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1.
Chem Biodivers ; 19(7): e202200455, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35648483

RESUMO

Three new spiro-sesquiterpenoids, myrmekiones A-C (1-3), were isolated from the marine sponge Myrmekioderma sp. collected from the South China Sea. The structures of 1-3 were experimentally illuminated though comprehensive NMR spectra, X-ray diffraction analysis and calculated ECD. These three compounds possessed a special spiro skeleton. Compound 1 was characterized by a chamigrane-type structure, it is the first time to obtain the single-crystal of this type of oil compounds. 2 and 3 were a pair of diastereoisomers that possessed an acorane skeleton. This study expands the chemical diversity of marine origin spiro-metabolites.


Assuntos
Poríferos , Sesquiterpenos , Animais , China , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Poríferos/química , Sesquiterpenos/química
2.
Soft Matter ; 14(16): 3028-3039, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29637943

RESUMO

The diverse mechanical properties of nanoscale DNA films on solid substrates have a close correlation with complex detection signals of micro-/nano-devices. This paper is devoted to formulating several multiscale models to study the effect of pH-dependent ionic inhomogeneity on the graded elastic properties of nanoscale DNA films and the resultant bending deflections of microcantilever biosensors. First, a modified inverse Debye length is introduced to improve the classical Poisson-Boltzmann equation for the electrical potential of DNA films to consider the inhomogeneous effect of hydrogen ions. Second, the graded characteristics of the particle distribution are taken into consideration for an improvement in Parsegian's mesoscopic potential for both attraction-dominated and repulsion-dominated films. Third, by the improved interchain interaction potential and the thought experiment about the compression of a macroscopic continuum DNA bar, we investigate the diversity of the elastic properties of single-stranded DNA (ssDNA) films due to pH variations. The relevant theoretical predictions quantitatively or qualitatively agree well with the relevant DNA experiments on the electrical potential, film thickness, condensation force, elastic modulus, and microcantilever deflections. The competition between attraction and repulsion among the fixed charges and the free ions endows the DNA film with mechanical properties such as a remarkable size effect and a non-monotonic behavior, and a negative elastic modulus is first revealed in the attraction-dominated ssDNA film. There exists a transition between the pH-sensitive parameter interval and the pH-insensitive one for the bending signals of microcantilevers, which is predominated by the initial stress effect in the DNA film.


Assuntos
Técnicas Biossensoriais/métodos , DNA de Cadeia Simples/química , Elasticidade , Microtecnologia/instrumentação , Nanoestruturas/química , Concentração de Íons de Hidrogênio
3.
Medicine (Baltimore) ; 96(26): e7342, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28658150

RESUMO

BACKGROUND: The aim of this study was to evaluate the outcomes of patients with pathologic T0 esophageal carcinoma after neoadjuvant therapy and surgery. METHODS: We searched PubMed, Embase, Cochrane Library, and Medline databases from inception up to November 12, 2016. The meta-analysis was performed to compare odds ratios (OR) for overall survival (OS), disease-free survival (DFS), local control (LC), and distant control (DC). RESULTS: Eight published studies of 837 patients were included in the meta-analysis. Data showed that the ypT0N1 group was associated with worse outcomes compared with the ypT0N0 group. The pooled OR and 95% confidence interval (CI) for 3-year and 5-year OS were 3.08 [2.07, 4.57] and 4.27 [2.76, 6.59], respectively. Whereas, the pooled OR and 95% CI for 3-year and 5-year DFS were 3.90 [2.08, 7.34] and 5.17 [1.93, 13.87], respectively. The pooled OR and 95% CI for LR and DR were 4.52 [1.72, 11.91] and 2.65 [1.38, 5.09], respectively. CONCLUSIONS: Remnant lymph node metastases after neoadjuvant therapy and surgery in patients with pathologic T0 esophageal carcinoma portend poor survival, and it is an important prognostic factor.


Assuntos
Carcinoma/diagnóstico , Carcinoma/terapia , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/terapia , Metástase Linfática/diagnóstico , Humanos , Terapia Neoadjuvante , Prognóstico
4.
Neurosci Lett ; 633: 125-133, 2016 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-27651064

RESUMO

The alteration of pathological cortical surface may lead to the corresponding clinical manifestations of sporadic Parkinson's disease (sPD). Therefore, we investigated the correlates of cortical surface and clinical manifestations in the mid-stage sPD. Sixty seven mid-stage sPD patients and thirty five matched controls were performed the corticometry of magnetic resonance imaging (MRI) and the assessment of clinical manifestations including the demographic and disease-related characteristics, and underwent the final analysis of the correlates between cortical surface and clinical manifestations. The result revealed a significant correlation between CDT and Frontal-Sup-Orb-L, Frontal-Sup-Medial-L, Frontal-Mid-Orb-L and Rectus-L; SVFT and Frontal-Mid-L and Frontal-Inf-Tri-L; DF and Frontal-Sup-R, Frontal-Mid-R and Frontal-Sup-Medial-R; Webster and Occipital-Mid-R, Angular-R, Temporal-Sup-R and Temporal-Mid-R respectively in the mid-stage sPD patients. Our data suggested that the alterations of cortical surface in the left Frontal-Sup-Orb, Sup-Medial, Mid-Orb, Mid, Inf-Tri and Rectus, the right Frontal-Sup, Mid, Sup-Medial, and Occipital-Mid, Angular, Temporal-Sup and Temporal-Mid were the pathological base of some clinical manifestations including the cognitive impairment, the space structure, memory, attention, the abstract thinking, design, layout, utilization, digital, calculation, the time and spatial orientation concept, the operation sequence recognition and the partial motor dysfunctions in the mid-stage sPD, and that the dysfunctions of these brain regions contributed by the cortical surface lesion were closely correlated with some clinical manifestations of mid-stage sPD.


Assuntos
Córtex Cerebral/fisiopatologia , Doença de Parkinson/fisiopatologia , Idoso , Mapeamento Encefálico , Estudos de Casos e Controles , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/psicologia
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