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1.
Plant Cell ; 34(8): 3088-3109, 2022 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-35639755

RESUMO

Rice false smut caused by Ustilaginoidea virens is emerging as a devastating disease of rice (Oryza sativa) worldwide; however, the molecular mechanisms underlying U. virens virulence and pathogenicity remain largely unknown. Here we demonstrate that the small cysteine-rich secreted protein SCRE6 in U. virens is translocated into host cells during infection as a virulence factor. Knockout of SCRE6 leads to attenuated U. virens virulence to rice. SCRE6 and its homologs in U. virens function as a novel family of mitogen-activated protein kinase phosphatases harboring no canonical phosphatase motif. SCRE6 interacts with and dephosphorylates the negative immune regulator OsMPK6 in rice, thus enhancing its stability and suppressing plant immunity. Ectopic expression of SCRE6 in transgenic rice promotes pathogen infection by suppressing the host immune responses. Our results reveal a previously unidentified fungal infection strategy in which the pathogen deploys a family of tyrosine phosphatases to stabilize a negative immune regulator in the host plant to facilitate its infection.


Assuntos
Oryza , Doenças das Plantas , Interações Hospedeiro-Patógeno/genética , Hypocreales , Oryza/genética , Oryza/microbiologia , Monoéster Fosfórico Hidrolases/genética , Doenças das Plantas/microbiologia , Imunidade Vegetal/genética
2.
BMC Public Health ; 24(1): 1481, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38831260

RESUMO

BACKGROUND: This hemodialysis center experienced the pandemic from December 2022 to January 2023. Therefore, we sought to describe the clinical characteristics and mortality outcomes in hemodialysis patients during this Omicron surge. METHODS: According to whether they are infected, they are divided into two groups: SARS-CoV-2-positive and SARS-CoV-2-negative. The SARS-CoV-2-positive group was divided into a survival group and a non-survival group for comparison. RESULTS: 366 of 457 hemodialysis patients were infected with SARS-CoV-2. The most common symptoms observed were fever (43.2%) and cough (29.8%), Followed by diarrhea (1.4%). Hemodialysis patients with hypertension were more susceptible to SARS-CoV-2 infection. The lymphocyte count, serum creatinine, serum potassium, and serum phosphorus in the SARS-CoV-2-positive group were significantly lower than those in the SARS-CoV-2-negative group. The all-cause mortality rate for infection with SARS-CoV-2 was 5.2%. Only 7 of 366 SARS-CoV-2-positive patients were admitted to the intensive care unit, but 6 of them died. Intensive care unit hospitalization rates were significantly higher in the non-survival group compared with the survival group. White blood cells count, neutrophil count, C-reactive protein, AST, and D-dimer in the non-survival group were higher than those in the survival group. The lymphocyte count, hemoglobin concentration, serum creatinine, serum albumin, serum phosphorus and parathyroid hormone in the non-survival group were lower than those in the survival group. Age > 65 years, elevated C-reactive protein and AST are independent risk factors for death. Finally, no significant difference in vaccination status was found between the SARS-CoV-2-positive group and the negative group. CONCLUSIONS: Hemodialysis patients are at high risk for SARS-CoV-2 infection. Ensuring the adequacy of hemodialysis treatment and maintaining good physical condition of patients are the top priorities.


Assuntos
COVID-19 , Diálise Renal , SARS-CoV-2 , Humanos , COVID-19/mortalidade , COVID-19/terapia , COVID-19/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Adulto , Falência Renal Crônica/terapia , Falência Renal Crônica/mortalidade , Hospitalização/estatística & dados numéricos
3.
Nanotechnology ; 35(9)2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37995375

RESUMO

Polyethylene glycol (PEG) is widely used as a phase change material (PCM) in thermal energy storage systems due to its high latent heat and chemical stability. However, practical application has been hindered by its low thermal conductivity and leakage issues. Therefore, developing shape-stable high thermal conductivity PCM is of great importance. In this study, new shape-stable composite PCM with high thermal conductivity and leak-prevention capabilities were designed. The porous carbon skeleton of diamond foam (DF) and dual-3D carbon nanotube-diamond foam (CDF) were prepared using the microwave plasma chemical vapor deposition method. The composite materials (DF/PEG and CDF/PEG) were produced by vacuum impregnation with PEG and skeletons. The results showed that CDF/PEG had the highest thermal conductivity, measuring 2.30 W·m-1·K-1, which is 707% higher than that of pure PEG. The employing of 3D networks of CNTs, which can improve the phonon mean free path in DF/PEG (1.79 W·m-1·K-1) while reducing phonon dispersion.The phonon vibration of dual-3D CDF plays an important role in heat transfer. PEG was physically absorbed and well-distributed in CDF, alleviating leakage of liquid PEG. The weight loss of CDF/PEG was only 25% at 70 °C for 120 s. Using CDF is an attractive and efficient strategy to increase the heat transfer of PEG and improve heat storage efficiency, alleviate the problem of poor shape-stability.

4.
J Integr Plant Biol ; 65(10): 2380-2394, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37534615

RESUMO

Mitogen-activated protein kinase (MAPK) cascades play pivotal roles in plant defense against phytopathogens downstream of immune receptor complexes. The amplitude and duration of MAPK activation must be strictly controlled, but the underlying mechanism remains unclear. Here, we identified Arabidopsis CPL1 (C-terminal domain phosphatase-like 1) as a negative regulator of microbe-associated molecular pattern (MAMP)-triggered immunity via a forward-genetic screen. Disruption of CPL1 significantly enhanced plant resistance to Pseudomonas pathogens induced by the bacterial peptide flg22. Furthermore, flg22-induced MPK3/MPK4/MPK6 phosphorylation was dramatically elevated in cpl1 mutants but severely impaired in CPL1 overexpression lines, suggesting that CPL1 might interfere with flg22-induced MAPK activation. Indeed, CPL1 directly interacted with MPK3 and MPK6, as well as the upstream MKK4 and MKK5. A firefly luciferase-based complementation assay indicated that the interaction between MKK4/MKK5 and MPK3/MPK6 was significantly reduced in the presence of CPL1. These results suggest that CPL1 plays a novel regulatory role in suppressing MAMP-induced MAPK cascade activation and MAMP-triggered immunity to bacterial pathogens.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas Quinases Ativadas por Mitógeno/genética , Arabidopsis/metabolismo , RNA Polimerase II/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas de Arabidopsis/metabolismo , Monoéster Fosfórico Hidrolases/genética , Regulação da Expressão Gênica de Plantas , Imunidade Vegetal/genética , Fosfoproteínas Fosfatases/genética , Fatores de Transcrição/metabolismo , Proteínas de Ligação a RNA/metabolismo
5.
J Asian Nat Prod Res ; : 1-7, 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35611800

RESUMO

Two new cyclotrypyamine alkaloids equisetinines A and B, as well as three known alkaloids (3-5) were isolated from the stems of Ephedra equisetina Bunge. Their structures were characterized by spectroscopic methods, and the absolute configurations of the new compounds were determined by interpretation of their electronic circular dichroism. Anti-asthmatic activities of compounds were evaluated by releasing ß-Hex in C48/80-induced RBL-2H3 cells, and compound 5 exhibited significant anti-asthmatic activities.

6.
Molecules ; 27(15)2022 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-35897906

RESUMO

Four previously undescribed iridoid glycosides neocornuside A-D (1-4), along with six known ones (5-10), were isolated from Cornus officinalis fruit. Their structures were elucidated by extensive spectroscopic (NMR, UV, IR, and MS) analysis and comparison with data reported in the literature. All isolates were assessed for their antidiabetic activity on the relative glucose consumption in insulin-induced insulin-resistant HepG2 cells. The results showed that compounds 1, 3, and 7 exhibited significant antidiabetic activities with EC50 values of 0.582, 1.275, and 0.742 µM, respectively. Moreover, compounds 1, 3, and 7 could improve the ability of 2-NBDG uptake of insulin-induced HepG2 cells.


Assuntos
Cornus , Insulinas , Cornus/química , Frutas/química , Glicosídeos/química , Hipoglicemiantes/análise , Hipoglicemiantes/farmacologia , Insulinas/análise , Glicosídeos Iridoides/química
7.
Purinergic Signal ; 14(4): 359-369, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30084084

RESUMO

Painful diabetic neuropathy (PDN) is a common and troublesome diabetes complication. Protein kinase C (PKC)-mediated dorsal root ganglia (DRG) P2X3 receptor upregulation is one important mechanism underlying PDN. Accumulating evidence demonstrated that electroacupuncture (EA) at low frequency could effectively attenuate neuropathic pain. Our previous study showed that 2-Hz EA could relieve pain well in PDN. The study aimed to investigate whether 2-Hz EA relieves pain in PDN through suppressing PKC-mediated DRG P2X3 receptor upregulation. A 7-week feeding of high-fat and high-sugar diet plus a single injection of streptozotocin (STZ) in a dose of 35 mg/kg after a 5-week feeding of the diet successfully induced type 2 PDN in rats as revealed by the elevated body weight, fasting blood glucose, fasting insulin and insulin resistance, and the reduced paw withdrawal threshold (PWT), as well as the destructive ultrastructural change of sciatic nerve. DRG plasma membrane P2X3 receptor level and DRG PKC expression were elevated. Two-hertz EA failed to improve peripheral neuropathy; however, it reduced PWT, DRG plasma membrane P2X3 receptor level, and DRG PKC expression in PDN rats. Intraperitoneal administration of P2X3 receptor agonist αß-meATP or PKC activator phorbol 12-myristate 13-acetate (PMA) blocked 2-Hz EA analgesia. Furthermore, PMA administration increased DRG plasma membrane P2X3 receptor level in PDN rats subject to 2-Hz EA treatment. These findings together indicated that the analgesic effect of EA in PDN is mediated by suppressing PKC-dependent membrane P2X3 upregulation in DRG. EA at low frequency is a valuable approach for PDN control.


Assuntos
Gânglios Espinais/metabolismo , Neuralgia/metabolismo , Receptores de Quinase C Ativada/metabolismo , Receptores Purinérgicos P2X3/metabolismo , Animais , Diabetes Mellitus Experimental/metabolismo , Neuropatias Diabéticas/metabolismo , Antagonistas do Receptor Purinérgico P2X/farmacologia , Ratos Sprague-Dawley , Receptores de Quinase C Ativada/efeitos dos fármacos , Receptores Purinérgicos P2X3/efeitos dos fármacos , Regulação para Cima
8.
Am J Pathol ; 185(5): 1207-15, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25759266

RESUMO

Ischemic acute kidney injury is a serious untreatable condition. Activation of the G protein α12 (Gα12) subunit by reactive oxygen species is a major cause of tissue damage during renal ischemia-reperfusion injury. Kidney injury molecule-1 (KIM-1) is a transmembrane glycoprotein that is highly up-regulated during acute kidney injury, but the physiologic significance of this up-regulation is unclear. Here, we report for the first time that Kim-1 inhibits Gα12 activation and protects mice against renal ischemia-reperfusion injury. We reveal that Kim-1 physically interacts with and inhibits cellular Gα12 activation after inflammatory stimuli, including reactive oxygen species, by blocking GTP binding to Gα12. Compared with Kim-1(+/+) mice, Kim-1(-/-) mice exhibited greater Gα12 and downstream Src activation both in primary tubular epithelial cells after in vitro stimulation with H2O2 and in whole kidneys after unilateral renal artery clamping. Finally, we show that Kim-1-deficient mice had more severe kidney dysfunction and tissue damage after bilateral renal artery clamping, compared with wild-type mice. Our results suggest that KIM-1 is an endogenous protective mechanism against renal ischemia-reperfusion injury through inhibition of Gα12.


Assuntos
Injúria Renal Aguda/metabolismo , Subunidades alfa G12-G13 de Proteínas de Ligação ao GTP/metabolismo , Proteínas de Membrana/metabolismo , Traumatismo por Reperfusão/metabolismo , Injúria Renal Aguda/patologia , Animais , Western Blotting , Imunofluorescência , Receptor Celular 1 do Vírus da Hepatite A , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Confocal , Traumatismo por Reperfusão/patologia
9.
Cell Biol Int ; 40(4): 439-47, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26801333

RESUMO

The age-related changes in cell viability and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) play pivotal roles in the fracture healing process, especially in geriatric individuals. This study was designed to explore the age-related changes in murine BMSCs and the regulation of osteogenic differentiation in aged BMSCs in vitro. Notch signaling pathway took part in the regulation of osteogensis, while the relationship between Notch and the osteogenic differentiation in aged BMSCs has not been reported yet. BMSCs harvested from the bone marrow of young, adult, and aged C57BL/6 mice were cultured in osteogenic and adipogenic differentiation media. Histochemical staining results indicated that the osteogenic ability of BMSCs gradually decreased with aging, whereas the adipogenic ability increased. Cell activity assays showed that the proliferative and migrated capacity did not decline with aging significantly. According to real-time PCR and Western blotting results, the aged cells exhibited higher Notch signaling expression level than the younger ones did. After the aged BMSCs being treated with γ-secretase inhibitor, however, Notch activity was changed and the aging-imparied osteogenic ability reverted to a normal level. This study demonstrated that the decreased bone formation capacity in aged BMSCs had relationship with the transdifferentiation between osteogenesis and adipogenesis, which would be regulated by Notch signaling pathway and the attenuated osteogenesis in aged BMSCs could be promoted when the inhibition of Notch pathway.


Assuntos
Envelhecimento , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Receptores Notch/metabolismo , Transdução de Sinais/efeitos dos fármacos , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Western Blotting , Células da Medula Óssea/citologia , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Dipeptídeos/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Osteogênese/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real
10.
BMC Urol ; 16(1): 52, 2016 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-27578166

RESUMO

BACKGROUND: Methylation of the tumor suppressor gene H-cadherin (CDH13) has been reported in many cancers. However, the clinical effect of the CDH13 methylation status of patients with bladder cancer remains to be clarified. METHODS: A systematic literature search was performed to identify eligible studies in the PubMed, Embase, EBSCO, CKNI and Wanfang databases. The pooled odds ratio (OR) and the corresponding 95 % confidence interval (95 % CI) was calculated and summarized. RESULTS: Nine eligible studies were included in the present meta-analysis consisting of a total of 1017 bladder cancer patients and 265 non-tumor controls. A significant association was found between CDH13 methylation levels and bladder cancer (OR = 21.71, P < 0.001). The results of subgroup analyses based on sample type suggested that CDH13 methylation was significantly associated with bladder cancer risk in both the tissue and the urine (OR = 53.94, P < 0.001; OR = 7.71, P < 0.001; respectively). A subgroup analysis based on ethnic population showed that the OR value of methylated CDH13 was higher in Asians than in Caucasians (OR = 35.18, P < 0.001; OR = 8.86, P < 0.001; respectively). The relationships between CDH13 methylation and clinicopathological features were also analyzed. A significant association was not observed between CDH13 methylation status and gender (P = 0.053). Our results revealed that CDH13 methylation was significantly associated with high-grade bladder cancer, multiple bladder cancer and muscle invasive bladder cancer (OR = 2.22, P < 0.001; OR = 1.45, P = 0.032; OR = 3.42, P < 0.001; respectively). CONCLUSION: Our study indicates that CDH13 methylation may play an important role in the carcinogenesis, development and progression of bladder cancer. In addition, CDH13 methylation has the potential to be a useful biomarker for bladder cancer screening in urine samples and to be a prognostic biomarker in the clinic.


Assuntos
Biomarcadores Tumorais/metabolismo , Caderinas/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Caderinas/genética , Humanos , Metilação , Regiões Promotoras Genéticas
11.
Chin J Traumatol ; 18(5): 296-301, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26777715

RESUMO

The bony naso-orbital-ethmoid (NOE) complex is a 3-dimensional delicate anatomic structure. Damages to this region may result in severe facial dysfunction and malformation. The management and optimal surgical treatment strategies of NOE fractures remain controversial. For a patient with NOE trauma, doctors should perform comprehensive clinical examination and radiographic analysis to assess the type and extent of fracture. The results of assessment will assist doctors to make a patientspecific program for the sake of reducing post-operation complications and restoring normal appearance and function as much as possible. This review focuses on the advancement of management of NOE fractures including symptoms, classifications, diagnosis, approaches, treatment and new techniques in this field.


Assuntos
Osso Etmoide/lesões , Osso Nasal/lesões , Fraturas Orbitárias/cirurgia , Osso Etmoide/diagnóstico por imagem , Osso Etmoide/cirurgia , Fixação de Fratura , Humanos , Osso Nasal/diagnóstico por imagem , Osso Nasal/cirurgia , Fraturas Orbitárias/diagnóstico por imagem , Complicações Pós-Operatórias/prevenção & controle , Procedimentos de Cirurgia Plástica , Cirurgia Assistida por Computador , Tendões/cirurgia , Tomografia Computadorizada por Raios X
12.
Medicine (Baltimore) ; 103(21): e38268, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38788027

RESUMO

Renal cell carcinoma (RCC) stands among the top 10 malignant neoplasms with the highest fatality rates. It exhibits pronounced heterogeneity and robust metastatic behavior. Patients with RCC may present with solitary or multiple metastatic lesions at various anatomical sites, and their prognoses are contingent upon the site of metastasis. When deliberating the optimal therapeutic approach for a patient, thorough evaluation of significant risk factors such as the feasibility of complete resection, the presence of oligometastases, and the patient's functional and physical condition is imperative. Recognizing the nuanced differences in RCC metastasis to distinct organs proves advantageous in contemplating potential treatment modalities aimed at optimizing survival outcomes. Moreover, discerning the metastatic site holds promise for enhancing risk stratification in individuals with metastatic RCC. This review summarizes the recent data pertaining to the current status of different RCC metastatic sites and elucidates their role in informing clinical management strategies across diverse metastatic locales of RCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/secundário , Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Neoplasias Renais/terapia , Metástase Neoplásica , Prognóstico
13.
Front Plant Sci ; 14: 1096831, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37342142

RESUMO

Sclerotinia sclerotiorum, the causal agent of Sclerotinia stem rot (SSR) on more than 450 plant species, is a notorious fungal pathogen. Nitrate reductase (NR) is required for nitrate assimilation that mediates the reduction of nitrate to nitrite and is the major enzymatic source for NO production in fungi. To explore the possible effects of nitrate reductase SsNR on the development, stress response, and virulence of S. sclerotiorum, RNA interference (RNAi) of SsNR was performed. The results showed that SsNR-silenced mutants showed abnormity in mycelia growth, sclerotia formation, infection cushion formation, reduced virulence on rapeseed and soybean with decreased oxalic acid production. Furthermore SsNR-silenced mutants are more sensitive to abiotic stresses such as Congo Red, SDS, H2O2, and NaCl. Importantly, the expression levels of pathogenicity-related genes SsGgt1, SsSac1, and SsSmk3 are down-regulated in SsNR-silenced mutants, while SsCyp is up-regulated. In summary, phenotypic changes in the gene silenced mutants indicate that SsNR plays important roles in the mycelia growth, sclerotia development, stress response and fungal virulence of S. sclerotiorum.

14.
Fitoterapia ; 165: 105393, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36528150

RESUMO

Four novel iridoid glycosides neocornuside E-H (1-4), together with nine known ones (5-13), were isolated from fruits of Cornus officinalis. Their chemical structures were determined on the basis of spectroscopic analyses and comparing of the literature data. All of the isolated compounds were evaluated for their antidiabetic activity in insulin resistant HepG2 cells. Compounds 2, 4, 5, 8, and 12 exhibited antidiabetic activities with EC50 values of 40.12, 2.54, 70.43, 15.31, and 4.86 µM, respectively. Flow Sight cytometry analysis indicated that compounds 2, 4, 5, 8, and 12 improved the ability of 2-NBDG uptake of insulin-induced HepG2 cells.


Assuntos
Cornus , Glicosídeos Iridoides , Glicosídeos Iridoides/farmacologia , Glicosídeos Iridoides/química , Hipoglicemiantes/farmacologia , Cornus/química , Frutas/química , Estrutura Molecular , Insulina , Glicosídeos/química
15.
Int Immunopharmacol ; 123: 110736, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37549513

RESUMO

AIMS: Doxorubicin (DOX) is an effective anti-tumor drug, but the cardiotoxicity severely limits its clinical use. Interestingly, a hypothesis has emerged suggesting an association between DOX-induced cardiotoxicity and mitochondrial disorders and oxidative stress. The mitochonic acid 5 (MA5) shows promise in alleviating mitochondrial dysfunction by promoting mitochondrial ATP synthesis and reducing reactive oxygen species (ROS) accumulation, though its potential in ameliorating DOX-induced cardiotoxicity remains elusive. METHODS: Network pharmacology approach, molecular docking techniques, and molecular dynamics simulation (MDS) were used to reveal the specific drug targets and pharmaceutical mechanisms involved in the treatment of DOX-induced cardiotoxicity using MA5. For experimental verification, cardiomyocytes (H9c2) and mice were exposed to DOX in the presence or absence of MA5. Our investigation involved the assessment of echocardiographic parameters, cardiac enzymes, inflammatory factors, mitochondrial function, myocardial structure, and cardiomyocyte pyroptosis. RESULTS: Among the 100 core targets identified in network pharmacology, MA5 was pharmacologically active against DOX-induced cardiotoxicity via pathways implicated in cancer, prostate cancer, lipids and atherosclerosis. Molecular docking analysis confirmed that MA5 docked well with TNF-α, interleukin-6 (IL-6), and caspase-3. Furthermore, MA5 exhibited a stronger affinity toward TNF-α than IL-6 and caspase-3. Subsequent MDS revealed the stability of binding between MA5 and TNF-α. The DOX-challenged mice also displayed abnormal myocardial enzymogram, disrupted systolic and diastolic function, and elevated inflammation and cardiomyocyte pyroptosis, which could be mitigated by the administration of MA5. Similarly, H9c2 cells exposed to DOX showed increased intracellular ROS production and impaired mitochondrial function, which were relieved by MA5 treatment. CONCLUSION: Our findings suggest that MA5 attenuates DOX-induced cardiac anomalies through the TNF-α-mediated regulation of inflammation and pyroptosis. These insights offer a potential therapeutic strategy for managing DOX-induced cardiac complications, thereby improving the safety and efficacy of cancer treatments.


Assuntos
Miócitos Cardíacos , NF-kappa B , Masculino , Camundongos , Animais , NF-kappa B/metabolismo , Miócitos Cardíacos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Piroptose , Caspase 3/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Cardiotoxicidade/tratamento farmacológico , Cardiotoxicidade/metabolismo , Interleucina-6/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Simulação de Acoplamento Molecular , Doxorrubicina/efeitos adversos , Estresse Oxidativo , Inflamação/metabolismo , Apoptose
16.
Sci Total Environ ; 820: 153267, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35074368

RESUMO

Cyanobacterial blooms are increasingly threatening the aquatic ecosystem functioning as a result of the global warming and eutrophication. The "top-down" control of cyanobacteria from consumers like the protozoans shows great potential because of the effectiveness and environment-friendliness. To reveal how the nutrition availability and elevated temperature affect the cyanobacteria removal through protozoans grazing, we grew the toxic Microcystis aeruginosa and the mixotrophic Ochromonas gloeopara in monocultures and cocultures at environmentally relevant nitrogen levels (0.5-8.0 mg L-1) under 25 °C and 30 °C, respectively. The growth of M. aeruginosa in monocultures was significantly enhanced as nitrogen concentration and temperature rose, partially benefitting from the promoted photosynthesis. By contrast, nitrogen availability affected neither the photoautotrophic growth nor the feeding on Microcystis of the mixotrophic O. gloeopara, but high temperature induced the mixotroph to be more heterotrophic as evidenced by the suppressed photosynthesis but strengthened feeding activity. Accordingly, the M. aeruginosa removal through O. gloeopara grazing in cocultures was delayed with increasing nitrogen, which, however, was sharply accelerated by elevated temperature. Based on the Gaussian models fitting, the theoretical time that the Microcystis was removed at 25 °C was prolonged from about 7.5 days to 10 days with increased nitrogen, but it was reduced to less than 4.6 days in all groups at 30 °C. While the intensity of Microcystis blooms is strongly positively correlated to the nutrition availability and temperature, the present study provided references for the practical application of Microcystis removal through grazing outdoors.


Assuntos
Microcystis , Ochromonas , Ecossistema , Microcistinas , Nitrogênio , Temperatura
17.
Phytochemistry ; 202: 113314, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35810878

RESUMO

Epimesatines A-I, nine undescribed prenylated flavonoids, along with ten known analogues, were isolated from the aerial parts of Epimedium sagittatum Maxim. The structures and absolute configurations of epimesatines A-I were determined using a combination of spectroscopic data, Rh2(OCOCF3)4-induced electronic circular dichroism (ECD) experiments, ECD comparisons, and X-ray crystallography analysis. Epimesatines A and I displayed notable activities on the viabilities of human non-small cell lung cancer (NSCLC) A549 cells with IC50 values of 1.77 and 9.97 µM, respectively. Furthermore, epimesatines A and I significantly inhibited the expression of sphingosine kinase 1 (SPHK1) in A549 cells. In addition, none of these compounds showed obvious toxicity on normal human lung bronchial epithelial BEAS-2B cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Epimedium , Neoplasias Pulmonares , Epimedium/química , Epimedium/metabolismo , Flavonoides/química , Humanos , Fosfotransferases (Aceptor do Grupo Álcool)
18.
Phytochemistry ; 200: 113230, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35568259

RESUMO

Seven undescribed lignans, equiselignan A-F, and six undescribed terpenoids, equiseterpenoid A-E (including two pairs of enantiomers, (+/-)-equiselignan A and (+/-)-equiseterpenoid E), were isolated from the stems of Ephedra equisetina Bunge. Their structures were elucidated by spectroscopic methods, and the absolute configurations of the undescribed compounds were determined by interpretation of their electronic circular dichroic (ECD) and optical rotation data. In ß-hexosaminidase (ß-Hex) release assay, anti-asthmatic activities of all of the compounds were evaluated by releasing ß-Hex in C48/80-induced RBL-2H3 cells. The ß-Hex release rates of equiselignan B and equiseterpenoid B were 0.86 ± 0.094 and 0.86 ± 0.012 by comparing with model group, whereupon equiselignan B and equiseterpenoid B exhibited significant anti-asthmatic activities.


Assuntos
Antiasmáticos , Ephedra , Lignanas , Ephedra/química , Lignanas/química , Lignanas/farmacologia , Estrutura Molecular , Estereoisomerismo , Terpenos/farmacologia
19.
PLoS One ; 16(12): e0260977, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34882717

RESUMO

Ramp metering on freeway is one of the effective methods to alleviate traffic congestion. This paper advances the field of freeway ramp metering by introducing an application to the on-ramp, capitalizing on the macro traffic follow theory and improved the freeway traffic flow. The Particle Swarm Optimization (PSO) based on Proportional Integral Derivative (PID) controller is further developed to single ramp metering as well as to optimize the PID parameters. The approach is applied to a case study of the Changyi Freeway(G5513) in Hunan, China. The simulation is conducted by applying the actual profile traffic data to PID controller to adjust the entering traffic flow on the freeway on-ramp. The results show that the PSO-PID controller tends to converge in about 80 minutes, and the density tends to be stable after 240 iterations. The system has smaller oscillation, more accurate adjustment of ramp regulation rate, and more ideal expected traffic flow density. The traffic congestion on mainline is effectively slowed down, traffic efficiency is improved, and travel time and cost are reduced. The nonlinear processing ability of PSO-PID controller overcomes the defects of the traditional manual closing ramp, and can be successfully applied in the field of intelligent ramp metering.


Assuntos
Acidentes de Trânsito/prevenção & controle , Algoritmos , Condução de Veículo/estatística & dados numéricos , Simulação por Computador , Humanos , Segurança
20.
Chemosphere ; 272: 129645, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33465615

RESUMO

The solar ultraviolet-B radiation (UVB) is increasingly affecting the aquatic ecosystems due to the long-term antropic damage to the stratospheric ozone. The distrupted interspecies competition is one of the primary causes driving the plankton community composition shifts under UVB stress. To reveal the competitive responses to enhanced UVB radiation, we grew two green algae Scenedesmus obliquus and Chlorella pyrenoidosa, and the unicellular cyanobacterium Microcystis aeruginosa in monocultures and in cocultures under differerent UVB intensities (0, 0.3 and 0.7 W m-2), respectively. Results showed that elevated UVB radiation consistently decreased the population carrying capacies and the photosynthesis of the three species in monocultures. While cocultivated, C. pyrenoidosa was competively excluded by the presence of S. obliquus, and the competitive outcome was not affected by UVB exposure. By contrast, unicellular M. aeruginosa overwhelmingly suppressed the population growth of S. obliquus under no UVB, yet S. obliquus tended to be a better competitor under 0.3-0.7 W m-2 UVB exposure. The species-specific photosynthesis sensitivity to UVB can partly explain the different tolerance of the algae to UVB and the change of competition outcome under elevated UVB. The present study elucidated the potential role of increased UVB radiation in determining the competitions between phytoplankton species, contributing to the understanding of phytoplankton community shifts under enhanced UVB stress.


Assuntos
Chlorella , Microcystis , Ecossistema , Fotossíntese , Dinâmica Populacional
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