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1.
Chemosphere ; 282: 131110, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34470162

RESUMO

Fibrous activated carbon has attracted emerging research interests due to its remarkable adsorption performance for volatile organic compounds (VOCs). Though this adsorption behavior for VOCs is closely related to the pore structure on the surface of activated carbon fiber (ACF), few researchers paid attentions to the influence of textural properties of this adsorption process. Especially, cotton-based activated carbon fiber (CACF) for adsorbing benzene pollutant is rarely reported. Herein, in order to develop a high-performance adsorbent for the removal of VOCs pollutants, this work studied the influence of textural properties of CACF on the adsorption of benzene. The results showed that the increase of carbonization temperature would lead to the reduction of mesopores but the increase of micropores for CACF; the embedment of phosphoric acid and its derivatives into the carbon layers contributed to the formation of pore structure for CACF; furthermore, specific surface area of CACF can also be enlarged by increasing the concentration of phosphoric acid. More importantly, it was found that the adsorption capacity of CACF for benzene was strongly dependent on the specific surface area and volume of micropores within CACF because micropores can provide more favorable binding sites. This adsorption process preferred to occur on the wall of micropores, then the accumulated benzene would slowly fill the pores. Interestingly, the decrease of pore size of micropores can unexpectedly improve the affinity of CACF to benzene on the contrary. This work provides a new strategy to develop porous structured ACF materials for the high-performance adsorption of VOCs.


Assuntos
Benzeno , Carvão Vegetal , Adsorção , Fibra de Carbono , Porosidade
2.
Cell Prolif ; 54(6): e13042, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33955094

RESUMO

OBJECTIVES: The effects of general anaesthetics on fetal brain development remain elusive. Radial glial progenitors (RGPs) generate the majority of neurons in developing brains. Here, we evaluated the acute alterations in RGPs after maternal sevoflurane exposure. METHODS: Pregnant mice were exposed to 2.5% sevoflurane for 6 hours on gestational day 14.5. Interkinetic nuclear migration (INM) of RGPs in the ventricular zone (VZ) of the fetal brain was evaluated by thymidine analogues labelling. Cell fate of RGP progeny was determined by immunostaining using various neural markers. The Morris water maze (MWM) was used to assess the neurocognitive behaviours of the offspring. RNA sequencing (RNA-Seq) was performed for the potential mechanism, and the potential mechanism validated by quantitative real-time PCR (qPCR), Western blot and rescue experiments. Furthermore, INM was examined in human embryonic stem cell (hESC)-derived 3D cerebral organoids. RESULTS: Maternal sevoflurane exposure induced temporary abnormities in INM, and disturbed the cell cycle progression of RGPs in both rodents and cerebral organoids without cell fate alternation. RNA-Seq analysis, qPCR and Western blot showed that the Notch signalling pathway was a potential downstream target. Reactivation of Notch by Jag1 and NICD overexpression rescued the defects in INM. Young adult offspring showed no obvious cognitive impairments in MWM. CONCLUSIONS: Maternal sevoflurane exposure during neurogenic period temporarily induced abnormal INM of RGPs by targeting the Notch signalling pathway without inducing long-term effects on RGP progeny cell fate or offspring cognitive behaviours. More importantly, the defects of INM in hESC-derived cerebral organoids provide a novel insight into the effects of general anaesthesia on human brain development.


Assuntos
Anestésicos Inalatórios/efeitos adversos , Córtex Cerebral/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Receptores Notch/metabolismo , Sevoflurano/efeitos adversos , Animais , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Córtex Cerebral/patologia , Feminino , Feto/efeitos dos fármacos , Feto/metabolismo , Feto/patologia , Humanos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/citologia , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/patologia , Neurogênese/efeitos dos fármacos , Neuroglia/citologia , Neuroglia/efeitos dos fármacos , Neuroglia/patologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/patologia , Transdução de Sinais/efeitos dos fármacos
3.
Ann Transl Med ; 9(8): 708, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33987406

RESUMO

Background: Surgery is a highly technical procedure relying on high mental acuity and manual dexterity. The possibility that surgical outcomes and post-operative complications could be subject to influence by fatigue and/or circadian rhythms in surgeons has been investigated with inconsistent results. Methods: We conducted a retrospective study to assess the significance of operative timing on classifying surgical complications using an interpretable machine learning approach. We trained various linear, generative as well as tree models on the surgical record data collected from a university-affiliated, tertiary teaching hospital in China by performing parameter tuning using grid search cross-validation for optimizing the F1 score. Results: The results indicated that XGBoost was the best-performing model overall and its feature importance was shown to provide insight into possible timing-related associations with postoperative complications. We observed that the duration of surgery acted as the strongest indicator, and while surgery initiated at night (between 9 pm and 7 am) also ranked higher on the feature importance scale, it bore less significance than other factors such as the patient's age, gender, and type of surgery performed. Conclusions: We showed that surgical records could be used to demonstrate that operative timing might affect the occurrence of postoperative complications, but only in a relatively mild way while potentially entangling with multiple factors.

4.
Crit Rev Biochem Mol Biol ; 56(3): 236-254, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33761828

RESUMO

It is almost five decades since the discovery of the hypothalamic-pituitary-testicular axis. This refers to the hormonal axis that connects the hypothalamus, pituitary gland and testes, which in turn, regulates the production of spermatozoa through spermatogenesis in the seminiferous tubules, and testosterone through steroidogenesis by Leydig cells in the interstitium, of the testes. Emerging evidence has demonstrated the presence of a regulatory network across the seminiferous epithelium utilizing bioactive molecules produced locally at specific domains of the epithelium. Studies have shown that biologically active fragments are produced from structural laminin and collagen chains in the basement membrane. Additionally, bioactive peptides are also produced locally in non-basement membrane laminin chains at the Sertoli-spermatid interface known as apical ectoplasmic specialization (apical ES, a testis-specific actin-based anchoring junction type). These bioactive peptides are derived from structural laminins and/or collagens at the corresponding sites through proteolytic cleavage by matrix metalloproteinases (MMPs). They in turn serve as autocrine and/or paracrine factors to modulate and coordinate cellular events across the epithelium by linking the apical and basal compartments, the apical and basal ES, the blood-testis barrier (BTB), and the basement membrane of the tunica propria. The cellular events supported by these bioactive peptides/fragments include the release of spermatozoa at spermiation, remodeling of the immunological barrier to facilitate the transport of preleptotene spermatocytes across the BTB, and the transport of haploid spermatids across the epithelium to support spermiogenesis. In this review, we critically evaluate these findings. Our goal is to identify research areas that deserve attentions in future years. The proposed research also provides the much needed understanding on the biology of spermatogenesis supported by a local network of regulatory biomolecules.


Assuntos
Barreira Hematotesticular/metabolismo , Colágeno/metabolismo , Epitélio Seminífero/metabolismo , Espermatogênese , Espermatozoides/metabolismo , Animais , Humanos , Células Intersticiais do Testículo/metabolismo , Masculino , Células de Sertoli/metabolismo , Transdução de Sinais
5.
Asian J Androl ; 23(2): 123-128, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32896837

RESUMO

Collagen α3 (IV) chains are one of the major constituent components of the basement membrane in the mammalian testis. Studies have shown that biologically active fragments, such as noncollagenase domain (NC1)-peptide, can be released from the C-terminal region of collagen α3 (IV) chains, possibly through the proteolytic action of metalloproteinase 9 (MMP9). NC1-peptide was shown to promote blood-testis barrier (BTB) remodeling and fully developed spermatid (e.g., sperm) release from the seminiferous epithelium because this bioactive peptide was capable of perturbing the organization of both actin- and microtubule (MT)-based cytoskeletons at the Sertoli cell-cell and also Sertoli-spermatid interface, the ultrastructure known as the basal ectoplasmic specialization (ES) and apical ES, respectively. More importantly, recent studies have shown that this NC1-peptide-induced effects on cytoskeletal organization in the testis are mediated through an activation of mammalian target of rapamycin complex 1/ribosomal protein S6/transforming retrovirus Akt1/2 protein (mTORC1/rpS6/Akt1/2) signaling cascade, involving an activation of cell division control protein 42 homolog (Cdc42) GTPase, but not Ras homolog family member A GTPase (RhoA), and the participation of end-binding protein 1 (EB1), a microtubule plus (+) end tracking protein (+TIP), downstream. Herein, we critically evaluate these findings, providing a critical discussion by which the basement membrane modulates spermatogenesis through one of its locally generated regulatory peptides in the testis.

6.
Endocrinology ; 161(10)2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32761085

RESUMO

The blood-testis barrier (BTB) in the testis is an important ultrastructure to support spermatogenesis. This blood-tissue barrier undergoes remodeling at late stage VII to early stage IX of the epithelial cycle to support the transport of preleptotene spermatocytes across the BTB to prepare for meiosis I/II at the apical compartment through a mechanism that remains to be delineated. Studies have shown that NC1-peptide-derived collagen α3 (IV) chain in the basement membrane is a bioactive peptide that induces BTB remodeling. It also promotes the release of fully developed spermatids into the tubule lumen. Thus, this endogenously produced peptide coordinates these 2 cellular events across the seminiferous epithelium. Using an NC1-peptide complementary deoxyribonucleic acid (cDNA) construct to transfect adult rat testes for overexpression, NC1-peptide was found to effectively induce germ cell exfoliation and BTB remodeling, which was associated with a surge and activation of p-rpS6, the downstream signaling protein of mTORC1 and the concomitant downregulation of p-FAK-Y407 in the testis. In order to define the functional relationship between p-rpS6 and p-FAK-Y407 signaling to confer the ability of NC1-peptide to regulate testis function, a phosphomimetic (and thus constitutively active) mutant of p-FAK-Y407 (p-FAK-Y407E-MT) was used for its co-transfection, utilizing Sertoli cells cultured in vitro with a functional tight junction (TJ) barrier that mimicked the BTB in vivo. Overexpression of p-FAK-Y407E-MT blocked the effects of NC1-peptide to perturb Sertoli cell BTB function by promoting F-actin and microtubule cytoskeleton function, and downregulated the NC1-peptide-mediated induction of p-rpS6 activation. In brief, NC1-peptide is an important endogenously produced biomolecule that regulates BTB dynamics.


Assuntos
Membrana Basal/metabolismo , Colágeno Tipo IV/fisiologia , Quinase 1 de Adesão Focal/fisiologia , Fragmentos de Peptídeos/fisiologia , Espermatogênese/fisiologia , Testículo/metabolismo , Animais , Membrana Basal/química , Barreira Hematotesticular/metabolismo , Colágeno Tipo IV/química , Colágeno Tipo IV/genética , Quinase 1 de Adesão Focal/genética , Quinase 1 de Adesão Focal/metabolismo , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Mutação , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Fosforilação , Proteínas Tirosina Quinases/metabolismo , Ratos , Ratos Sprague-Dawley , Proteína S6 Ribossômica/metabolismo , Transdução de Sinais/fisiologia
7.
Chem ; 6(4): 1018-1031, 2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32685767

RESUMO

We describe a catalyst-free 1,2-trans-dihalogenation of alkynes with an unprecedented substrate scope and exclusive regio- and stereoselectivity. This versatile dihalogenation system-a combination of NX1S electrophile and alkali metal halide (MX2) in acetic acid-is applicable for diverse categories of alkynes (electron-rich or poor alkynes, internal and terminal alkynes, or heteroatoms such as O-, N-, S-substituted alkynes). The hydrogen bonding donor solvent acetic acid is essential for the in-situ generation of X1X2 electrophile, including ICl, IBr, BrCl, I2, and Br2.

8.
J Stroke Cerebrovasc Dis ; 29(8): 104850, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32689640

RESUMO

BACKGROUND: Following the recent discovery that microRNA-134-5p (miR-134-5p) is elevated in the early stages of acute myocardial infarction (AMI), we examined the specific role of miR-134-5p in cardiomyocytes during AMI. METHODS: To study miR-134-5p's role in the context of AMI, we used a combination of in vitro experiments in H2O2-treated or hypoxic cardiomyocyte cell cultures as well as in vivo experiments in a murine model of AMI. RESULTS: H2O2- and hypoxia-induced cardiomyocyte injury upregulated miR-134-5p expression. miR-134-5p overexpression increased cardiomyocyte apoptosis, whereas miR-134-5p inhibition reduced cardiomyocyte apoptosis. We discovered that the transcription factor cAMP-responsive element binding protein 1 (Creb1) is a functional target of miR-134-5p responsible for regulating cardiomyocyte apoptosis. In vivo AMI resulted in the upregulation and downregulation of miR-134-5p and Creb1 in the infarct area, respectively. Circulating miR-134-5p levels were also increased at days 1 and 2 post-AMI. Modulation of myocardial miR-124-5p expression by intramyocardial injection of antagomiR-134-5p or agomiR-134-5p significantly affected cardiomyocyte apoptosis, infarct size, and cardiac function in vivo. CONCLUSIONS: miR-134-5p/Creb1 axis dysregulation plays a role in hypoxia- or oxidative stress-induced cardiomyocyte apoptosis as well as AMI. Circulating miR-134-5p may show promise as a biomarker for AMI or post-AMI cardiac dysfunction. Manipulating the miR-134-5p/Creb1 axis through either inhibition of miR-134-5p or overexpression of Creb1 may show promise as a novel therapeutic strategy to attenuate cardiac dysfunction following AMI.


Assuntos
Antagomirs/administração & dosagem , Apoptose , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , MicroRNAs/antagonistas & inibidores , Infarto do Miocárdio/prevenção & controle , Miócitos Cardíacos/metabolismo , Regiões 3' não Traduzidas , Animais , Sítios de Ligação , Hipóxia Celular , Células Cultivadas , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Peróxido de Hidrogênio/toxicidade , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Miócitos Cardíacos/patologia , Estresse Oxidativo , Transdução de Sinais , Regulação para Cima
9.
Food Chem ; 319: 126546, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32179370

RESUMO

A rapid and sensitive immunochromatographic strip (ICS) based on a single-chain variable fragment (scFv) was developed for detecting fumonisin B1 (FB1). The ICS was based on a competitive reaction for colloidal gold-labeled scFv between FB1 and FB1-BSA, which was used along with sheep anti-mouse IgG as capture reagents immobilized at test and control lines, respectively, on a nitrocellulose membrane of the strip. The limit of detection of the ICS was 2.5 ng/mL (25 µg/kg) FB1 in buffer, and the sensitivity was eight times higher than that of monoclonal antibodies for the preparation of the scFv. The cross-reactivity of the scFv with common mycotoxins was determined by ICS, the results showed that the scFv were not against other mycotoxins. Eight naturally contaminated maize samples were analyzed with the scFv-based ICS and by LC-MS/MS. The results of analysis obtained with the strip assay showed good agreement with those obtained by LC-MS/MS.


Assuntos
Fumonisinas/análise , Anticorpos de Cadeia Única/imunologia , Zea mays/química , Animais , Anticorpos Monoclonais/imunologia , Cromatografia de Afinidade , Cromatografia Líquida , Reações Cruzadas , Fumonisinas/imunologia , Coloide de Ouro/química , Ovinos , Espectrometria de Massas em Tandem
10.
FASEB J ; 34(2): 3105-3128, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31909540

RESUMO

During the epithelial cycle of spermatogenesis, different sets of cellular events take place across the seminiferous epithelium in the testis. For instance, remodeling of the blood-testis barrier (BTB) that facilitates the transport of preleptotene spermatocytes across the immunological barrier and the release of sperms at spermiation take place at the opposite ends of the epithelium simultaneously at stage VIII of the epithelial cycle. These cellular events are tightly coordinated via locally produced regulatory biomolecules. Studies have shown that collagen α3 (IV) chains, a major constituent component of the basement membrane, release the non-collagenous (NC) 1 domain, a 28-kDa peptide, designated NC1-peptide, from the C-terminal region, via the action of MMP-9 (matrix metalloproteinase 9). NC1-peptide was found to be capable of inducing BTB remodeling and spermatid release across the epithelium. As such, the NC1-peptide is an endogenously produced biologically active peptide which coordinates these cellular events across the epithelium in stage VIII tubules. Herein, we used an animal model, wherein NC1-peptide cloned into the pCI-neo mammalian expression vector was overexpressed in the testis, to better understanding the molecular mechanism by which NC1-peptide regulated spermatogenic function. It was shown that NC1-peptide induced considerable downregulation on a number of cell polarity and planar cell polarity (PCP) proteins, and studies have shown these polarity and PCP proteins modulate spermatid polarity and adhesion via their effects on microtubule (MT) and F-actin cytoskeletal organization across the epithelium. More important, NC1-peptide exerted its effects by downregulating the expression of microtubule (MT) plus-end tracking protein (+TIP) called EB1 (end-binding protein 1). We cloned the full-length EB1 cDNA for its overexpression in the testis, which was found to block the NC1-peptide-mediated disruptive effects on cytoskeletal organization in Sertoli cell epithelium and pertinent Sertoli cell functions. These findings thus illustrate that NC1-peptide is working in concert with EB1 to support spermatogenesis.


Assuntos
Citoesqueleto de Actina/metabolismo , Barreira Hematotesticular/metabolismo , Colágeno/farmacologia , Proteínas Associadas aos Microtúbulos/metabolismo , Peptídeos/farmacologia , Espermátides/metabolismo , Espermatogênese/efeitos dos fármacos , Animais , Barreira Hematotesticular/citologia , Colágeno/química , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Peptídeos/química , Ratos , Ratos Sprague-Dawley , Epitélio Seminífero/citologia , Epitélio Seminífero/metabolismo , Espermátides/citologia , Junções Íntimas/metabolismo
11.
Reproduction ; 159(3): R111-R123, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31581125

RESUMO

Recent studies have shown that the testis is producing several biologically active peptides, namely the F5- and the NC1-peptides from laminin-γ3 and collagen α3 (IV) chain, respectively, that promotes blood-testis barrier (BTB) remodeling and also elongated spermatid release at spermiation. Also the LG3/4/5 peptide from laminin-α2 chain promotes BTB integrity which is likely being used for the assembly of a 'new' BTB behind preleptotene spermatocytes under transport at the immunological barrier. These findings thus provide a new opportunity for investigators to better understand the biology of spermatogenesis. Herein, we briefly summarize the recent findings and provide a critical update. We also present a hypothetical model which could serve as the framework for studies in the years to come.


Assuntos
Junções Aderentes/metabolismo , Barreira Hematotesticular/metabolismo , Colágeno Tipo IV/metabolismo , Laminina/metabolismo , Testículo/metabolismo , Animais , Humanos , Masculino , Espermatogênese
12.
Chemosphere ; 245: 125597, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31864041

RESUMO

Acephate is an organophosphate pesticide. It is widely used. However, whether it inhibits androgen synthesis and metabolism remains unclear. In the current study, we investigated the effect of acephate on the inhibition of androgen synthetic and metabolic pathways in rat immature Leydig cells after 3-h culture. Acephate inhibited basal androgen output in a dose-dependent manner with the inhibition starting at 0.5 µM. It significantly inhibited luteinizing hormone and 8-Br-cAMP stimulated androgen output at 50 µM. It significantly inhibited progesterone-mediated androgen output at 50 µM. Further study demonstrated that acephate down-regulated the expression of Hsd3b1 and its protein at ≥ 0.5 µM, Lhcgr at 5 µM and Star at 50 µM. Acephate directly blocked rat testicular HSD3B1 activity at 50 µM. Acephate did not affect other androgen synthetic and metabolic enzyme activities as well as ROS production, proliferation, and apoptosis of immature Leydig cells. In conclusion, acephate targets LHCGR, STAR, and HSD3B1, thus blocking androgen synthesis in rat immature Leydig cells and HSD3B1 is being the most sensitive target of acephate.


Assuntos
Androgênios/metabolismo , Células Intersticiais do Testículo/efeitos dos fármacos , Compostos Organotiofosforados/farmacologia , Fosforamidas/farmacologia , 8-Bromo Monofosfato de Adenosina Cíclica/análogos & derivados , 8-Bromo Monofosfato de Adenosina Cíclica/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Células Intersticiais do Testículo/metabolismo , Hormônio Luteinizante/antagonistas & inibidores , Hormônio Luteinizante/metabolismo , Masculino , Complexos Multienzimáticos/antagonistas & inibidores , Progesterona/farmacologia , Progesterona Redutase/antagonistas & inibidores , Ratos , Ratos Sprague-Dawley , Receptores do LH/antagonistas & inibidores , Esteroide Isomerases/antagonistas & inibidores , Testículo/efeitos dos fármacos , Testículo/metabolismo
13.
Exp Mol Pathol ; 113: 104357, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31837322

RESUMO

Acute lung injury (ALI) is a life-threatening syndrome characterized by excessive inflammation and apoptosis of alveolar epithelial cells. This study firstly investigated the role and mechanism of long non-coding RNA (lncRNA) growth arrest-specific 5 (GAS5) in regulating lipopolysaccharide (LPS)-induced inflammatory response and apoptosis of murine alveolar epithelial cell line MLE-12. The expression of GAS5, miR-429, and dual-specificity phosphatase 1 (DUSP1) were examined using quantitative Real-Time PCR (qRT-PCR) and western blot. The inflammatory responses were evaluated by detecting the levels of pro-inflammatory cytokines using ELISA. Cell apoptosis was assessed by TUNEL assay. The interactions among GAS5, miR-429, and DUSP1 were examined using luciferase reporter assay. The results showed that GAS5 and DUSP1 expression were decreased, whereas miR-429 was increased in lung tissues from LPS-induced ALI mice and LPS-treated MLE-12 cells. Furthermore, GAS5 overexpression decreased cell inflammatory responses and apoptosis in LPS-treated MLE-12 cells, which was reversed by miR-429 mimic and DUSP1 knockdown. Mechanistically, GAS5 acted as a competitive endogenous RNA by sponging miR-429 to facilitate DUSP1 expression. Our findings suggest that GAS5 suppresses inflammatory responses and apoptosis of alveolar epithelial cell MLE-12 by targeting miR-429/DUSP1 axis.


Assuntos
Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/patologia , Apoptose , Fosfatase 1 de Especificidade Dupla/metabolismo , Inflamação/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Lesão Pulmonar Aguda/genética , Animais , Apoptose/genética , Sequência de Bases , Linhagem Celular , Regulação da Expressão Gênica , Inflamação/patologia , Lipopolissacarídeos , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Modelos Biológicos , RNA Longo não Codificante/genética
14.
Green Chem ; 21(6): 1467-1471, 2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-31404296

RESUMO

The combination of two easily handled, highly acidic liquid HF complex reagents, DMPU-12HF and KHSO4-13HF, generated a highly acidic fluorination system that facilitated exclusive Markovnikov addition of HF to widely functionalized alkynes, including alkyne tethered drugs, or allenes to produce gem-difluorides with high atom economy, and with an easy workup.

15.
J Sci Food Agric ; 99(14): 6562-6571, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31321778

RESUMO

BACKGROUND: Excessive reactive oxygen species (ROS) may attack biological macromolecules and induce oxidative stress. The inhibition by ascorbic acid (AsA) on oxidative damage has been reported in fruits, while the barrier effect of ceramide has also been proven. However, there are few reports about the effects of ceramide-AsA interactions to enhance storability and boost antioxidant systems in fruits during storage. This study was conducted to study the synergistic effects of AsA in combination with ceramide on the quality of postharvest strawberry (Fragaria anannasa cv. Tianbao). RESULTS: Treatment with 100 mg L-1 AsA plus 1.2 mmol L-1 ceramide significantly delayed the rot of strawberries, reduced the water loss and the contents of ROS, malonaldehyde (MDA), and proline, however, increased the contents of total flavonoids, total phenols, and anthocyanins compared with other treatments. Also, treatment with 100 mg L-1 AsA plus 1.2 mmol L-1 ceramide significantly increased the activities of peroxidase (POD) and superoxide dismutase (SOD) but inhibited the activity of polyphenol oxidase (PPO). CONCLUSION: It is suggested that treatment with 100 mg L-1 AsA plus 1.2 mmol L-1 ceramide could significantly reduce the oxidative damage and maintain the storage quality of strawberries during storage by enhancing the antioxidant systems. © 2019 Society of Chemical Industry.


Assuntos
Antioxidantes/metabolismo , Ácido Ascórbico/farmacologia , Ceramidas/farmacologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Fragaria/efeitos dos fármacos , Catalase/metabolismo , Sinergismo Farmacológico , Armazenamento de Alimentos , Fragaria/química , Fragaria/metabolismo , Frutas/química , Frutas/efeitos dos fármacos , Frutas/metabolismo , Malondialdeído/metabolismo , Estresse Oxidativo , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
16.
Mar Drugs ; 17(6)2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31195737

RESUMO

Astaxanthin is an important antioxidant with many biological activities such as anti-tumor, anti-obesity, cardioprotective, and immuno-modulatory activities. Most of these biological activities are derived from (3S,3'S)-astaxanthin, while the activities of (3R,3'R)-astaxanthin are rarely reported. The purpose of this study was to investigate the effect of (3R,3'R)-astaxanthin on lipid metabolism and gut microbiota in mice fed with a high-fat diet. In this work, 40 male C57BL/6 mice were divided into 8 groups fed a high-fat diet supplemented or not with (3R,3'R)-astaxanthin or Xanthophyllomyces dendrorhous for 8 weeks. The weight gain, energy intake, fat index, plasma triacylglycerol and cholesterol, liver triacylglycerol and cholesterol, and gut microbiota were determined. The results showed that the addition of (3R,3'R)-astaxanthin/X. dendrorhous to the high-fat diet as a supplement prevented weight gain, reduced plasma and liver triacylglycerol, and decreased plasma and liver total cholesterol. The addition of (3R,3'R)-astaxanthin/X. dendrorhous also regulated the gut microbiota of the mice, which optimized the ratio of Bacteroides to Firmicutes and increased the content of Verrucomicrobia, especially Akkermansia. The changes in the gut microflora achieved a healthier structure, thus reducing the incidence of obesity. Thus (3R,3'R)-Astaxanthin has the function of regulating lipid metabolism and gut microbiota to prevent obesity caused by a high-fat diet. The production strain of (3R,3'R)-astaxanthin, X. dendrorhous, has the same function as astaxanthin in preventing obesity caused by a high-fat diet, which reflects its potential ability as a probiotic drug.


Assuntos
Basidiomycota/química , Dieta Hiperlipídica , Microbioma Gastrointestinal/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Animais , Basidiomycota/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Xantofilas/farmacologia
17.
Intervirology ; 62(1): 30-36, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31117098

RESUMO

BACKGROUND: Human adenoviruses (HAdV) are a common cause of viral conjunctivitis, making surveillance of them from sporadic cases of conjunctivitis important. METHODS: To acquire a better understanding of the epidemic genotypes of HAdV in outpatient children with adenoviral conjunctivitis in Jiangxi Province, China (2011-2012), 179 samples from cases with a high suspicion of HAdV were analyzed by PCR. Samples confirmed to be HAdV-positive by PCR were cultured in Hep-2 cells to isolate the viruses, which were then identified through hexon gene sequencing. RESULTS: The adenoviral conjunctivitis positivity rate was 74.86% (134/179), from which 71.64% (96/134) were infections in boys, and 92.54% (124/134) were infections in children under 5 years of age. Sixty-nine HAdV strains were isolated from the positive samples and 69 sequences were obtained. Phylogenetic analysis indicated that 33 strains (47.82%) clustered with HAdV-B7, 21 (30.43%) with HAdV-B3, 6 (8.70%) with HAdV-B55, 6 (8.70%) with HAdV-E4, 1 with HAdV-B21 (1.45%), 1 with HAdV-D37 (1.45%), and 1 with HAdV-D64 (1.45%). CONCLUSIONS: This is the first identification of HAdV-B55 relating to adenoviral conjunctivitis in China. These findings provide a firm basis for future surveillance of adenoviral conjunctivitis in China or other East Asian regions.


Assuntos
Infecções por Adenovirus Humanos/epidemiologia , Adenovírus Humanos/genética , Conjuntivite Viral/epidemiologia , Criança , Pré-Escolar , China/epidemiologia , Túnica Conjuntiva/virologia , DNA Viral/genética , Feminino , Genótipo , Humanos , Lactente , Masculino , Pacientes Ambulatoriais , Filogenia
18.
Life Sci ; 221: 143-151, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30763576

RESUMO

The neurotoxicity of anesthetics on developing brain has been a focused issue for years. However, controversy exists between human and animal studies and surgery may be a potential reason for this. The discovery of glymphatic system, a pathway eliminating soluble substance from central nervous system (CNS), together with recent evidence that surgery-induced Aß increase contributes to cognition dysfunction made us rethink about the influence of anesthetics on cognitive function. The function of glymphatic system was proved to be enhanced by sleep and sedation, so we assumed that under clinical situation Aß1-40 whose accumulation played important role in cognitive dysfunction was increased by surgery and eliminated from CNS by glymphatic system. The function of glymphatic system is facilitated by aquaporin-4 (AQP-4), a water channel expressed in highly polarized manor in astrocytic endfeet, whose transcription is regulated by nuclear factor of activated T cells 5 (NFAT5). Our results suggest that under brief operation and sevoflurane exposure, surgery may be the main cause of Aß increase and sevoflurane increase the elimination of Aß by up-regulating AQP-4 which is the key component in glymphatic system.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Aquaporina 4/metabolismo , Fragmentos de Peptídeos/metabolismo , Sevoflurano/metabolismo , Peptídeos beta-Amiloides/efeitos dos fármacos , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Encéfalo/metabolismo , Sistema Nervoso Central , Disfunção Cognitiva/metabolismo , Sistema Glinfático , Hipocampo/metabolismo , Masculino , Fatores de Transcrição NFATC/metabolismo , Fragmentos de Peptídeos/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Sevoflurano/farmacologia , Ativação Transcricional , Regulação para Cima
19.
ACS Catal ; 8(2): 904-909, 2018 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-30410816

RESUMO

We have developed an efficient synthesis of both (Z)- and (E)-chlorohaloalkenes via hydrochlorination of haloalkynes, based on two distinct hydrogen-bond-network-assisted catalytic systems: Brønsted acid catalysis and gold catalysis. Both systems offer high stereoselectivity, good chemical yields, and diverse functional group tolerance.

20.
Life Sci ; 209: 34-42, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-30071197

RESUMO

AIMS: The development of central nervous system requires proliferation of neural stem cells followed by differentiation. Cell cycle parameters are closely related with cell fate specification and differentiation. Recent researches indicated that wnt/ß-catenin signaling pathway might cause proliferation inhibition and differentiation abnormality through interfering NSCs cell cycle. Our previous research also showed that multiple sevoflurane exposure to neural stem cells inhibited proliferation via repressing transcription factor Pax6 and cyclin D1 through inhibiting wnt/ß-catenin pathway. All above encouraged us to figure out the effect of sevoflurane on cell cycle and neurogenesis. MAIN METHODS: Primary mouse cultured neural stem cells were used and exposed to 4.1% sevoflurane for 6 h in this study. The expression of ß-catenin, GSK-3ß, c-myc and cyclin D1 were determined by western blot and qRT-PCR. FACS was used to measure the cell cycle. The proliferation of NSCs was evaluated by EdU staining while the differentiation was evaluated by Tuj1 and GFAP staining on immunocytochemistry. KEY FINDINGS: We found that exposure to sevoflurane at a concentration of 4.1% for 6 h induced inhibition of wnt/ß-catenin pathway, cell cycle arrest at G0/G1 phase and an earlier switch from proliferation to differentiation. GSK-3ß specific inhibitor, CHIR99021, attenuated sevoflurane-induced cell cycle arrest and abnormality of neurogenesis in neural stem cells. SIGNIFICANCE: Our research suggested that sevoflurane arrested cell cycle at G0/G1 phase through inhibition of wnt/ß-catenin signaling pathway thus resulting in a premature differentiation in NSCs. This study presents a deeper understanding of the mechanism on cognitive impairment by sevoflurane exposure.


Assuntos
Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Éteres Metílicos/farmacologia , Células-Tronco Neurais/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Proteínas Wnt/antagonistas & inibidores , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/antagonistas & inibidores , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Sevoflurano , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
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