RESUMO
Bergamot essential oil (BEO) is an extract of the bergamot fruit with significant neuroprotective effect. This study was to investigate the effects and the underlying mechanism of BEO in mitigating depression. GC-MS were used to identify its constituents. Antidepressive properties of BEO were evaluated by sucrose preference test (SPT), force swimming test (FST) and open field test (OFT). Nissl staining was used to determine the number of Nissl bodies in hippocampus (HIPP) of rats. Changes in HIPP dendritic length and dendritic spine density were detected by Golgi-Cox staining. Immunohistochemistry and Western blot were used to detect the postsynaptic density protein-95 (PSD-95) and synaptophysin (SYP) in the HIPP of rats. The enzyme-linked immunosorbent assay was used to determine the 5-hydroxytryptamine (5-HT), insulin-like growth factor 1 (IGF-1) and interleukin-1ß (IL-1ß) in the HIPP, serum and cerebrospinal fluid (CSF) of rats. Inhaled BEO significantly improved depressive behaviour in chronic unpredictable mild stress (CUMS) rats. BEO increased Nissl bodies, dendritic length and spine density, PSD-95 and SYP protein in the HIPP. Additionally, BEO upregulated serum 5-HT, serum and CSF IGF-1, while downregulating serum IL-1ß. Collectively, inhaled BEO mitigates depression by protecting the plasticity of hippocampal neurons, hence, providing novel insights into treatment of depression.
Assuntos
Depressão , Óleos Voláteis , Ratos , Animais , Depressão/tratamento farmacológico , Depressão/etiologia , Depressão/metabolismo , Óleos Voláteis/farmacologia , Óleos Voláteis/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Serotonina/metabolismo , Hipocampo/metabolismo , Proteína 4 Homóloga a Disks-Large/metabolismo , Neurônios/metabolismo , Estresse Psicológico/complicações , Estresse Psicológico/tratamento farmacológico , Modelos Animais de Doenças , Comportamento AnimalRESUMO
Photo-responsive adsorption has emerged as a vibrant area because it provides a promising route to reduce the energy consumption of the traditional adsorption separation. However, the current methodology to fabricate photo-responsive sorbents is still subject to the photo-deforming molecular units. In this study, a new initiative of photo-dissociated electron-hole pairs is proposed to generate amazing adsorption activity, and prove its feasibility. Employing CuPP [PP = 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin] framework nanosheets compounded with graphene, binary film (BF) sorbents are successfully fabricated. The paradigmatic BF nanostructure brings about efficiently photo-excited electron-hole pairs with durable enough lifetime to meet the needs of microscopic adsorption equilibrium, which ultimately alters the electron density distribution of adsorption surface, and thus markedly modulates the adsorption activity. Therefore, an amazing photo-enhanced adsorption capability for the index gas CO can be gotten. Once exposed to the visible-light at 420 nm, the CO adsorption capacity (0 °C, 1 bar) is risen from 0.23 mmol g-1 in the darkness to 1.66 mmol g-1, changed by + 622%. This is essentially different from majority of current photo-responsive sorbents based on photo-deforming molecular units, of which adsorption capability is only decreased with photo-induction, and the maximum rate of change reported is just -54%.
RESUMO
OBJECTIVES: To assess the predictive value of different dosimetric parameters for acute radiation oral mucositis (ROM) in head and neck cancer (HNCs) patients treated with carbon-ion radiotherapy (CIRT). METHODS: 44 patients with HNCs treated with CIRT were evaluated for acute ROM which was defined as severe when the score ≥3 (acute ROM was scored prospectively using the Radiation Therapy Oncology Group (RTOG) score system). Predictive dosimetric factors were identified by using univariate and multivariate analysis. RESULTS: Male gender, weight loss >5%, and total dose/fractions were related factors to severe ROM. In multivariate analysis, grade ≥3 ROM was significantly related to the Dmax, D10, D15, and D20 (Pâ¯< 0.05, respectively). As the receiver operating characteristics (ROC) curve shows, the area under the curve (AUC) for D10 was 0.77 (pâ¯= 0.003), and the cutoff value was 51.06â¯Gy (RBE); The AUC for D15 was 0.75 (pâ¯= 0.006), and the cutoff value was 42.82â¯Gy (RBE); The AUC for D20 was 0.74 (pâ¯= 0.009), and the cutoff value was 30.45â¯Gy (RBE); The AUC for Dmax was 0.81 (pâ¯< 0.001), and the cutoff value was 69.33â¯Gy (RBE). CONCLUSION: Male gender, weight loss, and total dose/fractions were significantly association with ROM. Dmax, D10, D15 and D20 were identified as the most valuable predictor and we suggest a Dmax limit of 69.33â¯Gy (RBE), D10 limit of 51.06â¯Gy (RBE), D15 limit of 42.82â¯Gy (RBE), and D20 limit of 30.45â¯Gy (RBE) and for oral mucosa.
Assuntos
Radioterapia com Íons Pesados , Lesões por Radiação , Dosagem Radioterapêutica , Estomatite , Humanos , Masculino , Feminino , Estomatite/etiologia , Estomatite/radioterapia , Pessoa de Meia-Idade , Idoso , Radioterapia com Íons Pesados/efeitos adversos , Lesões por Radiação/etiologia , Adulto , Neoplasias de Cabeça e Pescoço/radioterapia , Idoso de 80 Anos ou mais , Doença Aguda , Redução de Peso/efeitos da radiação , Resultado do Tratamento , Fatores de RiscoRESUMO
Macrophages are multifunctional innate immune cells that play indispensable roles in homeostasis, tissue repair, and immune regulation. However, dysregulated activation of macrophages is implicated in the pathogenesis of various human disorders, making them a potential target for treatment. Through the expression of pattern recognition and scavenger receptors, macrophages exhibit selective uptake of pathogens and apoptotic cells. Consequently, the utilization of drug carriers that mimic pathogenic or apoptotic signals shows potential for targeted delivery to macrophages. In this study, a series of mannosylated or/and phosphatidylserine (PS) -presenting liposomes were developed to target macrophages via the design of experiment (DoE) strategy and the trial-and-error (TaE) approach. The optimal molar ratio for the liposome formulation was DOPC: DSPS: Chol: PEG-PE = 20:60:20:2 based on the results of cellular uptake and cytotoxicity evaluation on RAW 264.7 and THP-1 in vitro. Results from in vivo distribution showed that, in the DSS-induced colitis model and collagen II-induced rheumatoid arthritis model, PS-presenting liposomes (PS-Lipo) showed the highest accumulation in intestine and paws respectively, which holds promising potential for macrophage target therapy since macrophages are abundant at inflammatory sites and contribute to the progression of corresponding diseases. Organs such as the heart, liver, spleen, lung, and kidney did not exhibit histological alterations such as inflammation or necrosis when exposed to PC-presenting liposomes (PC-Lipo) or PS-Lipo. In addition, liposomes demonstrated hemobiocompatibility and no toxicity to liver or kidney for circulation and did not induce metabolic injury in the animals. Thus, the well-designed PS-Lipo demonstrated the most potential for macrophage target therapy.
Assuntos
Apoptose , Lipossomos , Macrófagos , Fosfatidilserinas , Lipossomos/química , Animais , Camundongos , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Humanos , Células RAW 264.7 , Fosfatidilserinas/metabolismo , Fosfatidilserinas/química , Células THP-1 , Masculino , Camundongos Endogâmicos C57BL , Sistemas de Liberação de Medicamentos/métodos , Distribuição TecidualRESUMO
BACKGROUND: The objective of this study is to assess the association between age and lymph nodes metastasis (LNM) in T1 tonsil squamous cell carcinomas (TSCC) patients. METHODS: Patients with T1 TSCC were extracted from the SEER database between 2005 and 2014. Univariate and multivariate logistic regression models were produced to recognize the association between age and risk factors of LNM. RESULTS: A total of 2430 patients were analyzed. Younger patients more frequently presented with LNM compared to their older peers (P < 0.01, respectively.). In multivariate analyses, older age was associated with a significantly lower risk of LNM. Compared to patients aged 29-39-years-old, the hazard ratios for patients aged 40-49, 50-59, 60-69, and 70-88 years old were 0.911 (95 % confidence interval [CI] 0.370-2.245), 0.641 (95 % CI 0.268-1.535), 0.511 (95 % CI 0.212-1.231), and 0.236 (95 % CI 0.095-0.584), respectively. Subgroups analysis shows that the effect of older age was significantly associated with a lower risk of LNM in all groups except for Asian patients (P < 0.05, respectively). CONCLUSION: Our study demonstrates that younger patients with T1 TSCC had a higher risk of LNM than their old peers and the effect of older age was significantly associated with a lower risk of LNM in all groups except for Asian patients. More accurate assessments of LNM and prophylactic neck dissection or prophylactic adjuvant radiation therapy to neck will be imperative for reducing recurrence in younger T1 TSCC.
RESUMO
Sleep deprivation (SD) is prevalent throughout the world, which has negative effects on cognitive abilities, and causing mood alterations. 8-O-acetyl shanzhiside methylester (8-OaS), a chief component in Lamiophlomis rotata (L. rotata) Kudo, possesses potent neuroprotective properties and analgesic effects. Here, we evaluated the alleviative effects of 8-OaS on memory impairment and anxiety in mice subjected to SD (for 72-h). Our results demonstrated that 8-OaS (0.2, 2, 20 mg/kg) administration dose-dependently ameliorated behavioral abnormalities in SD mice, accompanied with restored synaptic plasticity and reduced shrinkage and loss of hippocampal neurons. 8-OaS reduced the inflammatory response and oxidative stress injury in hippocampus caused by SD, which may be related to inhibition of NLRP3 inflammasome-mediated inflammatory process and activation of the Nrf2/HO-1 pathway. SD also led to increases in the expressions of TLR-4/MyD88, active NF-κB, pro-IL-1ß, TNFα and MDA, as well as a decrease in the level of SOD in mice hippocampus, which were reversed by 8-OaS administration. Moreover, our molecular docking analyses showed that 8-OaS also has good affinity for NLRP3 and Nrf2 signaling pathways. These results suggested that 8-OaS could be used as a novel herbal medicine for the treatment of sleep loss and for use as a structural base for developing new drugs.
Assuntos
Proteína 3 que Contém Domínio de Pirina da Família NLR , Privação do Sono , Animais , Camundongos , Ansiedade/tratamento farmacológico , Ansiedade/etiologia , Cognição , Simulação de Acoplamento Molecular , Fator 2 Relacionado a NF-E2/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Privação do Sono/complicações , Privação do Sono/tratamento farmacológicoRESUMO
OBJECTIVES: To analyze the risk factors for synchronous lung metastases (LM) in patients with major salivary gland mucoepidermoid carcinoma (MaSG-MEC). METHODS: MaSG-MEC patients were extracted from the Surveillance, Epidemiology and End Results (SEER) database between 2010 and 2014. Descriptive statistics were used to examine the baseline characteristics of the patients. We examined the association between risk factors and synchronous LM using Chi-squared tests. The primary study outcomes were overall survival (OS) and cancer-specific survival (CSS). Kaplan-Meier survival curves were compared using the log-rank test. Hazard analysis was conducted using the Cox proportional hazards model. RESULTS: A total of 701 patients were analyzed, which including 8 patients (1.1%) with synchronous LM, and 693 patients without synchronous LM (98.9%). Lower T or N classification, and highly differentiated disease were associated with a significantly lower risk of LM and multivariate logistic regression analysis showed that lower T classification were associated with a significantly lower risk of LM (P < 0.05, respectively). Elderly Caucasian male patients with poorly differentiated disease, multiple sites of metastases and no surgical therapy to primary tumor were more likely to reduce life expectancy. CONCLUSION: By analyzing data from a large cohort, lower T or N classification and highly differentiated disease were associated with a significantly lower risk of LM. Elderly Caucasian male patients with poorly differentiated disease, multiple sites of metastases and no surgical therapy to primary tumor were more likely to reduce life expectancy. More accurate assessments of LM will be imperative for early diagnosis and treatment in patients who harbored with higher T or N classification and poorly differentiated disease.
Assuntos
Carcinoma Mucoepidermoide , Neoplasias Pulmonares , Neoplasias das Glândulas Salivares , Humanos , Masculino , Idoso , Carcinoma Mucoepidermoide/epidemiologia , Carcinoma Mucoepidermoide/patologia , Prognóstico , Neoplasias das Glândulas Salivares/patologia , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/patologia , Glândulas Salivares/patologiaRESUMO
BACKGROUND: To analyze the risk factors for synchronous bone metastases (BM) in patients with tonsillar squamous cell carcinomas. METHODS: Tonsillar carcinomas patients were extracted from the Surveillance, Epidemiology and End Results (SEER) database between 2010 and 2013. We examined the association between risk factors and synchronous BM using Chi-squared tests. Predictors of survival rates were assessed using univariate and multivariate analyses. RESULTS: A total of 5752 patients were analyzed, which including 35 patients (0.6%) with synchronous BM, and 5717 patients without synchronous BM (99.4%). Multivariate logistic regression analysis showed that Caucasian, lower T or N classification were associated with a significantly lower risk of BM (P < 0.05, respectively). Elderly not married non-Caucasian patients with highly differentiated disease, higher T or N classification, multiple sites of metastases and no surgical therapy to primary tumor were more likely to reduce life expectancy. CONCLUSIONS: By analyzing data from a large cohort, Caucasian, lower T or N classification were associated with a significantly lower risk of BM. Elderly not married non-Caucasian patients with highly differentiated disease, higher T or N classification, multiple sites of metastases and no surgical therapy to primary tumor were more likely to reduce life expectancy. More accurate assessments of BM will be imperative for early diagnosis and treatment in non-Caucasian tonsillar carcinoma patients who harbored with higher T or N classification.
Assuntos
Neoplasias Ósseas , Carcinoma de Células Escamosas , Humanos , Idoso , Neoplasias Ósseas/secundário , Análise Multivariada , Fatores de Risco , Carcinoma de Células Escamosas/patologia , Prognóstico , Estudos RetrospectivosRESUMO
CHD7, an encoding ATP-dependent chromodomain helicase DNA-binding protein 7, has been identified as the causative gene involved in CHARGE syndrome (Coloboma of the eye, Heart defects, Atresia choanae, Retardation of growth and/or development, Genital abnormalities and Ear abnormalities). Although studies in rodent models have expanded our understanding of CHD7, its role in oligodendrocyte (OL) differentiation and myelination in zebrafish is still unclear. In this study, we generated a chd7-knockout strain with CRISPR/Cas9 in zebrafish. We observed that knockout (KO) of chd7 intensely impeded the oligodendrocyte progenitor cells' (OPCs) migration and myelin formation due to massive expression of chd7 in oilg2+ cells, which might provoke upregulation of the MAPK signal pathway. Thus, our study demonstrates that chd7 is critical to oligodendrocyte migration and myelination during early development in zebrafish and describes a mechanism potentially associated with CHARGE syndrome.
Assuntos
Síndrome CHARGE , Células Precursoras de Oligodendrócitos , Animais , Diferenciação Celular/genética , Síndrome CHARGE/genética , DNA Helicases/genética , Oligodendroglia , Peixe-Zebra/genéticaRESUMO
OBJECTIVE: To retrospectively analyze the screening results for genetic metabolic diseases among newborns from Changsha in order to determine the prevalence of single diseases and their mutational spectrum. METHODS: 352 449 neonates born from January 2016 to December 2021 in Changsha were subjected to tandem mass spectrometry. Suspected cases were further analyzed by biochemical and genetic testing. RESULTS: Among the 352 449 newborns, 6 170 were positive for the screening, which yielded a positive rate of 1.75%. 5 437 cases were recalled, and 92 were confirmed, with the overall prevalence being 1â¶3 831 and positive predictive value of 1.69%. Eighteen genetic metabolic diseases were detected among the 92 children, including 33 amino acid metabolic disorders, among which 20 were phenylalanine hydroxylase deficiency (60.60%). 17 cases had organic acid metabolic disorders, among which 4 were 2-methyl-dehydrogenase deficiency (23.50%). 42 had fatty acid metabolic disorders, among which 27 (64.30%) were primary carnitine deficiency and 12 were short-chain acyl-CoA dehydrogenase deficiency (28.60%). In total 90 genetic variants were identified, with the most common ones including c.51C>G, c.1400C>G, c.760C>T, c.1031A>G and c.1165A>G. CONCLUSION: The common neonatal genetic metabolic diseases in Changsha include primary carnitine deficiency, phenylalanine hydroxylase deficiency and short-chain acyl-CoA dehydrogenase deficiency. The preliminary delineation of mutational spectrum for genetic metabolic diseases in Changsha can facilitate early diagnosis and intervention, so as to improve the quality of newborn population.
Assuntos
Erros Inatos do Metabolismo Lipídico , Doenças Metabólicas , Fenilcetonúrias , Recém-Nascido , Criança , Humanos , Estudos Retrospectivos , Doenças Metabólicas/diagnóstico , Doenças Metabólicas/genética , Erros Inatos do Metabolismo Lipídico/diagnóstico , Erros Inatos do Metabolismo Lipídico/genética , Fenilcetonúrias/diagnóstico , Fenilcetonúrias/genéticaRESUMO
Antimicrobial susceptibility testing (AST) is an effective way to guide antibiotic selection. However, conventional culture-based phenotypic AST is time-consuming. The key point to shorten the test is to quantify the small change in the bacterial number after the antibiotic exposure. To achieve rapid AST, we proposed a combination of multiplexed PCR with barcoded pyrosequencing to significantly shorten the time for antibiotic exposure. First, bacteria exposed to each antibiotic were labeled with a unique barcode. Then, the pool of the barcoded products was amplified by PCR with a universal primer pair. Finally, barcodes in the amplicons were individually and quantitatively decoded by pyrosequencing. As pyrosequencing is able to discriminate as low as 5% variation in target concentrations, as short as 7.5 min was enough for cultivation to detect the susceptibility of Escherichia coli to an antibiotic. The barcodes enable more than six kinds of drugs or six kinds of concentrations of a drug to be tested at a time. The susceptibility of 6 antibiotics to 43 E. coli-positive samples from 482 clinical urine samples showed a consistency of 99.3% for drug-resistant samples and of 95.7% for drug-sensitive samples in comparison with the conventional method. In addition, the minimum inhibitory concentration (MIC) of 29 E. coli samples was successfully measured. The proposed AST is dye free (pyrosequencing), multiplexed (six antibiotics), fast (a half-working day for reporting the results), and able to detect the MIC, thus having a great potential for clinical use in quick antibiotic selection.
Assuntos
Antibacterianos , Infecções por Escherichia coli , Antibacterianos/farmacologia , Bactérias , Escherichia coli/genética , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Testes de Sensibilidade MicrobianaRESUMO
Cancer-derived exosomes carry a variety of important biomarkers specific to the formation, invasion and metastasis of tumor tissue. Dynamic monitoring of exosomes originated from cancer cells has clinical significance. Here we proposed a novel method to employ zirconium-metal-organic frameworks (Zr-MOFs) for extracting and identifying exosomes from blood. At first UiO-66 was magnetically modified as the adsorbent to anchor exosomes by forming Zr-O-P bonds. Then UiO-66-NH2 modified with anti-EpCAM was used to construct the fluorescent probe to recognize the extracted EpCAM-positive exosomes by forming a "MOF-exosome-MOF" structure. The proposed fluorescence detection method was evaluated by quantifying MCF-7 cell-derived exosomes at the concentration as low as 16.72 particles/µl. This method was successfully applied to analyze exosomes in the plasma samples from healthy donors and breast cancer patients, demonstrating that our method might have a great potential in assisting the early diagnosis and in dynamically monitoring the efficacy of cancer treatment. We believe that the method could be extended to the detection of other biomarkers in exosomes derived from cancer cell.
Assuntos
Exossomos , Estruturas Metalorgânicas , Neoplasias , Fluorescência , Humanos , Lipídeos , Estruturas Metalorgânicas/química , Ácidos Ftálicos , Zircônio/químicaRESUMO
BACKGROUND: Tim-3/Galectin-9 is involved in the immune escape of many pathogens. However, the role of Tim-3/Galectin-9 in persistent infection of Echinococcus multilocularis (Em), which is related to immune escape, is still unclear. OBJECTIVE: To investigate the role of Tim-3/Galectin-9 and related cytokines in mice with persistent infection of Em. METHODS: Em infection model was established by injecting the protoscoleces. Serum was collected at days 2, 8, 30, 60, 90, 180 and 270 after infection. Lymphocytes were isolated from liver tissue samples with Ficoll. Tim-3 + CD4 + T percentage was analyzed by flow cytometry. CD4 + T cells were isolated from liver tissues of Em infected mice and cultured in vitro. The mRNA levels of Tim-3, Galectin-9, IFN-γ and IL-4 were detected by qRT-PCR. Cytokine levels in serum and culture supernatant (IFN-γ and IL-4) were analyzed by cytometric bead array. RESULTS: The expression of Tim-3 and Galectin-9 mRNA significantly increased after 30 days of infection, reached peak on day 90, and then decreased slightly on days 180-270. The expression of IFN-γ mRNA, increased on day 2 and 8 after infection, slightly decreased on days 30-60, and obvious decreased on days 90-270, but were still higher than those of the control group. The expression of IL-4 mRNA gradually increased along with the time of infection. In serum of Em infected mice, level of IFN-γ peaked at day 30 and then gradually decreased; whereas IL-4 level peaked at day 90 and then gradually decreased. In vitro experiment found that Tim-3/Galectin-9 directly caused the changes in the levels of IFN-γ and IL-4. CONCLUSIONS: Tim-3/Galectin-9 signaling pathway may be involved in the development of persistent infection of Em by regulating the production of Th1 and Th2 cytokines.
Assuntos
Citocinas , Receptor Celular 2 do Vírus da Hepatite A , Animais , Equinococose , Galectinas/genética , Receptor Celular 2 do Vírus da Hepatite A/genética , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Interleucina-4/genética , Camundongos , RNA Mensageiro/metabolismo , Transdução de SinaisRESUMO
Background: To determine suitable optimal classifiers and examine the general applicability of computer-aided classification to compare the differences between a computer-aided system and radiologists in predicting pathological complete response (pCR) from patients with breast cancer receiving neoadjuvant chemotherapy. Methods: We analyzed a total of 455 masses and used the U-Net network and ResNet to execute MRI segmentation and pCR classification. The diagnostic performance of radiologists, the computer-aided system and a combination of radiologists and computer-aided system were compared using receiver operating characteristic curve analysis. Results: The combination of radiologists and computer-aided system had the best performance for predicting pCR with an area under the curve (AUC) value of 0.899, significantly higher than that of radiologists alone (AUC: 0.700) and computer-aided system alone (AUC: 0.835). Conclusion: An automated classification system is feasible to predict the pCR to neoadjuvant chemotherapy in patients with breast cancer and can complement MRI.
Assuntos
Neoplasias da Mama/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Terapia Neoadjuvante , Radiologistas , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/tratamento farmacológico , Feminino , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Estudos RetrospectivosRESUMO
Marine macroalgae, contributing much to the bioeconomy, have inspired tremendous attention as sustainable raw materials. Ulvan, as one of the main structural components of green algae cell walls, can be degraded by ulvan lyase through the ß-elimination mechanism to obtain oligosaccharides exhibiting several good physiological activities. Only a few ulvan lyases have been characterized until now. This thesis explores the properties of a new polysaccharide lyase family 25 ulvan lyase TsUly25B from the marine bacterium Thalassomonas sp. LD5. Its protein molecular weight was 54.54 KDa, and it was most active under the conditions of 60 °C and pH 9.0. The Km and kcat values were 1.01 ± 0.05 mg/mL and 10.52 ± 0.28 s-1, respectively. TsUly25B was salt-tolerant and NaCl can significantly improve its thermal stability. Over 80% of activity can be preserved after being incubated at 30 °C for two days when the concentration of NaCl in the solution is above 1 M, while 60% can be preserved after incubation at 40 °C for 10 h with 2 M NaCl. TsUly25B adopted an endolytic manner to degrade ulvan polysaccharides, and the main end-products were unsaturated ulvan disaccharides and tetrasaccharides. In conclusion, our research enriches the ulvan lyase library and advances the utilization of ulvan lyases in further fundamental research as well as ulvan oligosaccharides production.
Assuntos
Proteínas de Bactérias , Gammaproteobacteria/enzimologia , Polissacarídeo-Liases , Polissacarídeos/química , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Escherichia coli/genética , Gammaproteobacteria/genética , Conformação Molecular , Filogenia , Polissacarídeo-Liases/química , Polissacarídeo-Liases/genética , Polissacarídeo-Liases/isolamento & purificação , Proteínas Recombinantes/química , Cloreto de Sódio/químicaRESUMO
A high enzyme-yield strain Yersinia sp. 298 was screened from marine bacteria harvested from the coastal water. The screening conditions were extensive, utilizing hyaluronic acid (HA)/chondroitin sulfate (CS) as the carbon source. A coding gene yshyl8A of the family 8 polysaccharide lyase (PL8) was cloned from the genome of Yersinia sp. 298 and subjected to recombinant expression. The specific activity of the recombinase YsHyl8A was 11.19 U/mg, with an optimal reaction temperature of 40 °C and 50% of its specific activity remaining after thermal incubation at 30 °C for 1 h. In addition, its optimal reaction pH was 7.5, and while it was most stable at pH 6.0 in Na2HPO4-citric acid buffer, it remained highly stable at pH 6.0-11.0. Further, its enzymatic activity was increased five-fold with 0.1 M NaCl. YsHyl8A, as an endo-lyase, can degrade both HA and CS, producing disaccharide end-products. These properties suggested that YsHyl8A possessed both significant alkalophilic and cold-adapted features while being dependent on NaCl, likely resulting from its marine source. Yersinia is a typical fish pathogen, with glycosaminoglycan lyase (GAG lyase) as a potential pathogenic factor, exhibiting strong hyaluronidase and chondroitinase activity. Further research on the pathogenic mechanism of GAG lyase may benefit the prevention and treatment of related diseases.
Assuntos
Glicosaminoglicanos , Liases , Animais , Sulfatos de Condroitina , Ácido Hialurônico/química , Concentração de Íons de Hidrogênio , Polissacarídeo-Liases/química , Cloreto de Sódio , Yersinia/genética , Yersinia/metabolismoRESUMO
Collective interstitial ordering is at the core of martensite formation in Fe-C-based alloys, laying the foundation for high-strength steels. Even though this ordering has been studied extensively for more than a century, some fundamental mechanisms remain elusive. Here, we show the unexpected effects of two correlated phenomena on the ordering mechanism: anharmonicity and segregation. The local anharmonicity in the strain fields induced by interstitials substantially reduces the critical concentration for interstitial ordering, up to a factor of three. Further, the competition between interstitial ordering and segregation results in an effective decrease of interstitial segregation into extended defects for high interstitial concentrations. The mechanism and corresponding impact on interstitial ordering identified here enrich the theory of phase transitions in materials and constitute a crucial step in the design of ultra-high-performance alloys.
RESUMO
Hypoxia can promote the progression and metastasis of ovarian cancer, while the underlying mechanisms are still unclear. Hypoxia culture or CoCl2 induced-oxygen deprivation condition could promote SKOV3 cells to express cyclooxygenase-2 (COX2). Luciferase assay indicates that hypoxia-inducible factor 1α (HIF1α) could bind directly with the promoter region of COX2 to promote the transcription. COX2 over-expressed SKOV3 cells show up-regulated stemness-related markers expression, proinflammatory gene expression, and increased tumor sphere formation. The inflammatory molecules (interleukin-6, C-X-C motif chemokine ligand 12, interleukin-1B, interleukin-10, and C-C motif chemokine ligand 2) and COX2 expression show positive correlations in the Cancer Genome Atlas data. COX2 over-expression could promote SKOV3 cell proliferation in the subcutaneous tumor model and metastasis in the transfer model. In conclusion, hypoxia-induced HIF-1α mediated COX2 expression could promote the proliferation, inflammation, and metastasis of ovarian cancer.
Assuntos
Hipóxia Celular/genética , Ciclo-Oxigenase 2/efeitos adversos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Ovarianas/fisiopatologia , Animais , Progressão da Doença , Feminino , Humanos , Ratos , TransfecçãoRESUMO
Hyaluronate lyases have received extensive attention due to their applications in medical science, drug and biochemical engineering. However, few thermotolerant and pH-stable hyaluronate lyases have been found. In this study, hyaluronate lyase TcHly8B from Thermasporomyces composti DSM22891 was expressed in Escherichia coli BL21(DE3), purified, and characterized. Phylogenetic analysis revealed that TcHly8B belonged to a new subfamily in PL8. The molecular mass of recombinant TcHly8B determined by SDS-PAGE was approximately 86â¯kDa. The optimal temperature of TcHly8B was 70⯰C, which was higher than that of previously reported hyaluronate lyases. TcHly8B was very stable at temperatures from 0 to 60⯰C. The optimal pH of TcHly8B was 6.6. It could retain more than 80% of its original enzyme activity after incubation for 12â¯h in the pH range of 3.0-10.6. TcHly8B degraded hyaluronic acid into unsaturated disaccharides as the end products. The amino acid sequence and structure analysis of TcHly8B demonstrated that the amino acid composition and salt bridges might contribute to the thermostability of TcHly8B. Overall, this study provides an excellent example for the discovery of thermotolerant hyaluronate lyases and can be applied to the industrialized production and basic research of hyaluronate oligosaccharides.
Assuntos
Actinobacteria , Proteínas de Bactérias , Polissacarídeo-Liases , Actinobacteria/enzimologia , Actinobacteria/genética , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Estabilidade Enzimática , Escherichia coli/genética , Escherichia coli/metabolismo , Temperatura Alta , Concentração de Íons de Hidrogênio , Polissacarídeo-Liases/biossíntese , Polissacarídeo-Liases/química , Polissacarídeo-Liases/genética , Polissacarídeo-Liases/isolamento & purificação , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificaçãoRESUMO
Brucellosis is one of the most serious and widespread zoonotic diseases, which seriously threatens human health and the national economy. This study was based on the T/B dominant epitopes of Brucella outer membrane protein 22 (Omp22), outer membrane protein 19 (Omp19) and outer membrane protein 28 (Omp28), with bioinformatics methods to design a safe and effective multi-epitope vaccine. The amino acid sequences of the proteins were found in the National Center for Biotechnology Information (NCBI) database, and the signal peptides were predicted by the SignaIP-5.0 server. The surface accessibility and hydrophilic regions of proteins were analysed with the ProtScale software and the tertiary structure model of the proteins predicted by I-TASSER software and labelled with the UCSF Chimera software. The software COBEpro, SVMTriP and BepiPred were used to predict B cell epitopes of the proteins. SYFPEITHI, RANKpep and IEDB were employed to predict T cell epitopes of the proteins. The T/B dominant epitopes of three proteins were combined with HEYGAALEREAG and GGGS linkers, and carriers sequences linked to the N- and C-terminus of the vaccine construct with the help of EAAAK linkers. Finally, the tertiary structure and physical and chemical properties of the multi-epitope vaccine construct were analysed. The allergenicity, antigenicity and solubility of the multi-epitope vaccine construct were 7.37-11.30, 0.788 and 0.866, respectively. The Ramachandran diagram of the mock vaccine construct showed 96.0% residues within the favoured and allowed range. Collectively, our results showed that this multi-epitope vaccine construct has a high-quality structure and suitable characteristics, which may provide a theoretical basis for future laboratory experiments.