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1.
Anal Chim Acta ; 1189: 339208, 2022 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-34815044

RESUMO

The electrochemical method for highly sensitive determination of arsenic(III) in real water samples with noble-metal-free nanomaterials is still a difficult but significant task. Here, an electrochemical sensor driven by noble-metal-free layered porous Fe3O4/Co3S4 nanosheets was successfully employed for As(III) analysis, which was prepared via a facile two-step method involves a hydrothermal treatment and a subsequent sulfurization process. As expected, the electrochemical detection of As(III) in 0.1 M HAc-NaAc (pH 6.0) by square wave anodic stripping voltammetry (SWASV) with a considerable sensitivity of 4.359 µA/µg·L-1 was obtained, which is better than the commonly used noble metals modified electrodes. Experimental and characterization results elucidate the enhancement of As(III) electrochemical performance could be attributed to its nano-porous structure, the presence of oxygen vacancies and strong synergetic coupling effects between Fe3O4 and Co3S4 species. Besides, the Fe3O4/Co3S4 modified screen printed carbon electrode (Fe3O4/Co3S4-SPCE) shows remarkable stability and repeatability, valuable anti-interference ability and could be used for detection in real water samples. Consequently, the results confirm that as-prepared porous Fe3O4/Co3S4 nanosheets is identified as a promising modifier to detect As(III) in real sample analysis.


Assuntos
Técnicas Eletroquímicas , Oxigênio , Carbono , Eletrodos , Ouro
2.
J Pharm Biomed Anal ; 208: 114471, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34814080

RESUMO

Yunaconitine (YAC), crassicauline A (CCA), 8-deacetylyunaconitine (DYA), and 8-deacetylcrassicauline A (DCA), as hidden toxic Aconitum alkaloids, are detected in some products of processed Aconitum carmichaelii lateral root and poisoning cases. The distribution and toxicity of these four components in Aconitum herbs should be further systematically studied for medication safety. This study developed a new UHPLC-QQQ-MS/MS method to determine ten Aconitum alkaloids, including aconitine, mesaconitine, hypaconitine, benzoylaconine, benzoylmesaconine, benzoylhypaconine, YAC, CCA, DYA, and DCA, for Aconitum herbs simultaneously. YAC and CCA were founded in some samples of unprocessed A. carmichaelii lateral root (7.04%), A. carmichaelii root (9.43%), A. brachypodum root (6.00%), and A. ouvrardianum root (100%). Four hidden toxic Aconitum alkaloids were detected in processed A. carmichaelii lateral root (2.56%) and A. vilmorinianum root (100%). Four hidden toxic Aconitum alkaloids played significant roles in the classification of Aconitum herbs by OPLS-DA analysis. The acute toxicity test was performed by up-and-down procedure (UDP). The oral administration of the half lethal dose (LD50) of YAC, CCA, DYA, and DCA to female ICR mice was 2.37 mg/kg, 5.60 mg/kg, 60.0 mg/kg, and 753 mg/kg, respectively. The LD50 by intravenous injection was 0.200 mg/kg, 0.980 mg/kg, 7.60 mg/kg, and 34.0 mg/kg, respectively. The LD50 of unprocessed A. carmichaelii lateral root, A. vilmorinianum root, and A. brachypodum root to mice orally was 1.89 g/kg, 0.950 g/kg, and 0.380 g/kg, respectively. Symptoms of Aconitum alkaloid poisoning in mice were decreased activity, fur erect, palpebral edema, vomiting, polypnea, and convulsions. The main change of organs was flatulence. No poisoning or death occurred in mice at the maximum dosage (27.0 g/kg) of A. ouvrardianum root orally. To better control the quality and safety of Aconitum herbs, this study provides favorable support for improving the existing standards to strengthen the supervision of the four hidden toxic Aconitum alkaloids.

3.
Neural Regen Res ; 17(5): 1106-1114, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34558539

RESUMO

Although autologous nerve transplantation is the gold standard for treating peripheral nerve defects, it has many clinical limitations. As an alternative, various tissue-engineered nerve grafts have been developed to substitute for autologous nerves. In this study, a novel nerve graft composed of chitin scaffolds and a small autologous nerve was used to repair sciatic nerve defects in rats. The novel nerve graft greatly facilitated regeneration of the sciatic nerve and myelin sheath, reduced atrophy of the target muscle, and effectively restored neurological function. When the epineurium of the small autogenous nerve was removed, the degree of nerve regeneration was similar to that which occurs after autogenous nerve transplantation. These findings suggest that our novel nerve graft might eventually be a new option for the construction of tissue-engineered nerve scaffolds. The study was approved by the Research Ethics Committee of Peking University People's Hospital (approval No. 2019PHE27) on October 18, 2019.

4.
Neural Regen Res ; 17(2): 418-426, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34269218

RESUMO

Lower extremity nerve transposition repair has become an important treatment strategy for peripheral nerve injury; however, brain changes caused by this surgical procedure remain unclear. In this study, the distal stump of the right sciatic nerve in a rat model of sciatic nerve injury was connected to the proximal end of the left sciatic nerve using a chitin conduit. Neuroelectrophysiological test showed that the right lower limb displayed nerve conduction, and the structure of myelinated nerve fibers recovered greatly. Muscle wet weight of the anterior tibialis and gastrocnemius recovered as well. Multiple-model resting-state blood oxygenation level-dependent functional magnetic resonance imaging analysis revealed functional remodeling in multiple brain regions and the re-establishment of motor and sensory functions through a new reflex arc. These findings suggest that sciatic nerve transposition repair induces brain functional remodeling. The study was approved by the Ethics Committee of Peking University People's Hospital on December 9, 2015 (approval No. 2015-50).

5.
Carbohydr Polym ; 275: 118697, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34742424

RESUMO

Ionic conductive hydrogels have been widely applied in sensors, energy storage and soft electronics recently. However, most of the polyvinyl alcohol (PVA) based ionic hydrogels are mainly fabricated by soaking the hydrogels in high concentration electrolyte solution which can induce the waste of electrolyte and solvent. Herein, we have designed cellulose nanofibrils (CNF) and ZnSO4 reinforced PVA based hydrogels through a one-pot simple freezing-thawing method at low ZnSO4 concentration without any soaking process. Furthermore, the hydrogel with 0.4% CNF exhibited stress up to 0.79 MPa (242% strain) and high ionic conductivity of 0.32 S m-1 (0.07 M ZnSO4). Moreover, hydrogel sensor displayed high linear gauge factor 1.70 (0-200% strain), excellent stability, durability and reliability. The integrated hydrogel sensor also showed excellent sensor performance for human motion monitoring. This work provides a new prospect for the design of cellulose reinforced conductive hydrogels via a facile method.

6.
Hortic Res ; 8(1): 255, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34848682

RESUMO

The marvelously diverse Orchidaceae constitutes the largest family of angiosperms. The genus Cymbidium in Orchidaceae is well known for its unique vegetation, floral morphology, and flower scent traits. Here, a chromosome-scale assembly of the genome of Cymbidium ensifolium (Jianlan) is presented. Comparative genomic analysis showed that C. ensifolium has experienced two whole-genome duplication (WGD) events, the most recent of which was shared by all orchids, while the older event was the τ event shared by most monocots. The results of MADS-box genes analysis provided support for establishing a unique gene model of orchid flower development regulation, and flower shape mutations in C. ensifolium were shown to be associated with the abnormal expression of MADS-box genes. The most abundant floral scent components identified included methyl jasmonate, acacia alcohol and linalool, and the genes involved in the floral scent component network of C. ensifolium were determined. Furthermore, the decreased expression of photosynthesis-antennae and photosynthesis metabolic pathway genes in leaves was shown to result in colorful striped leaves, while the increased expression of MADS-box genes in leaves led to perianth-like leaves. Our results provide fundamental insights into orchid evolution and diversification.

7.
Artigo em Inglês | MEDLINE | ID: mdl-34856890

RESUMO

The use of multi-modal approaches, particularly in conjunction with multivariate analytic techniques, can enrich models of cognition, brain function, and how they change with age. Recently, multivariate approaches have been applied to the study of eye movements in a manner akin to that of neural activity (i.e., pattern similarity). Here, we review the literature regarding multi-modal and/or multivariate approaches, with specific reference to the use of eyetracking to characterize age-related changes in memory. By applying multi-modal and multivariate approaches to the study of aging, research has shown that aging is characterized by moment-to-moment alterations in the amount and pattern of visual exploration, and by extension, alterations in the activity and function of the hippocampus and broader medial temporal lobe (MTL). These methodological advances suggest that age-related declines in the integrity of the memory system has consequences for oculomotor behavior in the moment, in a reciprocal fashion. Age-related changes in hippocampal and MTL structure and function may lead to an increase in, and change in the patterns of, visual exploration in an effort to upregulate the encoding of information. However, such visual exploration patterns may be non-optimal and actually reduce the amount and/or type of incoming information that is bound into a lasting memory representation. This research indicates that age-related cognitive impairments are considerably broader in scope than previously realized.

8.
J Agric Food Chem ; 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34752089

RESUMO

Fu brick tea (FBT) is a microbial-fermented tea, which is produced by the solid-state fermentation of tea leaves. Previous studies have proved that FBT aqueous extracts could attenuate obesity and gut microbiota dysbiosis. However, the bioactive components in FBT that contribute to these activities remain unclear. In this study, we aimed to investigate the effects of FBT polyphenols (FBTPs) on obesity, gut microbiota, and gut microbiota-related intestinal oxidative stress and barrier function and to further investigate whether the antiobesity effect of FBTPs was dependent on the alteration of gut microbiota. The results showed that FBTP supplementation effectively attenuated obesity in high-fat diet (HFD)-fed rats. FBTP supplementation improved the intestinal oxidative stress and intestinal barrier function, including intestinal inflammation and the integrity of the intestinal barrier. Furthermore, FBTP intervention significantly attenuated HFD-induced gut microbiota dysbiosis, characterized by increased phylogenetic diversity and decreased Firmicutes/Bacteroidetes ratio. Certain core microbes, including Akkermansia muciniphila, Alloprevotella, Bacteroides, and Faecalibaculum, were also found to be improved by FBTPs. Moreover, the antiobesity effect of FBTPs was gut microbiota-dependent, as demonstrated by a fecal microbiota transplantation experiment. Collectively, we concluded that FBTPs reduced obesity by modulating the gut microbiota and gut microbiota-related intestinal oxidative stress and barrier function. Therefore, FBTPs may be used as prebiotic agents to treat obesity and gut microbiota dysbiosis in obese individuals.

9.
Acta Pharmacol Sin ; 2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34845369

RESUMO

Ras has long been viewed as a promising target for cancer therapy. Farnesylthiosalicylic acid (FTS), as the only Ras inhibitor has ever entered phase II clinical trials, has yielded disappointing results due to its strong hydrophobicity, poor tumor-targeting capacity, and low therapeutic efficiency. Thus, enhancing hydrophilicity and tumor-targeting capacity of FTS for improving its therapeutic efficacy is of great significance. In this study we conjugated FTS with a cancer-targeting small molecule dye IR783 and characterized the anticancer properties of the conjugate FTS-IR783. We showed that IR783 conjugation greatly improved the hydrophilicity, tumor-targeting and therapeutic potential of FTS. After a single oral administration in Balb/c mice, the relative bioavailability of FTS-IR783 was increased by 90.7% compared with FTS. We demonstrated that organic anion transporting polypeptide (OATP) and endocytosis synergistically drove the uptake of the FTS-IR783 conjugate in breast cancer MDA-MB-231 cells, resulting in superior tumor-targeting ability of the conjugate both in vitro and in vivo. We further revealed that FTS-IR783 conjugate could bind with and directly activate AMPK rather than affecting Ras, and subsequently regulate the TSC2/mTOR signaling pathway, thus achieving 2-10-fold increased anti-cancer therapeutic efficacy against 6 human breast cancer cell lines compared to FTS both in vivo and in vitro. Overall, our data highlights a promising approach for the modification of the anti-tumor drug FTS using IR783 and makes it possible to return FTS back to the clinic with a better efficacy.

10.
Zhongguo Gu Shang ; 34(11): 1087-90, 2021 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-34812030

RESUMO

Full endoscopic transforaminal lumbar interbody fusion has been used widely in the field of minimally invasive spine surgery in recent years. This paper briefly introduces the development history, technical points, indications, curative effects and complications. Authors believe that the full endoscopic transforaminal lumbar interbody fusion has the same clinical effects as traditional surgery, and can effectively reduce tissue damage and intraoperative bleeding, reduce the incidence of postoperative low back pain, shorten the time to get out of bed, and reduce the average hospitalization time. However, it is still necessary to improve the long-term follow up in order to further evaluate the effectiveness and safety of the procedure.


Assuntos
Fusão Vertebral , Endoscopia , Humanos , Vértebras Lombares/cirurgia , Região Lombossacral , Procedimentos Cirúrgicos Minimamente Invasivos , Estudos Retrospectivos , Resultado do Tratamento
12.
Diabetes Res Clin Pract ; 183: 109126, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34742784

RESUMO

AIMS: We focused on BMSC-derived exosomal lncRNA KLF3-AS1 and its significance in diabetic cutaneous wound healing. METHODS: Potential interaction between KLF3-AS1 and miR-383, miR-383 and VEGFA were predicted using bioinformatic analysis and validated by luciferase reporter, RIP, and FISH assays. The proliferation, apoptosis, migration and tube formation of HUVECs were evaluated by CCK-8, flow cytometry, wound healing, and tube formation assays, respectively. A murine diabetic cutaneous wound model was used to investigate therapeutic effects of exosomal KLF3-AS1 in vivo. Histological alterations in skin tissues were examined using HE, Masson staining, and immunostaining of CD31. RESULTS: BMSC-derived exosomal KLF3-AS1 sufficiently promoted proliferation, migration, and tube formation, while inhibited apoptosis of HUVECs challenged by high glucose. The protective effects of exosomal KLF3-AS1 were achieved at least partially by down-regulating miR-383, and boosting the expression of its target, VEGFA. In vivo, exosomes from KLF3-AS1-expressing BMSCs demonstrated the best effects in promoting cutaneous wound healing in diabetic mice, which were associated with minimal weight loss, increased blood vessel formation, reduced inflammation, decreased miR-383 expression, and up-regulated VEGFA. CONCLUSIONS: Exosomal lncRNA KLF3-AS1 derived from BMSCs induces angiogenesis to promote diabetic cutaneous wound healing.

13.
Mol Phylogenet Evol ; 167: 107362, 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34775057

RESUMO

Delimitation of the tribe Arethuseae has varied considerably since it was first defined. The relationships within Arethuseae, particularly within the subtribe Arethusinae, remain poorly elucidated. In this study, we reconstructed the phylogeny of Arethuseae, using six plastid markers (matK, ycf1, rbcL rpoc1, rpl32-trnL and trnL-F) from 83 taxa. The ancestral state reconstruction of 11 selected morphological characters was also conducted to identify synapomorphies and assess potential evolutionary transitions. Morphological character comparision between the distinct species Bletilla foliosa and other species are conducted. Our results unequivocally supported the monophyly of Arethuseae, which included highly supported clades and a clear synapomorphy of non-trichome-like lamellae. Furthermore, B. foliosa formed a separate clade in the subtribe Arethusinae, instead of clustering with the other Bletilla species in the subtribe Coelogyninae. The morphological characters comparision further showed that the B. foliosa clade could be distinguished from other genera in Arethuseae by multiple characters, including presence of lateral inflorescence, three lamellae with trichome-like apex and four pollinia. In light of these molecular and morphological evidences, we propose Mengzia as a new genus to accommodate B. foliosa and accordingly provide descriptions of this new genus and combination.

14.
Pharmacol Res ; 175: 105977, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34798265

RESUMO

Inflammation is closely linked to the abnormal phospholipid metabolism chain of cyclooxygenase-2/microsomal prostaglandin E2 synthase-1/prostaglandin E2 (COX-2/mPGES-1/PGE2). In clinical practice, non-steroidal anti-inflammatory drugs (NSAIDs) as upstream COX-2 enzyme activity inhibitors are widely used to block COX-2 cascade to relieve inflammatory response. However, NSAIDs could also cause cardiovascular and gastrointestinal side effects due to its inhibition on other prostaglandins generation. To avoid this, targeting downstream mPGES-1 instead of upstream COX is preferable to selectively block overexpressed PGE2 in inflammatory diseases. Some mPGES-1 inhibitor candidates including synthetic compounds, natural products and existing anti-inflammatory drugs have been proved to be effective in in vitro experiments. After 20 years of in-depth research on mPGES-1 and its inhibitors, ISC 27864 have completed phase II clinical trial. In this review, we intend to summarize mPGES-1 inhibitors focused on their inhibitory specificity with perspectives for future drug development.

15.
J Genet Genomics ; 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34757038

RESUMO

Melastomataceae have abundant morphological diversity with high economic and ornamental merit in Myrtales. The phylogenetic position of Myrtales is still contested. Here, we report the first chromosome-level genome assembly of Melastoma dodecandrum in Melastomataceae. The assembled genome size was 299.81 Mb with a contig N50 value of 3.00 Mb. Genome evolution analysis indicated that M. dodecandrum, Eucalyptus grandis and Punica granatum were clustered into a clade of Myrtales and formed a sister group with the ancestor of fabids and malvids. We found that M. dodecandrum experienced four whole-genome polyploidization events: the ancient event was shared with most eudicots, one event was shared with Myrtales, and the other two events were unique to M. dodecandrum. Moreover, we identified MADS-box genes and found that the AP1-like genes expanded, and AP3-like genes might have undergone subfunctionalization. We found that the SUAR63-like genes and AG-like genes showed different expression patterns in stamens, which may be associated with heteranthery. In addition, we found that LAZY1-like genes were involved in the negative regulation of stem branching development, which may be related to its creeping features. Our study sheds new light on the evolution of Melastomataceae and Myrtales, which provides a comprehensive genetic resource for future research.

17.
Int J Biol Macromol ; 193(Pt A): 64-70, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34688675

RESUMO

Pure deep eutectic solvents (DESs) system of choline chloride (ChCl)/Lactic acid (Lac) were demonstrated to be an effective strategy for extraction of lignin. In this study, two kinds of different promising solid acid (SA) with DESs were designed to promote the pretreatment of lignocellulose. The SA of phosphotungstic acid (H3O40PW12) and iron bromide (FeBr3) were introduced into DESs to extract poplar wood lignin and evaluate the antioxidant activity. It was found that 82.2% and 80.9% of lignin were obtained from poplar wood under H3O40PW12-ChCl/Lac acid and FeBr3-choline ChCl/Lac system with 4 h and 8 h, respectively. The lignin fractions with a high purity (>89%), low molecular weight (Mw 1800-2000 g/mol). Besides, the antioxidant activities of lignin fractions were better than butyl hydroxyanisole (BHA). Therefore, DES lignin has prominent antioxidant activity and could developed a potential natural cosmetics and food packaging.

18.
Transl Psychiatry ; 11(1): 499, 2021 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-34593760

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic has caused large-scale economic and social losses and worldwide deaths. Although most COVID-19 patients have initially complained of respiratory insufficiency, the presence of neuropsychiatric manifestations is also reported frequently, ranging from headache, hyposmia/anosmia, and neuromuscular dysfunction to stroke, seizure, encephalopathy, altered mental status, and psychiatric disorders, both in the acute phase and in the long term. These neuropsychiatric complications have emerged as a potential indicator of worsened clinical outcomes and poor prognosis, thus contributing to mortality in COVID-19 patients. Their etiology remains largely unclear and probably involves multiple neuroinvasive pathways. Here, we summarize recent animal and human studies for neurotrophic properties of severe acute respiratory syndrome coronavirus (SARS-CoV-2) and elucidate potential neuropathogenic mechanisms involved in the viral invasion of the central nervous system as a cause for brain damage and neurological impairments. We then discuss the potential therapeutic strategy for intervening and preventing neuropsychiatric complications associated with SARS-CoV-2 infection. Time-series monitoring of clinical-neurochemical-radiological progress of neuropsychiatric and neuroimmune complications need implementation in individuals exposed to SARS-CoV-2. The development of a screening, intervention, and therapeutic framework to prevent and reduce neuropsychiatric sequela is urgently needed and crucial for the short- and long-term recovery of COVID-19 patients.


Assuntos
COVID-19 , Animais , Cefaleia , Humanos , Pandemias , SARS-CoV-2 , Convulsões
19.
Hortic Res ; 8(1): 215, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34593777

RESUMO

The genetic diversity of germplasm is critical for exploring genetic and phenotypic resources and has important implications for crop-breeding sustainability and improvement. However, little is known about the factors that shape and maintain genetic diversity. Here, we assembled a high-quality chromosome-level reference of the Chinese common apricot 'Yinxiangbai', and we resequenced 180 apricot accessions that cover four major ecogeographical groups in China and other accessions from occidental countries. We concluded that Chinese-cultivated common apricot germplasms possessed much higher genetic diversity than those cultivated in Western countries. We also detected seven migration events among different apricot groups, where 27% of the genome was identified as being introgressed. Remarkably, we demonstrated that these introgressed regions drove the current high level of germplasm diversity in Chinese-cultivated common apricots by introducing different genes related to distinct phenotypes from different cultivated groups. Our results highlight the consideration that introgressed regions may provide an important reservoir of genetic resources that can be used to sustain modern breeding programs.

20.
Neoplasma ; 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34641698

RESUMO

Bladder cancer is a common malignant tumor with a high recurrence rate and mortality, while the detailed mechanisms for bladder cancer progression and metastasis are unknown. Recently, long non-coding RNAs (lncRNAs) are reported to be involved in the development of cancers. In this study, we aim to investigate the role of lncRNA LINC00355 in bladder cancer progression and metastasis. The association between LINC00355 and the prognosis of bladder cancer patients was determined by Kaplan-Meier survival analysis. Cell migration and invasion ability were detected using the Transwell migration and invasion assay. The relationships of LINC00355, miR-424-5p, and High Mobility Group AT-Hook 2 (HMGA2) were verified through the luciferase assay and RNA pull-down assay. Xenograft tumor was established to evaluated tumor lung metastasis in vivo. qRT-PCR and western blot were used to detect gene expression. LINC00355 was upregulated in bladder cancer patients, especially in patients with higher TNM stage. Elevated LINC00355 was correlated with the poor prognosis of bladder cancer patients. Besides, overexpressed LINC00355 promoted migration, invasion, and epithelial-mesenchymal transition (EMT) ability of bladder cancer cells. Contrarily, decreased LINC00355 suppressed migration, invasion, and EMT ability of bladder cancer cells and lung metastasis of xenograft tumors. Furthermore, LINC00355 could regulate HMGA2 expression by acting as a sponge for miR-424-5p. Overexpression of HMGA2 induced EMT of bladder cancer cells. Additionally, LINC00355 regulated the migration, invasion, and EMT ability of bladder cancer cells through modulating HMGA2 expression via sponging miR-424-5p. LINC00355 promoted migration, invasion, and EMT ability of bladder cancer through elevating HMGA2 expression via acting as a sponge for miR-424-5p.

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