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A critical shortage of donor corneas exists worldwide. Hydrogel patches with a biological architecture and functions that simulate those of native corneas have garnered considerable attention. This study introduces a stromal structure replicating corneal patch (SRCP) composed of a decellularized cornea-templated nanotubular skeleton, recombinant human collagen, and methacrylated gelatin, exhibiting a similar ultrastructure and transmittance (above 80 %) to natural cornea. The SRCP is superior to the conventional recombinant human collagen patch in terms of biomechanical properties and resistance to enzymatic degradation. Additionally, SRCP promotes corneal epithelial and stromal cell migration while preventing the trans-differentiation of stromal cells into myofibroblasts. When applied to an ocular surface (37 °C), SRCP releases methacrylated gelatin, which robustly binds SRCP to the corneal stroma after activation by 405 nm light. Compared to gelatin-based photocurable hydrogel, the SRCP better supports the restoration of normal corneal curvature and withstands deformation under an elevated intraocular pressure (100 mmHg). In an in vivo deep anterior-corneal defect model, SRCP facilitated epithelial healing and vision recovery within 2 weeks, maintained graft structural stability, and inhibited stromal scarring at 4 weeks post-operation. The ideal performance of the SRCP makes it a promising humanized corneal equivalent for sutureless clinical applications.
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Substância Própria , Hidrogéis , Humanos , Animais , Hidrogéis/química , Gelatina/química , Cicatrização/efeitos dos fármacos , Colágeno/química , Coelhos , Procedimentos Cirúrgicos sem Sutura/métodos , CórneaRESUMO
Diabetic mellitus (DM) causes various complications, including the corneal endothelial dysfunction that leads to corneal edema and vision loss, especially in the DM patients with intraocular surgeries. However, the pathogenic mechanism of hyperglycemia-caused corneal endothelial dysfunction remains incomplete understood. Here we firstly screened and identified the glutamine contents of aqueous humor (AH) were significantly reduced in the type 2 diabetic patients and type 1 and type 2 diabetic mice. To explore the potential therapeutic effects of glutamine (Gln) supplement on the protection of diabetic corneal endothelial dysfunction, we performed the anterior chamber perfusion with the addition of L-alanyl-L-glutamine (Ala-Gln), and confirmed that Ala-Gln supplement not only accelerated the resolution of corneal edema and recovery of corneal thickness, but also preserved the regular arrangement and barrier-pump function of cornea. Mechanistically, we revealed that the supplements of Ala-Gln protect corneal endothelial cells (CECs) from the deleterious effects of high glucose-induced oxidative stress, mitochondrial dysfunction, and cell apoptosis. Overall, these results indicate the Gln depletion plays an important role in the diabetic corneal endothelial dysfunction, while the Ala-Gln supplement during intraocular surgery provide an effective prevention strategy through regulating the redox homeostasis and mitochondrial function of corneal endothelium.
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Jinhua finger citron is one of the traditional specialties of Jinhua with a long history of cultivation. The current study highlighted the advantages of using the quality by design approach to optimize the ultrasonic-assisted distillation extraction of Jinhua finger citron essential oil. The yield of Jinhua finger citron essential oil was regarded as a potential critical quality attribute. Potential critical process parameters were screened by the definitive screening design. Finally, the design space of the essential oil extraction process was constructed. The optimal operating space included an auxiliary NaCl concentration range of 9-12.00%, a soak temperature range of 30-50 °C, a distillation time range of 3.5-4.00 h, an ultrasonic power range of 200-300 W, a solid-liquid ratio range of 1:3-1:3.5, and a soak time range of 40-80 min. On this basis, the relative density, refractive index, and pH values of different batches of Jinhua finger citron essential oil were checked. The involved batches were analyzed by gas chromatography (GC), and gas chromatographic fingerprints were established by identifying major compounds, including d-limonene, γ-terpinene, and 5,7-dimethoxycoumarin. Based on the "quality by design" strategy, the extraction process of Jinhua finger citron essential oil established in this study was robust, reliable, and flexible.
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Infectious bursal disease (IBD) is an acute and fatal immunosuppressive disease caused by infectious bursal disease virus (IBDV). As an obligate intracellular parasite, IBDV infection is strictly regulated by host factors. Knowledge on the antiviral activity and possible mechanism of host factors might provide the theoretical basis for the prevention and control of IBD. In this study, RNA-sequencing results indicated that many host factors were induced by IBDV infection, among which the expression levels of OASL (2´,5´-oligadenylate synthetase-like protein) was significantly upregulated. OASL overexpression significantly inhibited IBDV replication, whereas OASL knockdown promoted IBDV replication. Interestingly, the antiviral ability of OASL was independent of its canonical enzymatic activity, i.e., OASL targeted viral protein VP2 for degradation, depending on the autophagy receptor p62/SQSTM1 in the autophagy pathway. Additionally, the 316 lysine (K) of VP2 was the key site for autophagy degradation, and its replacement with arginine disrupted VP2 degradation induced by OASL and enhanced IBDV replication. Importantly, our results for the first time indicate a unique and potent defense mechanism of OASL against double-stranded RNA virus by interaction with viral proteins, which leads to their degradation. IMPORTANCE: OASL (2´,5´-oligadenylate synthetase-like protein) exhibits broad-spectrum antiviral effects against single-stranded RNA viruses in mammals, potentially serving as a promising target for novel antiviral strategies. However, its role in inhibiting the replication of double-stranded RNA viruses (dsRNA viruses), such as infectious bursal disease virus (IBDV), in avian species remains unclear. Our findings indicated a unique and potent defense mechanism of OASL against dsRNA viruses. It has been previously shown in mammals that OASL inhibits virus replication through increasing interferon production. The groundbreaking aspect of our study is the finding that OASL has the ability to interact with IBDV viral protein VP2 and target it for degradation and thus exerts its antiviral effect. Our results reveal the interaction between avian natural antiviral immune response and IBDV infection. Our study not only enhances our understanding of bird defenses against viral infections but can also inform strategies for poultry disease management.
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2',5'-Oligoadenilato Sintetase , Autofagia , Infecções por Birnaviridae , Galinhas , Vírus da Doença Infecciosa da Bursa , Proteínas Estruturais Virais , Replicação Viral , Vírus da Doença Infecciosa da Bursa/fisiologia , Animais , Infecções por Birnaviridae/virologia , Infecções por Birnaviridae/metabolismo , Proteínas Estruturais Virais/metabolismo , Proteínas Estruturais Virais/genética , 2',5'-Oligoadenilato Sintetase/metabolismo , 2',5'-Oligoadenilato Sintetase/genética , Doenças das Aves Domésticas/virologia , Doenças das Aves Domésticas/metabolismo , Interações Hospedeiro-Patógeno , Células HEK293 , Humanos , Linhagem CelularRESUMO
The subgroup J avian leukosis virus (ALV-J), a retrovirus, uses its gp85 protein to bind to the receptor, the chicken sodium hydrogen exchanger isoform 1 (chNHE1), facilitating viral invasion. ALV-J is the main epidemic subgroup and shows noteworthy mutations within the receptor-binding domain (RBD) region of gp85, especially in ALV-J layer strains in China. However, the implications of these mutations on viral replication and transmission remain elusive. In this study, the ALV-J layer strain JL08CH3-1 exhibited a more robust replication ability than the prototype strain HPRS103, which is related to variations in the gp85 protein. Notably, the gp85 of JL08CH3-1 demonstrated a heightened binding capacity to chNHE1 compared to HPRS103-gp85 binding. Furthermore, we showed that the specific N123I mutation within gp85 contributed to the enhanced binding capacity of the gp85 protein to chNHE1. Structural analysis indicated that the N123I mutation primarily enhanced the stability of gp85, expanded the interaction interface, and increased the number of hydrogen bonds at the interaction interface to increase the binding capacity between gp85 and chNHE1. We found that the N123I mutation not only improved the viral replication ability of ALV-J but also promoted viral shedding in vivo. These comprehensive data underscore the notion that the N123I mutation increases receptor binding and intensifies viral replication.
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Vírus da Leucose Aviária , Leucose Aviária , Doenças das Aves Domésticas , Animais , Vírus da Leucose Aviária/genética , Vírus da Leucose Aviária/química , Mutação , Galinhas , Isoformas de Proteínas/genética , Proteínas do Envelope Viral/genéticaRESUMO
A 65-year-old man presented with asymptomatic retroperitoneal mass that had been detected on ultrasonography performed during a physical screening. He had no hematochezia, hematuria or any other symptoms. Tumor markers were normal, including alpha fetoprotein, carcinoembryonic antigen, neuron-specific enolase and cancer antigen 199. Abdominal CT demonstrated a retroperitoneal mass (white arrow) accompanied by significant thickening of the jejunal wall, involving the left kidney. After enhancement, the mass showed rapid enhancement at arterial phase and venous phase, showed washout at delayed phase. Multi-planar reformation revealed the mass involving the pancreatic tail and the left renal pelvis. Surgical resection was performed and pathological examination confirmed clear cell renal cell carcinoma involving pancreas and jejunum, with immunohistochemical results as follows: CK (partly +), Vimentin (partly +), Pax-8 (+), CD10 (+), P505s (partly +), CA-IX (+), TFE-3 (-), Syn (-), CgA (-), CD56 (+), S-100 (-), SOX-10 (-), HMB-45 (-), Desmin (-),CD117 (-), DOG-1 (-), Melan-A (-), SMA (-), CD34 (+), CD31 (+), CD68 (+), Ki67 (5%+). Discussion.
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Subgroup K avian leukosis virus (ALV-K) is a novel subgroup of ALV isolated from Chinese native chickens. As for a retrovirus, the interaction between its envelope protein and cellular receptor is a crucial step in ALV-K infection. Tva, a protein previously determined to be associated with vitamin B12/cobalamin uptake, has been identified as the receptor of ALV-K. However, the molecular mechanism underlying the interaction between Tva and the envelope protein of ALV-K remains unclear. In this study, we identified the C-terminal loop of the LDL-A module of Tva as the minimal functional domain that directly interacts with gp85, the surface component of the ALV-K envelope protein. Further point-mutation analysis revealed that E53, L55, H59, and G70, which are exposed on the surface of Tva and are spatially adjacent, are key residues for the binding of Tva and gp85 and facilitate the entry of ALV-K. Homology modeling analysis indicated that the substitution of these four residues did not significantly impact the Tva structure but impaired the interaction between Tva and gp85 of ALV-K. Importantly, the gene-edited DF-1 cell line with precisely substituted E53, L55, H59, and G70 was completely resistant to ALV-K infection and did not affect vitamin B12/cobalamin uptake. Collectively, these findings not only contribute to a better understanding of the mechanism of ALV-K entry into host cells but also provide an ideal gene-editing target for antiviral study.
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Vírus da Leucose Aviária , Doenças das Aves Domésticas , Receptores Virais , Vitamina B 12 , Animais , Vírus da Leucose Aviária/genética , Galinhas/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores Virais/metabolismo , Proteínas do Envelope Viral/metabolismo , Complexo Vitamínico B , Vitamina B 12/metabolismoRESUMO
The receptor of the subgroup A avian leukosis virus (ALV-A) in chicken is Tva, which is the homologous protein of human CD320 (huCD320), contains a low-density lipoprotein (LDL-A) module and is involved in the uptake of transcobalamin bound vitamin B12/cobalamin (Cbl). To map the functional determinants of Tva responsible for ALV-A receptor activity, a series of chimeric receptors were created by swapping the LDL-A module fragments between huCD320 and Tva. These chimeric receptors were then used for virus entry and binding assays to map the minimal ALV-A functional domain of Tva. The results showed that Tva residues 49 to 71 constituted the minimal functional domain that directly interacted with the ALV-A gp85 protein to mediate ALV-A entry. Single-residue substitution analysis revealed that L55 and W69, which were spatially adjacent on the surface of the Tva structure, were key residues that mediate ALV-A entry. Structural alignment results indicated that L55 and W69 substitutions did not affect the Tva protein structure but abolished the interaction force between Tva and gp85. Furthermore, substituting the corresponding residues of huCD320 with L55 and W69 of Tva converted huCD320 into a functional receptor of ALV-A. Importantly, soluble huCD320 harboring Tva L55 and W69 blocked ALV-A entry. Finally, we constructed a Tva gene-edited cell line with L55R and W69L substitutions that could fully resist ALV-A entry, while Cbl uptake was not affected. Collectively, our findings suggested that amino acids L55 and W69 of Tva were key for mediating virus entry. IMPORTANCE Retroviruses bind to cellular receptors through their envelope proteins, which is a crucial step in infection. While most retroviruses require two receptors for entry, ALV-A requires only one. Various Tva alleles conferring resistance to ALV-A, including Tvar1 (C40W substitution), Tvar2 (frame-shifting four-nucleotide insertion), Tvar3, Tvar4, Tvar5, and Tvar6 (deletion in the first intron), are known. However, the detailed entry mechanism of ALV-A in chickens remains to be explored. We demonstrated that Tva residues L55 and W69 were key for ALV-A entry and were important for correct interaction with ALV-A gp85. Soluble Tva and huCD320 harboring the Tva residues L55 and W69 effectively blocked ALV-A infection. Additionally, we constructed gene-edited cell lines targeting these two amino acids, which completely restricted ALV-A entry without affecting Cbl uptake. These findings contribute to a better understanding of the infection mechanism of ALV-A and provided novel insights into the prevention and control of ALV-A.
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Aminoácidos , Vírus da Leucose Aviária , Aminoácidos/metabolismo , Animais , Leucose Aviária/virologia , Vírus da Leucose Aviária/metabolismo , Proteínas Aviárias/genética , Proteínas Aviárias/metabolismo , Galinhas/metabolismo , Humanos , Lipoproteínas LDL/metabolismo , Nucleotídeos/metabolismo , Receptores Virais/genética , Receptores Virais/metabolismo , Transcobalaminas/metabolismo , Vitamina B 12/metabolismoRESUMO
Isoflavones possess a wide range of physiological effects. However, it is still unclear whether isoflavones can promote milk synthesis in mammary gland. This study aimed to determine the effects of a main soy isoflavone, daidzein, on milk synthesis and proliferation of mammary epithelial cells (MECs) and reveal the underlying molecular mechanism. Primary bovine MECs were treated with different concentrations of daidzein (0, 5, 10, 20, 40, and 80 µM). Daidzein dose-dependently promoted α- and ß-casein and lipid synthesis, cell cycle transition, and cell amount, with the best stimulatory effect at 20 µM. Daidzein also stimulated mTOR activation and Cyclin D1 and SREBP-1c expression. Daidzein induced the expression and nuclear localization of estrogen receptor α (ERα), and ERα knockdown blocked the stimulation of daidzein on these above signaling pathways. ERα knockdown also abolished the stimulation of daidzein on NFκB1 expression and phosphorylation, and NFκB1 was required for daidzein to enhance the mTOR, Cyclin D1 and SREBP-1c signaling pathways. In summary, our findings reveal that daidzein stimulates milk synthesis and proliferation of MECs via the ERα-dependent NFκB1 activation.
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Isoflavonas , Leite , Animais , Bovinos , Proliferação de Células , Células Epiteliais , Receptor alfa de Estrogênio/genética , Isoflavonas/farmacologia , Glândulas Mamárias AnimaisRESUMO
Infectious bursal disease virus (IBDV), a double-stranded RNA virus, causes immunosuppression and high mortality in 3-6-week-old chickens. Innate immune defense is a physical barrier to restrict viral replication. After viral infection, the host shows crucial defense responses, such as stimulation of antiviral effectors to restrict viral replication. Here, we conducted RNA-seq in avian cells infected by IBDV and identified TRIM25 as a host restriction factor. Specifically, TRIM25 deficiency dramatically increased viral yields, whereas overexpression of TRIM25 significantly inhibited IBDV replication. Immunoprecipitation assays indicated that TRIM25 only interacted with VP3 among all viral proteins, mediating its K27-linked polyubiquitination and subsequent proteasomal degradation. Moreover, the Lys854 residue of VP3 was identified as the key target site for the ubiquitination catalyzed by TRIM25. The ubiquitination site destroyed enhanced the replication ability of IBDV in vitro and in vivo. These findings demonstrated that TRIM25 inhibited IBDV replication by specifically ubiquitinating and degrading the structural protein VP3.
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Infecções por Birnaviridae/imunologia , Vírus da Doença Infecciosa da Bursa/imunologia , Proteínas com Motivo Tripartido/imunologia , Proteínas Estruturais Virais/metabolismo , Replicação Viral/imunologia , Animais , Galinhas , Proteínas com Motivo Tripartido/metabolismo , UbiquitinaçãoRESUMO
Avian leukosis virus (ALV) can induce various tumors and cause serious production problems. ALVs isolated from chickens were divided into six subgroups (A-J). In 2012, a strain of a putative novel subgroup of ALVs was isolated from Chinese native chickens in Jiangsu Province and named as ALV-K. In this study, three ALV-K strains (JS14LH01, JS13LH14, and JS15SG01) were isolated from chickens with suspected ALV infection in Jiangsu Province. Their complete genomes were amplified, sequenced, and analyzed systematically. The results showed that JS14LH01 and JS13LH14 were ALV-K and ALV-E recombinant strains. Whereas JS15SG01 is an ALV-K, ALV-E, and ALV-J multiple recombinant strain containing the U3 region of ALV-J. The pathogenicity test of JS15SG01 revealed that, compared with previous ALV-K strains, the viremia and viral shedding level of JS15SG01-infected chickens were significantly increased, reaching 100 % and 59 %, respectively. More important, JS15SG01 induced significant proliferation of gliocytes in the cerebral cortex of infected chickens, accompanied by the neurotropic phenomenon. This is the first report about a multiple recombinant ALV-K strain that could invade and injure the brain tissue of chickens in China. Our findings enriched the epidemiologic data of ALV and helped to reveal the evolution of ALV strains prevalent in chicken fields.
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Vírus da Leucose Aviária/genética , Leucose Aviária/virologia , Galinhas/virologia , Recombinação Genética , Animais , Leucose Aviária/epidemiologia , Vírus da Leucose Aviária/isolamento & purificação , Vírus da Leucose Aviária/patogenicidade , ChinaRESUMO
BACKGROUND: The neutrophil to lymphocyte ratio (NLR) has emerged as a strong predictor of mortality in stroke patients. Our study aimed to investigate the correlation between NLR and cerebral infarction with nonfocal symptoms confirmed by diffusion-weighted imaging (DWI) (+). METHODS: A total of 439 patients with nonfocal stroke symptoms with CT-negative findings were included from January 1 to December 31, 2018. All patients underwent a head MRI examination within seven days following a head CT examination. The patients' demographics, medical history, presenting symptoms, and stroke location were recorded. Logistic regression and receiver operating characteristic (ROC) curve analysis were used to identify variables with a significant association with cerebral infarction. RESULTS: Cerebral infarction was detected in 79 (18%) patients confirmed by DWI(+), located mostly in the cerebellum (40.51%). Dizziness (85.19%) was the most common symptom. The cerebral infarction group showed a higher prevalence of hypertension (P<0.0001), diabetes mellitus (P<0.0001), and smoking status (P=0.001) than non-cerebral infarction group. The NLR (P<0.0001) was higher in the cerebral infarction group. There was no significant difference in NIHSS (P=0.09). Logistic analysis revealed that male gender (P=0.046), a history of hypertension (P=0.001), diabetes mellitus (P=0.001), smoking (P=0.023), and NLR (P<0.0001) were the best predictors of cerebral infarction. When integrating sex, hypertension, diabetes mellitus, smoking and NLR, the area under ROC value of the combined method was 0.785, higher than any separate parameters (P<0.05). CONCLUSIONS: NLR combined with male gender, a history of hypertension, diabetes mellitus, and smoking, could predict DWI-confirmed cerebral infarction with nonfocal neurologic symptoms with high diagnostic accuracy.
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Avian leukosis virus subgroup J (ALV-J) was first isolated from broiler chickens in China in 1999; subsequently, it was rapidly introduced into layer chickens and Chinese local chickens. Recently, the incidence of ALV-J in broiler and layer chickens has significantly decreased. However, it has caused substantial damage to Chinese local chickens, resulting in immense challenges to their production performance and breeding safety. To systematically analyze the molecular characteristics and the epidemic trend of ALV-J in Chinese local chickens, 260 clinical samples were collected for the period of 2013-2018; 18 ALV-J local chicken isolates were identified by antigen-capture enzyme-linked immunosorbent assay and subgroup A-, B-, and J-specific multiplex PCR. The whole genomic sequences of 18 isolates were amplified with PCR and submitted to GenBank. Approximately, 55.5% (10/18) of the 18 isolates demonstrated a relatively high homology (92.3-95.4%) with 20 ALV-J early-isolated local strains (genome sequences obtained from GenBank) in gp85 genes clustering in a separated branch. The 3' untranslated region (3' UTR) of the 18 isolates showed a 195-210 and 16-28 base pair deletion in the redundant transmembrane region and in direct repeat 1, respectively; 55.5% (10/18) of the 18 isolates retained the 147 residue E element. The U3 gene of 61.1% (11/18) of the 18 isolates shared high identity (94.6-97.3%) with ALV-J early-isolated local strains. These results implied that the gp85 and U3 of ALV-J local chicken isolates have rapidly evolved and formed a unique local chicken branch. In addition, it was determined that the gene deletion in the 3'UTR region currently serves as a unique molecular characteristic of ALV-J in China. Hence, the obtained results built on the existing ALV-J molecular epidemiological data and further elucidated the genetic evolution trend of ALV-J in Chinese local chickens.
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Vírus da Leucose Aviária , Leucose Aviária , Doenças das Aves Domésticas , Animais , Leucose Aviária/epidemiologia , Vírus da Leucose Aviária/genética , Galinhas , China/epidemiologia , Filogenia , Reação em Cadeia da Polimerase , Doenças das Aves Domésticas/epidemiologiaRESUMO
Gossypol, a toxic polyphenol extracted from cotton seeds, is hazardous to human and animal health. Taurine is considered as an essential or semi-essential amino acid and has diverse cytoprotective effects. This study was aimed to investigate the protective effect and molecular mechanism of taurine against apoptosis of C2C12 mouse myoblasts induced by gossypol. C2C12 mouse myoblasts were exposed to gossypol (0, 1 nM, 10 nM, 100 nM, 1 µM, and 10 µM). Cell numbers were rapidly decreased with increasing concentrations of gossypol. Gossypol significantly induced apoptosis, decreased Bcl2 expression, and increased the protein levels of Bax and the cleaved caspase 3. Taurine (0.24 mM) treatment largely rescued the cell number decreased by gossypol, attenuated gossypol-induced cell apoptosis. GPR87 knockdown abolished the inhibition by taurine of cell apoptosis. Furthermore, GPR87 overexpression attenuated cell apoptosis induced by gossypol. Both taurine treatment and GPR87 overexpression stimulated AKT phosphorylation but inhibited AMPK phosphorylation, whereas gossypol had the opposite effects. Taurine treatment promoted GPR87 expression and subcellular localization and partially rescued the inhibition of gossypol on this expression. In summary, these data reveal that taurine attenuates gossypol-induced apoptosis of C2C12 mouse myoblasts via the GPR87-AMPK/AKT signaling.
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Proteínas Quinases Ativadas por AMP/metabolismo , Apoptose , Gossipol/toxicidade , Mioblastos/citologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Ácidos Lisofosfatídicos/metabolismo , Taurina/farmacologia , Proteínas Quinases Ativadas por AMP/genética , Animais , Células Cultivadas , Anticoncepcionais Masculinos/toxicidade , Camundongos , Mioblastos/efeitos dos fármacos , Mioblastos/patologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , Receptores de Ácidos Lisofosfatídicos/genética , Transdução de SinaisRESUMO
Subgroup J avian leukemia virus (ALV-J), belonging to the genus Alpharetrovirus, enters cells through its envelope surface unit (gp85) via specifically recognizing the cellular receptor chicken Na+/H+ exchanger type I (chNHE1), the 28 to 39 N-terminal residues of which were characterized as the minimal receptor functional domain in our previous studies. In this study, to further clarify the precise organization and properties of the interaction between ALV-J gp85 and chNHE1, we identified the chNHE1-binding domain of ALV-J gp85 using a series of gp85 mutants with segment substitutions and evaluating their effects on chNHE1 binding in protein-cell binding assays. Our results showed that hemagglutinin (HA) substitutions of amino acids (aa) 38 to 131 (N terminus of gp85) and aa 159 to 283 (C terminus of gp85) significantly inhibited the interaction between gp85 and chNHE1/chNHE1 loop 1. In addition, these HA-substituted chimeric gp85 proteins could not effectively block the entry of ALV-J into chNHE1-expressing cells. Furthermore, analysis of various N-linked glycosylation sites and cysteine mutants in gp85 revealed that glycosylation sites (N6 and N11) and cysteines (C3 and C9) were directly involved in receptor-gp85 binding and important for the entry of ALV-J into cells. Taken together, our findings indicated that the bipartite sequence motif, spanning aa 38 to 131 and aa 159 to 283, of ALV-J gp85 was essential for binding to chNHE1, with its two N-linked glycosylation sites and two cysteines being important for its receptor-binding function and subsequent viral infection steps.IMPORTANCE Infection of a cell by retroviruses requires the attachment and fusion of the host and viral membranes. The specific adsorption of envelope (Env) surface proteins to cell receptors is a key step in triggering infections and has been the target of antiviral drug screening. ALV-J is an economically important avian pathogen that belongs to the genus Alpharetrovirus and has a wider host range than other ALV subgroups. Our results showed that the amino acids 38 to 131 of the N terminus and 159 to 283 of the C terminus of ALV-J gp85 controlled the efficiency of gp85 binding to chNHE1 and were critical for viral infection. In addition, the glycosylation sites (N6 and N11) and cysteines (C3 and C9) of gp85 played a crucial role in the receptor binding and viral entry. These findings might help elucidate the mechanism of the entry of ALV-J into host cells and provide antiviral targets for the control of ALV-J.
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Vírus da Leucose Aviária/fisiologia , Leucose Aviária/virologia , Receptores Virais/metabolismo , Proteínas do Envelope Viral/metabolismo , Internalização do Vírus , Animais , Vírus da Leucose Aviária/genética , Linhagem Celular , Galinhas/metabolismo , Especificidade de Hospedeiro , Proteínas de Membrana/metabolismo , Doenças das Aves Domésticas/virologia , Domínios Proteicos , Trocadores de Sódio-Hidrogênio/metabolismo , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genéticaRESUMO
Since subgroup J avian leukosis virus (ALV-J) was first isolated in the United Kingdom in 1988, it has seriously hindered the development of the poultry industry worldwide. Although cases of ALV-J infection have been reported as early as 2001 in Pakistan, there was no further research on the isolation and molecular characteristics of ALVs. In the present study, we first isolated two ALVs from suspicious clinical samples that were collected from a desi chicken farm in Pakistan. The results of multiplex PCR and indirect immunofluorescent antibody assays confirmed that the two isolates (PK19FA01 and PK19SA01) belonged to ALV-J. The complete genomes of the two isolates were amplified, sequenced, and systematically analyzed. We found that gp85 of PK19FA01 was more similar to that of the prototype strain HPRS103, whereas gp85 of PK19SA01 was more similar to that of American strains. The two isolates contained an intact E element of 147 residues and had a unique 135 bp deletion in the redundant transmembrane of the 3' untranslated region. The U3 region of the two isolates was highly homologous to that of American ALV-J strains. To our knowledge, this is the first report of the isolation, complete genome sequencing, and systematic molecular epidemiological investigation of ALV-J in Pakistan. Our findings could enrich epidemiological data and might contributed to more effective measures to prevent and control avian leukosis in Pakistan.
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Vírus da Leucose Aviária/classificação , Vírus da Leucose Aviária/genética , Leucose Aviária/virologia , Regiões 3' não Traduzidas , Animais , Leucose Aviária/patologia , Vírus da Leucose Aviária/isolamento & purificação , Linhagem Celular , Galinhas/virologia , DNA Viral , Epidemiologia Molecular , Paquistão/epidemiologia , Filogenia , Doenças das Aves Domésticas/virologia , Análise de Sequência de DNA , Proteínas do Envelope Viral/genética , Sequenciamento Completo do GenomaRESUMO
Semen Vaccariae, the seed of Vaccaria segetalis, is traditionally used in East Asian countries for the treatment of breast milk deficiency, but the underlying molecular mechanism has not been discovered yet. The present study assessed the stimulatory effect of vaccarin, one of the major constituents of Semen Vaccariae, on proliferation of and milk synthesis in bovine mammary epithelial cells (BMECs) and explored the corresponding molecular mechanism. Vaccarin affected cell proliferation and milk fat and protein synthesis in a concentration-dependent manner, with the best stimulatory effects at 0.5 µg/ml concentration. Vaccarin (0.5 µg/ml) had the similar effects as prolactin (Prl, 0.5 µg/ml) on cell proliferation, milk fat and protein synthesis, expression of Cyclin D1, phosphorylation of mechanistic target of rapamycin (mTOR), and expression and maturation of sterol regulatory element binding protein 1c (SREBP-1c). Vaccarin stimulated these signaling pathways via the Prl receptor-phosphatidyl inositol 3-kinase (PI3K) signaling. Vaccarin also concentration-dependently stimulated expression of the Prl receptor, with the best effects at 0.5 µg/ml concentration. In summary, we demonstrate that vaccarin promotes proliferation of and milk synthesis in BMECs through the Prl receptor-PI3K signaling, suggesting that vaccarin might be the main active component promoting milk production of BMECs in Semen Vaccariae.
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Células Epiteliais/efeitos dos fármacos , Flavonoides/farmacologia , Glicosídeos/farmacologia , Leite/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Receptores da Prolactina/metabolismo , Animais , Bovinos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/metabolismo , Feminino , Glândulas Mamárias Animais/citologia , Transdução de Sinais/efeitos dos fármacosRESUMO
The design of contrast agents (CAs) with high magnetic relaxivities is a key issue in the field of magnetic resonance imaging (MRI). The traditional strategy employed is aimed at optimizing the structural design of the magnetic atoms in the CA. However, it is difficult to obtain an agent with magnetic relaxivity over 100 mM-1 s-1 using this approach. In this work, we demonstrate that modulation of the localized superacid microenvironment of certain CAs (Gd3+ loaded polyethylene glycol modified graphene oxide quantum dots or 'GPG' for short) can effectively enhance the longitudinal magnetic relaxivities (r1) by accelerating proton exchange. r1 values of a series of GPGs are significantly increased by 20-30 folds compared to commercially available CAs over a wide range of static magnetic field strengths (e.g. 210.9 mM-1 s-1vs. 12.3 mM-1 s-1 at 114 µT, 127.0 mM-1 s-1vs. 4.9 mM-1 s-1 at 7.0 T). GPG aided MRI images is then acquired both in vitro and in vivo with low biotoxicities. Furthermore, folic-acid-modified GPG is demonstrated suitable for MRI-fluorescence dual-modal tumor targeting imaging in animals with more than 98.3% specific cellular uptake rate.
Assuntos
Grafite , Neoplasias , Pontos Quânticos , Animais , Meios de Contraste , Imageamento por Ressonância Magnética , Microambiente TumoralRESUMO
BACKGROUND: To investigate the diagnostic performance of quantified plaque analysis and high-risk plaque characterization by coronary computed tomography angiography (CCTA) for identifying thin-cap fibroatheroma (TCFA). METHODS: Patients who underwent both CCTA and intravascular ultrasound (IVUS) within 4 weeks were retrospectively included. CT-derived quantitative and qualitative parameters, including diameter stenosis, minimal lumen area (MLA), low attenuation plaque (LAP) volume napkin-ring sign (NRS), positive remodeling (PR) and spotty calcification, were recorded. TCFA lesions and non-TCFA lesions were determined by IVUS. Multivariate regression analysis was used to determine the independent predictors of TCFA lesions. RESULTS: Sixty-five patients (mean age: 69.8±9.2 years, 29 females) with 89 lesions were finally included. LAP and NRS were more frequently presented in the group of TCFA lesions. The mean LAP volume of TCFA lesions was significantly larger than that of non-TCFA lesions [16.5 (11.0-23.0) vs. 0 (0-1.5) mm3, P<0.001]. According to multivariate logistic regression analysis, LAP volume was the only significant predictor for IVUS-confirmed vulnerable plaques (odds ratio =3.294, 95% confidence interval: 1.177-9.223, P=0.023). LAP volume showed largest area under curve (AUC) for diagnosing TCFA lesions (AUC =0.901, 95% confidence interval: 0.819-0.954, P<0.0001). When using >8 mm3 as the best cutoff value, the diagnostic accuracy, sensitivity and specificity of LAP volume for predicting TCFA lesions were 91.0% (81/89), 84.6% (22/26) and 96.8% (61/63) respectively. CONCLUSIONS: CT-derived LAP volume of TCFA lesions was significantly higher than those of non-TCFA lesions. LAP volume was the strongest predictor for TCFA lesions as validated by IVUS.
RESUMO
The CRISPR/CRISPR-associated protein 9 (Cas9) system is a powerful gene-editing tool originally discovered as an integral mediator of bacterial adaptive immunity. Recently, this technology has been explored for its potential utility in providing new and unique treatments for viral infection. Marek's disease virus (MDV) and avian leukosis virus subgroup J (ALV-J), major immunosuppressive viruses, cause significant economic losses to the chicken industry. Here, we evaluated the efficacy of using MDV as a CRISPR/Cas9-delivery system to directly target and disrupt the reverse-transcribed products of the ALV-J RNA genome during its infection cycle in vitro and in vivo. We first screened multiple potential guide RNA (gRNA) target sites in the ALV-J genome and identified several optimized targets capable of effectively disrupting the latently integrated viral genome and providing efficient defense against new infection by ALV-J in cells. The optimal single-gRNAs and Cas9-expression cassettes were inserted into the genome of an MDV vaccine strain. The results indicated that engineered MDV stably expressing ALV-J-targeting CRISPR/Cas9 efï¬ciently resisted ALV-J challenge in host cells. These findings demonstrated the CRISPR/Cas9 system as an effective treatment strategy against ALV-J infection. Furthermore, the results highlighted the potential of MDV as an effective delivery system for CRISPR/Cas9 in chickens.