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1.
Cell ; 184(16): 4299-4314.e12, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34297923

RESUMO

Retinal ganglion cells (RGCs) are the sole output neurons that transmit visual information from the retina to the brain. Diverse insults and pathological states cause degeneration of RGC somas and axons leading to irreversible vision loss. A fundamental question is whether manipulation of a key regulator of RGC survival can protect RGCs from diverse insults and pathological states, and ultimately preserve vision. Here, we report that CaMKII-CREB signaling is compromised after excitotoxic injury to RGC somas or optic nerve injury to RGC axons, and reactivation of this pathway robustly protects RGCs from both injuries. CaMKII activity also promotes RGC survival in the normal retina. Further, reactivation of CaMKII protects RGCs in two glaucoma models where RGCs degenerate from elevated intraocular pressure or genetic deficiency. Last, CaMKII reactivation protects long-distance RGC axon projections in vivo and preserves visual function, from the retina to the visual cortex, and visually guided behavior.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Citoproteção , Células Ganglionares da Retina/patologia , Visão Ocular , Animais , Axônios/efeitos dos fármacos , Axônios/patologia , Encéfalo/patologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Dependovirus/metabolismo , Modelos Animais de Doenças , Ativação Enzimática/efeitos dos fármacos , Glaucoma/genética , Glaucoma/patologia , Camundongos Endogâmicos C57BL , Neurotoxinas/toxicidade , Traumatismos do Nervo Óptico/patologia , Transdução de Sinais
2.
Mol Cancer ; 21(1): 103, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35459184

RESUMO

BACKGROUND: Multidrug resistance (MDR) mediated by ATP binding cassette subfamily B member 1 (ABCB1/P-gp) is a major cause of cancer chemotherapy failure, but the regulation mechanisms are largely unknown. METHODS: Based on single gene knockout, we studied the regulation of CDK6-PI3K axis on ABCB1-mediated MDR in human cancer cells. CRISPR/Cas9 technique was performed in KB-C2 cells to knockout cdk6 or cdk4 gene. Western blot, RT-PCR and transcriptome analysis were performed to investigate target gene deletion and expression of critical signaling factors. The effect of cdk4 or cdk6 deficiency on cell apoptosis and the cell cycle was analyzed using flow cytometry. In vivo studies were performed to study the sensitivity of KB-C2 tumors to doxorubicin, tumor growth and metastasis. RESULTS: Deficiency of cdk6 led to remarkable downregulation of ABCB1 expression and reversal of ABCB1-mediated MDR. Transcriptomic analysis revealed that CDK6 knockout regulated a series of signaling factors, among them, PI3K 110α and 110ß, KRAS and MAPK10 were downregulated, and FOS-promoting cell autophagy and CXCL1-regulating multiple factors were upregulated. Notably, PI3K 110α/110ß deficiency in-return downregulated CDK6 and the CDK6-PI3K axis synergizes in regulating ABCB1 expression, which strengthened the regulation of ABCB1 over single regulation by either CDK6 or PI3K 110α/110ß. High frequency of alternative splicing (AS) of premature ABCB1 mRNA induced by CDK6, CDK4 or PI3K 110α/110ß level change was confirmed to alter the ABCB1 level, among them 10 common skipped exon (SE) events were found. In vivo experiments demonstrated that loss of cdk6 remarkably increased the sensitivity of KB-C2 tumors to doxorubicin by increasing drug accumulation of the tumors, resulting in remarkable inhibition of tumor growth and metastasis, as well as KB-C2 survival in the nude mice. CONCLUSIONS: CDK6-PI3K as a new target signaling axis to reverse ABCB1-mediated MDR is reported for the first time in cancers. Pathways leading to inhibition of cancer cell proliferation were revealed to be accompanied by CDK6 deficiency.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP , Antineoplásicos , Quinase 6 Dependente de Ciclina , Neoplasias , Fosfatidilinositol 3-Quinases , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Quinase 6 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/metabolismo , Doxorrubicina/farmacologia , Resistência a Múltiplos Medicamentos/genética , Resistência a Múltiplos Medicamentos/fisiologia , Resistencia a Medicamentos Antineoplásicos/genética , Resistencia a Medicamentos Antineoplásicos/fisiologia , Humanos , Camundongos , Camundongos Nus , Neoplasias/tratamento farmacológico , Neoplasias/genética , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo
3.
FASEB J ; 34(6): 7540-7560, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32301538

RESUMO

The vascular endothelium has been discovered in the past several years to be important in shaping the cellular immune response. During the immune response the vascular endothelium is constantly perturbed by biologically potent molecules, including the complement activation peptides, C3a and C5a. Despite the importance of C3a and C5a in inflammation and immunity, their role in modulating lymphocyte function via activation of vascular endothelial cells is unknown. Accordingly, we investigated the regulated expression of the C3a and C5a receptors (complement anaphylatoxin C3a receptor [C3aR] and complement anaphylatoxin C5a receptor 1 [C5aR1]) on human umbilical vascular endothelial cells (HUVECs) and examined how C3a or C5a activation of HUVECs affects the activation and polarization of lymphatic cells. Our findings demonstrated that C3a and C5a increase C3aR and C5aR1 expression by HUVECs as well as directing their cellular transmigration and spreading through transwell filters. Moreover, C3a- or C5a-stimulated endothelial cells: (1) caused activation of B-lymphoblasts with significant increase in Fas Ligand (CD95L) (FasL), CD69, and IL-R1 expression, and (2) skewed T-lymphoblast cells toward a Th1 subtype, (CD4+ /CCR5+ ) that correlated with significant increase of IFN-γ. Collectively, these data indicate that C3a and C5a signaling is important in the activation and polarization of lymphocytes as they traffic through the vascular endothelium during the immune response.


Assuntos
Anafilatoxinas/imunologia , Linfócitos B/imunologia , Complemento C3a/imunologia , Complemento C5a/imunologia , Peptídeos/imunologia , Linfócitos T/imunologia , Células Cultivadas , Ativação do Complemento/imunologia , Endotélio Vascular/imunologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação/imunologia , Receptor da Anafilatoxina C5a/imunologia , Receptores de Complemento/imunologia , Transdução de Sinais/imunologia
4.
Mol Cancer ; 19(1): 10, 2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31952518

RESUMO

BACKGROUND: PI3K/AKT is a vital signaling pathway in humans. Recently, several PI3K/AKT inhibitors were reported to have the ability to reverse cancer multidrug resistance (MDR); however, specific targets in the PI3K/AKT pathways and the mechanisms associated with MDR have not been found because many of the inhibitors have multiple targets within a large candidate protein pool. AKT activation is one presumed mechanism by which MDR develops during cancer treatment. METHODS: The effects of inhibiting PI3K 110α and 110ß by BAY-1082439 treatment and CRISPR/Cas9 knockout were examined to determine the possible functions of BAY-1082439 and the roles of PI3K 110α and 110ß in the reversal of MDR that is mediated by the downregulation of P-gp and BCRP. Inhibition of AKT with GSK-2110183 showed that the downregulation of P-gp and BCRP is independent of generalized AKT inactivation. Immunofluorescence, immunoprecipitation, MTT, flow cytometry and JC-1 staining analyses were conducted to study the reversal of MDR that is mediated by P-gp and BCRP in cancer cells. An ATPase assay and a structural analysis were also used to analyze the potential mechanisms by which BAY-1082439 specifically targets PI3K 110α and 110ß and nonspecifically influences P-gp and BCRP. RESULTS: By inhibiting the activation of the PI3K 110α and 110ß catalytic subunits through both the administration of BAY-1082439 and the CRISPR/Cas9 deletion of Pik3ca and Pik3cb, the ATP-binding cassette transporters P-gp/ABCB1 and BCRP/ABCG2 were downregulated, thereby reestablishing the drug sensitivity of human epidermoid carcinoma and non-small cell lung cancer (NSCLC) MDR cells. Inhibition of AKT did not reverse the MDR mediated by P-gp or BCRP. The ABC family proteins and AKT may play MDR-enhancing roles independently. CONCLUSIONS: The reversal of the dual functions of ABC-transporter-mediated and AKT-activation-enhanced MDR through the inhibition or knockout of PI3K 110α or 110ß promises to improve current strategies based on combined drug treatments to overcome MDR challenges.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Carcinoma de Células Escamosas/tratamento farmacológico , Classe I de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Proteínas de Neoplasias/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas de Neoplasias/genética , Células Tumorais Cultivadas
5.
Appl Opt ; 59(13): 4165-4170, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32400694

RESUMO

We utilize the space-variant structure of the human fovea as a basis for a novel, to the best of our knowledge, foveal approach based on optical-phases array (OPA). This approach can be used to solve issues in 3D imaging and achieve a large field of view and high resolution with real-time application. A foveal scanning model based on the OPA is established. Simulations and experiments are performed to verify the models and illustrate the advantages of foveal scanning compared with traditional raster scanning. Simulations agree well with the theory, and the foveal approach has higher efficiency than traditional raster scanning. These results can serve as a reference for developing biomimetic sensors that mimic the human eye.


Assuntos
Fóvea Central/fisiologia , Imagem Óptica/instrumentação , Tomografia de Coerência Óptica/instrumentação , Humanos , Modelos Biológicos , Modelos Teóricos , Acuidade Visual
6.
J Immunol ; 198(8): 3237-3244, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28275134

RESUMO

Listeria monocytogenes is an intracellular Gram-positive bacterium that induces expression of type I IFNs (IFN-α/IFN-ß) during infection. These cytokines are detrimental to the host during infection by priming leukocytes to undergo L. monocytogenes-mediated apoptosis. Our previous studies showed that C5aR1-/- and C3aR-/- mice are highly susceptible to L. monocytogenes infection as a result of increased IFN-ß-mediated apoptosis of major leukocyte cell populations, including CD4+ and CD8+ T cells. However, the mechanisms by which C3a and C5a modulate IFN-ß expression during L. monocytogenes infection were not examined in these initial investigations. Accordingly, we report in this article that C5a and C3a suppress IFN-ß production in response to L. monocytogenes via cyclic di-AMP (c-di-AMP), a secondary messenger molecule of L. monocytogenes, in J774A.1 macrophage-like cells and in bone marrow-derived dendritic cells (BMDCs). Moreover, C5a and C3a suppress IFN-ß production by acting through their respective receptors, because no inhibition was seen in C5aR1-/- or C3aR-/- BMDCs, respectively. C5a and C3a suppress IFN-ß production in a manner that is dependent on Bruton's tyrosine kinase, p38 MAPK, and TANK-binding kinase 1 (TBK1), as demonstrated by the individual use of Bruton's tyrosine kinase, p38 MAPK, and TBK1 inhibitors. Pretreatment of cells with C5a and C3a reduced the expression of the IFN-ß signaling molecules DDX41, STING, phosphorylated TBK1, and phosphorylated p38 MAPK in wild-type BMDCs following treatment with c-di-AMP. Collectively, these data demonstrate that C3a and C5a, via direct signaling through their specific receptors, suppress IFN-ß expression by modulation of a distinct innate cytosolic surveillance pathway involving DDX41, STING, and other downstream molecular targets of L. monocytogenes-generated c-di-AMP.


Assuntos
Complemento C3a/imunologia , Complemento C5a/imunologia , Imunidade Inata/imunologia , Interferon beta/imunologia , Listeriose/imunologia , Transdução de Sinais/imunologia , Animais , Western Blotting , Complemento C3a/metabolismo , Complemento C5a/metabolismo , AMP Cíclico , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Interferon beta/biossíntese , Listeria monocytogenes , Listeriose/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
7.
J Cell Mol Med ; 20(7): 1276-86, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26915688

RESUMO

Small guanosine triphosphate (GTP)-binding protein RhoB is an important stress sensor and contributes to the regulation of cytoskeletal organization, cell proliferation and survival. However, whether RhoB is involved in the hypoxic response and action of glucocorticoid (GC) is largely unknown. In this study, we investigated the effects of hypoxia or/and GC on the expression and activition of RhoB in the lung of rats and human A549 lung carcinoma cells, and further studied its mechanism and significance. We found that hypoxia and dexamethasone (Dex), a synethic GC, not only significantly increased the expression and activation of RhoB independently but also coregulated the expresion of RhoB in vitro and in vivo. Up-regulation of RhoB by hypoxia was in part through stabilizing the RhoB mRNA and protein. Inhibiting hypoxia-activated hypoxia-inducible transcription factor-1α (HIF-1α), c-Jun N-terminal kinase (JNK) or extracellular signal-regulated kinase (ERK) with their specific inhibitors significantly decreased hypoxia-induced RhoB expression, indicating that HIF-1α, JNK and ERK are involved in the up-regulation of RhoB in hypoxia. Furthermore, we found that knockdown of RhoB expression by RhoB siRNA not only significantly reduced hypoxia-enhanced cell migration and cell survival in hypoxia but also increased the sensitivity of cell to paclitaxel (PTX), a chemotherapeutic agent, and reduced Dex-enhanced resistance to PTX-chemotherapy in A549 cells. Taken together, the novel data revealed that hypoxia and Dex increased the expression and activation of RhoB, which is important for hypoxic adaptation and hypoxia-accelerated progression of lung cancer cells. RhoB also enhanced the resistance of cell to PTX-chemotherapy and mediated the pro-survival effect of Dex.


Assuntos
Glucocorticoides/farmacologia , Pulmão/metabolismo , Regulação para Cima/efeitos dos fármacos , Proteína rhoB de Ligação ao GTP/metabolismo , Células A549 , Animais , Antineoplásicos/farmacologia , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/genética , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dexametasona/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Pulmão/efeitos dos fármacos , Modelos Biológicos , Estabilidade de RNA/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteína rhoB de Ligação ao GTP/genética
8.
Development ; 138(16): 3569-78, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21771811

RESUMO

Mutations in Drosophila rumi result in a temperature-sensitive loss of Notch signaling. Rumi is a protein O-glucosyltransferase that adds glucose to EGF repeats with a C-X-S-X-P-C consensus sequence. Eighteen of the 36 EGF repeats in the Drosophila Notch receptor contain the consensus O-glucosylation motif. However, the contribution of individual O-glucose residues on Notch to the regulation of Notch signaling is not known. To address this issue, we carried out a mutational analysis of these glucosylation sites and determined their effects on Notch activity in vivo. Our results indicate that even though no single O-glucose mutation causes a significant decrease in Notch activity, all of the glucose residues on Notch contribute in additive and/or redundant fashions to maintain robust signaling, especially at higher temperatures. O-glucose motifs in and around the ligand-binding EGF repeats play a more important role than those in other EGF repeats of Notch. However, a single O-glucose mutation in EGF12 can be compensated by other O-glucose residues in neighboring EGF repeats. Moreover, timecourse cell aggregation experiments using a rumi null cell line indicate that a complete lack of Rumi does not affect Notch-Delta binding at high temperature. In addition, rumi fully suppresses the gain-of-function phenotype of a ligand-independent mutant form of Notch. Our data suggest that, at physiological levels of Notch, the combined effects of multiple O-glucose residues on this receptor allow productive S2 cleavage at high temperatures and thereby serve as a buffer against temperature-dependent loss of Notch signaling.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Glucosiltransferases/metabolismo , Receptores Notch/metabolismo , Transdução de Sinais , Animais , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Regulação da Expressão Gênica no Desenvolvimento , Genoma de Inseto , Glucose/metabolismo , Glucosiltransferases/genética , Mutação , Receptores Notch/genética , Temperatura , Transgenes
9.
Artigo em Inglês | MEDLINE | ID: mdl-38648126

RESUMO

Federated recommender systems (FRSs), with their improved privacy-preserving advantages to jointly train recommendation models from numerous devices while keeping user data distributed, have been widely explored in modern recommender systems (RSs). However, conventional FRSs require transmitting the entire model between the server and clients, which brings a huge carbon footprint for cost-conscious cross-device learning tasks. While several efforts have been dedicated to improving the efficiency of FRSs, it's suboptimal to treat the whole model as the objective of compact design. Besides, current research fails to handle the out-of-vocabulary (OOV) issue in real-world FRSs, where the items only occasionally appear in the testing phase but were not observed during the training process, which is another practical challenge and has not been well studied yet. To this end, we propose a privacy-enhanced federated recommendation framework with shared hash embedding, PrivFR, in cross-device settings, which is an efficient representation mechanism specialized for the embedding parameters without compromising the model capability. Specifically, it represents items in a resource-efficient way by delicately utilizing shared hash embedding and multiple hash functions. As such, it just maintains a small shared pool of hash embedding in local clients, rather than fitting all embedding vectors for each item, which can exactly achieve the dual advantages of conserving resources and handling the OOV issue. What's more, we prove that this mechanism can protect the data privacy of local clients from a theoretical perspective. Extensive experiments show that our method not only effectively reduces storage and communication overheads, but also outperforms state-of-the-art FRSs.

10.
Int J Biol Macromol ; 254(Pt 3): 127892, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37952799

RESUMO

Underwater superoleophobic (UWSO) materials have garnered significant attention in separating oil/water mixtures. But, the majority of these materials are made from non-degradable and non-renewable raw materials, polluting the environment and wasting scarce resources while using them. Against this backdrop, this study aimed to fabricate an environmental-friendly UWSO textile using biobased materials. To achieve this, hydrogel consisting of chitosan (CS) and poly(tannic acid) (PTA) were formed and coated on cotton fabric (CTF) via dip-coating followed by oxidative polymerization. CS&PTA hydrogel endowed the CTF with a rough surface and high surface energy, leading to an UWSO CTF with an underwater oil contact angle as high as 166.84°. The CS&PTA/CTF had excellent separation capability toward various oil/water mixtures, showing separation efficiency above 99.84 % and water flux higher than 23, 999 L m-2 h-1. Moreover, CS&PTA/CTF possessed excellent mechanical and environmental stability with underwater superoleophobicity unchanged after sandpaper friction, ultrasonication, organic solvents, NaCl (m/v, 30 %) solution, and acid/base solution immersion, due to the strong interaction between the hydrogel and cotton fabric generated by the mussel-inspired adhesion owing to the presence of PTA. The fully biobased UWSO CTF exhibits great promising to be an alternative to traditional superwetting materials for separation of oil/water mixtures.


Assuntos
Quitosana , Hidrogéis , Humanos , Caquexia , Têxteis
11.
Front Pharmacol ; 15: 1347750, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38420197

RESUMO

Once hailed as miraculous solutions, antibiotics no longer hold that status. The excessive use of antibiotics across human healthcare, agriculture, and animal husbandry has given rise to a broad array of multidrug-resistant (MDR) pathogens, posing formidable treatment challenges. Antimicrobial resistance (AMR) has evolved into a pressing global health crisis, linked to elevated mortality rates in the modern medical era. Additionally, the absence of effective antibiotics introduces substantial risks to medical and surgical procedures. The dwindling interest of pharmaceutical industries in developing new antibiotics against MDR pathogens has aggravated the scarcity issue, resulting in an exceedingly limited pipeline of new antibiotics. Given these circumstances, the imperative to devise novel strategies to combat perilous MDR pathogens has become paramount. Contemporary research has unveiled several promising avenues for addressing this challenge. The article provides a comprehensive overview of these innovative therapeutic approaches, highlighting their mechanisms of action, benefits, and drawbacks.

12.
Sci Total Environ ; 918: 170507, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38309354

RESUMO

Conveyance and modification of carbon-isotope signals within the karst system remain difficult to constrain, due to the complexity of interactions between multiple components, including precipitation, bedrock, soil, atmosphere, and biota. Cave monitoring is thus critical to understanding both their transport in the karst system and dependence on local hydroclimatic conditions. Jiguan Cave, located in Funiu Mountain in central China, is representative of karst tourist caves with relatively thin epikarst zone. We conducted a comprehensive monitoring program of cave climate from 2018 to 2021 and measured δ13C during 2021 in monthly and heavy-rainfall samples of soil CO2, cave CO2, cave water (drip water and underground river), and underground river outlet. Our results demonstrate synchronous variations between CO2 concentration and δ13CCO2 in both soil and cave air on seasonal time scales. Cave pCO2 and carbon-isotope composition further exhibited a high sensitivity to human respiration with fluctuations of ~2000-3000 ppm within 4 days during the cave closure period in July 2021 without tourists. 13C-depleted isotopic signal of cave air in summer is the mixture of human respiration and soil CO2 which varies as a function of regional hydrological conditions of the summer monsoon during the rainy season with high temperatures and humidity. However, respired CO2 from the overlying soil was expected to be the only principal source of the cave CO2 when the anthropogenic CO2 source was removed. The high seasonal amplitude of cave air δ13CCO2 reflects ventilation dynamics, which leads to a prominent contribution from the external atmosphere during winter. Intriguingly, although the δ13C signal reflects complex vertical processes in the vertical karst profile, a heavy summer rainfall event was related to anomalously high δ13C values of cave water that can be utilized to interpret rainfall intensity and regional hydroclimate.

13.
J Cell Mol Med ; 17(7): 863-72, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23672602

RESUMO

Stomatin is an important lipid raft-associated protein which interacts with membrane proteins and plays a role in the membrane organization. However, it is unknown whether it is involved in the response to hypoxia and glucocorticoid (GC) in alveolar epithelial cells (AEC). In this study we found that hypoxia and dexamethasone (dex), a synthetic GC not only up-regulated the expression of stomatin alone, but also imposed additive effect on the expression of stomatin in A549 cells, primary AEC and lung of rats. Then we investigated whether hypoxia and dex transcriptionally up-regulated the expression of stomatin by reporter gene assay, and found that dex, but not hypoxia could increase the activity of a stomatin promoter-driven reporter gene. Further deletion and mutational studies demonstrated that a GC response element (GRE) within the promoter region mainly contributed to the induction of stomatin by dex. Moreover, we found that hypoxia exposure did not affect membrane-associated actin, but decreased actin in cytoplasm in A549 cells. Inhibiting stomatin expression by stomatin siRNA significantly decreased dense of peripheral actin ring in hypoxia or dex treated A549 cells. Taken all together, these data indicated that dex and/or hypoxia significantly up-regulated the expression of stomatin in vivo and in vitro, which could stabilize membrane-associated actin in AEC. We suppose that the up-regulation of stomatin by hypoxia and dex may enhance the barrier function of alveolar epithelia and mediate the adaptive role of GC to hypoxia.


Assuntos
Actinas/metabolismo , Membrana Celular/metabolismo , Dexametasona/farmacologia , Células Epiteliais/citologia , Proteínas de Membrana/metabolismo , Alvéolos Pulmonares/citologia , Animais , Hipóxia Celular , Linhagem Celular Tumoral , Células Epiteliais/metabolismo , Genes Reporter , Humanos , Neoplasias Pulmonares/metabolismo , Mutagênese Sítio-Dirigida , Regiões Promotoras Genéticas , Ratos , Ratos Sprague-Dawley , Regulação para Cima
14.
J Huazhong Univ Sci Technolog Med Sci ; 33(4): 563-566, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23904378

RESUMO

We performed a retrospective, case-control study to evaluate whether the urine flow acceleration (UFA, mL/s(2)) is superior to maximum uroflow (Qmax, mL/s) in diagnosing bladder outlet obstruction (BOO) in patients with benign prostatic hyperplasia (BPH). In this study, a total of 50 men with BPH (age: 58±12.5 years) and 50 controls (age: 59±13.0 years) were included. A pressure-flow study was used to determine the presence of BOO according to the recommendations of Incontinence Control Society (ICS). The results showed that the UFA and Qmax in BPH group were much lower than those in the control group [(2.05±0.85) vs. (4.60±1.25) mL/s(2) and (8.50±1.05) vs. (13.00±3.35) mL/s] (P<0.001). According to the criteria (UFA<2.05 mL/s(2), Qmax<10 mL/s), the sensitivity and specificity of UFA vs. Qmax in diagnosing BOO were 88%, 75% vs. 81%, 63%. UFA vs. Omax, when compared with the results of P-Q chart (the kappa values in corresponding analysis), was 0.55 vs. 0.35. The prostate volume, post void residual and detrusor pressure at Qmax between the two groups were 28.6±9.8 vs. 24.2±7.6 mL, 60.4±1.4 vs. 21.3±2.5 mL and 56.6±8.3 vs. 21.7±6.1 cmH2O, respectively (P<0.05). It was concluded that the UFA is a useful urodynamic parameter, and is superior to Qmax in diagnosing BOO in patients with BPH.


Assuntos
Hiperplasia Prostática/fisiopatologia , Obstrução do Colo da Bexiga Urinária/diagnóstico , Obstrução do Colo da Bexiga Urinária/fisiopatologia , Urina/fisiologia , Estudos de Casos e Controles , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
15.
IEEE Trans Cybern ; 53(3): 1618-1628, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34499612

RESUMO

Partial multilabel learning (PML) aims to learn from training data, where each instance is associated with a set of candidate labels, among which only a part is correct. The common strategy to deal with such a problem is disambiguation, that is, identifying the ground-truth labels from the given candidate labels. However, the existing PML approaches always focus on leveraging the instance relationship to disambiguate the given noisy label space, while the potentially useful information in label space is not effectively explored. Meanwhile, the existence of noise and outliers in training data also makes the disambiguation operation less reliable, which inevitably decreases the robustness of the learned model. In this article, we propose a prior label knowledge regularized self-representation PML approach, called PAKS, where the self-representation scheme and prior label knowledge are jointly incorporated into a unified framework. Specifically, we introduce a self-representation model with a low-rank constraint, which aims to learn the subspace representations of distinct instances and explore the high-order underlying correlation among different instances. Meanwhile, we incorporate prior label knowledge into the above self-representation model, where the prior label knowledge is regarded as the complement of features to obtain an accurate self-representation matrix. The core of PAKS is to take advantage of the data membership preference, which is derived from the prior label knowledge, to purify the discovered membership of the data and accordingly obtain more representative feature subspace for model induction. Enormous experiments on both synthetic and real-world datasets show that our proposed approach can achieve superior or comparable performance to state-of-the-art approaches.

16.
Int J Biol Macromol ; 236: 123960, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36921823

RESUMO

Biobased poly(lactic acid)/lignin (PLA/lignin) composites are limited by poor mechanical properties resulted from poor compatibility and low interfacial adhesion. Herein, we reported a novel approach to improve compatibility and interfacial adhesion of PLA/lignin composites via reactive compatibilization with epoxidized natural rubber (ENR) as a compatibilizer. Interfacial tension calculation indicated that lignin tended to act as interfacial phase between PLA and ENR, but morphology analysis demonstrated lignin was wrapped with a layer of ENR and dispersed in PLA matrix, which was attributed to the interfacial reaction of ENR with both PLA and lignin. The interfacial reaction was confirmed by Fourier transform infrared spectroscopy. The compatibility and interfacial adhesion between PLA and lignin were improved significantly by incorporation and increase in the content of ENR, as evidenced by the reduced interfacial gaps, blurry phase boundaries, and enhanced elastic response. As such, the mechanical properties of PLA/lignin composites were enhanced significantly. The tensile strength and elongation at break of PLA/lignin (W/W, 80/20) were improved by 15 % and 77 %, respectively, with the incorporation of only 1 wt% ENR. We believe this approach to compatibilize PLA/lignin composites is promising because it would not require costly modification of lignin and would not compromise the sustainability of composites.


Assuntos
Lignina , Borracha , Lignina/química , Borracha/química , Poliésteres/química , Resistência à Tração
17.
Int J Biol Macromol ; 244: 125202, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37270117

RESUMO

Cellulose nanocrystal (CNC) shows great potential in reinforced composites but it is difficult to disperse in epoxy thermosets due to its poor dispersity in epoxy monomers. Herein, we reported a novel approach to disperse CNC in epoxidized soybean oil (ESO)-derived epoxy thermosets uniformly by using the reversibility of dynamic imine-containing ESO-derived covalent adaptable network (CAN). The crosslinked CAN was deconstructed by an exchange reaction with ethylenediamine (EDA) in dimethyl formamide (DMF), leading to a solution of deconstructed CAN with plenty of hydroxyl and amino groups, which could form strong hydrogen bonds with hydroxyl groups of CNC and thus facilitated and stabilized dispersion of CNC in the deconstructed CAN solution. Epoxy composite with well-dispersed CNC was finally achieved by a reformation of CAN through the removal of DMF and EDA. In this way, the epoxy composites with CNC content up to 30 wt% were successfully prepared and showed drastically reinforced mechanical properties. The tensile strength and Young's modulus of the CAN were improved by up to ∼70 % and ∼45 times with the incorporation of 20 and 30 wt% CNC, respectively. The composites showed excellent reprocessability without significant loss in mechanical properties after reprocessing.


Assuntos
Celulose , Nanopartículas , Celulose/química , Resistência à Tração , Módulo de Elasticidade , Nanopartículas/química , Resinas Epóxi
18.
Cancers (Basel) ; 15(7)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37046624

RESUMO

The survival rate for pediatric cancers has remarkably improved in recent years. Conventional chemotherapy plays a crucial role in treating pediatric cancers, especially in low- and middle-income countries where access to advanced treatments may be limited. The Food and Drug Administration (FDA) approved chemotherapy drugs that can be used in children have expanded, but patients still face numerous side effects from the treatment. In addition, multidrug resistance (MDR) continues to pose a major challenge in improving the survival rates for a significant number of patients. This review focuses on the severe side effects of pediatric chemotherapy, including doxorubicin-induced cardiotoxicity (DIC) and vincristine-induced peripheral neuropathy (VIPN). We also delve into the mechanisms of MDR in chemotherapy to the improve survival and reduce the toxicity of treatment. Additionally, the review focuses on various drug transporters found in common types of pediatric tumors, which could offer different therapeutic options.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38133988

RESUMO

Point-voxel 3D object detectors have achieved impressive performance in complex traffic scenes. However, they utilize the 3D sparse convolution (spconv) layers with fixed receptive fields, such as voxel-based detectors, and inherit the fixed sphere radius from point-based methods for generating the features of keypoints, which make them weak in adaptively modeling various geometrical deformations and sizes of real objects. To tackle this issue, we propose a shape-adaptive set abstraction network (SASAN) for point-voxel 3D object detection. First, the proposal and offset generation module is adopted to learn the coordinates and confidences of 3D proposals and shape-adaptive offsets of the certain number of offset points for each voxel. Meanwhile, an extra offset supervision task is employed to guide the learning of shifting values of offset points, aiming at motivating the predicted offsets to preferably adapt to the various shapes of objects. Then, the shape-adaptive set abstraction module is proposed to extract multiscale keypoints features by grouping the neighboring offset points' features, as well as features learned from adjacent raw points and the 2-D bird-view map. Finally, the region of interest (RoI)-grid proposal refinement module is used to aggregate the keypoints features for further proposal refinement and confidence prediction. Extensive experiments on the competitive KITTI 3D detection benchmark demonstrate that the proposed SASAN gains superior performance as compared with state-of-the-art methods.

20.
Drugs Today (Barc) ; 59(2): 91-104, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36811409

RESUMO

Melanoma is a highly lethal type of skin cancer. Although an early diagnosis, in combination with surgery for nonmetastatic melanomas, significantly increases the probability of survival, there are no efficacious treatments for metastatic melanoma. Nivolumab and relatlimab are monoclonal antibodies that selectively interact with and block the proteins programmed cell death protein 1 (PD-1) and lymphocyte activation protein 3 (LAG-3), respectively, and thus, their activation by their cognate ligands. The combination of these immunotherapy drugs was approved in 2022 by the United States Food and Drug Administration (FDA) for the treatment of melanoma. Data from clinical trials indicated that, compared to nivolumab monotherapy, nivolumab and relatlimab produced more than a 2-fold median increase in progression-free survival (PFS) and a higher response rate in melanoma patients. This is an important finding as the response of patients to immunotherapies is limited due to dose-limiting toxicities and secondary drug resistance. This review article will discuss the pathogenesis of melanoma and the pharmacology of nivolumab and relatlimab. In addition, we will provide i) a summary of the anticancer drugs that inhibit LAG-3 and PD-1 in cancer patients and ii) our perspective about the use of nivolumab in combination with relatlimab to treat melanoma.


Assuntos
Melanoma , Nivolumabe , Humanos , Receptor de Morte Celular Programada 1 , Melanoma/tratamento farmacológico , Anticorpos Monoclonais Humanizados/uso terapêutico
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