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1.
ACS Appl Mater Interfaces ; 16(14): 17673-17682, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38533740

RESUMO

Passivation of the magnesium (Mg) anode in the chloride-free electrolytes using commercially available Mg salts is a critical issue for rechargeable Mg batteries. Herein, a high donor number cosolvent of 1-methylimidazolium (MeIm) is introduced into Mg(TFSI)2- and Mg(HMDS)2-based electrolytes to address the passivation problem and realize highly reversible Mg plating/stripping. Theoretical calculations and experimental characterization results reveal that the strong coordination ability of MeIm with Mg2+ can weaken the anion-cation interactions and promote the formation of free anions that have higher reduction stability, thus significantly suppressing anion-derived passivation layer formation. By adding MeIm cosolvent into Mg(TFSI)2-based electrolyte, the average Coulombic efficiency of the Mg//Cu cell is increased from less than 20% to over 90%, and the Mg//Mg cell can stably cycle for over 800 h with a low overpotential. In the MeIm-regulated Mg(HMDS)2-based electrolyte, the solvation structure change, featured by an effective separation of Mg2+ and HMDS-, greatly increases the ionic conductivity by more than 30 times. This solvation structure regulation strategy for noncorrosive electrolytes of commercially available Mg salts has a great potential for application in future rechargeable Mg metal batteries.

3.
Reproduction ; 166(4): 247-261, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37561570

RESUMO

In brief: The regulatory role of BMP15 on porcine ovarian follicular development still remains unclear. This study reveals that biallelic editing of BMP15 impairs SMAD signaling and inhibits granulosa cell proliferation, resulting in porcine follicular development arrest and ovarian hypoplasia. Abstract: Bone morphogenetic protein 15 (BMP15) is a member of the transforming growth factor beta (TGF-ß) superfamily, which is critical for facilitating ovarian folliculogenesis in mono-ovulatory mammalian species but is not essential in polyovulatory mice. Our previously established BMP15-edited pigs presented varied female reproductive phenotypes, suggesting the important role of BMP15 in ovarian folliculogenesis in polyovulatory pigs. To understand the regulatory mechanism underlying the effect of BMP15 on porcine ovarian follicular development, we molecularly characterized infertile biallelic-BMP15-edited gilts with ovarian hypoplasia. We found that an absence of BMP15 proteins in biallelic-BMP15-edited gilts can lead to premature activation of primordial follicles, possibly through the upregulation of KITLG-KIT-PI3K-AKT signaling pathways. However, this absence severely impaired SMAD (Sma and Mad proteins from Caenorhabditis elegans and Drosophila, respectively) signaling, causing severely reduced granulosa cell proliferation, leading to the arrest of follicular development during the preantral stage and ovarian hypoplasia, resulting in complete infertility. Our study expands the understanding of the molecular functions of BMP15 in nonrodent polyovulatory mammals.


Assuntos
Proteína Morfogenética Óssea 15 , Fosfatidilinositol 3-Quinases , Feminino , Suínos , Animais , Camundongos , Proteína Morfogenética Óssea 15/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Folículo Ovariano/metabolismo , Ovário/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fator 9 de Diferenciação de Crescimento/genética , Mamíferos/metabolismo
4.
Nanomaterials (Basel) ; 13(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36677981

RESUMO

The synthesis of bimetallic iron-nickel nanoparticles with control over the synthesized phases, particle size, surface chemistry, and oxidation level remains a challenge that limits the application of these nanoparticles. Pulsed laser ablation in liquid allows the properties tuning of the generated nanoparticles by changing the ablation solvent. Organic solvents such as acetone can minimize nanoparticle oxidation. Yet, economical laboratory and technical grade solvents that allow cost-effective production of FeNi nanoparticles contain water impurities, which are a potential source of oxidation. Here, we investigated the influence of water impurities in acetone on the properties of FeNi nanoparticles generated by pulsed laser ablation in liquids. To remove water impurities and produce "dried acetone", cost-effective and reusable molecular sieves (3 Å) are employed. The results show that the Fe50Ni50 nanoparticles' properties are influenced by the water content of the solvent. The metastable HCP FeNi phase is found in NPs prepared in acetone, while only the FCC phase is observed in NPs formed in water. Mössbauer spectroscopy revealed that the FeNi nanoparticles oxidation in dried acetone is reduced by 8% compared to acetone. The high-field magnetization of Fe50Ni50 nanoparticles in water is the highest, 68 Am2/kg, followed by the nanoparticles obtained after ablation in acetone without water impurities, 59 Am2/kg, and acetone, 52 Am2/kg. The core-shell structures formed in these three liquids are also distinctive, demonstrating that a core-shell structure with an outer oxide layer is formed in water, while carbon external layers are obtained in acetone without water impurity. The results confirm that the size, structure, phase, and oxidation of FeNi nanoparticles produced by pulsed laser ablation in liquids can be modified by changing the solvent or just reducing the water impurities in the organic solvent.

5.
Adv Mater ; 34(30): e2203783, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35657273

RESUMO

Passivation of the Mg anode surface in conventional electrolytes constitutes a critical issue for practical Mg batteries. In this work, a perfluorinated tert-butoxide magnesium salt, Mg(pftb)2 , is codissolved with MgCl2 in tetrahydrofuran (THF) to form an all-magnesium salt electrolyte. Raman spectroscopy and density function theory calculation confirm that [Mg2 Cl3 ·6THF]+ [Mg(pftb)3 ]- is the main electrochemically active species of the electrolyte. The proper lowest unoccupied molecular orbital energy level of the [Mg(pftb)3 ]- anion enables in situ formation of a stable solid electrolyte interphase (SEI) on Mg anodes. A detailed analysis of the SEI reveals that its stability originates from a dual-layered organic/inorganic hybrid structure. Mg//Cu and Mg//Mg cells using the electrolyte achieve a high Coulombic efficiency of 99.7% over 3000 cycles, and low overpotentials over ultralong-cycle lives of 8100, 3000, and 1500 h at current densities of 0.5, 1.0, and 2.0 mA cm-2 , respectively. The robust SEI layer, once formed on a Mg electrode, is also shown highly effective in suppressing side-reactions in a TFSI- -containing electrolyte. A high Coulombic efficiency of 99.5% over 800 cycles is also demonstrated for a Mg//Mo6 S8 full cell, showing great promise of the SEI forming electrolyte in future Mg batteries.

6.
J Affect Disord ; 303: 148-154, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35157948

RESUMO

BACKGROUND: Childhood maltreatment is significantly associated with greater occurrence of mental disorders in adulthood such as depression and anxiety. As a key node of the limbic system, the amygdala is engaged in emotional processing and regulation and is dysfunctional in many psychiatric disorders. The present study aimed at exploring the association between childhood maltreatment and amygdala-based functional networks and their potential contributions to depression and anxiety. METHODS: Totally 90 Chinese healthy volunteers participated in a resting-state fMRI experiment. Levels of childhood maltreatment experience were assessed using the Childhood Trauma Questionnaire (CTQ-SF) as well as levels of depression and anxiety. Associations between CTQ-SF scores and bilateral amygdala gray matter volume and resting-state functional connectivity (RSFC) of the amygdala and selected regions of interest were analyzed using multiple regression analyses with sex and age as covariates. A subsequent moderation analysis was performed to identify whether associations were predictive of depression and anxiety levels. RESULTS: Childhood maltreatment was significantly negatively associated with RSFC between left amygdala and anterior insula. Further sub-region analyses revealed that this negative association only occurred for the left centromedial amygdala subregion, which subsequently moderated the relationship between levels of childhood emotional abuse and depression / anxiety. LIMITATIONS: No psychiatric patients were involved and specific neural associations with different childhood maltreatment subtypes need to be examined in future studies. CONCLUSION: The present findings provide evidence for altered RSFC of centromedial amygdala and the anterior insula associated with childhood maltreatment and which moderate levels of depression and anxiety in adulthood.


Assuntos
Depressão , Abuso Emocional , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Ansiedade/diagnóstico por imagem , Transtornos de Ansiedade/diagnóstico por imagem , Depressão/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética
7.
Small Methods ; 5(12): e2100976, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34928039

RESUMO

Investigation of the mechanism of the water oxidation reaction for hematite photoanodes has been one of the most persistently pursued topics in the course of understanding photoelectrochemical water splitting by transition metal oxides. Unfortunately, existing experimental techniques often require over-simplified models and theories that assume only one reaction path. In this work, however, it is proposed that water oxidation on hematite can proceed via mixed reaction paths according to spectroelectrochemical results without a priori assumptions. The true absorption signals of surface states responsible for water oxidation are isolated from subsidiary signals for undoped and Ti-doped hematite and contrasted with those of inactive species. The evolution of absorption signals as a function of applied potential and illumination intensity highlights the non-negligible contribution of direct hole transfer, especially for highly doped hematite.

8.
Small ; 16(39): e2003112, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32885599

RESUMO

Gallium arsenide (GaAs) provides a suitable bandgap (1.43 eV) for solar spectrum absorption and allows a larger photovoltage compared to silicon, suggesting great potential as a photoanode toward water splitting. Photocorrosion under water oxidation condition, however, leads to decomposition or the formation of an insulating oxide layer, which limits the photoelectrochemical performance and stability of GaAs. In this work, a self-limiting electrodeposition method of Ni on GaAs is reported to either generate ultra-thin continuous film or nanoislands with high particle density by controlling deposition time. The self-limiting growth mechanism is validated by potential transients, X-ray photoelectron spectroscopy composition and depth profile measurements. This deposition method exhibits a rapid nucleation, forms an initial metallic layer followed by a hydroxide/oxyhydroxide nanofilm on the GaAs surface and is independent of layer thickness versus deposition time when coalescence is reached. A photocurrent up to 8.9 mA cm-2 with a photovoltage of 0.11 V is obtained for continuous ultrathin films, while a photocurrent density of 9.2 mA cm-2 with a photovoltage of 0.50 V is reached for the discontinuous nanoislands layers in an aqueous solution containing the reversible redox couple K3 Fe(CN)6 /K4 Fe(CN)6 .

9.
Mol Genet Genomic Med ; 8(10): e1470, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32840018

RESUMO

BACKGROUND: Fertilization failure (FF) is a complex reproductive disorder characterized by the failure of pronuclei formation during fertilization. In addition to some cases caused by iatrogenic problems and known genetic factors, there are still many unexplained aspects of FF. Here, we aimed to assess the clinical and genetic characteristics of two families experiencing primary infertility with FF. METHODS: We have characterized two families from China. All of the infertile couples presented with similar clinical phenotypes, that is, partial or total fertilization failure in repeated cycles. We performed Sanger sequencing of their WEE2, TLE6, and PLCZ1 genes, and further bioinformatics and functional analyses were performed to identify the pathogenic elements of the variants. RESULTS: We identified novel compound heterozygous mutations c.1259C>T (p.P420L) and c.1733T>C (p.M578T) in the PLCZ1 gene in a male patient of family 1 with total fertilization failure, and another novel homozygous mutation c.1727T>C (p.L576P) in the same gene in a male patient of family 2 with partial fertilization failure. These three novel mutations were absent in the control cohort and in the databases. The amino acids were conserved at their positions among six different species. All mutant amino acids were located in key domains and were predicted to impair hydrolytic activity and lead to PLCZ1 dysfunction. Further functional detection revealed that the three mutations could significantly impair the catalytic activity of PLCZ1. CONCLUSIONS: We identified three novel mutations in PLCZ1 associated with partial and total fertilization failure and have provided new evidence about the genetic basis of FF.


Assuntos
Infertilidade/genética , Fosfoinositídeo Fosfolipase C/genética , Adulto , Domínio Catalítico , Proteínas de Ciclo Celular/genética , Proteínas Correpressoras/genética , Células HEK293 , Humanos , Infertilidade/patologia , Mutação com Perda de Função , Masculino , Fosfoinositídeo Fosfolipase C/química , Fosfoinositídeo Fosfolipase C/metabolismo , Proteínas Tirosina Quinases/genética
10.
Biol Reprod ; 103(5): 1054-1068, 2020 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-32761111

RESUMO

Bone morphogenetic protein 15 (BMP15), a member of the transforming growth factor beta superfamily, plays an essential role in ovarian follicular development in mono-ovulatory mammalian species. Studies using a biallelic knockout mouse model revealed that BMP15 potentially has just a minimal impact on female fertility and ovarian follicular development in polyovulatory species. In contrast, our previous study demonstrated that in vivo knockdown of BMP15 significantly affected porcine female fertility, as evidenced by the dysplastic ovaries containing significantly decreased numbers of follicles and an increased number of abnormal follicles. This finding implied that BMP15 plays an important role in the regulation of female fertility and ovarian follicular development in polyovulatory species. To further investigate the regulatory role of BMP15 in porcine ovarian and follicular development, here, we describe the efficient generation of BMP15-edited Yorkshire pigs using CRISPR/Cas9. Using artificial insemination experiments, we found that the biallelically edited gilts were all infertile, regardless of different genotypes. One monoallelically edited gilt #4 (Δ66 bp/WT) was fertile and could deliver offspring with a litter size comparable to that of wild-type gilts. Further analysis established that the infertility of biallelically edited gilts was caused by the arrest of follicular development at preantral stages, with formation of numerous structurally abnormal follicles, resulting in streaky ovaries and the absence of obvious estrous cycles. Our results strongly suggest that the role of BMP15 in nonrodent polyovulatory species may be as important as that in mono-ovulatory species.


Assuntos
Proteína Morfogenética Óssea 15/genética , Fertilidade/genética , Oócitos/metabolismo , Folículo Ovariano/metabolismo , Ovário/metabolismo , Animais , Proteína Morfogenética Óssea 15/metabolismo , Sistemas CRISPR-Cas , Feminino , Suínos
11.
J Exp Child Psychol ; 198: 104908, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32600740

RESUMO

The baby schema effect induced by particular features of baby faces acts as an innate releasing mechanism that evokes positive emotions and instinctual behavioral responses. Our prior research in adults has revealed that this effect initially found in infancy extends into child faces. Adolescence is an important period involving development in various aspects of cognition, including face perception. Here, we investigated whether the extended baby schema effect we previously found in adult observers develops earlier-in adolescence-and how different it appears in adolescents as compared with in adults. In the current study, 76 adolescents and 77 adults were asked to judge the likeability of 148 neutral faces of infants and children (0.08-6.5 years of age) on 7-point scales. Results showed that both adolescents and adults perceived the faces of both infants and children younger than 4.6 years as more likeable relative to those of older children, indicating that the baby schema effect previously found in adulthood also occurs in adolescence. However, adolescents rated lower than adults toward the infant and child faces across all face ages, suggesting that this effect might be under development in adolescence. Overall, our findings provide new evidence for the development of face perception in adolescence and demonstrate age-related changes in innate releasing mechanisms in our protective and caretaking responses toward infants and children.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Reconhecimento Facial/fisiologia , Percepção Social , Adolescente , Adulto , Feminino , Humanos , Masculino
12.
Reprod Fertil Dev ; 32(11): 999-1011, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32693912

RESUMO

Bone morphogenetic protein 15 (BMP15) is a member of the transforming growth factor-ß (TGFB) superfamily that plays an essential role in mammalian ovary development, oocyte maturation and litter size. However, little is known regarding the expression pattern and biological function of BMP15 in male gonads. In this study we established, for the first time, a transgenic pig model with BMP15 constitutively knocked down by short hairpin (sh) RNA. The transgenic boars were fertile, but sperm viability was decreased. Further analysis of the TGFB/SMAD pathway and markers of reproductive capacity, namely androgen receptor and protamine 2, failed to identify any differentially expressed genes. These results indicate that, in the pig, the biological function of BMP15 in the development of male gonads is not as crucial as in ovary development. However, the role of BMP15 in sperm viability requires further investigation. This study provides new insights into the role of BMP15 in male pig reproduction.


Assuntos
Proteína Morfogenética Óssea 15/genética , Espermatogênese/genética , Espermatozoides/metabolismo , Testículo/metabolismo , Animais , Proteína Morfogenética Óssea 15/metabolismo , Técnicas de Silenciamento de Genes , Masculino , Análise do Sêmen , Transdução de Sinais/genética , Proteínas Smad/metabolismo , Espermatozoides/citologia , Suínos , Testículo/citologia , Fator de Crescimento Transformador beta1/metabolismo
13.
Nanomaterials (Basel) ; 9(6)2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31163676

RESUMO

Polarization Manipulation has been widely used and plays a key role in wave propagation and information processing. Here, we introduce a polarization rotator in the terahertz range with a polarization conversion ratio up to 99.98% at 4.51 terahertz. It has a single graphene layer on top of the structure patterned by 45° tilted space elliptical rings. By changing the Fermi level from 0.3 ev to 0.7 ev of the graphene, we can turn the reflective light polarization direction between 0° to 90°withnearly unique magnitude. Surface currents theories and graphene characteristics clarify the relationship between polarization angle and Fermi level to be a sine equation adjusted voltage. We firstly put forward an equation to thetunable graphene changing the reflective light polarization angle. It can be widely used in measurement, optic communication, and biology. Besides, with nearly the unique reflective light in different directions, the rotator is designed into a novel radially polarization converter. The latter can be switched from radially polarized light to linearly polarized light, and vice versa, in the terahertz region.

14.
ChemSusChem ; 12(1): 231-239, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30412343

RESUMO

The electrochemical reduction of CO2 provides an alternative carbon-neutral path for renewable synthesis of fuels and value-added chemicals. This work demonstrates that dendritic, bimetallic Cu-Bi electrocatalysts with nanometer-sized grains are capable of formate generation with a high selectivity. Optimizing composition of electrocatalyst could achieve a faradic efficiency of 90 % at -0.8 to -0.9 VRHE , and a partial current of more than 2 mA cm-2 . The combination of Cu with Bi enables modulation of the adsorption strength of intermediates. This leads to an increased selectivity and suppressed formation of spurious species, especially hydrogen and CO. Comparison of product distribution for Cu-In versus Cu-Bi indicated that Bi is essential to induce a favorable adsorption configuration of the intermediate species and to promote formate production.

15.
RSC Adv ; 9(48): 28248-28252, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-35530481

RESUMO

A simple, rapid, sensitive, selective and label-free method is presented for the colorimetric determination of lincomycin (Lin) by using HAuCl4 and NaOH. Upon the addition of Lin, the mixture of HAuCl4 and NaOH shows a color change from colorless to blue (or dark blue). The limit of colorimetric detection is as low as 1 µM, observed both in Milli-Q water and real samples. The selectivity of Lin detection is excellent compared with 9 other common antibiotics. On the basis of the "three-color" principle of Thomas Young, we extracted the red, green and blue (RGB) alterations of the sensor in the absence and presence of different concentrations of Lin. The color changes are quantitatively illustrated by the total Euclidean distances (EDs = [ΔR2 + ΔG2 + ΔB2]1/2). The good linear relationship between the EDs and Lin concentration is used for the quantitative assay of Lin. The developed method demonstrates great potential for the detection of Lin in environmental water and milk.

16.
World J Gastroenterol ; 13(27): 3752-5, 2007 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-17659739

RESUMO

AIM: To evaluate the safety of donors in adult living donor liver transplantation (LDLT) using the right lobe in a single liver transplantation center in China. METHODS: We investigated retrospectively 52 living donor liver resections performed from October 2003 to July 2006. All patients were evaluated by blood tests and abdominal CT. The mean donor age was 28.2 +/- 7.4 years. Residual liver volume was 42.1% +/- 4.7%. Mean operative time was 420 +/- 76.2 min; mean ICU stay, less than 36 h; mean hospital stay, 16.4 +/- 8.6 d; and mean follow-up period, 6 mo. RESULTS: There was no mortality. The overall complication rate was 40% (21 donors). Major complications included biliary leak in two, and pneumonia in 2 donors. Minor complications included mild pleural effusion in 12 donors, transient ascites in 6, mild depression in 4, intra-abdominal collections in 2, and wound infections in 1 donor. Residual liver volume did not affect the complication rate. None required re-operation. Return to pre-donation activity occurred within 5-8 wk. CONCLUSION: Right hemi-hepatectomy can be performed safely with minimal risk in cases of careful donor selection. Major complications occurred in only 7.7% of our series.


Assuntos
Hepatectomia/efeitos adversos , Transplante de Fígado , Fígado/cirurgia , Doadores Vivos , Adolescente , Adulto , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , China/epidemiologia , Seleção do Doador , Feminino , Seguimentos , Hepatectomia/métodos , Humanos , Tempo de Internação , Fígado/diagnóstico por imagem , Fígado/enzimologia , Transplante de Fígado/estatística & dados numéricos , Doadores Vivos/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Fatores de Tempo , Tomografia Computadorizada por Raios X
17.
Zhonghua Gan Zang Bing Za Zhi ; 12(6): 331-3, 2004 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-15225422

RESUMO

OBJECTIVE: To investigate the alteration of HBV markers in liver allograft of HBV related recipients pre and post liver transplantation under Lamivudine or combination of Lamivudine with HBIG prophylaxis and explore the mechanism of HBV de nova infection in liver allograft after orthotopic liver transplantation, as well as seek to establish a optimal prophylactic protocol. METHODS: The serial liver biopsy specimens of 90 liver allograft and sera of 78 liver transplant recipients during operation and after 1 week, 1 month, 3 months, 6 months, 12 months, 24 months post transplantation have been collected and detected for HBV markers with enzyme-linked radioimmunoassay, fluorescent quantitative assay for HBV-DNA in serology and with immunohistochemistry stain, HBV-DNA in situ hybridization in histology for detection of HBV markers in liver allograft samples. RESULTS: Whether recipients with active replicative or inactive replicative HBV preoperatively, none of positive HBV-DNA, HBsAg and HBcAg in 100% liver biopsy specimens with HBV-DNA hybridization in situ and immunohistochemistry stains in histology within 2 hours after reperfusion. CONCLUSION: Whatever HBV replicative status the recipients have before surgery, no evidence of HBV particles direct invasion to the liver allograft from HBV related cirrhotics during operation under current prophylactic measures. However, the further supposed mechanism and its significance in HBV de nova infection of liver allograft remained to be disclosed further.


Assuntos
Antígenos da Hepatite B/sangue , Vírus da Hepatite B/crescimento & desenvolvimento , Hepatite B Crônica/cirurgia , Transplante de Fígado , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Criança , DNA Viral/sangue , Feminino , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/genética , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/tratamento farmacológico , Humanos , Imunização Passiva , Imunoglobulinas/administração & dosagem , Lamivudina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios/métodos , Prevenção Secundária
18.
Zhonghua Gan Zang Bing Za Zhi ; 12(2): 85-7, 2004 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-14980107

RESUMO

OBJECTIVES: To investigate the reversal effect of gene MDR1 and MRP with combinational antisense phosphorothioate oligonucleotide on Drug-resistant human hepatocellular carcinoma cells SMMC-7721/ADM. METHODS: SMMC-7721/ADM was transfected with synthetic antisense phosphorothioate oligonucleotides complementary to gene MDR1 and MRP mediated by Lipofectamine. Drug sensitivity was measured by MTT assay, Fluorescence intensity of cells was determined by flow cytometric analysis, RH123 and DNR retention was assayed by confocal scanning laser microscopy. RESULTS: ASODN of MDR1+MRP increased the sensitivity of SMMC-7721/ADM to chemotherapeutic drug more significantly than that any of MDR1 and MRP did separately. But they did not enhance the inhibition expression of protein of p190 or p170. CONCLUSION: Drug-resistance could be reversed significantly when antisense phosphorothioate oligonucleotide of MDR1+MRP were transfected into drug-resistant human hepatocellular carcinoma cells SMMC-7721/ADM together.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Genes MDR , Neoplasias Hepáticas/tratamento farmacológico , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Oligonucleotídeos Antissenso/farmacologia , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Daunorrubicina/metabolismo , Daunorrubicina/farmacologia , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Humanos , Neoplasias Hepáticas/genética , Rodamina 123/metabolismo
19.
Hepatobiliary Pancreat Dis Int ; 2(1): 44-7, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14599928

RESUMO

BACKGROUND: To evaluate feasibility and safety of venovenous bypass prior to mobilization of the liver during orthotopic liver transplantation (OLT). METHODS: Fifty-four patients were classified into two groups. Group A consisted of 23 patients receiving OLT with classical venovenous bypass. Group B consisted of 31 patients who received a modified-procedure: venovenous bypass ahead of the mobilization of the liver during OLT. The blood loss, duration of venovenous bypass, cold ischemia time, anhepatic phase, and transfusion during operation in the two groups were compared. Complications after the operation were also compared between the two groups. RESULTS: The duration of venovenous bypass and cold ischemia time in group A were longer than those in group B [(99.78+/-21.36 min) vs (96.32+/-22.25 min) and (484.78+/-134.01 min) vs (443.15+/- 85.27 min)]. The anhepatic phase lasted for about 100 min averagely in the two groups. The volumes of blood loss and transfusion during the operation were larger in group A than in group B [(5096+/-4243 ml) vs (1726+/-1125 ml) and (3676+/-2938.74 ml) vs (1217.69+/-829.72 ml)]. Postoperative complications occurred in 26 patients of group A and in 19 patients of group B. CONCLUSION: This modified-procedure or venovenous bypass ahead of mobilization of the liver in OLT can reduce the blood loss during OLT and the incidence of postoperative complications without prolongation of the anhepatic phase and duration of venovenous bypass.


Assuntos
Transplante de Fígado/métodos , Complicações Pós-Operatórias/etiologia , Procedimentos Cirúrgicos Vasculares/métodos , Adolescente , Adulto , Idoso , Perda Sanguínea Cirúrgica/prevenção & controle , Criança , Feminino , Humanos , Transplante de Fígado/efeitos adversos , Masculino , Pessoa de Meia-Idade
20.
Hepatobiliary Pancreat Dis Int ; 2(2): 196-201, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-14599968

RESUMO

OBJECTIVE: To investigate the dynamic alternations of HBV markers of active HBV replication recipients receiving lamivudine prophylaxis after liver transplantation. METHODS: Serial liver biopsy samples and sera were obtained from 15 recipients and examined with enzyme-linked radioimmunoassay for HBsAg, HBeAg, HBsAb, HBcAb and HBeAb, and fluorescent quantitative assay for quantitation of HBV DNA in serum. Immunohistochemical staining of HBsAg, HBcAg and HBV DNA hybridization in situ were used to detect HBV markers in liver biopsy samples. RESULTS: 100 mg lamivudine taken orally every day for 2 weeks before transplantation enabled 12 (80%) of 15 active viral replication recipients (HBV DNA positive) to converse to HBV DNA negative. HBsAb, HBcAb and HBeAb in serum emerged in 1-2 weeks after liver transplantation, and disappeared gradually within 6 months; HBV DNA fluorescent quantitative assay showed constant negativity in serum. Immunohistochemical staining of HBsAg, HBcAg and HBV DNA hybridization in situ in liver biopsy samples showed negative results synchorously. Eight of the 15 HBV active replication recipients lost HBV markers thoroughly both in serology and tissue staining as well as HBV DNA hybridization in situ of serial liver biopsy samples from 12 to 44 weeks after liver transplantation. Should any of HBsAg, HBeAg in serology and HBsAg, HBcAg in immunohistochemical staining was positive, or HBV DNA detectable in serum, or HBV DNA hybridization in situ in liver tissue positive, allograft HBV reinfection or De novo liver allograft infection could be diagnosed. Furthermore, if associated with elevation of ALT and bilirubin, the diagnosis of HBV hepatitis recurrence could be established. CONCLUSION: Allograft HBV reinfection or De novo liver allograft infection in active viral replication recipients could be prevented with lamivudine regimen, and further clearance of HBV may be possible if proper measures are taken.


Assuntos
Vírus da Hepatite B/crescimento & desenvolvimento , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/cirurgia , Transplante de Fígado , Inibidores da Transcriptase Reversa/uso terapêutico , Adulto , Idoso , Biomarcadores , DNA Viral/sangue , Feminino , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Humanos , Lamivudina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/virologia , Estudos Prospectivos , Recidiva , Replicação Viral
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