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1.
J Integr Neurosci ; 21(5): 147, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36137973

RESUMO

OBJECTIVE: This study aimed to conduct proteomic analysis of the sphincter in a neurogenic bladder caused by T10 spinal cord injury. The differentially expressed proteins (DEPs) of the sphincters (internal urethral sphincter) in the neurogenic bladders (NBs) of rats after complete transection of the T10 spinal cord segment were screened using tandem mass tag (TMT)-based quantitative labeling, and their biological information was analyzed. METHODS: Twelve adult Sprague Dawley rats out of 40 were randomly assigned to the blank group (n = 12), while the remaining 28 were placed in the T10 spinal cord injury model via modified Hassan Shaker spinal cord transection; 12 of these rats were then randomly selected as the model group. The rats in both groups underwent urodynamics detection and hematoxylin and eosin (H&E) staining. The proteins expressed in the bladder sphincter were detected using TMT-based quantitative proteomics. DEPs were defined as proteins with fold change >1.5 or <1/1.5, p < 0.05, and unique peptide ≥2. The DEPs were subjected to Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis using KOBAS 3.0., and gene ontology functional annotation analysis was performed using the Cytoscape 3.7.1. BiNGO plug-in. The protein-protein interaction network was then constructed using the interactive gene-retrieval tool STRING and Cytoscape software. RESULTS: The leak-point pressure and maximum cystometric volume in the model group were significantly higher than those in the blank group (p < 0.01), and H&E staining showed continuous interruption of the bladder sphincter fibers in the model group. A total of 250 DEPs were screened in the bladder sphincter, 83 of which were up-regulated and 167 of which were down-regulated. KEGG analysis of the DEPs was used to screen 15 pathways, including metabolic pathways, extracellular matrix (ECM)-receptor interaction, adhesion spots, the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway, the cytochalasin signaling pathway, and the advanced glycation end-products (AGE)/receptor for AGEs (RAGE) signaling pathway in diabetic complications and vascular smooth muscle contraction. CONCLUSIONS: It is of great significance to explore the pathological mechanism of non-inhibitory contraction of the bladder sphincter caused by spinal cord injury above the T10 segment from the perspective of ECM-receptor interaction, focal adhesion-activated PI3K/Akt signaling pathway, and cell relaxation signaling pathways. Synaptic vesicle glycoprotein (Sv2A) involved in the release of neurotransmitters from synaptic vesicles, arrestin ß2 inhibitory proteins involved in α-adrenergic receptors and G-protein-coupled receptor internalization, and calmodulin and calmodulin binding protein involved in calcium-sensitive signaling pathways may be potential targets for developing new ways to treat bladder sphincter overactivity caused by T10 spinal cord injury.


Assuntos
Traumatismos da Medula Espinal , Bexiga Urinaria Neurogênica , Animais , Arrestinas , Cálcio , Calmodulina , Proteínas de Ligação a Calmodulina , Citocalasinas , Amarelo de Eosina-(YS) , Hematoxilina , Fosfatidilinositol 3-Quinase , Fosfatidilinositol 3-Quinases , Proteômica , Proteínas Proto-Oncogênicas c-akt , Ratos , Ratos Sprague-Dawley , Receptores Adrenérgicos alfa , Receptores Acoplados a Proteínas G , Medula Espinal , Traumatismos da Medula Espinal/complicações , Bexiga Urinaria Neurogênica/etiologia , Bexiga Urinaria Neurogênica/terapia
2.
Front Plant Sci ; 13: 942366, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35982707

RESUMO

The Wanfunao site was a large Chu settlement in Zhou Dynasty. It was located on an alluvial plain along the Yangtze River in the Yichang section. The region around the site comprised mountains, hills, and plains, which was a compatible environment for the cultivation of various crops. Previous studies have suggested that the middle and lower reaches of the Yangtze River are one of the most productive regions for rice cultivation. Besides rice, however, seven dryland crops have been found at the Wanfunao site: foxtail millet, broomcorn millet, wheat, barley, oat, buckwheat, and adzuki bean. Among them, foxtail millet and rice are most ubiquitous. The crop assemblage has revealed that the northern dryland crops, including those were newly adapted cereals such as foxtail millet, wheat, and barley, gradually dispersed southward and became a part of the diet along with rice. This can be attributed to southern Chinese inhabitants' reclamation of the hilly environment for agriculture. Although communities in southern China had cultivated rice on the plains for thousands of years, newly introduced dryland crops from north China adapted to mountainous environments better. The development of multi-cropping systems in southern China likely involved changes in agricultural ontology associated with the adaptation of northern crops in southern environments newly encountered. Additionally, the assemblage of foxtail millet grain/rice spikelet base in the site may have been used for livestock feeding. A wide range of landforms, compatible farming, and surplus agricultural products for husbandry may have been a part of the economic foundation that facilitated the rise of Chu.

3.
BMC Neurol ; 22(1): 160, 2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35490209

RESUMO

BACKGROUND: Operating an aircraft is associated with a large mental workload; however, knowledge of the mental workload of ROV operators is limited. The purpose of this study was to establish a digital system for assessing the mental workload of remotely operated vehicle (ROV) operators using hemodynamic parameters, and compare results of different groups with different experience levels. METHOD: Forty-one trainee pilots performed flight tasks once daily for 5 consecutive days in a flight simulation. Forty-five pilots experienced pilots and 68 experienced drivers were also included. Hemodynamic responses were measured by functional near-infrared spectroscopy (fNIRS). RESULTS: The median duration of peak oxyhemoglobin was 147.13 s (interquartile range [IQR] 21.97, 401.70 s) in the left brain and 180.74 s (IQR 34.37, 432.01 s) in the right brain in the experienced pilot group, and 184.42 s (IQR 3.41, 451.81 s) on day 5 in the left brain and 160.30 s (IQR 2.62, 528.20 s) in the right brain in the trainee group. CONCLUSION: Navigation training reduces peak oxyhemoglobin duration, and may potentially be used as a surrogate marker for mental workload of ROV operators. Peak oxyhemoglobin concentration during s task may allow development of a simplified scheme for optimizing flight performance based on the mental workload of a pilot.


Assuntos
Pilotos , Aeronaves , Humanos , Oxiemoglobinas , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Carga de Trabalho
4.
Biomaterials ; 236: 119803, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32028170

RESUMO

Nanobubbles, as a kind of new ultrasound contrast agent (UCAs), have shown promise to penetrate tumor vasculature to allow for targeted imaging. However, their inherent physical instability is an ongoing concern that could weaken their imaging ability with ultrasound. Gas vesicles (GVs), which are genetically encoded, naturally stable nanostructures, have been developed as the first ultrasonic biomolecular reporters which showed strong contrast enhancement. However, further development of tumor imaging with GVs is limited by the quick clearance of GVs by the reticuloendothelial system (RES). Here, we developed PEGylated HA-GVs (PH-GVs) for in-tumor molecular ultrasound imaging by integrating polyethylene glycol (PEG) and hyaluronic acid (HA) in GV shells. PH-GVs were observed to accumulate around CD44-positive cells (SCC7) but not be internalized by macrophage cell line RAW 264.7. Green fluorescence from PH-GVs was found around cell nuclei in the tumor site after 6 h and the signal was sustained over 48 h following tail injection, demonstrating PH-GVs' ability to escape the clearance from the RES and to penetrate tumor vasculature through enhanced permeability and retention (EPR) effects. Further, PH-GVs produced strong ultrasound contrast in the tumor site in vivo, with no obvious side-effects detected following intravenous injection. Thus, we demonstrate the potential of PH-GVs as novel, nanosized and targeted UCAs for efficient and specific molecular tumor imaging, paving the way for the application of GVs in precise and personalized medicine.


Assuntos
Nanoestruturas , Neoplasias , Linhagem Celular Tumoral , Meios de Contraste , Humanos , Imagem Molecular , Neoplasias/diagnóstico por imagem , Ultrassonografia
5.
J Psychosom Res ; 130: 109913, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31918359

RESUMO

OBJECTIVE: The aim of this systematic review is to synthesize relevant evidence and illustrate the relationship between sleep and cognitive function in patients with heart failure. METHODS: A literature search was conducted on Embase, PubMed, Web of Science, CINAHL, PsychINFO, Cochrane Library, China National Knowledge Infrastructure (CNKI) and Wan Fang to identify relevant studies. RESULTS: Seven studies, which enrolled a total of 1218 heart failure patients, were included in this review. These articles investigating the relationship between sleep and cognitive performance in patients with heart failure had inconsistent results. Five studies confirmed that sleep quality and insomnia were significantly associated with cognitive function, including global cognition, attention, and executive function, whereas the other two studies indicated no statistically significant relationship between sleep and cognitive function. CONCLUSION: Although limited evidence restricts the overall conclusions, this review might provide new opportunities to identify patients with heart failure that are at high risk for cognitive decline. Further studies across a longer period are needed to confirm the relationship between sleep and cognitive function in patients with heart failure.


Assuntos
Cognição/fisiologia , Insuficiência Cardíaca/fisiopatologia , Sono/fisiologia , Função Executiva , Insuficiência Cardíaca/complicações , Humanos , Distúrbios do Início e da Manutenção do Sono/complicações
6.
Clin Exp Hypertens ; 42(4): 315-321, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-31394956

RESUMO

Background: Prehypertension is common in China, but its causes and associated factors have not been well studied. This study aimed to examine the age and gender-specific associations between CVD risk factor clustering and prehypertension among adults in China.Methods: This cross-sectional study used data from participants (n = 8735) aged over 45 in the China Health and Retirement Longitudinal Study (CHARLS) Baseline conducted from 2011-2012. The participants' data were collected using standard questionnaires, anthropometric, and biochemical tests. Logistic regression analyses were used to examine the associations between cardiovascular risk factors, their clustering and prehypertension.Results: Overall, 21.1%, 39.5%, 27.6% and 11.8% participants had 0, 1, 2, ≥ 3 CVD risk factors in prehypertension group, respectively. Diabetes and overweight/obesity were significantly associated with prehypertension (OR, 1.24; 95% confidence interval [CI], 1.06-1.44; OR, 1.55; 95% CI, 1.38-1.75) in the overall population, and diabetes was associated with prehypertension only in men (OR, 1.26; 95% CI, 1.00-1.58) and older adults (OR, 1.32; 95% CI, 1.03-1.69). Moreover, participants with 1, 2 and ≥3 risk factors had increased odds of having prehypertension (OR, 1.29; 95% CI, 1.12-1.49; OR, 1.59; 95% CI, 1.31-1.78; OR, 2.05; 95% CI, 1.66-2.53, respectively) and existed dose-response relationship, regardless of age and gender.Conclusions: This study indicated that CVD risk factor clustering was significantly associated with prehypertension and hypertension. These results provide valuable information for health professionals to better understand the impact of CVD risk factor clustering on prehypertension and hypertension.


Assuntos
Doenças Cardiovasculares , Pré-Hipertensão , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , China/epidemiologia , Análise por Conglomerados , Estudos Transversais , Diabetes Mellitus/epidemiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Pré-Hipertensão/diagnóstico , Pré-Hipertensão/epidemiologia , Pré-Hipertensão/fisiopatologia , Prevalência , Fatores de Risco , Inquéritos e Questionários
7.
J Clin Nurs ; 29(3-4): 320-329, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31698508

RESUMO

AIMS AND OBJECTIVES: To summarise the current evidence on comorbid type 2 diabetes mellitus (T2DM) related to 30-day readmission and hospital length of stay (LOS) among patients with acute coronary syndrome (ACS) and evidence on the effectiveness of self-management programmes for patients with both conditions. BACKGROUND: Acute coronary syndrome and T2DM remain two major diseases leading to serious consequences. Thirty-day readmission and LOS were considered indicators of the quality of care, with the understanding that the potential significant effects of these outcomes could be varied. DESIGN: This scoping review followed the methodology described by Arksey and O'Malley. METHODS: Five databases including PubMed, Embase, Cochrane Library, Web of Science and CINAHL were searched, and a total of 20 articles involving 913,807 patients were included. Results were reported in accordance with PRISMA-ScR guidelines. RESULTS: The results indicated that patients with both ACS and T2DM have prolonged LOS and increased 30-day readmission rates. The findings supported that improvements in patient self-management behaviour for optimal health outcomes were partially successful by effective self-management programmes; however, few articles on intervention programmes specifically designed for patients with two conditions were found. CONCLUSION: Prolonged LOS and increased 30-day readmission rates are found among patients with ACS and T2DM. Based on few pilot studies building on each other, the effectiveness of self-management programmes in promoting self-care behaviour, self-efficacy and knowledge for patients with ACS and T2DM cannot be concluded. RELEVANCE TO CLINICAL PRACTICE: Findings from this review provide valuable information on and a better understanding of readmissions and LOS among patients with ACS and T2DM for healthcare providers. Future developments and implementations of effective self-management programmes should target patients with dual diagnoses to improve health behaviour and reduce readmission and LOS.


Assuntos
Síndrome Coronariana Aguda/complicações , Diabetes Mellitus Tipo 2/complicações , Tempo de Internação/estatística & dados numéricos , Readmissão do Paciente/estatística & dados numéricos , Síndrome Coronariana Aguda/psicologia , Comorbidade , Diabetes Mellitus Tipo 2/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Autogestão/educação , Autogestão/psicologia
8.
Neurosci Bull ; 35(5): 826-840, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31062334

RESUMO

Motor timing is an important part of sensorimotor control. Previous studies have shown that beta oscillations embody the process of temporal perception in explicit timing tasks. In contrast, studies focusing on beta oscillations in implicit timing tasks are lacking. In this study, we set up an implicit motor timing task and found a modulation pattern of beta oscillations with temporal perception during movement preparation. We trained two macaques in a repetitive visually-guided reach-to-grasp task with different holding intervals. Spikes and local field potentials were recorded from microelectrode arrays in the primary motor cortex, primary somatosensory cortex, and posterior parietal cortex. We analyzed the association between beta oscillations and temporal interval in fixed-duration experiments (500 ms as the Short Group and 1500 ms as the Long Group) and random-duration experiments (500 ms to 1500 ms). The results showed that the peak beta frequencies in both experiments ranged from 15 Hz to 25 Hz. The beta power was higher during the hold period than the movement (reach and grasp) period. Further, in the fixed-duration experiments, the mean power as well as the maximum rate of change of beta power in the first 300 ms were higher in the Short Group than in the Long Group when aligned with the Center Hit event. In contrast, in the random-duration experiments, the corresponding values showed no statistical differences among groups. The peak latency of beta power was shorter in the Short Group than in the Long Group in the fixed-duration experiments, while no consistent modulation pattern was found in the random-duration experiments. These results indicate that beta oscillations can modulate with temporal interval in their power mode. The synchronization period of beta power could reflect the cognitive set maintaining working memory of the temporal structure and attention.


Assuntos
Antecipação Psicológica/fisiologia , Ritmo beta/fisiologia , Força da Mão/fisiologia , Desempenho Psicomotor/fisiologia , Córtex Sensório-Motor/fisiologia , Animais , Feminino , Macaca mulatta , Masculino , Movimento/fisiologia , Estimulação Luminosa/métodos
9.
ACS Synth Biol ; 8(2): 332-345, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30632732

RESUMO

Secondary messengers (such as (p)ppGpp and c-di-GMP) were proved to play important roles in antibiotic biosynthesis in actinobacteria. In this study, we found that transcription levels of erythromycin-biosynthetic ( ery) genes were upregulated in nutrient limitation, which depended on (p)ppGpp in Saccharopolyspora erythraea. Further study demonstrated that the expression of ery genes and intracellular concentrations of (p)ppGpp showed synchronization during culture process. The erythromycin yield was significantly improved (about 200%) by increasing intracellular concentration of (p)ppGpp through introduction of C-terminally truncated (p)ppGpp synthetase RelA (1.43 kb of the N-terminal segment) from Streptomyces coelicolor into S. erythraea strain NRRL2338 (named as WT/pIB-P BAD- relA1-489). As the intracellular concentration of (p)ppGpp in an industrial erythromycin-high-producing strain E3 was greatly higher (about 10- to 100-fold) than WT strain, the applications of the above-described strategy did not work in E3 strain. Further research revealed that low concentration of 2-oxoglutarate in E3 strain exerted a "nitrogen-rich" pseudosignal, leading to the downregulation of nitrogen metabolism genes, which limited the use of nitrogen sources and thus the high intracellular (p)ppGpp concentration. Furthermore, the secondary messenger, c-di-GMP, was proved to be able to activate ery genes transcription by enhancing binding of BldD to promoters of ery genes. Overexpressing the diguanylate cyclase CdgB from S. coelicolor in S. erythraea increased the intracellular c-di-GMP concentration, and improved erythromycin production. These findings demonstrated that increasing the concentration of intracellular secondary messengers can activate ery genes transcription, and provided new strategies for designing metabolic engineering based on secondary messengers to improve antibiotics yield in actinobacteria.


Assuntos
GMP Cíclico/análogos & derivados , Eritromicina/metabolismo , Engenharia Metabólica/métodos , Saccharopolyspora/metabolismo , GMP Cíclico/metabolismo , Regulação Bacteriana da Expressão Gênica , Regiões Promotoras Genéticas/genética
10.
J Musculoskelet Neuronal Interact ; 18(3): 389-392, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30179217

RESUMO

We reported a Stiff person syndrome (SPS) patient with elevated autoantibodies against cardiolipin and ß2 glycoprotein 1 but without glutamic acid decarboxylase (GAD) antibodies. A 40-year male was admitted due to limited mouth opening for 1 week. His blood routine, biochemical, infectious diseases, tumor markers, radiographic examinations were all normal. At day 3 (D3) after admission, he developed paroxysmal systemic muscle rigidity. At D6, the on-duty physician occasionally gave oral clonazepam, which effectively relieved the symptom. At D13, the titers of cardiolipin and ß2 glycoprotein 1 autoantibodies elevated but the remaining autoantibodies were all in normal ranges. After clonazepam treatment for 1 week, the symptoms were basically relieved, and the titers of these two antibodies returned to normal range with the relief of symptoms. During the 3 years of follow-up, the symptoms did not present again, and the titers of both antibodies were stable in the normal ranges. He had no tumor and other immune system diseases. In summary, we reported a SPS case with elevated cardiolipin and ß2 glycoprotein 1 autoantibodies. The patient was highly responsive to clonazepam therapy, and had favorable outcome in the 3 years follow-up. Our report is helpful for better understand the heterogeneous feature of SPS.


Assuntos
Autoanticorpos , Cardiolipinas/imunologia , Rigidez Muscular Espasmódica/imunologia , beta 2-Glicoproteína I/imunologia , Adulto , Humanos , Masculino
11.
Can J Neurol Sci ; 41(4): 486-92, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24878474

RESUMO

OBJECTIVE: This study aimed to describe the frequency and temporal profile of acute cerebral infarction (ACI) using a continuous glucose monitoring system (CGMS) in patients with and without type 2 diabetes mellitus (T2DM) and explore the impact of blood glucose fluctuations on the short-term prognosis of ACI. METHODS: The subjects were divided into four groups: T2DM with acute cerebral infarction (DMCI, Group A, n=56); T2DM without acute cerebral infarction (DM-NCI, Group B, n=36); Acute cerebral infarction patients without T2DM (NDM-CI, Group C, n=54); Healthy control group (NG, Group D, n=36). The National Institutes of Health Stoke Scale (NIHSS) and modified Rankin scale (mRs) were collected in Group A and C. All subjects were monitored for 72 hours using the CGMS. Indices such as fasting blood glucose (FBG) and mean amplitude of glycemic excursions (MAGE) were calculated. Glycemic excursions were compared between Group A, B, C and Group D, respectively. Multiple linear regression analysis and logistic analysis was applied. RESULTS: MAGE is related to NIHSS, homocysteine (HCY), HOMA-IR, FBG, CRP and IMT, while NIHSS is related to CRP, HCY, HOMA-IR, IMT. The factors impacting the short-term prognosis of ACI were NIHSS, HBA1C and MAGE. CONCLUSION: Larger glucose fluctuations are associated with more stroke risk factors and are associated with a poorer short-term prognosis. More attention should be paid to glucose fluctuations in patients with ACI and a history of T2DM.


Assuntos
Glicemia/metabolismo , Infarto Cerebral/sangue , Infarto Cerebral/diagnóstico , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Doença Aguda , Idoso , Automonitorização da Glicemia/tendências , Infarto Cerebral/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
J Chromatogr A ; 1246: 117-22, 2012 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-22503616

RESUMO

Monofunctional maleimide polyethylene glycol (mono-mal-PEG) with average molecular weight up to 40 kDa can be used as a raw material for the PEGylation of therapeutic proteins. A possible impurity in this raw material which needs to be controlled is the bisfunctional maleimide-PEG, which has a similar average molecular weight to mono-mal-PEG. Chromatographic separation and detection of low level bis-mal-PEG in mono-mal-PEG presents a major challenge because of the polydispersity of the analytes and the minor difference between the desired mono-mal-PEG and the bis-mal-PEG impurity. In this study, linear mal-PEGs were first derivatized with a specially designed cys-peptide containing a UV chromophore and multiple ionizable sites. Separations were then carried out by reversed-phase HPLC with UV detection at 360 nm. Mono-mal-PEG and bis-mal-PEG were well resolved using a Gemini C18 column with an aqueous-acetonitrile mobile phase. Retention times increased as PEG molecular weight increased from 10 kDa to 40 kDa, while selectivities decreased as PEG molecular weight increased. Results from systematically designed studies for optimization of critical parameters including gradient slope, column temperature, and acidic modifier in the mobile phase led to the selection of the final separation conditions. The developed method conditions were specific, accurate, and sensitive for detecting bis-mal-PEG as an impurity in mono-mal-PEG with limit of quantitation of 0.2% and may be used to assess the quality of mono-mal-PEG as a raw material for protein PEGylation.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Maleimidas/isolamento & purificação , Polietilenoglicóis/isolamento & purificação , Sistemas de Liberação de Medicamentos , Maleimidas/química , Peso Molecular , Polietilenoglicóis/química , Reprodutibilidade dos Testes
14.
J Pharm Biomed Anal ; 53(3): 309-14, 2010 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-20439146

RESUMO

5-Chlorovaleroyl chloride (5-CVC) is commonly used as an alkylating agent in the synthesis of pharmaceutical intermediates, active ingredients, as well as other specialty chemicals. It is critical to monitor the impurities present in 5-CVC as they may have a direct impact on the impurity profile and quality of the final product. This paper describes the development and validation of a GC-FID method for the analysis of low level impurities of 5-CVC. This is the first method reported in the literature for the impurity determination of 5-CVC. The results of GC method development, with and without sample derivatization, are presented. The final method uses methanol for derivatization and separates methyl esters of 5-CVC and the key impurities, 4-pentenoyl chloride, 4-chlorovaleroyl chloride, 5-chlorohexanoyl chloride, and 4-methyl-5-chlorovaleroyl chloride. 3-Methoxypyridine was used in the sample solvent to enable the detection of 5-chlorovaleric acid (5-CVA) which is the major degradant of 5-CVC. The method was validated for specificity, linearity, accuracy, precision, sensitivity, and robustness. This simple and robust GC approach may be applicable to impurity analysis of other acid chlorides or acid halides.


Assuntos
Cromatografia Gasosa/métodos , Contaminação de Medicamentos , Valeratos/análise , Calibragem , Estabilidade de Medicamentos , Sensibilidade e Especificidade , Valeratos/química
15.
Cancer Res ; 64(19): 7099-109, 2004 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-15466206

RESUMO

The RAS/RAF signaling pathway is an important mediator of tumor cell proliferation and angiogenesis. The novel bi-aryl urea BAY 43-9006 is a potent inhibitor of Raf-1, a member of the RAF/MEK/ERK signaling pathway. Additional characterization showed that BAY 43-9006 suppresses both wild-type and V599E mutant BRAF activity in vitro. In addition, BAY 43-9006 demonstrated significant activity against several receptor tyrosine kinases involved in neovascularization and tumor progression, including vascular endothelial growth factor receptor (VEGFR)-2, VEGFR-3, platelet-derived growth factor receptor beta, Flt-3, and c-KIT. In cellular mechanistic assays, BAY 43-9006 demonstrated inhibition of the mitogen-activated protein kinase pathway in colon, pancreatic, and breast tumor cell lines expressing mutant KRAS or wild-type or mutant BRAF, whereas non-small-cell lung cancer cell lines expressing mutant KRAS were insensitive to inhibition of the mitogen-activated protein kinase pathway by BAY 43-9006. Potent inhibition of VEGFR-2, platelet-derived growth factor receptor beta, and VEGFR-3 cellular receptor autophosphorylation was also observed for BAY 43-9006. Once daily oral dosing of BAY 43-9006 demonstrated broad-spectrum antitumor activity in colon, breast, and non-small-cell lung cancer xenograft models. Immunohistochemistry demonstrated a close association between inhibition of tumor growth and inhibition of the extracellular signal-regulated kinases (ERKs) 1/2 phosphorylation in two of three xenograft models examined, consistent with inhibition of the RAF/MEK/ERK pathway in some but not all models. Additional analyses of microvessel density and microvessel area in the same tumor sections using antimurine CD31 antibodies demonstrated significant inhibition of neovascularization in all three of the xenograft models. These data demonstrate that BAY 43-9006 is a novel dual action RAF kinase and VEGFR inhibitor that targets tumor cell proliferation and tumor angiogenesis.


Assuntos
Benzenossulfonatos/farmacologia , MAP Quinase Quinase Quinase 1 , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Piridinas/farmacologia , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Administração Oral , Animais , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Humanos , MAP Quinase Quinase Quinases/antagonistas & inibidores , MAP Quinase Quinase Quinases/metabolismo , Camundongos , Camundongos Nus , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neoplasias/irrigação sanguínea , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/enzimologia , Niacinamida/análogos & derivados , Compostos de Fenilureia , Proteínas Proto-Oncogênicas c-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-raf/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Sorafenibe , Ensaios Antitumorais Modelo de Xenoenxerto
16.
J Chromatogr A ; 953(1-2): 67-77, 2002 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-12058948

RESUMO

The selectivity and retention properties of a zirconia stationary phase were reversibly altered using various ligands containing Lewis base functional groups. A simple loading procedure allowed a variety of ligands to be attached to the zirconia surface via Lewis interactions. The resulting stationary phases were shown to be stable and produced different selectivity and retention properties from the native zirconia material. The metal oxide adsorbent was converted to a diol-type stationary phase using glucose-6-phosphate for use under normal-phase conditions. Reversed-phase supports were produced by loading either octyl- or octadecylphosphonic acid onto the native zirconia support. The properties of these new phases were then compared to commercially available bonded silica analogs. Ligands bound to the surface in this manner were effectively removed and the native zirconia was regenerated using a dilute base wash procedure.


Assuntos
Cromatografia Líquida de Alta Pressão/instrumentação , Zircônio/química , Glucose-6-Fosfato/química , Organofosfonatos/química
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