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1.
Nanotechnology ; 31(24): 24LT02, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32126544

RESUMO

The emerging materials of semiconductor quantum dots/graphene oxide (QDs/GO) hybrid composites have recently attracted intensive attention in materials science and technology due to their potential applications in electronic and photonic devices. Here, a simple and universal strategy to produce DNA-programmed semiconductor quantum dots/graphene oxide (QDs/GO) hybrid composites with controllable sizes, shapes, compositions, and surface properties is reported. This proof-of-concept work successfully demonstrates the use of sulfhydryl modified single-stranded DNA (S-ssDNA) as a 'universal glue' which can adsorb onto GO easily and provide the growth sites to synthesize CdS QDs, CdSe QDs, CdTe QDs and CdTeSe QDs with distinctive sizes, shapes and properties. Also, adapting this method, other graphene oxide-based hybrid materials which are easily synthesized in aqueous solution, including oxides, core-shell structure QDs and metal nanocrystals, would be possible. This method provided a universal strategy for the synthesis and functional realization of graphene -based nanomaterials.


Assuntos
DNA de Cadeia Simples/química , Grafite/química , Pontos Quânticos/química , Tamanho da Partícula , Estudo de Prova de Conceito , Semicondutores , Propriedades de Superfície
2.
Sci Total Environ ; 838(Pt 3): 156532, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35679926

RESUMO

Soil extracellular enzyme activities of microbes to acquire carbon (C), nitrogen (N) and phosphorus (P) exert great roles on soil C sequestration and N, P availability. However, a lack of biochar-induced changes of C, N and P acquisition enzyme activities hinders us from understanding if biochar application will lead to microbial C, N and P limitation based on ecoenzymatic stoichiometry. In this study, through ecoenzymatic stoichiometry, a meta-analysis was conducted to evaluate responses of microbial metabolic limitation to biochar amendment by collecting data of ecoenzymatic activities (EEAs) of the C, N and P acquisition from peer-reviewed papers. The results showed that biochar application increased activities of C, N acquisition enzymes significantly by 9.3 % and 15.1 % on average, respectively. But the influence on P acquisition enzymes activities (Acid, neutral or alkaline phosphatase, abbreviated wholly as PHOS) was not significant. Biochar increased ratio of C acquisition enzymes activities (EC) over P enzymes activities (EP) and ratio of N enzymes activities (EN) over EP, but decreased EC:EN, indicating an increased N limitation or a shift from P limitation to N limitation in microbial metabolism. Enzyme vector analysis showed that soil microbial metabolism was limited by C relative to nutrients (N and P) under biochar amendment according to the overall increased vector length (~1.5 %). Wood biochar caused the strongest microbial C limitation, followed by crop residue biochar as indicated by increased enzyme vector length of 3.6 % and 1.2 % on average, respectively. The stronger microbial C limitation was also found when initial soil total organic carbon (SOC) was <20 g·kg-1. Our results illustrated that available nitrogen and organic carbon should be provided to meet microbial stoichiometric requirements to improve plant productivity, especially in low fertile soils under biochar amendment.


Assuntos
Nitrogênio , Solo , Carbono , Carvão Vegetal/química , Nitrogênio/análise , Fósforo/metabolismo , Solo/química , Microbiologia do Solo
3.
RSC Adv ; 12(49): 31869-31877, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36380926

RESUMO

Multifunctional therapeutic platforms with targeted delivery, fast diagnosis, and efficient therapy could effectively reduce side effects and improve treatment in the clinical therapy of tumors. Near-infrared DNA-templated CdTeSe quantum dots (DNA-CdTeSe QDs) were developed as building blocks to construct a multifunctional carboxymethyl cellulose (CMC)-based nanohydrogel as a nanocarrier to address the challenges of serious side effects and precise treatment in cancer theranostics, including active tumor targeting, fluorescence tracking, controlled drug release, chemotherapy and gene regulation. Single-stranded DNA containing the complementarity sequence of miRNA and cystine, as co-crosslinkers, initiated hybridization between the DNA-CdTeSe QD-modified CMC chain with the anti-nucleolin aptamer DNA (AS1411)-modified CMC chain to form the hydrogels. DOX, as a model drug, was successfully incorporated into the hydrogels. The synthesized multifunctional hydrogel nanocarriers with an average diameter of 150 nm could be taken up through targeting and achieved the controlled release of DOX by triggering both glutathione (GSH) and miRNA in the tumor microenvironment. The CdTeSe QDs trapped in nanohydrogels acted as fluorophores for bioimaging in the diagnosis and treatment process. The proposed multifunctional delivery system provided a potential platform for tumor imaging and precise therapy.

7.
Medicine (Baltimore) ; 98(4): e14286, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30681633

RESUMO

BACKGROUD: The aim of this study was to assess the efficacy and safety of laparoscopic holmium laser lithotripsy (LHLL) in the treatment of complicated biliary calculus. METHODS: We systematically searched the electronic database (PubMed, EMBASE, Cochrane library, Web of science, and Chinese Biomedical Literature Database) up to May 2018 to identify case-controlled studies that compared LHLL with laparoscopic bile duct exploration (LBDE) for complicated biliary calculus. RESULTS: Five case-controlled studies were included, with 541 patients (273 in the LHLL group and 268 in the LBDE group). Compared with LBDE, LHLL was associated with shorter operative time (weighted mean difference [WMD] = -40.04, P < .001) and lower estimated blood loss (EBL) (WMD = -56.42, P < .001), lesser duration of hospitalization (WMD = -3.93, P < .001) and lower rate of residual stone (OR = 0.13, P < .001). There was no statistically significant differences in bile leakage (OR = 0.48, P = .23) and hemobilia (OR = 0.49, 0.41). CONCLUSION: Current evidence suggests that the efficacy of LHLL is superior to that of LBDE but they are similarly safe for the treatment of complicated biliary calculus. Limited by the quantity and quality of the studies included, these conclusions need to be verified by more high-quality studies.


Assuntos
Cálculos Biliares/cirurgia , Laparoscopia/métodos , Lasers de Estado Sólido/uso terapêutico , Litotripsia a Laser/métodos , Estudos de Casos e Controles , Ducto Colédoco/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
8.
Am Surg ; 85(3): 294-302, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30947778

RESUMO

The aim of this study was to evaluate and compare the intestinal function recovery time and other short-term outcomes between robotic-assisted total mesorectal excision (R-TME) and laparoscopic total mesorectal excision (L-TME) for rectal cancer. This is a retrospective study using a prospectively collected database. Patients' records were obtained from Gansu Provincial Hospital between July 2015 and October 2017. Eighty patients underwent R-TME, and 116 with the same histopathological stage of the tumor underwent an L-TME. Both operations were performed by the same surgeon, comparing intra- and postoperative outcomes intergroups. The time to the first passage of flatus (P < 0.001), the time to the first postoperative oral fluid intake (P < 0.001), and the length of hospital stay (P < 0.01) of the R-TME group were about three days faster than those in the L-TME group. The rate of conversion to open laparotomy (P = 0.038) and postoperative urinary retention (P = 0.016) were significantly lower in the R-TME group than in the L-TME group. Intraoperative blood loss of the R-TME group was more than that of the L-TME group (P < 0.01).The operation time, number of lymph nodes harvested, and rate of positive circumferential resection margin were similar intergroup. The total cost of the R-TME group was higher than that of the L-TME group, but with a lack of statistical significance (85,623.91 ± 13,310.50 vs 67,356.79 ± 17,107.68 CNY, P = 0.084). The R-TME is safe and effective and has better postoperative short-term outcomes and faster intestinal function recovery time, contrasting with the L-TME. The large, multicenter, prospective studies were needed to validate the advantages of robotic surgery system used in rectal cancer.


Assuntos
Adenocarcinoma/cirurgia , Laparoscopia , Neoplasias Retais/cirurgia , Procedimentos Cirúrgicos Robóticos , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Tempo de Internação , Pessoa de Meia-Idade , Duração da Cirurgia , Recuperação de Função Fisiológica , Neoplasias Retais/patologia , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
9.
Asian J Surg ; 41(5): 401-416, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28912048

RESUMO

This meta-analysis aimed to investigate the effectiveness and safety of RAH and LLR for liver neoplasms. A systematic search was performed in PubMed, EMbase, the Cochrane Library, Web of science, and China Biology Medicine disc up to July 2016 for studies that provided comparisons between the surgical outcomes of RAH and LLR for liver neoplasms. WMD, OR and 95% CI were calculated and data combined using the random-effect model. The quality of the evidence was assessed using GRADE methods. A total of 17 studies were included in the meta-analysis, in which 487 patients were in the RAH group and 902 patients were in the LLR group. The meta-analysis results indicated: compared to LLR, RAH was associated with more estimated blood loss, longer operative time, and longer time to first nutritional intake (p < 0.05). There was no significant difference in length of hospital stay, conversion rate during operation, R0 resection rate, complications and mortality (p > 0.05). Three studies reported the total cost, and the result showed a higher cost in the RAH group when compared with the LLR group (p < 0.05). This meta-analysis indicated that RAH and LLR display similar effectiveness and safety in hepatectomy. Considering the lack of high quality original studies, prospective clinical trials should be conducted to provide strong evidence for clinical guidelines formation, and the insurance coverage policies should be established to promote the application of robotic surgery in the future.


Assuntos
Bases de Dados Bibliográficas , Hepatectomia/métodos , Laparoscopia , Neoplasias Hepáticas/cirurgia , Procedimentos Cirúrgicos Robóticos , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Humanos , Cobertura do Seguro , Laparoscopia/economia , Laparoscopia/mortalidade , Recidiva Local de Neoplasia/epidemiologia , Duração da Cirurgia , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/economia , Procedimentos Cirúrgicos Robóticos/mortalidade , Procedimentos Cirúrgicos Robóticos/tendências , Segurança , Fatores de Tempo , Resultado do Tratamento
10.
Medicine (Baltimore) ; 97(28): e11410, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29995787

RESUMO

BACKGROUND: Recently, in order to overcome the shortcomings of laparoscopic surgery in the treatment of low rectal cancer, a new kind of surgical procedure, transanal total mesorectal excision (TaTME), has rapidly become a research hotspot in the field of rectal cancer surgery study. Our study aimed to evaluate the efficacy and safety of transanal total mesorectal excision (TaTME) for the patients with rectal cancer. METHODS: Relevant studies were searched from the databases of the Cochrane Library, PubMed, Embase, Web of science. All relevant studies were collected to evaluate the efficacy and safety of TaTME for patients with rectal cancer. The quality of the included studies was assessed by the Newcastle-Ottawa Quality Assessment Scale (NOS) and Cochrane Library Handbook 5.1.0. Data analysis was conducted using the Review Manager 5.3 software. RESULTS: Thirteen studies including 859 patients were included in our analysis. In terms of efficacy, compared with laparoscopic total mesorectal excision (LaTME), meta-analysis showed that the rate of complete tumor resection increased and the risk of positive circumferential margins decreased in the TaTME group. For complete tumor resection and positive circumferential margins in the TaTME group, the odds ratios (ORs) and 95% confidence intervals (CIs) were 1.93 and 1.09 to 3.42 (P = .02) and 0.43 and 0.22 to 0.82 (P = .01), respectively. Concerning safety, results showed that the rates of postoperative complications were similar in the 2 groups, and differences in the risk of ileus and anastomotic leakage were not statistically significant (OR = 0.75, 95%CI = 0.51-1.09, P = .13; OR = 0.91, 95%CI = 0.46-1.78, P = .78; OR = 0.79, 95%CI = 0.45-1.38, P = .40). CONCLUSIONS: The results of this meta-analysis show that TaTME is associated with a reduced positive circumferential resection margin (CRM) rate, and could achieve complete tumor resection and improved the long-term survival in patients with mid- and low-rectal cancer.


Assuntos
Neoplasias Retais/cirurgia , Cirurgia Endoscópica Transanal/métodos , Humanos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Complicações Pós-Operatórias , Neoplasias Retais/patologia , Reto/patologia , Reto/cirurgia , Cirurgia Endoscópica Transanal/efeitos adversos
11.
Breast ; 40: 106-115, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29758503

RESUMO

BACKGROUND: Neoadjuvant chemotherapy (NAC) has become an essential treatment for breast cancer. However, there is still no consensus on the best tool to evaluate pathological response to NAC. METHODS: Two reviewers systematically searched Cochrane, PubMed, EMBASE, Web of Science, and CBM (last updated in February 2017) for eligible articles. We independently screened and selected studies that conformed to the inclusion criteria and extracted the requisite data. Pooled sensitivity, specificity, and the area under the SROC curve were calculated to estimate the diagnostic accuracy of magnetic resonance imaging (MRI) and positron emission computed tomography (PET/CT). And the relative DOR (RDOR) was used to compare accuracy for levels of the covariable. RESULTS: Thirteen studies involving 575 patients who underwent MRI and 618 who underwent PET/CT were included in our analysis. The pooled sensitivity and specificity of MRI were 0.88 (95% CI: 0.78-0.94) and 0.69 (95% CI: 0.51-0.83), respectively. The corresponding values for PET/CT were 0.77 (95% CI: 0.58-0.90) and 0.78 (95% CI: 0.63-0.88), respectively. The area under the SROC curve for MRI and PET/CT were 0.88 and 0.84, respectively. And the RDOR = 1.44 (95% CI, 0.46-4.47 P = 0.83). CONCLUSION: MRI had a higher sensitivity and PET/CT had a higher specificity in predicting the pathologic response after NAC in patients with breast cancer. According to the area under the SROC curve and anatomic discriminative resolution, MRI is the more suitable recommendation for predicting the pathologic response after NAC.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Imageamento por Ressonância Magnética/estatística & dados numéricos , Terapia Neoadjuvante/métodos , Avaliação de Resultados em Cuidados de Saúde/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/estatística & dados numéricos , Adulto , Idoso , Área Sob a Curva , Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Curva ROC , Sensibilidade e Especificidade , Resultado do Tratamento
12.
Medicine (Baltimore) ; 96(29): e7585, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28723798

RESUMO

BACKGROUND: The aim of this study was to assess the safety and effectiveness of robotic-assisted versus laparoscopic total mesorectal excision (TME) in patients with rectal cancer. METHODS: We systematically searched PubMed, EMBASE, Cochrane library, Web of science, and Chinese Biomedical Literature Database up to July 2016 to identify case-controlled studies that compared robotic TME (RTME) with laparoscopic TME (LTME) for rectal cancer. GRADE was used to interpret the primary outcomes of this meta-analysis. RESULTS: We included 17 case-control studies (3601 participants: 1726 underwent RTME and 1875 LTME for rectal cancer) that compared RTME with LTME for rectal cancer. We found no statistically significant differences between techniques for local recurrence [odds ratio (OR) = 0.68, P = .216] and overall survival at 3 years (OR = 0.71, P = 1.140), complications (OR = 1.02, P = .883), positive circumferential resection margin (PCRM) (OR = 0.80, P = .256), the first passing flatus [weighted mean difference (WMD) = -0.11, P = .130], reoperation (OR = 0.66, P = .080), estimated blood loss (EBL) (WMD = -12.45, P = .500), and length of stay in hospital (LOS) (WMD = -0.69, P = .089). Compared with LTME, RTME was associated with lower rate of conversion (OR = 0.35, P < .001), urinary retention (OR = 0.41, P = .025), and longer operative time (WMD = 57.43, P < .001). The overall quality of evidence was poor in all outcomes. CONCLUSION: RTME in patients with rectal cancer was associated with a lower rate of conversion and less incidence of urinary retention. Generally, operative time in RTME was significantly longer than in LTME. The long-term oncological and function outcomes of RTME seem to be equivalent with LTME. Therefore, analysis of current studies to date did not indicate a major benefit of RTME over LTME.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Laparoscopia , Neoplasias Retais/cirurgia , Procedimentos Cirúrgicos Robóticos , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Humanos , Laparoscopia/efeitos adversos , Procedimentos Cirúrgicos Robóticos/efeitos adversos
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