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This study investigated the effect of angiotensin II (Ang II) on apoptosis and thioredoxin-interacting protein (TXNIP) expression in INS-1 islet cells and the underlying mechanism. INS-1 cells cultured in vitro were treated with different concentration of Ang II for different time, and the viability was measured using cell counting kit-8 (CCK-8). After treatment with 1 × 10-6 mol/L Ang II for 24 h, flow cytometry and Western blot were used to measure the cell apoptosis, and Western blot was used to analyze the protein expression of TXNIP, carbohydrate response element-binding protein (ChREBP) and angiotensin II type 1 receptor (AT1R). Real-time PCR was used to detect TXNIP and ChREBP mRNA expression. IF/ICC was used to observe the TXNIP, ChREBP and AT1R expression. The results showed that Ang II reduced cell viability and induced the expression of TXNIP in a dose- and time-dependent manner (P < 0.05, n = 6) compared with the control group. Ang II induced apoptosis and up-regulated the expression of ChREBP and AT1R (P < 0.05, n = 6). AT1R inhibitor, telmisartan (TM), blocked Ang II-induced TXNIP and ChREBP overexpression (P < 0.05, n = 6) and inhibited Ang II-induced apoptosis. Taken together, Ang II increased ChREBP activation through AT1R, which subsequently increased TXNIP expression and promoted cell apoptosis. These findings suggest a therapeutic potential of targeting TXNIP in preventing Ang II-induced INS-1 cell apoptosis in diabetes.
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Angiotensina II/farmacologia , Apoptose , Proteínas de Transporte/fisiologia , Células Secretoras de Insulina/fisiologia , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/fisiologia , Proteínas de Ciclo Celular , Linhagem Celular , Ratos , Receptor Tipo 1 de Angiotensina/fisiologia , Telmisartan/farmacologia , Regulação para CimaRESUMO
Diabetes can cause a significant increase in the expression of thioredoxin (Trx)-interacting protein (TXNIP), which binds to Trx and inhibits its activity. The present study was aimed to investigate the effect of TXNIP on proliferation of rat INS-1 islet ß cells and the underlying mechanism. TXNIP overexpressing adenovirus vectors (Ad-TXNIP-GFP and Ad-TXNIPc247s-GFP) were constructed and used to infect INS-1 cells. Ad-TXNIPc247s-GFP vector carries a mutant C247S TXNIP gene, and its expression product (TXNIPc247s) cannot attach and inhibit Trx activity. The expression of TXNIP was detected by real-time PCR and Western blot. EdU and Ki67 methods were used to detect cell proliferation. Protein phosphorylation levels of ERK and AKT were detected by Western blot. The results showed that both TXNIP and TXNIPc247s protein overexpressions inhibited the proliferation of INS-1 cells, and the former's inhibitory effect was greater. Moreover, both of the two kinds of overexpressions inhibited the phosphorylation of ERK and AKT. These results suggest that TXNIP overexpression may inhibit the proliferation of INS-1 cells through Trx-dependent and non-Trx-dependent pathways, and the mechanism involves the inhibition of ERK and AKT phosphorylation.
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Proteínas de Transporte/fisiologia , Vetores Genéticos , Células Secretoras de Insulina/citologia , Adenoviridae , Animais , Proteínas de Ciclo Celular , Linhagem Celular , Proliferação de Células , Diabetes Mellitus , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Oxirredução , Fosforilação , Proteínas Proto-Oncogênicas c-akt/fisiologia , RatosRESUMO
Increased blood plasma concentration of the sulphur amino acid homocysteine (Hcy) is considered as an independent risk factor of the neurodegenerative diseases. However, the detailed molecular mechanisms by which Hcy leads to neurotoxicity have yet to be clarified. Recent research has suggested that neurotoxicity of Hcy may involve negative regulation of neural stem cell (NSC) proliferation. In the current study, primary NSCs were isolated from neonatal rat brain hippocampus and the inhibition in cell growth was observed after exposure to l50 µM and 500 µM L-Hcy. The changes in protein expression were monitored with densitometric 2D-gel electrophoresis coupled with MALDI-TOF mass spectrometry. Proteomic analysis revealed that the expression levels of two mitochondrial proteins, cytochrome bc1 complex2 (UQCRC2, the major component of electron transport chain complex III) and aconitase (an enzyme involved in the tricarboxylic acid cycle), were decreased in Hcy treatment group, compared to control group. Protein expression was further verified by Western blot, and their enzymatic activities were also down-regulated in NSCs after Hcy treatment. Restoration of aconitase and UQCRC2 protein levels using their expression vectors could partly rescue the cell viability inhibition caused by Hcy. Moreover, Hcy caused the increase in the intracellular levels of reactive oxygen species (ROS) and the decrease in ATP content, which are known to play important roles in the cellular stress response of the cell growth. Altogether, the results suggest that the decreased expression and enzymatic activities of the mitochondrial proteins may be possible causes of the overproduction of ROS and depletion of ATP. The inhibition in cell growth at the end of Hcy treatment was probably due to the changes in protein expression and mitochondrial dysfunction in vitro cultures of NSCs.
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Proliferação de Células/efeitos dos fármacos , Homocisteína/farmacologia , Células-Tronco Neurais/citologia , Aconitato Hidratase/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Animais Recém-Nascidos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Hipocampo/citologia , Homocisteína/sangue , Proteômica , Ratos , Espécies Reativas de Oxigênio/metabolismoRESUMO
A middle-aged woman with rheumatic heart disease, mitral valve prolapse and incompletely closed mitral valve medium, patent foramen ovale, merge multiple uterine fibroids, and moderate blood loss anemia underwent mitral valve replacement surgery with total abdominal hysterectomy under general anesthesia and cardiopulmonary bypass condition. The surgery was successful, and postoperative bleeding, blood clots, heart failure, and other related complications did not occur. Heart valve replacement surgery with the surgical treatment of uterine fibroids effectively improves the safety of surgical treatment for patients as well as reduces the patient's medical expenses and risk of secondary surgery and trauma.
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Implante de Prótese de Valva Cardíaca/métodos , Histerectomia/métodos , Leiomioma/cirurgia , Prolapso da Valva Mitral/cirurgia , Neoplasias Uterinas/cirurgia , Adulto , Feminino , Seguimentos , Humanos , Leiomioma/complicações , Prolapso da Valva Mitral/complicações , Fatores de Tempo , Neoplasias Uterinas/complicaçõesRESUMO
With the development of the electric vehicle industry, the number of power batteries has increased dramatically. Establishing a recycling EOL (end-of-life) battery network for secondary use is an effective way to solve resource shortage and environmental pollution. However, existing networks are challenging due to the high uncertainty of EOL batteries, e.g., quantity and quality, resulting in a low recycling rate of the recovery network. To fill this gap, this paper proposes a stochastic programming approach for recovery network design under uncertain conditions of EOL batteries. Firstly, a multi-objective model for battery recovery network is established, considering carbon emissions and economic benefits. Secondly, a stochastic programming approach is proposed to clarify the model. Subsequently, the genetic algorithm is employed to solve the proposed model. Finally, a recovery network case of Region T is given to verify the credibility and superiority of the proposed method. The results demonstrate that the proposed model reduces carbon emissions by 20 metric tons and increases overall economic benefits by 10 million yuan in Region T compared to the deterministic model. Furthermore, the two portions affecting the optimization results are also discussed to provide a reference for reducing carbon emissions and improving economic efficiency in recycling networks.
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Chronic cutaneous wounds present a significant challenge for healthcare providers globally, with the risk of bacterial infections emerging as a particularly concerning issue. There is an increasing need to employ a combination of diverse antibacterial strategies to address infections comprehensively in chronic wounds. This study introduces a highly efficient antibacterial platform that encapsulates the NO precursor (BNN6) into ß-cyclodextrin-modified hemin-bearing polydopamine nanoparticles called NO/CHPDA. These nanoparticles are seamlessly integrated into a hydrogel composite comprised of L-arginine grafted chitosan (Arg-CS) and oxide dextrans (oDex). The amalgamation of photothermal therapy (PTT), chemodynamic therapy (CDT), and nitric oxide (NO) antibacterial strategies within the NO/CHPDA@Arg-CS/oDex nanocomposite hydrogel demonstrates a synergistic and highly effective capacity to eradicate bacteria and accelerate the wound healing process in vivo. Remarkably, this nanocomposite hydrogel maintains excellent biocompatibility and induces minimal side effects. The resulting nanocomposite hydrogel represents a promising therapeutic solution for treating bacterial infections in wound healing applications.
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Infecções Bacterianas , Quitosana , Ciclodextrinas , Indóis , Polímeros , Humanos , Nanogéis , Hemina , Antibacterianos/farmacologia , Arginina , Hidrogéis/farmacologia , Óxido NítricoRESUMO
The emergence of immune checkpoint inhibitors (ICIs) has heralded a transformative era in the therapeutic landscape of non-small cell lung cancer (NSCLC). While ICIs have demonstrated clinical efficacy in a portion of patients with NSCLC, these treatments concurrently precipitate a spectrum of immune-related adverse events (irAEs), encompassing mild to severe manifestations, collectively posing a risk of significant organ damage. Consequently, there exists an imperative to augment our comprehension of the pathophysiological underpinnings of irAEs and to formulate more efficacious preventive and ameliorative strategies. In this comprehensive review, we delineate the clinical presentation of organ-specific irAEs in patients with NSCLC and provide an in-depth analysis of recent advancements in understanding the mechanisms driving ICI-induced toxicity. Furthermore, we discuss potential strategies and targets for ameliorating these irAEs. Ultimately, this review aims to furnish valuable insights to guide further research endeavours in the context of irAEs in NSCLC patients.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Checkpoint Imunológico/efeitos adversosRESUMO
Objective: To investigate whether the increased expression of thioredoxin interacting protein (TXNIP) in diabetes affects the senescence of islet ß cells. Methods: Six normal mice (db/m) and six diabetic mice (db/db) were randomly selected. Fasting blood glucose was measured by blood sugar meter, the expression levels of TXNIP protein, p16, p21 and Rb in pancreatic tissues were detected by Western blot, senescence-associated beta-galactosidase activity in pancreatic tissue was determined by immunochemical staining. INS-1 islet beta cells were randomly divided into 7 groups (n=6), and transfected with lentiviruses (30 µl) for 4 to 6 hours, then was screened with puromycin (PM, 3 µg/m) for 7 days to construct normal group, scramble ShRNA group (interference with airborne poison group), TXNIP-ShRNA-1 group (TXNIP silence group-1), TXNIP-ShRNA-2 group (TXNIP silence group 2), TXNIP-ShRNA-3 group (TXNIP silence group 3), Ad-GFP group (overexpression of the air virus group), Ad-TXNIP-GFP group (TXNIP overexpression group) stably transferred INS-1 islet beta cell line. TXNIP protein expression was detected by Western blot, aging-related beta-galactosidase activity was detected by immunochemical staining, the changes of expression of p16, p21 and Rb was determined by Western blot. Results: Compared with normal mice, the fasting blood glucose of db/db group was increased significantly (Pï¼0. 01), the expression of TXNIP protein was increased significantly in pancreatic tissues(Pï¼0. 05), positive staining rate of ß- galactosidase was increased significantly in pancreatic tissues, p16/p21/Rb protein expression levels were increased significantly (Pï¼0. 05). Compared with Ad-GFP group, the positive staining rate of ß- galactosidase in Ad-TXNIP-GFP group was increased significantly, p16/p21/Rb protein expression levels were increased significantly (Pï¼0. 01). Compared to the scramble ShRNA group, the positive staining rate of ß- galactosidase in TXNIP-ShRNA group was decreased, p16/p21/Rb protein expression levels were decreased significantly (Pï¼0. 05). Conclusion: Diabetes can induce islet ß-cell senescence by up-regulating TXNIP expression.
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Proteínas de Transporte/metabolismo , Senescência Celular , Diabetes Mellitus Experimental , Ilhotas Pancreáticas/citologia , Tiorredoxinas/metabolismo , Animais , Proteínas de Transporte/genética , CamundongosRESUMO
Cellular events for neural progenitor cells, such as proliferation and differentiation, are regulated by multiple intrinsic and extrinsic cell signals. Folate plays central roles in central nervous system development, so folate, as an extrinsic signal, may affect neural stem cell (NSC) proliferation and differentiation. In this study, we have investigated the effect of folate on extracellular signal-regulated kinase (ERK1/2) phosphorylation, cell proliferation and apoptosis in fetal NSCs. The results showed that treatment of neurospheres with folate increased ERK1/2 phosphorylation and cell proliferation in a concentration-dependent manner. Folate also decreased the percentage of apoptotic cells. All of these effects of folate were prevented by a selective inhibitor (U0126) of mitogen-activated/ERK kinase 1/2. In conclusion, fetal NSCs respond to folate with ERKl/2 phosphorylation, cell proliferation and decreased apoptosis. This mechanism may mediate the regulation by folate of neurogenesis in the central nervous system.
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Proliferação de Células , Células-Tronco Fetais/metabolismo , Ácido Fólico/administração & dosagem , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neuroglia/metabolismo , Neurônios/metabolismo , Análise de Variância , Animais , Apoptose , Encéfalo/citologia , Encéfalo/embriologia , Encéfalo/metabolismo , Células Cultivadas , Células-Tronco Fetais/citologia , Proteínas de Filamentos Intermediários/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Nestina , Neurogênese , Neuroglia/citologia , Neurônios/citologia , Fosforilação , Ratos , Ratos Sprague-DawleyRESUMO
Cellular events for neural progenitor cells, such as proliferation and differentiation, are regulated by multiple intrinsic and extrinsic cell signals. Folate plays a central role in central nervous system development, so folate, as an extrinsic signal, may affect neural stem cell (NSC) proliferation and differentiation. In the present study, we investigated the effects of folate deficiency on the cell proliferation, cell apoptosis and homocysteine concentrations in NSCs. NSCs were isolated from fetal rats and identified as NSCs by their expression of immunoreactive nestin. Cell proliferation was quantitated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Apoptotic cells were detected and confirmed by flow cytometric analysis. We measured homocysteine concentrations in NSCs by high performance liquid chromatography and detected the expression of caspase-3 by western blot method. Folate deficiency not only decreased cell proliferation, but also increased the apoptotic rate of NSCs as demonstrated by the increased expression of early apoptotic markers such as caspase-3, compared to control group (p<0.05). Furthermore, There was a statistically significant increase in homocysteine concentration during folate deficiency in NSCs (p<0.05). These data suggest that folate affects the cell proliferation, apoptosis and homocysteine generation in NSC cells.
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The aim of the present study was to investigate the effects of phosphorylatable nucleus localization signal linked nucleic kinase substrate short peptide (pNNS)-conjugated chitosan (pNNS-CS) mediated miR-140 and IGF-1 in both rabbit chondrocytes and cartilage defects model. pNNS-CS was combined with pBudCE4.1-IGF-1, pBudCE4.1-miR-140, and negative control pBudCE4.1 to form pDNA/pNNS-CS complexes. Then these complexes were transfected into chondrocytes or injected intra-articularly into the knee joints. High levels of IGF-1 and miR-140 expression were detected both in vitro and in vivo. Compared with pBudCE4.1 group, in vitro, the transgenic groups significantly promoted chondrocyte proliferation, increased glycosaminoglycan (GAG) synthesis, and ACAN, COL2A1, and TIMP-1 levels, and reduced the levels of nitric oxide (NO), MMP-13, and ADAMTS-5. In vivo, the exogenous genes enhanced COL2A1, ACAN, and TIMP-1 expression in cartilage and reduced cartilage Mankin score and the contents of NO, IL-1ß, TNF-α, and GAG contents in synovial fluid of rabbits, MMP-13, ADAMTS-5, COL1A2, and COL10A1 levels in cartilage. Double gene combination showed better results than single gene. This study indicate that pNNS-CS is a better gene delivery vehicle in gene therapy for cartilage defects and that miR-140 combination IGF-1 transfection has better biologic effects on cartilage defects.
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Doenças das Cartilagens/tratamento farmacológico , Cartilagem Articular/efeitos dos fármacos , Quitosana/farmacologia , Condrócitos/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/metabolismo , MicroRNAs/metabolismo , Peptídeos/farmacologia , Animais , Doenças das Cartilagens/metabolismo , Cartilagem Articular/metabolismo , Condrócitos/metabolismo , Técnicas de Transferência de Genes , Humanos , Articulação do Joelho/metabolismo , Metaloproteinase 13 da Matriz/metabolismo , Óxido Nítrico/metabolismo , Coelhos , Líquido Sinovial/efeitos dos fármacos , Líquido Sinovial/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Transfecção/métodosRESUMO
OBJECTIVES: To investigate the effect of selective cyclooxygenase-2 (COX-2) inhibitor on alcohol-induced liver injury in rats. METHODS: 58 male Wistar rats were randomly divided into three groups: control group treated with dextrose and corn oil, model group with ethanol and corn oil, treatment group with corn oil and ethanol plus a selective COX-2 inhibitor celecoxib. All treatments were injected into stomach through intragastric tubes. Liver samples were analyzed for histopathology with light microscope (LM) and transmission electron microscope (TEM), and the expression of COX-2 with western blotting. Levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in serum, levels of 6-Keto-prostaglandin F1 alpha (6-k-PGF1a) and thromboxane B2 (TXB2) in liver, and activity of glutathione s-transferase (GST) both in liver tissue and in plasma were measured. RESULTS: LM and TEM indicated hepatocytes were injured obviously in the model group and slightly in the treatment group. The levels of AST and ALT in serum, TXB2 in liver and the activity of GST in plasma increased significantly in the model group (t> or =2.294, P<0.05), but the activity of GST in liver decreased significantly (t=8.856, P<0.01) compared with those in the control group. To compare with the model group, the levels of AST and TXB2 decreased significantly (t=4.305, P<0.01; t=2.799, P<0.01), meanwhile the activity of GST increased significantly (t=10.134, P<0.01) in the treatment group. COX-2 expression in liver by western blotting increased significantly in the model group, compared with the control group (t=4.067, P<0.01) and the treatment group (t=2.251, P<0.05). Exceptionally, the level of 6-k-PGF1a decreased significantly (t=2.284, P<0.05) in the model group. CONCLUSION: COX-2 has involved in the alcohol-induced liver injury, and its inhibitor can diminish alcohol-induced liver injury in rats through decreasing TXB2 level
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Inibidores de Ciclo-Oxigenase/uso terapêutico , Isoenzimas/antagonistas & inibidores , Hepatopatias Alcoólicas/prevenção & controle , Substâncias Protetoras/uso terapêutico , Animais , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Modelos Animais de Doenças , Etanol , Masculino , Prostaglandina-Endoperóxido Sintases , Ratos , Ratos Wistar , Tromboxano B2/metabolismoRESUMO
The present study investigated the effect of folic acid supplementation on the Notch signaling pathway and cell proliferation in rat embryonic neural stem cells (NSCs). The NSCs were isolated from E14-16 rat brain and grown as neurospheres in serum-free suspension culture. Individual cultures were assigned to one of 3 treatment groups that differed according to the concentration of folic acid in the medium: Control (baseline folic acid concentration of 4 mg/l), low folic acid supplementation (4 mg/l above baseline, Folate-L) and high folic acid supplementation (40 mg/l above baseline, Folate-H). NSCs were identified by their expression of immunoreactive nestin and proliferating cells by incorporation of 5'bromo-2'deoxyuridine. Cell proliferation was also assessed by methyl thiazolyl tetrazolium assay. Notch signaling was analyzed by real-time PCR and western blot analyses of the expression of Notch1 and hairy and enhancer of split 5 (Hes5). Supplementation of NSCs with folic acid increased the mRNA and protein expression levels of Notch1 and Hes5. Folic acid supplementation also stimulated NSC proliferation dose-dependently. Embryonic NSCs respond to folic acid supplementation with increased Notch signaling and cell proliferation. This mechanism may mediate the effects of folic acid supplementation on neurogenesis in the embryonic nervous system.
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OBJECTIVE: The aim of this study was to systematically evaluate the health status of Asian immigrants in Canada and the associated factors. METHODS: Using data from the 2003 Canadian Community Health Survey, a descriptive analysis was performed to estimate the frequency of health associated factors among different populations. Age-standardization rates was also used to compare the prevalence of chronic conditions among Asian immigrants, other immigrants and native residents. Logistic regression analysis was used to estimate the adjusted Odds ratio (OR) associated with each health outcome and 95% confidence interval (95% CI) after controlling for potential confounding factors. RESULTS: After age-standardization, Asian immigrants had a similar prevalence of 1-5 chronic conditions and a lower prevalence of 5+ chronic conditions (3.56%) compared with non-immigrants (5.31%). Asian immigrants were less likely to report any chronic disease (OR = 0.49, 95% CI: 0.46-0.51) than non-immigrants (OR = 1.00). Recent Asian immigrants were less likely to report any chronic condition (OR= 0.34, 95% CI: 0.31-0.37) than long-term Asian immigrants (OR = 0.62, 95% CI: 0.58-0.66). After adjusting for socioeconomic status and lifestyle factors, Asian immigrants had a slightly changed risk of four chronic conditions with exception of heart disease. CONCLUSION: Asian immigrants had lower risk of chronic conditions as a whole, however, these health advantages decreased along with increasing length of residence in Canada. Socioeconomic factors and lifestyles cannot fully explain the differences of health status between Asian immigrants and non-immigrant Canadians reported in this paper.
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Emigrantes e Imigrantes , Nível de Saúde , Inquéritos e Questionários , Adolescente , Adulto , Povo Asiático , Canadá/etnologia , Criança , Inquéritos Epidemiológicos , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Adulto JovemRESUMO
The salt content in 180 samples of concentrated animal manures collected in Jiangsu Province was analyzed and the risk of soil salinisation by the application of manures was evaluated by the methods of spatial analysis on GIS and simulating prediction on the accumulation model of salt in soil. The salt content in animal manures was high, with the highest value of 24.2 g x kg(-1) (dry weight). The risk of potential soil salinisation might exist in the coastal region such as Nantong, Yancheng, Lianyungang and the Xuhuai region such as Xuzhou, Suqian, Huaian with the application of animal manures. There was nearly no risk of salinisation by the application of animal manures on the open-field soil, but was obvious influence on the greenhouse soil, the salt content in the greenhouse soil increased by 1.0-2.5 g x kg(-1) after 65-100 t x (hm2 x a)(-1) dry animal manure with the salt content of 24.2 g x kg(-1) was applied for 2-8 a, which might cause mild, moderate or strong soil salinisation.
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Esterco/análise , Cloreto de Sódio/análise , Poluentes do Solo/análise , Solo/análise , Agricultura , Animais , Animais Domésticos , China , Fertilizantes , Aves DomésticasRESUMO
Based on the livestock statistical data of 31 provinces of 1997 - 2004, this paper analyzed the structure of livestock and the variation of fecal nitrogen pollution load in China. The results showed that the relationship between structure of livestock and the economic situation of different provinces was obviously significant. The nitrogen pollution load of livestock was increasing gradually from the northwest to the southeast, and could be divided into relative higher and lower parts, in line with the boundary of 400 mm rainfall of China. Meanwhile, in Beijing and Shanghai, with population concentrated and economy developed, the livestock had developed at a higher speed. However, in the last few years, the developing speed had been decreased slowly; the pollution load had begun to decrease, while the pollution load of livestock in the provinces around Beijing and Shanghai has been increased gradually. Additionally, it is found that only eight provinces are not facing the risk of livestock pollution theoretically.