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1.
Small ; 20(17): e2307728, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38263806

RESUMO

Herein, the structure of integrated M3D inverters are successfully demonstrated where a chemical vapor deposition (CVD) synthesized monolayer WSe2 p-type nanosheet FET is vertically integrated on top of CVD synthesized monolayer MoS2 n-type film FET arrays (2.5 × 2.5 cm) by semiconductor industry techniques, such as transfer, e-beam evaporation (EBV), and plasma etching processes. A low temperature (below 250 °C) is employed to protect the WSe2 and MoS2 channel materials from thermal decomposition during the whole fabrication process. The MoS2 NMOS and WSe2 PMOS device fabricated show an on/off current ratio exceeding 106 and the integrated M3D inverters indicate an average voltage gain of ≈9 at VDD = 2 V. In addition, the integrated M3D inverter demonstrates an ultra-low power consumption of 0.112 nW at a VDD of 1 V. Statistical analysis of the fabricated inverters devices shows their high reliability, rendering them suitable for large-area applications. The successful demonstration of M3D inverters based on large-scale 2D monolayer TMDs indicate their high potential for advancing the application of 2D TMDs in future integrated circuits.

2.
Appl Microbiol Biotechnol ; 108(1): 170, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38265689

RESUMO

The deep-sea environment is an extremely difficult habitat for microorganisms to survive in due to its intense hydrostatic pressure. However, the mechanisms by which these organisms adapt to such extreme conditions remain poorly understood. In this study, we investigated the metabolic adaptations of Microbacterium sediminis YLB-01, a cold and stress-tolerant microorganism isolated from deep-sea sediments, in response to high-pressure conditions. YLB-01 cells were cultured at normal atmospheric pressure and 28 ℃ until they reached the stationary growth phase. Subsequently, the cells were exposed to either normal pressure or high pressure (30 MPa) at 4 ℃ for 7 days. Using NMR-based metabolomic and proteomic analyses of YLB-01 cells exposed to high-pressure conditions, we observed significant metabolic changes in several metabolic pathways, including amino acid, carbohydrate, and lipid metabolism. In particular, the high-pressure treatment stimulates cell division and triggers the accumulation of UDP-glucose, a critical factor in cell wall formation. This finding highlights the adaptive strategies used by YLB-01 cells to survive in the challenging high-pressure environments of the deep sea. Specifically, we discovered that YLB-01 cells regulate amino acid metabolism, promote carbohydrate metabolism, enhance cell wall synthesis, and improve cell membrane fluidity in response to high pressure. These adaptive mechanisms play essential roles in supporting the survival and growth of YLB-01 in high-pressure conditions. Our study offers valuable insights into the molecular mechanisms underlying the metabolic adaptation of deep-sea microorganisms to high-pressure environments. KEY POINTS: • NMR-based metabolomic and proteomic analyses were conducted on Microbacterium sediminis YLB-01 to investigate the significant alterations in several metabolic pathways in response to high-pressure treatment. • YLB-01 cells used adaptive strategies (such as regulated amino acid metabolism, promoted carbohydrate metabolism, enhanced cell wall synthesis, and improved cell membrane fluidity) to survive in the challenging high-pressure environment of the deep sea. • High-pressure treatment stimulated cell division and triggered the accumulation of UDP-glucose, a critical factor in cell wall formation, in Microbacterium sediminis YLB-01 cells.


Assuntos
Actinomycetales , Proteômica , Aminoácidos , Glucose , Difosfato de Uridina , Microbacterium
3.
Acta Obstet Gynecol Scand ; 103(4): 740-750, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37710408

RESUMO

INTRODUCTION: This study aimed to investigate the imaging features, clinical characteristics and neonatal outcomes of pregnancy luteoma. MATERIAL AND METHODS: We retrospectively analyzed patients with pregnancy luteoma admitted to the First Affiliated Hospital of Sun Yat-sen University between January 2003 and December 2022. We recorded their imaging features, clinical characteristics and neonatal outcomes. Additionally, we reviewed relevant studies in the field. RESULTS: In total, 127 cases were identified, including eight from our hospital and 119 from the literature. Most patients (93/127, 73.23%) were of reproductive age, 20-40 years old, and 66% were parous. Maternal hirsutism or virilization (such as deepening voice, acne, facial hair growth and clitoromegaly) was observed in 29.92% (38/127), whereas 59.06% of patients (75/127) were asymptomatic. Abdominal pain was reported in 13 patients due to compression, torsion or combined ectopic pregnancy. The pregnancy luteomas, primarily discovered during the third trimester (79/106, 74.53%), varied in size ranging from 10 mm to 20 cm in diameter. Seventy-five cases were incidentally detected during cesarean section or postpartum tubal ligation, and 39 were identified through imaging or physical examination during pregnancy. Approximately 26.61% of patients had bilateral lesions. The majority of pregnancy luteomas were solid and well-defined (94/107, 87.85%), with 43.06% (31/72) displaying multiple solid and well-circumscribed nodules. Elevated serum androgen levels (reaching values between 1.24 and 1529 times greater than normal values for term gestation) were observed in patients with hirsutism or virilization, with a larger lesion diameter (P < 0.001) and a higher prevalence of bilateral lesions (P < 0.001). Among the female infants born to masculinized mothers, 68.18% (15/22) were virilized. Information of imaging features was complete in 22 cases. Ultrasonography revealed well-demarcated hypoechoic solid masses with rich blood supply in 12 of 19 cases (63.16%). Nine patients underwent magnetic resonance imaging (MRI) or computed tomography (CT), and six exhibited solid masses, including three with multi-nodular solid masses. CONCLUSIONS: Pregnancy luteomas mainly manifest as well-defined, hypoechoic and hypervascular solid masses. MRI and CT are superior to ultrasonography in displaying the imaging features of multiple nodules. Maternal masculinization and solid masses with multiple nodules on imaging may help diagnose this rare disease.


Assuntos
Luteoma , Neoplasias Ovarianas , Recém-Nascido , Feminino , Humanos , Gravidez , Adulto Jovem , Adulto , Luteoma/diagnóstico por imagem , Neoplasias Ovarianas/patologia , Hirsutismo/diagnóstico , Cesárea , Estudos Retrospectivos , Virilismo/etiologia , Virilismo/diagnóstico
4.
Environ Res ; 213: 113504, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35640709

RESUMO

The humic substances (HS) - mediated electron transfer process is of great significance to the reduction and degradation of pollutants and the improvement of soil quality. Different soil conditions lead to different characteristics of HS, resulting in differences in the electron transfer capacity (ETC) of HS. It is unclear how the environmental conditions in soil affect the ETC by affecting on HS. In this study, the response relationship of soil microenvironment, HS and ETC has been studied. The results show that the ETC follows the descending order of: Langshan > Nanchang > Anqing > Beijing > Guilin. There were significant differences in ETC in soil HS in different regions. There were significant differences in electron-donating capacity (EDC) in soil HS in different regions and depths. EDC in soil was higher than electron-accepting capacity (EAC), and on average, are 22.4 times higher than the EAC. The HS components of soils in different regions are different. The most significant differences were in tyrosine-like substances and soluble microbial by-products (SMPs). The five components of the soil HS from Langshan were the most different from those in other regions. There were differences in SMPs and humic-like substances in soils of different depths in Anqing and Guilin. ETC can be affected by the composition of HS components in different regions. The composition of HS at different soil depths in the same regions had little effect on ETC. SMPs can promote ETC and EDC, and tyrosine-like substance can promote EDC. Moisture content, pH and TOC are the main factors affecting the composition of HS components. This results can provide a research basis for the sustainable and safe utilization of agricultural soil.


Assuntos
Substâncias Húmicas , Solo , Agricultura , Elétrons , Substâncias Húmicas/análise , Solo/química , Tirosina
5.
Chin Med Sci J ; 37(1): 44-51, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35256045

RESUMO

Objective To evaluate the gastric microbiome in patients with chronic superficial gastritis (CSG) and intestinal metaplasia (IM) and investigate the influence of Helicobacter pylori (H. pylori) on the gastric microbiome. Methods Gastric mucosa tissue samples were collected from 54 patients with CSG and IM, and the patients were classified into the following four groups based on the state of H. pylori infection and histology: H. pylori-negative CSG (n=24), H. pylori-positive CSG (n=14), H. pylori-negative IM (n=11), and H. pylori-positive IM (n=5). The gastric microbiome was analyzed by 16S rRNA gene sequencing. Results H. pylori strongly influenced the bacterial abundance and diversity regardless of CSG and IM. In H. pylori-positive subjects, the bacterial abundance and diversity were significantly lower than in H. pylori-negative subjects. The H. pylori-negative groups had similar bacterial composition and bacterial abundance. The H. pylori-positive groups also had similar bacterial composition but different bacterial relative abundance. The relative abundance of Neisseria, Streptococcus, Rothia, and Veillonella were richer in the I-HP group than in G-HP group, especially Neisseria (t=175.1, P<0.001). Conclusions The gastric microbial abundance and diversity are lower in H. pylori- infected patients regardless of CSG and IM. Compared to H. pylori-positive CSG group and H. pylori-positive IM, the relative abundance of Neisseria, Streptococcus, Rothia, and Veillonella is higher in H. pylori-positive patients with IM than in H. pylori-positive patients with CSG, especially Neisseria.


Assuntos
Gastrite Atrófica , Microbioma Gastrointestinal , Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Mucosa Gástrica/microbiologia , Gastrite Atrófica/microbiologia , Microbioma Gastrointestinal/genética , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Humanos , Metaplasia , RNA Ribossômico 16S/genética
6.
FASEB J ; 34(2): 2227-2237, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31916632

RESUMO

Cyanidin-3-glucoside (C3G) is a natural pigment, found in many colorful fruits and vegetables. It has many health benefits, including anti-inflammation, cancer prevention, and anti-diabetes. Although C3G is assumed to be an antioxidant, it has been reported to affect cell-matrix adhesions. However, the underlying molecular mechanism is unknown. Here, we show that the expression of talin1, a key regulator of integrins and cell adhesions, negatively correlated with the survival rate of colon cancer patients and that depletion of talin1 inhibited 3D spheroid growth in colon cancer cells. Interestingly, C3G bound to talin and promoted the interaction of talin with ß1A-integrin. Molecular docking analysis shows that C3G binds to the interface of the talin-ß-integrin complex, acting as an allosteric regulator and altering the interaction between talin and integrin. Moreover, C3G promoted colon cancer cell attachment to fibronectin. While C3G had no significant effect on colon cancer cell proliferation, it significantly inhibited 3D spheroid growth in fibrin gel assays. Since C3G has no or very low toxicity, it could be potentially used for colon cancer prevention or therapy.


Assuntos
Antocianinas/farmacocinética , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo , Glucosídeos/farmacocinética , Proteínas de Neoplasias , Talina , Animais , Células CHO , Técnicas de Cultura de Células , Neoplasias do Colo/química , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Cricetinae , Cricetulus , Células HCT116 , Humanos , Simulação de Dinâmica Molecular , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Talina/química , Talina/metabolismo
7.
BMC Immunol ; 21(1): 40, 2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32631218

RESUMO

BACKGROUND: Outcome prediction for patients with sepsis may be conductive to early aggressive interventions. Numerous biomarkers and multiple scoring systems have been utilized in predicting outcomes, however, these tools were either expensive or inconvenient. We performed a meta-analysis to evaluate the prognostic role of red blood cell distribution width (RDW) in patients with sepsis. METHODS: The online databases of Embase, Web of science, Pubmed, Corchrane library, Chinese Wanfang database, CNKI database were systematically searched from the inception dates to June, 24th, 2020, using the keywords red cell distribution width and sepsis. The odds ratio (OR) or Hazards ratio (HR) with corresponding 95% confidence intervals (95%CI) were pooled to evaluate the association between baseline RDW and sepsis. A random-effects model was used to pool the data, and statistical heterogeneity between studies was evaluated using the I2 statistic. Sensitivity and subgroup analyses were performed to detect the publication bias and origin of heterogeneity. RESULTS: Eleven studies with 17,961 patients with sepsis were included in the meta-analysis. The pooled analyses indicated that increased baseline RDW was associated with mortality (HR = 1.14, 95%CI 1.09-1.20, Z = 5.78, P < 0.001) with significant heterogeneity (I2 = 80%, Pheterogeneity < 0.001). Similar results were found in the subgroup analysis stratified by site of infection, comorbidity, Newcastle-Ottawa Scale (NOS) score, study design, patients' country. The predefined subgroup analysis showed that NOS score may be the origin of heterogeneity. CONCLUSIONS: For patients with sepsis, baseline RDW may be a useful predictor of mortality, patients with increased RDW are more likely to have higher mortality.


Assuntos
Eritrócitos/patologia , Sepse/diagnóstico , Biomarcadores , Índices de Eritrócitos , Humanos , Valor Preditivo dos Testes , Prognóstico , Sepse/mortalidade , Análise de Sobrevida
8.
FASEB J ; 33(1): 631-642, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30040488

RESUMO

Phosphatidylinositol 4-phosphate 5-kinase type I γ (PIPKIγ90) regulates cell migration, invasion, and metastasis. However, it is unknown how cellular signals regulate those processes. Here, we show that cyclin-dependent kinase 5 (Cdk5), a protein kinase that regulates cell migration and invasion, phosphorylates PIPKIγ90 at S453, and that Cdk5-mediated PIPKIγ90 phosphorylation is essential for cell invasion. Moreover, Cdk5-mediated phosphorylation down-regulates the activity of PIPKIγ90 and the secretion of fibronectin, an extracellular matrix protein that regulates cell migration and invasion. Furthermore, inhibition of PIPKIγ activity with the chemical inhibitor UNC3230 suppresses fibronectin secretion in a dose-dependent manner, whereas depletion of Cdk5 enhances fibronectin secretion. With total internal reflection fluorescence microscopy, we found that secreted fibronectin appears as round dots, which colocalize with Tks5 and CD9 but not with Zyxin. These data suggest that Cdk5-mediated PIPKIγ90 phosphorylation regulates cell invasion by controlling PIPKIγ90 activity and fibronectin secretion.-Li, L., Kolodziej, T., Jafari, N., Chen, J., Zhu, H., Rajfur, Z., Huang, C. Cdk5-mediated phosphorylation regulates phosphatidylinositol 4-phosphate 5-kinase type I γ 90 activity and cell invasion.


Assuntos
Neoplasias da Mama/patologia , Quinase 5 Dependente de Ciclina/metabolismo , Fibronectinas/metabolismo , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Quinase 5 Dependente de Ciclina/genética , Feminino , Fibronectinas/genética , Humanos , Invasividade Neoplásica , Fosforilação , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Transdução de Sinais , Células Tumorais Cultivadas
9.
Appl Microbiol Biotechnol ; 104(1): 277-289, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31728583

RESUMO

The most wide-spread "hostile" environmental factor for marine microorganisms is low temperature, which is usually accompanied by high hydrostatic pressure (HHP). Metabolic mechanisms of marine microorganisms adapting to prolonged low temperature under HHP remain to be clarified. To reveal the underlying metabolic mechanisms, we performed NMR-based metabolomic analysis of aqueous extracts derived from a psychrotolerant Microbacterium sediminis YLB-01, which was isolated from deep-sea sediment and possess great biotechnology potentials. The YLB-01 cells were firstly cultivated at the optimal condition (28 °C, 0.1 MPa) for either 18 h (logarithmic phase) or 24 h (stationary phase), then continually cultivated at either 28 °C or 4 °C under HHP (30 MPa) for 7 days. The cells cultivated at low temperature, which experienced cold stress, were distinctly distinguished from those at normal temperature. Cold stress primarily induced metabolic changes in amino acid metabolism and carbohydrate metabolism. Furthermore, the logarithmic and stationary phase cells cultivated at low temperature exhibited distinct metabolic discrimination, which was mostly reflected in the significantly disturbed carbohydrate metabolism. The logarithmic phase cells displayed suppressed TCA cycle, while the stationary phase cells showed decreased pyruvate and increased lactate. In addition, we performed transcriptome analysis for the stationary phase cells to support the metabolomic analysis. Our results suggest that the cold adaptation of the psychrotroph YLB-01 is closely associated with profoundly altered amino acid metabolism and carbohydrate metabolism. Our work provides a mechanistic understanding of the metabolic adaptation of marine psychrotrophs to prolonged low temperature under HHP.


Assuntos
Actinobacteria/metabolismo , Adaptação Fisiológica , Temperatura Baixa , Pressão Hidrostática , Metabolômica , Actinobacteria/genética , Actinobacteria/crescimento & desenvolvimento , Aminoácidos/metabolismo , Organismos Aquáticos/genética , Organismos Aquáticos/metabolismo , Metabolismo dos Carboidratos , Ciclo do Ácido Cítrico , Resposta ao Choque Frio , Perfilação da Expressão Gênica , Sedimentos Geológicos/microbiologia
10.
J Cell Sci ; 129(19): 3661-3674, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27694340

RESUMO

Talin binds to ß-integrin tails to activate integrins, regulating cell migration, invasion and metastasis. There are two talin genes, TLN1 and TLN2, encoding talin1 and talin2, respectively. Talin1 regulates focal adhesion dynamics, cell migration and invasion, whereas the biological function of talin2 is not clear and, indeed, talin2 has been presumed to function redundantly with talin1. Here, we show that talin2 has a much stronger binding to ß-integrin tails than talin1. Replacement of talin2 Ser339 with Cys significantly decreased its binding to ß1-integrin tails to a level comparable to that of talin1. Talin2 localizes at invadopodia and is indispensable for the generation of traction force and invadopodium-mediated matrix degradation. Ablation of talin2 suppressed traction force generation and invadopodia formation, which were restored by re-expressing talin2 but not talin1. Furthermore, re-expression of wild-type talin2 (but not talin2S339C) in talin2-depleted cells rescued development of traction force and invadopodia. These results suggest that a strong interaction of talin2 with integrins is required to generate traction, which in turn drives invadopodium-mediated matrix degradation, which is key to cancer cell invasion.


Assuntos
Matriz Extracelular/metabolismo , Talina/metabolismo , Animais , Fenômenos Biomecânicos , Células CHO , Bovinos , Linhagem Celular Tumoral , Movimento Celular , Cricetinae , Cricetulus , Adesões Focais/metabolismo , Humanos , Integrina beta1/metabolismo , Podossomos/metabolismo , Ligação Proteica , Isoformas de Proteínas/metabolismo
11.
Zhongguo Dang Dai Er Ke Za Zhi ; 20(11): 911-916, 2018 Nov.
Artigo em Zh | MEDLINE | ID: mdl-30477621

RESUMO

OBJECTIVE: To study the correlation of dynamic change in serum 25-hydroxy vitamin D [25(OH)D] level with the disease severity and related laboratory markers in infants/toddlers with severe pneumonia. METHODS: A total of 132 infants/toddlers with severe pneumonia who were hospitalized between March 2017 and March 2018 were enrolled as the severe pneumonia group. According to the disease severity on admission and after one week of treatment, they were further divided into non-critical group (41 children on admission and 78 after one week of treatment), critical group (59 children on admission and 35 after one week of treatment), and extremely critical group (32 children on admission and 19 after one week of treatment). A total of 142 infants/toddlers who underwent physical examination during the same period of time were enrolled as the healthy control group. The serum levels of 25(OH)D, procalcitonin (PCT), and N-terminal pro-brain natriuretic peptide (NT-proBNP) were measured on admission and after one week of treatment for the severe pneumonia group, and the serum level of 25(OH)D was measured on admission for the healthy control group. According to the 25(OH)D level after one week of treatment, the children with severe pneumonia were divided into increased vitamin D (VD) group with 81 children and reduced VD group with 51 children, and a comparative analysis and a correlation analysis were performed. RESULTS: The severe pneumonia group had a significantly lower mean 25(OH)D level than the healthy control group (P<0.05), and all the three subgroups of different severities had significantly lower 25(OH)D level than the healthy control group (P<0.05). On admission and after one week of treatment, the non-critical group had a significantly higher 25(OH)D level than the critical and extremely critical groups (P<0.01), and the critical group had a significantly higher 25(OH)D level than the extremely critical group (P<0.05). The extremely critical and critical groups had significantly higher serum levels of PCT and NT-proBNP than the non-critical group on admission and after one week of treatment (P<0.05). After one week of treatment, compared with the reduced VD group, the increased VD group had a significantly less serious condition. At discharge, the increased VD group had a significantly better outcome compared with the reduced VD group (P<0.01). In the children with severe pneumonia, the change value of serum 25(OH)D level after treatment was negatively correlated with the change values of PCT and NT-proBNP (r=-0.597 and -0.404 respectively; P<0.01). CONCLUSIONS: The change in VD level is correlated with the severity of severe pneumonia in infants/toddlers and can be used as an index for disease monitoring. VD supplementation may help with disease recovery.


Assuntos
Pneumonia , Deficiência de Vitamina D , Calcifediol , Pré-Escolar , Humanos , Lactente , Pró-Calcitonina , Vitamina D
12.
Zhongguo Dang Dai Er Ke Za Zhi ; 20(7): 559-562, 2018 Jul.
Artigo em Zh | MEDLINE | ID: mdl-30022758

RESUMO

OBJECTIVE: To study the clinical value of red blood cell distribution width (RDW) in the early prediction of acute kidney injury (AKI) in children with sepsis. METHODS: A total of 126 children with sepsis were divided into an AKI group (n=66) and a non-AKI group (n=60) according to the presence or absence of AKI. These patients were also classified into high-RDW and low-RDW groups according to the mean RDW. The groups were compared in terms of age, male-to-female ratio, body mass index (BMI), Acute Physiology and Chronic Health Evaluation II (APACHE II) score, Sequential Organ Failure Assessment (SOFA) score, serum blood urea nitrogen (BUN), creatinine (Cr), uric acid (UA), serum C-reactive protein (CRP), and routine blood test results. Independent factors associated with RDW were analyzed by multiple linear regression. RESULTS: Age, male-to-female ratio, BMI, CRP, SOFA score, and APACHE II score did not differ significantly between the AKI and non-AKI groups (P>0.05), but the AKI group had significantly higher BUN, Cr, UA, and RDW levels than the non-AKI group (P<0.05). Age, male-to-female ratio, and BMI did not differ significantly between the high-RDW and low-RDW groups (P>0.05), but the high-RDW group had significantly higher BUN, Cr, UA, CRP, SOFA score, APACHE II score, Hb, and mean corpuscular volume (MCV) than the low-RDW group (P<0.05). The multiple linear regression analysis showed that age, sex, APACHE II score, Cr, Hb, and MCV were independent factors associated with RDW. CONCLUSIONS: RDW has a certain clinical value in the early prediction of AKI in children with sepsis.


Assuntos
Injúria Renal Aguda/sangue , Eritrócitos/citologia , Sepse/sangue , APACHE , Injúria Renal Aguda/diagnóstico , Adolescente , Criança , Pré-Escolar , Creatinina/sangue , Índices de Eritrócitos , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos , Sepse/diagnóstico
13.
J Biol Chem ; 291(49): 25729-25741, 2016 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-27780861

RESUMO

Phosphatidylinositol 4-phosphate 5-kinase type I γ (PIPKIγ90) ubiquitination and subsequent degradation regulate focal adhesion assembly, cell migration, and invasion. However, it is unknown how upstream signals control PIPKIγ90 ubiquitination or degradation. Here we show that p70S6K1 (S6K1), a downstream target of mechanistic target of rapamycin (mTOR), phosphorylates PIPKIγ90 at Thr-553 and Ser-555 and that S6K1-mediated PIPKIγ90 phosphorylation is essential for cell migration and invasion. Moreover, PIPKIγ90 phosphorylation is required for the development of focal adhesions and invadopodia, key machineries for cell migration and invasion. Surprisingly, substitution of Thr-553 and Ser-555 with Ala promoted PIPKIγ90 ubiquitination but enhanced the stability of PIPKIγ90, and depletion of S6K1 also enhanced the stability of PIPKIγ90, indicating that PIPKIγ90 ubiquitination alone is insufficient for its degradation. These data suggest that S6K1-mediated PIPKIγ90 phosphorylation regulates cell migration and invasion by controlling PIPKIγ90 degradation.


Assuntos
Movimento Celular/fisiologia , Adesões Focais/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Proteólise , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Ubiquitinação/fisiologia , Animais , Células CHO , Cricetinae , Cricetulus , Adesões Focais/genética , Humanos , Fosforilação/fisiologia , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Proteínas Quinases S6 Ribossômicas 70-kDa/genética , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
14.
Circulation ; 132(24): 2334-44, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26399659

RESUMO

BACKGROUND: Integrins are heterodimeric (α/ß) membrane proteins that play fundamental roles in many biological processes, for example, cell adhesion and spreading, which are important for platelet function and hemostasis. The molecular mechanism that regulates integrin activation is not completely understood. METHODS AND RESULTS: Here, we show that VPS33B, a member of the Sec1/Munc18 family, binds directly to the integrin ß subunit. Overexpression of VPS33B in Chinese hamster ovary cells potentiated αIIbß3 outside-in signaling but not inside-out signaling. Platelets, from megakaryocyte- and platelet-specific VPS33B conditional knockout mice, had normal morphology, yet their spreading on fibrinogen was impaired and they failed to support clot retraction. Platelet aggregation and ATP secretion in response to low-dose agonists were reduced in the VPS33B knockout mice. αIIbß3-mediated endocytosis of fibrinogen was also defective. Tail bleeding times and times to occlusion in an FeCl3-induced thrombosis model were prolonged in the VPS33B knockout mice. Furthermore, VPS33B acted upstream of the RhoA-ROCK-MLC and Rac1-dependent pathways that lead to clot retraction and cell spreading, respectively. CONCLUSIONS: Our work demonstrates that vesicular trafficking complexes, containing VPS33B, are a novel class of modifiers of integrin function. Our data also provide insights into the molecular mechanism and treatment of arthrogryposis, renal dysfunction, and cholestasis syndrome.


Assuntos
Hemostasia/fisiologia , Ativação Plaquetária/fisiologia , Trombose/metabolismo , Proteínas de Transporte Vesicular/biossíntese , Animais , Células CHO , Proteínas de Transporte/metabolismo , Cricetinae , Cricetulus , Integrinas/metabolismo , Camundongos , Camundongos Knockout , Transporte Proteico/fisiologia
15.
J Cell Sci ; 126(Pt 12): 2617-28, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23572508

RESUMO

Phosphatidylinositol 4-phosphate 5-kinase type I γ (PIPKIγ90) binds talin and localizes at focal adhesions (FAs). Phosphatidylinositol (4,5)-bisphosphate (PIP2) generated by PIPKIγ90 is essential for FA formation and cell migration. On the other hand, PIPKIγ90 and the ß-integrin tail compete for overlapping binding sites on talin. Enhanced PIPKIγ90-talin interaction suppresses talin binding to the ß-integrin. It is unknown how PIPKIγ90 is removed from the PIPKIγ90-talin complex after on-site PIP2 production during cell migration. Here we show that PIPKIγ90 is a substrate for HECTD1, an E3 ubiquitin ligase regulating cell migration. HECTD1 ubiquitinated PIPKIγ90 at lysine 97 and resulted in PIPKIγ90 degradation. Expression of the mutant PIPKIγ90(K97R) enhanced PIP2 and PIP3 production, inhibited FA assembly and disassembly and inhibited cancer cell migration, invasion and metastasis. Interestingly, mutation at tryptophan 647 abolished the inhibition of PIPKIγ90(K97R) on FA dynamics and partially rescued cancer cell migration and invasion. Thus, cycling PIPKIγ90 ubiquitylation by HECTD1 and consequent degradation remove PIPKIγ90 from talin after on-site PIP2 production, providing an essential regulatory mechanism for FA dynamics and cell migration.


Assuntos
Movimento Celular/fisiologia , Adesões Focais/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação/fisiologia , Animais , Células CHO , Linhagem Celular , Cricetinae , Cricetulus , Células HEK293 , Humanos , Cadeias beta de Integrinas/metabolismo , Lisina/metabolismo , Invasividade Neoplásica , Metástase Neoplásica , Fosfatidilinositol 4,5-Difosfato/metabolismo , Talina/metabolismo
16.
FASEB J ; 28(2): 861-70, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24277575

RESUMO

Autotaxin (ATX) is a secreted lysophospholipase D (lysoPLD) that binds to integrin adhesion receptors. We dissected the roles of integrin binding and lysoPLD activity in stimulation of human breast cancer and mouse aortic vascular smooth muscle cell migration by ATX. We compared effects of wild-type human ATX, catalytically inactive ATX, an integrin binding-defective ATX variant with wild-type lysoPLD activity, the isolated ATX integrin binding N-terminal domain, and a potent ATX selective lysoPLD inhibitor on cell migration using transwell and single-cell tracking assays. Stimulation of transwell migration was reduced (18 or 27% of control, respectively) but not ablated by inactivation of integrin binding or inhibition of lysoPLD activity. The N-terminal domain increased transwell migration (30% of control). ATX lysoPLD activity and integrin binding were necessary for a 3.8-fold increase in the fraction of migrating breast cancer cell step velocities >0.7 µm/min. ATX increased the persistent directionality of single-cell migration 2-fold. This effect was lysoPLD activity independent and recapitulated by the integrin binding N-terminal domain. Integrin binding enables uptake and intracellular sequestration of ATX, which redistributes to the front of migrating cells. ATX binding to integrins and lysoPLD activity therefore cooperate to promote rapid persistent directional cell migration.


Assuntos
Movimento Celular/fisiologia , Integrinas/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Adesão Celular/genética , Adesão Celular/fisiologia , Linhagem Celular , Movimento Celular/genética , Humanos , Lisofosfolipídeos/metabolismo , Microscopia de Fluorescência
17.
J Nat Prod ; 78(6): 1294-9, 2015 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-26039736

RESUMO

Chemical investigation of the marine-sponge-derived fungus Penicillium adametzioides AS-53 resulted in the identification of two new bisthiodiketopiperazine derivatives, adametizines A (1) and B (2), from cultivation in a liquid potato-dextrose broth (PDB) culture medium, whereas two new acorane sesquiterpenes, adametacorenols A (3) and B (4), were isolated from a rice solid culture medium. The structures of these compounds were elucidated on the basis of spectroscopic analysis. The absolute configuration of compound 1 was determined by X-ray crystallographic analysis, and that of 3 was determined by modified Mosher's method. Compound 1 exhibited lethality against brine shrimp (Artemia salina) with an LD50 value of 4.8 µM and inhibitory activities against Staphyloccocus aureus, Aeromonas hydrophilia, Vibrio spp. V. harveyi and V. parahaemolyticus, and Gaeumannomyces graminis with minimum inhibitory concentration values of 8, 8, 32, 8, and 16 µg/mL, respectively. Chlorination at C-7 significantly increased the brine shrimp lethality and antimicrobial activity of the bisthiodiketopiperazines.


Assuntos
Antibacterianos/isolamento & purificação , Dicetopiperazinas/isolamento & purificação , Penicillium/química , Sesquiterpenos/isolamento & purificação , Aeromonas/efeitos dos fármacos , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Artemia/efeitos dos fármacos , Cristalografia por Raios X , Meios de Cultura , Dicetopiperazinas/química , Dicetopiperazinas/farmacologia , Biologia Marinha , Testes de Sensibilidade Microbiana , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Poríferos/microbiologia , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Vibrio/efeitos dos fármacos
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(12): 3422-6, 2015 Dec.
Artigo em Zh | MEDLINE | ID: mdl-26964222

RESUMO

Tea is one of the most popular beverages in the world. For the contribution to the taste and healthy functions of tea, amino acids and catechins are important components. Among different kinds of black teas in the world, Keemun black tea has the famous and specific fragrance, "Keemun aroma". During the processing procedure of Keemun black tea, the contents of amino acids and catechins changed greatly, and the differences of these concentrations during processing varied significantly. However, a rapid and dynamic determination method during the processing procedure was not existed up to now. In order to find out a rapid determination method for the contents of amino acids and catechins during the processing procedure of Keemun black tea, the materials of fresh leaves, withered leaves, twisted leaves, fermented leaves, and crude tea (after drying) were selected to acquire their corresponding near infrared spectroscopy and obtain their contents of amino acids and catechins by chemical analysis method. The original spectra data were preprocessed by the Standard Normal Variate Transformation (SNVT) method. And the model of Near Infrared (NIR) spectroscopy with the contents of amino acids and catechins combined with Synergy Interval Partial Least squares (Si-PLS) was established in this study. The correlation coefficients and the cross validation root mean square error are treated as the efficient indexes for evaluating models. The results showed that the optimal prediction model of amino acids by Si-PLS contained 20 spectral intervals combined with 4 subintervals and 9 principal component factors. The correlation coefficient and the root mean square error of the calibration set were 0. 955 8 and 1. 768, respectively; the correlation coefficient and the root mean square error of the prediction set were 0. 949 5 and 2. 16, respectively. And the optimal prediction model of catechins by Si-PLS contained 20 spectral intervals combined with 3 subintervals and 10 principal component factors. The correlation coefficient and the root mean square error of the calibration set were 0. 940 1 and 1. 22, respectively; the correlation coefficient and the root mean square error of the prediction set were 0. 938 5 and 1. 17, respectively. The results showed that the established models had good accuracy which could provide a theoretical foundation for the online determination of tea chemical components during processing.


Assuntos
Aminoácidos/química , Catequina/química , Chá/química , Camellia sinensis/química , Fermentação , Análise dos Mínimos Quadrados , Modelos Teóricos , Folhas de Planta/química , Espectroscopia de Luz Próxima ao Infravermelho
19.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(9): 927-31, 2015 Sep.
Artigo em Zh | MEDLINE | ID: mdl-26412172

RESUMO

OBJECTIVE: To explore the risk factors for coronary artery lesions (CAL) secondary to Kawasaki disease (KD) in children. METHODS: The medical data of 895 children with KD were retrospectively reviewed. The patients were classified into two groups according to the presence of CAL: CAL (n=284) and control (n=611). The clinical and laboratory indices were compared between the two groups. The risk factors for the development of CAL in children with KD were identified by multiple logistic regression analysis. RESULTS: Male gender (OR=1.712), occurrence of non-CAL complications (OR=2.028), atypical KD (OR=3.655), intravenous immunoglobulin (IVIG) resistance (OR=2.912), more than 5 days of fever duration before IVIG treatment (OR=1.350), and increased serum procalcitonin (PCT) level (OR=1.068) were the independent risk factors for the development of CAL in children with KD (P<0.05), whereas increased serum albumin (Alb) level was a protective factor (OR=0.931, P<0.05). The areas under the receiver operating characteristic curve of serum PCT and ALB for prediction of the development of CAL in children with KD were 0.631 and 0.558, respectively. CONCLUSIONS: Male gender, atypical KD, occurrence of other non-CAL complications, long duration of fever and IVIG resistance are associated with an increased risk for CAL in children with KD. Serum PCT and ALB have little value in the prediction of CAL in children with KD.


Assuntos
Doença da Artéria Coronariana/etiologia , Síndrome de Linfonodos Mucocutâneos/complicações , Adolescente , Calcitonina/sangue , Peptídeo Relacionado com Gene de Calcitonina , Criança , Pré-Escolar , Feminino , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Lactente , Masculino , Precursores de Proteínas/sangue , Fatores de Risco
20.
J Nat Prod ; 77(8): 1921-7, 2014 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-25105722

RESUMO

Six new disulfide-bridged diketopiperazine derivatives, brocazines A-F (1-6), along with one known analogue (7), were isolated and identified from the cytotoxic extract of Penicillium brocae MA-231, a fungus obtained from the fresh tissue of the marine mangrove plant Avicennia marina. The structures of these compounds were established on the basis of detailed interpretation of NMR and mass spectroscopic data. X-ray crystallographic analysis confirmed the structure of 1 and established the structure and absolute configuration of 5, while the absolute configurations for compounds 1, 4, and 6 were deduced by comparison of the CD data with those of 5. Compounds 1, 2, 5, and 6 showed cytotoxic activities against several tumor cell lines.


Assuntos
Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Avicennia/microbiologia , Dicetopiperazinas/isolamento & purificação , Dicetopiperazinas/farmacologia , Penicillium/química , Antineoplásicos/química , China , Cristalografia por Raios X , Dicetopiperazinas/química , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Biologia Marinha , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular
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