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1.
ACS Appl Mater Interfaces ; 15(33): 40133-40139, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37566758

RESUMO

Artificial water channels selectively transport water, excluding all ions. Unimolecular channels have been synthesized via complex synthetic steps. Ideally, simpler compounds requesting less synthetic steps should efficiently lead to selective channels by self-assembly. Herein, we report a self-assembled peptide-bound Ni2+ metallomacrocycle, 1, in which rim-peptide-bound units are connected to a central macrocycle obtained via condensation in the presence of Ni2+ ions. Compound 1 achieves a single-channel permeability up to 107-108 water/s/channel and insignificant ion transport, which is 1 order of magnitude lower than those for aquaporins. Molecular simulations probe that spongelike aggregates can form to generate transient cluster water pathways through the bilayer. Altogether, adaptive metallosupramolecular self-assembly is an efficient and simple way to construct selective channel superstructures.

2.
Front Vet Sci ; 9: 903615, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35711798

RESUMO

This study was conducted to evaluate the effects of organic trace elements (Cu, Fe, Zn, and Mn) on performance, egg quality, trace elements utilization, and intestinal function in late-phase laying hens. A total of 1,080 laying hens (Hy-line brown, 65 weeks old) were randomly assigned to four treatments with six replications of 45 layers each. The basal diet was prepared without adding exogenous trace elements. The control group was fed with a basal diet supplemented with 600 mg/kg of inorganic trace elements. The three treatment groups were fed basal diets supplemented with 300, 450, and 600 mg/kg organic trace elements (OTE300, 450, and 600), respectively. The results showed that there was no significant difference in growth performance among all treatments. However, OTE450 significantly improved the eggshell strength of laying hens (p < 0.05), but had no significant effects on haugh unit, egg yolk weight, eggshell weight, and eggshell thickness, compared with other groups. Moreover, compared with the control group, OTE450 significantly increased the contents of copper, iron, and zinc in serum (p < 0.05). Meanwhile, all of the trace elements had a lower deposition in the feces in organic trace elements groups (p < 0.05). Histological analysis showed that the addition of organic trace elements could significantly improve the villus height and villus concealment ratio (p < 0.05). In addition, the messenger RNA (mRNA) and protein expressions of divalent metal transporter 1 (DMT1), zinc transporter 1 (ZnT-1), and ferroportin 1 (FPN1) were the highest in the OTE450 group. In conclusion, OTE450 could improve egg quality, intestinal function, and trace element utilization efficiency. Thus, this study provides a theoretical basis for the application of low levels of organic trace elements in laying hens.

3.
J Am Chem Soc ; 143(38): 15653-15660, 2021 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-34520204

RESUMO

A hydrophobic light-driven rotary motor is functionalized with two 18-crown-6 macrocycles and incorporated into phospholipid bilayers. In the presence of this molecular construct, fluorescence assays and patch clamp experiments show the formation of selective alkali ion channels through the membrane. Further, they reveal a strongly accelerated ion transport mechanism under light irradiation. This increase of the fractional ion transport activity (up to 400%) is attributed to the out-of-equilibrium actuation dynamics of the light-driven rotary motors, which help to overcome the activation energy necessary to achieve translocation of alkali ions between macrocycles along the artificial channels.

4.
J Am Chem Soc ; 143(35): 14386-14393, 2021 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-34450001

RESUMO

Artificial water channels (AWCs) and their natural aquaporin counterparts selectively transport water. They represent a tremendous source of inspiration to devise biomimetic membranes for several applications, including desalination. They contain variable water-channel constructs with adaptative architectures and morphologies. Herein, we critically discuss the structural details that can impact the performances of biomimetic I quartets, obtained via adaptive self-assembly of alkylureido-ethylimidazoles HC4-HC18 in bilayer or polyamide (PA) membranes. We first explore the performances in bilayer membranes, identifying that hydrophobicity is an essential key parameter to increase water permeability. We compare various I quartets with different hydrophobic tails (from HC4 to HC18), and we reveal that a huge increase in single-channel water permeability, from 104 to 107 water molecules/s/channel, is obtained by increasing the size of the alkyl tail. Quantitative assessment of AWC-PA membranes shows that water permeability increases roughly from 2.09 to 3.85 L m-2 h-1 bar-1, for HC4 and HC6 reverse osmosis membranes, respectively, while maintaining excellent NaCl rejection (99.25-99.51%). Meanwhile, comparable HC8 loading induces a drop of performance reminiscent of a defective membrane formation. We show that the production of nanoscale sponge-like water channels can be obtained with insoluble, low soluble, and low dispersed AWCs, explaining the observed subpar performance. We conclude that optimal solubility enabling breakthrough performance must be considered to not only maximize the inclusion and the stability in the bilayer membranes but also achieve an effective homogeneous distribution of percolated particles that minimizes the defects in hybrid polyamide membranes.

5.
J Chem Phys ; 154(18): 184102, 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34241013

RESUMO

Understanding water transport mechanisms at the nanoscale level remains a challenge for theoretical chemical physics. Major advances in chemical synthesis have allowed us to discover new artificial water channels, rivaling with or even surpassing water conductance and selectivity of natural protein channels. In order to interpret experimental features and understand microscopic determinants for performance improvements, numerical approaches based on all-atom molecular dynamics simulations and enhanced sampling methods have been proposed. In this study, we quantify the influence of microscopic observables, such as channel radius and hydrogen bond connectivity, and of meso-scale features, such as the size of self-assembly blocks, on the permeation rate of a self-assembled nanocrystal-like artificial water channel. Although the absolute permeation rate extrapolated from these simulations is overestimated by one order of magnitude compared to the experimental measurement, the detailed analysis of several observed conductive patterns in large assemblies opens new pathways to scalable membranes with enhanced water conductance for the future design.

6.
J Am Chem Soc ; 143(11): 4224-4233, 2021 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-33635056

RESUMO

Artificial water channels (AWCs) are known to selectively transport water, with ion exclusion. Similarly to natural porins, AWCs encapsulate water wires or clusters, offering continuous and iterative H-bonding that plays a vital role in their stabilization. Herein, we report octyl-ureido-polyol AWCs capable of self-assembly into hydrophilic hydroxy channels. Variants of ethanol, propanediol, and trimethanol are used as head groups to modulate the water transport permeabilities, with rejection of ions. The hydroxy channels achieve a single-channel permeability of 2.33 × 108 water molecules per second, which is within the same order of magnitude as the transport rates for aquaporins. Depending on their concentration in the membrane, adaptive channels are observed in the membrane. Over increased concentrations, a significant shift occurs, initiating unexpected higher water permeation. Molecular simulations probe that spongelike or cylindrical aggregates can form to generate transient cluster water pathways through the bilayer. Altogether, the adaptive self-assembly is a key feature influencing channel efficiency. The adaptive channels described here may be considered an important milestone contributing to the systematic discovery of artificial water channels for water desalination.

7.
Anim Biosci ; 34(8): 1403-1414, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33152220

RESUMO

OBJECTIVE: This study explored the mechanism of the Kelch-like erythroid cell-derived protein with CNC homology-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway under conditions of zearalenone (ZEA)-induced oxidative stress in the duodenum of post-weaning gilts. METHODS: Forty post-weaning gilts were randomly allocated to four groups and fed diets supplemented with 0, 0.5, 1.0, or 1.5 mg/kg ZEA. RESULTS: The results showed significant reductions in the activity of the antioxidant enzymes total superoxide dismutase and glutathione peroxidase and increases the malondialdehyde content with increasing concentrations of dietary ZEA. Immunohistochemical analysis supported these findings by showing a significantly increased expression of Nrf2 and glutathione peroxidase 1 (GPX1) with increasing concentrations of ZEA. The relative mRNA and protein expression of Nrf2, GPX1 increased linearly (p<0.05) and quadratically (p<0.05), which was consistent with the immunohistochemical results. The relative mRNA expression of Keap1 decreased linearly (p<0.05) and quadratically (p<0.05) in the duodenum as the ZEA concentration increased in the diet. The relative mRNA expression of modifier subunit of glutamate-cysteine ligase (GCLM) increased quadratically (p<0.05) in all ZEA treatment groups and the relative mRNA expression of quinone oxidoreductase 1 (NQO1) catalytic subunit of glutamate-cysteine ligase decreased linearly (p<0.05) and quadratically (p<0.05) in the ZEA1.0 group and ZEA1.5 group. The relative protein expression of Keap1 and GCLM decreased quadratically (p<0.05) in the duodenum as the ZEA concentration increased in the diet, respectively. The relative protein expression of NQO1 increased linearly (p<0.05) and quadratically (p<0.05) in all ZEA treatment groups in the duodenum. CONCLUSION: These findings suggest that ZEA regulates the expression of key factors of the Keap1-Nrf2 signaling pathway in the duodenum, which enables resistance to ZEA-induced oxidative stress. Further studies are needed to examine the effects of ZEA induced oxidative stress on other tissues and organs in post-weaning gilts.

8.
Chemistry ; 27(7): 2224-2239, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32914905

RESUMO

Natural Aquaporin (AQP) channels are efficient water translocating proteins, rejecting ions. Inspired by this masterpiece of nature, Artificial Water Channels (AWCs) with controlled functional structures, can be potentially used to mimic the AQPs to a certain extent, offering flexible avenues toward biomimetic membranes for water purification. The objective of this paper is to trace the historical development and significant advancements of current reported AWCs. Meanwhile, we attempt to reveal important structural insights and supramolecular self-assembly principles governing the selective water transport mechanisms, toward innovative AWC-based biomimetic membranes for desalination.


Assuntos
Materiais Biomiméticos/metabolismo , Biomimética , Membranas Artificiais , Mimetismo Molecular , Salinidade , Cloreto de Sódio/isolamento & purificação , Água/química , Aquaporinas/metabolismo
9.
Angew Chem Int Ed Engl ; 60(2): 566-597, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-32212308

RESUMO

Owing to their significant physiological functions, especially as selective relays for translocation of physiological relevant species through cellular membranes, natural ion channels play important role in the living organisms. During the last decades, the field of self-assembled ion channels has been continuously developed. Convergent multidimensional self-assembly strategies have been used for the synthesis of unimolecular channels or non-covalent self-organized channels, designed to mimic natural ion channel proteins and for which a rich array of interconverting or adaptive channel conductance states can be observed. In this review, we give an overview on the development of various self-assembled artificial channels in a bottom-up approach, especially their design, self-assembly behaviour, transport activity in lipid bilayer membranes, mechanism of transport and comparison with natural ion channels. Finally, we discuss their applications, the potential challenges facing in this field as well as future development and perspectives.


Assuntos
Materiais Biomiméticos/química , Canais Iônicos/química , Materiais Biomiméticos/metabolismo , Calixarenos/química , Canais Iônicos/metabolismo , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Compostos Macrocíclicos/química , Estruturas Metalorgânicas/química
10.
Nat Nanotechnol ; 16(2): 190-196, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33169009

RESUMO

Inspired by biological proteins, artificial water channels (AWCs) can be used to overcome the performances of traditional desalination membranes. Their rational incorporation in composite polyamide provides an example of biomimetic membranes applied under representative reverse osmosis desalination conditions with an intrinsically high water-to-salt permeability ratio. The hybrid polyamide presents larger voids and seamlessly incorporates I-quartet AWCs for highly selective transport of water. These biomimetic membranes can be easily scaled for industrial standards (>m2), provide 99.5% rejection of NaCl or 91.4% rejection of boron, with a water flux of 75 l m-2 h-1 at 65 bar and 35,000 ppm NaCl feed solution, representative of seawater desalination. This flux is more than 75% higher than that observed with current state-of-the-art membranes with equivalent solute rejection, translating into an equivalent reduction of the membrane area for the same water output and a roughly 12% reduction of the required energy for desalination.

11.
Front Immunol ; 10: 1428, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31293587

RESUMO

POEMS syndrome is a rare paraneoplastic disorder characterized secondary to a rare plasma cell dyscrasia. Here, we aimed to analyze the clinical characteristics of large sample cases of POEMS in Chinese subjects through making a review of the Chinese literature. Four databases were electronically searched from inception until October 2016. Case reports and case series were identified. Six hundred studies with 1946 participants were identified. The first case was reported in 1986, and the number of reported cases peaked in 2009 and 2010. The top seven provinces on the number of reported cases were in the south-east area of China. The top three departments on the number of published papers and reported cases were ordinally department of Neurology, Hematology, and Endocrinology. The ratio of male to female was about 2.23. The range of age onset was from 10 to 81 years with the mean age of 46.39 (SD, 12.10 years). The initial symptoms of POEMS with peripheral neuropathy, edema and effusions, endocrinopathy, skin changes, and organomegaly accounted for 60.44, 15.72, 9.87, 8.05, and 2.13%, respectively, and subsequently acquired above symptoms as the prevalence was 99.49, 81.91, 75.56, 77.08, and 83.09%, respectively. The present study would help to understand the clinical presentations of POEMS syndrome in the Chinese population.


Assuntos
Síndrome POEMS/epidemiologia , Síndrome POEMS/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Criança , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
12.
J Agric Food Chem ; 66(30): 7899-7906, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29986586

RESUMO

Feedstuffs are severely contaminated by zearalenone (ZEA) worldwide. A specific dietary level of ZEA could cause malformations of the reproductive organs of sows, false estrus, decreased litter size, and abortion. However, the underlying mechanisms are still not clear. The objectives of the present study were to assess the effects of ZEA on morphology, distribution, and expression of estrogen receptors (ERα and ERß) in the ovaries of postweaning piglets. Furthermore, the relationship between ERs/glycogen synthase kinase (GSK)-3ß-dependent pathways mediated by ZEA and the Wnt-1/ß-catenin signaling pathway was examined. Forty healthy weaning piglets were allocated to the following four treatment groups: piglets fed with basal diet only (control), and ZEA0.5, ZEA1.0, and ZEA1.5, which were fed basal diets supplemented with ZEA at 0.5, 1.0, and 1.5 mg·kg-1, respectively. Then, the expression of GSK-3ß, ERα, ERß, and Wnt-1/ß-catenin were examined histomorphologically and immunohistochemically. Results showed that the proportion of primordial follicles (PrF's) decreased ( p < 0.001) but that of atretic primordial follicles (APFs) increased ( p < 0.001) with increasing dietary ZEA levels. More interestingly, the immunopositivity of ERß in the ovaries was stronger than that of ERα with the same treatment. The relative mRNA and protein expression levels of ERα, ERß, Wnt-1, ß-catenin, and GSK-3ß in the ovaries of postweaning gilts increased linearly ( p < 0.05) as dietary ZEA concentrations increased. Moreover, the accumulation of Wnt-1 and ß-catenin in the ovaries indicated that ZEA activated the Wnt-1/ß-catenin pathway, mediated by ERs/GSK-3ß. Our results strongly suggested that ovarian follicles in the ZEA (0.5-1.5 mg·kg-1)-treated groups were highly proliferative state, indicating that ZEA promoted ovarian development. The results also suggested that ZEA activates the ERs/GSK-3ß-dependent Wnt-1/ß-catenin signaling pathway, indicating its important role in accelerating development of the ovaries.


Assuntos
Micotoxinas/farmacologia , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/crescimento & desenvolvimento , Receptores de Estrogênio/metabolismo , Suínos/crescimento & desenvolvimento , Via de Sinalização Wnt/efeitos dos fármacos , Zearalenona/farmacologia , Ração Animal/efeitos adversos , Ração Animal/análise , Animais , Proliferação de Células/efeitos dos fármacos , Feminino , Contaminação de Alimentos/análise , Quinase 3 da Glicogênio Sintase/genética , Quinase 3 da Glicogênio Sintase/metabolismo , Folículo Ovariano/metabolismo , Receptores de Estrogênio/genética , Suínos/genética , Suínos/metabolismo , Desmame , Proteína Wnt1/metabolismo , beta Catenina/metabolismo
13.
Asian-Australas J Anim Sci ; 31(1): 32-39, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28920404

RESUMO

OBJECTIVE: In this study, we investigated the adverse effects of dietary zearalenone (ZEA) (0.5 to 1.5 mg/kg diet) on the localization and expression of the growth hormone receptor (GHR) in the uteri of post-weaning gilts and explored alternative mechanism of the reproductive toxicity of ZEA on piglets. METHODS: A total of forty healthy piglets (Duroc×Landrace×Large White) aged 28 d were selected for study. Piglets were transferred to single cages after 10 days' adaptation on an obstetric table. The animals were allocated to one of four treatments: a normal basal diet supplemented with 0 (Control), 0.5 (ZEA0.5), 1.0 (ZEA1.0), or 1.5 (ZEA1.5) mg/kg purified ZEA, and fed for 35 d after the 10-d adaptation. Analyzed ZEA concentrations in the diets were 0, 0.52±0.07, 1.04±0.03, and 1.51±0.13 mg/kg, respectively. At the end of the feeding trial, piglets were euthanized after being fasted for 12 h. Two samples of uterine tissue from each pig were rapidly collected, one of which was stored at -80°C for analysis of the relative mRNA and protein expression of GHR, and the second was promptly fixed in Bouin's solution for immunohistochemical analysis. RESULTS: The relative weight of the uteri and thickness of the myometrium and endometrium increased linearly (p<0.001) and quadratically (p<0.001) with an increasing level of ZEA. The results of immunohistochemical analysis indicated that GHR immunoreactive substance was mainly localizated in the cytoplasm of uterine smooth muscle, glandular epithelial, luminal epithelial, stromal, and vascular endothelial cells. In contrast, nuclear staining was rarely observed. The immunoreactive integrated optic density of GHR in the myometrium, luminal epithelium, glandular epithelium, and whole uteri of weaning gilts increased linearly (p<0.001) and quadratically (p<0.05) with an increasing level of ZEA. The mRNA and protein expression of GHR in the uteri of weaning gilts increased linearly (p<0.001) and quadratically (p<0.05) with an increasing level of ZEA. CONCLUSION: In conclusion, ZEA at a concentration of 0.5 mg/kg was sufficient to significantly thicken the myometrium and endometrium, and at a concentration of 1.0 mg/kg induced a high level of GHR expression to promote growth and development of the uteri. This revealed an alternative molecular mechanism whereby ZEA induces growth and development of the uteri and provides a theoretical basis for the revision of Chinese feed hygiene standards.

14.
Complement Ther Med ; 31: 71-81, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28434474

RESUMO

BACKGROUND: Many patients with multiple sclerosis (MS) resort to complementary and alternative medicine, which is used in 33%-80% of MS patients in the developed country. The purpose of this study is to assess the efficacy and safety of Chinese herbal medicine (CHM) as an adjunct therapy of patients with acute relapse of MS. METHODS: Six databases were searched for randomized-controlled trial of CHM for acute relapse of MS. The risk of bias was assessed by using the twelve criteria recommended by the Cochrane Back Review Group. The primary outcome measures of interest are the Expanded Disability Status Score, annual relapse frequency, annual relapse rate, and annual relapse interval. The secondary outcome measures are the clinical efficacy rate and adverse events. The selection criteria of high-frequency herbs for MS are those with cumulative frequency over 50%. We analyzed the data using Review Manager (version 5.3). RESULTS: A total of 1100 participants were included in the 20 studies from 2004 to 2015. The number of risk of bias which met the criteria varied from 5/12 to 7/12. The top 5 most frequently used herbs are ordinally Radix Angelicae Sinensis, Radix Glycyrrhizae, Radix Paeoniae Rubra, Radix Rehmanniae Preparata, and Bombyx Batryticatus. The meta-analysis showed a significant effect of CHM for improving Expanded Disability Status Score (P<0.01), annual relapse frequency (P<0.01) and the total clinical efficacy rate (P<0.01) compared with western conventional treatment. In analysis of annual relapse rate and annual relapse interval, there was a significant difference between CHMs and western conventional treatment (P<0.01). Adverse effects were monitored in 6 studies, and were well tolerated in all MS patients. CONCLUSIONS: The available evidence from present study supported but limited to recommend the routine use of CHM adjuvant therapy for MS because of the poor methodological quality and clinical heterogeneity. However, we identified an area that is worthy of further study. Furthermore, we selected high frequent use of CHMs as a promising candidate for further clinical application and MS trials. Further rigorous randomized-controlled trials are needed.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Esclerose Múltipla/tratamento farmacológico , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Recidiva , Adulto Jovem
15.
BMJ Open ; 7(4): e014280, 2017 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-28377394

RESUMO

BACKGROUND: Insomnia disorder is defined as a combination of dissatisfaction with sleep quantity or quality and a significant negative impact on daytime functioning. Chronic insomnia disorder refers to clinical symptoms of persistent insomnia at least three nights a week for at least 3 months. Prevalence estimates of insomnia disorder range from 12% to 20% in the adult population, with approximately 50% having a chronic course. The potential side effects of hypnotic medications hinder their clinical application. Thus, traditional Chinese medicine is considered as an alternative option for treating insomnia. OBJECTIVE: To evaluate the efficacy and safety of suanzaoren decoction (SZRD), a classic Chinese herbal prescription, for adult chronic insomnia disorder. METHODS/ANALYSIS: This is a randomised, double-blind, double-dummy, placebo-controlled clinical trial. A total of 150 patients with chronic insomnia disorder are randomised, allocated in a ratio of 1:1:1 to three groups: intervention group, control group and placebo group. The intervention group receives SZRD granule plus zolpidem tartrate (ZT) placebo; the control group receives ZT tablet plus SZRD granule placebo; and the placebo group receives ZT placebo and SZRD granule placebo. The patients receive medicine or placebo for 5 weeks and are followed up at 20 weeks. The primary outcome measures are polysomnography and Pittsburgh Sleep Quality Index. Secondary outcome measures are the Insomnia Severity Index, sleep diary and safety assessment. Outcomes will be assessed at baseline and after treatment. TRIAL REGISTRATION NUMBER: ChiCTR-IOR-16009198. pre-results.


Assuntos
Medicamentos de Ervas Chinesas/administração & dosagem , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Sono/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Polissonografia , Sono/efeitos dos fármacos , Distúrbios do Início e da Manutenção do Sono/diagnóstico , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
16.
Front Aging Neurosci ; 8: 276, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27999539

RESUMO

Ginkgo biloba extracts (GBEs) have been recommended to improve cognitive function and to prevent cognitive decline, but earlier evidence was inconclusive. Here, we evaluated all systematic reviews of GBEs for prevention of cognitive decline, and intervention of mild cognitive impairment (MCI) and dementia. Six databases from their inception to September 2015 were searched. Ten systematic reviews were identified, including reviews about Alzheimer's disease (n = 3), about vascular dementia (n = 1), about both Alzheimer's disease and vascular dementia (n = 2), about Alzheimer's disease, vascular dementia and mixed dementia (n = 3), and a review about MCI (n = 1). Based on the overview quality assessment questionnaire, eight studies were scored with at least 5 points, while the other two scored 4 points and 3 points, respectively. Medication with GBEs showed improvement in cognition, neuropsychiatric symptoms, and daily activities, and the effect was dose-dependent. Efficacy was convincingly demonstrated only when high daily dose (240 mg) was applied. Compared with placebo, overall adverse events and serious adverse events were at the same level as placebo, with less adverse events in favor of GBE in the subgroup of Alzheimer's disease patients, and fewer incidences in vertigo, tinnitus, angina pectoris, and headache. In conclusion, there is clear evidence to support the efficacy of GBEs for MCI and dementia, whereas the question on efficacy to prevent cognitive decline is still open. In addition, GBEs seem to be generally safe.

17.
Artigo em Inglês | MEDLINE | ID: mdl-26495006

RESUMO

Rhubarb root and rhizome (RRR) has been clinically used for stroke at least 2000 years and is still used in modern times in both China and elsewhere worldwide. The objective of present study was to evaluate the efficacy of active compounds of RRR (ACRRR) for experimental ischemic stroke. Studies of ACRRR in animal models of ischemic stroke were identified from 5 databases until April 2014. Study quality for each included article was evaluated according to the CAMARADES 10-item checklist. Outcome measures were neurological deficit score and infarct size. All the data were analyzed using RevMan 5.1 software. As a result, 20 studies were identified describing procedures involving 577 animals. The quality score of studies ranges from 2 to 6, and the median was 3.4. Six studies showed significant effects of ACRRR for improving infarct size compared with model group (P < 0.01). Six studies indicated significant effects of ACRRR for improving the neurological deficit scores according to Zea longa criterion or eight-point criterion (P < 0.01). In conclusion, these findings demonstrated a possible efficacy of ACRRR that have potential neuroprotective effect for experimental ischemic stroke. However, these apparently positive findings should be interpreted with caution because of the methodological flaws.

18.
Comput Biol Chem ; 51: 42-50, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24929544

RESUMO

To clarify the molecular evolution and characteristic of beta estrogen receptor (ERß) gene in Jining Gray goat in China, the entire ERß gene from Jining Gray goat ovary was amplified, identified and sequenced, and the gene sequences were compared with those of other animals. Functional structural domains and variations in DNA binding domains (DBD) and ligand binding domains (LBD) between Jining Gray goat and Boer goat were analyzed. The results indicate that the ERß gene in Jining Gray goat includes a 1584bp sequence with a complete open-reading-frame (ORF), encoding a 527 amino acid (aa) receptor protein. Compared to other species, the nucleotide homology is 73.9-98.9% and the amino acid homology is 79.5-98.5%. The main antigenic structural domains lie from the 97th aa to the 286th aa and from the 403rd aa to the 527th aa. The hydrophilicity and the surface probability of the structural domains are distributed throughout a range of amino acids. There are two different amino acids in the DBD and three different amino acids in the LBD between Jining Gray and Boer goats, resulting in dramatically different spatial structures for ERß protein. These differences may explain the different biological activities of ERß between the two goat species. This study firstly acquired the whole ERß gene sequence of Jining Gray goat with a complete open reading frame, and analyzed its gene evolutionary relationship and predicted its mainly functional structural domains, which may very help for further understanding the genome evolution and gene diversity of goat ERß.


Assuntos
Receptor beta de Estrogênio/química , Cabras/genética , Fases de Leitura Aberta , Ovário/química , Motivos de Aminoácidos , Animais , China , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Evolução Molecular , Feminino , Expressão Gênica , Cabras/classificação , Modelos Moleculares , Dados de Sequência Molecular , Ovário/metabolismo , Filogenia , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
19.
Anim Reprod Sci ; 127(3-4): 164-8, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21880440

RESUMO

To explore the expression of androgen receptor (AR) and estrogen receptor alpha (ERα) in the developing pituitary of male lamb, we detected AR and ERα expression in the anterior pituitary of lambs aged 2-7 months old by immunohistochemistry. The results showed that both AR immunoreactivity (AR-ir) and ERα immunoreactivity (ERα-ir) were localized in the nuclei of anterior pituitary cell. The percentage of the anterior pituitary cells expressing ERα fluctuated from 8.79±0.02% to 11.80±0.04% during the examined stages, but fell significantly to the lowest level at 6 months. While the proportion of AR-ir showed significant changes, it was in 11.52±1.26% at 2 months, it firstly increased to 19.86±1.03% at 3 months, and then significantly decreased to 8.18±1.17% at 6 months (P<0.05). The expression of both AR-ir and ERα-ir were the lowest level at 6 months old. By staining for PCNA, we observed that the changes in expression of AR and ERα at different lamb ages did not result from cell proliferation of anterior pituitary cells. These results indicate that both AR and ERα are important in regulation of secretary function of anterior pituitary in sheep lamb, although the related mechanism needs to be elucidated further.


Assuntos
Receptor alfa de Estrogênio/metabolismo , Hipófise/crescimento & desenvolvimento , Hipófise/metabolismo , Receptores Androgênicos/metabolismo , Ovinos/crescimento & desenvolvimento , Fatores Etários , Animais , Núcleo Celular/metabolismo , Proliferação de Células , Regulação da Expressão Gênica no Desenvolvimento , Imuno-Histoquímica , Masculino , Hipófise/citologia , Fatores Sexuais , Ovinos/metabolismo
20.
Prostaglandins Other Lipid Mediat ; 90(3-4): 94-7, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19765668

RESUMO

To explore the potential mechanism of how uterine innervations would affect the uterine mast cell (MC) population and functions during the periimplantation. We herein first examined the consequence of uterine neurectomy on embryo implantation events. We observed that amputation of autonomic nerves innervating the uterus led to on-time implantation failure in rats. Exploiting MC culture and ELISA approaches, we then further analyzed the effect of neurectomy on cellular histamine levels and its release from uterine MCs, to elucidate the relation of the autonomic nerves and local cellular immunity in the uterine during early pregnancy. We observed that disconnection of autonomic nerve innervation significantly increased the population of uterine MCs. Most interestingly, these increased number of uterine MCs in neuroectomized rats contained a much reduced cellular level of histamine. Our subsequent challenge experiments revealed that uterine MCs in nerve amputated rats exhibited enhanced histamine releasing rate in response to substance P and antiIgE, suggesting loss of nerve innervation in the uterus not only increases the population of uterine MCs, but also facilitates the release of histamine from MCs, thus subsequently interfere with the normal implantation process. Collectively, our findings provide a new line of evidence supporting the concept that immune-neuro-endocrine network plays important role during pregnancy establishment and maintenance.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Implantação do Embrião/fisiologia , Mastócitos/fisiologia , Útero/inervação , Animais , Sistema Nervoso Autônomo/imunologia , Implantação do Embrião/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Liberação de Histamina/fisiologia , Imunidade Celular/fisiologia , Masculino , Mastócitos/imunologia , Gravidez , Distribuição Aleatória , Ratos , Ratos Wistar , Útero/citologia , Útero/imunologia
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