected in two Hudson River tributaries.

Volunteer monitoring in the Hudson River watershed since 2012 has identified that the Wallkill River and Rondout Creek tributary complex have elevated concentrations of the fecal indicator bacteria, enterococci. Concentrations of enterococci do not provide insight into the sources of pollution and are imperfect indicators of health risks. In 2017, the regular monthly volunteer monitoring campaign for culturable enterococci at 24 sites on the Wallkill and Rondout expanded to include: (1) culturable measurements of E. coli and quantification of E. coli and Enterococcus specific markers vis nanoscale qPCR, (2) microbial source tracking (MST) assays (avian, human, bovine, and equine) via real time PCR and nanoscale qPCR, and 3) quantification of 12 gastrointestinal pathogens including viruses, bacteria, and protozoa via nanoscale qPCR. Three human associated MST markers (HumM2, HF183, and B. theta) corroborated that human pollution was present in Rondout Creek and widespread in the Wallkill River. The presence of B. theta was associated with increased concentrations of culturable E. coli. Genes for adenovirus 40 and 41 conserved region, rotavirus A NSP3, E. coli eae and stx1, and Giardia lamblia 18S rRNA were detected in >45% of samples. Abundance of rotavirus A NSP3 genes was significantly correlated to the bovine marker gene, CowM3, though wild bird sources cannot be ruled out. This is the first study to investigate potential fecal pollution sources and pathogen concentrations in Hudson tributaries during the months of peak recreational use.

Microbial communities controlling methane and nutrient cycling in leach field soils.

Septic systems inherently rely on microbial communities in the septic tank and leach field to attenuate pollution from household sewage. Operating conditions of septic leach field systems, especially the degree of water saturation, are likely to impact microbial biogeochemical cycling, including carbon (C), nitrogen (N), and phosphorus (P), as well as greenhouse gas (GHG) emissions to the atmosphere. To study the impact of flooding on microbial methane (CH4) and nutrient cycling, two leach field soil columns were constructed. One system was operated as designed and the other was operated in both flooded and well-maintained conditions. CH4 emissions were significantly higher in flooded soils (with means between 0.047 and 0.33 g CH4 m-2 d-1) as compared to well-drained soils (means between -0.0025 and 0.004 g CH4 m-2 d-1). Subsurface CH4 profiles were also elevated under flooded conditions and peaked near the wastewater inlet. Gene abundances of mcrA, a biomarker for methanogens, were also greatest near the wastewater inlet. In contrast, gene abundances of pmoA, a biomarker for methanotrophs, were greatest in surface soils at the interface of CH4 produced subsurface and atmospheric oxygen. 16S rRNA, mcrA, and pmoA amplicon library sequencing revealed microbial community structure in the soil columns differed from that of the original soils and was driven largely by CH4 fluxes and soil VWC. Additionally, active microbial populations differed from those present at the gene level. Flooding did not appear to affect N or P removals in the soil columns (between 75 and 99% removal). COD removal was variable throughout the experiment, and was negatively impacted by flooding. Our study shows septic system leach field soils are dynamic environments where CH4 and nutrients are actively cycled by microbial populations. Our results suggest proper siting, installation, and routine maintenance of leach field systems is key to reducing the overall impact of these systems on water and air quality.

Methane and nitrous oxide cycling microbial communities in soils above septic leach fields: Abundances with depth and correlations with net surface emissions.

Onsite septic systems use soil microbial communities to treat wastewater, in the process creating potent greenhouse gases (GHGs): methane (CH4) and nitrous oxide (N2O). Subsurface soil dispersal systems of septic tank overflow, known as leach fields, are an important part of wastewater treatment and have the potential to contribute significantly to GHG cycling. This study aimed to characterize soil microbial communities associated with leach field systems and quantify the abundance and distribution of microbial populations involved in CH4 and N2O cycling. Functional genes were used to target populations producing and consuming GHGs, specifically methyl coenzyme M reductase (mcrA) and particulate methane monooxygenase (pmoA) for CH4 and nitric oxide reductase (cnorB) and nitrous oxide reductase (nosZ) for N2O. All biomarker genes were found in all soil samples regardless of treatment (leach field, sand filter, or control) or depth (surface or subsurface). In general, biomarker genes were more abundant in surface soils than subsurface soils suggesting the majority of GHG cycling is occurring in near-surface soils. Ratios of production to consumption gene abundances showed a positive relationship with CH4 emissions (mcrA:pmoA, p < 0.001) but not with N2O emission (cnorB:nosZ, p > 0.05). Of the three measured soil parameters (volumetric water content (VWC), temperature, and conductivity), only VWC was significantly correlated to a biomarker gene, mcrA (p = 0.0398) but not pmoA or either of the N2O cycling genes (p > 0.05 for cnorB and nosZ). 16S rRNA amplicon library sequencing results revealed soil VWC, CH4 flux and N2O flux together explained 64% of the microbial community diversity between samples. Sequencing of mcrA and pmoA amplicon libraries revealed treatment had little effect on diversity of CH4 cycling organisms. Overall, these results suggest GHG cycling occurs in all soils regardless of whether or not they are associated with a leach field system.