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1.
J Am Chem Soc ; 145(47): 25545-25552, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37962982

RESUMO

Herein, we report a manganese-catalyzed three-component coupling of ß-H containing alcohols, methanol, and phosphines for the synthesis of γ-hydroxy phosphines via a borrowing hydrogen strategy. In this development, methanol serves as a sustainable C1 source. A variety of aromatic and aliphatic substituted alcohols and phosphines could undergo the dehydrogenative cross-coupling process efficiently and deliver the corresponding ß-phosphinomethylated alcohol products in moderate to good yields. Mechanistic studies suggest that this transformation proceeds in a sequential manner including catalytic dehydrogenation, aldol condensation, Michael addition, and catalytic hydrogenation.

2.
Angew Chem Int Ed Engl ; 62(26): e202303433, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37083026

RESUMO

A homogeneous manganese-catalyzed cross-coupling of two secondary alcohols for the divergent synthesis of γ-disubstituted alcohols and ß-disubstituted ketones is reported. Employing the well-defined Mn-MACHOPh as the catalyst, this novel protocol has a broad substrate scope with good functional group tolerance and affords a diverse library of valuable disubstituted alcohols and ketones in moderate to good yields. The strong influence of the reaction temperature on the selective formation of alcohol products was theorized in preliminary DFT studies. Studies have shown that the Gibbs free energy of the formation of alcohols is thermodynamically more favourable than corresponding ketones at a lower temperature.


Assuntos
Álcoois , Manganês , Cetonas , Oxirredução , Estrutura Molecular , Catálise
3.
Aesthetic Plast Surg ; 46(6): 2655-2664, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35237883

RESUMO

BACKGROUND: Gynecomastia (GYN) is the most common benign disease in males. A vacuum-assisted biopsy is a minimally invasive surgical technique for GYN treatment that achieves satisfactory aesthetic results. However, due to the operation under non-direct vision, it is difficult to localize the bleeding points and assess the residual glandular tissue. Endoscopy was applied to observe the operative field after subcutaneous mastectomy. The present study aimed to recommend our initial experience in glandular GYN with endoscope-assisted minimally invasive subcutaneous mastectomy. METHODS: A total of 34 patients diagnosed with glandular GYN (50 breasts), treated with endoscope-assisted minimally invasive surgery at The First Affiliated Hospital with Nanjing Medical University between June 2018 and June 2020, were enrolled in this study. According to Simon's classification of the breast, 10 was grade I, 25 was grade IIA, and 15 was grade IIB. The characteristics of patients, operative data, postoperative complications, cosmetic outcome, and patient satisfaction were recorded. RESULTS: Endoscope-assisted minimally invasive mastectomy was performed successfully in all cases. The operative duration of the operation was 55-120 min/side. The total weight of the resected tissue of the 50 breasts was 55-350 g, and the blood loss was 10-105 mL/breast. Endoscopy detected five breasts with bleeding and three with residual glandular during the operation. Postoperative bleeding occurred in 1 breast, subcutaneous seroma in 3 breasts, dysesthesia of the nipple-areolar complex in 2 breasts, and skin redundancy in a bilateral patient. None of the patients experienced severe pain, infection, nipple necrosis, and nipple retraction, a saucer-like deformity. With a median follow-up of 21 months, all patients were satisfied with their cosmetic outcome (100%), and no recurrence occurred. CONCLUSION: Endoscope-assisted minimally invasive mastectomy could be used as a feasible technique for the treatment of glandular GYN. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online. Instructions to Authors www.springer.com/00266 .


Assuntos
Neoplasias da Mama , Humanos , Feminino , Mastectomia , Procedimentos Cirúrgicos Minimamente Invasivos
5.
Environ Manage ; 53(6): 1066-76, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24696037

RESUMO

Land use and ecosystem services need to be assessed simultaneously to better understand the relevant factors in sustainable land management. This paper analyzed land use changes in the middle reach of the arid Heihe River Basin in northwest China over the last two decades and their impacts on water resources and soil organic carbon (SOC) storage. The results indicated that from 1986 to 2007: (1) cropland and human settlements expanded by 45.0 and 17.6%, respectively, at the expense of 70.1, 35.7, and 4.1% shrinkage on woodland, grassland, and semi-shrubby desert; (2) irrigation water use was dominant and increased (with fluctuations) at an average rate of 8.2%, while basic human water consumption increased monotonically over a longer period from 1981 to 2011 at a rate of 58%; and (3) cropland expansion or continuous cultivation led to a significant reduction of SOC, while the land use transition from grassland to semi-shrubby desert and the progressive succession of natural ecosystems such as semi-shrubby desert and grassland, in contrast, can bring about significant carbon sequestration benefits. The increased water consumption and decreased SOC pool associated with some observed land use changes may induce and aggravate potential ecological risks for both local and downstream ecosystems, including water resource shortages, soil quality declines, and degeneration of natural vegetation. Therefore, it is necessary to balance socioeconomic wellbeing and ecosystem services in land use planning and management for the sustainability of socio-ecological systems across spatiotemporal scales, especially in resource-poor arid environments.


Assuntos
Sequestro de Carbono , Carbono/química , Solo/química , Água , Irrigação Agrícola , Carbono/análise , China , Ingestão de Líquidos , Ecossistema , Humanos , Rios
6.
Cancer Med ; 12(7): 8815-8824, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36734288

RESUMO

BACKGROUND: Multifocal (MF) and multicentric (MC) breast cancer cases have been increasingly diagnosed owing to the extensive use of improved preoperative breast imaging. The current tumor-node-metastasis staging system uses the dimension of the largest tumor and recommends reporting the pathological features of the largest tumor in MF/MC breast cancers. AIM: This study aimed to explore whether the largest or aggregate dimensions of MF and MC breast cancers can better predict tumor behavior. We also attempted to study the histological and biological heterogeneities of separate foci in MF and MC breast cancers to determine whether it was necessary to examine each lesion. METHODS: We retrospectively analyzed 121 patients with MF/MC (103 with MF and 18 with MC) breast cancers and 484 patients with unifocal breast cancer who were treated at the First Affiliated Hospital of Nanjing Medical University. Two methods were used to record the T stage (using the dimensions of the largest lesion and aggregate dimensions of all lesions). The histological grade, immunohistochemical parameters, and molecular subtypes of the largest lesion and other lesions in MF/MC breast cancers were studied to assess intertumoral heterogeneity. RESULTS: The use of aggregate dimensions upstaged 63 patients with MF/MC breast cancers to a more advanced stage and removed the independent effect of cancer multiplicity on lymph node positivity compared with the use of the largest dimension. Mismatches were found in the pathological type (9.9%), histological grade (4.1%), and molecular subtype (8.3%) among different foci. CONCLUSION: The tendency of MF/MC breast tumors to metastasize may be related to tumor load, which can be better predicted by the aggregate dimensions of all foci. The use of the current staging systems may require further evaluation and modification. Intertumoral heterogeneity indicates the necessity for pathological and immunohistochemical assessments of each lesion in patients with MF/MC breast cancers.


Assuntos
Neoplasias da Mama , Segunda Neoplasia Primária , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/química , Estudos Retrospectivos , Estadiamento de Neoplasias , Recidiva Local de Neoplasia/patologia , Segunda Neoplasia Primária/patologia
7.
Front Cell Neurosci ; 13: 145, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31031600

RESUMO

Epilepsy is a disorder of abnormal brain activity typified by spontaneous and recurrent seizures. MicroRNAs (miRNAs) are short non-coding RNAs, critical for the post-transcriptional regulation of gene expression. MiRNA dysregulation has previously been implicated in the induction of epilepsy. In this study, we examined the effect of silencing miR-134 against status epilepticus (SE). Our results showed that level of miR-134 was significantly up-regulated in rat brain after Kainic acid (KA)-induced SE. TUNEL staining showed that silencing miR-134 alleviated seizure-induced neuronal apoptosis in the CA3 subfield of the hippocampus. Western blot showed that a miR-134 antagonist suppressed lesion-induced endoplasmic reticulum (ER) stress and apoptosis related expression of CHOP, Bim and Cytochrome C, while facilitated the expression of CREB at 24 h post KA-induced lesion in the hippocampus. Consistently, silencing miR-134 significantly diminished loss of CA3 pyramidal neurons using Nissl staining as well as reducing aberrant mossy fiber sprouting (MFS) in a rat epileptic model. In addition, the results of EEG and behavior analyses showed seizures were alleviated by miR-134 antagonist in our experimental models. These results suggest that silencing miR-134 modulates the epileptic phenotype by upregulating its target gene, CREB. This in turn attenuates oxidative and ER stress, inhibits apoptosis, and decreases MFS long term. This indicates that silencing miR-134 might be a promising intervention for the treatment of epilepsy.

8.
Environ Sci Pollut Res Int ; 22(24): 20226-33, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26527336

RESUMO

Nitrate contamination in surface water has become an environmental problem widespread concern. In this study, environmental isotopes (δ(15)N-NO3 (-) and δ(18)O-NO3 (-)) and the chemical compositions of water samples from an urban river in Chongqing, China, were analyzed to evaluate the primary sources of nitrate pollution. A Bayesian isotope mixing model was applied to estimate the relative contributions of five potential NO3 (-) sources to river pollution (sewage/manure, soil N, NH4 (+) in fertilizer and precipitation, NO3 (-) fertilizer, and NO3 (-) in precipitation). The results show that the urban river was affected by NO3 (-) pollution from multiple sources. The major sources of NO3 (-) pollution in the dry season were sewage/manure (38-50 %) and soil N (22-26 %); in the wet season, the major sources of NO3 (-) pollution were sewage/manure (30-37 %), soil N (16-25 %), and precipitation (14-24 %). The higher contribution of N to the river water by precipitation indicates that atmospheric N deposition has become an important source of pollution in surface water in China. We conclude that domestic sewage is still the main contributor to NO3 (-) pollution in urban rivers in China. The discharge of domestic sewage into rivers should be prohibited as a priority measure to prevent NO3 (-) contamination.


Assuntos
Monitoramento Ambiental/métodos , Modelos Teóricos , Nitratos/análise , Rios/química , Urbanização , Poluentes Químicos da Água/análise , Teorema de Bayes , China , Análise por Conglomerados , Fertilizantes , Esterco , Isótopos de Nitrogênio/análise , Isótopos de Oxigênio/análise , Estações do Ano , Esgotos
9.
PLoS One ; 8(1): e54660, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23372749

RESUMO

Many spatial interpolation methods perform well for gentle terrains when producing spatially continuous surfaces based on ground point data. However, few interpolation methods perform satisfactorily for complex terrains. Our objective in the present study was to analyze the suitability of several popular interpolation methods for complex terrains and propose an optimal method. A data set of 153 soil water profiles (1 m) from the semiarid hilly gully Loess Plateau of China was used, generated under a wide range of land use types, vegetation types and topographic positions. Four spatial interpolation methods, including ordinary kriging, inverse distance weighting, linear regression and regression kriging were used for modeling, randomly partitioning the data set into 2/3 for model fit and 1/3 for independent testing. The performance of each method was assessed quantitatively in terms of mean-absolute-percentage-error, root-mean-square-error, and goodness-of-prediction statistic. The results showed that the prediction accuracy differed significantly between each method in complex terrain. The ordinary kriging and inverse distance weighted methods performed poorly due to the poor spatial autocorrelation of soil moisture at small catchment scale with complex terrain, where the environmental impact factors were discontinuous in space. The linear regression model was much more suitable to the complex terrain than the former two distance-based methods, but the predicted soil moisture changed too sharply near the boundary of the land use types and junction of the sunny (southern) and shady (northern) slopes, which was inconsistent with reality because soil moisture should change gradually in short distance due to its mobility in soil. The most optimal interpolation method in this study for the complex terrain was the hybrid regression kriging, which produced a detailed, reasonable prediction map with better accuracy and prediction effectiveness.


Assuntos
Solo/análise , Água/química , China , Monitoramento Ambiental , Reprodutibilidade dos Testes , Análise Espacial
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