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1.
Chemistry ; : e202402886, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39212526

RESUMO

The chemoselective [4+2] annulation/aromatization reactions between benzofuran-derived azadienes and N-Ts cyanamides are developed, affording a convenient method for synthesizing benzofuro[3,2-d]pyrimidin-2-amines under mild conditions. Herein, N-Ts cyanamides participated in reactions selectively via carbodiimide anion intermediates and the corresponding cyanamide anion intermediates derived products were not observed. The proposed chemoselective stepwise reaction mechanism was well supported by DFT calculations.

2.
J Org Chem ; 86(4): 3546-3554, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33538590

RESUMO

The convenient preparation of N2-unprotected five-membered cyclic guanidines was achieved through a cascade [3 + 2] cycloaddition between organo-cyanamides and α-haloamides under mild conditions in good to excellent yields (up to 99%). The corresponding cyclic guanidines could be easily transformed into hydantoins via hydrolysis.


Assuntos
Cianamida , Guanidinas , Reação de Cicloadição , Guanidina , Hidrólise
3.
Breast J ; 27(3): 287-290, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33506606

RESUMO

Atypical ductal hyperplasia (ADH) is an indication for excisional biopsy to rule out occult breast cancer. We analyzed pathological findings on excisional biopsy for ADH diagnosed in a high volume breast center equipped with digital tomosynthesis. Two hundred consecutive patients were diagnosed with ADH on core biopsy with radiographic concordance followed by excisional biopsy. On excisional biopsy, 33 patients (16.5%) were diagnosed with DCIS or invasive breast cancer. Patients with a concurrent diagnosis of papilloma had a higher risk of upstaging on both univariate and multivariate analysis (41.7% vs. 14.9%, p=0.015). No other statistically significant predictors of upgrading were identified (p>0.05).


Assuntos
Neoplasias da Mama , Carcinoma Ductal de Mama , Carcinoma Intraductal não Infiltrante , Biópsia com Agulha de Grande Calibre , Mama/diagnóstico por imagem , Mama/patologia , Mama/cirurgia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/cirurgia , Feminino , Humanos , Hiperplasia/patologia , Resultado do Tratamento
4.
Breast Cancer Res Treat ; 183(3): 771-774, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32705377

RESUMO

PURPOSE: The management of biopsy proven atypical lobular hyperplasia (ALH) is controversial. Although upgrade rates are low, excisional biopsy is often performed to rule out occult breast cancer. METHODS: In this study, we analyzed our experience with excisional biopsy for ALH diagnosed in the digital tomosynthesis era with radiographic concordance in the community hospital setting. This study included 93 consecutive patients diagnosed with pure ALH on core biopsy from January 2013-December 2017 who underwent subsequent excisional biopsy. Potential clinical, radiographic and pathologic predictors of upgrading were analyzed. RESULTS: At the time of excisional biopsy, five patients (5.4%) were upgraded to DCIS or invasive breast cancer. There was also a trend towards higher upgrade rates in patients with contralateral breast cancer (p = 0.06), biopsy performed by ultrasound or MRI (p = 0.07) and extensive ALH (p = 0.10). Other clinical, radiographic and pathologic variables were not predictive of upgrade rate (p > 0.1 for all). CONCLUSION: Patients with pure ALH with radiographic concordance have a low risk of pathologic upgrading on excisional biopsy. Potential predictors of upgrade rate warrant further analysis in a larger dataset.


Assuntos
Neoplasias da Mama , Carcinoma in Situ , Carcinoma Lobular , Biópsia com Agulha de Grande Calibre , Mama/diagnóstico por imagem , Mama/patologia , Mama/cirurgia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Carcinoma in Situ/patologia , Carcinoma Lobular/diagnóstico por imagem , Carcinoma Lobular/epidemiologia , Feminino , Hospitais Comunitários , Humanos , Hiperplasia/patologia
5.
Zhonghua Nan Ke Xue ; 26(10): 900-905, 2020 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-33382221

RESUMO

OBJECTIVE: To analyze the relationship of Mycoplasma genitalium (MG) infection with routine semen parameters and sperm DNA integrity in male infertility patients. METHODS: Totally, 114 semen samples, 34 MG-positive and 80 MG-negative, were collected from male infertility patients and subjected to routine semen analysis with the computer-assisted sperm analysis system, Papanicolaou staining for observation of sperm morphology, and sperm chromatin diffusion (SCD) test for detection of sperm DNA integrity. Semen parameters and DNA integrity were compared between the MG-positive and MG-negative groups with SPSS 21.0 statistical software and the relationship between the semen parameters and DNA integrity analyzed by Pearson correlation analysis. RESULTS: The MG-positive samples, compared with the MG-negative ones, showed significantly decreased semen volume (ï¼»2.87 ± 0.37ï¼½ vs ï¼»3.86 ± 0.43ï¼½ ml, P < 0.01), sperm concentration (ï¼»29.05 ± 6.17ï¼½ vs ï¼»32.56 ± 5.97ï¼½ ×106/ml, P < 0.01), and percentages of progressively motile sperm (PMS) (ï¼»15.86 ± 2.79ï¼½% vs ï¼»23.65 ± 3.47ï¼½%, P < 0.01) and morphologically normal sperm (MNS) (ï¼»6.35 ± 2.06ï¼½% vs ï¼»7.14 ± 1.89ï¼½%, P < 0.05), increased proportions of non-halo sperm (ï¼»15.02 ± 3.52ï¼½% vs ï¼»9.72 ± 2.94ï¼½%, P <0.01) and small-halo sperm (ï¼»16.37 ± 5.26ï¼½% vs ï¼»11.07 ± 1.65ï¼½%, P < 0.01) and sperm DNA fragmentation index (DFI) (ï¼»31.39 ± 3.16ï¼½% vs ï¼»20.79 ± 3.59ï¼½%, P < 0.01), and reduced proportion of large-halo sperm (ï¼»54.75 ± 8.74ï¼½% vs ï¼»64.15 ± 9.76ï¼½%, P < 0.01). DFI was negatively correlated with the percentages of PMS (r = -0.516, P < 0.05) and MNS (r = -0.429, P < 0.05) in the MG-positive group, but not correlated with any of the routine semen parameters in the MG-negative patients (P > 0.05). CONCLUSIONS: MG infection may be an important factor affecting sperm quality in male infertility patients. Active prevention and treatment of MG infection can help prevent male infertility.


Assuntos
Fragmentação do DNA , Infertilidade Masculina , Infecções por Mycoplasma , Humanos , Infertilidade Masculina/genética , Infertilidade Masculina/microbiologia , Masculino , Infecções por Mycoplasma/complicações , Mycoplasma genitalium , Sêmen , Análise do Sêmen , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides
6.
Org Biomol Chem ; 17(41): 9200-9208, 2019 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-31596301

RESUMO

A highly efficient domino aza-MIRC (Michael Induced Ring Closure) reaction between barbiturate-derived alkenes and N-alkoxy α-haloamides has been achieved in moderate to excellent yields. This reaction proceeds smoothly under mild conditions via a domino aza-Michael addition/intramolecular SN2 sequence, providing a practical tool in the synthesis of bioactive molecules spirobarbiturate-3-pyrrolidinones.

7.
BMC Urol ; 18(1): 31, 2018 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-29739388

RESUMO

BACKGROUND: The indication of retroperitoneal laparoscopic adrenalectomy (RLA) was extended with the retroperitoneal approach and has been wildly accepted and technologically matured. However, the management of large adrenal tumors via this approach still remains controversial. The aim of this study was to perform a comprehensive analysis on the minimally invasive surgical management of larger adrenal tumors. METHODS: A total of 78 patients with large adrenal tumors (> 5 cm) and 97 patients with smaller adrenal tumors (< 5 cm) were enrolled in this study. The patient characteristics were preferentially analyzed. The intra-operative and postoperative indicators were compared between those who underwent RLA and those who underwent transperitoneal laparoscopic adrenalectomy (TLA); the intra-operative and postoperative indicators were also compared between the large tumor group and smaller tumor group of those who underwent RLA. Furthermore, the analyses of partial RLA were focused on the perioperative indicators and follow-up results. RESULTS: RLA was superior to TLA in terms of operation time (98.71 ± 32.30 min vs. 124.36 ± 34.62 min, respectively, P = 0.001), hospitalization duration (7.43 ± 2.82 days vs. 8.91 ± 3.40 days, respectively, P = 0.04), duration of drain (4.83 ± 0.37 days vs. 3.94 ± 2.21 days, respectively, P = 0.02), first oral intake (2.82 ± 0.71 days vs. 1.90 ± 0.83 days, respectively, P < 0.001) and time to ambulation (3.89 ± 1.64 days vs. 2.61 ± 1.42 days, respectively, P < 0.001). Further analyses of the RLA patients demonstrated that the larger tumor (> 5 cm) group showed superior results for the intraoperative indicators than the smaller tumor (< 5 cm) group (P < 0.05), while the results for the postoperative indicators between the two tumor size groups were similar (P > 0.05). Data confirmed that the partial resection method was superior to the total resection method from the perspective of the hormone supplement (0% vs. 48.15%, P = 0.002). The 2-year recurrence-free rates were 92.60 and 92.86% for the total and partial RLA resection methods, respectively (P = 0.97). The partial RLA resection method had a similar complete remission rate as the total RLA resection method (96.30% vs. 100%, respectively, P = 0.47). CONCLUSION: Both RLA and TLA seem to provide similar effects for the surgical management of large adrenal tumors. However, partial RLA resection should be considered for the management of benign tumors to reduce the hormone supplement.


Assuntos
Neoplasias das Glândulas Suprarrenais/cirurgia , Adrenalectomia/métodos , Gerenciamento Clínico , Laparoscopia/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Assistência Perioperatória/métodos , Neoplasias das Glândulas Suprarrenais/diagnóstico , Adrenalectomia/tendências , Adulto , Idoso , Feminino , Seguimentos , Humanos , Laparoscopia/tendências , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/tendências , Assistência Perioperatória/tendências , Fatores de Tempo , Resultado do Tratamento
8.
Bioorg Med Chem Lett ; 27(4): 1003-1006, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28087273

RESUMO

The covalently cross-linked chitosan-poly(ethylene glycol)1540 derivatives have been developed as a controlled release system with potential for the delivery of protein drug. The swelling characteristics of the hydrogels based on these derivatives as the function of different PEG content and the release profiles of a model protein (bovine serum albumin, BSA) from the hydrogels were evaluated in simulated gastric fluid with or without enzyme in order to simulate the gastrointestinal tract conditions. The derivatives cross-linked with difunctional PEG1540-dialdehyde via reductive amination can swell in alkaline pH and remain insoluble in acidic medium. The cumulative release amount of BSA was relatively low in the initial 2h and increased significantly at pH 7.4 with intestinal lysozyme for additional 12h. The results proved that the release-and-hold behavior of the cross-linked CS-PEG1540H-CS hydrogel provided a swell and intestinal enzyme controlled release carrier system, which is suitable for oral protein drug delivery.


Assuntos
Aldeídos/química , Aminas/química , Quitosana/química , Portadores de Fármacos , Polietilenoglicóis/química , Soroalbumina Bovina/administração & dosagem , Materiais Biocompatíveis , Células CACO-2 , Sequência de Carboidratos , Humanos , Oxirredução , Espectroscopia de Prótons por Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Clin Lab ; 63(11): 1801-1807, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29226637

RESUMO

BACKGROUND: The purpose of this study was to investigate the value of mean platelet volume (MPV) for prognosis of patients with acute cerebral infarction (ACI). METHODS: One hundred ACI patients and 80 healthy volunteers acting as healthy controls (HCs) were consecutively included in this study. Their baseline clinical and laboratory characteristics were extracted from an electroniccase system. ACI patients were followed for 90 days to collect the main study endpoints including poor prognosis, death due to cardiovascular causes, and the recurrence of stroke. ACI patients were evaluated after 7 days in the hospital using the National Institute of Health Stroke Scale (NIHSS) score to evaluate stroke severity on admission and using the modified Rankin Scale (mRS) to evaluate functional disorders. Receiver operating characteristic (ROC) curve analysis was used to estimate the predictive value of MPV on ACI. Kaplan-Meier survival analysis and Cox regression models were used to analyse the value of MPV as a predictor of ACI. RESULTS: This study suggested that MPV and rate of hypertension were higher in ACI patients than in the HC group. In the follow-up period, 32 ACI patients suffered study endpoints; they had higher average MPV, NIHSS scores, longer ACI onset times, and shorter event-free survival time compared to control patients. ROC curves showed that MPV was an index for prognosis of ACI patients with an AUC of MPV of 0.82 (95% confidence interval (CI): 0.74 - 0.90), and the best cutoff was 10.05 fL. MPV, NHISS scores, age, and TG were independent risk factors for endpoints of ACI patients. MPV with hazard ratio (HR) was 1.94 (95% CI, 1.37 - 2.72, p = 0.000), NIHSS score with HR was 1.22 (95% CI, 1.03 - 1.44, p = 0.021), age with HR was 1.06 (95% CI, 1.00 - 1.11, p = 0.038), and TG HR was 0.60 (95% CI, 0.36 - 1.00, p = 0.048) using Cox regression models. P  0.05 for all groups was considered statistically significant. CONCLUSIONS: Mean platelet volume was an independent risk factor and serves as a sensitive index for the prognosis of ACI patients.


Assuntos
Infarto Cerebral/sangue , Volume Plaquetário Médio , Idoso , Infarto Cerebral/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco
10.
Tumour Biol ; 36(3): 1567-72, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25359617

RESUMO

Vitamin D has important biological functions including modulation of the immune system and anti-cancer effects. There was no conclusive finding of the impact of serum vitamin D level on bladder cancer risk. A systemic review and meta-analysis was performed to assess the impact of serum 25-hydroxyvitamin D level on bladder cancer risk. The pooled relative risk (RR) with 95% confidence interval (95%CI) was used to assess the impact of serum 25-hydroxyvitamin D level on bladder cancer risk. A total of 89,610 participants and 2238 bladder cancer cases were finally included into the meta-analysis. There was no obvious heterogeneity among those included studies (I(2) = 0%). Meta-analysis total included studies which showed that a high serum 25-hydroxyvitamin D level could obviously decrease risk of bladder cancer (RR = 0.75, 95%CI 0.65-0.87, P < 0.001). In addition, the pooled RRs were not significantly changed by excluding any single study. The findings from the meta-analysis suggest an obvious protective effect of vitamin D against bladder cancer. Individuals with higher serum 25-hydroxyvitamin D levels suffer from less risk of subsequent bladder cancer.


Assuntos
Neoplasias da Bexiga Urinária/sangue , Vitamina D/análogos & derivados , Estudos de Casos e Controles , Estudos de Coortes , Suplementos Nutricionais , Humanos , Fatores de Risco , Vitamina D/sangue
11.
Chirality ; 26(2): 121-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24420919

RESUMO

A doubly stereocontrolled organocatalytic asymmetric Michael addition to the synthesis of substituted succinimides is described. Starting from aldehydes and maleimides, both enantiomers of the succinimides could be obtained in high to excellent yields (up to 98%) and enantioselectivities (up to 99%) when one of the two special chiral diterpene-derived bifunctional thioureas was individually used as a catalyst. Moreover, these catalysts can be efficiently used in large-scale catalytic synthesis with the same level of yield and enantioselectivity.


Assuntos
Diterpenos/química , Succinimidas/química , Tioureia/química , Catálise , Estrutura Molecular , Estereoisomerismo
12.
J Neurochem ; 124(3): 388-96, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23157378

RESUMO

Hyperhomocysteinemia (Hhcy) may induce memory deficits with ß-amyloid (Aß) accumulation and tau hyperphosphorylation. Simultaneous supplement of folate and vitamin B12 partially restored the plasma homocysteine level and attenuated tau hyperphosphorylation, Aß accumulation and memory impairments induced by Hhcy. However, folate and vitamin B12 treatment have no effects on Hhcy which has the methylenetetrahydrofolate reductase genotype mutation. In this study, we investigated the effects of simultaneous supplement of betaine on Alzheimer-like pathological changes and memory deficits in hyperhomocysteinemic rats after a 2-week induction by vena caudalis injection of homocysteine (Hcy). We found that supplementation of betaine could ameliorate the Hcy-induced memory deficits, enhance long-term potentiation (LTP) and increase dendritic branches numbers and the density of the dendritic spines, with up-regulation of NR1, NR2A, synaptotagmin, synaptophysin, and phosphorylated synapsin I protein levels. Supplementation of betaine also attenuated the Hcy-induced tau hyperphosphorylation at multiple AD-related sites through activation protein phosphatase-2A (PP2A) with decreased inhibitory demethylated PP2A(C) at Leu309 and phosphorylated PP2A(C) at Tyr307. In addition, supplementation of betaine also decreased Aß production with decreased presenilin-1 protein levels. Our data suggest that betaine could be a promising candidate for arresting Hcy-induced AD-like pathological changes and memory deficits.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Betaína/toxicidade , Homocisteína/toxicidade , Hiper-Homocisteinemia/tratamento farmacológico , Transtornos da Memória/tratamento farmacológico , Doença de Alzheimer/sangue , Animais , Modelos Animais de Doenças , Homocisteína/sangue , Hiper-Homocisteinemia/induzido quimicamente , Lipotrópicos/farmacologia , Masculino , Transtornos da Memória/induzido quimicamente , Ratos , Ratos Sprague-Dawley
13.
ScientificWorldJournal ; 2013: 468327, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23766691

RESUMO

The investigation on the structures, stabilities, and magnetism of Ni(m) Al(n) (m = 1-3, n = 1-9) clusters has been made by using first principles. We found some new ground-state structures which had not been found before. These mixed species prefer to adopt three-dimensional (3D) structures starting from four atoms. All the ground-state structures for the Ni-Al clusters are different from those of the corresponding pure Al clusters with the same number of atoms except for three atoms. The Mulliken population analysis shows that some charges transfer from the Al atoms to the Ni atoms. NiAl n (n = odd number) cations, Ni(2)Al(6) neutral, Ni(2)Al(1) and Ni(3)Al cations and anions, and Ni(3)Al(5) anion have the magnetic moments of 2 µ B. The magnetic moments of NiAl(4) and NiAl(6) cluster neutrals and cations are 2 µ B and 3 µ B, respectively. All the other cluster neutrals and ions do not have any nontrivial magnetic moments. The 3d electrons in Ni atoms are mainly responsible for the magnetism of the mixed Ni-Al clusters.


Assuntos
Alumínio/química , Campos Magnéticos , Modelos Químicos , Níquel/química , Teoria Quântica , Simulação por Computador
14.
Carbohydr Polym ; 294: 119777, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35868792

RESUMO

Aspidopterys obcordata vine is a Chinese Dai ethnic herb used to treat urolithiasis. However, the material basis and underlying mechanisms remain undefined. In this study, a 2.3 kD inulin-like A. obcordata fructan (AOFOS) was isolated by size exclusion column chromatography and characterized by ultrahigh-performance liquid chromatography-ion trap-time of flight mass spectrometry (UPLC-IT-TOF-MS), nuclear magnetic resonance (NMR) spectroscopy, gas chromatography mass spectrometry (GC-MS) and high-performance gel permeation chromatography (HGPC). In addition, AOFOS showed unique anti-urolithiasis activity in Drosophila kidney stone models. Mechanism study indicated that AOFOS reduced the size of calcium oxalate crystals by inhibiting the formation of large size crystals and the generation rate of calcium oxalate crystals as well as the crystal form conversion from calcium oxalate monohydrate (COM) to calcium oxalate dihydrate (COD).


Assuntos
Cálculos Renais , Malpighiaceae , Oxalato de Cálcio/química , Cristalização , Frutanos , Inulina , Cálculos Renais/química
15.
Chem Asian J ; 15(5): 560-563, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-31903670

RESUMO

An efficient preparation of sulfamate-fused 2-aminopyrroles was achieved through an isocyanide-based three-component [1+2+2] annulation of isocyanides, dialkyl acetylenedicarboxylates, and sulfamate-derived cyclic imines in good to excellent yields (up to 99 %). This reaction proceeds smoothly without any activation or modification of substances under neutral and metal-free conditions. The reaction could also be conveniently performed on a gram scale.

16.
Acta Pharmacol Sin ; 30(4): 485-93, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19305420

RESUMO

AIM: Localized delivery of growth factors has significant potential as a future therapeutic strategy in tissue engineering and regenerative medicine. A nanoparticle vehicle was created and evaluated in this study with the intent to deliver growth factors for periodontal regeneration. METHODS: Novel composite nanoparticles based on glycidyl methacrylate derivatized dextrans (Dex-GMA) and gelatin were fabricated by a facile method without using any organic solvents. The configurations of the resultant nanoparticles were evaluated by transmission electron microscopy, scanning electron microscopy, and atomic force microscope. Their surfaces were characterized by zeta-potential measurements, after which their properties including swelling, degradation, drug release, and cytotoxicity were also investigated using in vitro models. RESULTS: The particle size of Dex-GMA/gelatin nanoparticles (DG-NPs) ranged from 20 to 100 nm and showed a mono-disperse size distribution (mean diameter 53.7 nm) and a strongly negative surface zeta potential (-20 mV). The DG-NPs were characterized by good swelling and degradation properties in media including dextranase. The in vitro drug release studies showed that the efficient bone morphogenetic protein (BMP) release from DG-NPs was maintained for more than 12 d under degradation conditions, where more than 90% of the loaded BMP was released. No any relevant cell damage caused by DG-NPs was found in the cytotoxicity tests for a period of 24 h. CONCLUSION: These combined results demonstrate that DG-NPs fulfill the basic prerequisites for growth factor delivery. With further in vivo studies, those nanoparticles may offer a promising vehicle for the delivery of active drugs to the periodontium.


Assuntos
Proteínas Morfogenéticas Ósseas/administração & dosagem , Dextranos/administração & dosagem , Sistemas de Liberação de Medicamentos , Compostos de Epóxi/administração & dosagem , Gelatina/administração & dosagem , Metacrilatos/administração & dosagem , Nanopartículas/administração & dosagem , Adolescente , Proteínas Morfogenéticas Ósseas/química , Proteínas Morfogenéticas Ósseas/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Dextranos/química , Compostos de Epóxi/química , Gelatina/química , Humanos , Metacrilatos/química , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Periodonto/metabolismo , Regeneração
17.
Int J Pharm ; 307(1): 23-32, 2006 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-16260104

RESUMO

Recent developments of biotechnology have produced a great variety of protein and bioactive drugs. For these drugs to be used therapeutically, suitable drug delivery systems have become increasingly essential. Dextran-derived biomaterials have been considered to be compatible matrices for protein and bioactive drugs because of their hydrophilic properties and ability to control drug dissolution and permeability. A novel class of dextran-glycidylmethacrylate (Dex-GMA)/poly(ethylene glycol) (PEG) microspheres were designed and synthesized by polymerization of Dex-GMA emulsified in an aqueous PEG solution. Dex-GMA was prepared by substituting the hydroxyl groups in Dex by GMA. The drug loading and in vitro drug release was evaluated by routine procedure and the biological activity of BMP-loaded microspheres was studied by experimental cytology methods. Recombinant human bone morphogenetic protein-2 (rhBMP-2) were entrapped in dextran-derived microspheres quantitatively and with full preservation of their biological activity. In vitro release kinetics indicated that dextran-derived microspheres could retain rhBMP-2 in a variable manner depending on the preparation and degradation of the microspheres. The release profiles of rhBMP-2 from microspheres as a function of time showed that rhBMP-2 releasing kinetics in vitro fitted to first-order and Higuchi equations. The release profile in vitro was in accord with two phases kinetics law and more than 60% drug were released during 20 days. Cytology studies showed rhBMP-2 microspheres have good biological effects on cultured periodontal ligament cells, and could achieve a longer action time than concentration of rhBMP-2 solution. These properties make those microspheres interesting osteo-conductive BMP carriers, allowing to decrease the amount of implanted factor required for tissue regeneration.


Assuntos
Proteínas Morfogenéticas Ósseas/química , Dextranos/química , Portadores de Fármacos , Microesferas , Proteínas Recombinantes/química , Fator de Crescimento Transformador beta/química , Fosfatase Alcalina/metabolismo , Proteína Morfogenética Óssea 2 , Proteínas Morfogenéticas Ósseas/farmacologia , Regeneração Óssea , Células Cultivadas , Composição de Medicamentos , Compostos de Epóxi/química , Humanos , Metacrilatos/química , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteopontina , Ligamento Periodontal/efeitos dos fármacos , Ligamento Periodontal/metabolismo , Polietilenoglicóis/química , Proteínas Recombinantes/farmacologia , Sialoglicoproteínas/metabolismo , Fator de Crescimento Transformador beta/farmacologia
18.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 22(1): 76-8, 2005 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-15696487

RESUMO

OBJECTIVE: To identify the genetic defect causing autosomal dominant congenital cataract (ADCC) in a five-generation family in the northeast of China. METHODS: Linkage analysis was carried out with polymorphic microsatellites on the Human MapPairs marker set, special known loci. Mutation analysis of the candidate gene in the critical region was performed to detect the potential mutation. RESULTS: The maximum Lod score (2.44 at recombination fraction theta=0) was obtained for markers D1S498,D1S305, and D1S2844. The cataract locus in this family constellation was mapped to 1q21.1 and 21.44 cM interval between D1S2344 and D1S2844, which were known to flank the gene coding Connexin 50 (Cx50) or gap junction protein alpha-8 (GJA8). Sequencing of the coding region of GJA8 gene showed a heterozygous transversion T>G in exon 2, which resulted in the substitution of glycine for valine at amino acid 64, and this position was in the first connexin signature region that characterized this protein. CONCLUSION: This is the first report on a mutation in the first connexin signature region of the GJA8 and a different mutation within Cx50 revealed in this family, which might account for the phenotypic differences observed. Furthermore, this study confirmed that GJA8 plays a vital role in the maintenance of human lens transparency.


Assuntos
Catarata/genética , Conexinas/genética , Proteínas do Olho/genética , Mutação Puntual , Sequência de Bases , Catarata/congênito , China , Mapeamento Cromossômico , Cromossomos Humanos Par 1/genética , Análise Mutacional de DNA , Saúde da Família , Feminino , Heterozigoto , Humanos , Masculino , Repetições de Microssatélites/genética , Linhagem , Reação em Cadeia da Polimerase
19.
Neurobiol Aging ; 36(2): 867-76, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25457025

RESUMO

Participation in cognitively stimulating activities can preserve memory capacities in patients with Alzheimer's disease (AD), but the mechanism is not fully understood. Here, we used a rat model with hyperhomocysteinemia, an independent risk factor of AD, to study whether spatial training could remodel the synaptic and/or dendritic plasticity and the key molecular target(s) involved. We found that spatial training in water maze remarkably improved the subsequent short-term and long-term memory performance in contextual fear conditioning and Barnes maze. The trained rats showed an enhanced dendrite ramification, spine generation and plasticity in dentate gyrus (DG) neurons, and stimulation of long-term potentiation between perforant path and DG circuit. Spatial training also increased the levels of postsynaptic GluA1, GluN2A, GluN2B, and PSD93 with selective activation of calcium/calmodulin-dependent protein kinase II (CaMKII), although inhibition of CaMKII by stereotaxic injection of KN93 into hippocampal DG, abolished the training-induced cognitive improvement, dendrite ramification, and spine generation. We conclude that spatial training can preserve the cognitive function by CaMKII-dependent remodeling of dendritic plasticity in hyperhomocysteinemia-induced sporadic AD-like rats.


Assuntos
Doença de Alzheimer/fisiopatologia , Doença de Alzheimer/psicologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/fisiologia , Espinhas Dendríticas/fisiologia , Memória/fisiologia , Regeneração Nervosa/genética , Regeneração Nervosa/fisiologia , Plasticidade Neuronal/genética , Plasticidade Neuronal/fisiologia , Condicionamento Físico Animal/fisiologia , Navegação Espacial/fisiologia , Doença de Alzheimer/etiologia , Doença de Alzheimer/terapia , Animais , Cognição/fisiologia , Modelos Animais de Doenças , Potenciação de Longa Duração , Masculino , Terapia de Alvo Molecular , Ratos Sprague-Dawley
20.
Sci Rep ; 5: 9488, 2015 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-25820815

RESUMO

Alzheimer's disease (AD) is the most common neurodegenerative disorder and there is currently no efficient cure for this devastating disease. Cognitive stimulation can delay memory loss during aging and in patients with mild cognitive impairment. In 3 × Tg-AD mice, training decreased the neuropathologies with transient amelioration of memory decline. However, the neurobiological mechanisms underlying the learning-improved memory capacity are poorly understood. Here, we found in Tg2576 mice spatial training in Morris water maze (MWM) remarkably improved the subsequent associative memory acquisition detected by contextual fear conditioning. We also found that spatial training enhanced long term potentiation, dendrite ramification and spine generation in hippocampal dentate gyrus (DG) and CA1 neurons at 24 h after the training. In the molecular level, the MWM training remarkably activated calcium/calmodulin-dependent protein kinase II (CaMKII) with elevation of glutamate AMPA receptor GluA1 subunit (GluA1), postsynaptic density protein 93 (PSD93) and postsynaptic density protein 95 (PSD95) in the hippocampus. Finally, the training also significantly ameliorated AD-like tau and amyloid pathologies. We conclude that spatial training in MWM preserves associative memory capacity in Tg2576 mice, and the mechanisms involve augmentation of dendrite ramification and spine generation in hippocampus.


Assuntos
Dendritos/metabolismo , Memória , Aprendizagem Espacial , Doença de Alzheimer , Peptídeos beta-Amiloides/metabolismo , Animais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Giro Denteado/metabolismo , Modelos Animais de Doenças , Proteína 4 Homóloga a Disks-Large , Guanilato Quinases/metabolismo , Hipocampo/metabolismo , Humanos , Potenciação de Longa Duração , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Plasticidade Neuronal , Fosforilação , Células Piramidais/metabolismo , Receptores de AMPA/metabolismo , Proteínas tau/metabolismo
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