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1.
Plant Cell ; 35(9): 3604-3625, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37325884

RESUMO

Catalase (CAT) is often phosphorylated and activated by protein kinases to maintain hydrogen peroxide (H2O2) homeostasis and protect cells against stresses, but whether and how CAT is switched off by protein phosphatases remains inconclusive. Here, we identified a manganese (Mn2+)-dependent protein phosphatase, which we named PHOSPHATASE OF CATALASE 1 (PC1), from rice (Oryza sativa L.) that negatively regulates salt and oxidative stress tolerance. PC1 specifically dephosphorylates CatC at Ser-9 to inhibit its tetramerization and thus activity in the peroxisome. PC1 overexpressing lines exhibited hypersensitivity to salt and oxidative stresses with a lower phospho-serine level of CATs. Phosphatase activity and seminal root growth assays indicated that PC1 promotes growth and plays a vital role during the transition from salt stress to normal growth conditions. Our findings demonstrate that PC1 acts as a molecular switch to dephosphorylate and deactivate CatC and negatively regulate H2O2 homeostasis and salt tolerance in rice. Moreover, knockout of PC1 not only improved H2O2-scavenging capacity and salt tolerance but also limited rice grain yield loss under salt stress conditions. Together, these results shed light on the mechanisms that switch off CAT and provide a strategy for breeding highly salt-tolerant rice.


Assuntos
Oryza , Catalase/genética , Catalase/metabolismo , Oryza/metabolismo , Peróxido de Hidrogênio/metabolismo , Proteína Fosfatase 1/metabolismo , Tolerância ao Sal/genética , Homeostase , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
2.
J Transl Med ; 22(1): 173, 2024 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-38369516

RESUMO

Lung cancer, a prevalent and aggressive disease, is characterized by recurrence and drug resistance. It is essential to comprehend the fundamental processes and discover novel therapeutic objectives for augmenting treatment results. Based on our research findings, we have identified a correlation between methylation of cg09897064 and decreased expression of ZBP1, indicating a link to unfavorable prognosis in patients with lung cancer. Furthermore, these factors play a role in macrophage polarization, with ZBP1 upregulated in M1 macrophages compared to both M0 and M2 polarized macrophages. We observed cg09897064 methylation in M2 polarization, but not in M0 and M1 polarized macrophages. ATACseq analysis revealed closed chromatin accessibility of ZBP1 in M0 polarized macrophages, while open accessibility was observed in both M1 and M2 polarized macrophages. Our findings suggest that ZBP1 is downregulated in M0 polarized macrophages due to closed chromatin accessibility and downregulated in M2 polarized macrophages due to cg09897064 methylation. Further investigations manipulating cg09897064 methylation and ZBP1 expression through overexpression plasmids and shRNAs provided evidence for their role in modulating macrophage polarization and tumor growth. ZBP1 inhibits M2 polarization and suppresses tumor growth, while cg09897064 methylation promotes M2 polarization and macrophage-induced tumor growth. In mechanism investigations, we found that cg09897064 methylation impairs CEBPA binding to the ZBP1 promoter, leading to decreased ZBP1 expression. Clinical experiments were conducted to validate the correlation between methylation at cg09897064, ZBP1 expression, and macrophage M2 polarization. Targeting these factors may hold promise as a strategy for developing innovative checkpoint inhibitors in lung cancer treatment.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Proteínas de Ligação a RNA , Humanos , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Cromatina/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Macrófagos/metabolismo , Metilação , Proteínas de Ligação a RNA/genética
3.
Br J Surg ; 111(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37943801

RESUMO

BACKGROUND: Right hemicolectomy is the standard treatment for right-sided colon cancer. There is variation in the technical aspects of performing right hemicolectomy as well as in short-term outcomes. It is therefore necessary to explore best clinical practice following right hemicolectomy in expert centres. METHODS: This snapshot study of right hemicolectomy for colon cancer in China was a prospective, multicentre cohort study in which 52 tertiary hospitals participated. Eligible patients with stage I-III right-sided colon cancer who underwent elective right hemicolectomy were consecutively enrolled in all centres over 10 months. The primary endpoint was the incidence of postoperative 30-day anastomotic leak. RESULTS: Of the 1854 patients, 89.9 per cent underwent laparoscopic surgery and 52.3 per cent underwent D3 lymph node dissection. The overall 30-day morbidity and mortality were 11.7 and 0.2 per cent, respectively. The 30-day anastomotic leak rate was 1.4 per cent. In multivariate analysis, ASA grade > II (P < 0.001), intraoperative blood loss > 50 ml (P = 0.044) and D3 lymph node dissection (P = 0.008) were identified as independent risk factors for postoperative morbidity. Extracorporeal side-to-side anastomosis (P = 0.031), intraoperative blood loss > 50 ml (P = 0.004) and neoadjuvant chemotherapy (P = 0.004) were identified as independent risk factors for anastomotic leak. CONCLUSION: In high-volume expert centres in China, laparoscopic resection with D3 lymph node dissection was performed in most patients with right-sided colon cancer, and overall postoperative morbidity and mortality was low. Further studies are needed to explore the optimal technique for right hemicolectomy in order to improve outcomes further.


Assuntos
Neoplasias do Colo , Laparoscopia , Humanos , Fístula Anastomótica/epidemiologia , Fístula Anastomótica/etiologia , Fístula Anastomótica/cirurgia , Estudos de Coortes , Estudos Prospectivos , Perda Sanguínea Cirúrgica , Neoplasias do Colo/patologia , Colectomia/efeitos adversos , Colectomia/métodos , Morbidade , Fatores de Risco , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Estudos Retrospectivos
4.
BMC Public Health ; 23(1): 2534, 2023 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-38110887

RESUMO

BACKGROUND: Colorectal cancer (CRC) screening faces two major challenges: insufficient screening coverage and poor adherence. A smartphone applet named "Early Screening Assistant (ESA)" was developed to create an online risk-assessment and fecal occult blood test (FOBT) at home. This retrospective study was designed to evaluate whether the new CRC screening strategy can improve the colonoscopy participation rate (PR) and lesion detection rate (DR). METHODS: In total, 6194 individuals who accepted normal health examinations and CRC screening based on the ESA from June 2020 to May 2022 were assigned to the ESA group. Accordingly, 7923 inhabitants who only accepted normal health examinations were assigned to the control group. The colonoscopy PR and neoplastic lesion DR were then compared between the two groups. RESULTS: Overall, a higher proportion of subjects in the ESA group (285 of 6194 [4.6%]) completed colonoscopy than in the control group (126 of 7923, [1.6%]), p < 0.01). The neoplastic lesion DR also significantly increased in the ESA group (76 of 6194 [1.22%]) compared with the control group (15 of 7923 [0.19%]) (p < 0.01). The adjusted diagnostic sensitivity and specificity of the "Online assessment + FOBT at home" were 41.5% and 62.6% for neoplastic lesions, respectively. CONCLUSIONS: This retrospective cohort study confirmed that the new CRC screening strategy based on the "Online assessment + FOBT at home" can improve colonoscopy participation and the neoplastic lesion detection rate and may represent a promising screening strategy for CRC. TRIAL REGISTRATION: This study was registered in China Clinical Trial Registry ( https://www.chictr.org.cn ) on 29/09/2022. REGISTRATION NUMBER: ChiCTR2200064186.


Assuntos
Neoplasias Colorretais , Sangue Oculto , Humanos , Estudos Retrospectivos , Detecção Precoce de Câncer , Programas de Rastreamento , Colonoscopia , Neoplasias Colorretais/diagnóstico
5.
Int J Mol Sci ; 24(9)2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37175986

RESUMO

In this study, a commercial agent with antivirus activity and moroxydine hydrochloride were employed to perform a lead optimization. A series of 1,3,5-triazine derivatives with piperazine structures were devised and synthesized, and an evaluation of their anti-potato virus Y (PVY) activity revealed that several of the target compounds possessed potent anti-PVY activity. The synthesis of compound C35 was directed by a 3D-quantitative structure-activity relationship that used the compound's structural parameters. The assessment of the anti-PVY activity of compound C35 revealed that its curative, protective, and inactivation activities (53.3 ± 2.5%, 56.9 ± 1.5%, and 85.8 ± 4.4%, respectively) were comparable to the positive control of ningnanmycin (49.1 ± 2.4%, 50.7 ± 4.1%, and 82.3 ± 6.4%) and were superior to moroxydine hydrochloride (36.7 ± 2.7%, 31.4 ± 2.0%, and 57.1 ± 1.8%). In addition, molecular docking demonstrated that C35 can form hydrogen bonds with glutamic acid at position 150 (GLU 150) of PVY CP, providing a partial theoretical basis for the antiviral activity of the target compounds.


Assuntos
Potyvirus , Vírus do Mosaico do Tabaco , Piperazina , Simulação de Acoplamento Molecular , Antivirais/química , Triazinas/farmacologia
6.
BMC Infect Dis ; 22(1): 880, 2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36424534

RESUMO

The Omicron transmission has infected nearly 600,000 people in Shanghai from March 26 to May 31, 2022. Combined with different control measures taken by the government in different periods, a dynamic model was constructed to investigate the impact of medical resources, shelter hospitals and aerosol transmission generated by clustered nucleic acid testing on the spread of Omicron. The parameters of the model were estimated by least square method and MCMC method, and the accuracy of the model was verified by the cumulative number of asymptomatic infected persons and confirmed cases in Shanghai from March 26 to May 31, 2022. The result of numerical simulation demonstrated that the aerosol transmission figured prominently in the transmission of Omicron in Shanghai from March 28 to April 30. Without aerosol transmission, the number of asymptomatic subjects and symptomatic cases would be reduced to 130,000 and 11,730 by May 31, respectively. Without the expansion of shelter hospitals in the second phase, the final size of asymptomatic subjects and symptomatic cases might reach 23.2 million and 4.88 million by May 31, respectively. Our results also revealed that expanded vaccination played a vital role in controlling the spread of Omicron. However, even if the vaccination rate were 100%, the transmission of Omicron should not be completely blocked. Therefore, other control measures should be taken to curb the spread of Omicron, such as widespread antiviral therapies, enhanced testing and strict tracking quarantine measures. This perspective could be utilized as a reference for the transmission and prevention of Omicron in other large cities with a population of 10 million like Shanghai.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/prevenção & controle , China/epidemiologia , Quarentena , Aerossóis e Gotículas Respiratórios
7.
Cochrane Database Syst Rev ; 3: CD009569, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35288930

RESUMO

BACKGROUND: This is the second update of a Cochrane Review first published in 2013 and last updated in 2017. Laparoscopic surgery is now widely performed to treat various abdominal diseases. Currently, carbon dioxide is the most frequently used gas for insufflation of the abdominal cavity (pneumoperitoneum). Although carbon dioxide meets most of the requirements for pneumoperitoneum, the absorption of carbon dioxide may be associated with adverse events. Therefore, other gases have been introduced as alternatives to carbon dioxide for establishing pneumoperitoneum. OBJECTIVES: To assess the safety, benefits, and harms of different gases (e.g. carbon dioxide, helium, argon, nitrogen, nitrous oxide, and room air) used for establishing pneumoperitoneum in participants undergoing laparoscopic abdominal or gynaecological pelvic surgery. SEARCH METHODS: We searched CENTRAL, Ovid MEDLINE, Ovid Embase, four other databases, and three trials registers on 15 October 2021 together with reference checking, citation searching, and contact with study authors to identify additional studies. SELECTION CRITERIA: We included randomised controlled trials (RCTs) comparing different gases for establishing pneumoperitoneum in participants (irrespective of age, sex, or race) undergoing laparoscopic abdominal or gynaecological pelvic surgery under general anaesthesia. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. MAIN RESULTS: We included 10 RCTs, randomising 583 participants, comparing different gases for establishing pneumoperitoneum: nitrous oxide (four trials), helium (five trials), or room air (one trial) was compared to carbon dioxide. All the RCTs were single-centre studies. Four RCTs were conducted in the USA; two in Australia; one in China; one in Finland; one in Iran; and one in the Netherlands. The mean age of the participants ranged from 27.6 years to 49.0 years. Four trials randomised participants to nitrous oxide pneumoperitoneum (132 participants) or carbon dioxide pneumoperitoneum (128 participants). None of the trials was at low risk of bias. The evidence is very uncertain about the effects of nitrous oxide pneumoperitoneum compared to carbon dioxide pneumoperitoneum on cardiopulmonary complications (Peto odds ratio (OR) 2.62, 95% CI 0.78 to 8.85; 3 studies, 204 participants; very low-certainty evidence), or surgical morbidity (Peto OR 1.01, 95% CI 0.14 to 7.31; 3 studies, 207 participants; very low-certainty evidence). There were no serious adverse events related to either nitrous oxide or carbon dioxide pneumoperitoneum (4 studies, 260 participants; very low-certainty evidence). Four trials randomised participants to helium pneumoperitoneum (69 participants) or carbon dioxide pneumoperitoneum (75 participants) and one trial involving 33 participants did not state the number of participants in each group. None of the trials was at low risk of bias. The evidence is very uncertain about the effects of helium pneumoperitoneum compared to carbon dioxide pneumoperitoneum on cardiopulmonary complications (Peto OR 1.66, 95% CI 0.28 to 9.72; 3 studies, 128 participants; very low-certainty evidence), or surgical morbidity (5 studies, 177 participants; very low-certainty evidence). There were three serious adverse events (subcutaneous emphysema) related to helium pneumoperitoneum (3 studies, 128 participants; very low-certainty evidence). One trial randomised participants to room air pneumoperitoneum (70 participants) or carbon dioxide pneumoperitoneum (76 participants). The trial was at high risk of bias. There were no cardiopulmonary complications, serious adverse events, or deaths observed related to either room air or carbon dioxide pneumoperitoneum.    AUTHORS' CONCLUSIONS: The evidence is very uncertain about the effects of nitrous oxide, helium, and room air pneumoperitoneum compared to carbon dioxide pneumoperitoneum on any of the primary outcomes, including cardiopulmonary complications, surgical morbidity, and serious adverse events. The safety of nitrous oxide, helium, and room air pneumoperitoneum has yet to be established, especially in people with high anaesthetic risk.


Assuntos
Insuflação , Laparoscopia , Pneumoperitônio , Adulto , Dióxido de Carbono/efeitos adversos , Hélio/efeitos adversos , Humanos , Insuflação/efeitos adversos , Insuflação/métodos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Óxido Nitroso/efeitos adversos , Pneumoperitônio/etiologia
8.
J Surg Oncol ; 124(8): 1451-1458, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34510454

RESUMO

BACKGROUND AND OBJECTIVES: To analyze and evaluate the impact of preoperative transcatheter rectal arterial chemoembolization (TRACE) with concurrent chemoradiotherapy on surgery and prognosis of locally advanced rectal cancer (LARC). METHODS: A total of 118 patients with LARC were enrolled in this nonrandomized prospective study. They were assigned into the experimental group receiving preoperative TRACE with concurrent chemoradiotherapy (TRACE-CRT group, N = 60) and the control group receiving only neoadjuvant chemoradiotherapy (CRT group, N = 58). All patients underwent surgery after their preoperative treatments. RESULTS: All patients successfully completed the surgical operation. No significant differences were found in sphincter preservation rate and R0 resection rate between TRACE-CRT group and CRT group (p > 0.05). No significant differences were found between the two groups in terms of the perioperative indicators and postoperative complications except mean operation time (165.8 vs. 196.6 min, p < 0.001). Local recurrence occurred in 8 and 5 patients, respectively (p > 0.05). Distant metastasis occurred in 5 and 11 patients, respectively (p < 0.05). CONCLUSIONS: Adding TRACE in the preoperative standard treatment for LARC did not increase perioperative complications. In addition, it has the potential advantage of preventing distant metastasis. It is worthy of further application and promotion in clinical practice.


Assuntos
Quimioembolização Terapêutica/mortalidade , Quimiorradioterapia/mortalidade , Recidiva Local de Neoplasia/mortalidade , Cuidados Pré-Operatórios , Neoplasias Retais/mortalidade , Terapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/terapia , Ensaios Clínicos Controlados não Aleatórios como Assunto , Prognóstico , Estudos Prospectivos , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Taxa de Sobrevida
9.
Biophys J ; 118(4): 898-908, 2020 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-31699333

RESUMO

Defective nitrate signaling in plants causes disorder in nitrogen metabolism, and it negatively affects nitrate transport systems, which toggle between high- and low-affinity modes in variable soil nitrate conditions. Recent discovery of a plasma membrane nitrate transceptor protein NRT1.1-a transporter cum sensor-provides a clue on this toggling mechanism. However, the general mechanistic description still remains poorly understood. Here, we illustrate adaptive responses and regulation of NRT1.1-mediated nitrate signaling in a wide range of extracellular nitrate concentrations. The results show that the homodimeric structure of NRT1.1 and its dimeric switch play an important role in eliciting specific cytosolic calcium waves sensed by the calcineurin-B-like calcium sensor CBL9, which activates the kinase CIPK23, in low nitrate concentration that is, however, impeded in high nitrate concentration. Nitrate binding at the high-affinity unit initiates NRT1.1 dimer decoupling and priming of the Thr101 site for phosphorylation by CIPK23. This phosphorylation stabilizes the NRT1.1 monomeric state, acting as a high-affinity nitrate transceptor. However, nitrate binding in both monomers, retaining the unmodified NRT1.1 state through dimerization, attenuates CIPK23 activity and thereby maintains the low-affinity mode of nitrate signaling and transport. This phosphorylation-led modulation of NRT1.1 activity shows bistable behavior controlled by an incoherent feedforward loop, which integrates nitrate-induced positive and negative regulatory effects on CIPK23. These results, therefore, advance our molecular understanding of adaptation in fluctuating nutrient availability and are a way forward for improving plant nitrogen use efficiency.


Assuntos
Arabidopsis , Nitratos , Proteínas de Transporte de Ânions , Arabidopsis/metabolismo , Transportadores de Nitrato , Nitratos/metabolismo , Proteínas de Plantas/metabolismo
10.
Entropy (Basel) ; 22(9)2020 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-33286794

RESUMO

As humanity struggles to find a path to resilience amidst global change vagaries, understanding organizing principles of living systems as the pillar for human existence is rapidly growing in importance. However, finding quantitative definitions for order, complexity, information and functionality of living systems remains a challenge. Here, we review and develop insights into this problem from the concept of the biotic regulation of the environment developed by Victor Gorshkov (1935-2019). Life's extraordinary persistence-despite being a strongly non-equilibrium process-requires a quantum-classical duality: the program of life is written in molecules and thus can be copied without information loss, while life's interaction with its non-equilibrium environment is performed by macroscopic classical objects (living individuals) that age. Life's key energetic parameter, the volume-specific rate of energy consumption, is maintained within universal limits by most life forms. Contrary to previous suggestions, it cannot serve as a proxy for "evolutionary progress". In contrast, ecosystem-level surface-specific energy consumption declines with growing animal body size in stable ecosystems. High consumption by big animals is associated with instability. We suggest that the evolutionary increase in body size may represent a spontaneous loss of information about environmental regulation, a manifestation of life's algorithm ageing as a whole.

11.
Langmuir ; 34(3): 1073-1083, 2018 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-29035563

RESUMO

Selective localization of graphene in co-continuous polymer blends is an attractive method for preparing conductive polymer composites. Localization of graphene at the interface between the two polymer phases produces good conductivity at ultra-low concentrations. Although graphene localization is ultimately dependent on thermodynamic factors such as the surface energy of graphene and the two polymer components, kinetics also strongly affects the migration and localization of graphene in polymer blends during melt compounding. However, few studies have systemically investigated the important role of kinetics on graphene localization. Here, we introduced graphene nanoplatelets (GNPs) in polylactic acid (PLA)/polystyrene (PS) co-continuous polymer blends. Although GNPs in thermal equilibrium prefer the PS phase, we were able to kinetically trap GNPs at the interface of polymer blends via control of melt-compounding sequences, mixing times and shear rates. Utilizing morphological, rheological, and electrical measurements, we verified graphene localization and the suppression of coarsening in co-continuous polymer blends during annealing. When GNPs were premixed with the thermodynamically less-favorable PLA phase before mixing with the PS phase, GNPs can be kinetically trapped at the interface during melt compounding. Moreover, we show that a shorter melt-compounding time gives rise to a higher GNP interfacial coverage and a more effective morphology stabilization effect. Blends with as low as 0.5 wt % GNPs with only 30 s of melt compounding have a room-temperature conductivity of ∼10-6 S/cm, which is larger than blends with longer melt-compounding times and potentially useful for antistatic materials. The in-depth study on the kinetics of graphene localization in our work provides a general guideline for the kinetic control of the localization of platelike nanofillers in polymer blends. Our study also demonstrates a facile method for manufacturing conductive polymer blends with low percolation thresholds.

12.
Cochrane Database Syst Rev ; 6: CD009569, 2017 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-28635028

RESUMO

BACKGROUND: This is an update of the review published in 2013.Laparoscopic surgery is now widely performed to treat various abdominal diseases. Currently, carbon dioxide is the most frequently used gas for insufflation of the abdominal cavity (pneumoperitoneum). Although carbon dioxide meets most of the requirements for pneumoperitoneum, the absorption of carbon dioxide may be associated with adverse events. People with high anaesthetic risk are more likely to experience cardiopulmonary complications and adverse events, for example hypercapnia and acidosis, which has to be avoided by hyperventilation. Therefore, other gases have been introduced as alternatives to carbon dioxide for establishing pneumoperitoneum. OBJECTIVES: To assess the safety, benefits, and harms of different gases (i.e. carbon dioxide, helium, argon, nitrogen, nitrous oxide, and room air) used for establishing pneumoperitoneum in participants undergoing laparoscopic general abdominal or gynaecological pelvic surgery. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2016, Issue 9), Ovid MEDLINE (1950 to September 2016), Ovid Embase (1974 to September 2016), Science Citation Index Expanded (1970 to September 2016), Chinese Biomedical Literature Database (CBM) (1978 to September 2016), ClinicalTrials.gov (September 2016), and World Health Organization International Clinical Trials Registry Platform (September 2016). SELECTION CRITERIA: We included randomised controlled trials (RCTs) comparing different gases for establishing pneumoperitoneum in participants (irrespective of age, sex, or race) undergoing laparoscopic abdominal or gynaecological pelvic surgery under general anaesthesia. DATA COLLECTION AND ANALYSIS: Two review authors identified the trials for inclusion, collected the data, and assessed the risk of bias independently. We performed the meta-analyses using Review Manager 5. We calculated risk ratio (RR) for dichotomous outcomes (or Peto odds ratio for very rare outcomes), and mean difference (MD) or standardised mean difference (SMD) for continuous outcomes with 95% confidence intervals (CI). We used GRADE to rate the quality of evidence, MAIN RESULTS: We included nine RCTs, randomising 519 participants, comparing different gases for establishing pneumoperitoneum: nitrous oxide (three trials), helium (five trials), or room air (one trial) was compared to carbon dioxide. Three trials randomised participants to nitrous oxide pneumoperitoneum (100 participants) or carbon dioxide pneumoperitoneum (96 participants). None of the trials was at low risk of bias. There was insufficient evidence to determine the effects of nitrous oxide and carbon dioxide on cardiopulmonary complications (RR 2.00, 95% CI 0.38 to 10.43; two studies; 140 participants; very low quality of evidence), or surgical morbidity (RR 1.01, 95% CI 0.18 to 5.71; two studies; 143 participants; very low quality of evidence). There were no serious adverse events related to either nitrous oxide or carbon dioxide pneumoperitoneum (three studies; 196 participants; very low quality of evidence). We could not combine data from two trials (140 participants) which individually showed lower pain scores (a difference of about one visual analogue score on a scale of 1 to 10 with lower numbers indicating less pain) with nitrous oxide pneumoperitoneum at various time points on the first postoperative day, and this was rated asvery low quality .Four trials randomised participants to helium pneumoperitoneum (69 participants) or carbon dioxide pneumoperitoneum (75 participants) and one trial involving 33 participants did not state the number of participants in each group. None of the trials was at low risk of bias. There was insufficient evidence to determine the effects of helium or carbon dioxide on cardiopulmonary complications (RR 1.46, 95% CI 0.35 to 6.12; three studies; 128 participants; very low quality of evidence) or pain scores (visual analogue score on a scale of 1 to 10 with lower numbers indicating less pain; MD 0.49 cm, 95% CI -0.28 to 1.26; two studies; 108 participants; very low quality of evidence). There were three serious adverse events (subcutaneous emphysema) related to helium pneumoperitoneum (three studies; 128 participants; very low quality of evidence).One trial randomised participants to room air pneumoperitoneum (70 participants) or carbon dioxide pneumoperitoneum (76 participants). The trial was at unclear risk of bias. There were no cardiopulmonary complications or serious adverse events observed related to either room air or carbon dioxide pneumoperitoneum (both outcomes very low quality of evidence). The evidence of lower hospital costs and reduced pain during the first postoperative day with room air pneumoperitoneum compared with carbon dioxide pneumoperitoneum (a difference of about one visual analogue score on a scale of 1 to 10 with lower numbers indicating less pain, was rated as very low quality of evidence. AUTHORS' CONCLUSIONS: The quality of the current evidence is very low. The effects of nitrous oxide and helium pneumoperitoneum compared with carbon dioxide pneumoperitoneum are uncertain. Evidence from one trial of small sample size suggests that room air pneumoperitoneum may decrease hospital costs in people undergoing laparoscopic abdominal surgery. The safety of nitrous oxide, helium, and room air pneumoperitoneum has yet to be established.Further trials on this topic are needed, and should compare various gases (i.e. nitrous oxide, helium, argon, nitrogen, and room air) with carbon dioxide under standard pressure pneumoperitoneum with cold gas insufflation for people with high anaesthetic risk. Future trials should include outcomes such as complications, serious adverse events, quality of life, and pain.


Assuntos
Abdome/cirurgia , Ar , Dióxido de Carbono , Hélio , Laparoscopia/métodos , Óxido Nitroso , Pneumoperitônio Artificial/métodos , Analgesia/estatística & dados numéricos , Dióxido de Carbono/efeitos adversos , Hélio/efeitos adversos , Humanos , Óxido Nitroso/efeitos adversos , Pneumoperitônio Artificial/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
Mar Drugs ; 15(11)2017 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-29125577

RESUMO

Anandins A (1) and B (2), two rare steroidal alkaloids, were isolated from the fermentative broth of a marine actinobacteria Streptomyces anandii H41-59. The gross structures of the two alkaloids were elucidated by spectroscopic methods including HR-ESI-MS, and NMR. Their absolute configurations were confirmed by single-crystal X-ray diffraction analysis and comparison of their experimental and calculated electronic circular dichroism spectra, respectively. Anandin A exhibited a moderate inhibitory effect against three human cancer cell lines MCF-7, SF-268, and NCI-H460 with IC50 values of 7.5, 7.9, 7.8 µg/mL, respectively.


Assuntos
Alcaloides/química , Esteroides/química , Streptomyces/metabolismo , Alcaloides/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Organismos Aquáticos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Modelos Moleculares , Esteroides/farmacologia
14.
Tumour Biol ; 37(7): 8941-9, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26753960

RESUMO

In this study, we investigated the functional mechanisms of microRNA-193-3p (miR-193-3p) in human gastric cancer. Quantitative RT-PCR (qRT-PCR) was used to assess whether miR-193-3p was aberrantly expressed in gastric cancer cells and clinical samples from gastric cancer patients. Gastric cancer cell line AGS and MKN-45 cells were stably transduced with lentivirus to downregulate endogenous miR-193-3p. The modulation of miR-193-3p downregulation on gastric cancer proliferation, migration, chemo-drug responses, and tumor explant were assessed by MTT, wound-healing, 5-FU chemoresistance and in vivo tumorigenicity assays, respectively. Downstream target of miR-193-3p, phosphatase and tensin homolog (PTEN) in gastric cancer, was assessed by dual-luciferase reporter assay, qRT-PCR, and western blot. PTEN was knocked down by siRNA in AGS and MKN-45 cells to assess its direct impact on miR-193-3p modulation in gastric cancer. MiR-193-3p was aberrantly upregulated in both gastric cell lines and human gastric tumors. In AGS and MKN-45 cells, miR-193-3p downregulation reduced cancer proliferation, migration and 5-FU chemoresistance in vitro, and tumorigenicity in vivo. PTEN was confirmed to be targeted by miR-193-3p in gastric cancer. PTEN inhibition in AGS and MKN-45 cells directly reversed the anti-tumor modulations of miR-193-3p downregulation on gastric cancer proliferation, migration, and 5-FU chemoresistance. We presented clear evidence showing miR-193-3p played critical role in regulating human gastric cancer through direct targeting on PTEN gene.


Assuntos
Movimento Celular/genética , Proliferação de Células/genética , Regulação para Baixo/genética , Resistencia a Medicamentos Antineoplásicos/genética , MicroRNAs/genética , PTEN Fosfo-Hidrolase/genética , Neoplasias Gástricas/genética , Animais , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Feminino , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Camundongos , Camundongos Nus , Invasividade Neoplásica/genética , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/parasitologia , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
15.
J Nanosci Nanotechnol ; 16(1): 840-3, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27398533

RESUMO

A colorimetric assay has been developed for detection of Cd²âº utilizing DL-mercaptosuccinic acid-modified gold nanoparticles (MSA-AuNPs). The method showed good selectivity for Cd²âº over other metal ions. As a result, the linear relationships (r > 0.9606) between concentration 0.07 mM and 0.20 mM for cadmium ion were obtained. The detection limit was as low as 0.07 mM by the naked eye. The effect of pH on the aggregation was optimized. The MSA-AuNPs probe could be used to detect Cd²âº in an aqueous solution based on the aggregation-induced color change of MSA-AuNPs.


Assuntos
Cádmio/análise , Ouro/química , Nanopartículas Metálicas/química , Tiomalatos/química , Íons/análise
16.
Zhong Yao Cai ; 39(3): 559-61, 2016 Mar.
Artigo em Zh | MEDLINE | ID: mdl-30088886

RESUMO

Objective: To study the non-alkaloid chemical constituents of Macleaya cordata. Methods: Alcohol extraction and liquidliquid partitionmethods were used to extract the chemical constituents. Silica gel,reverse-phase octadecylsilyl( ODS), and Sephadex LH-20 column chromatographic methods were applied for isolation and purification. Spectroscopic methods including MS and NMR were used to determine their structures. Results: Eleven non-alkaloid compounds were isolated from the fruits of Macleaya cordata, and their structures were identified as 3-( 3,4-dihydroxy) phenylpropanoic acid methyl ester( 1),ferulic acid( 2),1-octacosanol( 3),syringic acid( 4),p-hydroxy-benzoic acid( 5),p-coumaric acid( 6),quercetin-3-O-ß-D-glucoside( 7),N-p-coumaroyl tyramine( 8),10-eicosenoic acid( 9) and ß-sitosterol( 10) and daucosterol( 11). Conclusion: Compounds 1,3 ~9 are isolated from Macleaya cordata for the first time.


Assuntos
Papaveraceae , Alcaloides , Ácidos Cumáricos , Ácido Gálico/análogos & derivados , Glucosídeos , Quercetina , Sitosteroides , Tiramina/análogos & derivados
17.
Soft Matter ; 11(26): 5282-93, 2015 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-26053792

RESUMO

Bicontinuous, interfacially jammed, emulsion gels (bijels) are a novel class of materials composed of two immiscible phases with interpenetrating domains that are stabilized by a monolayer of colloidal particles at the interface. However, existing bijel systems so far all consist of at least one polar fluid, which is believed to be essential to induce electrostatic repulsion for stabilizing interfacial particles. It is not known whether two nonpolar fluids can form a bijel. Here, we experimentally achieve a bijel using styrene trimer and low molecular weight polybutene-two nonpolar fluids that are similar to polymer blends, which are important in technical applications. By combining laser scanning confocal microscopy, cryo-SEM and rheology measurement, we systematically investigate the dynamics and rheology of this nonpolar bijel. In contrast to previous studies on polar bijels, we observe the formation of localized regions of high particle concentration or "particle patches" on the interface which assemble during coarsening. We also provide the first quantitative relation between the morphology of a bijel, the interfacial particle coverage and the shear modulus during bijel coarsening. Moreover, we reveal a previously unnoticed increase in the elastic modulus of bijels that can be attributed to the rearrangement of interfacial particles at long time scales. In addition, we also found a hydrophobic particle framework that survives after the direct remixing of the nonpolar bijel. Our study provides important insights into the formation of bijels and is the first step to explore the missing link between polar bijels and particle-stabilized bicontinuous polymer blends.

18.
J Asian Nat Prod Res ; 17(7): 778-82, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25492028

RESUMO

The leaves of Rhododendron seniavinii Maxim with little phytochemical information are used as folk remedies for the treatment of acute and chronic bronchitis in China. In our pursuing for the biologically active chemical constituents in the leaves, a new flavonoid glycoside 5,7,3'-trimethoxy-quercetin-3-O-ß-D-glucopyranoside (1) was isolated from the water extract of its leaves, together with two known compounds 5,7,3'-trimethoxy-quercetin (2) and ovafolinin B-9'-O-ß-D-glucopyranoside (3). The structures of the new flavonoid glucoside as well as two known compounds were elucidated by spectroscopic and chemical methods.


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Flavonoides/isolamento & purificação , Glucosídeos/isolamento & purificação , Quercetina/análogos & derivados , Quercetina/isolamento & purificação , Rhododendron/química , China , Medicamentos de Ervas Chinesas/química , Flavonoides/química , Glucosídeos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química , Quercetina/química
19.
J Asian Nat Prod Res ; 17(8): 856-60, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25761206

RESUMO

A new cytotoxic benzophenanthridine isoquinoline alkaloid, named cordatine (1), together with one known alkaloid 8-methoxydihydrochelerythrine (2), was isolated from the fruits of Macleaya cordata. The structure of the new compound was elucidated by spectroscopic methods including 1D and 2D NMR, HR-ESI-MS. Both compounds indicated significant cytotoxicity against MCF-7 and SF-268 cell lines.


Assuntos
Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Benzofenantridinas/isolamento & purificação , Benzofenantridinas/farmacologia , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Frutas/química , Papaveraceae/química , Alcaloides/química , Antineoplásicos Fitogênicos/química , Benzofenantridinas/química , Ensaios de Seleção de Medicamentos Antitumorais , Medicamentos de Ervas Chinesas/química , Humanos , Isoquinolinas , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular
20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(5): 1414-8, 2015 May.
Artigo em Zh | MEDLINE | ID: mdl-26415470

RESUMO

In the reflection-based imaging spectrometer, multiple reflection(diffraction) produces stray light and it is difficult to assemble. To address that, a high performance transmission spectral imaging system based on general optical components was developed. On the basis of simple structure, the system is easy to assemble. And it has wide application and low cost compared to traditional imaging spectrometers. All components in the design can be replaced according to different application situations, having high degree of freedom. In order to reduce the influence of stray light, a method based on transmission was introduced. Two sets of optical systems with different objective lenses were simulated; the parameters such as distortion, MTF and aberration.were analyzed and optimized in the ZEMAX software. By comparing the performance of system with different objective len 25 and 50 mm, it can be concluded that the replacement of telescope lens has little effect on imaging quality of whole system. An imaging spectrometer is developed successfully according design parameters. The telescope lens uses double Gauss structures, which is beneficial to reduce field curvature and distortion. As the craftsmanship of transmission-type plane diffraction grating is mature, it can be used without modification and it is easy to assemble, so it is used as beam-split. component of the imaging spectrometer. In addition, the real imaging spectrometer was tested for spectral resolution and distortion. The result demonstrates that the system has good ability in distortion control, and spectral resolution is 2 nm. These data satisfy the design requirement, and obtained spectrum of deuterium lamp through calibrated system are ideal results.

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