Мінливість дуже сильних дощів і сильних злив в Україні

Розглянуто міжрічну мінливість кількості випадків стихійних гідрометеорологічних явищ (СГЯ), а саме: дуже сильних дощів і сильних злив – в Україні та її регіонах у другій половині ХХ – на початку ХХІ ст. Використавши методи сезонної декомпозиції, встановлено тенденцію динаміки цих рядів протягом досліджуваного періоду. Шляхом автокореляційного та спектрального аналізів визначено циклічні компоненти у структурі рядів річної кількості випадків СГЯ та їх особливості в періоди, коли спостерігали тенденцію до зменшення і збільшення інтенсивності цих явищ.Рассмотрена межгодовая изменчивость количества случаев очень сильных дождей и сильных ливней в Украине и ее регионах во второй половине ХХ - в начале ХХІ в. Установлена тенденция динамики этих рядов на протяжении исследуемого периода. Определены циклические компоненты в структуре рядов годового количества случаев стихийных осадков (СГЯ) и их особенности в периоды, когда наблюдали тенденцию к уменьшению и увеличению интенсивности этих явлений

The role of Toll-like receptor-4 in pertussis vaccine-induced immunity

<p>Abstract</p> <p>Background</p> <p>The gram-negative bacterium <it>Bordetella pertussis </it>is an important causative agent of pertussis, an infectious disease of the respiratory tract. After introduction of whole-cell vaccines (wP) in the 1950's, pertussis incidence has decreased significantly. Because wP were found to be reactogenic, in most developed countries they have been replaced by acellular vaccines (aP). We have previously shown a role for Toll-like receptor 4 (Tlr4) in pertussis-infected mice and the pertussis toxin (Ptx)-IgG response in wP-vaccinated children, raising the issue of the relative importance of Tlr4 in wP vaccination of mice. Here we analyze the effects of wP and aP vaccination and <it>B. pertussis </it>challenge, in <it>Tlr4</it>-deficient C3H/HeJ and wild-type C3H/HeOuJ mice. aP consists of Ptx, filamentous hemagglutinin (FHA), and pertactin (Prn).</p> <p>Results</p> <p>We show an important role of Tlr4 in wP and (to a lesser extent) aP vaccination, induction of Th1 and Th17 cells by wP but not aP vaccination, and induction of Th17 cells by infection, confirming data by Higgins et al. (<it>J Immunol </it>2006, <b>177:</b>7980–9). Furthermore, in <it>Tlr4</it>-deficient mice, compared to wild-type controls (i) after vaccination only, Ptx-IgG (that was induced by aP but not wP vaccination), FHA-IgG, and Prn-IgG levels were similar, (ii) after infection (only), lung IL-1α and IL-1β expression were lower, (iii) after wP vaccination and challenge, Prn-IgG level and lung IL-5 expression were higher, while lung IL-1β, TNF-α, IFN-γ, IL-17, and IL-23 expression were lower, and lung pathology was absent, and (iv) after aP vaccination and challenge, Prn-IgG level and lung IL-5 expression were higher, while Ptx-IgG level was lower.</p> <p>Conclusion</p> <p>Tlr4 does not influence the humoral response to vaccination (without challenge), plays an important role in natural immunity, wP and aP efficacy, and induction of Th1 and Th17 responses, is critical for lung pathology and enhances pro-inflammatory cytokine production after wP vaccination and challenge, and diminishes Th2 responses after both wP and aP vaccination and challenge. wP vaccination does not induce Ptx-IgG. A role for LPS in the efficacy of wP underlines the usefulness of LPS analogs to improve bacterial subunit vaccines such as aP.</p

An inter-laboratory effort to harmonize the cell-delivered in vitro dose of aerosolized materials

Air-liquid interface (ALI) lung cell models cultured on permeable transwell inserts are increasingly used for respiratory hazard assessment requiring controlled aerosolization and deposition of any material on ALI cells. The approach presented herein aimed to assess the transwell insert-delivered dose of aerosolized materials using the VITROCELL® Cloud12 system, a commercially available aerosol-cell exposure system. An inter-laboratory comparison study was conducted with seven European partners having different levels of experience with the VITROCELL® Cloud12. A standard operating procedure (SOP) was developed and applied by all partners for aerosolized delivery of materials, i.e., a water-soluble molecular substance (fluorescence-spiked salt) and two poorly soluble particles, crystalline silica quartz (DQ12) and titanium dioxide nanoparticles (TiO2 NM-105). The material dose delivered to transwell inserts was quantified with spectrofluorometry (fluorescein) and with the quartz crystal microbalance (QCM) integrated in the VITROCELL® Cloud12 system. The shape and agglomeration state of the deposited particles were confirmed with transmission electron microscopy (TEM). Inter-laboratory comparison of the device-specific performance was conducted in two steps, first for molecular substances (fluorescein-spiked salt), and then for particles. Device- and/or handling-specific differences in aerosol deposition of VITROCELL® Cloud12 systems were characterized in terms of the so-called deposition factor (DF), which allows for prediction of the transwell insert-deposited particle dose from the particle concentration in the aerosolized suspension. Albeit DF varied between the different labs from 0.39 to 0.87 (mean (coefficient of variation (CV)): 0.64 (28%)), the QCM of each VITROCELL® Cloud 12 system accurately measured the respective transwell insert-deposited dose. Aerosolized delivery of DQ12 and TiO2 NM-105 particles showed good linearity (R2 > 0.95) between particle concentration of the aerosolized suspension and QCM-determined insert-delivered particle dose. The VITROCELL® Cloud 12 performance for DQ12 particles was identical to that for fluorescein-spiked salt, i.e., the ratio of measured and salt-predicted dose was 1.0 (29%). On the other hand, a ca. 2-fold reduced dose was observed for TiO2 NM-105 (0.54 (41%)), which was likely due to partial retention of TiO2 NM-105 agglomerates in the vibrating mesh nebulizer of the VITROCELL® Cloud12. This inter-laboratory comparison demonstrates that the QCM integrated in the VITROCELL® Cloud 12 is a reliable tool for dosimetry, which accounts for potential variations of the transwell insert-delivered dose due to device-, handling- and/or material-specific effects. With the detailed protocol presented herein, all seven partner laboratories were able to demonstrate dose-controlled aerosolization of material suspensions using the VITROCELL® Cloud12 exposure system at dose levels relevant for observing in vitro hazard responses. This is an important step towards regulatory approved implementation of ALI lung cell cultures for in vitro hazard assessment of aerosolized materials

Transferability and reproducibility of exposed air-liquid interface co-culture lung models

Background The establishment of reliable and robust in vitro models for hazard assessment, a prerequisite for moving away from animal testing, requires the evaluation of model transferability and reproducibility. Lung models that can be exposed via the air, by means of an air-liquid interface (ALI) are promising in vitro models for evaluating the safety of nanomaterials (NMs) after inhalation exposure. We performed an inter-laboratory comparison study to evaluate the transferability and reproducibility of a lung model consisting of the human bronchial cell line Calu-3 as a monoculture and, to increase the physiologic relevance of the model, also as a co-culture with macrophages (either derived from the THP-1 monocyte cell line or from human blood monocytes). The lung model was exposed to NMs using the VITROCELL® Cloud12 system at physiologically relevant dose levels. Results Overall, the results of the 7 participating laboratories are quite similar. After exposing Calu-3 alone and Calu-3 co-cultures with macrophages, no effects of lipopolysaccharide (LPS), quartz (DQ12) or titanium dioxide (TiO2) NM-105 particles on the cell viability and barrier integrity were detected. LPS exposure induced moderate cytokine release in the Calu-3 monoculture, albeit not statistically significant in most labs. In the co-culture models, most laboratories showed that LPS can significantly induce cytokine release (IL-6, IL-8 and TNF-α). The exposure to quartz and TiO2 particles did not induce a statistically significant increase in cytokine release in both cell models probably due to our relatively low deposited doses, which were inspired by in vivo dose levels. The intra- and inter-laboratory comparison study indicated acceptable interlaboratory variation for cell viability/toxicity (WST-1, LDH) and transepithelial electrical resistance, and relatively high inter-laboratory variation for cytokine production. Conclusion The transferability and reproducibility of a lung co-culture model and its exposure to aerosolized particles at the ALI were evaluated and recommendations were provided for performing inter-laboratory comparison studies. Although the results are promising, optimizations of the lung model (including more sensitive read-outs) and/or selection of higher deposited doses are needed to enhance its predictive value before it may be taken further towards a possible OECD guideline

An Air-liquid Interface Bronchial Epithelial Model for Realistic, Repeated Inhalation Exposure to Airborne Particles for Toxicity Testing.

For toxicity testing of airborne particles, air-liquid interface (ALI) exposure systems have been developed for in vitro tests in order to mimic realistic exposure conditions. This puts specific demands on the cell culture models. Many cell types are negatively affected by exposure to air (e.g., drying out) and only remain viable for a few days. This limits the exposure conditions that can be used in these models: usually relatively high concentrations are applied as a cloud (i.e., droplets containing particles, which settle down rapidly) within a short period of time. Such experimental conditions do not reflect realistic long-term exposure to low concentrations of particles. To overcome these limitations the use of a human bronchial epithelial cell line, Calu-3 was investigated. These cells can be cultured at ALI conditions for several weeks while retaining a healthy morphology and a stable monolayer with tight junctions. In addition, this bronchial model is suitable for testing the effects of repeated exposures to low, realistic concentrations of airborne particles using an ALI exposure system. This system uses a continuous airflow in contrast to other ALI exposure systems that use a single nebulization producing a cloud. Therefore, the continuous flow system is suitable for repeated and prolonged exposure to airborne particles while continuously monitoring the particle characteristics, exposure concentration, and delivered dose. Taken together, this bronchial model, in combination with the continuous flow exposure system, is able to mimic realistic, repeated inhalation exposure conditions that can be used for toxicity testing

An inter-laboratory effort to harmonize the cell-delivered in vitro dose of aerosolized materials

Air-liquid interface (ALI) lung cell models cultured on permeable transwell inserts are increasingly used for respiratory hazard assessment requiring controlled aerosolization and deposition of any material on ALI cells. The approach presented herein aimed to assess the transwell insert-delivered dose of aerosolized materials using the VITROCELL® Cloud12 system, a commercially available aerosol-cell exposure system. An inter-laboratory comparison study was conducted with seven European partners having different levels of experience with the VITROCELL® Cloud12. A standard operating procedure (SOP) was developed and applied by all partners for aerosolized delivery of materials, i.e., a water-soluble molecular substance (fluorescence-spiked salt) and two poorly soluble particles, crystalline silica quartz (DQ 12) and titanium dioxide nanoparticles (TiO 2 NM-105). The material dose delivered to transwell inserts was quantified with spectrofluorometry (fluorescein) and with the quartz crystal microbalance (QCM) integrated in the VITROCELL® Cloud12 system. The shape and agglomeration state of the deposited particles were confirmed with transmission electron microscopy (TEM). Inter-laboratory comparison of the device-specific performance was conducted in two steps, first for molecular substances (fluorescein-spiked salt), and then for particles. Device- and/or handling-specific differences in aerosol deposition of VITROCELL® Cloud12 systems were characterized in terms of the so-called deposition factor (DF), which allows for prediction of the transwell insert-deposited particle dose from the particle concentration in the aerosolized suspension. Albeit DF varied between the different labs from 0.39 to 0.87 (mean (coefficient of variation (CV)): 0.64 (28%)), the QCM of each VITROCELL® Cloud 12 system accurately measured the respective transwell insert-deposited dose. Aerosolized delivery of DQ 12 and TiO 2 NM-105 particles showed good linearity (R 2 > 0.95) between particle concentration of the aerosolized suspension and QCM-determined insert-delivered particle dose. The VITROCELL® Cloud 12 performance for DQ 12 particles was identical to that for fluorescein-spiked salt, i.e., the ratio of measured and salt-predicted dose was 1.0 (29%). On the other hand, a ca. 2-fold reduced dose was observed for TiO 2 NM-105 (0.54 (41%)), which was likely due to partial retention of TiO 2 NM-105 agglomerates in the vibrating mesh nebulizer of the VITROCELL® Cloud12. This inter-laboratory comparison demonstrates that the QCM integrated in the VITROCELL® Cloud 12 is a reliable tool for dosimetry, which accounts for potential variations of the transwell insert-delivered dose due to device-, handling- and/or material-specific effects. With the detailed protocol presented herein, all seven partner laboratories were able to demonstrate dose-controlled aerosolization of material suspensions using the VITROCELL® Cloud12 exposure system at dose levels relevant for observing in vitro hazard responses. This is an important step towards regulatory approved implementation of ALI lung cell cultures for in vitro hazard assessment of aerosolized materials

Developmental immunotoxicity in male rats after juvenile exposure to ethanol

The aim of the present study was to determine the sensitivity of the developing immune system to ethanol (EtOH) after exposure from postnatal day (PND) 10 onward. Adult Wistar dams and litters were exposed to EtOH via drinking water (0, 0.25, 1.5, 2.75, 4, 5.25, or 6.5% (w/v) EtOH ad libitum) and drinking water exposure of the F-1 was continued from weaning until sacrifice. Immune assessments were performed at postnatal days (PNDs) 21, 42, and 70. Furthermore, Keyhole Limpet Hemocyanin (KLH) specific immune responses were evaluated following subcutaneous immunizations on PNDs 21 and 35. EtOH exposure affected innate immune responses, such as LPS-induced NO-production by adherent splenocytes, as well as adaptive immune responses as represented by KLH-specific parameters. The most sensitive developmental parameters included effects on maternal and pup bodyweight with calculated BMDs of 4.0% and 4.3% EtOH, respectively. The most sensitive immune parameters were affected at dose levels lower than those affecting developmental parameters and included KLH-specific immune responses, LPS-induced NO production by adherent splenocytes, and IL-10 production by ConA stimulated splenocytes. Calculated BMDs for these parameters were between 0.01% and 0.1% EtOH. A comparison of the results of this juvenile study with an extended one-generation reproductive toxicity study revealed that the juvenile study design may result in a higher sensitivity related to differences in the exposure design. These findings demonstrate the relative sensitivity of the developing immune system for EtOH exposure, the additional value of assessing functional immune parameters, and the importance of the juvenile window in developmental immunotoxicity testing

Effects of a Diphtheria-Tetanus-Acellular Pertussis Vaccine on Immune Responses in Murine Local Lymph Node and Lung Allergy Models

We have previously shown that in mice, diphtheria-tetanus-acellular pertussis (DTaP) vaccination before Bordetella pertussis infection resulted in, besides effective clearance, immediate hypersensitivity (lung eosinophilia, increased total serum immunoglobulin E [IgE], and increased ex vivo Th2 cytokine production by cells from the bronchial lymph nodes). To better appreciate the extent of these findings, we measured DTaP vaccination effects in the local lymph node assay (LLNA) and an ovalbumin (OVA) lung allergy model. In the LLNA, mice were vaccinated or adjuvant treated before being sensitized with trimellitic anhydride (TMA; inducing a Th2-directed response) and dinitrochlorobenzene (DNCB; inducing a Th1-directed response). Compared to the adjuvant-treated controls, the vaccinated mice showed a decreased response to TMA and (to a much lesser extent) an increased response to DNCB. The decreased response to TMA coincided with increased transforming growth factor β levels. With the exception of filamentous hemagglutinin, all vaccine constituents contributed to the decreased response to TMA. In the lung allergy model, sensitization induced OVA-specific IgE, lung pathology (peribronchiolitis, perivasculitis, and hypertrophy of the bronchiolar mucus cells) and increased the number of eosinophils, lymphocytes, and neutrophils in the bronchoalveolar lavage fluid. Vaccination failed to modulate these parameters. In conclusion, although DTaP vaccination may affect the LLNA response, we found no evidence of an effect on lung allergy

Developmental immunotoxicity testing of 4-methyl anisole

The developmental immunotoxicity of 4-methyl anisole (4MA) was investigated in the rat. Four study designs were used, with either premating or post-weaning onset of exposure, continued to postnatal day 50, and with or without additional oral gavage of pups from postnatal day 10 onward. Reduced litter size (benchmark dose lower confidence limit (BMDL) 80 mg/kg bw/day) was the most sensitive developmental parameter, with pup relative organ weight effects observed at similar BMDLs, in the absence of maternal toxicity. Eosinophil numbers were reduced at lower doses (BMDL 16 mg/kg bw/day). KLH challenge resulted in increased IL-13 and TNF-alpha responses, and variably reduced IgG production (BMDL 27 mg/kg bw/day). T-4 levels were reduced by 11% at maximum with a BMDL of 73 mg/kg bw/day. Differences between exposure cohorts were limited and were considered to be without biological significance. This study shows that 4MA induces developmental immunotoxicity at doses below those inducing developmental and general toxicity. These observations being independent of the study designs applied suggest that the post-weaning period, included in all designs, is the most relevant sensitive period for inducing 4MA mediated developmental immunotoxicity. Moreover, this study stresses the importance of including developmental immunotoxicity testing by default in regulatory toxicology. (C) 2015 Elsevier Inc. All rights reserved