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1.
Internet resource in Portuguese | LIS -Health Information Locator | ID: lis-48189

ABSTRACT

Um estudo liderado pelo Instituto Oswaldo Cruz (IOC/Fiocruz) identificou anticorpos contra o novo coronavírus em um gato e um cachorro de rua do Rio de Janeiro.


Subject(s)
SARS Virus/growth & development , Antibodies , Health Research Evaluation , Coronavirus Infections , Animals
2.
Sci Rep ; 11(1): 9387, 2021 04 30.
Article in English | MEDLINE | ID: mdl-33931684

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), calls for prompt and accurate diagnosis and rapid turnaround time for test results to limit transmission. Here, we evaluated two independent molecular assays, the Biomeme SARS-CoV-2 test, and the Precision Biomonitoring TripleLock SARS-CoV-2 test on a field-deployable point-of-care real-time PCR instrument, Franklin three9, in combination with Biomeme M1 Sample Prep Cartridge Kit for RNA 2.0 (M1) manual extraction system for rapid, specific, and sensitive detection of SARS-COV-2 in cell culture, human, and animal clinical samples. The Biomeme SARS-CoV-2 assay, which simultaneously detects two viral targets, the orf1ab and S genes, and the Precision Biomonitoring TripleLock SARS-CoV-2 assay that targets the 5' untranslated region (5' UTR) and the envelope (E) gene of SARS-CoV-2 were highly sensitive and detected as low as 15 SARS-CoV-2 genome copies per reaction. In addition, the two assays were specific and showed no cross-reactivity with Middle Eastern respiratory syndrome coronavirus (MERS-CoV), infectious bronchitis virus (IBV), porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis (TGE) virus, and other common human respiratory viruses and bacterial pathogens. Also, both assays were highly reproducible across different operators and instruments. When used to test animal samples, both assays equally detected SARS-CoV-2 genetic materials in the swabs from SARS-CoV-2-infected hamsters. The M1 lysis buffer completely inactivated SARS-CoV-2 within 10 min at room temperature enabling safe handling of clinical samples. Collectively, these results show that the Biomeme and Precision Biomonitoring TripleLock SARS-CoV-2 mobile testing platforms could reliably and promptly detect SARS-CoV-2 in both human and animal clinical samples in approximately an hour and can be used in remote areas or health care settings not traditionally serviced by a microbiology laboratory.


Subject(s)
/diagnosis , Real-Time Polymerase Chain Reaction/methods , /isolation & purification , Animals , Buffers , Cricetinae , Humans , Mobile Applications , Reagent Kits, Diagnostic , Sensitivity and Specificity , Time Factors
3.
Zhen Ci Yan Jiu ; 46(4): 259-65, 2021 Apr 25.
Article in Chinese | MEDLINE | ID: mdl-33931988

ABSTRACT

OBJECTIVE: To observe the effect of electroacupuncture(EA)on locomotor activity and the expression of high-mobility group box-1(HMGB1) and Toll-like receptor 4(TLR4) in mice with spinal cord injury(SCI), so as to explore its mechanisms underlying improvement of SCI at the acute stage. METHODS: Forty-eight female C57BL/6 mice were equally randomized into 3 groups: sham operation, model and EA. The SCI model was established by clamping the spinal cord with a serrefine after laminectomy at the 1st lumbar vertebra(L1). EA (1.5 Hz/7.5 Hz, 1.0 mA) was applied to "Jiaji"(EXH-B2) for 10 min, once a day for 5 and 14 days, separately. The hindlimb locomotor function was assessed by Basso, Beattie, Bresnahan Locomotor Rating Scale (BBB). Histopathological changes of the injured area of the spinal cord were determined by H.E. staining. The expression levels of spinal HMGB1, TLR4, ionized calcium binding adaptor molecule 1(Iba1) proteins were detected by Western blot, and the Iba1-positive microglial cells and HMGB1 and Iba1 co-labelled microglia were displayed by immunofluorescence staining. RESULTS: After SCI, the BBB scores on day 5 and 14 were obviously decreased (P<0.05), and the expression of HMGB1 on day 14, TLR4 on day 5 and 14, the number of Iba1-positive microglia as well as the co-expressed HMGB1/Iba1-positive microglia on day 5 and 14 were significantly increased in the model group relevant to the sham operation group (P<0.05, P<0.01). In the EA intervention group, SCI-induced reduction of BBB scores on day 5 and 14, and increases of the expression of HMGB1 and Iba1 on day 14, and TLR4 on day 5 and 14, and the number of Iba1-positive cells as well as the co-expressed HMGB1/Iba1-positive microglia on day 14 were reversed relevant to the model group (P<0.05,P<0.01). H.E. staining showed a structural disorder with lots of cavities, severe inflammatory infiltration with a large quantity of inflammatory cells, and a reduction of normal neurons in the injured spinal cord tissue in the model group, which was relatively milder, with lower activation of microglia in the EA group. CONCLUSION: EA can significantly improve locomotor function in SCI mice, which is associated with its effects in suppressing the expression of inflammatory factors such as HMGB1, TLR4, Iba1 and the over-activation of microglia.


Subject(s)
Electroacupuncture , HMGB1 Protein , Spinal Cord Injuries , Animals , Female , HMGB1 Protein/genetics , Mice , Mice, Inbred C57BL , Spinal Cord , Spinal Cord Injuries/genetics , Spinal Cord Injuries/therapy , Spine , Toll-Like Receptor 4/genetics
4.
Chin J Physiol ; 64(2): 72-79, 2021.
Article in English | MEDLINE | ID: mdl-33938817

ABSTRACT

Long-term deprivation of female sex hormones has been shown to mediate accumulation of damaged mitochondria in ventricular muscle leading to cardiovascular dysfunction. Therefore, the roles of female sex hormones in mitochondrial quality control are closely focused. In the present study, depletion of female sex hormones impairing mitochondrial autophagy in the heart was hypothesized. Cardiac mitophagy was therefore investigated in the heart of 10-week ovariectomized (OVX) and sham-operated (SHAM) rats. By using isolated mitochondria preparation, results demonstrated an increase in mitochondrial PTEN-induced kinase 1 accumulation in the sample of OVX rats indicating mitochondrial outer membrane dysfunction. However, no change in p62 and LC3-II translocation to mitochondria was observed between two groups indicating unresponsiveness of mitophagosome formation in the OVX rat heart. This loss might be resulted from significant decreases in Parkin and Bcl2l13 expression, but not Bnip3 activation. In summary, results suggest that mitochondrial abnormality in the heart after deprivation of female sex hormones could consequently be due to desensitization of mitophagy process.


Subject(s)
Mitochondria , Mitophagy , Animals , Autophagy , Female , Gonadal Steroid Hormones , Heart , Rats
5.
Chin J Physiol ; 64(2): 61-71, 2021.
Article in English | MEDLINE | ID: mdl-33938816

ABSTRACT

Clinically typical dementia Alzheimer's disease (AD) is associated with abnormal auditory processing. However, possible molecular mechanisms responsible for the auditory pathology of AD patients are not known. According to our past research findings that the thresholds of auditory brainstem response, but not distortion product otoacoustic emissions, were significantly increased in AD mice from 9 months of age and thereafter. Thus, we further explored the possible mechanism of auditory degradation of 3×Tg-AD mice in this study. Our histochemical staining evidence showed the cochlear spiral ganglion neurons (SGN), but not the cochlear hair cells, were lost significantly in the cochlea of 3×Tg-AD mice from 9 months of age and thereafter. Our immunostaining and western blotting evidence showed that phosphorylated tau protein (p-Tau), p-glycogen synthase kinase 3, neurofilament, and apoptosis-related p53, Bcl2-associated X protein, cytochrome c, caspase-9, and caspase-3 were gradually increased, but B-cell lymphoma 2 was gradually decreased with age growth in the cochlea of 3×Tg-AD mice. We suggested that tau hyperphosphorylation and p-Tau 181 aggregation, and mitochondria- and endoplasmic reticulum stress-mediated apoptosis may play a role in the degeneration of SGN in the cochlea. Progressive SGN degeneration in the cochlea may contribute to hearing loss of aging 3×Tg-AD mice.


Subject(s)
Alzheimer Disease , Hearing Loss , Animals , Apoptosis , Disease Models, Animal , Humans , Mice , Mice, Transgenic , Phosphorylation , Spiral Ganglion
6.
Chin J Physiol ; 64(2): 80-87, 2021.
Article in English | MEDLINE | ID: mdl-33938818

ABSTRACT

Ca2+-sensing receptors (CaSR), activated by elevated concentrations of extracellular Ca2+, have been known to regulate functions of thyroid cells, neurons, and endothelial cells (EC). In this report, we studied CaSR-mediated Ca2+ influx in mouse cerebral microvascular EC (bEND.3 cells). Cytosolic free Ca2+ concentration and Mn2+ influx were measured by fura-2 microfluorometry. High (3 mM) Ca2+ (CaSR agonist), 3 mM spermine (CaSR agonist), and 10 µM cinacalcet (positive allosteric modulator of CaSR) all triggered Ca2+ influx; however, spermine, unlike high Ca2+ and cinacalcet, did not promote Mn2+ influx and its response was poorly sensitive to SKF 96365, a TRP channel blocker. Consistently, 2-aminoethoxydiphenyl borate and ruthenium red (two other general TRP channel blockers) suppressed Ca2+ influx triggered by cinacalcet and high Ca2+ but not by spermine. Ca2+ influx triggered by high Ca2+, spermine, and cinacalcet was similarly suppressed by A784168, a potent and selective TRPV1 antagonist. Our results suggest that CaSR activation triggered Ca2+ influx via TRPV1 channels; intriguingly, pharmacological, and permeability properties of such Ca2+ influx depended on the stimulating ligands.


Subject(s)
Calcium Signaling , Endothelial Cells , Animals , Calcium/metabolism , Endothelial Cells/metabolism , Mice , Receptors, Calcium-Sensing/metabolism
7.
Chin J Physiol ; 64(2): 97-105, 2021.
Article in English | MEDLINE | ID: mdl-33938820

ABSTRACT

To investigate the persistence time and the effectiveness of exercise preconditioning (EP) on myocardial protection in exhausted rats from myocardial enzymes, electrocardiogram (ECG), cardiac function, and mitochondrial respiratory function after cessation of exercise training. One hundred and twelve healthy male Sprague-Dawley rats were randomly divided into seven groups (n = 16): control group (CON), exhaustive exercise (EE) group, EP group, and EE after EP (EP + EE); furthermore, EP + EE group was randomly divided into 1D, 3D, 9D, and 18D groups (1D, 3D, 9D, and 18D) and performed exhaustive treadmill exercise at a speed of 30 m/min on the 1st, 3rd, 9th, and 18th days separately after EP exercise stopped. We detected the serum contents of N-terminal pro B type natriuretic peptide (NT-proBNP) and cardiac troponin I (cTnI) by the enzyme-linked immunosorbent assays method, recorded ECG, detected heart function by pressure volume catheter, measured the respiratory rates of rat myocardial mitochondria state 3 and 4 of complex I, complex II, and IV by high-resolution breathing apparatus. EP could decrease the serum content of NT-proBNP and cTnI, improved the electrical derangement and the left ventricular function in exhausted rats. Moreover, the protective effect was more obvious in the 9th day after EP stopped, whereas it would disappear when EP stopped for more than 18 days. Compared with EE group, the respiratory rate value of myocardial mitochondrial complex increased in 1D, 3D, and 9D groups. Therefore, the protective effect of EP on the heart of exhausted rats decreased with the prolongation of stopping training time, and the effect was significant within 3 days of discontinuing training, then decreased gradually, and completely disappeared in the 18th day. EP enhanced the cardiac function in exhausted rats through raising the nicotinamide adenine diphosphate hydride (NADH) electron transport chain and increased the respiration rates of mitochondrial respiratory complex I and IV state 3, thereby improved myocardial mitochondrial respiratory function and energy metabolism.


Subject(s)
Physical Conditioning, Animal , Animals , Heart , Male , Myocardium , Rats , Rats, Sprague-Dawley , Troponin I
8.
Chin J Physiol ; 64(2): 88-96, 2021.
Article in English | MEDLINE | ID: mdl-33938819

ABSTRACT

Calcium-related ischemic injury (CRII) can damage cells of the neurovascular unit (NVU). Here, we investigate the protective effects of linalyl acetate (LA) against CRII-induced NVU damage and evaluate the underlying mechanisms. The protective effects of LA in cell lines representative of NVU components (BEND, SH-SY5Y, BV2, and U373 cells) were evaluated following exposure to oxygen-glucose deprivation/reoxygenation alone (OGD/R-only) or OGD/R in the presence of 5 mM extracellular calcium ([Ca2+]o) to mimic CRII. LA reversed damage under OGD/R-only conditions by blocking p47phox/NADPH oxidase (NOX) 2 expression, reactive oxygen species (ROS) production, nitric oxide (NO) abnormality, and lactate dehydrogenase (LDH) release only in the BEND cells. However, under CRII-mimicking conditions, LA reversed NO abnormality and matrix metalloproteinase (MMP)-9 activation in the BEND murine brain endothelial cells; inhibited p47phox expression in the human SH-SY5Y neural-like cells; decreased NOX2 expression and ROS generation in the BV2 murine microglial cells; and reduced p47phox expression in the U373 human astrocyte-like cells. Importantly, LA protected against impairment of the neural cells, astrocytes, and microglia, all of which are cellular components of the NVU induced by exposure to CRII-mimicking conditions, by reducing LDH release. We found that LA exerted a protective effect in the BEND cells that may differ from its protective effects in other NVU cell types, following OGD/R-induced damage in the context of elevated [Ca2+]o.


Subject(s)
Calcium , Endothelial Cells , Animals , Glucose , Humans , Mice , Monoterpenes , Oxygen , Reactive Oxygen Species
9.
Chin J Physiol ; 64(2): 106-114, 2021.
Article in English | MEDLINE | ID: mdl-33938821

ABSTRACT

Studies indicate that rapid weight gain at critical development stages, such as the lactation period, is associated with the development of obesity, cardiovascular diseases, and diabetes in the long term. In addition to metabolic changes during adulthood, overweight/obesity may influence reproductive function. Human and animal studies suggest that lifestyle changes through exercise and/or controlled diet result in improved semen quality in obese individuals. However, the relationship between exercise volume/intensity and reproductive capacity effects remains inconclusive. The present study aimed to evaluate the effects of moderate intensity endurance training and high-intensity interval training (HIIT) on the reproductive parameters of lactating overfed male Wistar rats. Postnatal overfeeding was induced by applying the litter size reduction method. Forty males Wistar rats were used, divided into four groups: one with control litters (CLs) (10 animals/litter-sedentary) and three with small litters (SLs) (4 animals/litter), divided into sedentary, moderate endurance training, and HIIT. Morphologic, metabolic, and reproductive variables were analyzed. SL sedentary group showed increased body weight, adiposity, and decreased relative weight of the seminal vesicle, prostate, and epididymis as well as changes in the insulin tolerance and oral glucose tolerance tests glycemic tests compared to CL sedentary group. Endurance and HIIT protocols were efficient in improving the glycemic metabolism, central fat accumulation of trained groups and did not affect reproductive parameters. Endurance and HIIT protocols proved to be effective in reversing these metabolic changes without impairing the evaluated reproductive parameters.


Subject(s)
Endurance Training , High-Intensity Interval Training , Adult , Animals , Female , Humans , Lactation , Male , Rats , Rats, Wistar , Semen Analysis
10.
J Anim Sci ; 99(5)2021 May 01.
Article in English | MEDLINE | ID: mdl-33939812

ABSTRACT

Automatic feeding systems in pig production allow for the recording of individual feeding behavior traits, which might be influenced by the social interactions among individuals. This study fitted mixed models to estimate the direct and social effects on visit duration at the feeder of group-housed pigs. The dataset included 74,413 records of each visit duration time (min) event at the automatic feeder from 135 pigs housed in 14 pens. The sequence of visits at the feeder was employed as a proxy for the social interaction between individuals. To estimate animal effects, the direct effect was apportioned to the animal feeding (feeding pig), and the social effect was apportioned to the animal that entered the feeder immediately after the feeding pig left the feeding station (follower). The data were divided into two subsets: "non-immediate replacement" time (NIRT, N = 6,256), where the follower pig occupied the feeder at least 600 s after the feeding pig left the feeder, and "immediate replacement" time (IRT, N = 58,255), where the elapsed time between replacements was less than or equal to 60 s. The marginal posterior distribution of the parameters was obtained by Bayesian method. Using the IRT subset, the posterior mean of the proportion of variance explained by the direct effect (PrpσTemefos) was 18% for all models. The proportion of variance explained by the follower social effect (Prpσ^f2) was 2%, and the residual variance (σ^e2) decreased, suggesting an improved model fit by including the follower effect. Fitting the models with the NIRT subset, the estimate of PrpσTemefos was 20% but the Prpσ^f2 was almost zero and σ^e2 was identical for all models. For the IRT subset, the predicted best linear unbiased predictor (BLUP) of direct (Direct BLUP) and social (Follower BLUP) random effects on visit duration at the feeder of an animal was calculated. Feeder visit duration time was not correlated with traits, such as weight gain or average feed intake (P > 0.05), whereas for the daily feeder occupation time, the estimated correlation was positive with the Direct BLUP (r^ = 0.51, P < 0.05) and negative with the Follower BLUP (r^= -0.26, P < 0.05). The results suggest that the visit duration of an animal at the single-space feeder was influenced by both direct and social effects when the replacement time between visits was less than 1 min. Finally, animals that spent a longer time per day at the feeder seemed to do so by shortening the meal length of the preceding individual at the feeder.


Subject(s)
Eating , Feeding Behavior , Animal Feed/analysis , Animals , Bayes Theorem , Swine , Weight Gain
11.
J Anim Sci ; 99(5)2021 May 01.
Article in English | MEDLINE | ID: mdl-33939813

ABSTRACT

An enriched environment is widely used to improve domestic animals' welfare and promote their natural behaviors. Music can reduce abnormal behavior in humans, nonhuman primates, and rodents. However, little is known about the effects of music on pigs. This study aims to explore the effects of repeated music stimulation on the behavior, physiology, and immunity of growing pigs. A total of 72 hybrid piglets (Large White × Duroc × Minpig) were randomly divided into three groups, including music (Mozart K.448, 60 to 70 dB), noise (recorded mechanical noise, 80 to 85 dB), and control (natural background sound, <40 dB), and 6 h sound stimulation was given per day (1000 to 1600 hours) from 40 to 100 d of age. The behavioral activities of the pigs were observed during the music stimulation, and their serum cortisol, salivary cortisol, and serum immune indices were also measured. Compared with the control group, the music group and noise group increased activity but decreased lying of pigs (P < 0.05). A significant increase in tail-wagging, playing, and exploring behaviors of pigs was found in the music group (P < 0.05), and the noise significantly increased the aggressive behavior of the pigs (P < 0.05). Tail-wagging, playing, exploring, manipulating, and aggressive behaviors decreased over time. Short-term (8 d) music stimulus had a lower cortisol level than that of the noise and control groups (P < 0.05), whereas long-term (60 d) music stimulus increased immunoglobulin G (IgG), interleukin-2 (IL-2), and interferon-gamma (IFN-γ) levels (P < 0.05) and decreased interleukin-4 (IL-4) level (P < 0.05). Long-term noise stimulus significantly reduced the level of IgG (P < 0.05) but did not affect the level of IL-2, IL-4, and IFN-γ levels (P > 0.05). In conclusion, short-term music stimulus (8 d) reduced the stress response, whereas long-term music stimulus (60 d) enhanced the immune responses. In addition, the noise increased the aggressive behavior, and long-term noise reduced the immunity of the growing pigs.


Subject(s)
Music , Aggression , Animals , Hydrocortisone , Noise/adverse effects , Swine , Tail
12.
Am J Dent ; 34(2): 105-109, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33940669

ABSTRACT

PURPOSE: To evaluate the chemical composition and morphological properties of eroded dentin after biomodification with phosphorylated chitosan (P-Chi) and carbodiimide (EDC). METHODS: 42 bovine dentin specimens were used; 21 of these specimens were subjected to erosive challenge with 0.3% citric acid (pH = 3.2) for 2 hours. The specimens were randomly divided into six groups according to dentin substrate (sound or eroded) and biomodification [with 2.5% P-Chi, with 0.5 mol/L EDC, or no biomodification (control)]. The specimens were analyzed by Fourier-transform infrared spectroscopy (FTIR, n= 5, in triplicate) and atomic force microscopy (AFM, n= 2) to verify the phosphate, carbonate, and organic matrix absorption peaks and to investigate surface morphology, respectively. The data were analyzed with Origin 6.0. RESULTS: Dentin erosion reduced the intensity of the phosphate (1,100 cm⁻¹) and carbonate (872 cm⁻¹) related bands, which evidenced demineralization. Eroded dentin consisted of a more irregular surface containing slightly more open tubules. Modification with P-Chi removed intertubular dentin, which was compatible with surface demineralization; however, this modification obliterated dentin tubules. EDC did not promote demineralization. Biomodified dentin had a more irregular surface, irrespective of substrate type. CLINICAL SIGNIFICANCE: Eroded dentin demineralization promoted by biomodification with 2.5% phosphorylated chitosan (P-Chi) is a promising indicator for further studies and highlights the dentin intrinsic characteristics. From the point of view of dentin surface chemical analysis, more studies with P-Chi should be conducted to achieve greater interactions with surfaces and to improve the adhesive interface.


Subject(s)
Carbodiimides , Chitosan , Animals , Cattle , Dental Cements , Dentin
13.
Sci Total Environ ; 773: 144757, 2021 Jun 15.
Article in English | MEDLINE | ID: mdl-33940701

ABSTRACT

The Clinch River watershed of the upper Tennessee River Basin of Virginia and Tennessee, USA supports one of North America's greatest concentrations of freshwater biodiversity, including 46 extant species of native freshwater mussels (Order Unionida), 20 of which are protected as federally endangered. Despite the global biological significance of the Clinch River, mussel populations are declining in some reaches, both in species richness and abundance. The aim of this study was to evaluate the exposure of adult resident mussels to a suite of inorganic and organic contaminant stressors in distinct sections of the Clinch River that encompassed a range of mussel abundance and health. To provide insight into the potential role of pollutants in the decline of mussels, including within a previously documented "zone of mussel decline", the mainstem Clinch River (8 sites) and its tributaries (4 sites) were examined over two consecutive years. We quantified and related metals and organic contaminant concentrations in mussels to their associated habitat compartments (bed sediment, suspended particulate sediment, pore water, and surface water). We found that concentrations of organic contaminants in resident mussels, particularly the suite of 42 polycyclic aromatic hydrocarbons (PAHs) analyzed, were related to PAH concentrations in all four habitat (media) compartments. Further, PAH concentrations in mussel tissue (range 37.8-978.1 ng/g dry weight in 2012 and 194.3-1073.7 ng/g dry weight in 2013) were negatively related to the spatial pattern in mussel densities (rs = -0.64, p ≤ 0.05 in 2012 and rs = -0.83, p ≤ 0.05 in 2013) within the river, and were highest in the "zone of mussel decline". In contrast, the suite of 22 metals analyzed in resident mussels were largely unrelated to the spatial pattern of variation of metals in the four habitat compartments except for Manganese (Mn; range 3630.5-23,749.2 µg/g dry weight in 2012 and 1540.4-12,605.8 µg/g dry weight in 2013) in surface water (rs = 0.58, p < 0.1) and pore water (rs = 0.76, p ≤ 0.05). This study revealed that PAHs and Mn are important pollutant stressors to mussels in the Clinch River and that they are largely being delivered through the Guest River tributary watershed. Accordingly, future conservation and management efforts would benefit by identifying, and ideally mitigating, the sources of PAHs, Mn, and other current or legacy mining-associated pollutants to the mainstem river and its tributaries.


Subject(s)
Bivalvia , Environmental Pollutants , Water Pollutants, Chemical , Animals , Biodiversity , Environmental Monitoring , Fresh Water , Tennessee , Virginia , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity
14.
Sci Total Environ ; 773: 145061, 2021 Jun 15.
Article in English | MEDLINE | ID: mdl-33940713

ABSTRACT

Few studies have addressed how the diversity of basal resources change with stream regulation and the potential consequences on river biota. We sampled invertebrates above and below a series of dams, over two years, at both downwelling and upwelling zones. In each zone, we recorded the daily temperature and flow variations, estimated the algal development, measured the available resources, and analysed carbon and nitrogen stable isotope compositions of the invertebrate community. The number of hydrological pulses were typically higher below the dams than above the dams especially during high-flow periods whereas the groundwater outlets had minor effects on invertebrate assemblages. Invertebrate abundance, richness and diversity tended to decrease below the dams. Co-inertia analysis showed that flow and temperature variations, and eutrophication explained most of the variance in the invertebrate assemblages, which comprised a higher number of resilient taxa below than above the dams. The proportions of pesticide-sensitive invertebrates were lower below the dams and ovoviviparous and more generalist taxa were prominent. We did not observe the expected CPOM decrease and FPOM increase downstream. Accordingly, the proportions of each functional feeding group were remarkably similar above and below the dams despite the long distance between the sectors (>100 kms). The diversity of basal resources used within assemblages progressively increased downstream above dams. In contrast, the diversity of resources used by organisms below the dams decreased from upstream to downstream suggesting a significant influence of flow regulation on aquatic food webs. Finally, the shorter trophic chains for the invertebrate assemblages below the dams suggests that the effects of stream regulation and eutrophication induced a simplification of food webs. To our knowledge, this study is the first to connect taxonomic and functional trait changes in response to multiple stressors with the associated modifications in isotopic niches within aquatic invertebrate assemblages. CONTEXT: Understanding how stream regulation and associated anthropogenic pressures act on aquatic assemblages and trophic niches is necessary to guide management actions. GOAL: We aimed to investigate the functional responses (traits and trophic niches) of aquatic invertebrate assemblages to stream regulation and eutrophication. METHODS: We used univariate and multivariate analyses to compare the invertebrate assemblages above and below the dams and to assess the contributions of hydrology (including groundwater supplies to the river), temperature and eutrophication to the variability in the composition of invertebrate assemblages. We also considered the relative utilization of a selected set of traits describing invertebrate resilience, resistance and specialization to address the potential functional effects of stream regulation on invertebrate assemblages. Finally, carbon and nitrogen isotope analyses allowed us to characterize the length and width of invertebrate assemblage food webs as related to the availability and diversity of basal resources. RESULTS: Invertebrate abundance and richness generally decreased below the dams, with the highest impacts on insect taxa. Co-inertia analysis showed that stream regulation and eutrophication were main drivers of the aquatic invertebrate assemblages. The analysis separated the sites above and below the dams according to flow and temperature variation, whereas eutrophication appeared as a secondary stressor that separated the sites within each sector. Furthermore, the series of dams resulted in (i) a higher proportion of resilient (e.g., multivoltine) and resistant (ovoviviparous) taxa and a majority of generalists in assemblages below dams, (ii) an impact on the classical dynamics of CPOM (decrease) and FPOM (increase) sources from upstream to downstream, and (iii) a reduction in the diversity of resource use and in the trophic chain length of invertebrate assemblages below dams. The cooler and less oxygenated upwelling zones had lower invertebrate abundance; however, contrary to our expectation, the variation in the groundwater supply did not affect the composition of epigean invertebrate assemblages. CONCLUSION: This study provides insights about the impacts of flow regime alteration and eutrophication on food webs that may have been caused by regulation of permanent streams. To our knowledge, this is the first to connect taxonomic and functional trait changes in response to multiple stressors with the associated modifications in energy fluxes in aquatic invertebrate assemblages. This study suggests that bed stability, which is associated with a reduction in channel mobility below the dams and with moderate eutrophication, may provide the shelter and resources that can locally favour invertebrate assemblage dynamics and lessen the effects of flow regulation. In addition, the study suggests that the biological trait-based approach and isotope analysis are complementary approaches for addressing ecosystem functioning. The relative utilization of traits indicates the functional potential of aquatic invertebrate assemblages to face multiple stressors whereas isotope analysis is an expression of the actual effect of the stressors on the trophic structure of aquatic invertebrate assemblages.


Subject(s)
Ecosystem , Invertebrates , Animals , Food Chain , Hydrology , Rivers
15.
Sci Total Environ ; 773: 145078, 2021 Jun 15.
Article in English | MEDLINE | ID: mdl-33940715

ABSTRACT

Nanomaterials are increasingly used in food processing, daily necessities and other fields due to their excellent properties, and increase the environmental contamination. Human beings will inevitably come into contact with these nanomaterials through multiple exposure routes especially oral exposure. The intestine is an important organ for nutrient absorption and physiologic barrier, which may be the main target of nanoparticles (NPs) exposure. However, for a long time, research on the toxicity of NPs has mainly focused on organs such as liver, kidney and brain. There are few assessment data over the intestinal safety. Recently, as reported, NPs can be translocated to the intestinal part in mammals and would be distributed in different substructures of intestines, thus causing damage to the structure and function of the intestine, in which the gut microbiota and its metabolites play important roles. In addition, due to the special physiological environment of gut, nanomaterials will undergo complex transformations that may cause different biological effects from their original form. Therefore, this review aims to assess the potential adverse effects of NPs on intestine and its possible mechanisms through the results of in vivo mammalian experiments. In addition, the exposure pathway, biodistribution and biotransformation of NPs in the intestine are also considered. We hope this review will arouse people's attention to the intestinal nanotoxicology and provide basic information for further related studies.


Subject(s)
Gastrointestinal Microbiome , Nanoparticles , Animals , Humans , Liver/metabolism , Mammals , Nanoparticles/toxicity , Tissue Distribution
16.
Sci Total Environ ; 773: 145152, 2021 Jun 15.
Article in English | MEDLINE | ID: mdl-33940720

ABSTRACT

In the recent decades, the role of wastewater treatment plants has been entrenched for the dissemination of antibiotic resistant bacteria into the environment. The present study explores the dynamics of earthworms-microorganisms interactions involved in the high treatment efficacy of vermifiltration technology along with reduction of antibiotic resistant bacteria (ARB). This study is the first of its kind to investigate the performance efficacy of vermifilter (VF) for clinical laboratory wastewater treatment. The results of the study showed that earthworms and VF associated microbial community had a significant effect on Biochemical Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) reduction (78-85%), coliforms and pathogen removal (>99.9%) and caused a significant shift in the prevalence pattern of ARB. Molecular profiling of resistance causing genes such as ESBL (blaSHV, blaTEM and blaCTX-M), MRSA (mec-A) and Colistin (mcr-1) confirmed the probable mechanisms behind the resistance pattern. The microbial community diversity in the influent, earthworm's coelomic fluid and gut and filter media layers associated with the VF assists in the formation of biofilm, which helps in the removal of pathogens from the wastewater. This biofilm formation further results in a paradigm shift in the resistance profile of ARB and ARG, specifically most effective against drugs, targeting cell wall and protein synthesis inhibition such as Ampicillin, Ticarcillin, Gentamicin and Chloramphenicol. These findings further validate vermifiltration technology as a sustainable and natural treatment technology for clinical laboratory wastewater, specifically for the removal of pathogens and antibiotic resistance.


Subject(s)
Oligochaeta , Water Purification , Angiotensin Receptor Antagonists , Angiotensin-Converting Enzyme Inhibitors , Animals , Anti-Bacterial Agents/pharmacology , Bacteria/genetics , Laboratories , Oligochaeta/genetics
17.
Sci Total Environ ; 773: 145351, 2021 Jun 15.
Article in English | MEDLINE | ID: mdl-33940724

ABSTRACT

Cabled observatories are marine infrastructures equipped with biogeochemical and oceanographic sensors as well as High-Definition video and audio equipment, hence providing unprecedented opportunities to study marine biotic and abiotic components. Additionally, non-invasive monitoring approaches such as environmental DNA (eDNA) metabarcoding have further enhanced the ability to characterize marine life. Although the use of non-invasive tools beholds great potential for the sustainable monitoring of biodiversity and declining natural resources, such techniques are rarely used in parallel and understanding their limitations is challenging. Thus, this study combined Underwater Video (UV) with eDNA metabarcoding data to produce marine fish community profiles over a 2 months period in situ at a cabled observatory in the northeast Atlantic (SmartBay Ireland). By combining both approaches, an increased number of fish could be identified to the species level (total of 22 species), including ecologically and economically important species such as Atlantic cod, whiting, mackerel and monkfish. The eDNA approach alone successfully identified a higher number of species (59%) compared to the UV approach (18%), whereby 23% of species were detected by both methods. The parallel implementation of point collection eDNA and time series UV data not only confirmed expectations of the corroborative effect of using multiple disciplines in fish community composition, but also enabled the assessment of limitations intrinsic to each technique including the identification of false-negative detections in one sampling technology relative to the other. This work showcased the usefulness of cabled observatories as key platforms for in situ empirical assessment of both challenges and prospects of novel technologies in aid to future monitoring of marine life.


Subject(s)
Environmental DNA , Animals , DNA Barcoding, Taxonomic , Environmental Monitoring , Fishes/genetics , Ireland
18.
Sci Total Environ ; 773: 145442, 2021 Jun 15.
Article in English | MEDLINE | ID: mdl-33940727

ABSTRACT

Cadmium (Cd) has been confirmed as an environmental contaminant, which potential threats health impacts to humans and animals. Selenium (Se) as a beneficial element that alleviates the negative effects of Cd toxicity. Se mainly exists in two forms in food nutrients including organic Se usually as (Se-enriched yeast (SeY)) and inorganic Se (sodium selenite (SSe)). Nanoparticle of Se (Nano-Se), a new form Se, which is synthesized by the bioreduction of Se species, which attracted significant attention recently. However, compared the superiority alleviation effects of Nano-Se, SeY or SSe on Cd-induced toxicity and related mechanisms are still poorly understood. The purpose of this study was to compare the superiority antagonism effects of Nano-Se, SeY and SSe on Cd-induced inflammation response via NF-kB/IκB pathway in the heart. The present study demonstrated that exposed to Cd obviously increased the accumulation of Cd, disruption of ion homeostasis and depressed the ratios of K+/Na+ and Mg2+/Ca2+ via ion chromatography mass spectrometry (ICP-MS) detecting the heart specimens. In the results of histological and ultrastructure observation, typical inflammatory infiltrate characteristics and mitochondria and nuclear structure alterations in the hearts of Cd group were confirmed. Cd treatment enhanced the inducible nitric oxide synthase (iNOS) activities and NOS isoforms expression via NF-kB/IκB pathway to promote inflammation response. However, the combined treatment of Cd-exposed animals with Nano-Se was more effective than SeY and SSe in reversing Cd-induced histopathological changes and iNOS activities increased, reducing Cd accumulation and antagonizing Cd-triggered inflammation response via NF-kB/IκB pathway in chicken hearts. Overall, Se applications, especially Nano-Se, can be most efficiently used for relieving cardiotoxicity by exposed to Cd compared to other Se compound.


Subject(s)
Nanoparticles , Selenium , Animals , Cadmium/toxicity , Humans , Inflammation/chemically induced , NF-kappa B , Nanoparticles/toxicity , Saccharomyces cerevisiae , Sodium Selenite
19.
Sci Total Environ ; 773: 145536, 2021 Jun 15.
Article in English | MEDLINE | ID: mdl-33940730

ABSTRACT

Plastic pollution is a contaminant of global concern, as it is present even in remote ecosystems - like the Arctic. Arctic seabirds are vulnerable to ingesting plastic pollution, and these ingested particles are shed in the form of microplastics via guano. This suggests that Arctic seabird guano may act as a vector for the movement of microplastics into and around northern ecosystems. While contaminant-laden guano deposition patterns create a clear concentration gradient of chemicals around seabird colonies, this has not yet been investigated with plastic pollution. Here we tested whether a contaminant gradient of plastic pollution exists around a seabird colony that is primarily comprised of northern fulmars (Fulmarus glacialis) in the Canadian Arctic. Atmospheric deposition, surface water, and surface sediment samples were collected below the cliff-side of the colony and at increasing intervals of 1 km from the colony. Fulmars were also collected when foraging away from their colony. Microplastics and other anthropogenic microparticles were identified in all three environmental matrices as well as fulmar guano. Fibers were the most common shape in fulmar guano, atmospheric deposition and surface sediment, and fragments were the most common shape in surface water. We did not find a gradient of microplastic concentrations in environmental matrices related to distance from the colony. Combined, these results suggest that fulmars are not the primary source of microplastic around this colony. Further research is warranted to understand sources of microplastics to the areas around the colonies, including to what extent seabirds transport and concentrate microplastics in Arctic ecosystems, and whether concentrations proximate to large colonies may be species dependent.


Subject(s)
Microplastics , Plastics , Animals , Arctic Regions , Birds , Canada , Ecosystem , Environmental Monitoring
20.
Sci Total Environ ; 773: 145573, 2021 Jun 15.
Article in English | MEDLINE | ID: mdl-33940733

ABSTRACT

In Colombia, the beef production chain accounts for approximately 11.6 million cattle heads and annually produces 933 million kg of the beef carcass. There are no life cycle assessment (LCA) studies that have evaluated the environmental performance of Colombian beef systems. The present study aimed to estimate the carbon footprint (CF), non-renewable energy use, and land use of 251 cow-calf and 275 fattening farms in Colombia. The study also aimed to identify the main hotspots of adverse environmental impacts and propose possible mitigation options and their cost-effectiveness. The impact categories were estimated using the 2006 IPCC and the 2019 Refinement to 2006 IPCC guidelines, databases, and locally estimated emission factors. The functional units used were 1 kg fat and protein corrected milk (FPCM) and 1 kg live weight gain (LWG), leaving the farm gate. Three methods of allocating environmental burdens to meat and milk products were applied: economic, energy, and mass allocation. The adoption of improved pastures was considered a mitigation measure, and an economic assessment was performed to estimate the relative cost-effectiveness of its establishment. A principal component multivariate analysis and a Hierarchical Clustering on Principal Components were performed. The economic allocation method assigned a greater environmental burden to meat (83%), followed by energy content (80%) and mass production (73%). The largest sources of GHG emissions were enteric fermentation and manure deposited on pasture. Both cow-calf and fattening systems had a cluster of farms with better productivity, pasture and cattle management practices, and environmental performance. The CF for meat could be reduced by 33 to 56% for cow-calf and 21 to 25% for fattening farms, by adopting improved pastures. Therefore, our results suggest that GHG emissions can be reduced by adopting improved pastures, better agricultural management practices, efficient fertilizer usage, using the optimal stocking rate, and increasing productivity.


Subject(s)
Carbon Footprint , Dairying , Animals , Cattle , Colombia , Female , Life Cycle Stages , Milk
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