Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
1.
Int J Biol Sci ; 20(7): 2640-2657, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38725843

RESUMO

Esophageal carcinoma is amongst the prevalent malignancies worldwide, characterized by unclear molecular classifications and varying clinical outcomes. The PI3K/AKT/mTOR signaling, one of the frequently perturbed dysregulated pathways in human malignancies, has instigated the development of various inhibitory agents targeting this pathway, but many ESCC patients exhibit intrinsic or adaptive resistance to these inhibitors. Here, we aim to explore the reasons for the insensitivity of ESCC patients to mTOR inhibitors. We assessed the sensitivity to rapamycin in various ESCC cell lines by determining their respective IC50 values and found that cells with a low level of HMGA1 were more tolerant to rapamycin. Subsequent experiments have supported this finding. Through a transcriptome sequencing, we identified a crucial downstream effector of HMGA1, FKBP12, and found that FKBP12 was necessary for HMGA1-induced cell sensitivity to rapamycin. HMGA1 interacted with ETS1, and facilitated the transcription of FKBP12. Finally, we validated this regulatory axis in in vivo experiments, where HMGA1 deficiency in transplanted tumors rendered them resistance to rapamycin. Therefore, we speculate that mTOR inhibitor therapy for individuals exhibiting a reduced level of HMGA1 or FKBP12 may not work. Conversely, individuals exhibiting an elevated level of HMGA1 or FKBP12 are more suitable candidates for mTOR inhibitor treatment.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Proteína HMGA1a , Inibidores de MTOR , Proteína Proto-Oncogênica c-ets-1 , Humanos , Linhagem Celular Tumoral , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/genética , Proteína Proto-Oncogênica c-ets-1/metabolismo , Proteína Proto-Oncogênica c-ets-1/genética , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Proteína HMGA1a/metabolismo , Proteína HMGA1a/genética , Inibidores de MTOR/farmacologia , Inibidores de MTOR/uso terapêutico , Proteína 1A de Ligação a Tacrolimo/metabolismo , Proteína 1A de Ligação a Tacrolimo/genética , Animais , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/tratamento farmacológico , Serina-Treonina Quinases TOR/metabolismo , Camundongos , Camundongos Nus
2.
Cell Death Dis ; 15(2): 158, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383528

RESUMO

Chemotherapy is a primary treatment for esophageal squamous cell carcinoma (ESCC). Resistance to chemotherapeutic drugs is an important hurdle to effective treatment. Understanding the mechanisms underlying chemotherapy resistance in ESCC is an unmet medical need to improve the survival of ESCC. Herein, we demonstrate that ferroptosis triggered by inhibiting high mobility group AT-hook 1 (HMGA1) may provide a novel opportunity to gain an effective therapeutic strategy against chemoresistance in ESCC. HMGA1 is upregulated in ESCC and works as a key driver for cisplatin (DDP) resistance in ESCC by repressing ferroptosis. Inhibition of HMGA1 enhances the sensitivity of ESCC to ferroptosis. With a transcriptome analysis and following-up assays, we demonstrated that HMGA1 upregulates the expression of solute carrier family 7 member 11 (SLC7A11), a key transporter maintaining intracellular glutathione homeostasis and inhibiting the accumulation of malondialdehyde (MDA), thereby suppressing cell ferroptosis. HMGA1 acts as a chromatin remodeling factor promoting the binding of activating transcription factor 4 (ATF4) to the promoter of SLC7A11, and hence enhancing the transcription of SLC7A11 and maintaining the redox balance. We characterized that the enhanced chemosensitivity of ESCC is primarily attributed to the increased susceptibility of ferroptosis resulting from the depletion of HMGA1. Moreover, we utilized syngeneic allograft tumor models and genetically engineered mice of HMGA1 to induce ESCC and validated that depletion of HMGA1 promotes ferroptosis and restores the sensitivity of ESCC to DDP, and hence enhances the therapeutic efficacy. Our finding uncovers a critical role of HMGA1 in the repression of ferroptosis and thus in the establishment of DDP resistance in ESCC, highlighting HMGA1-based rewiring strategies as potential approaches to overcome ESCC chemotherapy resistance. Schematic depicting that HMGA1 maintains intracellular redox homeostasis against ferroptosis by assisting ATF4 to activate SLC7A11 transcription, resulting in ESCC resistance to chemotherapy.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Ferroptose , Animais , Camundongos , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/genética , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Proteína HMGA1a/genética , Resistencia a Medicamentos Antineoplásicos/genética , Ferroptose/genética , Proteína HMGA1b , Linhagem Celular Tumoral
3.
Brain Res Bull ; 209: 110909, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38402994

RESUMO

BACKGROUND: The efficacy of acupuncture at Zusanli (ST36) in alleviating lower-limb pain is widely acknowledged in clinical practice, while its underlying mechanism remains incompletely elucidated. Our previous research had revealed that the prompt analgesia induced by needling-ST36 was accompanied by expression alterations in certain exco-nucleotidases within the sciatic nerve. Building upon this finding, the current work focused on NTPDase1, the primary ecto-nucleotidase in the human body, which converts ATP into AMP. METHODS: A 20-min acupuncture was administered unilaterally at the ST36 on rats with acute ankle arthritis. The pain thresholds of the injured hind paws were determined. Pharmacological interference was carried out by introducing the corresponding reagents to the sciatic nerve. ATP levels around the excised nerve were measured using a luciferase-luciferin assay. Live calcium imaging, utilizing the Fura 2-related-F340/F380 ratio, was conducted on Schwann cells in excised nerves and cultured rat SCs line, RSC96 cells. RESULTS: The analgesic effect induced by needling-ST36 was impaired when preventing ATP degradation via inhibiting NTPDase1 activities with ARL67156 or Ticlopidine. Conversely, increasing NTPDase1 activities with Apyrase duplicated the acupuncture effect. Similarly, preventing the conversion of AMP to adenosine via suppression of NT5E with AMP-CP hindered the acupuncture effect. Unexpectedly, impeded ATP hydrolysis ability and diminished NTPDase1 expression were observed in the treated group. Agonism at P2Y2Rs with ATP, UTP, or INS365 resulted in anti-nociception. Contrarily, antagonism at P2Y2Rs with Suramin or AR-C 118925xx prevented acupuncture analgesia. Immunofluorescent labeling demonstrated that the treated rats expressed more P2Y2Rs that were predominant in Schwann cells. Suppression of Schwann cells by inhibiting ErbB receptors also prevented acupuncture analgesia. Finally, living imaging on the excised nerves or RSC96 cells showed that agonism at P2Y2Rs indeed led to [Ca2+]i rise. CONCLUSION: These findings strongly suggest that the analgesic mechanism of needling-ST36 on the hypersensation in the lower limb partially relies on NTPDase1 activities in the sciatic nerve. In addition to facilitating adenosine signaling in conjunction with NT5E, most importantly, NTPDase1 may provide an appropriate low-level ATP milieu for the activation of P2Y2R in the sciatic nerve, particularly in Schwann cells.


Assuntos
Analgesia por Acupuntura , Terapia por Acupuntura , Antígenos CD , Artrite , Ratos , Humanos , Animais , Apirase , Tornozelo , Dor , Nervo Isquiático/metabolismo , Trifosfato de Adenosina/metabolismo , Analgésicos , Monofosfato de Adenosina , Adenosina , Pontos de Acupuntura
4.
Acta Pharmacol Sin ; 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195693

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common malignancy, presenting a formidable challenge to the medical community owing to its intricate pathogenic mechanisms. Although current prevention, surveillance, early detection, diagnosis, and treatment have achieved some success in preventing HCC and controlling overall disease mortality, the imperative to explore novel treatment modalities for HCC remains increasingly urgent. Epigenetic modification has emerged as pivotal factors in the etiology of cancer. Among these, RNA N6-methyladenosine (m6A) modification stands out as one of the most prevalent, abundant, and evolutionarily conserved post-transcriptional alterations in eukaryotes. The literature underscores that the dynamic and reversible nature of m6A modifications orchestrates the intricate regulation of gene expression, thereby exerting a profound influence on cell destinies. Increasing evidence has substantiated conspicuous fluctuations in m6A modification levels throughout the progression of HCC. The deliberate modulation of m6A modification levels through molecular biology and pharmacological interventions has been demonstrated to exert a discernible impact on the pathogenesis of HCC. In this review, we elucidate the multifaceted biological functions of m6A modifications in HCC, and concurrently advancing novel therapeutic strategies for the management of this malignancy.

5.
Front Biosci (Landmark Ed) ; 28(1): 1, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36722266

RESUMO

BACKGROUND: The activation of subcutaneous mast cells (MCs) helps to trigger the analgesic effect induced by acupuncture (AP), a traditional oriental therapy, that has been gradually accepted worldwide. This work aimed to reveal whether the serotonin (5-hydroxytryptamine, 5-HT) released from MCs plays an important role in this process, which has a controversial effect in the mechanism of pain. METHODS: In vivo tests, a 20-min session of AP was applied at Zusanli acupuncture point (acupoint) of acute ankle arthritis rats. Pain thresholds of the injured hindpaw were assessed to reflect the pain state, and the targeting substances in the interstitial space of the treated acupoint were sampled by microdialysis. In vitro experiments, exogenous 5-HT (exo-5-HT) was introduced to mediate adenosine triphosphate (ATP) release from cultured MCs. RESULTS: Needling promoted 5-HT accumulation at the Zusanli acupoint, which was prevented by sodium cromolyn. AP's analgesic effect was suppressed by the inhibition of 5-HT receptors at the acupoint, especially 5-HT1A subtype. In vitro tests, mechanical perturbation mimicking needling stimulation induced MCs to release 5-HT. 1 µM and 10 µM of exo-5-HT facilitated ATP release, which was restrained by blocking of 5-HT1 receptors rather than 5-HT3 receptors. As 5-HT, ATP and adenosine were also transiently accumulated in the treated acupoint during needling. Promoting ATP hydrolysis or activation adenosine A1 receptors duplicated AP analgesic effect. Finally, the inhibition of ATP receptors by suramin or pyridoxal phosphate-6-azo tetrasodium salt hydrate (PPADS) prevented AP analgesic effect. CONCLUSIONS: Our results suggest that MC-associated 5-HT release at acupoints contributes to AP analgesia, and the mediation of ATP secretion through 5-HT1A receptors might be the underlying mechanism at play. ATP could facilitate adenosine production or the propagation of needling signals.


Assuntos
Analgesia por Acupuntura , Artrite , Doença de Hashimoto , Animais , Ratos , Trifosfato de Adenosina , Serotonina , Pontos de Acupuntura , Mastócitos , Adenosina , Analgésicos
6.
Purinergic Signal ; 19(1): 69-85, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35113324

RESUMO

Our and in vitro studies had confirmed that mechanosensitive ATP release and accumulation in acupoints was elicited by acupuncture (AP), which might be a pivotal step for triggering AP analgesia. But to date, the dynamics of extracellular ATP (eATP) in the interstitial space during AP process was poorly known, mainly due to the low temporal resolution of the current detection approach. This study attempted to capture rapid eATP signals in vivo in the process of needling, and further explored the role of this eATP mobilization in initiating AP analgesic effect. Ipsilateral 20-min needling was applied on Zusanli acupoint (ST36) of complete Freund's adjuvant (CFA)-induced ankle arthritis rats. Pain thresholds were assessed in injured-side hindpaws. eATP in the interstitial space was microdialyzed and real-time quantified by luciferin-luciferase assay at 1-min interval with the aid of the microfluid chip. We revealed in behavioral tests that modulation of eATP levels in ST36 influenced AP analgesic effect on ankle arthritis. A transient eATP accumulation was induced by needling that started to mobilize at 4 min, climbed to the peak of 11.21 nM within 3.25 min and gradually recovered. Such AP-induced eATP mobilization was significantly impacted by ankle inflammation, needling depth, needle manipulation, and the presence of local ecto-nucleotidases. This work reveals that needling elicits a transient eATP mobilization in acupoints, which contributes to initiating AP analgesia. This study will help us better understand the peripheral mechanism of AP analgesia and guide clinicians to optimize the needle manipulations to improve AP efficacy.


Assuntos
Analgesia por Acupuntura , Terapia por Acupuntura , Artrite , Ratos , Animais , Pontos de Acupuntura , Analgésicos , Trifosfato de Adenosina
7.
J Cancer Prev ; 28(4): 175-184, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38205359

RESUMO

This study aimed to investigate the prognostic significance of tumor mutation burden (TMB) among patients with non-small cell lung cancer (NSCLC) who received platinum-based adjuvant chemotherapy. Tumor tissue specimens after surgical resection were collected for DNA extraction. Somatic mutation detection and TMB analysis were conducted using next-generation sequencing (NGS). Recurrence status of the patients was assessed in the hospital during the adjuvant chemotherapy period, and long-term survival data of patients were obtained by telephone follow-up. Univariate analysis between TMB status and prognosis was carried out by survival analysis. A retrospective review of 78 patients with non-squamous NSCLC who received platinum-based adjuvant chemotherapy showed a median disease-free survival of 3.6 years and median overall survival (OS) of 5.3 years. NGS analysis exhibited that the most common mutated somatic genes among the 78 patients were tumor suppressor protein p53 (TP53), epidermal growth factor receptor, low-density lipoprotein receptor related protein 1B, DNA methyltransferase 3 alpha and FAT atypical cadherin 3, and their prevalence was 56.4%, 48.7%, 37.2%, 30.7%, and 25.6%, respectively. TMB status was divided into TMB-L (≤ 4.5/Mb) and TMB-H (> 4.5/Mb) based on the median TMB threshold. Relevance of TMB to prognosis suggested that the median OS of patients with TMB-L was significantly longer than that of patients with TMB-H (NR vs. 4.6, P = 0.014). Higher TMB status conferred a worse implication on OS among patients with non-squamous NSCLC who received platinum-based adjuvant chemotherapy.

8.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(12): 1340-1344, 2022 Dec 15.
Artigo em Chinês | MEDLINE | ID: mdl-36544416

RESUMO

OBJECTIVES: To study the clinical and gastroscopic features of children with cyclic vomiting syndrome. METHODS: A retrospective analysis was performed on the medical data of 63 children with cyclic vomiting syndrome who were hospitalized and followed up in Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University from August 2019 to March 2022. RESULTS: Among the 63 children, there were 30 boys and 33 girls, with a mean age of 6.11 years, a mean course of disease of 2.57 years, and a mean vomiting period of 4.04 days. The most common accompanying symptom was listlessness or somnolence (55/63, 87%), followed by anorexia (45/63, 71%), abdominal pain or abdominal discomfort (40/63, 63%), constipation (19/63, 30%), salivation (12/63, 19%), nausea (11/63, 17%), headache (11/63, 17%), fever (6/63, 10%), and rash (1/63, 2%). All 63 children underwent gastroscopy, among whom 3 had no marked abnormalities, 22 (35%) had chronic superficial gastritis or chronic non-atrophic gastritis alone, and 38 (60%) had other abnormal changes aside from chronic gastritis (16 children with reflux esophagitis, 12 with bile reflux gastritis, 13 with duodenitis, 10 with erosive gastritis, and 5 with gastric or duodenal ulcer). Among the 63 children, 42 underwent pathological examinations of gastric mucosa, among whom 5 had no marked abnormalities, 34 had mild chronic gastritis, 2 had moderate chronic gastritis, and 1 had severe chronic gastritis. Among the 63 children, 15 received 24-hour dynamic esophageal pH monitoring during the interictal period, among whom 9 children were found to have pathological acid reflux. CONCLUSIONS: In addition to recurrent vomiting, most children with cyclic vomiting syndrome also have the symptoms such as somnolence or listlessness, anorexia, and abdominal pain. The main manifestation on gastroscopy is chronic gastritis, and most children may also have reflux esophagitis, bile reflux gastritis, and erosive gastritis. Mild chronic gastritis is the main pathological change of gastric mucosa.


Assuntos
Refluxo Biliar , Esofagite Péptica , Gastrite , Masculino , Feminino , Humanos , Criança , Gastroscopia , Esofagite Péptica/patologia , Refluxo Biliar/patologia , Anorexia/patologia , Estudos Retrospectivos , Sonolência , Gastrite/diagnóstico , Gastrite/patologia , Mucosa Gástrica/patologia , Vômito/etiologia , Vômito/patologia , Dor Abdominal
9.
J Nanobiotechnology ; 20(1): 235, 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35590324

RESUMO

BACKGROUND: MXenes with interesting optical and electrical properties have been attractive in biomedical applications such as antibacterial and anticancer agents, but their low photogeneration efficiency of reactive oxygen species (ROS) and poor stability are major concerns against microbial resistance. METHODS: Water-dispersible single layer Ti3C2Tx-based MXene through etching tightly stacked MAX phase precursor using a minimally intensive layer delamination method. After addition of Cu(II) ions, the adsorbed Cu(II) ions underwent self-redox reactions with the surface oxygenated moieties of MXene, leading to in situ formation of Cu2O species to yield Cu2O/Ti3C2Tx nanosheets (heterostructures). RESULTS: Under NIR irradiation, the Cu2O enhanced generation of electron-hole pairs, which boosted the photocatalytic production of superoxide and subsequent transformation into hydrogen peroxide. Broad-spectrum antimicrobial performance of Cu2O/Ti3C2Tx nanosheets with sharp edges is attributed to the direct contact-induced membrane disruption, localized photothermal therapy, and in situ generated cytotoxic free radicals. The minimum inhibitory concentration of Cu2O/Ti3C2Tx nanosheets reduced at least tenfold upon NIR laser irradiation compared to pristine Cu2O/Ti3C2Tx nanosheets. The Cu2O/Ti3C2Tx nanosheets were topically administrated on the methicillin-resistant Staphylococcus aureus (MRSA) infected wounds on diabetic mice. CONCLUSION: Upon NIR illumination, Cu2O/Ti3C2Tx nanosheets eradicated MRSA and their associated biofilm to promote wound healing. The Cu2O/Ti3C2Tx nanosheets with superior catalytic and photothermal properties have a great scope as an effective antimicrobial modality for the treatment of infected wounds.


Assuntos
Diabetes Mellitus Experimental , Staphylococcus aureus Resistente à Meticilina , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Camundongos , Oxirredução , Titânio/farmacologia
10.
Cells ; 11(5)2022 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-35269431

RESUMO

This review summarizes experimental evidence indicating that subcutaneous mast cells are involved in the trigger mechanism of analgesia induced by acupuncture, a traditional oriental therapy, which has gradually become accepted worldwide. The results are essentially based on work from our laboratories. Skin mast cells are present at a high density in acupuncture points where fine needles are inserted and manipulated during acupuncture intervention. Mast cells are sensitive to mechanical stimulation because they express multiple types of mechanosensitive channels, including TRPV1, TRPV2, TRPV4, receptors and chloride channels. Acupuncture manipulation generates force and torque that indirectly activate the mast cells via the collagen network. Subsequently, various mediators, for example, histamine, serotonin, adenosine triphosphate and adenosine, are released from activated mast cells to the interstitial space; they or their downstream products activate the corresponding receptors situated at local nerve terminals of sensory neurons in peripheral ganglia. The analgesic effects are thought to be generated via the reduced electrical activities of the primary sensory neurons. Alternatively, these neurons project such signals to pain-relevant regions in spinal cord and/or higher centers of the brain.


Assuntos
Pontos de Acupuntura , Analgesia , Humanos , Mastócitos , Dor , Células Receptoras Sensoriais
11.
Physiol Rep ; 9(21): e15099, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34755491

RESUMO

Our previous study indicated that streptozotocin (STZ)-induced diabetes leads to colonic platelet-derived growth factor receptor-α-positive (PDGFRα+ ) cell proliferation accompanied by slow colonic transit in mice; however, the mechanism of this effect is unclear. The present study used western blotting, immunohistochemistry, and quantitative PCR to investigate whether proteinase-activated receptor 2 (PAR2) mediates PDGFRα+ cell proliferation. Our results showed that PDGFRα, PAR2, and Ki-67 coexpression was increased in the diabetic colonic muscle layer. PDGFRα and PAR2 mRNA and protein expression levels were also markedly enhanced in the diabetic colonic muscle layer. Mice treated with 2-furoyl-LIGRLO-amide (2-F-L-a), a PAR2 agonist, exhibited significant colon elongation and increased smooth muscle weight. In the 2-F-L-a-treated mice, PDGFRα, PAR2, and Ki-67 coexpression was increased and PDGFRα and PAR2 mRNA and protein expression was significantly enhanced in the colonic smooth muscle layer. 2-F-L-a also increased proliferation and PDGFRα expression in NIH/3T3 cells cultured in high glucose, while LY294002, a PI3K antagonist, decreased cell proliferation and PDGFRα expression. PI3K and Akt protein and mRNA expression and p-Akt protein expression in diabetic and 2-F-L-a-treated mice were markedly reduced in colonic smooth muscle. 2-F-L-a also reduced PI3K, Akt, and p-Akt protein expression in NIH/3T3 cells, while the PI3K antagonist LY294002 increased this expression. The results indicate that PAR2 is involved in the proliferation of PDGFRα+ cells through the PI3K/Akt signaling pathway in the colon of STZ-induced diabetic mice, which may contribute to the slow transit and constipation that are associated with diabetes.


Assuntos
Proliferação de Células , Colo/metabolismo , Diabetes Mellitus Experimental/metabolismo , Receptor PAR-2/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Animais , Células Cultivadas , Colo/citologia , Colo/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/fisiologia , Células NIH 3T3 , Oligopeptídeos/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor PAR-2/agonistas , Receptor PAR-2/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Transdução de Sinais
12.
Nanoscale ; 11(12): 5580-5594, 2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-30860532

RESUMO

We have developed a rapid and straightforward topical treatment method for dry eye disease (DED) using poly(catechin) capped-gold nanoparticles (Au@Poly-CH NPs) carrying amfenac [AF; a nonsteroidal anti-inflammatory drug (NSAID)] through effective attenuation of ocular surface tissue damage in dry eyes. A dual-targeted strategy based on ocular therapeutics was adopted to simultaneously block the cyclooxygenase enzymes-induced inflammation and reactive oxygen species (ROS)-induced oxidative stress, the primary two causes of DED. The self-assembled core-shell Au@Poly-CH NPs synthesized via a simple reaction between tetrachloroaurate(iii) and catechin possess a poly(catechin) shell (∼20 nm) on the surface of each Au NP (∼60 nm). The anti-oxidant and anti-inflammatory properties of AF/Au@Poly-CH NPs were evaluated by DCFH-DA and prostaglandin E2/VEGF assays, respectively. Our results demonstrate that Au@Poly-CH NPs not only act as an anti-oxidant to suppress ROS-mediated processes, but also serve as a drug carrier of AF for a synergistic effect on anti-inflammation. In vivo biocompatibility studies show good tolerability of AF/Au@Poly-CH NPs for potential use in the treatment of ocular surface pathologies. The dual-targeted therapeutic effects of AF/Au@Poly-CH NPs lead to rapid recovery from DED in a rabbit model. Au@Poly-CH NPs loaded with NSAIDs is a promising multifunctional nanocomposite for treating various inflammation- and oxidative stress-related diseases.


Assuntos
Anti-Inflamatórios/química , Antioxidantes/química , Nanopartículas Metálicas/química , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Materiais Biocompatíveis/química , Catequina/química , Linhagem Celular , Córnea/citologia , Córnea/metabolismo , Córnea/patologia , Liberação Controlada de Fármacos , Síndromes do Olho Seco/tratamento farmacológico , Síndromes do Olho Seco/patologia , Ouro/química , Microscopia de Fluorescência , Mucina-5AC/metabolismo , Soluções Oftálmicas/química , Soluções Oftálmicas/farmacologia , Soluções Oftálmicas/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Fenilacetatos/química , Fenilacetatos/farmacologia , Fenilacetatos/uso terapêutico , Prostaglandina-Endoperóxido Sintases/química , Prostaglandina-Endoperóxido Sintases/metabolismo , Coelhos , Espécies Reativas de Oxigênio/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
13.
J Neurol ; 265(2): 362-369, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29249055

RESUMO

The aim of this report was to assess routine clinical brain magnetic resonance imaging (MRI) and its relation to clinical characteristics and disease prognosis. Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis patients were consecutively recruited from West China Hospital between October 1, 2011 and April 1, 2016. Brain MRI findings of 106 patients were analysed, and outcomes were assessed at 4, 8, and 12 months after discharge from the hospital using the modified Rankin scale (mRS). An MRI of the brain was normal in 52/106 (49.1%) patients and abnormal or atypical in 54/106 (50.9%) patients. The initial MRI was abnormal with T2 or fluid-attenuated inversion recovery (FLAIR) hyper-intensity signals in 20/106 (18.9%) patients. There were no statistically significant differences between the MRI findings and clinical presentations (seizure, hypoventilation, loss of consciousness, and tumour) (P > 0.05). Patients with normal MRIs were younger than patients with abnormal MRIs (P < 0.05). The mean mRS score at the 4-month follow-up was significantly higher in patients with abnormal MRIs than in patients with normal MRIs (P < 0.05). Brain MRI abnormalities are typically mild or unrelated to clinical symptoms, which is a clinico-radiological paradox of this type of immune encephalitis. Abnormal MRIs did not affect prognosis evaluated by mRS.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Adolescente , Adulto , Idoso , Encefalite Antirreceptor de N-Metil-D-Aspartato/patologia , Autoanticorpos , Criança , Estudos de Coortes , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Receptores de N-Metil-D-Aspartato/imunologia , Índice de Gravidade de Doença , Adulto Jovem
14.
Adv Healthc Mater ; 5(19): 2545-2554, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27448287

RESUMO

This study reports a two-step method to synthesize spermidine-capped fluorescent carbon quantum dots (Spd-CQDs) and their potential application as an antibacterial agent. Fluorescent carbon quantum dots (CQDs) are synthesized by pyrolysis of ammonium citrate in the solid state and then modified with spermidine by a simple heating treatment without a coupling agent. Spermidine, a naturally occurring polyamine, binds with DNA, lipids, and proteins involved in many important processes within organisms such as DNA stability, and cell growth, proliferation, and death. The antimicrobial activity of the as-synthesized Spd-CQDs (size ≈4.6 nm) has been tested against non-multidrug-resistant E. coli, S. aureus, B. subtilis, and P. aeruginosa bacteria and also multidrug-resistant bacteria, methicillin-resistant S. aureus (MRSA). The minimal inhibitory concentration value of Spd-CQDs is much lower (>25 000-fold) than that of spermidine, indicating their promising antibacterial characteristics. The mechanism of antibacterial activity is investigated, and the results indicate that Spd-CQDs cause significant damage to the bacterial membrane. In vitro cytotoxicity and hemolysis analyses reveal the high biocompatibility of Spd-CQDs. To demonstrate its practical application, in vitro MRSA-infected wound healing studies in rats have been conducted, which show faster healing, better epithelialization, and formation of collagen fibers when Spd-CQDs are used as a dressing material.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Carbono/química , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Pontos Quânticos/química , Espermidina/química , Espermidina/farmacologia , Células A549 , Animais , Ácido Cítrico/química , Células HEK293 , Células HeLa , Humanos , Células MCF-7 , Masculino , Testes de Sensibilidade Microbiana/métodos , Poliaminas/química , Compostos de Amônio Quaternário/química , Ratos , Ratos Sprague-Dawley
15.
ACS Appl Mater Interfaces ; 6(24): 21780-7, 2014 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-24730476

RESUMO

In this study, we developed a label-free, ultrasensitive graphene oxide (GO)-based probe for the detection of oligonucleotides by laser desorption/ionization mass spectrometry (LDI-MS). On the basis of simple π-π stacking and electrostatic interactions between rhodamine 6G (R6G) and GO, we prepared the nanocomposite R6G-modified GO (R6G-GO). Signal intensities of R6G increased in mass spectra in the presence of single-stranded oligonucleotides under pulsed laser irradiation (355 nm) of R6G-GO. In addition, the signal intensity of R6G was stronger in the presence of short oligonucleotides. Because small oligonucleotides improve the LDI efficiency of R6G on GO, we designed an enzyme-amplified signal transduction probe system for the detection of microRNA (miRNA). After specific digestion of the probe DNA (pDNA) strand from pDNA/miRNA-hybridized complexes by exonuclease III (Exo III), the resulting small oligonucleotide fragments increased the R6G signal during LDI-MS of R6G-GO. In addition, the signal intensity of the R6G ions increased with increasing concentrations of the target miRNA. Coupling this enzyme reaction and R6G-GO with LDI-MS enabled the detection of miRNA at concentrations of the femtomolar (fM) level. We also demonstrated the analysis of miRNA in tumor cells and utilized this R6G-GO probe in the detection of a single-nucleotide polymorphism (SNP) in the Arg249Ser unit of the TP53 gene. This simple, rapid, and sensitive detection system based on the coupling of functional GO with LDI-MS appears to have great potential as a tool for the bioanalyses of oligonucleotides and proteins.


Assuntos
Exodesoxirribonucleases/metabolismo , Grafite/metabolismo , MicroRNAs/análise , Neoplasias/genética , Linhagem Celular Tumoral , Humanos , Espectrometria de Massas , Microscopia Eletrônica de Transmissão , Neoplasias/patologia , Óxidos/metabolismo
16.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 2): m269-70, 2011 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-21522919

RESUMO

In the title coordinaltion polymer, [Cd(C(8)H(4)O(4))(C(8)H(7)N(3))(2)](n), the Cd(II) atom, lying on a twofold rotation axis, is six-coordinated by two carboxyl-ate O atoms from two benzene-1,3-dicarboxyl-ate (m-BDC) ligands and four N atoms from two chelating 2-(2-pyrid-yl)imidazole mol-ecules, forming a slightly distorted octa-hedral geometry. The m-BDC ligand is located over a twofold rotation axis. The Cd(II) atoms are bridged by the m-BDC ligands, leading to a wave-shaped chain structure along [010]. N-H⋯O hydrogen bonds connect the chains.

17.
Acta ortop. bras ; 19(4): 210-212, 2011. ilus
Artigo em Português | LILACS | ID: lil-601830

RESUMO

OBJETIVO: O cúbito varo é uma doença muito comum em crianças e adultos, ocasionada por fratura supracondilar. Existem vários procedimentos cirúrgicos e fixações internas para correção do cúbito varo, com diferentes desfechos, embora a fixação interna com placa e parafusos seja o mais comum. Contudo, o impacto do posicionamento da placa sobre a cirurgia raramente foi estudado até agora. MÉTODO: Em nosso estudo, 12 pacientes com cúbito varo foram divididos em dois grupos, operados pelo método de osteotomias em cunha com fechamento lateral e fixações internas com placa e parafusos. Em um grupo, as placas foram colocadas no lado póstero-lateral; no outro, as placas foram colocadas no lado lateral do úmero. RESULTADO: O período de acompanhamento foi 4,5 meses (faixa de 2 a 7 meses). Houve cinco resultados excelentes (83,3 por cento) e um bom (16,7 por cento) em cada grupo. Em todos os casos, a aparência é muito semelhante ao lado oposto; não há diferenças de amplitude de movimento (AM) no cotovelo depois da cirurgia. Um paciente no grupo B teve paralisia nervosa transitória; não houve infecções nem osteomielite. CONCLUSÃO: A posição da placa de fixação interna não tem impacto sobre a osteotomia em cunha de fechamento lateral. Nivel de Evidência II, Prospectivo Comparativo.


OBJECTIVE: To study the effects of low intensity ultrasound irradiation applied on the spinal cord, in the regeneration of the rat's sciatic nerve after a controlled crush injury, evaluating the functional results of the sciatic functional index as measured on video recorded images of the foot sole. METHODS: Eighteen rats were submitted to a controlled crush injury of the right sciatic nerve, and divided into two groups according to the treatment: Group 1 (n=9), simulated irradiation; Group 2 (n=9), effective irradiation. Low-intensity ultrasound irradiation was started on the 7th postoperative day and applied daily for 6 weeks. Images of the animals´ foot soles were video recorded on a transparenttreadmill belt at weekly intervals until the 6th week of irradiation, and the corresponding sciatic functional index (SFI) was measured usingspecific software. RESULTS: The SFI during the first and last week of treatment was -59.12 and -12.55 in Group 1, -53.31 and -1.32 in Group 2, indicating improvements of 79 percent and 97 percent, respectively, but differences between the groups were only significant (p<0.05) during the third week of treatment. CONCLUSION: The authors conclude that low intensity therapeutic ultrasound enhances nerve regeneration, with significance during the 3rd week of treatment. Level of Evidence: Level II, prospective comparative study.


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Cotovelo/cirurgia , Cotovelo/lesões , Fixação Interna de Fraturas/métodos , Osteotomia/métodos , Osteotomia/reabilitação , Fraturas da Ulna , Placas Ósseas , Parafusos Ósseos , Cotovelo
18.
Inorg Chem ; 46(3): 866-73, 2007 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-17257030

RESUMO

A series of new platinum(II) complexes containing both 4,4'-di-tert-butyl-2,2'-bipyridine (dbbpy) and the extended tetrathiafulvalenedithiolate ligands have been prepared and characterized. These complexes include [Pt(dbbpy)(C8H4S8)] (1; C8H4S82- = 2-{(4,5-ethylenedithio)-1,3-dithiol-2-ylidene}-1,3-dithiol-4,5-dithiolate), [Pt(dbbpy)(ptdt)] (2; ptdt = 2-{(4,5-cyclopentodithio)-1,3-dithiol-2-ylidene}-1,3-dithiol-4,5-dithiolate), [Pt(dbbpy)(mtdt)] (3; mtdt = 2-{(4,5-methylethylenedithio)-1,3-dithiol-2-ylidene}-1,3-dithiol-4,5-dithiolate), [Pt(dbbpy)(btdt)] (4; btdt = benzotetrathiafulvalenedithiolate), [Pt(dbbpy)(C8H6S8)] (5; C8H6S82- = 2-{4,5-bis(methylthio)-1,3-dithiol-2-ylidene}-1,3-dithiol-4,5-dithiolate), [Pt(dbbpy)(3O-C6S8)] (6; 3O-C6S82- = 2-{4,5-dithia-(3',6',9'-trioxaundecyl)-1,3-dithiol-2-ylidene}-1,3-dithiol-4,5-dithiolate), and [Pt(dbbpy)(4O-C6S8)] (7; 4O-C6S82- = 2-{4,5-dithia-(3',6',9',12'-tetraoxatetradecyl)-1,3-dithiol-2-ylidene}-1,3-dithiol-4,5-dithiolate). The crystal structures of a new ligand precursor (2-[4,5-dithia-(3',6',9',12'-tetraoxatetradecyl)-1,3-dithiol-2-ylidene]-4,5-bis(2-cyanoethylsulfanyl)-1,3-dithiole, IIIc) and complexes 5-7 have been determined by X-ray crystallography. Complexes 1-7 show intense electronic absorption bands in the UV-vis region due to the intramolecular mixed metal/ligand-to-ligand charge-transfer transition, and they display significant solvatochromic behavior. Redox properties of these compounds have been investigated by cyclic voltammetry, and complex 7 shows a significant response for Na+ ions with a large positive shift of ca. 45 mV.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA