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Structural damage of Ni-rich layered oxide cathodes such as LiNi0.8Co0.1Mn0.1O2 (NCM811) and serious interfacial side reactions and physical contact failures with sulfide electrolytes (SEs) are the main obstacles restricting ≥4.6 V high-voltage cyclability of all-solid-state lithium batteries (ASSLBs). To tackle this constraint, here, a modified NCM811 with Li3PO4 coating and B/P co-doping using inexpensive BPO4 as raw materials via the one-step in situ synthesis process is presented. Phosphates have good electrochemical stability and contain the same anion (O2-) and cation (P5+) as in cathode and SEs, respectively, thus Li3PO4 coating precludes interfacial anion exchange, lessening side reactivity. Based on the high bond energy of BâO and PâO, the lattice O and crystal texture of NCM811 can be stabilized by B3+/P5+ co-doping, thereby suppressing microcracks during high-voltage cycling. Therefore, when tested in combination with LiâIn anode and Li6PS5Cl solid electrolytes (LPSCl), the modified NCM811 exhibits extraordinary performance, with 200.36 mAh g-1 initial discharge capacity (4.6 V), cycling 2300 cycles with decay rate as low as 0.01% per cycle (1C), and 208.26 mAh g-1 initial discharge capacity (4.8 V), cycling 1986 cycles with 0.02% per cycle decay rate. Simultaneously, it also has remarkable electrochemical abilities at both -20 °C and 60 °C.
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BACKGROUND: Leadless pacemakers are a recent technological advancement. It has many advantages, but there are still a few serious complications. CASE PRESENTATION: This article reports the case of a patient with an endocardial tear and dissection caused by contact with the tip of the Micra cup during surgery and summarises the relevant data. CONCLUSIONS: This case report details the occurrence and management of the incident and provides some guidance for future clinical management.
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Marca-Passo Artificial , Humanos , Resultado do Tratamento , Desenho de EquipamentoRESUMO
PURPOSE: Variability in necrosis patterns and operative techniques in surgical necrotizing enterocolitis (NEC) necessitates a standardized classification system for consistent assessment and comparison. This study introduces a novel intraoperative reporting system for surgical NEC, focusing on reliability and reproducibility. METHODS: Analyzing surgical NEC cases from January 2018 to June 2023 at two tertiary neonatal and pediatric surgery units, a new classification system incorporating anatomical details and intestinal involvement extent was developed. Its reproducibility was quantified using kappa coefficients (κ) for interobserver and intraobserver reliability, assessed by four specialists. Furthermore, following surgery, the occurrence of mortality and enteric autonomy were evaluated on the basis of surgical decision-making of the novel intraoperative classification system for surgical NEC. RESULTS: In total, 95 patients with surgical NEC were included in this analysis. The mean κ value of the intra-observer reliability was 0.889 (range, 0.790-0.941) for the new classification, indicating excellent agreement and the inter-observer reliability was 0.806 (range, 0.718-0.883), indicating substantial agreement. CONCLUSION: The introduced classification system for surgical NEC shows high reliability, deepening the understanding of NEC's intraoperative exploration aspects. It promises to indicate operative strategies, enhance prognosis prediction, and substantially facilitate scholarly communication in pediatric surgery. Importantly, it explores the potential for a standardized report and may represent a step forward in classifying surgical NEC, if pediatric surgeons are open to change.
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Enterocolite Necrosante , Especialidades Cirúrgicas , Criança , Humanos , Recém-Nascido , Laparotomia , Reprodutibilidade dos Testes , Enterocolite Necrosante/cirurgia , NecroseRESUMO
PURPOSE: Surgical necrotizing enterocolitis (NEC) is a severe medical condition that, even after surgery, a portion of the survival infants may still have neurological sequelae. The objective of this study was to identify the risk factors associated with the development of permanent neurodevelopmental impairment (NDI) in neonates with surgical NEC. METHODS: Between January 2016 and June 2022, a retrospective data collection was conducted on 98 individuals who experienced surgical NEC with gestational age ≥ 28 weeks. Among these patients, 27 patients were diagnosed with NDI, while the remaining 71 patients did not have NDI. Based on this division, the patients were categorized into the NDI group and the Non-NDI group. Demographics, comorbidities, and admission lab results were analyzed using univariate and logistic regression analyses. RESULTS: Of the 98 neonates following surgical NEC, 27(27.6%) developed permanent neurodevelopmental impairment (NDI). Predictors of NDI were identified through the final multivariable logistic regression analysis, which revealed that gestational age ≤ 32 weeks (p = 0.032; odds ratio [OR], 5.673), assisted mechanical ventilation after NEC onset (p = 0.047; OR, 5.299), postoperative acute kidney injury (p = 0.040; OR, 5.106), CRP day 3 after NEC onset (p = 0.049; OR, 1.037), time from presentation to surgery (p = 0.003; OR, 1.047) were significant risk factors. CONCLUSIONS: Our study identified gestational age ≤ 32 weeks, assisted mechanical ventilation after NEC onset, postoperative acute kidney injury, CRP day 3 after NEC onset, and time from presentation to surgery as significant risk factors for NDI in neonates with surgical NEC. These factors would be helpful to refine treatment modalities for better disease outcomes. We also determined the cut-off values of CRP day 3 after NEC onset and time from presentation to surgery, allowing for the individualized evaluation of NDI risk and the implementation of earlier targeted laparotomy.
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Injúria Renal Aguda , Enterocolite Necrosante , Doenças Fetais , Doenças do Recém-Nascido , Lactente , Feminino , Recém-Nascido , Humanos , Estudos Retrospectivos , Idade Gestacional , Enterocolite Necrosante/epidemiologia , Enterocolite Necrosante/cirurgia , Fatores de RiscoRESUMO
Parkinson's disease is presently thought to have its molecular roots in the alteration of PINK1-mediated mitophagy and mitochondrial dynamics. Finding new suppressors of the pathway is essential for developing cutting-edge treatment approaches. Our study shows that FUNDC1 suppressed PINK1 mutant phenotypes in Drosophila. The restoration of PINK1-deficient phenotypes through FUNDC1 is not reliant on its LC3-binding motif Y (18)L (21) or autophagy-related pathway. Moreover, the absence of Drp1 affects the phenotypic restoration of PINK1 mediated by FUNDC1 in flies. In summary, our findings have unveiled a fresh mechanism through which FUNDC1 compensates for the loss of PINK1, operating independently of autophagy but exerting its influence via interaction with Drp1.
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Proteínas de Drosophila , Dinâmica Mitocondrial , Animais , Dinâmica Mitocondrial/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Mitofagia/genética , Autofagia/genética , Drosophila/genética , Drosophila/metabolismo , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Drosophila/genéticaRESUMO
BACKGROUND: Seagrasses are a polyphyletic group of monocotyledonous angiosperms that have evolved to live entirely submerged in marine waters. Thus, these species are ideal for studying plant adaptation to marine environments. Herein, we sequenced the chloroplast (cp) genomes of two seagrass species (Zostera muelleri and Halophila ovalis) and performed a comparative analysis of them with 10 previously published seagrasses, resulting in various novel findings. RESULTS: The cp genomes of the seagrasses ranged in size from 143,877 bp (Zostera marina) to 178,261 bp (Thalassia hemprichii), and also varied in size among different families in the following order: Hydrocharitaceae > Cymodoceaceae > Ruppiaceae > Zosteraceae. The length differences between families were mainly related to the expansion and contraction of the IR region. In addition, we screened out 2,751 simple sequence repeats and 1,757 long repeat sequence types in the cp genome sequences of the 12 seagrass species, ultimately finding seven hot spots in coding regions. Interestingly, we found nine genes with positive selection sites, including two ATP subunit genes (atpA and atpF), three ribosome subunit genes (rps4, rps7, and rpl20), one photosystem subunit gene (psbH), and the ycf2, accD, and rbcL genes. These gene regions may have played critical roles in the adaptation of seagrasses to diverse environments. In addition, phylogenetic analysis strongly supported the division of the 12 seagrass species into four previously recognized major clades. Finally, the divergence time of the seagrasses inferred from the cp genome sequences was generally consistent with previous studies. CONCLUSIONS: In this study, we compared chloroplast genomes from 12 seagrass species, covering the main phylogenetic clades. Our findings will provide valuable genetic data for research into the taxonomy, phylogeny, and species evolution of seagrasses.
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Alismatales , Genoma de Cloroplastos , Hydrocharitaceae , Zosteraceae , Filogenia , Alismatales/genética , Zosteraceae/genética , Hydrocharitaceae/genética , Cloroplastos/genética , Genômica , Evolução MolecularRESUMO
BACKGROUND: Seagrasses are higher marine flowering plants that evolved from terrestrial plants, but returned to the sea during the early evolution of monocotyledons through several separate lineages. Thus, they become a good model for studying the adaptation of plants to the marine environment. Sequencing of the mitochondrial (mt) genome of seagrasses is essential for understanding their evolutionary characteristics. RESULTS: In this study, we sequenced the mt genome of two endangered seagrasses (Zostera japonica and Phyllospadix iwatensis). These data and data on previously sequenced mt genomes from monocotyledons provide new evolutionary evidence of genome size reduction, gene loss, and adaptive evolution in seagrasses. The mt genomes of Z. japonica and P. iwatensis are circular. The sizes of the three seagrasses (including Zostera marine) that have been sequenced to date are smaller than that of other monocotyledons. Additionally, we found a large number of repeat sequences in seagrasses. The most abundant long repeat sequences were 31-40 bp repeats. Our study also found that seagrass species lost extensive ribosomal protein genes during evolution. The rps7 gene and the rpl16 gene of P. iwatensis are exceptions to this trend. The phylogenetic analysis based on the mt genome strongly supports the previous results. Furthermore, we identified five positive selection genes (atp8, nad3, nad6, ccmFn, and matR) in seagrasses that may be associated with their adaptation to the marine environment. CONCLUSIONS: In this study, we sequenced and annotated the mt genomes of Z. japonica and P. iwatensis and compared them with the genome of other monocotyledons. The results of this study will enhance our understanding of seagrass adaptation to the marine environment and can inform further investigations of the seagrass mt genome.
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Genoma Mitocondrial , Magnoliopsida , Genoma Mitocondrial/genética , Filogenia , Aclimatação/genética , Tamanho do GenomaRESUMO
Impairment of PINK1/parkin-mediated mitophagy is currently proposed to be the molecular basis of mitochondrial abnormality in Parkinson's disease (PD). We here demonstrate that PINK1 directly phosphorylates Drp1 on S616. Drp1S616 phosphorylation is significantly reduced in cells and mouse tissues deficient for PINK1, but unaffected by parkin inactivation. PINK1-mediated mitochondrial fission is Drp1S616 phosphorylation dependent. Overexpression of either wild-type Drp1 or of the phosphomimetic mutant Drp1S616D , but not a dephosphorylation-mimic mutant Drp1S616A , rescues PINK1 deficiency-associated phenotypes in Drosophila. Moreover, Drp1 restores PINK1-dependent mitochondrial fission in ATG5-null cells and ATG7-null Drosophila. Reduced Drp1S616 phosphorylation is detected in fibroblasts derived from 4 PD patients harboring PINK1 mutations and in 4 out of 7 sporadic PD cases. Taken together, we have identified Drp1 as a substrate of PINK1 and a novel mechanism how PINK1 regulates mitochondrial fission independent of parkin and autophagy. Our results further link impaired PINK1-mediated Drp1S616 phosphorylation with the pathogenesis of both familial and sporadic PD.
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Proteínas de Drosophila , Mitofagia , Animais , Proteínas de Drosophila/genética , Humanos , Camundongos , Mitocôndrias/genética , Dinâmica Mitocondrial , Mitofagia/genética , Proteínas Quinases/genética , Ubiquitina-Proteína Ligases/genéticaRESUMO
OBJECTIVE: To provide evidence of the association between CLTA-4 gene polymorphisms and alopecia areata (AA). METHODS: PubMed, EMBASE, Web of Science, Cochrane, Wanfang, and CNKI databases were searched until 30 April 2021. The selection was completed according to the inclusion and exclusion criteria. The study quality assessment was based on Newcastle-Ottawa Scale. The assessment of the association was measured by ORs and 95%CIs. RESULTS: Nine studies, containing 2858 AA cases and 5444 disease-free control subjects were included. For rs231775 polymorphism, no significant association with AA was found, which was A vs. a, OR = 1.02 [0.81, 1.30], p = 0.85; AA vs. aa, OR = 1.26 [0.81, 1.97], p = 0.31; Aa vs. aa, OR = 1.04 [0.54, 2.01], p = 0.91; AA + Aa vs. aa, OR = 1.04 [0.71, 1.53], p = 0.82; AA vs. Aa + aa, OR = 1.31 [0.97, 1.78], p = 0.08. For rs3087243 polymorphism, also no significant association was found, which was A vs. a, OR = 0.93 [0.78, 1.11]; p = 0.40, AA vs. aa, OR = 0.68 [0.44, 1.06]; p = 0.09; Aa vs. aa, OR = 0.87 [0.45, 1.68], p = 0.68; AA + Aa vs. aa, OR = 0.93 [0.68, 1.28], p = 0.66; AA vs. Aa + aa, OR = 0.78 [0.34, 1.81], p = 0.57. For rs231726 polymorphism, a significant correlation was found, which was A vs. a, OR = 0.76 [0.70, 0.82], p < 0.05. CONCLUSIONS: A significant correlation between CTLA-4 rs231726 polymorphism and AA susceptibility was found, but no significant association of CTLA-4 gene rs231775 and rs3087243 polymorphisms and AA susceptibility was found.
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Alopecia em Áreas , Antígeno CTLA-4/metabolismo , Alopecia em Áreas/genética , Antígeno CTLA-4/genética , Predisposição Genética para Doença/genética , Humanos , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Paddy rice is a typical wetland plant species, and mercury (Hg) accumulation in this rice has received much attention over the last two decades. The role of root iron plaque on rice Hg accumulation is not well understood. The effects of iron plaque on Hg0 uptake, translocation, and volatilization in rice seedlings were investigated under hydroponic conditions using different rice genotypes. After induction of iron plaque on rice roots with pretreatment solutions containing 0, 15 and 30 mg Fe2+L-1, rice seedlings were transplanted into specially designed airtight culture chambers, where roots were separated from the aerial parts and exposed to saturated Hg0 vapor. The results showed the following: (1) There were significant differences in the amount of iron plaque formed on the rice roots among the three genotypes. (2) A significant correlation was observed between the concentrations of Hg and Fe in the iron plaque of the root surface for the three genotypes (R2 = 0.933, p < 0.01). (3) Iron plaque may act as a barrier for Hg0 behavior, i.e., inhibiting the process of Hg0 uptake and translocation from the rhizosphere.
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Mercúrio , Oryza , Ferro , Volatilização , Raízes de Plantas , PlântulaRESUMO
BACKGROUND: Cholinergic anti-inflammatory pathway (CAP) is implicated in cardioprotection in chronic heart failure (CHF) by downregulating inflammation response. Mitochondrial injuries play an important role in ventricular remodeling of the CHF process. Herein, we aim to investigate whether CAP elicitation prevents ventricular remodeling in CHF by protecting myocardial mitochondrial injuries and its underlying mechanisms. METHODS AND RESULTS: CHF models were established by ligation of anterior descending artery for 5 weeks. Postoperative survival rats were assigned into 5 groups: the sham group (sham, n = 10), CHF group (CHF, n = 11), Vag group (CHF+vagotomy, n = 10), PNU group (CHF+PNU-282987 for 4 weeks, n = 11), and Vag+PNU group (CHF+vagotomy+PNU-282987 for 4 weeks, n = 10). The antiventricular remodeling effect of cholinergic elicitation was evaluated in vivo, and H9C2 cells were selected for the TNF-α gradient stimulation experiment in vitro. In vivo, CAP agitated by PNU-282987 alleviated the left ventricular dysfunction and inhibited the energy metabolism remodeling. Further, cholinergic elicitation increased myocardium ATP levels and reduced systemic inflammation. CAP induction alleviates macrophage infiltration and cardiac fibrosis, of which the effect is counteracted by vagotomy. Myocardial mitochondrial injuries were ameliorated by CAP activation, including the reserved ultrastructural integrity, declining ROS overload, reduced myocardial apoptosis, and enhanced mitochondrial fusion. In vitro, TNF-α intervention significantly exacerbated the mitochondrial damage in H9C2 cells. CONCLUSION: CAP elicitation effectively improves ischemic ventricular remodeling by suppressing systemic and cardiac inflammatory response, attenuating cardiac fibrosis and potentially alleviating the mitochondrial dysfunction linked to hyperinflammation reaction.
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Insuficiência Cardíaca/etiologia , Inflamação/prevenção & controle , Mitocôndrias Cardíacas/patologia , Isquemia Miocárdica/complicações , Remodelação Ventricular , Receptor Nicotínico de Acetilcolina alfa7/fisiologia , Animais , Benzamidas/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Doença Crônica , Citocinas/biossíntese , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
The effects of ultraviolet (UV) radiation, particularly UV-B on algae, have become an important issue as human-caused depletion of the protecting ozone layer has been reported. In this study, the effects of different short-term UV-B radiation on the growth, physiology, and metabolism of Porphyra haitanensis were examined. The growth of P. haitanensis decreased, and the bleaching phenomenon occurred in the thalli. The contents of total amino acids, soluble sugar, total protein, and mycosporine-like amino acids (MAAs) increased under different UV-B radiation intensities. The metabolic profiles of P. haitanensis differed between the control and UV-B radiation-treated groups. Most of the differential metabolites in P. haitanensis were significantly upregulated under UV-B exposure. Short-term enhanced UV-B irradiation significantly affected amino acid metabolism, carbohydrate metabolism, glutathione metabolism, and phenylpropane biosynthesis. The contents of phenylalanine, tyrosine, threonine, and serine were increased, suggesting that amino acid metabolism can promote the synthesis of UV-absorbing substances (such as phenols and MAAs) by providing precursor substances. The contents of sucrose, D-glucose-6-phosphate, and beta-D-fructose-6-phosphate were increased, suggesting that carbohydrate metabolism contributes to maintain energy supply for metabolic activity in response to UV-B exposure. Meanwhile, dehydroascorbic acid (DHA) was also significantly upregulated, denoting effective activation of the antioxidant system. To some extent, these results provide metabolic insights into the adaptive response mechanism of P. haitanensis to short-term enhanced UV-B radiation.
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Porphyra/metabolismo , Porphyra/efeitos da radiação , Aminoácidos/metabolismo , Redes e Vias Metabólicas/fisiologia , Redes e Vias Metabólicas/efeitos da radiação , Proteínas de Plantas/metabolismo , Porphyra/fisiologia , Açúcares/metabolismo , Raios UltravioletaRESUMO
The perception of bitter taste is linked to the detection of toxins. Therefore, it facilitates avoiding the consumption of potential toxins in the diet. At the molecular level, bitter taste is mediated by taste 2 receptors (Tas2rs). Studies on Tas2r have made major advances in recent years. However, little is known about Tas2rs in Squamata, the second largest order of extant vertebrates. To explore the repertoire and phylogenetic relationships among Tas2r genes in Squamata, we identified and characterized Tas2rs from genome assemblies of 15 Squamata species. We observed considerable Tas2r contraction and expansion in the suborders Serpentes and Lacertilia, respectively. Phylogenetic and reconciliation analysis suggested that lineage-specific gene gains and losses could have led to the Tas2r contraction and expansion in Squamata. Different Tas2r repertoires in Serpents and Lacertilia also reflect their oral anatomical features and taste behaviors. Our findings offer novel perspectives into the study of taste and dietary protection in Squamata species.
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Filogenia , Receptores Acoplados a Proteínas G/genética , Répteis/genética , Paladar , Animais , Evolução Molecular , Família Multigênica , Répteis/classificaçãoRESUMO
Carnivores exhibit various fat contents and energy reserves to adapt to their environments. However, the molecular mechanisms underlying lipid metabolic differences among carnivores have not been well explored. Long-chain acyl-CoA synthetases (ACSLs) catalyze the initial step in lipid metabolism by activating fatty acids (FAs), and they drive acyl-CoAs toward anabolic lipid synthesis or catabolic ß-oxidation. We identified the sequences of the genes of the ACSL family (ACSL1, ACSL3, ACSL4, ACSL5 and ACSL6) in the sable (Martes zibellina) via transcriptome sequencing. The ACSL gene sequences of 13 other carnivores were obtained from NCBI. Phylogenetic results showed that unlike the widely accepted carnivore phylogeny, Canidae and Felidae tend to group together based on ACSL4 and ACSL6. The evolutionary analyses identified a series of positively selected amino acid residues in ACSL1, ACSL4 and ACSL5. Two radical amino acid substitutions detected in sable suggested potential insights into the molecular mechanism underlying the relatively low fat content in this animal. This is the first study to investigate the molecular mechanisms underlying the adaptive evolution of fat metabolism in carnivores. Overall, the ACSL genes were under different evolutionary forces in carnivores, and some genes have undergone adaptive evolution in lipid metabolism.
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Carnivoridade , Coenzima A Ligases/genética , Evolução Molecular , Mustelidae/genética , Animais , Coenzima A Ligases/química , Coenzima A Ligases/metabolismo , Metabolismo dos Lipídeos , Família Multigênica , Mustelidae/metabolismo , Mustelidae/fisiologia , Filogenia , TranscriptomaRESUMO
OBJECTIVE: This study aimed to evaluate the hepatotoxicity, metabolic disturbance activity and endocrine disrupting activity of mice treated by Decabromodiphenyl ethane (DBDPE). METHODS: In this study, Balb/C mice were treated orally by gavage with various doses of DBDPE. After 30 days of treatment, mice were sacrificed; blood, livers and thyroid glands were obtained, and hepatic microsomes were isolated. Biochemical parameters including 8 clinical chemistry parameters, blood glucose and hormone levels including insulin and thyroid hormone were assayed. The effects of DBDPE on hepatic cytochrome P450 (CYP) levels and activities and uridinediphosphate-glucuronosyltransferase (UDPGT) activities were investigated. Liver and thyroid glands were observed. RESULTS: There were no obvious signs of toxicity and no significant treatment effect on body weight, or liver-to-body weight ratios between treatment groups. The levels of ALT and AST of higher dose treatment groups were markedly increased. Blood glucose levels of treatment groups were higher than those of control group. There was also an induction in TSH, T3, and fT3. UDPGT, PROD, and EROD activities were found to have been increased significantly in the high dose group. Histopathologic liver changes were characterized by hepatocyte hypertrophy and cytoplasmic vacuolization. Our findings suggest that DBDPE can cause a certain degree of mouse liver damage and insufficiency. CONCLUSION: DBDPE has the activity of endocrine disruptors in Bal/C mice, which may induce drug-metabolizing enzymes including CYPs and UDPGT, and interfere with thyroid hormone levels mediated by AhR and CAR signaling pathways. Endocrine disrupting activity of DBDPE could also affect the glucose metabolism homeostasis.
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Bromobenzenos/toxicidade , Dieta , Disruptores Endócrinos/toxicidade , Administração Oral , Ração Animal , Animais , Glicemia , Peso Corporal/efeitos dos fármacos , Bromobenzenos/administração & dosagem , Relação Dose-Resposta a Droga , Disruptores Endócrinos/administração & dosagem , Poluentes Ambientais/administração & dosagem , Poluentes Ambientais/toxicidade , Feminino , Retardadores de Chama , Regulação da Expressão Gênica/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Tamanho do Órgão/efeitos dos fármacosRESUMO
BACKGROUND: The wolf (Canis lupus) is one of the most widely distributed terrestrial mammals, because it is well adapted to various ecological niches and their corresponding pathogen environments. Immunological competence is a crucial factor involved in adapting to a changing environment and fighting pathogen infection in animals. In this study, the peripheral blood transcriptome of wolves was generated via RNA-seq to advance understanding of the wolf immunome, with a special focus on the major histocompatibility complex class I (MHC I) and toll-like receptor (TLR) gene families, which are involved in pathogen recognition and defense. RESULTS: The blood transcriptomic libraries of eight wolves originating from Tibet and Inner Mongolia were sequenced, and approximately 383 million reads were generated. Using a genome-guided assembly strategy, we obtained 123,851 unigenes, with a mean length of 845 bp and an N50 length of 1121 bp. On the basis of BLAST searches against the NCBI non-redundant protein database (Nr), a total of 36,192 (29.22%) unigenes were annotated. For functional classification, 24,663 unigenes were assigned to 13,016 Gene Ontology (GO) terms belonging to 51 sub-categories of the three main GO categories. Additionally, 7682 unigenes were classified into 6 Kyoto Encyclopedia of Genes and Genomes (KEGG) categories, in which the most represented functional sub-categories were signal transduction and the immune system, and 16,238 unigenes were functionally classified into 25 Eukaryotic Orthologous Groups (KOG) categories. We observed an overall higher ω (d N/d S) value at antigen-binding sites (ABSs) than at non-ABS regions as well as clear evidence of intergenic/intragenic recombination events at wolf MHC I loci. Additionally, our analysis revealed that carnivorous TLRs were dominated by purifying selection, with mean ω values at each TLR locus ranging from 0.173 to 0.527. However, we also found significant instances of positive selection that acted on several codons in pathogen recognition domains and were linked to species-specific differences in pathogen recognition. CONCLUSIONS: This study represents the first attempt to characterize the blood transcriptome of the wolf and to highlight the value of investigating the immune system. Balancing selection and recombination have contributed to the historical evolution of wolf MHC I genes. Moreover, TLRs in carnivores have undergone adaptive evolution against the background of purifying selection, and a high level of adaptive evolution was detected in the wolf TLR system.
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Adaptação Fisiológica/genética , Evolução Molecular , Perfilação da Expressão Gênica , Genes MHC Classe I/genética , Leucócitos Mononucleares/metabolismo , Receptores Toll-Like/genética , Lobos/genética , Animais , Anotação de Sequência Molecular , Seleção Genética , Lobos/sangue , Lobos/fisiologiaRESUMO
Bitter taste receptors (Tas2rs) play important roles in mammalian defense mechanisms by helping animals detect and avoid toxins in food. Although Tas2r genes have been widely studied in several mammals, minimal research has been performed in canids. To analyze the genetic basis of Tas2r genes in canids, we first identified Tas2r genes in the wolf, maned wolf, red fox, corsac fox, Tibetan fox, fennec fox, dhole and African hunting dog. A total of 183 Tas2r genes, consisting of 118 intact genes, 6 partial genes and 59 pseudogenes, were detected. Differences in the pseudogenes were observed among nine canid species. For example, Tas2r4 was a pseudogene in the dog but might play a functional role in other canid species. The Tas2r42 and Tas2r10 genes were pseudogenes in the maned wolf and dhole, respectively, and the Tas2r5 and Tas2r34 genes were pseudogenes in the African hunting dog; however, these genes were intact genes in other canid species. The differences in Tas2r pseudogenes among canids might suggest that the loss of intact Tas2r genes in canid species is species-dependent. We further compared the 183 Tas2r genes identified in this study with Tas2r genes from ten additional carnivorous species to evaluate the potential influence of diet on the evolution of the Tas2r gene repertoire. Phylogenetic analysis revealed that most of the Tas2r genes from the 18 species intermingled across the tree, suggesting that Tas2r genes are conserved among carnivores. Within canids, we found that some Tas2r genes corresponded to the traditional taxonomic groupings, while some did not. PIC analysis showed that the number of Tas2r genes in carnivores exhibited no positive correlation with diet composition, which might be due to the limited number of carnivores included in our study.