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1.
Int Microbiol ; 27(2): 535-544, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37505307

RESUMO

Cajaninstilbene acid (CSA), longistylin A (LLA), and longistylin C (LLC) are three characteristic stilbenes isolated from pigeon pea. The objective of this study was to evaluate the antibacterial activity of these stilbenes against Staphylococcus aureus and even methicillin-resistant Staphylococcus aureus (MRSA) and test the possibility of inhibiting biofilm formation. The minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of these stilbenes were evaluated. And the results showed that LLA was most effective against tested strains with MIC and MBC values of 1.56 µg/mL followed by LLC with MIC and MBC values of 3.12 µg/mL and 6.25 µg/mL as well as CSA with MIC and MBC values of 6.25 µg/mL and 6.25-12.5 µg/mL. Through growth curve and cytotoxicity analysis, the concentrations of these stilbenes were determined to be set at their respective 1/4 MIC in the follow-up research. In an anti-biofilm formation assay, these stilbenes were found to be effectively inhibited bacterial proliferation, biofilm formation, and key gene expressions related to the adhesion and virulence of MRSA. It is the first time that the anti-S. aureus and MRSA activities of the three stilbenes have been systematically reported. Conclusively, these findings provide insight into the anti-MRSA mechanism of stilbenes from pigeon pea, indicating these compounds may be used as antimicrobial agents or additives for food with health functions, and contribute to the development as well as application of pigeon pea in food science.


Assuntos
Cajanus , Staphylococcus aureus Resistente à Meticilina , Estilbenos , Antibacterianos/farmacologia , Estilbenos/farmacologia , Testes de Sensibilidade Microbiana , Anticorpos/farmacologia , Biofilmes
2.
Geriatr Nurs ; 46: 178-183, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35728300

RESUMO

Based on the theory of planned behavior, the aim of this study was to describe the influencing factors of patient delay intentions and behaviors in benign prostatic hyperplasia (BPH) patients and to provide a reference for the development of a patient delay intention scale. This study was carried out over 4 months in 2021 in Daqing, Heilongjiang, China. The participants were 20 patients with BPH who were aged 60 to 82 years and experienced patient delay; participants were selected through a purposive sampling method. The data were collected via face-to-face semistructured interviews. Five main themes emerged from the interviews, including an insufficient understanding of symptoms, experiences of coping instead of seeking health care, negative attitudes toward care-seeking, the influence of others on decision-making for care-seeking, and obstacles to seeking health care. In conclusion, the patient delay intentions and behaviors of BPH patients are the result of a combination of many factors.


Assuntos
Hiperplasia Prostática , Idoso , China , Humanos , Masculino , Aceitação pelo Paciente de Cuidados de Saúde , Hiperplasia Prostática/complicações , Hiperplasia Prostática/terapia , Pesquisa Qualitativa
3.
Anal Chem ; 93(35): 11920-11928, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34405989

RESUMO

To our knowledge, this was the first study in which caffeic acid (CA) was successfully evaluated as a matrix to enhance the in situ detection and imaging of endogenous proteins in three biological tissue sections (i.e., a rat brain and Capparis masaikai and germinating soybean seeds) by matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI). Our results show several properties of CA, including strong ultraviolet absorption, a super-wide MS detection mass range close to 200,000 Da, micrometer-sized matrix crystals, uniform matrix deposition, and high ionization efficiency. More high-molecular-weight (HMW) protein ion signals (m/z > 30,000) could be clearly detected in biological tissues with the use of CA, compared to two commonly used MALDI matrices, i.e., sinapinic acid (SA) and ferulic acid (FA). Notably, CA shows excellent performance for HMW protein in situ detection from biological tissues in the mass range m/z > 80,000, compared to the use of SA and FA. Furthermore, the use of a CA matrix also significantly enhanced the imaging of proteins on the surface of selected biological tissue sections. Three HMW protein ion signals (m/z 50,419, m/z 65,874, and m/z 191,872) from a rat brain, two sweet proteins (mabinlin-2 and mabinlin-4) from a Capparis masaikai seed, and three HMW protein ion signals (m/z 94,838, m/z 134,204, and m/z 198,738) from a germinating soybean seed were successfully imaged for the first time. Our study proves that CA has the potential to become a standard organic acid matrix for enhanced tissue imaging of HMW proteins by MALDI-MSI in both animal and plant tissues.


Assuntos
Lasers , Proteínas , Animais , Ácidos Cafeicos , Peso Molecular , Ratos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
4.
FASEB J ; 34(5): 6871-6887, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32248623

RESUMO

This study used constitutive CD226 gene knockout (KO) mice as a model to investigate the functions and mechanisms of CD226 in megakaryocyte (MK) maturation and platelet activation. Although CD226 deficiency did not cause MK polyploidization or platelet granule abnormalities, increased MK counts were detected in the femora bone marrow (BM) and spleen of CD226 KO mice. Particularly, CD226 KO mice have a more extensive membrane system in MKs and platelets than wild-type (WT) mice. We also demonstrated that CD226 KO mice displayed increased platelet counts, shortened bleeding time, and enhanced platelet aggregation. CD226 KO platelets had an increased mature platelet ratio compared to the control platelets. In addition, the observed reduction in bleeding time may be due to decreased nitric oxide (NO) production in the platelets. Platelet-specific CD226-deficient mice showed similar increased MK counts, shortened bleeding time, enhanced platelet aggregation, and decreased NO production in platelets. Furthermore, we performed middle cerebral artery occlusion-reperfusion surgery on WT and CD226 KO mice to explore the potential effect of CD226 on acute ischemia-reperfusion injury; the results revealed that CD226 deficiency led to significantly increased infarct area. Thus, CD226 is a promising candidate for the treatment of thrombotic disorders.


Assuntos
Antígenos de Diferenciação de Linfócitos T/sangue , Megacariócitos/citologia , Megacariócitos/fisiologia , Ativação Plaquetária/fisiologia , Animais , Antígenos de Diferenciação de Linfócitos T/genética , Plaquetas/fisiologia , Plaquetas/ultraestrutura , Isquemia Encefálica/sangue , Isquemia Encefálica/genética , Isquemia Encefálica/patologia , Modelos Animais de Doenças , Feminino , Integrina beta3/sangue , Masculino , Megacariócitos/ultraestrutura , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Ativação Plaquetária/genética , Adesividade Plaquetária/genética , Adesividade Plaquetária/fisiologia , Agregação Plaquetária/genética , Agregação Plaquetária/fisiologia , Contagem de Plaquetas , Trombopoese/genética , Trombopoese/fisiologia
5.
World J Surg Oncol ; 18(1): 136, 2020 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-32563267

RESUMO

BACKGROUND: Leukocyte-associated immunoglobulin-like receptor-1 (LAIR-1) is a collagen receptor belonging to the immunoglobulin superfamily. Although previous studies have evaluated the biological role of LAIR in solid tumors, the precise mechanisms underlying the functions of LAIR-1 as a regulator of tumor biological functions remain unclear. METHODS: LAIR-1 expression was evaluated by immunohistochemical analysis using an osteosarcoma (OS) tissue microarray. Wound healing and transwell migration assays were performed to evaluate tumor cell migration. Quantitative real-time polymerase chain reaction (qPCR) and western blotting were conducted to detect the expression of epithelial-mesenchymal transition (EMT)-related molecules. RNA-sequencing (RNA-seq) was conducted to evaluate the mRNA expression profiles after overexpressing LAIR-1 in OS cells. Glucose transporter (Glut)1 expression in OS cells was evaluated by western blotting. RESULTS: LAIR-1 expression was significantly different between the T1 and T2 stages of OS tumors, and it inhibited OS cell migration. LAIR-1 expression was inversely correlated with the expression of Twist1, an EMT-associated transcription factor, via the Forkhead box O1 signal transduction pathway. Furthermore, RNA-seq and qPCR demonstrated that the expression of EMT energy metabolism-related molecules was significantly reduced after LAIR-1 overexpression. CONCLUSIONS: LAIR-1 overexpression decreased the expression of Glut1 and inhibited the expression of EMT-related molecules in OS cells. These findings provide new insights into the molecular mechanism underlying OS progression.


Assuntos
Neoplasias Ósseas/patologia , Metabolismo Energético , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Transportador de Glucose Tipo 1/metabolismo , Osteossarcoma/patologia , Receptores Imunológicos/metabolismo , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Humanos , Masculino , Osteossarcoma/genética , Osteossarcoma/metabolismo , Prognóstico , Receptores Imunológicos/genética , Transdução de Sinais , Taxa de Sobrevida , Adulto Jovem
6.
Regul Toxicol Pharmacol ; 88: 283-290, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28697995

RESUMO

The aim of the study was to evaluate the safety of flavonoid fraction of Lithocarpus polystachyus Rehd (Sweet Tea-F, ST-F) in mice and rats through acute and sub-chronic toxicity studies respectively. For acute toxicity study, a single dose of 5000 mg/kg of ST-F was given orally to healthy KM mice. The mice were observed mortality and toxic symptoms for 24 h, then once a day up to 14 days. In the sub-chronic toxicity study, ST-F was administered orally at doses of 0, 70, 140, 560 mg/kg/day to rats for 26 weeks. Body weight and food intake were recorded weekly. Hematological, biochemical, coagulation and organ parameters were analyzed at the end of 26 weeks administration. Vital organs were evaluated by histopathology. In the acute toxicity study, ST-F caused neither significant toxic symptoms, nor mortality in mice. In sub-chronic toxicity study, daily oral administration of ST-F at the dose of 70 mg/kg resulted in a significant increase (P < 0.05) in the relative body weight at the 10-week, and the same situation brought at the dose of 140 mg/kg/day at the 22-week. Hematological and biochemical showed significant changes (P < 0.01 or P < 0.05) in WBC, GLU, ALP, AST and serum electrolytes levels at the dose of 560 mg/kg/day. The amount of RBC decreased significantly (P < 0.05) while the content of PLT slightly increased (P < 0.05) at the dose of 140 mg/kg/day. In additional, no obvious histological changes were observed in vital organs of ST-F treated animals compared to control group. The ST-F may be exit slight side effects at the dose of 560 mg/kg/day in rats. Thus, the overall results show that the no-observed adverse effect level (NOAEL) of ST-F was considered to be 140 mg/kg for male SD rats.


Assuntos
Fagaceae/química , Flavonoides/toxicidade , Extratos Vegetais/toxicidade , Administração Oral , Animais , Camundongos , Nível de Efeito Adverso não Observado , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade Aguda , Testes de Toxicidade Subcrônica
7.
Zhonghua Gan Zang Bing Za Zhi ; 23(3): 175-9, 2015 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-25938828

RESUMO

OBJECTIVE: To assess the relationship between nodular goiter and hepatitis C virus infection. METHODS: Ninety-seven cases of early treatment in patients with chronic hepatitis C were collected for analysis.Data on patient age,sex,hepatitis duration and other general information were collected.In addition, data on clinical measures of thyroid function (including T3, t4, tSH) and thyroid autoantibodies (thyroid peroxidase antibody TPO-Ab, thyroglobulin antibody Tg-Ab), as well as findings from thyroid dimensional ultrasonography were collected. One hundred and eleven cases of early treatment in patients with chronic hepatitis B and 106 eases of females 40 years old or older with high risk of nodular goiter were collected for use as controls.The relationship between nodular goiter with thyroid function, thyroid autoantibodies levels,sex,age,and hepatitis C virus infection were statistically analyzed. RESULTS: The prevalence rates of nodular goiter in the chronic hepatitis C group, the chronic hepatitis B group and the more than or equal to 40 year-old women with high risk of nodular goiter were 53.6%,36.9% and 59.4% respectively.The prevalence rates of nodular goiter in the chronic hepatitis C group and the more than or equal to 40 year-old women with high risk of nodular goiter were significantly higber than that in the chronic hepatitis B group (x² values: 5.820 and 10.996, P < 0.05). The average age of patients with chronic hepatitis C combined with nodular goiter was significantly higher than their counterparts without goiter (F=6.408, P < 0.05),and the prevalence rate in the more than or equal to 40 year-old women with high risk of nodular goiter was significantly higher than that of their counterparts who were less than 40 years-old (60.0% vs. 23.5%; x² =7.499, P less than 0.05). The prevalence of nodular goiter in patients with chronic hepatitis C was significantly greater for females than for males (62.1% vs. 41.0%; x 2 =4.152, P < 0.05).The prevalence of nodular goiter in patients with chronic hepatitis C was also significantly higher for females more than or equal to 40 years old than for males (70.2%, 33/47 vs. 45.5%,15/33; x² = 4.952, P < 0.05).The duration of hepatitis, thyroid function and thyroid autoantibodies were similar between the patients in the chronic hepatitis C group with or without nodular goiter. CONCLUSIONS: The patients with chronic hepatitis C had a higher prevalence of nodular goiter,with an average of up to 53.6%, than the patients with chronic hepatitis B,and the women the more than or equal to 40 years old had even higher prevalence, at 70.2%, suggesting that patients with chronic hepatitis C should be routinely examined by thyroid ultrasound. Thyroid function and thyroid autoantibodies were not correlated with prevalence of goiter among the chronic hepatitis C patients.


Assuntos
Bócio Nodular , Hepatite C Crônica , Autoanticorpos , Feminino , Hepatite B Crônica , Humanos , Masculino , Prevalência
8.
Patient Prefer Adherence ; 18: 657-666, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38500561

RESUMO

Purpose: To test a hypothetical pathway model to estimate the links between health literacy, social support, illness perception, and disease management self-efficacy. Methods: This cross-sectional study, conducted from June to October 2022, involved the recruitment of 210 patients with chronic diseases at two primary care facilities. Participants completed the Health Literacy Management Scale, Self-Efficacy for Managing Chronic Disease 6-Item Scale, Social Support Rating Scale and Brief Illness Perception Questionnaire. We used the PROCESS macro for R to determine the hypothetical pathway model. Results: The direct effect of health literacy on self-efficacy was significant (ß=0.1792, 95% CI: 0.0940-0.2644), and social support played a partial mediating role between health literacy and self-efficacy (ES=0.0761, 95% CI: 0.0398-0.1204). Illness perception moderated the relationship between social support and self-efficacy (ß=-0.0153, 95% CI: -0.0268- -0.0039). Conclusion: Proposed a conceptual model including the mediating effect of social support and the moderating effect of illness perception, which helps to clarify the underlying mechanisms between health literacy and self-efficacy.

9.
J Clin Invest ; 134(5)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38194275

RESUMO

Neutrophil extracellular traps (NETs), a web-like structure of cytosolic and granule proteins assembled on decondensed chromatin, kill pathogens and cause tissue damage in diseases. Whether NETs can kill cancer cells is unexplored. Here, we report that a combination of glutaminase inhibitor CB-839 and 5-FU inhibited the growth of PIK3CA-mutant colorectal cancers (CRCs) in xenograft, syngeneic, and genetically engineered mouse models in part through NETs. Disruption of NETs by either DNase I treatment or depletion of neutrophils in CRCs attenuated the efficacy of the drug combination. Moreover, NETs were present in tumor biopsies from patients treated with the drug combination in a phase II clinical trial. Increased NET levels in tumors were associated with longer progression-free survival. Mechanistically, the drug combination induced the expression of IL-8 preferentially in PIK3CA-mutant CRCs to attract neutrophils into the tumors. Further, the drug combination increased the levels of ROS in neutrophils, thereby inducing NETs. Cathepsin G (CTSG), a serine protease localized in NETs, entered CRC cells through the RAGE cell surface protein. The internalized CTSG cleaved 14-3-3 proteins, released BAX, and triggered apoptosis in CRC cells. Thus, our studies illuminate a previously unrecognized mechanism by which chemotherapy-induced NETs kill cancer cells.


Assuntos
Neoplasias Colorretais , Armadilhas Extracelulares , Humanos , Animais , Camundongos , Modelos Animais de Doenças , Classe I de Fosfatidilinositol 3-Quinases , Combinação de Medicamentos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética
10.
Int Immunopharmacol ; 124(Pt A): 110838, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37633235

RESUMO

Colorectal cancer (CRC) is a growing concern due to its high morbidity and mortality, and the search for effective and less toxic active substances against inflammatory bowel diseases has been a hot topic in the research and development of drugs against CRC. It is reported that monotropein isolated from the roots of Morinda officinalis, can improve Dextran Sodium Sulfate (DSS)-induced ulcerative colitis in mice, but its therapeutic effects and mechanisms for CRC treatment are still to be investigated. In the present study, we first used molecular docking, BLI, CESTA, and DARTS methods to detest whether monotropein targets VDR proteins. In addition, we used tumor cell conditioned co-culture and four models of macrophage polarisation to investigate the regulation of four macrophage polarisations by monotropein using RT-PCR, IF and western blot. Furthermore, we further validated the target of action of monotropein for the treatment of Azoxymethane (AOM)/DSS induced colitis associated cancer (CAC) using knockout animals. Meanwhile, we further explored the mechanism of action of monotropein in regulating polarisation by detecting JAK/STAT1-related genes and proteins. Molecular docking and biofilm interference techniques showed that monotropein bound to the VDR, and additional results from CESTA and DARTS suggested that VDR proteins are targets of monotropein. Furthermore, in tumor cell conditioned co-cultures or LPS + IFN-γ induced RAW264.7 cells, VDR translocation to the nucleus was reduced, JAK1/STAT1 signaling pathway proteins were up-regulated, and macrophages were polarised towards the M1-type after monotropein intervention. Animal models in which normal VDR or myeloid VDR was knocked out confirmed that JAK1 levels in intestinal tissues were increased after monotropein intervention, macrophages were polarised towards the M1 type, and CAC paracarcinomas were ameliorated. Taken together, the present study concluded that monotropein inhibited colitis-associated cancers through macrophage polarisation regulated by VDR/JAK1/STAT1.

11.
Chem Commun (Camb) ; 59(26): 3842-3845, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36883606

RESUMO

In this study, polyacrylamide gel (PAAG) was successfully used as a new embedding medium to provide the more effective maintenance of biological tissues during the sectioning process, enhancing the tissue imaging of metabolites via matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI). Herein, PAAG, agarose, gelatin, optimal cutting temperature compound (OCT), and ice media were used to embed rat liver and Atlantic salmon (Salmo salar) eyeball samples. These embedded tissues were then sectioned into thin slices and thaw-mounted on conductive microscope glass slides for MALDI-MSI detection to evaluate the embedding effects. The results showed that PAAG embedding has characteristics superior to those of commonly-used embedding media (e.g., agarose, gelatin, OCT, and ice) with the advantages of one-step operation without heating, a better performance of morphology maintenance, the absence of PAAG polymer-ion-related interference below m/z 2000, and the more efficient in situ ionization of metabolites, providing a significant enhancement of both the numbers and intensities of the metabolite ion signals. Our study demonstrates the potential of PAAG embedding as a standard practice for metabolite MALDI tissue imaging, which will lead to an expanded application scope of MALDI-MSI.


Assuntos
Gelatina , alfa 2-Macroglobulinas Associadas à Gravidez , Ratos , Animais , Gravidez , Feminino , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Gelo , Sefarose
12.
Fitoterapia ; 169: 105548, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37236512

RESUMO

The extract of the whole plant of Carpesium abrotanoides L. yielded five new sesquiterpenes including four eudesmanes (1-4) and one eremophilane (5). The new compounds were characterized by spectroscopic analysis especially 1D and 2D NMR spectroscopy and HRESIMS data. Structurally, both compounds 1 and 2 were sesquiterpene epoxides and 2 owned an epoxy group at C-4/C-15 position to form a spiro skeleton. Compounds 4 and 5 were two sesquiterpenes without lactones and 5 possessed a carboxy group in the molecule. Additionally, all the isolated compounds were preliminarily evaluated for the inhibitory activity against SARS-CoV-2 main protease. As a result, compound 2 showed moderate activity with an IC50 value of 18.79 µM, while other compounds were devoid of noticeable activity (IC50 > 50 µM).


Assuntos
Asteraceae , COVID-19 , Sesquiterpenos de Eudesmano , Sesquiterpenos , Estrutura Molecular , Sesquiterpenos Policíclicos , SARS-CoV-2 , Sesquiterpenos de Eudesmano/farmacologia , Espectroscopia de Ressonância Magnética , Asteraceae/química
13.
Zhong Yao Cai ; 35(3): 371-5, 2012 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-22876673

RESUMO

OBJECTIVE: To build a new processing procedure for Croton tiglium, providing a more simple, efficient and safe way of processing. METHODS: Used the contents of isoguanosine and toxic protein in Croton tiglium as the indexes to investigate the effect of different temperature, thickness and baked time on processing for Croton tiglium. After established all factors and levels, processed a batch of Croton tiglium under optimum processing conditions and compared it with raw Croton tiglium in the test of acute toxicity and gastrointestinal propulsive motility. RESULTS: The parameters of optimum processing were as follows:the temperature was set at 180 degrees C, the thickness of placement was 3 cm and baked time was 90 min. The LD50 value of raw Croton tiglium and the processed Croton tiglium was 888 mg/kg and 2139 mg/kg respectively. CONCLUSION: The processing procedure is simple, affordable, safe and efficient, deserved to promote for application.


Assuntos
Croton , Motilidade Gastrointestinal/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Sementes/química , Tecnologia Farmacêutica/métodos , Adenosina , Animais , Croton/química , Feminino , Guanosina/análise , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos , Extratos Vegetais/química , Proteínas de Plantas/análise , Sementes/toxicidade
14.
Cancers (Basel) ; 14(17)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36077618

RESUMO

Multiple myeloma (MM) is a complex hematologic malignancy characterized by the uncontrolled proliferation of clonal plasma cells in the bone marrow that secrete large amounts of immunoglobulins and other non-functional proteins. Despite decades of progress and several landmark therapeutic advancements, MM remains incurable in most cases. Standard of care frontline therapies have limited durable efficacy, with the majority of patients eventually relapsing, either early or later. Induced drug resistance via up-modulations of signaling cascades that circumvent the effect of drugs and the emergence of genetically heterogeneous sub-clones are the major causes of the relapsed-refractory state of MM. Cytopenias from cumulative treatment toxicity and disease refractoriness limit therapeutic options, hence creating an urgent need for innovative approaches effective against highly heterogeneous myeloma cell populations. Here, we present a comprehensive overview of the current and future treatment paradigm of MM, and highlight the gaps in therapeutic translations of recent advances in targeted therapy and immunotherapy. We also discuss the therapeutic potential of emerging preclinical research in multiple myeloma.

15.
Chem Commun (Camb) ; 58(5): 633-636, 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-34897326

RESUMO

Michler's ethylketone (MEK, 4,4'-bis(diethylamino)benzophenone), commonly-known as an intermediate in the synthesis of dyes and pigments, was successfully screened and optimized as a novel matrix for the enhancement of lipid in situ detection and imaging in tissues by MALDI-MSI. The results show several properties of MEK as a powerful MALDI matrix, including strong UV absorption, µm-sized crystals and uniform matrix-coating, super high vacuum chemical stability, low matrix-related ion interference, super soft ionization, and high lipid ionization efficiency.


Assuntos
Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
16.
Nat Commun ; 13(1): 1038, 2022 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-35210415

RESUMO

Although recent work has described the microbiome in solid tumors, microbial content in hematological malignancies is not well-characterized. Here we analyze existing deep DNA sequence data from the blood and bone marrow of 1870 patients with myeloid malignancies, along with healthy controls, for bacterial, fungal, and viral content. After strict quality filtering, we find evidence for dysbiosis in disease cases, and distinct microbial signatures among disease subtypes. We also find that microbial content is associated with host gene mutations and with myeloblast cell percentages. In patients with low-risk myelodysplastic syndrome, we provide evidence that Epstein-Barr virus status refines risk stratification into more precise categories than the current standard. Motivated by these observations, we construct machine-learning classifiers that can discriminate among disease subtypes based solely on bacterial content. Our study highlights the association between the circulating microbiome and patient outcome, and its relationship with disease subtype.


Assuntos
Infecções por Vírus Epstein-Barr , Microbiota , Transtornos Mieloproliferativos , Bactérias/genética , Disbiose/microbiologia , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4/genética , Humanos , Microbiota/genética
17.
J Clin Invest ; 132(4)2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35085104

RESUMO

Eltrombopag, an FDA-approved non-peptidyl thrombopoietin receptor agonist, is clinically used for the treatment of aplastic anemia, a disease characterized by hematopoietic stem cell failure and pancytopenia, to improve platelet counts and stem cell function. Eltrombopag treatment results in a durable trilineage hematopoietic expansion in patients. Some of the eltrombopag hematopoietic activity has been attributed to its off-target effects, including iron chelation properties. However, the mechanism of action for its full spectrum of clinical effects is still poorly understood. Here, we report that eltrombopag bound to the TET2 catalytic domain and inhibited its dioxygenase activity, which was independent of its role as an iron chelator. The DNA demethylating enzyme TET2, essential for hematopoietic stem cell differentiation and lineage commitment, is frequently mutated in myeloid malignancies. Eltrombopag treatment expanded TET2-proficient normal hematopoietic stem and progenitor cells, in part because of its ability to mimic loss of TET2 with simultaneous thrombopoietin receptor activation. On the contrary, TET inhibition in TET2 mutant malignant myeloid cells prevented neoplastic clonal evolution in vitro and in vivo. This mechanism of action may offer a restorative therapeutic index and provide a scientific rationale to treat selected patients with TET2 mutant-associated or TET deficiency-associated myeloid malignancies.


Assuntos
Anemia Aplástica , Benzoatos/farmacologia , Proliferação de Células , Proteínas de Ligação a DNA , Dioxigenases , Células-Tronco Hematopoéticas/enzimologia , Hidrazinas/farmacologia , Pirazóis/farmacologia , Anemia Aplástica/tratamento farmacológico , Anemia Aplástica/genética , Anemia Aplástica/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Dioxigenases/antagonistas & inibidores , Dioxigenases/genética , Dioxigenases/metabolismo , Humanos , Camundongos , Camundongos Knockout
18.
Front Oncol ; 11: 601982, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33816232

RESUMO

BACKGROUND: Osteosarcoma (OS) is a highly malignant and aggressive bone tumor. This study was performed to explore the mechanisms of HuR (human antigen R) in the progression of OS. METHODS: HuR expression levels in OS tissues and cells were detected by immunohistochemistry and western blotting. HuR siRNA was transfected into SJSA-1 OS cells to downregulate HuR expression, and then cell proliferation, migration, and epithelial-mesenchymal transition (EMT) were evaluated. RNA immunoprecipitation was performed to determine the association of the long non-coding RNA (lncRNA) XIST and argonaute RISC catalytic component (AGO) 2 with HuR. Fluorescence in situ hybridization analysis was performed to detect the expression of lncRNA XIST. Western blotting and immunofluorescence assays were performed to observe AGO2 expression after HuR or/and lncRNA XIST knockdown. RESULTS: Knockdown of HuR repressed OS cell migration and EMT. AGO2 was identified as a target of HuR and silencing of HuR decreased AGO2 expression. The lncRNA XIST was associated with HuR-mediated AGO2 suppression. Moreover, knockdown of AGO2 significantly inhibited cell proliferation, migration, and EMT in OS. CONCLUSION: Our findings indicate that HuR knockdown suppresses OS cell EMT by regulating lncRNA XIST/AGO2 signaling.

19.
Int J Biol Macromol ; 180: 633-642, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33744251

RESUMO

The purpose of this paper was to explore the therapeutic effect and underlying mechanism of Tremella fuciformis polysaccharides (TFP) on ulcerative colitis (UC) based on dextran sodium sulfate (DSS)-induced mice UC model and lipopolysaccharide (LPS)-stimulated Caco-2 cells model. The results firstly indicated that TFP can significantly alleviate the symptoms and signs of the DSS-induced mice UC model, which manifests as improvement of body weight loss, increase of colon length, decrease of colon thickness and reduction of intestinal permeability. Then, results from histopathological and electron microscope analysis further implied that TFP could dramatically reduce inflammatory cells infiltration and restore intestinal epithelial barrier integrity. In addition, the experiments of LPS-stimulated Caco-2 cells model in vitro also further confirmed that TFP could markedly inhibit the expressions of pro-inflammatory cytokines and increase related genes or proteins expressions of intestinal barrier and mucus barrier. Taken together, these data suggested that TFP has a significant therapeutic effect on DSS-induced UC model, and its mechanisms are closely linked to the inhibition of inflammation and the restoration of intestinal barrier and mucus barrier function. These beneficial effects may make TFP a promising drug to be used in alleviating UC.


Assuntos
Basidiomycota/química , Colite Ulcerativa/prevenção & controle , Inflamação/prevenção & controle , Mucosa Intestinal/efeitos dos fármacos , Polissacarídeos/farmacologia , Animais , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Colite Ulcerativa/induzido quimicamente , Colo/efeitos dos fármacos , Colo/patologia , Colo/ultraestrutura , Sulfato de Dextrana , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Mucosa Intestinal/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Polissacarídeos/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
Cell Death Dis ; 12(2): 209, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33627622

RESUMO

Increased reactive oxygen species levels in the mitochondrial matrix can induce Parkin-dependent mitophagy, which selectively degrades dysfunctional mitochondria via the autolysosome pathway. Phosphorylated mitofusin-2 (MFN2), a receptor of parkin RBR E3 ubiquitin-protein ligase (Parkin), interacts with Parkin to promote the ubiquitination of mitochondrial proteins; meanwhile, the mitophagy receptors Optineurin (OPTN) and nuclear dot protein 52 (NDP52) are recruited to damaged mitochondria to promote mitophagy. However, previous studies have not investigated changes in the levels of OPTN, MFN2, and NDP52 during Parkin-mediated mitophagy. Here, we show that mild and sustained hydrogen peroxide (H2O2) stimulation induces Parkin-dependent mitophagy accompanied by downregulation of the mitophagy-associated proteins OPTN, NDP52, and MFN2. We further demonstrate that H2O2 promotes the expression of the miR-106b-93-25 cluster and that miR-106b and miR-93 synergistically inhibit the translation of OPTN, NDP52, and MFN2 by targeting their 3' untranslated regions. We further reveal that compromised phosphorylation of MYC proto-oncogene protein (c-Myc) at threonine 58 (T58) (producing an unstable form of c-Myc) caused by reduced nuclear glycogen synthase kinase-3 beta (GSK3ß) levels contributes to the promotion of miR-106b-93-25 cluster expression upon H2O2 induction. Furthermore, miR-106b-mediated and miR-93-mediated inhibition of mitophagy-associated proteins (OPTN, MFN2, and NDP52) restrains cell death by controlling excessive mitophagy. Our data suggest that microRNAs (miRNAs) targeting mitophagy-associated proteins maintain cell survival, which is a novel mechanism of mitophagy control. Thus, our findings provide mechanistic insight into how miRNA-mediated regulation alters the biological process of mitophagy.


Assuntos
MicroRNAs/metabolismo , Mitocôndrias/metabolismo , Mitofagia , Estresse Oxidativo , Regiões 3' não Traduzidas , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Regulação da Expressão Gênica , Glicogênio Sintase Quinase 3 beta/metabolismo , Células HEK293 , Células HeLa , Humanos , Peróxido de Hidrogênio/toxicidade , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , MicroRNAs/genética , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/genética , Mitocôndrias/patologia , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Mitofagia/efeitos dos fármacos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosforilação , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
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