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1.
Proc Natl Acad Sci U S A ; 121(12): e2310866121, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38483996

RESUMO

Lymphocyte activation gene-3 (LAG-3) is an inhibitory receptor expressed on activated T cells and an emerging immunotherapy target. Domain 1 (D1) of LAG-3, which has been purported to directly interact with major histocompatibility complex class II (MHCII) and fibrinogen-like protein 1 (FGL1), has been the major focus for the development of therapeutic antibodies that inhibit LAG-3 receptor-ligand interactions and restore T cell function. Here, we present a high-resolution structure of glycosylated mouse LAG-3 ectodomain, identifying that cis-homodimerization, mediated through a network of hydrophobic residues within domain 2 (D2), is critically required for LAG-3 function. Additionally, we found a previously unidentified key protein-glycan interaction in the dimer interface that affects the spatial orientation of the neighboring D1 domain. Mutation of LAG-3 D2 residues reduced dimer formation, dramatically abolished LAG-3 binding to both MHCII and FGL1 ligands, and consequentially inhibited the role of LAG-3 in suppressing T cell responses. Intriguingly, we showed that antibodies directed against D1, D2, and D3 domains are all capable of blocking LAG-3 dimer formation and MHCII and FGL-1 ligand binding, suggesting a potential allosteric model of LAG-3 function tightly regulated by dimerization. Furthermore, our work reveals unique epitopes, in addition to D1, that can be targeted for immunotherapy of cancer and other human diseases.


Assuntos
Antígenos de Histocompatibilidade Classe II , Linfócitos T , Animais , Humanos , Camundongos , Dimerização , Fibrinogênio/metabolismo , Ligantes , Mutação
2.
Skeletal Radiol ; 52(8): 1485-1491, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36752828

RESUMO

OBJECTIVE: The ulnar positive variance (UPV) can be observed on simple radiography due to a triangular fibrocartilage complex (TFCC) foveal tear. This study investigated to identify how much radiographic UPV occurs due to a TFCC foveal tear, which may be misdiagnosed as an ulnar impaction syndrome (UIS). MATERIALS AND METHODS: One hundred forty patients who underwent arthroscopic transosseus TFCC foveal repair from March 2013 to March 2019 in our institution were enrolled in this study. Ulnar variances were measured in preoperative, postoperative 6 weeks, 1-year follow-up wrist posteroanterior (PA) radiograph, and power grip PA radiograph of the affected wrist and were compared with those of the same patient's unaffected wrist. RESULTS: In the neutral wrist PA radiograph, ulnar variance increased by 0.56 mm (p < 0.001) after TFCC foveal tear compared to the unaffected side. In the power grip view, ulnar variance also increased by 0.39 mm (p < 0.001) in the affected wrist. The preoperative ulnar positive variance was reduced after an arthroscopic transosseous TFCC foveal repair from 0.56 to 0 mm (p < 0.001). No significant statistical difference was observed between an Atzei class 2 and 3 TFCC tear (0.56 mm vs. 0.41 mm, p = 0.263). CONCLUSION: This study revealed that TFCC foveal tear induces 0.56 mm of radiologic UPV, which was successfully corrected after arthroscopic transosseous TFCC foveal repair. Therefore, UPV associated with TFCC foveal tear should not be misdiagnosed as an UIS. Also, when ulnar shortening osteotomy is planned in case of UIS combined with TFCC foveal tear, the amount of UPV induced by TFCC foveal tear should be considered to prevent over-shortening.


Assuntos
Doenças das Cartilagens , Artropatias , Fibrocartilagem Triangular , Traumatismos do Punho , Humanos , Artroscopia , Fibrocartilagem Triangular/diagnóstico por imagem , Fibrocartilagem Triangular/cirurgia , Articulação do Punho , Traumatismos do Punho/diagnóstico por imagem , Traumatismos do Punho/cirurgia
3.
Food Sci Anim Resour ; 44(5): 1126-1141, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39246537

RESUMO

Antioxidant activity of freeze-dried paprika powder and storage properties of emulsion-type pork sausages containing diverse concentrations of this powder (0%, 1%, 2%, and 3%) were analyzed. Antioxidant activities of red and yellow paprika powders were analyzed by evaluating their 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidant power (FRAP), total phenol content (TPC), and total flavonoid content (TFC). The yellow paprika powder exhibited remarkably higher DPPH radical scavenging activity, FRAP values, and TPC than the red paprika powder (p<0.05), while TFC showed no remarkable difference between them (p>0.05). Storage properties of sausages containing the yellow paprika powder were analyzed by evaluating their water holding capacity, cooking yield, and thiobarbituric acid reactive substance (TBARS), and volatile basic nitrogen (VBN) values. The 3% yellow paprika powder group showed remarkably higher water-holding capacity and cooking yield compared to the 0% group (p<0.05). TBARS values were remarkably lower in the 2% and 3% yellow paprika powder groups than in the 0% group at all weeks (p<0.05). VBN value was remarkably lower in the 3% yellow paprika powder group than in the 0% group at all weeks (p<0.05). Overall, addition of 3% yellow paprika powder improved the storage properties of emulsion-type sausages.

4.
Front Immunol ; 15: 1415102, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39007132

RESUMO

Human regulatory T cells (Treg) suppress other immune cells. Their dysfunction contributes to the pathophysiology of autoimmune diseases, including type 1 diabetes (T1D). Infusion of Tregs is being clinically evaluated as a novel way to prevent or treat T1D. Genetic modification of Tregs, most notably through the introduction of a chimeric antigen receptor (CAR) targeting Tregs to pancreatic islets, may improve their efficacy. We evaluated CAR targeting of human Tregs to monocytes, a human ß cell line and human islet ß cells in vitro. Targeting of HLA-A2-CAR (A2-CAR) bulk Tregs to HLA-A2+ cells resulted in dichotomous cytotoxic killing of human monocytes and islet ß cells. In exploring subsets and mechanisms that may explain this pattern, we found that CD39 expression segregated CAR Treg cytotoxicity. CAR Tregs from individuals with more CD39low/- Tregs and from individuals with genetic polymorphism associated with lower CD39 expression (rs10748643) had more cytotoxicity. Isolated CD39- CAR Tregs had elevated granzyme B expression and cytotoxicity compared to the CD39+ CAR Treg subset. Genetic overexpression of CD39 in CD39low CAR Tregs reduced their cytotoxicity. Importantly, ß cells upregulated protein surface expression of PD-L1 and PD-L2 in response to A2-CAR Tregs. Blockade of PD-L1/PD-L2 increased ß cell death in A2-CAR Treg co-cultures suggesting that the PD-1/PD-L1 pathway is important in protecting islet ß cells in the setting of CAR immunotherapy. In summary, introduction of CAR can enhance biological differences in subsets of Tregs. CD39+ Tregs represent a safer choice for CAR Treg therapies targeting tissues for tolerance induction.


Assuntos
Apirase , Receptores de Antígenos Quiméricos , Linfócitos T Reguladores , Humanos , Apirase/imunologia , Apirase/metabolismo , Linfócitos T Reguladores/imunologia , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/metabolismo , Citotoxicidade Imunológica , Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/metabolismo , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/terapia , Antígeno HLA-A2/imunologia , Antígeno HLA-A2/genética , Antígeno HLA-A2/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Células Secretoras de Insulina/imunologia , Células Secretoras de Insulina/metabolismo , Antígenos CD
5.
Nanoscale Adv ; 5(4): 1070-1078, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36798505

RESUMO

The micropipette, pencil-shaped with an aperture diameter of a few micrometers, is a potentially promising tool for the three-dimensional (3D) printing of individual microstructures based on its capability to deliver low volumes of nanomaterial solution on a desired spot resulting in micro/nanoscale patterning. Here, we demonstrate a direct 3D printing technique in which a micropipette with a cadmium selenide (CdSe) quantum dot (QD) solution is guided by an atomic force microscope with no electric field and no piezo-pumping schemes. We define the printed CdSe QD wires, which are a composite material with a QD-liquid coexistence phase, by using photoluminescence and Raman spectroscopy to analyze their intrinsic properties and additionally demonstrate a means of directional falling.

6.
Nano Converg ; 10(1): 57, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38102309

RESUMO

Spatial manipulation of excitonic quasiparticles, such as neutral excitons, charged excitons, and interlayer excitons, in two-dimensional semiconductors offers unique capabilities for a broad range of optoelectronic applications, encompassing photovoltaics, exciton-integrated circuits, and quantum light-emitting systems. Nonetheless, their practical implementation is significantly restricted by the absence of electrical controllability for neutral excitons, short lifetime of charged excitons, and low exciton funneling efficiency at room temperature, which remain a challenge in exciton transport. In this comprehensive review, we present the latest advancements in controlling exciton currents by harnessing the advanced techniques and the unique properties of various excitonic quasiparticles. We primarily focus on four distinct control parameters inducing the exciton current: electric fields, strain gradients, surface plasmon polaritons, and photonic cavities. For each approach, the underlying principles are introduced in conjunction with its progression through recent studies, gradually expanding their accessibility, efficiency, and functionality. Finally, we outline the prevailing challenges to fully harness the potential of excitonic quasiparticles and implement practical exciton-based optoelectronic devices.

7.
Dev Reprod ; 24(3): 159-165, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33110947

RESUMO

Previously, we reported adverse effects of low-dose nonylphenol (NP) exposure on the reproductive parameters of F1 female mice. In the present study we further investigated the pathohistological effect of NP exposure on the reproductive organs in F1 female mice. NP exposures were continuously conducted from parental pre-mating period until the postnatal day (PND) 33 of F1 offspring for vaginal examination. Mice were sacrificed on PND 30 and the reproductive tissue weights were measured. The initial (at PND 21) body weights of the NP-50 group animals were significantly lower than those of control group animals, and the weight deficit were recovered when the terminal (PND 33) body weights were measured. Early vaginal opening was found in NP group animals (p<0.05). Pathohistological studies revealed that NP-treated F1 animals showed prominent increase in the ovarian follicle numbers (p<0.01), and decrease in the diameter of uterine myometrium (p<0.01), and increase in the diameter of luminal epithelium (p<0.05). The present study demonstrated that the subchronic low-dose NP exposure induced early beginning of puberty and pathohistological abnormalities in ovary and uterus of F1 mice. Further studies are needed to achieve a better understanding on the action mechanism of NP in pubertal onset and to find a way to avoid a hazardous situation provoked by NP exposure.

8.
Nucleic Acids Res ; 35(Web Server issue): W701-6, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17586823

RESUMO

ProSight PTM 2.0 (http://prosightptm2.scs.uiuc.edu) is the next generation of the ProSight PTM web-based system for the identification and characterization of proteins using top down tandem mass spectrometry. It introduces an entirely new data-driven interface, integrated Sequence Gazer for protein characterization, support for fixed modifications, terminal modifications and improved support for multiple precursor ions (multiplexing). Furthermore, it supports data import and export for local analysis and collaboration.


Assuntos
Biologia Computacional/métodos , Espectrometria de Massas/métodos , Proteínas/química , Software , Bases de Dados de Proteínas , Processamento Eletrônico de Dados , Humanos , Internet , Polimorfismo Genético , Linguagens de Programação , Processamento de Proteína Pós-Traducional , Proteínas/análise , Proteínas/genética , Análise de Sequência de Proteína , Sitios de Sequências Rotuladas , Interface Usuário-Computador
9.
Dev Reprod ; 23(2): 93-99, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31321349

RESUMO

Nonylphenols (NPs) are widely used industrial materials, and are considered as potent endocrine disrupting chemical. Present study was undertaken to clarify the effect of subchronic low-dose NP exposure to F1 generation male mice. Mice were divided into 2 groups; (1) CON, control animals and (2) NP-50 (50 µg/L), animals were treated with NP via drinking water. NP exposures were continuously conducted from parental pre-mating period until the postnatal day (PND) 55 of F1 offsprings. Mice were sacrificed on PND 55 and the tissue weights were measured. The initial body weights (at PND 21) and terminal body weights (PND 55) of the NP-50 animals were significantly lower than those of control animals (p<0.05). NP exposure induced a significant increase in the absolute weight of the testes (p<0.05). Conversely, the NP exposure caused significant decrease in the absolute weights of the epididymis (p<0.01), prostate (p<0.05) and seminal vesicle (p<0.05). Histopathological studies revealed that NP-treated animals exerted decreased seminiferous tubule diameters, reduced luminal area, and lower number of germ cells. Also some sloughing morphologies in the tubules were observed. In the caudal epididymis, fewer mature sperms and swollen epithelial cells were found in the NP-treated group. Our results confirmed that the subchronic low-dose NP exposure altered some male parameters and induced histopathological abnormalities in testis and epididymis of F1 mice. Since the NP dose used in this study is close to the average human daily NP exposure, our results could provide practically meaningful understanding of adverse effect of EDC in human.

10.
Dev Reprod ; 23(3): 255-262, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31660452

RESUMO

Previously, we reported negative effects of low-dose nonylphenol (NP) exposure on the reproductive organs of F1 male mice. In the present study was further investigated the endocrine disrupting effect of NP exposure to F2 generation male mice. Mice were divided into 2 groups; (1) CON, control animals and (2) NP-50 (50 µg/L), animals were treated with NP via drinking water. NP exposures were continuously conducted from parental pre-mating period until the postnatal day (PND) 55 of F2 offsprings. Mice were sacrificed on PND 55 and the reproductive tissue weights were measured. The initial (at PND 21) and terminal (PND 55) body weights of the NP-50 group animals were not significantly different from those of control group animals. NP exposure fail to induce a significant weight change of the testes, seminal vesicle and prostate except absolute epididymal weight (p<0.05). However, pathohistological studies revealed that NP-treated F2 animals showed evident decrease in seminiferous tubule diameters, reduced luminal area and number of germ cells. Also, sloughing morphologies in the tubules were notable. In the caudal epididymis, fewer mature sperms and swollen epithelial cells were found in the NP-treated group. The present study demonstrated that the subchronic low-dose NP exposure induced pathohistological abnormalities in testis and epididymis of F2 mice, and we assumed that these 'qualitative' changes in reproductive tissues could be derived from the epigenetic modifications such as DNA methylation, histone modification, altered DNA accessibility and chromatin structure. Further studies are needed to achieve a better understanding on the multi- or trans-generational effects of NP on the reproductive health and a human application.

11.
Dev Reprod ; 21(2): 151-156, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28785736

RESUMO

High-fructose corn syrup (HFCS) is widely used as sweetener, and its overconsumption is become a major health problem. In the present study, we used adult female rats and applied a 28 days HFCS feeding model to monitor the estrous cycle and changes in tissue weights and histology. Adult female rats were divided into three groups. Animals were fed with ad libitum normal chow and (1) 24 hours tap water (Control group), (2) 12 hours HFCS access during dark period and 12 hours tap water (12H group), and (3) 24 hours HFCS only access (24H group). Total exposure period was 28 days. There is no significant change in body weight between control and HFCS-fed animals. Both absolute and relative weights of ovary in 24H animals were significantly heavier than those in control or 12H animals. The absolute and relative weights of the kidney and liver in 24H groups were significantly heavier than those in control or 12H animals. The estrous cycles of the 24H animals were significantly longer. Histological analyses revealed that 24H ovaries were relatively bigger and possessed more corpus lutea than control ovaries. Uterine sections of 12H and 24H animals showed a well-developed stratum vasculare between inner and outer myometrial layers. The number of endometrial glands were decreased in 12H uteri, and recovered in 24H uteri compared to control. Numbers of convoluted tubule in distal region increased in 12H and 24H kidney samples. Liver specimens of 12H and 24H showed the increased number of fat containing vacuoles. In conclusion, our study demonstrated that HFCS treatment for 28 days could induce (1) changes in length of estrous cycle with extended estrous and diestrous stages, (2) altered ovarian and uterine histology, and (3) liver and renal lipid accumulation. These findings reveal the adverse effects of HFCS drinking on the reproductive function and lipid metabolism of female rats.

12.
Dev Reprod ; 21(4): 441-448, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29354789

RESUMO

Bisphenol-A(BPA) is a member of alkylphenol family, and shows adverse effects including reduced fertility, reproductive tract abnormalities, metabolic disorder, cancer induction, neurotoxicity and immunotoxicity. In the present study, we conducted Hershberger assay to evaluate whether the two candidates to replace BPA have androgenic or antiandrogenic activity. The assay was carried out using immature castrated Sprague-Dawley male rats. After 7 days of the surgery, testosterone propionate (TP, 0.4 mg/kg/day) and test materials (low dose, 40 mg/kg/day; high dose, 400 mg/kg/day) were administered for 10 consecutive days by subcutaneous (s.c.) injection and oral gavage, respectively. Test materials were BPA, isosorbide (ISO) and cyclohexanedimethanol (CHDM). The rats were necropsied, and then the weights of five androgen-dependent tissues [ventral prostate, seminal vesicle, levator ani-bulbocavernosus (LABC) muscle, paired Cowper's glands, and glans penis] and three androgen-insensitive tissues (kidney, spleen and liver) were measured. All test materials including BPA did not exhibit any androgenic activity in the assay. On the contrary, antiandrogen-like activities were found in all test groups, and the order of the intensity was CHDM > BPA > ISO in the five androgen-sensitive tissues. There was no statistical difference between low dose treatment and high dose treatment of BPA group as well as ISO group. In CHDM group, high dose treatment exhibited most severe weight reduction in all measured tissues. There was no statistical difference in androgen-insensitive tissue measurements, except BPA groups. Since the effects of ISO treatment on the accessory sex organs were much less or not present at all when compared to those of BPA, ISO could be a strong candidate to replace BPA. CHDM treatment brought most severe weight reduction in all of androgen-sensitive tissues, so this material should be excluded for further screening of BPA substitute selection.

13.
Nucleic Acids Res ; 32(Web Server issue): W340-5, 2004 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15215407

RESUMO

ProSight PTM (https://prosightptm.scs.uiuc.edu/) is a web application for identification and characterization of proteins using mass spectra data from 'top-down' fragmentation of intact protein ions (i.e. without any tryptic digestion). ProSight PTM has many tools and graphical features to facilitate analysis of single proteins, proteins in mixtures and proteins fragmented in parallel. Sequence databases from across the phylogenetic tree are supported, with a new database strategy of 'shotgun annotation' used to assist characterization of wild-type proteins. During a database search, data from divergent sources regarding potential mass differences such as polymorphisms, alternate splicing and post-translational modifications are utilized. The user can optionally control how much of this biological variability should be searched.


Assuntos
Espectrometria de Massas , Proteínas/química , Software , Processamento Alternativo , Bases de Dados de Proteínas , Humanos , Internet , Polimorfismo Genético , Processamento de Proteína Pós-Traducional , Proteínas/análise , Proteínas/genética , Proteínas Ribossômicas/química , Análise de Sequência de Proteína , Sitios de Sequências Rotuladas , Interface Usuário-Computador
14.
Mol Neurobiol ; 48(1): 232-43, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23595812

RESUMO

Nicastrin (NCT) is a component of the presenilin protein complex, which is involved in the cleavage of ß-amyloid precursor protein (ßAPP) and Notch. The aim of this study was to determine the manner in which overexpression of wild-type human nicastrin (hNCTw) or mutant human nicastrin (hNCTm, D336A/Y337A) regulates brain functions and amyloid precusor protein (APP) processing. For this, we created transgenic (Tg) mice expressing neuron-specific enolase (NSE)-controlled hNCTw or hNCTm and measured their phenotypes as time passed. The NSE/hNCTw and NSE/hNCTm Tg groups exhibited greater behavioral dysfunction from 10 months of age than the non-Tg group, although their severities differed. Further, activity and component levels of the γ-secretase complex were significantly elevated in NSE/hNCTw Tg mice, expect for PEN-2. These alterations induced stimulation of APP processing, resulting in overproduction of Aß-42 peptide in the NSE/hNCTw Tg group, whereas the NSE/hNCTm Tg group showed a comparatively weaker effect. Furthermore, the highest expression levels of ß-secretase and NICD were observed in the NSE/hNCTw Tg group, similar to other phenotypes. Especially, a significances interference on the interaction between NCT and γ-secretase substrates was detected in NSE/hNCTm Tg groups compare with NSE/hNCTw Tg group. These results indicate that hNCTw overexpression in Tg mice promoted active assembly of the γ-secretase complex through modulation of APP processing and behavior, whereas the lesser effect in NSE/hNCTm Tg mice was due to reduced expression of hNCTm. These Tg mice could be useful for the development and application of therapeutic drugs in an animal model of Alzheimer's disease.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Comportamento Animal , Glicoproteínas de Membrana/metabolismo , Processamento de Proteína Pós-Traducional , Animais , Sequência de Bases , Encéfalo/metabolismo , Encéfalo/patologia , Ciclo Celular , Ativação Enzimática , Humanos , Aprendizagem em Labirinto , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Peptídeos/metabolismo , Ratos , Especificidade por Substrato , Transgenes/genética
15.
Neurosci Lett ; 487(1): 123-7, 2011 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-20974223

RESUMO

In the present study, we examined whether aqueous extract of Eucommia ulmoides Oliv. Bark (EUE) with graded doses exerted its neuroprotective effects on amyloid beta(25-35) (Aß(25-35))-induced learning and memory impairments in mice. Mice received a single intracerebroventricular (i.c.v.) injection of Aß(25-35) 6 nmol as the critical factor in Alzheimer's disease (AD), cognition was evaluated using Y-maze, passive avoidance, and Morris water maze tests. EUE significantly improved the Aß(25-35)-induced memory deficit in the Y-maze test. Also, EUE increased step-through latency time with Aß(25-35)-induced learning and memory deficits in the passive avoidance test. In addition, EUE decreased the escape latencies with Aß(25-35)-induced cognitive impairments in the Morris water maze test. In the probe trial session, EUE increased time spent in the target quadrant. In the in vitro study, EUE was found to inhibit acetylcholinesterase (AChE) activity in a dose-dependent manner (IC50 value; 172 µg/ml). Ex vivo study, EUE significantly inhibited AChE activity in the hippocampus and frontal cortex. These results demonstrate that EUE possesses potent neuroprotective effects and that its beneficial effects are mediated, in part, by AChE inhibition, and therefore, might be a potential candidate in neurodegenerative diseases such as AD.


Assuntos
Eucommiaceae , Transtornos da Memória/tratamento farmacológico , Fitoterapia/métodos , Casca de Planta/química , Preparações de Plantas/uso terapêutico , Acetilcolinesterase/metabolismo , Peptídeos beta-Amiloides/toxicidade , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Lobo Frontal/efeitos dos fármacos , Lobo Frontal/enzimologia , Hipocampo/efeitos dos fármacos , Hipocampo/enzimologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/patologia , Camundongos , Camundongos Endogâmicos ICR , Fragmentos de Peptídeos/toxicidade , Tempo de Reação/efeitos dos fármacos , Natação/psicologia
16.
Eur J Pharmacol ; 649(1-3): 210-7, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-20854806

RESUMO

Chlorogenic acid is a major polyphenolic component of many plants and beverages, and is particularly abundant in coffee. We evaluated the neuroprotective effects of chlorogenic acid on learning and memory impairment induced by scopolamine (0.5 mg/kg, i.p.), a muscarinic antagonist, using the Y-maze, passive avoidance, and Morris water maze tests. The chlorogenic acid significantly improved the impairment of short-term or working memory induced by scopolamine in the Y-maze test, and significantly reversed cognitive impairments in mice as measured by the passive avoidance test. In addition, chlorogenic acid decreased escape latencies in the Morris water maze test. In a probe trial session, chlorogenic acid increased the latency time in the target quadrant in a dose-dependent manner. Ex vivo, chlorogenic acid inhibited acetylcholinesterase activity in the hippocampus and frontal cortex. Chlorogenic acid also decreased malondialdehyde levels in the hippocampus and frontal cortex. In vitro, chlorogenic acid was found to inhibit acetylcholinesterase activity (IC50=98.17 µg/ml) and free radical scavenging activity (IC50=3.09 µg/ml) in a dose-dependent manner. These results indicate that chlorogenic acid may exert anti-amnesic activity via inhibition of acetylcholinesterase and malondialdehyde in the hippocampus and frontal cortex.


Assuntos
Amnésia/tratamento farmacológico , Antioxidantes/uso terapêutico , Ácido Clorogênico/uso terapêutico , Inibidores da Colinesterase/uso terapêutico , Deficiências da Aprendizagem/tratamento farmacológico , Antagonistas Muscarínicos/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Acetilcolinesterase , Doença de Alzheimer/tratamento farmacológico , Amnésia/induzido quimicamente , Amnésia/metabolismo , Animais , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Ácido Clorogênico/administração & dosagem , Ácido Clorogênico/farmacologia , Inibidores da Colinesterase/administração & dosagem , Inibidores da Colinesterase/farmacologia , Relação Dose-Resposta a Droga , Reação de Fuga/efeitos dos fármacos , Lobo Frontal/efeitos dos fármacos , Lobo Frontal/enzimologia , Lobo Frontal/metabolismo , Proteínas Ligadas por GPI/antagonistas & inibidores , Hipocampo/efeitos dos fármacos , Hipocampo/enzimologia , Hipocampo/metabolismo , Deficiências da Aprendizagem/induzido quimicamente , Deficiências da Aprendizagem/metabolismo , Masculino , Malondialdeído/metabolismo , Memória de Curto Prazo/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos ICR , Antagonistas Muscarínicos/administração & dosagem , Antagonistas Muscarínicos/farmacologia , Proteínas do Tecido Nervoso/antagonistas & inibidores , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/farmacologia
17.
Mol Cell Proteomics ; 4(7): 1002-8, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15863400

RESUMO

The human proteome is a highly complex extension of the genome wherein a single gene often produces distinct protein forms due to alternative splicing, RNA editing, polymorphisms, and posttranslational modifications. Such biological variation compounded by the high sequence identity within gene families currently overwhelms the complete and routine characterization of mammalian proteins by MS. A new data base of human proteins (and their possible variants) was created and searched using tandem mass spectrometric data from intact proteins. This first application of top down MS/MS to wild-type human proteins demonstrates both gene-specific identification and the unambiguous characterization of multifaceted mass shifts (Deltam values). Such Deltam values found from the precise identification of 45 protein forms from HeLa cells reveal 34 coding single nucleotide polymorphisms, two protein forms from alternative splicing, and 12 diverse modifications (not including simple N-terminal processing), including a previously unknown phosphorylation at 10% occupancy. Automated protein identification was achieved with a median expectation value of 10(-13) and often occurred simultaneously with dissection of diverse sources of protein variability as they occur in combination. Top down MS therefore has a bright future for enabling precise annotation of gene products expressed from the human genome by non-mass spectrometrists.


Assuntos
Processamento Alternativo , Proteínas Nucleares/análise , Polimorfismo de Nucleotídeo Único , Processamento de Proteína Pós-Traducional , Sequência de Aminoácidos , Animais , Biologia Computacional , Bases de Dados de Proteínas , Células HeLa , Humanos , Espectrometria de Massas , Dados de Sequência Molecular , Proteínas Nucleares/genética , Fosfoproteínas/análise , Fosfoproteínas/genética , Proteômica
18.
J Am Chem Soc ; 126(11): 3386-7, 2004 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-15025441

RESUMO

Eukaryotic histones serve as prototypical examples of posttranslational complexity with diverse modifications (PTMs) on many different residues that comprise a "Histone Code". To help crack this code more efficiently, we demonstrate a new strategy for protein characterization wherein complete PTM descriptions are obtained by database retrieval instead of manual interpretation of information-rich data from high-resolution tandem mass spectrometry (MS/MS). A database of nearly 50 000 modified histone H4 sequences was created and queried with 91 fragment ions from electron capture dissociation of a histone form +112 Da (versus unmodified mass) selectively accumulated in a quadrupole Fourier transform hybrid mass spectrometer. The correct form atop the retrieval list indicated dimethylation at Lys20, acetylation at the N terminus, and acetylation at Lys16 (resolved from trimethylation, Deltam = 0.036 Da). A statistical evaluation reveals the critical role of mass accuracy and that PTM "isomers" are retrieved as next-best matches. The applicability of shotgun annotation to forms of H4 with up to six PTMs is demonstrated, with extensibility to other histones (e.g., H2A, H2B, H3) and other protein classes projected.


Assuntos
Histonas/química , Proteômica/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Sequência de Aminoácidos , Bases de Dados de Proteínas , Humanos , Dados de Sequência Molecular , Isoformas de Proteínas
19.
Anal Chem ; 75(16): 4081-6, 2003 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-14632120

RESUMO

For the identification and characterization of proteins harboring posttranslational modifications (PTMs), a "top down" strategy using mass spectrometry has been forwarded recently but languishes without tailored software widely available. We describe a Web-based software and database suite called ProSight PTM constructed for large-scale proteome projects involving direct fragmentation of intact protein ions. Four main components of ProSight PTM are a database retrieval algorithm (Retriever), MySQL protein databases, a file/data manager, and a project tracker. Retriever performs probability-based identifications from absolute fragment ion masses, automatically compiled sequence tags, or a combination of the two, with graphical rendering and browsing of the results. The database structure allows known and putative protein forms to be searched, with prior or predicted PTM knowledge used during each search. Initial functionality is illustrated with a 36-kDa yeast protein identified from a processed cell extract after automated data acquisition using a quadrupole-FT hybrid mass spectrometer. A +142-Da delta(m) on glyceraldehyde-3-phosphate dehydrogenase was automatically localized between Asp90 and Asp192, consistent with its two cystine residues (149 and 153) alkylated by acrylamide (+71 Da each) during the gel-based sample preparation. ProSight PTM is the first search engine and Web environment for identification of intact proteins (https://prosightptm.scs.uiuc.edu/).


Assuntos
Bases de Dados de Proteínas , Espectrometria de Massas/métodos , Processamento de Proteína Pós-Traducional , Proteínas/análise , Software , Sequência de Aminoácidos , Animais , Internet , Dados de Sequência Molecular , Proteínas/química , Proteínas de Saccharomyces cerevisiae/análise , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Análise de Sequência de Proteína , Sitios de Sequências Rotuladas
20.
Proc Natl Acad Sci U S A ; 101(9): 2678-83, 2004 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-14976258

RESUMO

For more complete characterization of DNA-predicted proteins (including their posttranslational modifications) a "top-down" approach using high-resolution tandem MS is forwarded here by its application to methanogens in both hypothesis-driven and discovery modes, with the latter dependent on new automation benchmarks for intact proteins. With proteins isolated from ribosomes and whole-cell lysates of Methanococcus jannaschii (approximately 1,800 genes) using a 2D protein fractionation method, 72 gene products were identified and characterized with 100% sequence coverage via automated fragmentation of intact protein ions in a custom quadrupole/Fourier transform hybrid mass spectrometer. Three incorrect start sites and two modifications were found, with one of each determined for MJ0556, a 20-kDa protein with an unknown methylation at approximately 50% occupancy in stationary phase cells. The separation approach combined with the quadrupole/Fourier transform hybrid mass spectrometer allowed targeted and efficient comparison of histones from M. jannaschii, Methanosarcina acetivorans (largest Archaeal genome, 5.8 Mb), and yeast. This finding revealed a striking difference in the posttranslational regulation of DNA packaging in Eukarya vs. the Archaea. This study illustrates a significant evolutionary step for the MS tools available for characterization of WT proteins from complex proteomes without proteolysis.


Assuntos
Proteínas Arqueais/metabolismo , Mathanococcus/metabolismo , Processamento de Proteína Pós-Traducional , Sequência de Aminoácidos , Proteínas Arqueais/química , Proteínas Arqueais/isolamento & purificação , Automação , Análise de Fourier , Modelos Biológicos , Dados de Sequência Molecular , Peso Molecular
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