Modulation of extrasynaptic GABAA alpha 5 receptors in the ventral hippocampus normalizes physiological and behavioral deficits in a circuit specific manner.

Hippocampal hyperactivity is correlated with psychosis in schizophrenia patients and likely attributable to deficits in GABAergic signaling. Here we attempt to reverse this deficit by overexpression of the α5-GABAA receptor within the ventral hippocampus (vHipp). Indeed, this is sufficient to normalize vHipp activity and downstream alterations in dopamine neuron function in the MAM rodent model. This approach also attenuated behavioral deficits in cognitive flexibility. To understand the specific pathways that mediate these effects, we used chemogenetics to manipulate discrete projections from the vHipp to the nucleus accumbens (NAc) or prefrontal cortex (mPFC). We found that inhibition of the vHipp-NAc, but not the vHipp-mPFC pathway, normalized aberrant dopamine neuron activity. Conversely, inhibition of the vHipp-mPFC improved cognitive function. Taken together, these results demonstrate that restoring GABAergic signaling in the vHipp improves schizophrenia-like deficits and that distinct behavioral alterations are mediated by discrete projections from the vHipp to the NAc and mPFC.

A new reactor for denitrification and micro-particle removal in recirculated aquaculture systems.

A 'membrane-denitrification' reactor (MDR) was developed and tested in a semi-technical recirculation aquaculture system in comparison to a double - without MDR - as reference system. The MDR consisted of a reactor with an ultrafiltration membrane unit for removal of micro-particles (e.g. sludge flocs, bacteria and parasites). Specific carrier material provided surfaces for biofilm growth in a fluidized bed reactor with ethanol as carbon source for denitrification. The continuous motion of these carriers cleaned the membrane surface. With online and laboratory measurements of water parameters and operational data the feasibility of the concept was verified. An advantage is that no chemicals are needed to clean the membranes. Examinations of the fish and water analyses proved an MDR can positively influence cortisol, as a stress marker, and the microflora of the aquatic system.

Activation of a ventral hippocampus-medial prefrontal cortex pathway is both necessary and sufficient for an antidepressant response to ketamine.

A single sub-anesthetic dose of ketamine exerts rapid and sustained antidepressant effects. Here, we examined the role of the ventral hippocampus (vHipp)-medial prefrontal cortex (mPFC) pathway in ketamine's antidepressant response. Inactivation of the vHipp with lidocaine prevented the sustained, but not acute, antidepressant-like effect of ketamine as measured by the forced swim test (FST). Moreover, optogenetic as well as pharmacogenetic specific activation of the vHipp-mPFC pathway using DREADDs (designer receptors exclusively activated by designer drugs) mimicked the antidepressant-like response to ketamine; importantly, this was pathway specific, in that activation of a vHipp to nucleus accumbens circuit did not do this. Furthermore, optogenetic inactivation of the vHipp/mPFC pathway at the time of FST completely reversed ketamine's antidepressant response. In addition, we found that a transient increase in TrkB receptor phosphorylation in the vHipp contributes to ketamine's sustained antidepressant response. These data demonstrate that activity in the vHipp-mPFC pathway is both necessary and sufficient for the antidepressant-like effect of ketamine.

Ceramic membrane ultrafiltration of natural surface water with ultrasound enhanced backwashing.

Ultrafiltration membrane cleaning with ultrasound enhanced backwashing was investigated with two ceramic membrane systems in parallel. One of them was subjected to ultrasound during backwashing, the other acted as a reference system. The feed water was directly taken from a creek with a sedimentation process as only pre-treatment. The cleaning performance was improved with ultrasound but after 3 weeks of operation damages occurred on the membranes. These effects were studied with online measurements of flux, trans-membrane-pressure and temperature, but also with integrity tests, turbidity measurements and visual examination.

Denitrification with polycaprolactone as solid substrate in a laboratory-scale recirculated aquaculture system.

A denitrification system based on the biodegradable polymer Poly-epsilon-Caprolactone (PCL) was tested in a laboratory-scale recirculated aquaculture system with eels in comparison to a reference system without denitrification. The experiments were conducted with fluidized bed reactors in two parallel systems to examine the feasibility and performance of the process and to observe the condition of fishes by measuring weight gain during the test-period. The most evident effect of the system with denitrification was the low nitrate concentration compared with the untreated reference system. A further advantage was the stability of the pH in the systems with denitrification whereas pH of the untreated water decreased due to nitrification. All over the test-period the eels showed a similar weight gain in both systems.

Identity and potential functions of heterotrophic bacterial isolates from a continuous-upflow fixed-bed reactor for denitrification of drinking water with bacterial polyester as source of carbon and electron donor.

A collection of 186 heterotrophic bacteria, isolated directly from a continuous-upflow fixed-bed reactor for the denitrification of drinking water, in which poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) granules acted as biofilm carrier, carbon source and electron donor, was studied with regard to taxonomic affiliation and degradation and denitrification characteristics. Two granule samples were taken from a fully operating reactor for enumeration and isolation of heterotrophic bacteria. One sample was drawn from the lower part of the reactor, near the oxic zone, and the other sample from the upper, anoxic part of the fixed bed. Dominant colonies were isolated and the cultures were identified using fatty acid analysis and 16S rDNA sequencing. Their ability to degrade the polymer and 3-hydroxybutyrate and to denitrify in pure culture was assessed. The results show that high numbers of heterotrophic bacteria were present in the biofilms on the polymer granules, with marked differences in taxonomic composition and potential functions between the lower and upper part of the fixed bed. The majority of the isolates were Gram negative bacteria, and most of them were able to reduce nitrate to nitrite or to denitrify, and to utilize 3-hydroxybutyrate as sole source of carbon. Only two groups, one identified as Acidovorax facilis and the other phylogenetically related to Brevundimonas intermedia, could combine denitrification and utilization of poly(3-hydroxybutyrate) (PHB), and were found only in the upper sample. The other groups occurred either in the lower or upper part, or in both samples. They were assigned to Brevundimonas, Pseudomonas, Agrobacterium, Achromobacter, or Phyllobacterium, or were phylogenetically related to Afipia or Stenotrophomonas.

Seroepidemiology of low and high oncogenic risk types of human papillomavirus in a predominantly male cohort of STD clinic patients.

Human papillomaviruses (HPV) infecting the genital tract are associated with warts and anogenital malignancies. Although HPV is a highly prevalent sexually transmitted disease (STD), the majority of research has focused on female cohorts due to gender specific sequelae. Our objective was to measure the epidemiological features and seroprevalences of HPV-6/11 and 16 in a predominantly male group of STD clinic patients. High-risk individuals (n=687), who attended the public STD clinic were administered a behavioural questionnaire and serum tested for antibodies against HPV-6/11 and HPV-16 capsids via capture enzyme-linked immunosorbent assay. Despite the male predominance in this study, women were significantly more likely to have antibodies against both HPV-6/11 and HPV-16. Condom use appeared to be partially protective against HPV-16 seropositivity only. In conclusion, despite exhibiting increased risk behaviour, men were less likely to be HPV seropositive. Additional studies utilizing male cohorts are warranted to further elucidate this phenomenon.

Studies on the refrigerated storage of wheat (Triticum aestivum). 2. Ergosterol, xanthomegnin, viomellein and brevianamide A after inoculation with Penicillium viridicatum.

Wheat seed was adjusted to 18, 20, 22, 24 and 26% moisture content (m.c.), and stored for 240 days at 4 or 10 degrees C following inoculation with a strain of Penicillium viridicatum producing the toxins, xanthomegnin (XA), viomellein (VIO), and brevianamide A (BA). Wheat kernels were not sterilized before inoculation. The concentration of ergosterol (ERG), a chemical indicator of fungal biomass, remained constant at 18% m.c./4 degrees C, but increased under the other conditions. The time before a detectable increase of ERG concentration was higher and the rate of ERG production lower with decreasing moisture content and temperature. XA and BA were produced at both temperatures at 20-26% m.c., VIO was produced at 22-26% m.c./4 degrees C and 20-26% m.c./10 degrees C. The results suggest or indicate that the onset of XA, VIO and BA production (detection limits: 10, 15, and 0.1 micrograms/kg, respectively) coincided with the onset of ERG production. Maximum toxin contents were lower with decreasing moisture content at both temperatures, but were similar at 4 and 10 degrees C at 22-26% m.c. It is concluded that wheat contaminated with P. viridicatum should not be stored beyond the onset of ergosterol production; maximum storage periods are recommended.

[Cold storage of wheat. 1. Ergosterol, ochratoxin A and citrinin after inoculation with Penicillium verrucosum]. / Untersuchungen zur Kühllagerung von Weizen. 1. Mitteilung--Ergosterin, Ochratoxin A und Citrinin nach Zuimpfung von Penicillium verrucosum.

Seed wheat was inoculated without having been sterilized with an ochratoxin A and citrinin forming strain of Penicillium verrucosum and stored at moisture contents of 18, 20, 22, 24, and 26% at 10 and 4 degrees C. The production of ergosterol, a chemical indicator of fungal biomass, started within the storage time investigated (240 days). Only at 18% H2O/4 degrees C an increase of the ergosterol content was not observed. Ochratoxin A and Citrinin were not detected at 18% H2O/4 degrees C and 20% H2O/4 degrees C within 240 days (detection limit: 10 and 25 micrograms/kg, respectively). At the other combinations of moisture content and temperature the first detection of the two toxins approximately coincided with the onset of ergosterol production. With increasing moisture content and temperature the time up to the start of ergosterol production decreased, whereas the production rates of ergosterol, ochratoxin A and citrinin increased. Both toxins were produced with about the same rate during a first phase of accumulation. At 20-26% H2O there was no influence of moisture content and temperature on the relation between toxin content and the simultaneously reached ergosterol content. It is recommended that wheat highly contaminated with Penicillium verrucosum should not be stored beyond the start of ergosterol production.

[Effects of autoclaving and surface disinfection of wheat (Triticum aestivum) on the production of ergosterol, ochratoxin A and citrinin by Penicillium verrucosum]. / Einfluss von Autoklavierung und Oberflächendesinfektion von Weizen (Triticum aestivum) auf die Produktion von Ergosterin, Ochratoxin A und Citrinin durch Penicillium verrucosum.

Moist wheat was autoclaved, surface disinfected with NaOCl or left untreated. After inoculation with conidia of a toxigenic strain of Penicillium verrucosum kernels were stored at 10 and 4 degrees C. The production of ergosterol, a chemical indicator of fungal growth, was accelerated at both temperatures by each of the two treatments, compared to untreated wheat. The accumulation of ochratoxin A and citrinin was accelerated by each of the two treatments at 10 degrees C, whereas it was accelerated or retarded at 4 degrees C. It is concluded that the kinetics of growth and toxin production of Penicillium verrucosum during cold storage of wheat under real agricultural conditions cannot be predicted from in vitro studies with autoclaved or surface disinfected wheat.

Production of ochratoxin a, citrinin, and ergosterol byPenicillium viridicatum in autoclaved and non-autoclaved wheat at low temperature.

Wheat (moisture content: 26%) was autoclaved or left untreated, inoculated with conidia ofPenicillium viridicatum and stored at 10°C. The fungus grew on both substrates and was the dominant mould on the non-autoclaved grain. Autoclaving resulted in an earlier onset of ergosterol, ochratoxin A, and citrinin production due to accelerated mould growth. Yield of ochratoxin A increased while citrinin slightly decreased in autoclaved wheat.