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1.
Environ Toxicol ; 39(6): 3330-3340, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38440903

RESUMO

OBJECTIVE: Phthalates (PEs) could cause reproductive harm to males. A mixture of three widely used PEs (MPEs) was used to investigate the ameliorative effects of zinc (Zn) and vitamin E (VE) against male reproductive toxicity. METHODS: Fifty male SD rats were randomly divided into five groups (n = 10). Rats in MPEs group were orally treated with 160 mg/kg/d MPEs, while rats in MPEs combined Zn and/or VE groups were treated with 160 mg/kg/d MPEs plus 25 mg/kg/d Zn and/or 25 mg/kg/d VE. After intervention for 70 days, it's was measured of male reproductive organs' weight, histopathological observation of sperms and testes, serum hormones, PIWI proteins and steroidogenic proteins. RESULTS: Compared with control, anogenital distance, testes weight, epididymides weight, and sex hormones were significantly decreased, while the sperm malformation rate was markedly increased in MPEs group (p < .05); the testicular tissues were injured in MPEs group with disordered and decreased spermatids, and arrested spermatogenesis. PIWIL1, PIWIL2, StAR, CYP11A1 and CYP19A1 were down-regulated in MPEs group (p < .05). However, the alterations of these parameters were restored in MPEs combined Zn and/or VE groups (p < .05). CONCLUSION: Zn and/or VE improved steroid hormone metabolism, and inhibited MPEs' male reproductive toxicity.


Assuntos
Ácidos Ftálicos , Ratos Sprague-Dawley , Testículo , Vitamina E , Zinco , Animais , Masculino , Testículo/efeitos dos fármacos , Testículo/patologia , Vitamina E/farmacologia , Ácidos Ftálicos/toxicidade , Espermatozoides/efeitos dos fármacos , Ratos , Reprodução/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos
2.
Ecotoxicol Environ Saf ; 270: 115920, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38171105

RESUMO

Phthalates (PEs) are widely used plasticizers in polymer products, and humans are increasingly exposed to them. This study was designed to investigate the alleviative effect of phytochemicals quercetin (Que) against male reproductive toxicity caused by the mixture of three commonly used PEs (MPEs), and further to explore the underlying mechanism. Forty-eight male SD rats were randomly and evenly divided into control group, Que group, MPEs group and MPEs+Que group (n = 12); The oral exposure doses of MPEs and Que were 450 mg/kg/d and 50 mg/kg/d, respectively. After 91 days of continuous intervention, compared with control group, the testes weight, epididymis weight, serum sex hormones, and anogenital distance were significantly decreased in MPEs group (P < 0.05); Testicular histopathological observation showed that all seminiferous tubules were atrophy, leydig cells were hyperplasia, spermatogenic cells growth were arrested in MPEs group. Ultrastructural observation of testicular germ cells showed that the edges of the nuclear membranes were indistinct, and the mitochondria were severely damaged with the cristae disrupted, decreased or even disappeared in MPEs group. Immunohistochemistry and Western blot analysis showed that testicular CYP11A1, CYP17A1 and 17ß-HSD were up-regulated, while StAR, PIWIL1 and PIWIL2 were down-regulated in MPEs group (P < 0.05); However, the alterations of these parameters were restored in MPEs+Que group. The results indicated MPEs disturbed steroid hormone metabolism, and caused male reproductive injuries; whereas, Que could inhibit MPEs' male reproductive toxicity, which might relate to the restored regulation of steroid hormone metabolism.


Assuntos
Ácidos Ftálicos , Quercetina , Testículo , Humanos , Ratos , Masculino , Animais , Quercetina/farmacologia , Ratos Sprague-Dawley , Hormônios Esteroides Gonadais/metabolismo , Esteroides/metabolismo , Testosterona , Proteínas Argonautas/metabolismo , Proteínas Argonautas/farmacologia
3.
Toxicol Appl Pharmacol ; 483: 116816, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38218207

RESUMO

Phthalates (PEs), such as di(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP) and butyl benzyl phthalate (BBP) could cause reproductive and developmental toxicities, while human beings are increasingly exposed to them at low-doses. Phytochemical quercetin (Que) is a flavonoid that has estrogenic effect, anti-inflammatory and anti-oxidant effects. This study was conducted to assess the alleviative effect of Que. on male reproductive toxicity induced by the mixture of three commonly used PEs (MPEs) at low-dose in rats, and explore the underlying mechanism. Male rats were treated with MPEs (16 mg/kg/day) and/or Que. (50 mg/kg/d) for 91 days. The results showed that MPEs exposure caused male reproductive injuries, such as decreased serum sex hormones levels, abnormal testicular pathological structure, increased abnormal sperm rate and changed expressions of PIWIL1 and PIWIL2. Furthermore, MPEs also changed the expression of steroidogenic proteins in steroid hormone metabolism, including StAR, CYP11A1, CYP17A1, 17ß-HSD, CYP19A1. However, the alterations of these parameters were reversed by Que. MPEs caused male reproductive injuries in rats; Que. inhibited MPEs' male reproductive toxicity, which might relate to the improvement of testosterone biosynthesis.


Assuntos
Dietilexilftalato , Ácidos Ftálicos , Humanos , Ratos , Masculino , Animais , Quercetina/farmacologia , Testosterona , Ratos Sprague-Dawley , Sêmen/metabolismo , Ácidos Ftálicos/toxicidade , Ácidos Ftálicos/metabolismo , Testículo , Dietilexilftalato/toxicidade , Proteínas Argonautas/metabolismo , Proteínas Argonautas/farmacologia
4.
Transl Cancer Res ; 11(8): 2887-2901, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36093517

RESUMO

Background: Cutaneous squamous cell carcinoma (cSCC), a kind of skin cancer with high rates of morbidity and mortality, occurs frequently in the clinic. Although early surgical treatment can achieve good results, there is no effective prevention and treatment for the recurrence and metastasis of cSCC. As a useful resource to protect humans from disease, traditional Chinese medicine (TCM) has been adopted by clinicians for thousands of years. Methods: In this study, we collected a Chinese medicine formula and then employed a data mining method to analyze drug combinations of Si-Jun-Zi (SJZ) decoction. Multiple databases were used in this study to predict various ingredients, compounds, and their targets in the decoction. The potential targets of cSCC were also obtained from the database in the same way. In addition, as bioinformatics analysis methods, Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were used in our research as supplementary means to network pharmacology. Finally, we used ultra-performance liquid chromatography (UPLC) fingerprinting to analyze the effective components of the TCM decoction. Results: We detected 559 active compounds from Ginseng, Largehead Atractylodes, India Bread, and Glycyrrhiza Inflata, and selected 136 molecules under specific conditions. The mechanisms of the TCM formula were illustrated by the network pharmacology, such as compounds-herb network, compounds-target network, disease-target network, and target-target interaction network, as well as characteristics of the TCM. Then, GO analysis and KEGG analysis were performed on the compounds in the network using multiple methods of data mining and bioinformatics, and 10 candidate targets were identified. In addition, the UPLC fingerprinting method was used to analyze the components of SJZ decoction. Conclusions: Network pharmacology was performed to investigate the characteristics and mechanism of SJZ decoction, and a bioinformatics method was used to analyze the relationship between the effective compounds of the SJZ TCM decoction and cSCC-related specific targets and pathways, to find a variety of candidate compounds with multi-target activity.

5.
Food Chem ; 390: 133151, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35567974

RESUMO

Galacto-oligosaccharides (GOS) are important prebiotic supplements for commercial nutraceutical food. The prebiotic efficacy of functional GOS is dependent on their chemical profile. Screening potential markers aids specifications and quality control of GOS materials. However, profiling analysis of GOS with a degree of polymerization (DP) ≥ 4 is still challenging. This study presents a porous graphitic carbon liquid chromatography-orbitrap tandem mass spectrometry-based method that characterized 58 linear and 10 branched GOS and detected 59 non-reducing GOS from DP2 to DP6. The results indicated that 15 major group components with DP2-DP5 accounted for more than 65% of total GOS content in GOS samples, while non-reducing GOS components accounted for only 2.8-7.6%. Substantial variations in components occurred in samples from different batches and sources. Structural and constitutive diversity were dominated by DP3-DP5. This method can help control the quality of GOS products and be used to investigate the structural and prebiotic-efficacy relationships.


Assuntos
Dissacarídeos , Grafite , Carbono , Cromatografia Líquida , Galactose/química , Oligossacarídeos/química , Porosidade , Prebióticos/análise , Espectrometria de Massas em Tandem/métodos
6.
J Chromatogr A ; 1670: 462948, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35339018

RESUMO

Metal wires have been widely used as substrates for solid-phase microextraction (SPME) fibers instead of commonly fragile silica fibers, but complicated coating modification of their surface is required. Herein, a series of brass wires were soaked in an acidic iron trichloride solution with ultrasonication, which etched the brass surface through a redox reaction. The surface wettability of the pristine brass wire was transformed from hydrophobic to hydrophilic owing to the formation of micro/nanoscale hierarchical structures. After modification with n-octadecanethiol (ODT) and 2-naphthalenethiol (NT), respectively, both wires exhibited superhydrophobicity. Characterization of the resulting wires was conducted using SEM and EDS, and the surface wettability was measured by a contact angle goniometer using identical brass meshes. To build an in-tube SPME-high-performance liquid chromatography (HPLC) online system, the extraction tube was connected with HPLC equipment by replacing the sample loop of a six-port valve. Four types of wires, including the pristine hydrophobic brass wire, the hydrophilic wire after chemical etching, and both superhydrophobic wires, were comparatively applied to the extraction of six estrogens. The optimized extraction conditions were a sample volume of 60 mL, an injection rate of 2 mL/min, and a desorption time of 2 min at a flow rate of 1 mL/min. The results showed that the highest estrogen extraction efficiency was obtained using the superhydrophobic wire modified by NT, with the enrichment factors in the range of 36-350. Furthermore, the superhydrophobic NT wire exhibited a higher extraction efficiency than the ODT wire with identical superhydrophobicity. This demonstrated that the higher extraction efficiency was mainly dependent on  π-π interactions between the sorbent containing naphthalene rings and the target compounds containing benzene rings, rather than surface wettability.


Assuntos
Cobre , Microextração em Fase Sólida , Cromatografia Líquida de Alta Pressão/métodos , Cobre/química , Estrogênios/análise , Microextração em Fase Sólida/métodos , Molhabilidade , Zinco
7.
Echocardiography ; 37(10): 1627-1633, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32969521

RESUMO

OBJECTIVE: This study sought to investigate the variation of right heart structure pre- and post-operation as risk factors for moderate to severe pulmonary regurgitation (PR) after repaired Tetralogy of Fallot and the best "cutoff" values for the transannular patch (TAP). METHODS: We collected surgical, echocardiographic, and computed tomographic data of Teralogy of Fallot (TOF) patients over two years and calculated z-score values based on the echocardiographic data. Based on the PR level after follow-up, the patients were divided into two groups, trivial to mild PR and moderate to severe PR. A multivariate logistic regression analysis was performed, and the receiver operating characteristic curve analysis was used to find the best "cutoff" value for risk factors. RESULTS: A total of 104 TOF patients were included in our cohort study. From the multivariate analysis, correction strategy (P = .002), difference in zRVOT (OR 1.974, 95% CI 1.354 to 2.878, P < .0001), and zPVA (OR 3.605, 95% CI 1.980 to 6.562, P < .0001) were the significant risk factors for moderate to severe PR. The "cutoff" value for the difference in zPVA that could predict moderate to severe PR in the TAP group was 3, and the optimal "cutoff" value for TAP was -1.4. CONCLUSIONS: The TAP is a risk factor for significant PR after surgery. We recommend the optimal "cutoff" value for TAP is -1.4 calculated using Shan-Shan Wang's data set. During the procedure, to limit the RVOT resection and restrict the enlargement of pulmonary annulus within a variation of z-score as 3 would reduce significant PR.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Insuficiência da Valva Pulmonar , Valva Pulmonar , Tetralogia de Fallot , Estudos de Coortes , Humanos , Valva Pulmonar/diagnóstico por imagem , Valva Pulmonar/cirurgia , Insuficiência da Valva Pulmonar/diagnóstico por imagem , Insuficiência da Valva Pulmonar/etiologia , Insuficiência da Valva Pulmonar/cirurgia , Estudos Retrospectivos , Tetralogia de Fallot/diagnóstico por imagem , Tetralogia de Fallot/cirurgia , Resultado do Tratamento
8.
Nanoscale ; 7(29): 12592-7, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26145435

RESUMO

In this study, we devised a two-V/III-ratio procedure to control the Au-assisted growth of defect-free InAs nanowires in molecular beam epitaxy. The demonstrated two V/III ratio procedure consists of a first high V/III ratio growth step to prepare the nanowire foundation on the substrate surface, followed by a low V/III ratio step to induce the nanowire growth. By manipulating the V/III ratios in different steps, we have achieved the controlled growth of pure defect-free zinc-blende structured InAs nanowires on the GaAs {1̄1̄1̄} substrates. This study provides an approach to control not only the crystal structure of semiconductor nanowires, but also their structural qualities.

9.
Nano Lett ; 15(2): 876-82, 2015 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-25580886

RESUMO

In this study, we demonstrate the epitaxial growth of ⟨001̅⟩ defect-free zinc-blende structured InAs nanowires on GaAs {111}B substrate using Au catalysts in molecular beam epitaxy. It has been found that the catalysts and their underlying ⟨001̅⟩ nanowires have the orientation relationship of {11̅03}C//{002̅}InAs and [3̅302]C//[11̅0]InAs due to their small in-plane lattice mismatches between their corresponding lattice spacings perpendicular to the {001̅} atomic planes of the nanowires, leading to the formation of the {001̅} catalyst/nanowire interfaces, and consequently the formation of ⟨001̅⟩ nanowires. This study provides a practical approach to manipulate the crystal structure and structural quality of III-V nanowires through carefully controlling the crystal phase of the catalysts.

10.
BMC Neurosci ; 14: 76, 2013 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-23902361

RESUMO

BACKGROUND: 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induces Parkinson's disease (PD)-like neurodegeneration of dopaminergic neurons in the substantia nigra pars compacta (SNpc) via its oxidized product, 1-methyl-4-phenylpyridinium (MPP+), which is transported by the dopamine (DA) transporter into DA nerve terminals. DA receptor subtype 3 (D3 receptor) participates in neurotransmitter transport, gene regulation in the DA system, physiological accommodation via G protein-coupled superfamily receptors and other physiological processes in the nervous system. This study investigated the possible correlation between D3 receptors and MPTP-induced neurotoxicity. A series of behavioral experiments and histological analyses were conducted in D3 receptor-deficient mice, using an MPTP-induced model of PD. RESULTS: After the fourth MPTP injection, wild-type animals that received 15 mg/kg per day displayed significant neurotoxin-related bradykinesia. D3 receptor-deficient mice displayed attenuated MPTP-induced locomotor activity changes. Consistent with the behavioral observations, further neurohistological assessment showed that MPTP-induced neuronal damage in the SNpc was reduced in D3 receptor-deficient mice. CONCLUSIONS: Our study indicates that the D3 receptor might be an essential molecule in MPTP-induced PD and provides a new molecular mechanism for MPTP neurotoxicity.


Assuntos
Intoxicação por MPTP/metabolismo , Intoxicação por MPTP/fisiopatologia , Receptores de Dopamina D3/fisiologia , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Análise de Variância , Animais , Modelos Animais de Doenças , Esquema de Medicação , Comportamento Exploratório/efeitos dos fármacos , Comportamento Exploratório/fisiologia , Intoxicação por MPTP/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Desempenho Psicomotor/efeitos dos fármacos , Receptores de Dopamina D3/deficiência , Fatores de Tempo , Tirosina 3-Mono-Oxigenase/metabolismo
11.
Invest Ophthalmol Vis Sci ; 53(9): 5334-43, 2012 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-22736612

RESUMO

PURPOSE: We investigated the potential of human parthenogenetic embryonic stem cells (hPESCs) to differentiate into RPE cells, and identified development-regulating microRNAs (miRNAs). METHODS: RPE cells were derived from hPESCs. The expression of markers and miRNA expression profiles during differentiation were studied by immunocytochemistry, real-time RT-PCR, and miRNA expression array at three time points. Human fetal RPE (hfRPE) cells also were analyzed. The target genes of candidate miRNAs then were validated. RESULTS: hPESC-derived RPE cells exhibited similar morphology and pigmentation to hfRPE cells. The expression of markers during differentiation indicated that the hPESC-derived RPE cells were immature. Most specific miRNAs had a role at some time point during the differentiation and maturation of RPE from hPESCs, except for two miRNAs (miR-204 and the miR-302 family). The miR-204 was upregulated and miR-302 was down-regulated throughout the process. Subsequently, pigmented clusters and RPE signature gene expression increased significantly in the miR-204 overexpression group and miR-302 inhibition group compared to the control groups. CTNNBIP1 and TGFBR2 were confirmed to be the target genes of miR-204 and miR-302, respectively. CONCLUSIONS: hPESCs can develop into RPE-like cells and, thus, can be additional promising sources of RPE cells in cell therapy. The miR-204, miR-302s, and their targets are involved in regulating directed differentiation during the full course, thereby contributing to the search for a new method of improving differentiation efficiency using miRNAs.


Assuntos
Diferenciação Celular/fisiologia , Células-Tronco Embrionárias/citologia , MicroRNAs/metabolismo , Epitélio Pigmentado da Retina/citologia , Proteínas Adaptadoras de Transdução de Sinal , Células Cultivadas , Regulação para Baixo/fisiologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , MicroRNAs/genética , Partenogênese , Proteínas Serina-Treonina Quinases/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Regulação para Cima/fisiologia
12.
ACS Nano ; 6(7): 6005-13, 2012 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-22724925

RESUMO

The doping-dependent photoconductive properties of individual GaAs nanowires have been studied by conductive atomic force microscopy. Linear responsivity against the bias voltage is observed for moderate n-doped GaAs wires with a Schottky contact under illumination, while that of the undoped ones exhibits a saturated response. The carrier lifetime of a single nanowire can be obtained by simulating the characteristic photoelectric behavior. Consistent with the photoluminescence results, the significant drop of minority hole lifetime, from several hundred to subpicoseconds induced by n-type doping, leads to the distinct photoconductive features. Moreover, by comparing with the photoelectric behavior of AlGaAs shelled nanowires, the equivalent recombination rate of carriers at the surface is assessed to be >1 × 10(12) s(-1) for 2 × 10(17)cm(-3) n-doped bare nanowires, nearly 30 times higher than that of the doping-related bulk effects. This work suggests that intentional doping in nanowires could change the charge status of the surface states and impose significant impact on the electrical and photoelectrical performances of semiconductor nanostructures.

13.
J Assist Reprod Genet ; 29(8): 735-44, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22661130

RESUMO

PURPOSE: Retinal pigment epithelium cells derived from human embryonic stem cells (ESCs) could be useful for restoring retinal function in age-related macular degeneration. However the use of non-human feeder cells to support the growth of ESCs for clinical applications raises the concern of possible contamination because of direct contact between animal and human cells. METHODS: In this study, we produced human ESCs using human fibroblast feeder layers isolated from foreskin and abdominal tissues. Using this system, human ESCs differentiated into retinal pigment epithelium cells in differentiation medium. RESULTS: Seven human ESC lines were established from 18 blastocysts. These human ESCs showed normal morphology, expressed all expected cell surface markers, had the ability to form embryoid bodies upon culture in vitro and teratomas after injection into SCID mice, and differentiated further into derivatives of all three germ layers. Under conditions of committed differentiation, these human ESCs could differentiate into retinal pigment epithelium cells after 2 months in culture. CONCLUSIONS: The results of this study demonstrated that human foreskin/abdominal fibroblasts have the potential to support the derivation and long-term culture of human ESCs, which can then be used to generate retinal pigment epithelium cells with characteristic morphology and molecular markers. This technique avoids the concerns of contamination from animal feeder layers during human ESC derivation, culture and differentiation, and will thus facilitate the development of retinal pigment epithelium cell transplantation therapy.


Assuntos
Diferenciação Celular , Células-Tronco Embrionárias/citologia , Células Alimentadoras/metabolismo , Fibroblastos/metabolismo , Cultura Primária de Células/métodos , Epitélio Pigmentado da Retina/citologia , Animais , Biomarcadores/metabolismo , Blastocisto/citologia , Linhagem Celular , Criança , Pré-Escolar , Meios de Cultura/metabolismo , Células-Tronco Embrionárias/metabolismo , Prepúcio do Pênis/citologia , Camadas Germinativas/citologia , Camadas Germinativas/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Epitélio Pigmentado da Retina/metabolismo , Pele/citologia , Pele/metabolismo , Teratoma/metabolismo , Teratoma/patologia
14.
Oncol Rep ; 27(5): 1587-91, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22344746

RESUMO

Ovarian cancer is the fifth most common cancer among women worldwide. Detection of metastasis of ovarian cancer is crucial for diagnosis and prolongs the life of patients. This study focused on whether SNAI1 overexpression relates to invasion of ovarian cancer in vitro and in vivo. Invasion, colony formation and wound healing assays and flow cytometric analysis were performed to test the invasion and proliferation of SKOV3 ovarian cancer cells after transfection. The effect of SNAI1 on ovarian cancer in vivo was validated using a murine xenograft model. In vitro, SNAI1 upregulation led to an increased percent of CD133+ SKOV3 cells and promoted SKOV3 cell invasion and proliferation. In vivo, the SNAI1 overexpression group showed the highest rate of tumor growth compared with SNAI2 and the control group (60 and 50%, respectively). Our results show that SNAI1 expression induces an increase in the number of CD133+ cells, a change important for the epithelial to mesenchymal transition and the proliferation in ovarian cancer. It is suggested that SNAI1 may serve as a novel target for ovarian cancer prediction and therapy.


Assuntos
Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Fatores de Transcrição/genética , Antígeno AC133 , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Feminino , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Glicoproteínas/genética , Glicoproteínas/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias Ovarianas/metabolismo , Peptídeos/genética , Peptídeos/metabolismo , Fatores de Transcrição da Família Snail , Fatores de Transcrição/metabolismo , Transplante Heterólogo
15.
Chem Pharm Bull (Tokyo) ; 56(2): 217-21, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18239314

RESUMO

Six new tetramic acids derivatives, penicillenols A(1), A(2), B(1), B(2), C(1), and C(2) (1-6), together with citrinin, phenol A acid, phenol A, and dihydrocitrinin, were identified from Penicillium sp. GQ-7, an endophytic fungus associated with Aegiceras corniculatum. Their structures were elucidated on the basis of comprehensive spectral analysis. All the new compounds were evaluated for their cytotoxic effects on four cell lines by the MTT method. Penicillenols A(1) and B(1) showed cytotoxicities against HL-60 cell line with IC(50) values of 0.76 microM and 3.20 microM, respectively.


Assuntos
Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Penicillium/química , Primulaceae/microbiologia , Pirrolidinonas/isolamento & purificação , Pirrolidinonas/farmacologia , Cromatografia Líquida de Alta Pressão , Ensaios de Seleção de Medicamentos Antitumorais , Fermentação , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Ultravioleta , Sais de Tetrazólio , Tiazóis
16.
J Nat Prod ; 71(4): 543-6, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18281952

RESUMO

In order to search for structurally novel and bioactive natural compounds from microorganisms, a halotolerant fungal strain, Penicillium citrinum B-57, which mainly produces citrinin derivatives, was isolated from sediments collected from the Jilantai salt field. From the ethyl acetate extract of P. citrinum B-57, two new citrinin dimers, pennicitrinone C ( 1) and penicitrinol B ( 2), and 11 known related compounds were isolated and identified by spectroscopic and chemical methods. These compounds showed antioxidative activity against DPPH radicals with IC 50 values ranging from 0.8 to 59 microM.


Assuntos
Antioxidantes/isolamento & purificação , Citrinina/isolamento & purificação , Penicillium/química , Antioxidantes/química , Antioxidantes/farmacologia , Compostos de Bifenilo , China , Citrinina/análogos & derivados , Citrinina/química , Citrinina/farmacologia , Estrutura Molecular , Picratos/farmacologia
17.
Chem Biodivers ; 4(12): 2913-9, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18081101

RESUMO

During our search for novel antitumor lead compounds from microorganisms living under extreme conditions, three novel alkaloids, variecolortides A-C (1-3), were isolated from the mycelia of the halotolerant fungal strain Aspergillus variecolor B-17. The new compounds were found to share an unprecedented 'spiro-anthronopyranoid diketopiperazine' structure, with a stable hemiaminal function, as corroborated by in-depth NMR-spectroscopic and mass-spectrometric analyses, as well as by a single-crystal X-ray analysis of 1. All compounds were shown to exhibit weak cytotoxic and antioxidant activities.


Assuntos
Alcaloides/química , Alcaloides/isolamento & purificação , Aspergillus/química , Resistência a Medicamentos/efeitos dos fármacos , Compostos Macrocíclicos/química , Sais/farmacologia , Compostos de Espiro/química , Alcaloides/toxicidade , Aspergillus/classificação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Compostos Macrocíclicos/toxicidade , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular , Neoplasias/patologia , Compostos de Espiro/toxicidade
18.
Cell Res ; 17(10): 858-68, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17893708

RESUMO

RIG-I (retinoid acid-inducible gene-I), a putative RNA helicase with a cytoplasmic caspase-recruitment domain (CARD), was identified as a pattern-recognition receptor (PRR) that mediates antiviral immunity by inducing type I interferon production. To further study the biological function of RIG-I, we generated Rig-I(-/-) mice through homologous recombination, taking a different strategy to the previously reported strategy. Our Rig-I(-/-) mice are viable and fertile. Histological analysis shows that Rig-I(-/-) mice develop a colitis-like phenotype and increased susceptibility to dextran sulfate sodium-induced colitis. Accordingly, the size and number of Peyer's patches dramatically decreased in mutant mice. The peripheral T-cell subsets in mutant mice are characterized by an increase in effector T cells and a decrease in naive T cells, indicating an important role for Rig-I in the regulation of T-cell activation. It was further found that Rig-I deficiency leads to the downregulation of G protein alpha i2 subunit (G alpha i2) in various tissues, including T and B lymphocytes. By contrast, upregulation of Rig-I in NB4 cells that are treated with ATRA is accompanied by elevated G alpha i2 expression. Moreover, G alpha i2 promoter activity is increased in co-transfected NIH3T3 cells in a Rig-I dose-dependent manner. All these findings suggest that Rig-I has crucial roles in the regulation of G alpha i2 expression and T-cell activation. The development of colitis may be, at least in part, associated with downregulation of G alpha i2 and disturbed T-cell homeostasis.


Assuntos
Colite/genética , RNA Helicases DEAD-box/genética , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/genética , Animais , Apoptose/genética , Apoptose/fisiologia , Northern Blotting , Western Blotting , Células Cultivadas , Colite/induzido quimicamente , Colite/patologia , Proteína DEAD-box 58 , RNA Helicases DEAD-box/metabolismo , RNA Helicases DEAD-box/fisiologia , Sulfato de Dextrana/toxicidade , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/metabolismo , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/fisiologia , Camundongos , Camundongos Knockout , Células NIH 3T3 , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T/citologia , Linfócitos T/metabolismo
19.
J Nat Prod ; 70(10): 1558-64, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17896816

RESUMO

Twelve new compounds, variecolorins A-L ( 1- 12), together with eleven known analogues ( 13- 23) were isolated from the broth of a halotolerant fungus, Aspergillus variecolor. The structures of compounds 1- 12 were determined by chemical and spectroscopic methods. Compounds 1- 11, 13- 15, and 20- 23 exhibited weak radical scavenging activity against DPPH, with IC 50 values from 43 to 103 microM. The new compounds 1- 12 all were essentially nontoxic against the P388, HL-60, BEL-7402, and A-549 cell lines with IC 50 values from 70 to 260 microM.


Assuntos
Alcaloides/isolamento & purificação , Aspergillus/química , Sequestradores de Radicais Livres/isolamento & purificação , Alcaloides/química , Alcaloides/farmacologia , Animais , Compostos de Bifenilo , China , Ensaios de Seleção de Medicamentos Antitumorais , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Concentração Inibidora 50 , Estrutura Molecular , Picratos/farmacologia , Salinidade
20.
Blood ; 110(3): 870-6, 2007 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-17431131

RESUMO

Palladin was originally found up-regulated with NB4 cell differentiation induced by all-trans retinoic acid. Disruption of palladin results in neural tube closure defects, liver herniation, and embryonic lethality. Here we further report that Palld(-/-) embryos exhibit a significant defect in erythropoiesis characterized by a dramatic reduction in definitive erythrocytes derived from fetal liver but not primitive erythrocytes from yolk sac. The reduction of erythrocytes is accompanied by increased apoptosis of erythroblasts and partial blockage of erythroid differentiation. However, colony-forming assay shows no differences between wild-type (wt) and mutant fetal liver or yolk sac in the number and size of colonies tested. In addition, Palld(-/-) fetal liver cells can reconstitute hematopoiesis in lethally irradiated mice. These data strongly suggest that deficient erythropoiesis in Palld(-/-) fetal liver is mainly due to a compromised erythropoietic microenvironment. As expected, erythroblastic island in Palld(-/-) fetal liver was found disorganized. Palld(-/-) fetal liver cells fail to form erythroblastic island in vitro. Interestingly, wt macrophages can form such units with either wt or mutant erythroblasts, while mutant macrophages lose their ability to bind wt or mutant erythroblasts. These data demonstrate that palladin is crucial for definitive erythropoiesis and erythroblastic island formation and, especially, required for normal function of macrophages in fetal liver.


Assuntos
Proteínas do Citoesqueleto/deficiência , Eritroblastos/metabolismo , Eritropoese/genética , Fígado/embriologia , Fosfoproteínas/deficiência , Animais , Apoptose/genética , Diferenciação Celular/genética , Ensaio de Unidades Formadoras de Colônias , Perda do Embrião/genética , Perda do Embrião/metabolismo , Perda do Embrião/patologia , Eritroblastos/patologia , Feto/metabolismo , Feto/patologia , Hematopoese Extramedular/genética , Fígado/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Defeitos do Tubo Neural/genética , Defeitos do Tubo Neural/metabolismo , Defeitos do Tubo Neural/patologia , Saco Vitelino/embriologia , Saco Vitelino/metabolismo
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