Vector competence of Culicoides biting midges from Switzerland for African horse sickness virus and epizootic haemorrhagic disease virus.

INTRODUCTION: Culicoides biting midges unexpectedly arose in Europe as highly efficient vectors of bluetongue virus in the epidemics that started in the Netherlands in 2006. They are known vectors of other orbiviruses, such as African horse sickness (AHSV) and epizootic haemorrhagic disease viruses (EHDV), which are not endemic to Europe. We investigated whether Culicoides occurring in Switzerland at two altitudes (Swiss Plateau, 650 meters above sea level [masl]; and pre-alpine, 2,130 masl) can act as vectors for AHSV and EHDV (two strains each). Biting midges were collected from farms, allowed to feed on virus-spiked blood meals through an artificial membrane in the laboratory and incubated for eight days under two temperature regimes (22 ± 6 °C or 26 ± 6 °C) reflecting a summer day or a hot spell on the Swiss Plateau. Vector competence was assessed from head homogenates by RT-qPCR and virus isolation. Overall, over 15,000 biting midges were exposed to any one of the four viruses. Fully disseminated infections were identified for all four virus strains in 14 individuals (6 C. obsoletus, 8 C. scoticus, as identified by MALDI-TOF mass spectrometry), all originating from the Swiss Plateau, by RT-qPCR. Viable virus could be isolated from 8 of these specimens. Dissemination rates ranged from 1-5%. No viral dissemination was observed in biting midges from the high altitude, predominantly belonging to the species C. grisescens, which were only investigated at the high temperature regime. However, a multivariable logistic regression model revealed no statistical difference in the dissemination rates based on the origin of midges (altitude), virus strain or temperature regime. Thus, AHDV and EHDV transmission is feasible on the Swiss Plateau but unlikely in the pre-alpine area by considering vector abundance. Ways of potential virus introduction include illegal animal movement but also long-distance wind-dispersal of infectious Culicoides.

INTRODUCTION: Les moucherons culicoïdes sont apparus de manière inattendue en Europe en tant que vecteurs très efficaces du virus de la fièvre catarrhale du mouton lors des épidémies qui ont commencé aux Pays-Bas en 2006. Ils sont des vecteurs connus d'autres orbivirus, tels que la peste équine (AHSV) et la maladie à virus hémorragique épizootique (EHDV), qui ne sont pas endémiques en Europe. Nous avons cherché à savoir si les culicoïdes présents en Suisse à deux altitudes (Plateau suisse, 650 mètres au-dessus du niveau de la mer et Préalpes, 2130 mètres au-dessus du niveau de la mer) peuvent agir comme vecteurs pour l'AHSV et l'EHDV (deux souches chacune). Des moucherons piqueurs ont été collectés dans des élevages, laissés se nourrir de repas de sang contaminé par le virus à travers une membrane artificielle en laboratoire et incubés pendant huit jours sous deux régimes de température (22 ± 6 °C ou 26 ± 6 °C) reflétant une journée d'été ou une vague de chaleur sur le plateau suisse. La compétence vectorielle a été évaluée à partir d'homogénats de tête par RT-qPCR et isolement du virus. Dans l'ensemble, plus de 15 000 moucherons piqueurs ont été exposés à l'un des quatre virus. Des infections entièrement disséminées ont été identifiées pour les quatre souches virales chez 14 individus (6 C. obsoletus, 8 C. scoticus, identifiés par spectrométrie de masse MALDI-TOF), tous originaires du plateau suisse, par RT-qPCR. Le virus viable a pu être isolé à partir de 8 de ces échantillons. Les taux de diffusion allaient de 1 à 5 %. Aucune dissémination virale n'a été observée chez les moucherons piqueurs de haute altitude, appartenant majoritairement à l'espèce C. grisescens, qui n'ont été étudiées qu'au régime de haute température. Cependant, un modèle de régression logistique multivariable n'a révélé aucune différence statistique dans les taux de dissémination en fonction de l'origine des moucherons (altitude), de la souche virale ou du régime de température. Ainsi, la transmission de l'AHDV et de l'EHDV est possible sur le plateau suisse mais peu probable dans la zone préalpine en considérant l'abondance des vecteurs. Les voies d'introduction potentielle du virus comprennent les déplacements illégaux d'animaux, mais aussi la dispersion par le vent sur de longues distances de culicoïdes infectieux.

In situ localization of micropollutants and associated stress response in Populus nigra leaves.

Micropollutants and emerging organic contaminants (EOCs) have been widely studied in terms of persistance, removal, human risk assessment, toxicology, etc. Mass spectrometry imaging (MSI) offers the possibility of following the fate of a single pesticide in a plant leaf or a drug in the whole body of an animal, organ by organ. However, the admissibility of chronic low doses of complex mixtures for the ecosystem has not been assessed. How do micropollutants diffuse in the environment? How do living organisms cope with chronic exposure to a low dose of diverse micropollutants? Is there a cocktail effect or a chance for hormesis? Combining mass spectrometry imaging (MSI) and targeted and nontargeted liquid chromatography coupled to mass spectrometry (LC-MS), we attempt to answer these questions. We investigate the diversity of micropollutants at the exit of a water treatment facility, their diffusion in sludge and black poplar (Populus nigra), and their impact on a living organism. We reveal a specific tissue localization of micropollutants in peripheral leaf tissues, and an associated stress response from the plant, with stress hormones and tissue degradation markers induced in the plant growing near the water efflux.

Elevated water temperature increases the levels of reo-like virus and selected innate immunity genes in hemocytes and hepatopancreas of adult female blue crab, Callinectes sapidus.

Seasonal changes in water temperature directly affect the aquatic ecosystem. The blue crab, Callinectes sapidus, inhabiting the Chesapeake Bay has been adapted to seasonal changes of the environmental conditions. In this, the animals halt their physiological process of the growth and reproduction during colder months while they resume these processes as water temperatures increase. We aimed to understand the effect of the elevated temperatures on a disease progression of reo-like virus (CsRLV) and innate immunity of adult female C. sapidus. Following a rise in water temperature from 10 to 23 °C, CsRLV levels in infected crabs rose significantly in hemocytes and multiple organs. However, in hemocytes, the elevated temperature had no effect on the levels of three innate immune genes: Cas-ecCuZnSOD-2, CasPPO and CasLpR three carbohydrate metabolic genes: CasTPS, CasGlyP; and CasTreh and the total hemocyte counts (THC). Interestingly, the hemocytes of CsRLV infected animals exposed to 23 °C for 10 days had significantly elevated levels of Cas-ecCuZnSOD-2 and CasTPS, compared to those of the uninfected ones also exposed to the same condition and compared to hatchery-raised females kept at 23 °C. Despite the lack of changes in THC, the types of hemocytes from the animals with high CsRLV levels differed from those of uninfected ones and from hatchery animals kept at 23 °C: CsRLV-infected crabs had hemocytes of smaller size with less cytosolic complexity than uninfected crabs. It therefore appears that the change in temperature influences rapid replication of CsRLV in all internal tissues examined. This implies that CsRLV may have broad tissue tropism. Interestingly, the digestive tract (mid- and hindgut) contains significantly higher levels of CsRLV than hemocytes while hepatopancreas and ovary have lower levels than hemocytes. Innate immune responses differ by tissue: midgut and hepatopancreas with upregulated Cas-ecCuZnSOD-2 similar to that found in hemocytes. By contrast, hepatopancreas showed a down-regulated CasTPS, suggesting carbohydrate stress during infection.

Long-term treatment with L-DOPA or pramipexole affects adult neurogenesis and corresponding non-motor behavior in a mouse model of Parkinson's disease.

Non-motor symptoms such as hyposmia and depression are often observed in Parkinson's disease (PD) and can precede the onset of motor symptoms for years. The underlying pathological alterations in the brain are not fully understood so far. Dysregulation of adult neurogenesis in the dentate gyrus of the hippocampus and the olfactory bulb has been recently suggested to be implicated in non-motor symptoms of PD. However, there is so far no direct evidence to support the relationship of non-motor symptoms and the modulation of adult neurogenesis following dopamine depletion and/or dopamine replacement. In this study, we investigated the long-term effects of l-DOPA and pramipexole, a dopamine agonist, in a mouse model of bilateral intranigral 6-OHDA lesion, in order to assess the impact of adult neurogenesis on non-motor behavior. We found that l-DOPA and pramipexole can normalize decreased neurogenesis in the hippocampal dentate gyrus and the periglomerular layer of the olfactory bulb caused by a 6-OHDA lesion. Interestingly, pramipexole showed an antidepressant and anxiolytic effect in the forced swim test and social interaction test. However, there was no significant change in learning and memory function after dopamine depletion and dopamine replacement, respectively.

Estrogen plus progestin increase superoxide dismutase and total antioxidant capacity in postmenopausal women.

OBJECTIVE: This cross-sectional study aimed to evaluate the behavior of blood antioxidant enzymes (superoxide dismutase (SOD), catalase and glutathione peroxidase), plasma total antioxidant capacity and oxidative damage (lipid oxidation and protein carbonyl levels) and their relationship with the serum levels of steroid hormones in premenopausal and postmenopausal women without and with estrogen alone (ET) or estrogen plus progestin therapy (EPT). METHODS: Blood was collected from four groups of subjects: premenopausal women (n = 24), postmenopausal women without hormone therapy (n = 31), postmenopausal women with ET (n = 12) and postmenopausal women with EPT (n = 16). RESULTS: The activities of the different SOD isoforms (CuZnSOD and MnSOD) and the plasma total antioxidant power were significantly higher in the postmenopausal women under EPT than in the postmenopausal women without hormone replacement therapy (HRT). Only CuZnSOD activity was increased in women receiving ET compared to the postmenopausal women without HRT. However, no differences were observed in the levels of lipid or protein oxidation or in the non-enzymatic plasma antioxidants (uric acid and albumin) among the groups. The duration of HRT and serum estrogen levels were positively correlated to the blood CuZnSOD activity and to plasma total antioxidant power, whereas the serum progesterone levels were positively correlated to CuZnSOD activity and negatively correlated to protein carbonyl groups. Interestingly, the total antioxidant power of plasma was positively correlated to CuZnSOD and glutathione peroxidase activities. CONCLUSION: We conclude that EPT increases blood MnSOD and CuZnSOD activity in postmenopausal women, leading to an increased plasma total antioxidant capacity. This finding may be relevant to the prevention of oxidative stress-related disorders in postmenopausal women.

Non-genomic, direct modulatory effect of 17ß-estradiol, progesterone and their synthetic derivatives on the activity of human erythrocyte CuZn superoxide dismutase.

This study aimed to evaluate whether natural or synthetic steroid hormones could directly modulate the activity of the different superoxide dismutase (SOD) isoforms found in human blood fractions without changing enzyme expression. Enzyme samples of human erythrocytes, the human platelet-rich plasma fraction (PRP) or isolated CuZnSOD, which was purified from human erythrocytes were pre-incubated with natural steroids (17ß-estradiol 17-acetate and progesterone) and their synthetic derivatives (ß-estradiol 3-benzoate and medroxyprogesterone 17-acetate). Then, CuZn and MnSOD activities were measured using the xanthine/xanthine oxidase/nitroblue tetrazolium method. Hormones had no effect on MnSOD activity from the PRP, but we show for the first time that natural and synthetic steroid hormones have a direct, bell-shaped effect on the activity of CuZnSOD from both male and female human erythrocytes. Low (physiological) hormone concentrations caused a dose-dependent increase in enzyme activity, which disappeared at higher hormone concentrations. In addition, the combination of synthetic and natural estrogens and progestins had a synergistic stimulatory effect on the activity of CuZnSOD from human erythrocytes. The molecular interaction between CuZnSOD and steroid hormones was preliminarily studied. Natural hormones did not change the electrophoretic mobility of SOD under denaturing conditions, but they did increase the absorption spectra of SOD in the 230-290 nm range. These data suggest that hormone-mediated modulation of CuZnSOD is related to subtle changes in protein conformation, possibly related to Trp and Phe residues. We propose that this effect may account for the physiological regulation of enzyme activity during conditions where steroid hormones undergo alterations as the ovulatory cycle.

Microwave photon counter based on Josephson junctions.

We describe a microwave photon counter based on the current-biased Josephson junction. The junction is tuned to absorb single microwave photons from the incident field, after which it tunnels into a classically observable voltage state. Using two such detectors, we have performed a microwave version of the Hanbury Brown-Twiss experiment at 4 GHz and demonstrated a clear signature of photon bunching for a thermal source. The design is readily scalable to tens of parallelized junctions, a configuration that would allow number-resolved counting of microwave photons.

Differences in clinical trial patient attributes and outcomes according to enrollment setting.

PURPOSE: During the last 25 years, National Cancer Institute (NCI) cooperative trial groups have extended trial networks from academic centers to include certain community and Veterans Health Administration (VHA) centers. We compared trial patients' attributes and outcomes by these enrollment settings. PATIENTS AND METHODS: Studying 2,708 patients on one of 10 cooperative group, randomized lung trials at 272 institutions, we compared patient attributes by enrollment setting (ie, academic, community, and VHA affiliates). We used adjusted Cox regression to evaluate for survival differences by setting. RESULTS: Main member institutions enrolled 44% of patients; community affiliates enrolled 44%; and VHAs enrolled 12%. Patient attributes (ie, case-mix) of age, ethnicity, sex, and performance status varied by enrollment setting. After analysis was adjusted for patient case-mix, no mortality differences by enrollment setting were noted. CONCLUSION: Although trial patients with primarily advanced-stage lung cancer from nonacademic centers were older and had worse performance statuses than those from academic centers, survival did not differ by enrollment setting after analysis accounted for patient heterogeneity. An answer for whether long-term outcomes for patients at community and VHA centers affiliated with cooperative trial groups are equivalent to those at academic centers when care is delivered through NCI trials requires additional research among patients with longer survival horizons.

Acetate and formate stress: opposite responses in the proteome of Escherichia coli.

Acetate and formate are major fermentation products of Escherichia coli. Below pH 7, the balance shifts to lactate; an oversupply of acetate or formate retards growth. E. coli W3110 was grown with aeration in potassium-modified Luria broth buffered at pH 6.7 in the presence or absence of added acetate or formate, and the protein profiles were compared by two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Acetate increased the steady-state expression levels of 37 proteins, including periplasmic transporters for amino acids and peptides (ArtI, FliY, OppA, and ProX), metabolic enzymes (YfiD and GatY), the RpoS growth phase regulon, and the autoinducer synthesis protein LuxS. Acetate repressed 17 proteins, among them phosphotransferase (Pta). An ackA-pta deletion, which nearly eliminates interconversion between acetate and acetyl-coenzyme A (acetyl-CoA), led to elevated basal levels of 16 of the acetate-inducible proteins, including the RpoS regulon. Consistent with RpoS activation, the ackA-pta strain also showed constitutive extreme-acid resistance. Formate, however, repressed 10 of the acetate-inducible proteins, including the RpoS regulon. Ten of the proteins with elevated basal levels in the ackA-pta strain were repressed by growth of the mutant with formate; thus, the formate response took precedence over the loss of the ackA-pta pathway. The similar effects of exogenous acetate and the ackA-pta deletion, and the opposite effect of formate, could have several causes; one possibility is that the excess buildup of acetyl-CoA upregulates stress proteins but excess formate depletes acetyl-CoA and downregulates these proteins.