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1.
BMC Med Imaging ; 23(1): 98, 2023 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-37507673

RESUMO

BACKGROUND: Sinonasal rhabdomyosarcoma (RMS) in adults is extremely rare, and early diagnosis and treatment are crucial to improve the patient's prognosis. The purpose of this study was to evaluate the magnetic resonance imaging (MRI) findings of sinonasal RMS in adults and analyze the correlations between the imaging features and pathological subtypes. METHODS: We reviewed 27 patients with pathologically proven RMS of the nasal cavity and paranasal sinuses, including embryonal RMS (ERMS) in 14 patients, alveolar RMS (ARMS) in seven patients, and mixed-type RMS in six patients. Conventional MRI was performed in all 27 patients, and high-resolution diffusion-weighted imaging was conducted in 25 patients. The tumor location, size, morphological features, signal intensity, texture, contrast enhancement characteristics, lymph node metastases, apparent diffusion coefficients (ADCs), and involvement of local soft tissues were independently assessed by two authors. RESULTS: On MR imaging, sinonasal RMS appeared isointense on T1-weighted imaging in 21 cases (77.8%) and heterogeneously hyperintense on T2-weighted imaging in 18 patients (66.7%). After enhancement, the tumors were heterogeneously enhanced in 24 cases (88.9%). Botryoid enhancement with multiple small rings resembling bunches of grapes was found in 15 cases (55.6%). Mucosal invasion of the maxillary sinus was identified in 51.9% patients. Skull and orbit involvement were found in 55.6% and 81.5% patients, respectively. Lymph node metastasis was seen in 18 cases (66.7%). There were significant differences in botryoid enhancement (P = 0.044) and skull involvement (P = 0.044) among different histological subtypes. The mean ADC value of RMS was 0.73 ± 0.082 × 10-3 mm2/s, and there was no significant difference among different histological subtypes. CONCLUSIONS: Some characteristic MRI findings such as botryoid enhancement in the ethmoid sinus, involvement of the orbit and skull, and a lower ADC value can provide important clues for preoperative diagnosis of sinonasal RMS in adults. Further, botryoid enhancement was more common in ERMS, while skull involvement was more common in ARMS.


Assuntos
Seios Paranasais , Rabdomiossarcoma , Adulto , Humanos , Imageamento por Ressonância Magnética , Imagem de Difusão por Ressonância Magnética , Seios Paranasais/diagnóstico por imagem , Rabdomiossarcoma/diagnóstico por imagem , Rabdomiossarcoma/patologia , Estudos Retrospectivos , Espectroscopia de Ressonância Magnética
2.
Phys Chem Chem Phys ; 25(28): 19082-19090, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37427572

RESUMO

By using density functional theory calculations combined with the nonequilibrium Green's function method and machine learning, we systematically studied the thermoelectric properties of four kinds of porous graphene nanosheets (PGNS) before and after nitrogen doping. The results show that the thermoelectric performance of porous graphene nanosheets along the armchair or zigzag chiral direction is improved due to the dramatically enhanced power factor caused by nitrogen doping. The calculated ZT values of nitrogen-doped porous graphene nanosheets are boosted by about one order of magnitude compared with those of undoped porous graphene nanosheets at room temperature. More importantly, an anisotropic thermoelectric transport is found in the nitrogen-doped porous graphene nanosheets. The results show that the ZT values of nitrogen-doped porous graphene nanosheets along the zigzag transport direction are nearly 11 times larger than those of them along the armchair transport direction. These results reveal that the thermoelectric properties of porous graphene nanosheets can be well regulated by nitrogen doping, and provide a good theoretical guidance for their application in thermoelectric devices.

3.
BMC Psychiatry ; 23(1): 516, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37464335

RESUMO

BACKGROUND: work alienation is receiving increasing attention as a psychological risk at work, and little is known about the mechanisms of role ambiguity and work alienation in nurses in the context of the COVID-19 pandemic. This article aims to examine how role ambiguity affects work alienation among Chinese nurses during the two years after COVID-19 pandemic and verify emotional exhaustion as mediators. METHODS: A cross-sectional study design was used to recruit 281 Chinese nurses. Nurses completed online questionnaires containing demographic characteristics, role ambiguity, emotional exhaustion, and work alienation, and SPSS 26.0 and AMOS 24.0 were used for data analysis and structural equation modelling. RESULTS: work alienation scores were (34.64 ± 10.09), work alienation was correlated with role ambiguity and emotional exhaustion (r1 = 0.521, r2 = 0.755; p < .01), and role ambiguity was positively correlated with emotional exhaustion (r = 0.512; p < .01). A mediating effect of emotional exhaustion between role ambiguity and work alienation held (mediating effect of 0.288, 95% CI: 0.221-0.369, accounting for 74.8% of the total effect). CONCLUSION: Role ambiguity has a significant direct effect on nurses' feelings of alienation and exacerbates alienation through emotional exhaustion. Clarifying roles at work and being less emotionally drained are effective ways to reduce nurses' feelings of alienation.


Assuntos
Esgotamento Profissional , COVID-19 , Enfermeiras e Enfermeiros , Recursos Humanos de Enfermagem Hospitalar , Humanos , Estudos Transversais , População do Leste Asiático , Pandemias , Esgotamento Profissional/psicologia , Recursos Humanos de Enfermagem Hospitalar/psicologia , Emoções , Inquéritos e Questionários
4.
Curr Med Imaging ; 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37018523

RESUMO

BACKGROUND: Chondrosarcoma in the mastoid is extremely rare, and it is easily misdiagnosed as a facial nerve schwannoma. OBJECTIVE: To identify and compare computed tomography (CT) and magnetic resonance imaging (MRI) features of chondrosarcoma in the mastoid involving the facial nerve, including diffusion-weighted MRI characteristics, with those of facial nerve schwannoma. METHOD: CT and MRI features of 11 chondrosarcomas in the mastoid involving the facial nerve and 15 facial nerve schwannomas, confirmed by histopathology, were retrospectively reviewed. The tumor location, size, morphological features, bone change, calcification, signal intensity, texture, enhancement characteristics, the extent of lesions, and apparent diffusion coefficients (ADCs) were evaluated. RESULTS: On CT imaging, calcification could be found in 81.8% of chondrosarcomas (9/11) and 33.3% of facial nerve schwannomas (5/15). Chondrosarcoma in the mastoid appeared significantly hyperintense on T2-weighted images (T2WI) with low signal intensity septa in eight patients (72.7%, 8/11). After contrast, all chondrosarcomas showed inhomogeneous enhancement, and septal and peripheral enhancement could be found in six cases (54.5%, 6/11). Facial nerve schwannoma demonstrated inhomogeneous hyperintensity on T2WI in 12 cases (80%, 12/15), with obvious hyperintense cystic changes in seven cases. There were significant differences in calcification (P=0.014), T2 signal intensity (P=0.006), and septal and peripheral enhancement (P=0.001) between chondrosarcomas and facial nerve schwannomas. The ADCs of chondrosarcoma were significantly higher than those of facial nerve schwannomas (P<0.001). CONCLUSION: CT and MRI with ADCs had the potential to improve the diagnostic accuracy of chondrosarcoma in the mastoid involving the facial nerve.

5.
Curr Med Imaging ; 19(11): 1315-1323, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36650647

RESUMO

BACKGROUND: Teratoma is a true neoplasm composed of a number of different types of tissue derived from the three germinal layers but rarely occurs in the middle ear (ME). The features of middle ear teratomas (MET) have not been well described. OBJECTIVE: The objective of this study is to explore the clinical and imaging features of MET, and report 2 rare cases of MET with ear malformation that have never been reported. MATERIALS AND METHODS: The clinical, CT and MRI data of 8 patients with a pathological diagnosis of MET were collected and retrospectively mined, and 14 patients with MET reported in previous literature were also reviewed. RESULTS: ① Female, left ear predominance in MET, and the most common symptoms were otorrhea and hearing loss. ② On CT and MRI, the MET presented as an irregular soft tissue mass that was heterogeneous, with fatty tissue and involved multiple sites, and the ET and tympanum were correspondingly expanded and locally destroyed. ③ Mictotia with MET in two patients was presented, which was the first report. CONCLUSION: MET has female sex and left ear predominance. CT and MRI can be used to diagnose MET and display its extent and its relationship to the carotid canal in detail. Complete surgical excision is the definitive treatment.


Assuntos
Neoplasias da Orelha , Teratoma , Humanos , Feminino , Estudos Retrospectivos , Neoplasias da Orelha/diagnóstico por imagem , Neoplasias da Orelha/cirurgia , Orelha Média/diagnóstico por imagem , Orelha Média/patologia , Teratoma/diagnóstico por imagem , Teratoma/cirurgia , Teratoma/patologia , Imageamento por Ressonância Magnética
6.
Zool Res ; 43(4): 634-647, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35838034

RESUMO

As an important evolutionary innovation and unique organ, the rumen has played a crucial role in ruminant adaptation to complex ecological environments. However, the cellular basis of its complex morphology and function remains largely unknown. In this study, we identified eight major cell types from seven representative prenatal and postnatal rumen samples using ~56 600 single-cell transcriptomes. We captured the dynamic changes and high heterogeneity in cellular and molecular profiles before, during, and after the appearance of keratinized stratified squamous epithelium with neatly arranged papillae and functional maturity. Basal cells, keratinocytes, differentiating keratinocytes, terminally differentiated keratinocytes, and special spinous cells provided the cellular basis for rumen epithelium formation. Notably, we obtained clear evidence of two keratinization processes involved in early papillogenesis and papillae keratinization and identified TBX3 as a potential marker gene. Importantly, enriched stratum spinosum cells played crucial roles in volatile fatty acid (VFA) metabolism and immune response. Our results provide a comprehensive transcriptional landscape of rumen development at single-cell resolution, as well as valuable insight into the interactions between dietary metabolism and the rumen.


Assuntos
Rúmen , Transcriptoma , Animais , Dieta/veterinária , Epitélio/metabolismo , Ácidos Graxos Voláteis/metabolismo , Rúmen/metabolismo , Ovinos/genética
7.
BJR Open ; 2(1): 20200005, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33178972

RESUMO

OBJECTIVE: To explore the otoscopy, CT and MRI features of spontaneous temporomandibular joint(TMJ)herniation(STMJH) into the external auditory canal (EAC) through the persistent foramen of Huschke (PFH). METHODS: 15 cases diagnosed STMJH were collected. The otoscopy, CT data of 15 cases and MRI data of 6 cases were retrospectively reviewed. RESULTS: Otoscopy revealed a mass located in the anterior wall of the bony EAC that moved forwards and backwards during mouth opening and closing, respectively. CT showed a soft mass with bony defect in the anterior wall of the EAC, with no enhancement; the bony defect margin was well defined in all cases. The bone adjacent to the PFH was pressed and partially wrapped around the soft mass, as if "holding a ball," in seven cases. Pseudobone shell around the soft mass was observed in eight cases. Six cases included MRI scans, which showed TMJ soft tissue herniated into the EAC. CONCLUSION: STMJHs have unique otoscopic, CT and MRI features. The examination strategy recommended is dynamic otoscopy and conventional CT, MRI can be chosen when the herniation is complicated by infection or otitis externa or when the patient has TMJ dysfunction; conservative management and follow-up observations are the main treatment strategy recommended. ADVANCES IN KNOWLEDGE: Mechanical stress of TMJ on the EAC is thought to cause herniation and the special CT features, the location and size of the PFH, especially the location, are the major risk factors for TMJ herniation in patients with FH.

8.
Exp Neurol ; 300: 135-148, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29126889

RESUMO

The glutamatergic projection from the motor cortex to the subthalamic nucleus (STN) constitutes the cortico-basal ganglia circuit and plays a critical role in the control of movement. Emerging evidence shows that the cortico-STN pathway is susceptible to dopamine depletion. Specifically in Parkinson's disease (PD), abnormal electrophysiological activities were observed in the motor cortex and STN, while the STN serves as a key target of deep brain stimulation for PD therapy. However, direct morphological changes in the cortico-STN connectivity in response to PD progress are poorly understood at present. In the present study, we used a trans-synaptic anterograde tracing method with herpes simplex virus-green fluorescent protein (HSV-GFP) to monitor the cortico-STN connectivity in a rat model of PD. We found that the connectivity from the primary motor cortex (M1) to the STN was impaired in parkinsonian rats as manifested by a marked decrease in trans-synaptic infection of HSV-GFP from M1 neurons to STN neurons in unilateral 6-hydroxydopamine (6-OHDA)-lesioned rats. Ultrastructural analysis with electron microscopy revealed that excitatory synapses in the STN were also impaired in parkinsonian rats. Glutamatergic terminals identified by a specific marker (vesicular glutamate transporter 1) were reduced in the STN, while glutamatergic neurons showed an insignificant change in their total number in both the M1 and STN regions. These results indicate that the M1-STN glutamatergic connectivity is downregulated in parkinsonian rats. This downregulation is mediated probably via a mechanism involving the impairments of excitatory terminals and synapses in the STN.


Assuntos
Córtex Motor/metabolismo , Oxidopamina/toxicidade , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/metabolismo , Núcleo Subtalâmico/metabolismo , Proteína Vesicular 1 de Transporte de Glutamato/metabolismo , Animais , Glutamatos/metabolismo , Locomoção/fisiologia , Masculino , Córtex Motor/efeitos dos fármacos , Córtex Motor/patologia , Vias Neurais/efeitos dos fármacos , Vias Neurais/metabolismo , Vias Neurais/patologia , Doença de Parkinson Secundária/patologia , Ratos , Ratos Sprague-Dawley , Núcleo Subtalâmico/efeitos dos fármacos , Núcleo Subtalâmico/patologia
9.
Oncotarget ; 7(32): 52179-52194, 2016 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-27438148

RESUMO

Type 2 diabetes mellitus is often complicated by osteoporosis, a process which may involve osteoblast autophagy. As melatonin suppresses autophagy under certain conditions, we its investigated the effects on bone autophagy during diabetes. We first assessed different body parameters in a diabetic rat model treated with various concentrations of melatonin. Dynamic biomechanicalmeasurements, bone organization hard slice dyeing and micro-CT were used to observe the rat bone microstructure, and immunohistochemistry was used to determine levels of autophagy biomarkers. We also performed in vitro experiments on human fetal osteoblastic (hFOB1.19) cells cultured with high glucose, different concentrations of melatonin, and ERK pathway inhibitors. And we used Western blotting and immunofluorescence to measure the extent of osteogenesis and autophagy. We found that melatonin improved the bone microstructure in our rat diabetes model and reduced the level of autophagy(50 mg/kg was better than 100 mg/kg). Melatonin also enhanced osteogenesis and suppressed autophagy in osteoblasts cultured at high glucose levels (10 µM was better than 1 mM). This suggests melatonin may reduce the level of autophagy in osteoblasts and delay diabetes-induced osteoporosis by inhibiting the ERK signaling pathway.


Assuntos
Autofagia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/complicações , Melatonina/farmacologia , Osteoporose/prevenção & controle , Animais , Diabetes Mellitus Experimental/complicações , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
10.
Microb Biotechnol ; 9(2): 257-68, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26833450

RESUMO

The objective of this research was to compare the composition of bacterial microbiota associated with the ruminal content (RC), ruminal epithelium (RE) and faeces of Holstein dairy cows. The RC, RE and faecal samples were collected from six Holstein dairy cows when the animals were slaughtered. Community compositions of bacterial 16S rRNA genes from RC, RE and faeces were determined using a MiSeq sequencing platform with bacterial-targeting universal primers 338F and 806R. UniFrac analysis revealed that the bacterial communities of RC, RE and faeces were clearly separated from each other. Statistically significant dissimilarities were observed between RC and faeces (P = 0.002), between RC and RE (P = 0.003), and between RE and faeces (P = 0.001). A assignment of sequences to taxa showed that the abundance of the predominant phyla Bacteroidetes was lower in RE than in RC, while a significant higher (P < 0.01) abundance of Proteobacteria was present in RE than in RC. When compared with the RC, the abundance of Firmicutes and Verrucomicrobia was higher in faeces, and RC contained a greater abundance of Bacteroidetes and Tenericutes. A higher proportions of Butyrivibrio and Campylobacter dominated RE as compared to RC. The faecal microbiota was less diverse than RC and dominated by genera Turicibacter and Clostridium. In general, these findings clearly demonstrated the striking compositional differences among RC, RE and faeces, indicating that bacterial communities are specific and adapted to the harbouring environment.


Assuntos
Bactérias/classificação , Biota , Epitélio/microbiologia , Fezes/microbiologia , Rúmen/microbiologia , Animais , Bactérias/genética , Bovinos , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(5): 1340-4, 2016 May.
Artigo em Chinês | MEDLINE | ID: mdl-30001002

RESUMO

In the smoothing pretreatment for the quantitative analysis of hydrocarbon mixed gases by Fourier transform infrared analysis (FTIR), the Savitzky- Golay filter is usually used as one of the smoothing preprocessing methods in the Fourier transform infrared spectrum data smoothing pretreatment. However, the parameters of the Savitzky-Golay filter such as the polynomial order and frame size are not easy to decide. There is no one unified choice basis. Users usually adopt multiple sets in the special data set to try, and then select a set of relatively optimal data as the optimizing parameters of the Savitzky-Golay filter. The optimal selection method of the Savitzky-Golay filter parameters was explored, and the concrete calculation equations were deduced according to the relation among the normalized cut-off frequency, the normalized beginning frequency of the stopband, the normalized first side lobe peak frequency of the stopband, the normalized first side lobe peak amplitude with the polynomial order and frame size of the Savitzky-Golay filter parameters. Then when the polynomial order and frame size are set as 8 and 11 respectively according the above conclusion and the characteristics of the actual spectral data, the Savitzky - Golay filter smoothing effect is optimum. Through the acquisition the concentration of 0.1%, 0.2%, 0.5%, 1%, 2%, 5% for the actual CH4 spectra, the relative maximum and minimum error of the raw spectra converted absorbance were 17.230 5% and 0.243 0% respectively, and the relative maximum and minimum error of the smooth spectra converted absorbance were 0.088 0% and 0.088 0% respectively in the second absorption peak. The relative error of converted absorbance was basically stable through the Savitzky-Golay filter after the spectral data preprocessing and it was relatively low, so, it laid a foundation for the late spectral data accurate qualitative and quantitative analysis.

12.
Jpn J Clin Oncol ; 45(9): 854-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26185140

RESUMO

OBJECTIVE: Fibulin-1 is a member of the fibulin gene family, characterized by tandem arrays of epidermal growth factor-like domains and a C-terminal fibulin-type module. Fibulin-1 plays important roles in a range of cellular functions including morphology, growth, adhesion and mobility. It acts as a tumor suppressor gene in cutaneous melanoma, prostate cancer and gastric cancer. However, whether fibulin-1 also acts as a tumor suppressor gene in lung adenocarcinoma remains unknown. We also determined the association of fibulin-1 expression with various clinical and pathological parameters, which would show its potential role in clinical prognosis. METHODS: We investigated and followed up 140 lung adenocarcinoma patients who underwent lung resection without pre- and post-operative systemic chemotherapy at the Affiliated Hospital of Nantong University from 2009 to 2013. Western blot assay and immunohistochemistry were used to evaluate the expression of fibulin-1 in lung adenocarcinoma tissues. We then analyzed the correlations between fibulin-1 expression and clinicopathological variables as well as the patients' overall survival rate. RESULTS: Both western blot assay and immunohistochemistry demonstrated that the level of fibulin-1 was downregulated in human lung adenocarcinoma tissues compared with that of normal lung tissues. Fibulin-1 expression significantly correlated with histological differentiation (P = 0.046), clinical stage (P< 0.01), lymph node status (P = 0.038) and expression of Ki-67 (P = 0.013). More importantly, multivariate analysis revealed that fibulin-1 was an independent prognostic marker for lung adenocarcinoma, and high expression of fibulin-1 was significantly associated with better prognosis of lung adenocarcinoma patients. CONCLUSIONS: The results supported our hypothesis that fibulin-1 can act as a prognostic factor in lung adenocarcinoma progression.


Assuntos
Adenocarcinoma/patologia , Proteínas de Ligação ao Cálcio/metabolismo , Neoplasias Pulmonares/patologia , Adenocarcinoma/mortalidade , Adenocarcinoma/cirurgia , Adenocarcinoma de Pulmão , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Western Blotting , Progressão da Doença , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Antígeno Ki-67/metabolismo , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/cirurgia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Prognóstico , Neoplasias Gástricas/mortalidade
13.
Med Sci Monit ; 21: 1617-24, 2015 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-26038188

RESUMO

BACKGROUND: Interleukin-1ß (IL-1ß) is an important inflammatory cytokine. The associations between IL-1ß gene -511C>T/+3954C>T polymorphisms and aggressive periodontitis (AgP) susceptibility have been conflicting. We therefore conducted a meta-analysis to investigate the association of IL-1ß genetic polymorphisms with susceptibility to AgP. MATERIAL AND METHODS: PubMed and Embase electronic databases were searched for relevant studies. Odds ratios (ORs) with 95% confidence interval (CIs) were used to assess the association between IL-1ß polymorphisms and AgP risk. Heterogeneity, publication bias, and sensitivity analysis were performed to guarantee the statistical power. RESULTS: Twenty published studies involving 965 patients and 1234 control subjects were included. No significant association between IL-1ß polymorphisms and AgP was found. For -511C>T (T vs. C: OR=0.966, 95%CI=0.696-1.341, P=0.869; CT vs. CC: OR=0.936, 95%CI=0.761-1.151; TT vs. CC: OR=0.892, 95%CI=0.464-1.715, P=0.719; CT+TT vs. CC: OR=1.026, 95%CI=0.795-1.323; TT vs. CC+CT: OR=0.864, 95%CI=0.436-1.713). For +3954C>T (T vs. C: OR=1.069, 95%CI=0.901-1.268; CT vs. CC: OR=0.921, 95%CI=0.699-1.212; TT vs. CC: OR=1.064, 95%CI=0.747-1.515; CT+TT vs. CC: OR=0.990, 95%CI=0.764-1.283; TT vs. CC+CT: OR=1.229, 95%CI=0.919-1.643). Subgroup analyses were conducted with HWE, ethnicity, and study design, and no significant association was detected. CONCLUSIONS: These results demonstrate that IL-1ß -511C>T and +3954C>T polymorphisms are not the risk factors for developing AgP.


Assuntos
Periodontite Agressiva/genética , Predisposição Genética para Doença/genética , Interleucina-1beta/genética , Polimorfismo de Nucleotídeo Único/genética , Estudos de Associação Genética , Humanos , Razão de Chances , PubMed
14.
Fitoterapia ; 104: 1-6, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25987318

RESUMO

One new 19-norbufadienolide (1) and one new bufogargarizin (2), together with twelve known bufadienolides (3-14, resp.) were isolated from Chan Su, a traditional Chinese medicine that is used in the treatment of cancer. Their structures were elucidated on the basis of detailed spectroscopic analysis and comparison of corresponding data that is previously reported. The cytotoxic activities of the isolated compounds were evaluated on HeLa and A549 cell lines. Though 1 and 2 showed weak cytotoxic activities on both cell lines, compounds 4 and 5 showed lower IC50 values than bufalin, the most widely studied bufadienolide in Chan Su. Furthermore, four 3-ester derivatives (15-18) of compound 4 were synthesized and their cytotoxic activities were also evaluated. Analysis of the structure-activity relationship indicated that bufadienolides with aldehyde group at C-10 or α-hydroxyl group at C-11 exhibit stronger cytotoxic activities on both cell lines. The cytotoxic activity of arenobufagin-3-ester derivative 17 was 4-fold higher than compound 4.


Assuntos
Bufanolídeos/química , Animais , Bufanolídeos/isolamento & purificação , Bufonidae , Linhagem Celular Tumoral/efeitos dos fármacos , Células HeLa/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Medicina Tradicional Chinesa , Estrutura Molecular , Relação Estrutura-Atividade
15.
Acta Pharmacol Sin ; 36(5): 627-43, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25891082

RESUMO

AIM: Tanshinol is an important catechol in the antianginal herb Salvia miltiorrhiza roots (Danshen). This study aimed to characterize tanshinol methylation. METHODS: Metabolites of tanshinol were analyzed by liquid chromatography/mass spectrometry. Metabolism was assessed in vitro with rat and human enzymes. The major metabolites were synthesized for studying their interactions with drug metabolizing enzymes and transporters and their vasodilatory properties. Dose-related tanshinol methylation and its influences on tanshinol pharmacokinetics were also studied in rats. RESULTS: Methylation, preferentially in the 3-hydroxyl group, was the major metabolic pathway of tanshinol. In rats, tanshinol also underwent considerable 3-O-sulfation, which appeared to be poor in human liver. These metabolites were mainly eliminated via renal excretion, which involved tubular secretion mainly by organic anion transporter (OAT) 1. The methylated metabolites had no vasodilatory activity. Entacapone-impaired methylation did not considerably increase systemic exposure to tanshinol in rats. The saturation of tanshinol methylation in rat liver could be predicted from the Michaelis constant of tanshinol for catechol-O-methyltransferase (COMT). Tanshinol had low affinity for human COMT and OATs; its methylated metabolites also had low affinity for the transporters. Tanshinol and its major human metabolite (3-O-methyltanshinol) exhibited negligible inhibitory activities against human cytochrome P450 enzymes, organic anion transporting polypeptides 1B1/1B3, multidrug resistance protein 1, multidrug resistance-associated protein 2, and breast cancer resistance protein. CONCLUSION: Tanshinol is mainly metabolized via methylation. Tanshinol and its major human metabolite have low potential for pharmacokinetic interactions with synthetic antianginal agents. This study will help define the risk of hyperhomocysteinemia related to tanshinol methylation.


Assuntos
Ácidos Cafeicos/farmacocinética , Fármacos Cardiovasculares/farmacocinética , Medicamentos de Ervas Chinesas/farmacocinética , Fígado/enzimologia , Salvia miltiorrhiza/química , Administração Oral , Animais , Biotransformação , Ácidos Cafeicos/administração & dosagem , Ácidos Cafeicos/isolamento & purificação , Ácidos Cafeicos/toxicidade , Fármacos Cardiovasculares/administração & dosagem , Fármacos Cardiovasculares/isolamento & purificação , Fármacos Cardiovasculares/toxicidade , Catecol O-Metiltransferase/metabolismo , Cromatografia Líquida , Sistema Enzimático do Citocromo P-450/metabolismo , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/toxicidade , Interações Ervas-Drogas , Humanos , Injeções Intravenosas , Túbulos Renais/metabolismo , Masculino , Espectrometria de Massas , Proteínas de Membrana Transportadoras/metabolismo , Metilação , Microssomos Hepáticos/enzimologia , Proteína 1 Transportadora de Ânions Orgânicos/metabolismo , Fitoterapia , Raízes de Plantas , Plantas Medicinais , Ratos Sprague-Dawley , Eliminação Renal , Sulfatos/metabolismo
16.
Front Microbiol ; 6: 167, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25784904

RESUMO

High-grain (HG) feeding used in intensive goat production can affect the physiology of the rumen wall, but the changes induced in the epimural bacterial community and host Toll-like receptors (TLRs) are not well understood. In this study, 10 male goats were randomly allocated to two groups and fed either a hay diet (0% grain; n = 5) or an HG diet (65% grain; n = 5). The changes in the ruminal epithelial bacterial community and expression of TLRs during long-term (7 weeks) HG feeding were determined using pyrosequencing and quantitative real-time polymerase chain reaction. Principal coordinate analysis and analysis of molecular variance (AMOVA) results showed that HG feeding caused a strong shift in bacterial composition and structure. At the genus level, our data revealed that it increased the relative abundance of taxa Butyrivibrio, unclassified Clostridiales, Mogibacterium, unclassified Anaerolineaceae, and Succiniclasticum, and decreased the proportion of unclassified Ruminococcaceae, unclassified Rikenellaceae, unclassified Erysipelotrichaceae, Howardella, and unclassified Neisseriaceae. The HG-fed goats also exhibited upregulation of the relative mRNA expression of TLR2, TLR3, and TLR5 in the rumen epithelium (P < 0.05). Correlation analysis revealed that the increase in TLR expression was associated with changes in the relative abundance of ruminal epithelial bacteria. This study provides a first insight into the adaptive response of ruminal epithelial bacterial populations to HG feeding in goats and shows that these changes were associated with alterations in TLR expression. These findings provide new insight into understanding of host-microbial relationships in ruminants.

17.
Fitoterapia ; 101: 218-23, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25617784

RESUMO

Two new sesquiterpene lactone dimers, neojaponicone B (1) and inulanolide E (2) along with five known sesquiterpene lactone dimers (3-7, resp.) were isolated from the aerial parts of Inula japonica Thunb. The chemical structures of 1 and 2 were elucidated by detailed spectroscopic analysis. The relative configuration of 2 was confirmed by biomimetic transformation from the known sesquiterpene lactone dimer inulanolide A (3). The cytotoxicities of the isolated sesquiterpene lactone dimers were evaluated against 6T-CEM and Jurkat cell lines. All compounds showed potent cytotoxicities with IC50 value of 2.2-5.9µm.


Assuntos
Antineoplásicos Fitogênicos/química , Inula/química , Lactonas/química , Sesquiterpenos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Concentração Inibidora 50 , Lactonas/isolamento & purificação , Estrutura Molecular , Componentes Aéreos da Planta/química , Sesquiterpenos/isolamento & purificação
18.
Nat Prod Res ; 29(7): 656-62, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25428208

RESUMO

Mangosteen fruit is fermented with five different strains (i.e. GRE (Y1), Lalvin RC212 (Y2), Lalvin D254 (Y3), CGMCC2.23 (Y4) and CGMCC2.4 (Y5)) of the yeast Saccharomyces cerevisiae to make mangosteen wines. A total of 36 volatile compounds of the mangosteen wines were identified by gas chromatography-mass spectrometry and gas chromatography-pulsed flame photometric detection. A total of 35 odour-active compounds were identified by gas chromatography-olfactometry analysis and by the detection frequency (DF) method. The compounds with high DF values included ethyl octanoate, ethyl hexanoate and 3-methyl-2-butene-1-thiol. Principal component analysis was used to characterise the differences of the flavour profiles of those mangosteen wines. The result demonstrated that the samples could be divided into three groups that were associated closely with aroma-active compounds.


Assuntos
Frutas/química , Garcinia mangostana/química , Odorantes/análise , Compostos Orgânicos Voláteis/análise , Vinho/análise , Fermentação , Cromatografia Gasosa-Espectrometria de Massas , Olfatometria , Análise de Componente Principal , Saccharomyces cerevisiae
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(7): 1836-9, 2014 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-25269291

RESUMO

In the multicomponent mixture hydrocarbon gases Fourier transform infrared (FTIR) quantitative analysis, especially for light alkane gases, it is not easy to establish the quantitative analysis model because their IR spectra absorption peaks are seriously overlapped. Aiming at this problem, the Tikhonov regularization algorithm was used to select the characteristic wavelengths for seven kinds of light alkane mixture gases FTIR which are composed with methane, ethane, propane, iso-butane, n-butane, iso-pentane and n-pentane. And then the wavelength selection was used to establish the quantitative analysis model. By comparing the analysis characteristics wavelength selection and TR parameters optimization of the mixed gases in the infrared all wave band, the first absorption peak band and the second peak band, the characteristic wavelength of 7 kinds of gases were selected by Tikhonov algorithm. The wavelength selection and Tikhonov regularization parameters were used to test the actual measured methane spectral data, and then we got that with other gas components the max cross sensitivity was 11.153 7%, the minimum cross sensitivity was 1.239 7%, and the root mean square prediction error was 0.004 8. The Tikhonov regularization algorithm effectively enhanced the accuracy in the light alkane mixed gas quantitative analysis. The feasibility of alkane gases mixture Fourier transform infrared spectrum wavelength selection was preliminarily verified by using the Tikhonov regularization algorithm.

20.
Cutis ; 94(2): E1-2, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25184649
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