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1.
J Synchrotron Radiat ; 31(Pt 3): 635-645, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38656774

RESUMO

With the development of synchrotron radiation sources and high-frame-rate detectors, the amount of experimental data collected at synchrotron radiation beamlines has increased exponentially. As a result, data processing for synchrotron radiation experiments has entered the era of big data. It is becoming increasingly important for beamlines to have the capability to process large-scale data in parallel to keep up with the rapid growth of data. Currently, there is no set of data processing solutions based on the big data technology framework for beamlines. Apache Hadoop is a widely used distributed system architecture for solving the problem of massive data storage and computation. This paper presents a set of distributed data processing schemes for beamlines with experimental data using Hadoop. The Hadoop Distributed File System is utilized as the distributed file storage system, and Hadoop YARN serves as the resource scheduler for the distributed computing cluster. A distributed data processing pipeline that can carry out massively parallel computation is designed and developed using Hadoop Spark. The entire data processing platform adopts a distributed microservice architecture, which makes the system easy to expand, reduces module coupling and improves reliability.

2.
Zhonghua Nan Ke Xue ; 29(1): 43-48, 2023 Jan.
Artigo em Zh | MEDLINE | ID: mdl-37846831

RESUMO

OBJECTIVE: To investigate the outcomes of intracytoplasmic sperm injection (ICSI) in the treatment of special types of teratozoospermia such as globozoospermia, acephalic spermatozoa syndrome (ASS) and multiple morphological abnormalities of sperm flagella (MMAF). METHODS: We retrospectively analyzed the clinical data on 7 cases of globozoospermia (group A), 6 cases of ASS (group B) and 21 cases of MMAF (group C) treated by ICSI from January 2011 to January 2021, all confirmed with pathogenic or likely pathogenic gene variations. We compared the age, body mass index (BMI), sperm parameters, number of mature oocytes, and rates of fertilization, high-quality embryos, clinical pregnancy, live birth and spontaneous abortion among the three groups of patients. RESULTS: There were no statistically significant differences in the age, BMI and number of metaphase Ⅱ (MⅡ) oocytes among the three groups (P > 0.05). Sperm concentration and motility were dramatically higher (P < 0.01) while the rates of fertilization, clinical pregnancy and live birth remarkably lower in group A than in B and C (P < 0.01). No statistically significant difference was observed in the spontaneous abortion rate among the three groups (P > 0.05). CONCLUSION: ICSI can achieve relatively satisfactory outcomes of clinical pregnancy in patients with ASS or MMAF, but only a low fertilization rate or no fertilization at all in those with globozoospermia even if treated by artificial oocyte activation.


Assuntos
Aborto Espontâneo , Infertilidade Masculina , Teratozoospermia , Gravidez , Feminino , Humanos , Masculino , Injeções de Esperma Intracitoplásmicas , Teratozoospermia/genética , Infertilidade Masculina/genética , Estudos Retrospectivos , Sêmen , Espermatozoides , Oócitos
3.
Zhonghua Nan Ke Xue ; 24(1): 6-13, 2018.
Artigo em Zh | MEDLINE | ID: mdl-30157353

RESUMO

OBJECTIVE: To assess the risk of male infertility in the offspring conceived through assisted reproductive technology (ART) byin vitroinductionof the differentiation of embryonic stem cells (ESCs) derived from the embryos of the couples with male asthenozoospermia and Robertsonian translocation (RT) into germ cells. METHODS: We established a CCRM16ESC line with the karyotype of 46, XY, +14, rob(13; 14) (q10; q10) from the embryo donated by a patientwithasthenozoospermiaand RT and his wife by isolation of the inner cell mass of blastula, culturing, passaging, and amplification,followed by in vitro induction and differentiationof the ESCs into germ cells with ratinoic acid(RA) at 2 mol/L. Then, we analyzed the process of differentiation and the expressions of its related genes and compared them with those in the normal CCRM23ESCs. RESULTS: CCRM16 showed the typical characteristics of ESCs, expressing the pluripotency makers of NANOG, OCT4, TRA-1-181 and SSEA4, forming embryoid bodies, and differentiating into three germlayer tissues in vitro and in vivo. Intervention with 2 mol/LRAinduced direct differentiation of the ESCs into germ cells. The expressions of the primordial germ cell marker geneDAZLand the meiosis marker geneSCP3were markedly decreased in the CCRM16 as compared with those in the normal CCRM23 ESCs. CONCLUSIONS: The CCRM16ESC linewith the karyotype of46, XY, +14, rob(13; 14) (q10; q10) has thetypical characteristics of ESCs but an abnormal process of differentiation into germ cells in the early stage. In vitroinductionof the differentiation of ESCs into germ cells can be used for assessing the risk of male infertility in the offspring conceived through ART for asthenozoospermia patients.


Assuntos
Cariótipo Anormal , Astenozoospermia/patologia , Massa Celular Interna do Blastocisto , Diferenciação Celular/genética , Cromossomos Humanos 13-15/genética , Células-Tronco Embrionárias/citologia , Células Germinativas/citologia , Infertilidade Masculina/etiologia , Translocação Genética/genética , Animais , Astenozoospermia/genética , Linhagem Celular , Marcadores Genéticos , Humanos , Masculino , Técnicas de Reprodução Assistida , Risco , Antígenos Embrionários Estágio-Específicos
4.
Zhongguo Dang Dai Er Ke Za Zhi ; 19(4): 405-409, 2017 Apr.
Artigo em Zh | MEDLINE | ID: mdl-28407826

RESUMO

OBJECTIVE: To analyze the clinical features of 6 children with Duchenne muscular dystrophy (DMD) and review related literature, and to provide a basis for early diagnosis and effective treatment of this disease. METHODS: A retrospective analysis was performed on the clinical data of 6 children with DMD who were admitted to the First Affiliated Hospital of Nanjing Medical University from January 2010 to October 2015. RESULTS: All the 6 cases were boys without a family history of DMD, and the age of diagnosis of DMD was 1.2-11.5 years. All patients had insidious onset and increases in alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, α-hydroxybutyrate dehydrogenase, creatine kinase (CK), and creatine kinase-MB, particularly CK, which was 3.3-107.2 times the normal level. Their gene detection results all showed DMD gene mutation. The gene detection results of two children's mothers showed that they carried the same mutant gene. The muscle biopsy in one case showed that the pathological changes confirmed the diagnosis of DMD. The level of CK in one case declined by 77.0% 5 days after umbilical cord blood mesenchymal stem cell transplantation. CONCLUSIONS: For boys with abnormal serum enzyme levels and motor function, DMD should be highly suspected. It should be confirmed by CK and DMD gene detection as soon as possible. And the progression of the disease could be delayed by early intervention for protecting the remaining normal muscle fibers.


Assuntos
Distrofia Muscular de Duchenne/genética , Criança , Pré-Escolar , Transplante de Células-Tronco de Sangue do Cordão Umbilical , Creatina Quinase/genética , Distrofina/genética , Humanos , Lactente , Masculino , Distrofia Muscular de Duchenne/terapia , Estudos Retrospectivos
5.
J Am Chem Soc ; 137(48): 15070-3, 2015 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-26555852

RESUMO

Development of an efficient hydrogen evolution reaction (HER) catalyst composed of earth-abundant elements is scientifically and technologically important for the water splitting associated with the conversion and storage of renewable energy. Herein we report a new class of Co-C-N complex bonded carbon (only 0.22 at% Co) for HER with a self-supported and three-dimensional porous structure that shows an unexpected catalytic activity with low overpotential (212 mV at 100 mA cm(-2)) and long-term stability, better than that of most traditional-metal catalysts. Experimental observations in combination with density functional theory calculations reveal that C and N hybrid coordination optimizes the charge distribution and enhances the electron transfer, which synergistically promotes the proton adsorption and reduction kinetics.

6.
Chem Biodivers ; 12(7): 1068-74, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26172327

RESUMO

Three new Δ(1) -3-ketosteroids characterized with a 9-OH, subergosterones A-C (1-3), together with five known analogs 4-8, were obtained from the gorgonian coral Subergorgia rubra collected from the South China Sea. The structures of 1-3, including their absolute configurations, were determined by comprehensive spectroscopic methods and electronic circular dichroism (ECD) experiments. Compounds 2 and 3 exhibited inhibitory antibacterial activities against Bacillus cereus with MIC values of 1.56 µM.


Assuntos
Antozoários/química , Antibacterianos/farmacologia , Bacillus cereus/efeitos dos fármacos , Cetosteroides/farmacologia , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Relação Dose-Resposta a Droga , Cetosteroides/química , Cetosteroides/isolamento & purificação , Testes de Sensibilidade Microbiana , Conformação Molecular , Relação Estrutura-Atividade
7.
World J Diabetes ; 15(6): 1254-1262, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38983810

RESUMO

BACKGROUND: The FreeStyle Libre flash glucose monitoring (FGM) system entered the Chinese market in 2017 to complement the self-monitoring of blood glucose. Due to its increased usage in clinics, the number of studies investigating its accuracy has increased. However, its accuracy has not been investigated in highland popu-lations in China. AIM: To evaluate measurements recorded using the FreeStyle Libre FGM system compared with capillary blood glucose measured using the enzyme electrode method in patients with type 2 diabetes (T2D) who had migrated within 3 mo from highlands to plains. METHODS: Overall, 68 patients with T2D, selected from those who had recently migrated from highlands to plains (within 3 mo), were hospitalized at the Department of Endocrinology from August to October 2017 and underwent continuous glucose monitoring (CGM) with the FreeStyle Libre FGM system for 14 d. Throughout the study period, fingertip capillary blood glucose was measured daily using the enzyme electrode method (Super GL, China), and blood glucose levels were read from the scanning probe during fasting and 2 h after all three meals. Moreover, the time interval between reading the data from the scanning probe and collecting fingertip capillary blood was controlled to < 5 min. The accuracy of the FGM system was evaluated according to the CGM guidelines. Subsequently, the factors influencing the mean absolute relative difference (MARD) of this system were analyzed by a multiple linear regression method. RESULTS: Pearson's correlation analysis showed that the fingertip and scanned glucose levels were positively correlated (R = 0.86, P = 0.00). The aggregated MARD of scanned glucose was 14.28 ± 13.40%. Parker's error analysis showed that 99.30% of the data pairs were located in areas A and B. According to the probe wear time of the FreeStyle Libre FGM system, MARD1 d and MARD2-14 d were 16.55% and 14.35%, respectively (t = 1.23, P = 0.22). Multiple stepwise regression analysis showed that MARD did not correlate with blood glucose when the largest amplitude of glycemic excursion (LAGE) was < 5.80 mmol/L but negatively correlated with blood glucose when the LAGE was ≥ 5.80 mmol/L. CONCLUSION: The FreeStyle Libre FGM system has good accuracy in patients with T2D who had recently migrated from highlands to plains. This system might be ideal for avoiding the effects of high hematocrit on blood glucose monitoring in populations that recently migrated to plains. MARD is mainly influenced by glucose levels and fluctuations, and the accuracy of the system is higher when the blood glucose fluctuation is small. In case of higher blood glucose level fluctuations, deviation in the scanned glucose levels is the highest at extremely low blood glucose levels.

8.
Can Respir J ; 2024: 5554886, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38584671

RESUMO

Objective: To investigate the mechanism through which Astragalus and Panax notoginseng decoction (APD) facilitates the treatment of ferroptosis-mediated pulmonary fibrosis. Materials and Methods: First, the electromedical measurement systems were used to measure respiratory function in mice; the lungs were then collected for histological staining. Potential pharmacologic targets were predicted via network pharmacology. Finally, tests including immunohistochemistry, reverse transcription-quantitative polymerase chain reaction, and western blotting were used to evaluate the relative expression levels of collagen, transforming growth factor ß, α-smooth muscle actin, hydroxyproline, and ferroptosis-related genes (GPX4, SLC7A11, ACSL4, and PTGS2) and candidates involved in the mediation of pathways associated with ferroptosis (Hif-1α and EGFR). Results: APD prevented the occurrence of restrictive ventilation dysfunction induced by ferroptosis. Extracellular matrix and collagen fiber deposition were significantly reduced when the APD group compared with the model group; furthermore, ferroptosis was attenuated, expression of PTGS2 and ACSL4 increased, and expression of GPX4 and SLC7A11 decreased. In the APD group, the candidates related to the mediation of ferroptosis (Hif-1α and EGFR) decreased compared with the model group. Discussion and Conclusions. APD may ameliorate restrictive ventilatory dysfunction through the inhibition of ferroptosis. This was achieved through the attenuation of collagen deposition and inflammatory recruitment in pulmonary fibrosis. The underlying mechanisms might involve Hif-1α and EGFR.


Assuntos
Ferroptose , Panax notoginseng , Fibrose Pulmonar , Animais , Camundongos , Fibrose Pulmonar/tratamento farmacológico , Ciclo-Oxigenase 2 , Colágeno , Receptores ErbB
9.
Mar Drugs ; 11(6): 2054-68, 2013 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-23752358

RESUMO

One new phenylalanine derivative 4'-OMe-asperphenamate (1), along with one known phenylalanine derivative (2) and two new cytochalasins, aspochalasin A1 (3) and cytochalasin Z24 (4), as well as eight known cytochalasin analogues (5-12) were isolated from the fermentation broth of Aspergillus elegans ZJ-2008010, a fungus obtained from a soft coral Sarcophyton sp. collected from the South China Sea. Their structures and the relative configurations were elucidated using comprehensive spectroscopic methods. The absolute configuration of 1 was determined by chemical synthesis and Marfey's method. All isolated metabolites (1-12) were evaluated for their antifouling and antibacterial activities. Cytochalasins 5, 6, 8 and 9 showed strong antifouling activity against the larval settlement of the barnacle Balanus amphitrite, with the EC50 values ranging from 6.2 to 37 µM. This is the first report of antifouling activity for this class of metabolites. Additionally, 8 exhibited a broad spectrum of antibacterial activity, especially against four pathogenic bacteria Staphylococcus albus, S. aureus, Escherichia coli and Bacillus cereus.


Assuntos
Antozoários/microbiologia , Aspergillus/química , Citocalasinas/farmacologia , Fenilalanina/farmacologia , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Aspergillus/isolamento & purificação , Bactérias/efeitos dos fármacos , Incrustação Biológica/prevenção & controle , China , Citocalasinas/química , Citocalasinas/isolamento & purificação , Fenilalanina/análogos & derivados , Fenilalanina/isolamento & purificação , Análise Espectral
10.
Zhonghua Nan Ke Xue ; 17(11): 977-83, 2011 Nov.
Artigo em Zh | MEDLINE | ID: mdl-22141266

RESUMO

OBJECTIVE: Sperm chromatin structure assay (SCSA), as a clinically practical technique for the analysis of DNA damage, is rarely reported in China. This study focuses on the correlation of DNA damage with the pregnancy rate of intrauterine insemination (IUI). METHODS: We performed semen analysis for 482 couples undergoing IUI, calculated the DNA fragmentation index (DFI) by SCSA, and observed the relationship between DFI and the pregnancy rate of IUI. RESULTS: Clinical pregnancy was achieved in 5 (5.26%) of the 95 cases with DFI > 25%, and in 59 (15.25%) of the 387 cases with DFI < or = 25%. Those with sperm DFI >25% had significantly lower rates of biochemical pregnancy and clinical pregnancy than those with DFI < or = 25% (OR: 0.37, 95% CI: 0.14 - 0.96 and OR: 0.38, 95% CI: 0.16 - 0.97). No significant differences were found in the DFI of 54 cases between the first and the second cycle ([15.05 +/- 7.98]% vs [17.25 +/- 12.18]%, P > 0.05). Sperm DFI was significantly negatively correlated with sperm concentration, sperm motility and total progressively motile sperm count (P < 0.01). CONCLUSION: The pregnancy rate of IUI is significantly lower in couples with DFI >25% than in those with DFI < or = 25%. Sperm DFI obtained from SCSA is partly correlated with sperm concentration and motility, and it is a robust predictor of the IUI outcome.


Assuntos
Cromatina , Fragmentação do DNA , Inseminação Artificial/métodos , Resultado da Gravidez/genética , Adulto , Estruturas Cromossômicas , Feminino , Humanos , Inseminação , Masculino , Gravidez , Taxa de Gravidez , Técnicas de Reprodução Assistida , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Adulto Jovem
11.
Nat Prod Res ; 35(21): 3970-3976, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32290694

RESUMO

A new α,ß-unsaturated 7-ketone sterol, 5ß,6ß-epoxy-3ß, 15α-dihydroxy-(22E,24R)-ergosta-8(14),22-dien-7-one (1), along with five known sterone derivatives, 5ß,6ß-epoxy-3ß,7α-dihydroxy-(22E,24R)-ergosta-8(14),22-dien-15-one (2), 5ß,6ß-epoxy-3ß,7α,9α-trihydroxy-(22E,24R)-ergosta-8(14),22-dien-15-one (3), 3ß,9α,15α-trihydroxy-(22E,24R)-10(5→4)-abeo-ergosta-6,8(14),22-trien-5-one (4), 3,15-dihydroxyl-(22E,24R)-ergosta-5,8(14),22-trien-7-one (5) and (22E,24R)-ergosta-4,6,8(14),22-tetraen-3,15-dione (6) were isolated from the mangrove-derived fungus Phomopsis sp. MGF222. Their structures were established on the basis of extensive spectroscopic data and comparison with the data of literature. Compound 2 showed weak antibacterial activity against Micrococcus tenuis with the MIC value of 28.2 (±0.52) µM. Compound 5 exhibited moderate antibacterial activity against Staphylococcus aureus with the MIC value of 14.6 (±0.47) µM.


Assuntos
Phomopsis , Rodófitas , Fungos , Cetonas , Estrutura Molecular , Esteróis/farmacologia
12.
Nat Prod Res ; 35(21): 4051-4057, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31960725

RESUMO

A new phenol derivative, 3-chloro-5-hydroxy-4-methoxyphenylacetic acid methyl ester (1), along with five known compounds methyl 4-hydroxyphenylacetate (2), cytosporone B (3), (R)-striatisporolide A (4), (R)-butanedioic acid (5) and ergosterol (6) were isolated from the mangrove-derived fungus Eupenicillium sp. HJ002. Their structures were established by spectroscopic methods, GIAO based 13C NMR chemical shift calculations and comparison with the data of literature. Compounds 1-5 were isolated from Xylocarpus granatum Koening-derived fungus for the first time.


Assuntos
Eupenicillium , Meliaceae , Fungos , Estrutura Molecular , Fenol
13.
J Asian Nat Prod Res ; 11(10): 851-5, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20183245

RESUMO

Two new metabolites, sarcophytonone (1) and sarcophytonamine (2), have been isolated from the Hainan soft coral Sarcophyton crassocaule. Their structures were elucidated on the basis of a detailed analysis of spectroscopic data, and by comparison of their NMR spectral data with those of the related model compounds.


Assuntos
Aminas/isolamento & purificação , Compostos de Anilina/isolamento & purificação , Antozoários/química , Quinonas/isolamento & purificação , Aminas/química , Compostos de Anilina/química , Animais , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Quinonas/química
14.
Chin Med J (Engl) ; 131(7): 770-775, 2018 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-29578119

RESUMO

BACKGROUND: Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) are common X-linked recessive neuromuscular disorders caused by mutations in dystrophin gene. Multiplex polymerase chain reaction (multiplex PCR) and multiplex ligation-dependent probe amplification (MLPA) are the most common methods for detecting dystrophin gene mutations. This study aimed to contrast the two methods and discern the genetic characterization of patients with DMD/BMD in Eastern China. METHODS: We collected 121 probands, 64 mothers of probands, and 15 fetuses in our study. The dystrophin gene was detected by multiplex PCR primarily in 28 probands, and MLPA was used in multiplex PCR-negative cases subsequently. The dystrophin gene of the remaining 93 probands and 62 female potential carriers was tested by MLPA directly. In fetuses, multiplex PCR and MLPA were performed on 4 fetuses and 10 fetuses, respectively. In addition, sequencing was also performed in 4 probands with negative MLPA. RESULTS: We found that 61.98% of the subjects had genetic mutations including deletions (50.41%) and duplications (11.57%). There were 43.75% of mothers as carriers of the mutation. In 15 fetuses, 2 out of 7 male fetuses were found to be unhealthy and 2 out of 8 female fetuses were found to be carriers. Exons 3-26 and 45-52 have the maximum frequency in mutation regions. In the frequency of exons individually, exon 47 and exon 50 were the most common in deleted regions and exons 5, 6, and 7 were found most frequently in duplicated regions. CONCLUSIONS: MLPA has better productivity and sensitivity than multiplex PCR. Prenatal diagnosis should be applied in DMD high-risk fetuses to reduce the disease incidence. Furthermore, it is the responsibility of physicians to inform female carriers the importance of prenatal diagnosis.


Assuntos
Distrofia Muscular de Duchenne/genética , China , Distrofina/genética , Éxons/genética , Feminino , Deleção de Genes , Heterozigoto , Humanos , Masculino , Reação em Cadeia da Polimerase Multiplex , Mutação/genética , Gravidez , Deleção de Sequência
15.
Nat Prod Res ; 30(7): 821-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26930107

RESUMO

One new benzopyran derivative (2R(*),4R(*))-3,4-dihydro-5-methoxy-2-methyl-2H-1-benzopyran-4-ol (1), together with five known compounds (2-6), were obtained from the EtOAc extract of the endophytic fungus Penicillium citrinum HL-5126 isolated from the mangrove Brguiera sexangula var. rhynchopetala collected in the South China Sea. Their structures were elucidated by the detailed analysis of comprehensive spectroscopic data. All compounds were evaluated for their antibacterial activities. Compound 6 exhibited potent inhibitory activity against Bacillus subtilis, Bacillus cereus and Micrococcus tetragenus with the same MIC values of 6.94 µM.


Assuntos
Antibacterianos/isolamento & purificação , Benzopiranos/isolamento & purificação , Penicillium/química , Rhizophoraceae/microbiologia , Antibacterianos/química , Benzopiranos/química , China , Estrutura Molecular , Análise Espectral
16.
Steroids ; 94: 7-14, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25528195

RESUMO

Twelve new 9,10-secosteroids designated as subergorgiaols A-L (1-12), along with four known analogues (13-16), were isolated from the gorgonian Subergorgia rubra collected from the South China Sea. Their planar structures and the relative configurations were elucidated by comprehensive spectroscopic methods including NOESY spectra. The absolute configuration of 1 was established by a dimolybdenum tetraacetate [Mo2(AcO)4] induced circular dichroism (ICD) procedure and the modified Mosher's method. Compounds 1-12 represent the first series of 9,10-secosteroids characterized with a hydroxy group at C-8, which are 8-OH derivatives of astrogorgiadiols/calicoferols. Compound 4 exhibited cytotoxicity against the cervical carcinoma cell line (CaSki) with an IC50 value of 2.4 µM, and 6 showed toxicity toward brine shrimp Artemia salina with an LC50 value of 2.0 µM.


Assuntos
Antozoários/química , Secoesteroides/química , Animais , Artemia/efeitos dos fármacos , China , Cromatografia em Gel , Dicroísmo Circular , Dose Letal Mediana , Espectroscopia de Ressonância Magnética , Conformação Molecular , Oceanos e Mares , Secoesteroides/isolamento & purificação , Secoesteroides/farmacologia
17.
ACS Appl Mater Interfaces ; 7(16): 8488-94, 2015 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-25706058

RESUMO

Hierarchical Mn2O3 hollow microspheres of diameter about 6-10 µm were synthesized by solvent-thermal method. When serving as anode materials of LIBs, the hierarchical Mn2O3 hollow microspheres could deliver a reversible capacity of 580 mAh g(-1) at 500 mA g(-1) after 140 cycles, and a specific capacity of 422 mAh g(-1) at a current density as high as 1600 mA g(-1), demonstrating a good rate capability. Ex situ X-ray absorption near edge structure (XANES) spectrum reveals that, for the first time, the pristine Mn2O3 was reduced to metallic Mn when it discharged to 0.01 V, and oxidized to MnO as it charged to 3 V in the first cycle. Furthermore, the XANES data demonstrated also that the average valence of Mn in the sample at charged state has decreased slowly with cycling number, which signifies an incomplete lithiation process and interprets the capacity loss of the Mn2O3 during cycling.

18.
Nat Prod Commun ; 5(8): 1171-4, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20839611

RESUMO

One new cembrane diterpenoid, named sarcolactone A (1), along with five known compounds (2-6) were isolated from the soft coral Sarcophyton infundibuliforme collected from the South China Sea. The structure of sarcolactone A (1) was elucidated by comprehensive analysis of spectral data, especially 2D-NMR spectra (1H-1H COSY, HMBC and NOESY). All the compounds were evaluated for their brine shrimp lethality and antifouling activities.


Assuntos
Antozoários/química , Diterpenos/isolamento & purificação , Animais , Artemia/efeitos dos fármacos , Diterpenos/química , Diterpenos/farmacologia
19.
Int J Cell Biol ; 2010: 289653, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21234375

RESUMO

Human primary fibroblasts are a popular type of somatic cells for the production of induced pluripotent stem (iPS) cells. Here we characterized biological properties of primary fibroblasts in terms of cell-growth rate, cytogenetic stability, and the number of inactive X chromosomes during long-term passaging. We produced eight lines of female human dermal fibroblasts (HDFs) and found normal karyotype and expected pattern of X chromosome inactivation (XCI) at low passages (Passage P1-5). However, four out of the eight HDF lines at high passage numbers (≥ P10) exhibited duplicated hallmarks of inactive X chromosome including two punctuate signals of histone H3 lysine 27 trimethylation (H3K27me3) and X inactive-specific transcript (XIST) RNA signals in approximately 8.5-18.5% of the cells. Our data suggest that the copy number of inactive X chromosomes in a subset of female HDF is increased by a two-fold. Consistently, DNA fluorescent in situ hybridization (FISH) identified 3-4 copies of X chromosomes in one nucleus in this subset of cells with two inactive Xs. We conclude that female HDF cultures exhibit a higher risk of genetic anomalies such as carrying an increased number of X chromosomes including both active and inactive X chromosomes at a high passage (≥ P10).

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