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1.
Angew Chem Int Ed Engl ; : e202409793, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38923266

RESUMEN

Due to the challenge of cleaving O-O bonds at single Co sites, mononuclear Co complexes typically show poor selectivity for the four-electron (4e-) oxygen reduction reaction (ORR). Herein, we report on selective 4e- ORR catalyzed by a Co porphyrin with a hanged ZnII ion. Inspired by Cu/Zn-superoxide dismutase, we designed and synthesized 1-CoZn with a hanging ZnII at the second sphere of a Co porphyrin. Complex 1-CoZn is much more effective than its Zn-lacking analogues to catalyze the 4e- ORR in neutral aqueous solutions, giving an electron number of 3.91 per O2 reduction. With spectroscopic studies, the hanging ZnII was demonstrated to be able to facilitate the electron transfer from CoII to O2, through an electronic "pull effect", to give CoIII-superoxo. Theoretical studies further suggested that this "pull effect" plays crucial roles in assisting O-O bond cleavage. This work is significant to present a new strategy of hanging a ZnII to improve O2 activation and O-O bond cleavage.

2.
J Neuroendocrinol ; 36(4): e13381, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38468159

RESUMEN

Hematological indicators of chronic systemic inflammation are significant biomarkers for gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs). We performed a systematic review and meta-analysis to assess the impact of certain factors on the overall survival (OS), progression-free survival (PFS), and disease-free survival (DFS) of patients with GEP-NENs. These factors include the neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), lymphocyte/monocyte ratio (LMR), and C-reactive protein (CRP) levels. After searching the Medline, Embase, and Cochrane Library databases from January 1, 2000 to October 20, 2022 and the American Society of Clinical Oncology conference proceedings from January 1, 2017, hazard ratios (HRs) and 95% confidence intervals (CIs) were extracted. Subgroup analyses were conducted to identify the origins of heterogeneity and examine the impact of factor grouping. The effects of the cut-off values and sample size were assessed by meta-regression. The results revealed that higher NLRs, PLRs, and CRP levels were associated with shorter OS (HR = 2.09, 95% CI = 1.55-2.8; HR = 1.79, 95% CI = 1.40-2.28; and HR = 2.88, 95% CI = 2.09-3.95, respectively; all p < 0.001). Higher NLRs and lower LMRs were associated with shorter DFS (HR = 3.34, 95% CI = 2.11-5.29 and HR = 2.71, 95% CI = 2.27-3.24, respectively; both p < 0.001). Higher PLRs and CRP levels were correlated with shorter PFS (HR = 3.48, 95% CI = 1.34-9.03, p = 0.01 and HR = 3.14, 95% CI = 1.63-6.08, p = 0.001). As demonstrated in the research, hematological indicators of systemic inflammation are promising biomarkers for GEP-NEN assessment.


Asunto(s)
Linfocitos , Tumores Neuroendocrinos , Humanos , Pronóstico , Biomarcadores/metabolismo , Linfocitos/metabolismo , Inflamación/metabolismo , Tumores Neuroendocrinos/diagnóstico , Tumores Neuroendocrinos/metabolismo
3.
J Integr Plant Biol ; 66(2): 166-168, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38294100

RESUMEN

The Ti-TAN TurboID plasmid toolbox enables proximity labeling applications in transient assays in Nicotiana benthamiana in a fast and cost-efficient manner, making TurboID-based proximity labeling broadly accessible to plant scientists.


Asunto(s)
Nicotiana , Titanio , Nicotiana/genética , Plantas , Plásmidos/genética
4.
Angew Chem Int Ed Engl ; 63(7): e202313034, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38097503

RESUMEN

Oxygen reduction reaction (ORR) is of critical significance in the advancement of fuel cells and zinc-air batteries. The iron-nitrogen (Fe-Nx ) sites exhibited exceptional reactivity towards ORR. However, the task of designing and controlling the local structure of Fe species for high ORR activity and stability remains a challenge. Herein, we have achieved successful immobilization of Fe species onto the highly curved surface of S, N co-doped carbonaceous nanosprings (denoted as FeNS/Fe3 C@CNS). The induction of this twisted configuration within FeNS/Fe3 C@CNS arose from the assembly of chiral templates. For electrocatalytic ORR tests, FeNS/Fe3 C@CNS exhibits a half-wave potential (E1/2 ) of 0.91 V in alkaline medium and a E1/2 of 0.78 V in acidic medium. The Fe single atoms and Fe3 C nanoparticles are coexistent and play as active centers within FeNS/Fe3 C@CNS. The highly curved surface, coupled with S substitution in the coordination layer, served to reduce the energy barrier for ORR, thereby enhancing the intrinsic catalytic activity of the Fe single-atom sites. We also assembled a wearable flexible Zn-air battery using FeNS/Fe3 C@CNS as electrocatalysts. This work provides new insights into the construction of highly curved surfaces within carbon materials, offering high electrocatalytic efficacy and remarkable performance for flexible energy conversion devices.

5.
BMC Gastroenterol ; 23(1): 440, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38097952

RESUMEN

BACKGROUND: Type 1 gastric neuroendocrine tumors (NETs) are relatively rare to the extent that some physicians have little experience in diagnosing and treating them. The purpose of this study was to increase the understanding of the disease by analyzing and summarizing the management and prognoses of patients with type 1 gastric NETs at our center. METHODS: The data of 229 patients (59.4% female) with type 1 gastric NETs who were treated at our center during 2011-2022 were retrospectively analyzed. RESULTS: The average patient age was 50.5 ± 10.8 years. Multiple tumors affected 72.5% of the patients; 66.4% of the tumors were < 1 cm, 69.4% were NET G1, and 2.2% were stage III-IV. A total of 76.9% of the patients had received endoscopic management, 60.7% had received traditional Chinese medicine treatment, 10.5% received somatostatin analogues treatment, and 6.6% underwent surgical resection. Seventy patients (41.2%) experienced the first recurrence after a median follow-up of 31 months (range: 2-122 months), and the median recurrence-free time was 43 months. The 1-, 2-, and 3-year cumulative recurrence-free survival rates were 71.8%, 56.8%, and 50.3%, respectively. During a median follow-up of 39 months (range: 2-132 months), one patient had bilateral pulmonary metastasis, and no disease-related deaths were observed. CONCLUSION: Type 1 gastric NETs have a high recurrence rate and a long disease course, underscoring the importance of long-term and comprehensive management.


Asunto(s)
Tumores Neuroendocrinos , Neoplasias Gástricas , Humanos , Femenino , Adulto , Persona de Mediana Edad , Masculino , Tumores Neuroendocrinos/diagnóstico , Tumores Neuroendocrinos/terapia , Tumores Neuroendocrinos/patología , Estudios Retrospectivos , Pronóstico , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/terapia
6.
Zhongguo Gu Shang ; 36(9): 859-65, 2023 Sep 25.
Artículo en Chino | MEDLINE | ID: mdl-37735079

RESUMEN

OBJECTIVE: To investigate the clinical effect of "Tianji" orthopedic robot-assisted percutaneous vertebro plasty(PVP) surgery in the treatment of upper thoracic osteoporotic fracture. METHODS: A retrospective analysis was performed on 32 patients with upper thoracic osteoporotic fracture who underwent PVP surgery in Shenzhen Hospital of Traditional Chinese Medicine from August 2016 to June 2022. There were 8 males and 24 females, ranging in age from 58 to 90 years old, with a mean of (67.75±12.27) years old. Fifteen patients were treated with robot-assisted PVP surgery (robot group), including 3 males and 12 females, with an average age of (68.5±10.3) years. Fracture location:1 case of T2 fracture, 1 case of T3 fracture, 3 cases of T4 fracture, 3 cases of T5 fracture, and 7 cases of T6 fracture. The follow-up period ranged from 1.0 to 3.0 months, with a mean of (1.6±0.7) months. Seventeen patients underwent routine PVP surgery (conventional group), including 5 males and 12 females, with an average age of (66.8±11.6) years old. Fracture location:1 case of T1 fracture, 5 cases of T4 fracture, 2 cases of T5 fracture and 9 cases of T6 fracture. The follow-up period ranged from 0.5 to 4.0 months, with a mean of (1.5±0.6) months. Preoperative and postoperative visual analogue scale(VAS) and Oswestry disability index(ODI) scores were compared between the two groups, and the number of punctures, perspective times, operation time, intraoperative blood loss, bone cement distribution, bone cement leakage, and intraoperative radiation dose were compared between the two groups. RESULTS: Number of punctures times, perspective times, operation time, intraoperative blood loss, bone cement distribution, bone cement leakage and intraoperative radiation dose in the robot group were all significantly better than those in the conventional group(P<0.05). VAS of 2.03±0.05 and ODI of (22.16±4.03) % in the robot group were significantly better than those of the robot group before surgery, which were (8.67±0.25) score and (79.40±7.72)%(t=100.869, P<0.001;t=25.456, P<0.001). VAS of 2.17±0.13 and ODI of (23.88±6.15)% in the conventional group were significantly better than those before surgery, which were (8.73±0.18) score and (80.01±7.59)%(t=121.816, P<0.001;t=23.691, P<0.001). There was no significant difference in VAS and ODI between the two groups after operation (t=-3.917, P=0.476;t=-0.922, P=0.364). CONCLUSION: Robot-assisted PVP in the treatment of upper thoracic osteoporotic fractures can further improve surgical safety, reduce bone cement leakage, and achieve satisfactory clinical efficacy.


Asunto(s)
Fracturas Osteoporóticas , Robótica , Femenino , Masculino , Humanos , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Fracturas Osteoporóticas/cirugía , Pérdida de Sangre Quirúrgica , Cementos para Huesos , Estudios Retrospectivos , Vértebras Torácicas/cirugía
7.
Adv Mater ; 35(42): e2305659, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37620729

RESUMEN

Oxygen evolution reaction (OER) plays a key role in proton exchange membrane water electrolysis (PEMWE), yet the electrocatalysts still suffer from the disadvantages of low activity and poor stability in acidic conditions. Here, a new class of CdRu2 IrOx nanoframes with distorted structure for acidic OER is successfully fabricated. Impressively, CdRu2 IrOx displays an ultralow overpotential of 189 mV and an ultralong stability of 1500 h at 10 mA cm⁻2 toward OER in 0.5 M H2 SO4 . Moreover, a PEMWE using the distorted CdRu2 IrOx can be steadily operated at 0.1 A cm⁻2 for 90 h. Microstructural analyses and X-ray absorption spectroscopy (XAS) demonstrate that the synergy between Ru and Ir in CdRu2 IrOx induces the distortion of Ru-O, Ir-O, and Ru-M (M = Ru, Ir) bonds. In situ XAS indicates that the applied potential leads to the deformation octahedral structure of RuOx /IrOx and the formation of stable Ru5+ species for OER. Theoretical calculations also reveal that the distorted structures can reduce the energy barrier of rate-limiting step during OER. This work provides an efficient strategy for constructing structural distortion to achieve significant enhancement on the activity and stability of OER catalysts.

8.
Nanomaterials (Basel) ; 13(7)2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-37049334

RESUMEN

Exploiting cost-effective and durable non-platinum electrocatalysts for oxygen reduction reaction (ORR) is of great significance for the development of abundant renewable energy conversion and storage technologies. Herein, a series of Co3O4 supported on graphene-like carbon (Co3O4/C) samples were firstly effectively synthesized by one-step calcination of cobalt phthalocyanine and their electrocatalytic performances were measured for ORR under an alkaline medium. By systematically adjusting the calcination temperature of cobalt phthalocyanine, we found that the material pyrolyzed at 750 °C (Co3O4/C-750) shows the best ORR electrocatalytic performance (half-wave potentials of 0.77 V (vs. RHE) in 0.1 M KOH) among all the control samples. Moreover, it displays better stability and superior methanol tolerance than commercial 20% Pt/C. The further electrochemical test results reveal that the process is close in characteristics to the four-electron ORR process on Co3O4/C-750. In addition, Co3O4/C-750 applied in the zinc-air battery presents 1.34 V of open circuit potential. Based on all the characterizations, the enhanced electrocatalytic performances of Co3O4/C-750 composite should be ascribed to the synergistic effect between Co3O4 and the graphene-like carbon layer structure produced by pyrolysis of cobalt phthalocyanine, as well as its high specific surface area.

9.
PLoS Pathog ; 18(10): e1010909, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36256684

RESUMEN

Viruses manipulate the cells they infect in order to replicate and spread. Due to strict size restrictions, viral genomes have reduced genetic space; how the action of the limited number of viral proteins results in the cell reprogramming observed during the infection is a long-standing question. Here, we explore the hypothesis that combinatorial interactions may expand the functional landscape of the viral proteome. We show that the proteins encoded by a plant-infecting DNA virus, the geminivirus tomato yellow leaf curl virus (TYLCV), physically associate with one another in an intricate network, as detected by a number of protein-protein interaction techniques. Importantly, our results indicate that intra-viral protein-protein interactions can modify the subcellular localization of the proteins involved. Using one particular pairwise interaction, that between the virus-encoded C2 and CP proteins, as proof-of-concept, we demonstrate that the combination of viral proteins leads to novel transcriptional effects on the host cell. Taken together, our results underscore the importance of studying viral protein function in the context of the infection. We propose a model in which viral proteins might have evolved to extensively interact with other elements within the viral proteome, enlarging the potential functional landscape available to the pathogen.


Asunto(s)
Begomovirus , Virus de Plantas , Solanum lycopersicum , Proteínas Virales/genética , Proteínas Virales/metabolismo , Proteoma/metabolismo , Enfermedades de las Plantas , Begomovirus/metabolismo , Virus de Plantas/metabolismo
10.
World J Gastroenterol ; 28(20): 2163-2175, 2022 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-35721885

RESUMEN

Pancreatic neuroendocrine neoplasms (PanNENs) are rare neoplasms with strong heterogeneity that have experienced an increasing incidence rate in recent years. For patients with locally advanced or distant metastatic PanNENs, systemic treatment options vary due to the different differentiations, grades and stages. The available options for systemic therapy include somatostatin analogs, mole-cularly targeted agents, cytotoxic chemotherapeutic agents, immune checkpoint inhibitors, and peptide receptor radionuclide therapy. In addition, the development of novel molecularly targeted agents is currently in progress. The sequence of selection between different chemotherapy regimens has been of great interest, and resistance to chemotherapeutic agents is the major limitation in their clinical application. Novel agents and high-level clinical evidence continue to emerge in the field of antiangiogenic agents. Peptide receptor radionuclide therapy is increasingly employed for the treatment of advanced neuroendocrine tumors, and greater therapeutic efficacy may be achieved by emerging radio-labeled peptides. Since immune checkpoint inhibitor monotherapies for PanNENs appear to have limited antitumor activity, dual immune checkpoint inhibitor therapies or combinations of antiangiogenic therapies and immune checkpoint inhibitors have been applied in the clinic to improve clinical efficacy. Combining the use of a variety of agents with different mechanisms of action provides new possibilities for clinical treatments. In the future, the study of systemic therapies will continue to focus on the screening of the optimal benefit population and the selection of the best treatment sequence strategy with the aim of truly achieving individualized precise treatment of PanNENs.


Asunto(s)
Antineoplásicos , Tumores Neuroendocrinos , Neoplasias Pancreáticas , Inhibidores de la Angiogénesis/uso terapéutico , Antineoplásicos/uso terapéutico , Humanos , Inhibidores de Puntos de Control Inmunológico , Tumores Neuroendocrinos/tratamiento farmacológico , Tumores Neuroendocrinos/patología , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/patología , Radioisótopos/uso terapéutico , Receptores de Péptidos , Somatostatina
11.
Methods Mol Biol ; 2382: 115-127, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34705236

RESUMEN

The availability of a fast and controlled mitotic model system that could simplify the generation of genetic material and reduce the experimental time from months to days would largely benefit research in plant cell division. In this protocol, we propose the use of pavement cells of Nicotiana benthamiana leaves to study cell division, which is artificially induced by Agrobacterium-mediated transient overexpression of the transcription factor E2Fb. The cell division-inducing overexpression of E2Fb can be combined with the expression of fluorescent protein-tagged proteins of interest or with dyes, which could be visualized throughout the cell cycle under the microscope. This simple and affordable method enables the study of cell cycle regulation and cell division in plants, from genome replication to cell wall formation, in a fast and controlled manner, and can be used for functional studies when coupled with chemical inhibitors or reverse genetic approaches.


Asunto(s)
Nicotiana , Agrobacterium/genética , Agrobacterium tumefaciens/genética , División Celular , Factores de Transcripción E2F , Hojas de la Planta/genética , Plantas Modificadas Genéticamente/genética , Nicotiana/genética
12.
World J Clin Cases ; 9(24): 7146-7153, 2021 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-34540971

RESUMEN

BACKGROUND: Neuroendocrine carcinoma of the breast (NECB) is a rare type of malignant tumor. Due to the rarity of NECB, the relevant literature mostly comprises case reports. Available data on treatment options for NECB are very limited. CASE SUMMARY: A 62-year-old woman presented to our hospital in October 2016 for intermittent vomiting and diarrhea and masses in the liver found on abdominal computed tomography (CT) imaging. She was diagnosed in July 2012 with neuroendocrine carcinoma of the right breast in local hospital. The patient initially presented with a painful lesion of the right breast. She then undergone surgical resection and adjuvant chemotherapy with pirarubicin and paclitaxel for four cycles as well as endocrine therapy. She was regularly followed every 3 mo after surgery. Enhanced abdominal CT imaging at our hospital revealed multiple suspicious masses in the liver with the largest lesion measuring 8.4 cm × 6.3 cm. Chest CT revealed masses in the anterior chest wall and lung. Core needle biopsy of the lesion revealed liver metastases of NECB. A bone scan showed right second anterior rib metastases. Upper endoscopy and colonoscopy did not provide any evidence of another possible primary tumor. She stopped receiving endocrine therapy and then received etoposide and cisplatin (EP) chemotherapy as a first-line treatment regimen for six cycles at our hospital after liver, bone, and lung metastases. On October 2017, the chemotherapy regimen was changed to S-1 (40 mg twice daily, days 1-14) combined with temozolomide (200 mg once daily, days 10-14) (STEM) every 21 d as a second-line treatment regimen due to disease progression. Progression-free survival (PFS) and adverse effects after treatment were analyzed, and the efficacy of the STEM regimen was assessed using RECIST version 1.1. This patient achieved a partial response after using the STEM regimen, with a PFS of 23 mo. Adverse effects included only grade 1 digestive tract reactions with no need for a reduction in chemotherapy. CONCLUSION: This case report suggests that the STEM regimen may be effective and well tolerated as the second-line treatment for advanced NECB. STEM is still highly effective in patients who show disease progression with the EP regimen. More evidence is needed to prove the validity of STEM.

13.
Nat Commun ; 12(1): 4278, 2021 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-34257307

RESUMEN

Geminiviruses are plant viruses with limited coding capacity. Geminivirus-encoded proteins are traditionally identified by applying a 10-kDa arbitrary threshold; however, it is increasingly clear that small proteins play relevant roles in biological systems, which calls for the reconsideration of this criterion. Here, we show that geminiviral genomes contain additional ORFs. Using tomato yellow leaf curl virus, we demonstrate that some of these small ORFs are expressed during the infection, and that the encoded proteins display specific subcellular localizations. We prove that the largest of these additional ORFs, which we name V3, is required for full viral infection, and that the V3 protein localizes in the Golgi apparatus and functions as an RNA silencing suppressor. These results imply that the repertoire of geminiviral proteins can be expanded, and that getting a comprehensive overview of the molecular plant-geminivirus interactions will require the detailed study of small ORFs so far neglected.


Asunto(s)
Begomovirus/patogenicidad , Geminiviridae/genética , Geminiviridae/patogenicidad , Genoma Viral/genética , Interacciones Huésped-Patógeno/genética , Interacciones Huésped-Patógeno/fisiología , Sistemas de Lectura Abierta/genética , Enfermedades de las Plantas/virología , Interferencia de ARN/fisiología , Nicotiana/ultraestructura , Proteínas Virales/genética , Proteínas Virales/metabolismo , Virulencia
14.
World J Gastroenterol ; 27(21): 2895-2909, 2021 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-34135560

RESUMEN

BACKGROUND: Poorly differentiated gastric neuroendocrine neoplasms (PDGNENs) include gastric neuroendocrine carcinoma (NEC) and mixed adenoneuroendocrine carcinoma, which are highly malignant and rare tumors, and their incidence has increased over the past few decades. However, the clinicopathological features and outcomes of patients with PDGNENs have not been completely elucidated. AIM: To investigate the clinicopathological characteristics and prognostic factors of patients with PDGNENs. METHODS: The data from seven centers in China from March 2007 to November 2019 were analyzed retrospectively. RESULTS: Among the 232 patients with PDGNENs, 191 (82.3%) were male, with an average age of 62.83 ± 9.11 years. One hundred and thirteen (49.34%) of 229 patients had a stage III disease and 86 (37.55%) had stage IV disease. Three (1.58%) of 190 patients had no clinical symptoms, while 187 (98.42%) patients presented clinical symptoms. The tumors were mainly (89.17%) solitary and located in the upper third of the stomach (cardia and fundus of stomach: 115/215, 53.49%). Most lesions were ulcers (157/232, 67.67%), with an average diameter of 4.66 ± 2.77 cm. In terms of tumor invasion, the majority of tumors invaded the serosa (116/198, 58.58%). The median survival time of the 232 patients was 13.50 mo (7, 31 mo), and the overall 1-year, 3-year, and 5-year survival rates were 49%, 19%, and 5%, respectively. According to univariate analysis, tumor number, tumor diameter, gastric invasion status, American Joint Committee on Cancer (AJCC) stage, and distant metastasis status were prognostic factors for patients with PDGNENs. Multivariate analysis showed that tumor number, tumor diameter, AJCC stage, and distant metastasis status were independent prognostic factors for patients with PDGNENs. CONCLUSION: The overall prognosis of patients with PDGNENs is poor. The outcomes of patients with a tumor diameter > 5 cm, multiple tumors, and stage IV tumors are worse than those of other patients.


Asunto(s)
Tumores Neuroendocrinos , Neoplasias Gástricas , Anciano , China/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Tumores Neuroendocrinos/patología , Pronóstico , Estudios Retrospectivos , Neoplasias Gástricas/epidemiología , Neoplasias Gástricas/patología
15.
Nat Commun ; 12(1): 2780, 2021 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-33986276

RESUMEN

Geminiviruses are causal agents of devastating diseases in crops. Geminiviruses have circular single-stranded (ss) DNA genomes that are replicated in the nucleus of the infected plant cell through double-stranded (ds) DNA intermediates by the plant DNA replication machinery. Which host DNA polymerase mediates geminiviral multiplication, however, has so far remained elusive. Here, we show that subunits of the nuclear replicative DNA polymerases α and δ physically interact with the geminivirus-encoded replication enhancer protein, C3, and that these polymerases are required for viral replication. Our results suggest that, while DNA polymerase α is essential to generate the viral dsDNA intermediate, DNA polymerase δ mediates the synthesis of new copies of the geminiviral ssDNA genome, and that the virus-encoded C3 may act selectively, recruiting DNA polymerase δ over ε to favour productive replication.


Asunto(s)
ADN Polimerasa III/metabolismo , ADN Polimerasa I/metabolismo , Replicación del ADN/genética , ADN Viral/biosíntesis , Geminiviridae/genética , Replicación Viral/genética , Genoma Viral/genética , Plantas/virología , Subunidades de Proteína/metabolismo , Proteínas Virales/metabolismo
16.
BMC Gastroenterol ; 21(1): 188, 2021 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-33892648

RESUMEN

BACKGROUND: Currently, there are no circulating diagnostic biomarkers for gastric neuroendocrine neoplasms (g-NENs). In previous studies, we found that miRNA-202-3p is overexpressed in the tumour tissue of type 1 g-NEN. We speculated that miRNA-202-3p is also likely to be highly expressed in circulating blood. METHODS: A total of 27 patients with type 1 g-NEN and 27 age- and sex-matched control participants were enrolled in this study. The miRNA-202-3p levels in serum obtained from the participants were measured by qRT-PCR. The expression level of miRNA-202-3p in the samples was calculated by comparison with a standard curve. RESULTS: The clinical characteristics of the patients were similar to those of the patient samples in previous reports. Expression of miRNA-202-3p was significantly higher in the patient group (3.84 × 107 copies/nl) than in the control group (0.635 × 107 copies/nl). The area under the ROC curve (AUC) was 0.878 (95% CI: 0.788-0.968), and the optimal cut-off point was approximately 1.12 × 107 copies/nl. The sensitivity and specificity were 88.9% and 77.8%, respectively. CONCLUSION: This study suggests that miRNA-202-3p is potentially useful as a biomarker of type 1 g-NEN; further investigation and verification should be performed in future research.


Asunto(s)
MicroARNs/sangre , Tumores Neuroendocrinos , Neoplasias Gástricas , Biomarcadores , Biomarcadores de Tumor/genética , Perfilación de la Expresión Génica , Humanos , Tumores Neuroendocrinos/diagnóstico , Tumores Neuroendocrinos/genética , Curva ROC , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética
17.
Neuroendocrinology ; 111(8): 752-763, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32668427

RESUMEN

OBJECTIVE: The efficacy of the capecitabine/temozolomide (CAPTEM) regimen has been demonstrated in metastatic neuroendocrine neoplasms (NENs), but because of varying response rates among the patients, biomarkers to predict its response are greatly needed. Here, we investigated the clinical utility of a Ki-67 index to predict the CAPTEM regimen objective responses and select patients who could benefit from this regimen. METHODS: Metastatic NENs patients treated with the CAPTEM regimen from 4 high-volume medical centers were selected and grouped in a training and validation cohort. The classification and regression tree (CART) was generated to identify the optimal threshold of Ki-67 for stratifying the patients into different Ki-67 range groups based on their response to the CAPTEM regimen. RESULTS AND CONCLUSIONS: The overall response rate (ORR) and disease control rate of the entire cohort (N = 151) were 26.5 and 76.2%, respectively, with a median progression-free survival (PFS) of 12.0 months. CART analysis showed that patients in the Ki-67 range group 10-40% demonstrated a significantly higher ORR than those in Ki-67 >40 and <10% groups (p < 0.001 in the training cohort and p = 0.036 in the validation cohort). Response to the CAPTEM regimen was not influenced by the expression of O6-methylguanine-DNA methyltransferase or primary tumor location. Multivariate analysis identified the Ki-67 index as the only independent prognostic factor for overall survival (p = 0.031) and PFS (p = 0.006). The proposed Ki-67 index was externally validated and could be used to clinically identify suitable metastatic NENs patients who could achieve an optimal cytoreduction using the CAPTEM regimen.


Asunto(s)
Antineoplásicos/farmacología , Capecitabina/farmacología , Antígeno Ki-67/sangre , Tumores Neuroendocrinos/tratamiento farmacológico , Evaluación de Resultado en la Atención de Salud , Temozolomida/farmacología , Adolescente , Adulto , Anciano , Quimioterapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/sangre , Pronóstico , Estudios Retrospectivos , Adulto Joven
18.
World J Gastrointest Oncol ; 12(12): 1416-1427, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-33362912

RESUMEN

BACKGROUND: For the rarity of type 3 gastric neuroendocrine tumours (g-NETs), their clinicopathological characteristics and prognosis are not well illustrated. AIM: To describe the clinicopathological features and outcome of type 3 g-NETs in the Chinese population. METHODS: Based on the 2019 WHO pathological classification, the clinicopathological characteristics and prognosis of patients with type 3 g-NETs in China were retrospectively analysed. RESULTS: A total of 77 patients (55.8% of females) with type 3 g-NETs were analysed, with a median age of 48 years (range: 28-79 years). The tumours were mainly located in the gastric fundus/body (83.1%) and were mostly solitary (83.1%), with a median size of 1.5 cm (0.8-3.5 cm). Of these, there were 37 G1 tumours (48.1%), 31 G2 (40.3%), and 9 G3 (11.7%). Ten (13.0%) and 24 (31.2%) patients had lymph node and distant metastasis, respectively. In addition, type 3 g-NETs were heterogeneous. Compared with G1 NETs, G2 NETs had a higher lymph node metastasis rate, and G3 NETs had a higher distant metastasis rate. G1 and G2 NETs with stage I/II disease (33/68) received endoscopic treatment, and no tumour recurrence or tumour-related death was observed within a median follow-up time of 36 mo. Grade and distant metastasis were identified to be independent risk factors for prognosis in multivariable analysis. CONCLUSION: Type 3 g-NETs are obviously heterogeneous, and the updated WHO 2019 pathological classification may be used to effectively evaluate their biological behaviors and prognosis. Also, endoscopic treatment should be considered for small (< 2 cm), low grade, superficial tumours.

19.
Cell ; 182(5): 1109-1124.e25, 2020 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-32841601

RESUMEN

Chloroplasts are crucial players in the activation of defensive hormonal responses during plant-pathogen interactions. Here, we show that a plant virus-encoded protein re-localizes from the plasma membrane to chloroplasts upon activation of plant defense, interfering with the chloroplast-dependent anti-viral salicylic acid (SA) biosynthesis. Strikingly, we have found that plant pathogens from different kingdoms seem to have convergently evolved to target chloroplasts and impair SA-dependent defenses following an association with membranes, which relies on the co-existence of two subcellular targeting signals, an N-myristoylation site and a chloroplast transit peptide. This pattern is also present in plant proteins, at least one of which conversely activates SA defenses from the chloroplast. Taken together, our results suggest that a pathway linking plasma membrane to chloroplasts and activating defense exists in plants and that such pathway has been co-opted by plant pathogens during host-pathogen co-evolution to promote virulence through suppression of SA responses.


Asunto(s)
Membrana Celular/inmunología , Cloroplastos/inmunología , Enfermedades de las Plantas/inmunología , Inmunidad de la Planta/inmunología , Transducción de Señal/inmunología , Proteínas de Arabidopsis/inmunología , Interacciones Huésped-Patógeno/inmunología , Ácido Salicílico/inmunología , Virulencia/inmunología
20.
Int J Biol Macromol ; 161: 177-186, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32470582

RESUMEN

Cellulose is an abundant feedstock with renewability and biodegradability. However, it is still challenging to manufacture natural cellulose products by environmentally friendly thermoplastic processing methods. Herein, we proposed a green approach for the heterogeneous preparation of thermoplastic cellulose grafted polyurethane (RCP-g-PU) from amorphous regenerated cellulose paste (RCP) via hydroxyl/isocyanate chemistry. First, amorphous RCP was fabricated through dissolving cellulose in sodium hydroxide aqueous solution and regenerating in polyethylene glycol, resulting in the enhancement of the accessibility of hydroxy groups in cellulose chains. Subsequently, a series of thermoplastic RCP-g-PU with the melt flow temperatures ranging from 160 °C to 226 °C were feasibly synthesized by adding hexamethylene diisocyanate into RCP without using other organic solvents. Eventually, the resultant RCP-g-PU can be directly hot-pressed into transparent films with flexibility and foldability. The reported methodology represents a sustainable route to achieve thermoplastic cellulose derivatives.


Asunto(s)
Celulosa/química , Poliuretanos/química , Fenómenos Químicos , Espectroscopía de Resonancia Magnética , Fenómenos Mecánicos , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Termogravimetría
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