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1.
Angew Chem Int Ed Engl ; 59(16): 6473-6481, 2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-31999022

RESUMO

Despite the growing importance of volatile functionalized diazoalkanes in organic synthesis, their safe generation and utilization remain a formidable challenge because of their difficult handling along with storage and security issues. In this study, we developed a bench-stable difluoroacetaldehyde N-triftosylhydrazone (DFHZ-Tfs) as an operationally safe diazo surrogate that can release in situ two low-molecular-weight diazoalkanes, diazoacetaldehyde (CHOCHN2 ) or difluorodiazoethane (CF2 HCHN2 ), in a controlled fashion under specific conditions. DFHZ-Tfs has been successfully employed in the Fe-catalyzed cyclopropanation and Doyle-Kirmse reactions, thus highlighting the synthetic utility of DFHZ-Tfs in the efficient construction of molecule frameworks containing CHO or CF2 H groups. Moreover, the reaction mechanism for the generation of CHOCHN2 from CF2 HCHN2 was elucidated by density functional theory (DFT) calculations.

2.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(3): 253-256, 2019 Mar 10.
Artigo em Chinês | MEDLINE | ID: mdl-30835358

RESUMO

OBJECTIVE: To delineate laboratory and clinical characteristics of a case with chronic myelogenous leukemia (CML) and co-occurrence of t(9;22)(q34;q11) and t(8;21)(q22;q22). METHODS: The patient was subjected to cytogenetic, molecular, morphological and immunophenotypic analyses. RESULTS: Cytogenetic analysis revealed presence of t(8;21)(q22;q22) in addition to t(9;22)(q34;q11) in the patient. Chimeric BCR/ABL and AML1/ETO genes were detected by fluorescence in situ hybridization (FISH). Transcripts of BCR/ABL210 and AML1/ETO fusion genes were detected by relative quantity PCR. Morphological study suggested that the patient was at the chronic phase of CML. No significant immunophenotypic abnormality was detected by flow cytometry. CONCLUSION: Co-occurrence of t(8;21)(q22;q22) and t(9;22)(q34;q11) is rare in CML. Only 5 similar cases have been described previously. This case suggested that chromosomal alterations may precede morphological, flow cytometric and clinical changes and accelerate progression of the disease.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Translocação Genética , Aberrações Cromossômicas , Cromossomos Humanos , Proteínas de Fusão bcr-abl , Humanos , Hibridização in Situ Fluorescente , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética
3.
Int J Biol Macromol ; 258(Pt 2): 128997, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38154713

RESUMO

The Tachinidae is one of the most speciose families in Diptera, and the exclusively parasitoid species play an important role in regulating populations of many herbivorous insects in ecosystems, including many agricultural pests. To better comprehend the characteristics and evolution of the mitochondrial genome for the Tachinidae, we are adding a massive amount of new molecular data by assembling the mitogenomes for 71 genera and 135 species from all four tachinid subfamilies through next-generation sequencing, and we are presenting the most comprehensive mitogenomic phylogenetic analysis of this family so far. Extensive rearrangements observed in the mitogenome of Admontia podomyia (Exoristinae) are unique for the entire suborder Cyclorrhapha. The rearrangement pattern suggests that the process involved a tandem duplication of the complete mitogenome, followed by both random and nonrandom loss of one copy of each gene. Additionally, five minor mitogenome rearrangements are discovered and described in three subfamilies. We present the largest species-level phylogenetic hypothesis for Tachinidae to date, based on mitogenomes of 152 species of Tachinidae, representing all four subfamilies and with five non-tachinid outgroups. Our analyses support the monophyly of the Tachinidae and most tribes and genera were recovered with good support, but the higher-level phylogenetic relationships within Tachinidae were poorly resolved, indicating that mitogenome data alone are not enough to unambiguously resolve the deeper phylogenetic relationships within Tachinidae.


Assuntos
Dípteros , Genoma Mitocondrial , Animais , Dípteros/genética , Ecossistema , Filogenia
4.
Zhong Yao Cai ; 35(1): 102-5, 2012 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-22734421

RESUMO

OBJECTIVE: To investigate the effect of saponin from Tupistra chinensis Baker (STCB) on lethal toxicity of endotoxin in mice and explore the underlying mechanism. METHODS: Mouse models of endotoxin-induced death and endotoximia were established by intraperitoneal administration of KM mice with lipopolysaccharides (LPS) from Pseudomonas aeruginosa in doses of 60 mg/kg and 10 mg/kg respectively. Mouse survival rate and survival time were recorded and the serum levels of interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) in endotoximia mice were measured by enzyme-linked immunosorbent assay (ELISA). Mouse peritoneal exudate cells induced by LPS were used as an in vitro inflammatory model,which was then intervened with STCB and the levels of IL-1beta and TNF-alpha in the culture supernatants were measured by ELISA. RESULTS: The survival rates of mice prophylactically treated with STCB (200 and 400 mg/kg, in 5 consecutive days) were slightly higher compared with that in model group,but no statistical difference was observed (P>0.05). The survival time was much longer in the treated group (P<0.05). The serum levels of IL-1beta and TNF-alpha in STCB-treated mice (200 and 400 mg/kg, in 5 consecutive days) were significantly lower compared with those in model group (P<0.05). STCB (20 and 40 microg/mL) remarkably inhibited LPS-induced IL-1beta and TNF-alpha production by peritoneal exudate cells in vitro (P<0.05). CONCLUSION: Saponin from Tupistra chinensis showed beneficial effect on the prevention of mice from lipopolysaccharides-induced death, in which down regulation of IL-1beta and TNF-alpha expression might be involved.


Assuntos
Endotoxemia/prevenção & controle , Endotoxinas/antagonistas & inibidores , Endotoxinas/intoxicação , Interleucina-1beta/metabolismo , Saponinas/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Células Cultivadas , Dexametasona/farmacologia , Modelos Animais de Doenças , Regulação para Baixo , Endotoxemia/induzido quimicamente , Endotoxemia/metabolismo , Endotoxinas/farmacologia , Ensaio de Imunoadsorção Enzimática , Feminino , Interleucina-1beta/sangue , Liliaceae , Lipopolissacarídeos/administração & dosagem , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos , Distribuição Aleatória , Taxa de Sobrevida , Fator de Necrose Tumoral alfa/sangue
5.
Zhong Yao Cai ; 34(8): 1277-80, 2011 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-22233044

RESUMO

OBJECTIVE: To study the optimal extraction process of immune active polysaccharides from Fomes fomentarius by introduction of ultrasonication. METHODS: An orthogonal experimental design of L9 (3(4)) was used to investigate the effects of ultrasonication time, extraction temperature and extraction time on the extraction ratio, sugar content and immune stimulating activity (mouse splenocyte metabolic activity measured with MTT colorimetry) of the polysaccharides and the optimal extraction process was evaluated. RESULTS: Ultrasonication treatment had the most remarkable effect on the immune stimulating activity of the polysaccharides. The optimal extraction process for extraction of immune active polysaccharides was as follows: ultrasonication for 30min, extraction temperature at 80 degrees C and water extraction time for 2h. CONCLUSION: Ultrasonication can be used as a useful technique for extraction of immune active polysaccharides from Fomes fomentarius.


Assuntos
Coriolaceae/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Ultrassom , Animais , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Polissacarídeos/análise , Baço/citologia , Baço/efeitos dos fármacos , Baço/imunologia , Tecnologia Farmacêutica/métodos , Temperatura , Fatores de Tempo , Água/química
6.
Artigo em Chinês | MEDLINE | ID: mdl-19334552

RESUMO

The method of event-related potentials (ERP) was used to study the gender difference in face recognition. The stimuli in the experiment were 10 upright and 10 inverted face photos. The subjects, half female and half male, were asked to judge whether the face was upright or inverted. The results showed that the N170 wave forms were observed in the occipito-temporal regions and they were found exhibiting brain's right hemispheric dominance. The stimuli of different gender photos were noticed to have no significant impact on the N170 wave forms, but there were significant differentce in the amplitude and latency period of N170 between different gender participants. Moreover, there was marked difference in the latency period of the male participants watching the same gender face and different gender face. Similar results were not found in the ERP's latency period of female participants.


Assuntos
Encéfalo/fisiologia , Potenciais Evocados , Face , Percepção de Forma/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Adulto , Eletroencefalografia , Expressão Facial , Feminino , Humanos , Masculino , Reconhecimento Psicológico , Fatores Sexuais , Adulto Jovem
7.
Clin Neurophysiol ; 119(6): 1232-41, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18396454

RESUMO

OBJECTIVE: Schizophrenics are usually unable to perform well on cognitive tasks due to disturbances in cortical information processing that are observable as abnormalities in electroencephalogram (EEG) signals. However, whether such cortical disturbances can be assessed by quantitative EEG analysis remains unclear. The purpose of this study was to characterize EEG disturbances, using the Lempel-Ziv complexity (LZC), in the subjects with schizophrenia at rest or while performing mental arithmetic tasks. The results were compared to those from the subjects with depression and with healthy controls. METHODS: The subjects included 62 schizophrenia patients, 48 depression patients and 26 age-matched healthy controls. EEG was recorded under two conditions: (i) resting with eyes closed, and (ii) a mentally active condition wherein the subjects were asked to subtract 7 from 100 iteratively with their eyes closed. EEG signals were analyzed by LZC and conventional spectral methods. RESULTS: In all the groups, LZC of EEG decreased during the mental arithmetic compared with those under the resting conditions. Both the schizophrenia and the depression groups had a higher LZC (p<0.05) than the controls. Also, the schizophrenia group had a lower LZC (p<0.05) than the depression group during the mental arithmetic task as well as during the resting state. Significant differences in LZC, at some symmetrically located loci (FP1/FP2, F7/F8), between the two hemispheres were found in all the patient groups only during the arithmetic task. CONCLUSIONS: Compared with conventional spectral analysis, LZC was more sensitive to both the power spectrum and the temporal amplitude distribution. LZC was associated with the ability to attend to the task and adapt the information processing system to the cognitive challenge. Thus, it would be useful in studying the disturbances in the cortical information processing patients with depression or schizophrenia. SIGNIFICANCE: LZC of EEG is associated with mental activity. Thus, LZC analysis can be an important tool in understanding the pathophysiology of schizophrenia and depression in future studies.


Assuntos
Córtex Cerebral/fisiopatologia , Depressão/complicações , Eletroencefalografia , Esquizofrenia/complicações , Adulto , Análise de Variância , Mapeamento Encefálico , Estudos de Casos e Controles , Depressão/patologia , Feminino , Lateralidade Funcional , Humanos , Masculino , Matemática , Processos Mentais/fisiologia , Esquizofrenia/patologia , Análise Espectral
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