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Differential effects of size-specific particulate matter on emergency department visits for respiratory and cardiovascular diseases in Guangzhou, China
2018
Ge, Erjia | Lai, Kefang | Xiao, Xiong | Luo, Ming | Fang, Zhangfu | Zeng, Yanjun | Ju, Hong | Zhong, Nanshan
Studies differentiating the cardiorespiratory morbidity effects of PM₂.₅, PM₁₀, and PM₂.₅∼₁₀ (i.e. coarse PM or PMc) are still limited and inconsistent.To estimate the acute, cumulative, and harvesting effects of exposure to the three size-specific PM on cardiorespiratory morbidity, and their concentration-response relations.A total of 6,727,439 emergency department (ED) visits were collected from 16 public teaching hospitals in Guangzhou, from January 1st 2012 to December 31st 2015, among which over 2.1 million were asthma, COPD, pneumonia, respiratory tract infection (RTI), hypertension, stroke, and coronary heart disease (CHD). Distributed lag non-linear models (DLNM) was used to estimate the associations between the three size-specific PM and ED visits for the cardiovascular diseases. Long-term trends, seasonality, influenza epidemics, meteorological factors, and other gas pollutants, including SO2, NO₂, and O₃, were adjusted. We stratified the analyses by gender and age.Elevated PM₂.₅ and PM₁₀ were significantly associated with increased ED visits for pneumonia, RTI, and CHD at both lag₀ and lag₀₋₃. A 10 μg/m³ increment of PMc (at lag₀₋₁₄) was estimated to increase ED visits for pneumonia by 6.32% (95% CI, 4.19, 8.49) and for RTI by 4.72% (95% CI, 3.81, 5.63), respectively. PMc showed stronger cumulative effects on asthma in children than elderly. We observed significant harvesting effects (i.e. morbidity displacements) of the three size-specific PM on respiratory but very little on cardiovascular ED visits. The concentration-response curves suggested non-linear relations between exposures to the three different sizes of PM and respiratory morbidity.Overall, the three size-specific PM demonstrated distinct acute and cumulative effects on the cardiorespiratory diseases. PM₂.₅ and PMc would have significant effects on pneumonia and RTI. Strategies should be considered to further reduce levels of ambient PM₂.₅ and PMc.
Show more [+] Less [-]Titanium dioxide nanoparticles enhance mortality of fish exposed to bacterial pathogens
2015
Jovanović, Boris | Whitley, Elizabeth M. | Kimura, Kayoko | Crumpton, Adam | Palić, Dušan
Nano-TiO2 is immunotoxic to fish and reduces the bactericidal function of fish neutrophils. Here, fathead minnows (Pimephales promelas) were exposed to low and high environmentally relevant concentration of nano-TiO2 (2 ng g−1 and 10 μg g−1 body weight, respectively), and were challenged with common fish bacterial pathogens, Aeromonas hydrophila or Edwardsiella ictaluri. Pre-exposure to nano-TiO2 significantly increased fish mortality during bacterial challenge. Nano-TiO2 concentrated in the kidney and spleen. Phagocytosis assay demonstrated that nano-TiO2 has the ability to diminish neutrophil phagocytosis of A. hydrophila. Fish injected with TiO2 nanoparticles displayed significant histopathology when compared to control fish. The interplay between nanoparticle exposure, immune system, histopathology, and infectious disease pathogenesis in any animal model has not been described before. By modulating fish immune responses and interfering with resistance to bacterial pathogens, manufactured nano-TiO2 has the potential to affect fish survival in a disease outbreak.
Show more [+] Less [-]Changes in mycelia growth, sporulation, and virulence of Phytophthora capsici when challenged by heavy metals (Cu2+, Cr2+ and Hg2+) under acid pH stress
2018
Liu, Peiqing | Wei, Mengyao | Zhang, Jinzhu | Wang, Rongbo | Li, Benjin | Chen, Qinghe | Weng, Qiyong
Phytophthora capsici, an economically devastating oomycete pathogen, causes devastating disease epidemics on a wide range of vegetable plants and pose a grave threat to global vegetables production. Heavy metals and acid pH are newly co-occurring stresses to soil micro-organisms, but what can be expected for mycelia growth and virulence and how they injure the oomycetes (especially P. capsici) remains unknown. Here, the effects of different heavy metals (Cu²⁺, Cr²⁺, and Hg²⁺) on mycelia growth and virulence were investigated at different pHs (4.0 vs. 7.0) and the plausible molecular and physiological mechanisms were analyzed. In the present study, we compared the effective inhibition of different heavy metals (Cu²⁺, Cr²⁺, and Hg²⁺) and acid pH on a previously genome sequenced P. capsici virulent strain LT1534. Both stress factors independently affected its mycelia growth and sporulation. Next, we investigated whether ROS participated in the pH-inhibited mycelial growth, finding that the ROS scavenger, catalase (CAT), significantly inhibited the acid pH-induced ROS in mycelia. Additionally, because MAPK specially transmits different stress responsive signals in environment into cells, we employed CAT and a p38-MAPK pathway inhibitor to investigate ROS and p38-MAPK roles in heavy metal-inhibited mycelia growth at different pHs (4.0 vs. 7.0), finding that they significantly inhibited growth. Furthermore, ROS and p38-MAPK influenced the heavy metal-induced TBARS content, total antioxidant capacity (TAC), and CAT activity at different pHs, and also reduced the expression of infection-related laccases (PcLAC2) and an effector-related protein (PcNLP14). We propose that acid pH stress accelerates how heavy metals inhibit mycelium growth, sporulation, and virulence change in P. capsici, and posit that ROS and p38-MAPK function to regulate the molecular and physiological mechanisms underlying this toxicity. Although these stresses induce molecular and physiological challenges to oomycetes, much remains to be known the mechanisms dedicated to resolve these environmental stresses.
Show more [+] Less [-]Effects of sulfamethoxazole and sulfamethoxazole-degrading bacteria on water quality and microbial communities in milkfish ponds
2019
Chang, Bea-Ven | Chang, Yi-Tang | Chao, Wei-Liang | Yeh, Shinn-Lih | Kuo, Dong-Lin | Yang, Chu-Wen
Intensive farming practices are typically used for aquaculture. To prevent disease outbreaks, antibiotics are often used to reduce pathogenic bacteria in aquaculture animals. However, the effects of antibiotics on water quality and microbial communities in euryhaline fish culture ponds are largely unknown. The aim of this study was to investigate the interactions between sulfamethoxazole (SMX), water quality and microbial communities in milkfish (Chanos chanos) culture ponds. The results of small-scale milkfish pond experiments indicated that the addition of SMX decreased the abundance of ammonia-oxidizing bacteria (AOB), nitrite-oxidizing bacteria (NOB) and photosynthetic bacteria. Consequently, the levels of ammonia and total phosphorus in the fish pond water increased, causing algal and cyanobacterial blooms to occur. In contrast, the addition of the SMX-degrading bacterial strains A12 and L effectively degraded SMX and reduced the levels of ammonia and total phosphorus in fish pond water. Furthermore, the abundances of AOB, NOB and photosynthetic bacteria were restored, and algal and cyanobacterial blooms were inhibited. This study demonstrate the influences of SMX on water quality and microbial community composition in milkfish culture ponds. Moreover, the use of the bacterial strains A12 and L as dual function (bioaugmentation and water quality maintenance) beneficial bacteria was shown to provide an effective approach for the bioremediation of SMX-contaminated euryhaline milkfish culture ponds.
Show more [+] Less [-]Heavy oil exposure induces high moralities in virus carrier Japanese flounder Paralichthys olivaceus
2011
Song, Jun-Young | Nakayama, Kei | Murakami, Yasunori | Kitamura, Shin-Ichi
The relationship between chemical exposure and disease outbreak in fish has not been fully defined due to the limitations of experimental systems (model fish and pathogens). Therefore, we constructed a system using the Japanese flounder, Paralichthys olivaceus, and viral haemorrhagic septicemia virus (VHSV), and evaluated it by heavy oil (HO) exposure. The fish were exposed to HO at 0.3, 0.03, 0.003, and 0g/L following VHSV infection at doses of 10².⁵ or 10³.⁵ tissue culture infectious dose (TCID)₅₀/fish. As a result, groups given the dual stressors showed more than 90% mortality. Although VHSV infection at 10².⁵ and 10³.⁵ TCID₅₀/fish without HO exposure also induced high mortality, at 68.8% and 81.3%, respectively, HO exposure induced faster and higher mortality in the virus carrier fish, indicating that chemical stressors raise the risk of disease outbreak in fish. The experimental system established in this study could be useful for chemical risk assessment.
Show more [+] Less [-]Recurrent disease outbreak in a warm temperate marginal coral community
2022
Heitzman, Joshua M. | Caputo, Nicolè | Yang, Sung-Yin | Harvey, Ben P. | Agostini, Sylvain
Coral diseases contribute to the rapid degradation of coral reefs on a global scale. Although widespread in tropical and subtropical reefs, disease outbreaks have not been described in warm temperate areas. Here, we report the outbreak of a new coral disease in a warm temperate marginal coral community in Japan. Outbreaks of the disease have been observed during the summer and autumn months since 2014. It affects the coral species Porites heronensis and was tentatively named “White Mat Syndrome” (WMS) as it consists of a white microbial mat dominated by Thiothrix sp., a sulfide oxidizing bacteria. Outbreaks followed high seasonal temperatures and were associated with the macroalga Gelidium elegans, which acts as a pathogen reservoir. With ocean warming and the anticipated increase in novel coral-algae interactions as some coral species shift poleward, WMS and emerging diseases could hinder the role of temperate areas as a future coral refuge.
Show more [+] Less [-]Review: Host-pathogen dynamics of seagrass diseases under future global change
2018
Sullivan, Brooke K. | Trevathan-Tackett, Stacey M. | Neuhauser, Sigrid | Govers, Laura L.
Human-induced global change is expected to amplify the disease risk for marine biota. However, the role of disease in the rapid global decline of seagrass is largely unknown. Global change may enhance seagrass susceptibility to disease through enhanced physiological stress, while simultaneously promoting pathogen development. This review outlines the characteristics of disease-forming organisms and potential impacts of global change on three groups of known seagrass pathogens: labyrinthulids, oomycetes and Phytomyxea. We propose that hypersalinity, climate warming and eutrophication pose the greatest risk for increasing frequency of disease outbreaks in seagrasses by increasing seagrass stress and lowering seagrass resilience. In some instances, global change may also promote pathogen development. However, there is currently a paucity of information on these seagrass pathosystems. We emphasise the need to expand current research to better understand the seagrass-pathogen relationships, serving to inform predicative modelling and management of seagrass disease under future global change scenarios.
Show more [+] Less [-]Processes in Pathogenic Biocolloidal Contaminants Transport in Saturated and Unsaturated Porous Media: A Review
2011
Sen, Tushar Kanti
There are several classes of subsurface colloids, abiotic and biotic. Basically, small particles of inorganic, organic and pathogenic biocolloids variety exist in natural subsurface system. Transport of these pathogenic biocolloidal contaminants (Viruses, bacteria and protozoa) pose a great risk in water resources and have caused large outbreaks of waterborne diseases. Biocolloid transport processes through saturated and unsaturated porous media is of significant interest, from the perspective of protection of groundwater supplies from contamination, assessment of risk from pathogens in groundwater and for the design of better water treatment systems to remove biocolloids from drinking water supplies This paper has reviewed the large volume of work that has already been done and the progress that has been made towards understanding the various basic multi-processes to predicting the biocolloid transport in saturated and unsaturated porous media. There are several basic processes such as physical, chemical and biological processes which are important in biocolloid transport. The physical processes such as advection, dispersion, diffusion, straining and physical filtration, adsorption and biological processes such as growth/decay processes and include active adhesion/detachment, survival and chemotaxis are strongly affected on biocolloid transport in saturated and unsaturated porous media. The unsaturated zone may play an important role in protecting aquifers from biocolloidal contamination by retaining them in the solid phase during their transport through the zone. Finally, author here highlighted the future research direction based on his critical review on biocolloid transport in saturated and unsaturated porous media.
Show more [+] Less [-]Antibiotics, antibiotic-resistant bacteria, and resistance genes in aquaculture: risks, current concern, and future thinking
2022
Aquaculture is remarkably one of the most promising industries among the food-producing industries in the world. Aquaculture production as well as fish consumption per capita have been dramatically increasing over the past two decades. Shifting of culture method from semi-intensive to intensive technique and applying of antibiotics to control the disease outbreak are the major factors for the increasing trend of aquaculture production. Antibiotics are usually present at subtherapeutic levels in the aquaculture environment, which increases the selective pressure to the resistant bacteria and stimulates resistant gene transfer in the aquatic environment. It is now widely documented that antibiotic resistance genes and resistant bacteria are transported from the aquatic environment to the terrestrial environment and may pose adverse effects on human and animal health. However, data related to antibiotic usage and bacterial resistance in aquaculture is very limited or even absent in major aquaculture-producing countries. In particular, residual levels of antibiotics in fish and shellfish are not well documented. Recently, some of the countries have already decided the maximum residue levels (MRLs) of antibiotics in fish muscle or skin; however, many antibiotics are yet not to be decided. Therefore, an urgent universal effort needs to be taken to monitor antibiotic concentration and resistant bacteria particularly multiple antibiotic-resistant bacteria and to assess the associated risks in aquaculture. Finally, we suggest to take an initiative to make a uniform antibiotic registration process, to establish the MRLs for fish/shrimp and to ensure the use of only aquaculture antibiotics in fish and shellfish farming globally.
Show more [+] Less [-]Impact of PM10 and meteorological factors on the incidence of hand, foot, and mouth disease in female children in Ningbo, China: a spatiotemporal and time-series study
2019
Huang, Ruixue | Ning, Huacheng | He, Tianfeng | Bian, Guolin | Hu, Jianan | Xu, Guozhang
Hand, foot, and mouth disease (HFMD) is a viral illness that is considered a critical public health challenge worldwide. Previous studies have demonstrated that meteorological parameters are significantly related to the incidence of HFMD in children; however, few studies have focused only on female children. This study quantified the associations of HFMD incidence with meteorological parameters and PM₁₀ (particulate matter with an aerodynamic diameter of 10 μm) among female children. Data were collected on daily HFMD cases, meteorological variables, and PM₁₀ levels in Ningbo, China, from January 2012 to December 2016. Data were assessed using a distributed lag nonlinear model (DLNM) with Poisson distribution. A total of 59,809 female children aged 0−15 years with HFMD were enrolled. The results showed that highest relative risk (RR) of HFMD for temperature was 3 °C and the lag effect was 3 days. The highest RR for PM₁₀ was 80 mg/m³ and the lag effect was 5 days. Spatial analysis showed that female HFMD incidence was mainly concentrated in the suburban of Ningbo city indicating that female children in this area should be more paid attention on avoiding this disease outbreak. Our findings suggest that HFMD prevention strategies should focus more attention on local meteorological parameters.
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