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1.
Materials (Basel) ; 16(9)2023 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-37176454

RESUMO

The self-healing ability of asphalt-aggregate bonding interfaces can maintain the mechanical properties of asphalt mixtures. However, the interface's healing ability will also be affected by moisture and aging. In order to clarify the influence of moisture and aging on the healing ability of a bonding interface, the effects of healing period and temperature on the self-healing level of interfacial strength were measured. The healing master curve of the strength was established. Thereafter, the effects of soaking time, salt solution concentration, and thermal aging on the healing degree of interfacial strength were measured. Based on digital image processing technology and the meso-finite element method, the influence of the interface on the healing performance of the mixture was simulated and analyzed, which was then verified by the beam bend healing test. The results show that the healing index of bonding strength increases with the ascent of healing temperature and period. Healing index gradually decreases with the extension of soaking period, and the higher the concentration of salt in the solution, the worse the healing performance of interfacial strength. After asphalt aging, the healing potential of the interface is weakened. There is a good linear relationship between the healing level of an asphalt-aggregate interface and the level of strength and fracture energy of the mixture. However, the actual healing level of an asphalt mixture is obviously lower than that of the interface, due to the addition of mineral filler. This paper provides a method for predicting the recovery performance of asphalt pavement.

2.
Acta Obstet Gynecol Scand ; 101(11): 1215-1219, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35871773

RESUMO

INTRODUCTION: It is well known that HPA-1a antibodies lead to fetal and neonatal alloimmune thrombocytopenia (FNAIT), and an association with reduced birthweight in boys has been reported. Although it remains unclear whether HLA antibodies cause FNAIT, an association between HLA class I antibodies and reduced birthweight in FNAIT neonates has been observed. The aim of this study was to investigate the incidence of platelet antibodies among Chinese women and the impact of maternal alloimmune antibodies on birthweight among healthy neonates. MATERIAL AND METHODS: In this retrospective observational cohort study, platelet antibody screening was performed among women hospitalized for delivery from March 2019 to November 2020. A portion of each serum sample was used to distinguish HLA class I antibodies from HPA antibodies. Based on neonatal sex, gestational age and maternal age, platelet antibody-negative women who were hospitalized for delivery during the same period were randomly selected as reference groups at a 1:1 ratio for comparisons of the birthweights of healthy neonates delivered by women who were positive or negative for platelet antibodies. RESULTS: Among 15 156 women, 1008 (6.7%) were positive for platelet antibodies; the incidences of positive platelet antibody were 1.2%, 1.9%, 1.6% and 2.0% among women with 1, 2, 3 and >3 pregnancies, respectively. Among 787 platelet antibody-positive serum samples available for further analysis, 548 (69.6%) were positive for HLA class I antibodies bound to platelets, and 239 (30.4%) were positive for HPA antibodies. The average birthweight of healthy neonates delivered by women who were positive for platelet antibodies, HLA class I antibodies or HPA antibodies was 161-483 g lower than that of neonates delivered by women who were negative for these antibodies (P < 0.001). Regarding birthweight reduction, there was no significant difference among women who were positive for these antibodies or between boys and girls (P > 0.05). CONCLUSIONS: This study is the first to report that maternal HPA and HLA class I antibodies are associated with reduced birthweight among healthy neonates delivered by Chinese women. This finding provides information for the study of the effect of maternal alloimmune antibodies on fetal development.


Assuntos
Antígenos de Plaquetas Humanas , Trombocitopenia Neonatal Aloimune , Recém-Nascido , Gravidez , Masculino , Feminino , Humanos , Peso ao Nascer , Estudos Retrospectivos , Anticorpos , Antígenos de Histocompatibilidade Classe I , China
3.
Biochim Biophys Acta ; 1823(8): 1378-88, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22683989

RESUMO

Previously we have shown that interferon (IFN)-α induced apoptosis is predominantly mediated by the upregulation of tumor necrosis factor related apoptosis-inducing ligand (TRAIL) via the caspase-8 pathway. It was also shown that recruitment of mitochondria in IFN-α induced apoptosis involves the cleavage of BH3 interacting domain death agonist (Bid) to truncated Bid (tBid). In the present study, we demonstrate that tBid induced by IFN-α2a activates mitochondrial Bak to trigger the loss of mitochondrial membrane integrity, consequently causing release of apoptosis-inducing factor (AIF) in ovarian cancer cells, OVCAR3. AIF translocates from the mitochondria to the nucleus and induces nuclear fragmentation and cell death. Both a small molecule Bid inhibitor (BI-6C9) or Bid-RNA interference (RNAi) preserved mitochondrial membrane potential, prevented nuclear translocation of AIF, and abrogated IFN-α2a-induced cell death. Cell death induced by tBid was inhibited by AIF-RNAi, indicating that caspase-independent AIF signaling is the main pathway through which Bid mediates cell death. This was further supported by experiments showing that BI-6C9 did not prevent the release of cytochrome c from mitochondria to cytosol, while the release of AIF was prevented. In conclusion, IFN-α2a-induced apoptosis is mediated via the mitochondria-associated pathway involving the cleavage of Bid followed by AIF release that involves Bak activation and translocation of AIF from the mitochondria to the nucleus in OVCAR3 cells.


Assuntos
Fator de Indução de Apoptose/metabolismo , Apoptose , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Interferon-alfa/fisiologia , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/genética , Caspase 9/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Citocromos c/metabolismo , Feminino , Técnicas de Silenciamento de Genes , Humanos , Interferon-alfa/farmacologia , Potencial da Membrana Mitocondrial , Neoplasias Ovarianas , Multimerização Proteica , Transporte Proteico , Interferência de RNA , Proteína X Associada a bcl-2/metabolismo
4.
J Immunother ; 35(1): 23-31, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22130162

RESUMO

Clinical applications of human interferon (IFN)-α have met with varying degrees of success. Nevertheless, key molecules in cell viability regulated by IFN-α have not been clearly identified. Our previous study indicated that IFN (α, ß, and ω) receptor (IFNAR) 1/2- and IFN regulatory factor 9-RNA interference (RNAi) completely restored cell viability after IFN-α treatment in human ovarian adenocarcinoma OVCAR3 cells sensitive to IFN-α. In this study, IFNAR1/2- and IFN regulatory factor 9-RNAi inhibited the gene expression of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), but not of Fas ligand, after IFN-α treatment. In fact, TRAIL but not Fas ligand inhibited the viability of OVCAR3 cells. IFN-α notably upregulated the levels of TRAIL protein in the supernatant and on the membrane of OVCAR3 cells. After TRAIL signaling, caspase 8 inhibitor and BH3 interacting domain death agonist (BID)-RNAi significantly restored cell viability in response to IFN-α and TRAIL in OVCAR3 cells. Furthermore, BID-RNAi prevented both IFN-α and TRAIL from collapsing the mitochondrial membrane potential (ΔΨm). Finally, we provided important evidence that BID overexpression led to significant inhibition of cell viability after IFN-α or TRAIL treatments in human lung carcinoma A549 cells resistant to IFN-α. Thus, this study suggests that BID is crucial for cell viability regulated by IFN-α which can induce mitochondria-mediated apoptosis, indicating a notable potential to be a targeted therapy for IFN-α resistant tumors.


Assuntos
Adenocarcinoma/imunologia , Apoptose , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Neoplasias Ovarianas/imunologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/genética , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/imunologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/genética , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/imunologia , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/metabolismo , Interferon-alfa/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/genética , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , RNA Interferente Pequeno/genética , Receptor de Interferon alfa e beta/genética , Receptor de Interferon alfa e beta/imunologia , Receptor de Interferon alfa e beta/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/genética , Ligante Indutor de Apoptose Relacionado a TNF/imunologia , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Transgenes/genética
5.
J Interferon Cytokine Res ; 31(7): 569-73, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21323569

RESUMO

We have previously reported that low concentrations of interferon (IFN)-activated monocytes exert near-eradicative cytocidal activity against low concentrations of several human tumor cells in vitro. In the present study, we examined 7 human tumor cell lines and 3 diploid lines in the presence or absence of 10 ng/mL IFNα2a and monocytes. The results confirmed strong cytocidal activity against 4 of 7 tumor lines but none against 3 diploid lines. To model larger in vivo tumors, we increased the target cell concentration and determined the concentration of IFNα2a and monocytes, required for cell death. We found that increasing the tumor cell concentration from 10- to 100-fold (10(5) cells/well) required an increase in the concentration of IFNs by over 100-fold and monocytes by 10-fold. High concentrations of monocytes could sometimes kill tumor or diploid cells in the absence of IFN. We may conclude that killing of high concentrations of tumor or diploid cells required high concentrations of monocytes that could sometimes kill in the absence of IFN. Thus, high concentrations of tumor cells required high concentrations of IFN and monocytes to cause near eradication of tumor cells. These findings may have clinical implications.


Assuntos
Interferon-alfa/farmacologia , Monócitos Matadores Ativados/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Linhagem Celular Tumoral , Citotoxicidade Imunológica/efeitos dos fármacos , Cálculos da Dosagem de Medicamento , Humanos , Monócitos Matadores Ativados/imunologia , Monócitos Matadores Ativados/metabolismo , Monócitos Matadores Ativados/patologia , Neoplasias/patologia
6.
J Immunother ; 32(8): 803-16, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19752753

RESUMO

A number of tumors are still resistant to the antiproliferative activity of human interferon (IFN)-alpha. The Janus kinases/Signal Transducers and Activators of Transcription (JAK-STAT) pathway plays an important role in initial IFN signaling. To enhance the antiproliferative activity of IFN-alpha, it is important to elucidate which factors in the JAK-STAT pathway play a key role in eliciting this activity. In human ovarian adenocarcinoma OVCAR3 cells sensitive to both IFN-alpha and IFN-gamma, only IFN regulatory factor 9 (IRF9)-RNA interference (RNAi) completely inhibited the antiproliferative activity of IFN-alpha among the intracellular JAK-STAT pathway factors. Conversely, Stat1-RNAi did not inhibit the antiproliferative activity of IFN-alpha, whereas it partially inhibited that of IFN-gamma. As a cell death pathway, it is reported that tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis through TRAIL-receptor (R) 1 and TRAIL-R2. In IFN-alpha-treated OVCAR3 cells, IRF9-RNAi inhibited transcription of TRAIL whereas Stat1-RNAi did not, suggesting that the transcription of TRAIL induced by IFN-alpha predominantly required IRF9. Furthermore, IFN-stimulated response element-like motifs of TRAIL bound to IFN-stimulated gene factor 3 (ISGF3) complex after IFN-alpha treatment. Subsequently, TRAIL-R2-RNAi inhibited both antiproliferative activities of IFN-alpha and TRAIL, suggesting that TRAIL-R2 mediated both IFN-alpha and TRAIL signals to elicit their antiproliferative activities. Finally, IRF9 overexpression facilitated IFN-alpha-induced apoptosis in T98G (human glioblastoma multiforme) cells, which were resistant to IFN-alpha. Thus, this study suggests that IRF9 is the key factor for eliciting the antiproliferative activity of IFN-alpha and TRAIL may be one of the potential mediators.


Assuntos
Adenocarcinoma/imunologia , Glioblastoma/imunologia , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/metabolismo , Interferon-alfa/farmacologia , Neoplasias Ovarianas/imunologia , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Apoptose/efeitos dos fármacos , Apoptose/genética , Biomarcadores Farmacológicos , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Glioblastoma/patologia , Glioblastoma/terapia , Humanos , Fator Gênico 3 Estimulado por Interferon/metabolismo , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/genética , Interferon gama/farmacologia , Janus Quinases/metabolismo , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/terapia , RNA Interferente Pequeno/genética , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/genética , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/imunologia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo
7.
Int J Hematol ; 88(3): 268-271, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18802675

RESUMO

Although several DNA-based human platelet antigens (HPA) typing techniques, such as PCR-SSP and PCR-SSO, have been established, the typing errors and the lack of interlaboratory reproducibility are still the issues of concerns. In the present study, polymerase chain reaction primers were designed for identification of all the phenotypically different HPA-1 to HPA-17w types by sequencing-based typing (SBT) method using genomic DNA samples. No discrepancies were observed between PCR-SSP typing and SBT typing in typing a panel of HPA-typed platelet donors that included all common HPA types and the rare HPA-1b, 2b, 3b, and 6bw homozygous donors.


Assuntos
Antígenos de Plaquetas Humanas/genética , Doadores Vivos , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA/métodos , Feminino , Humanos , Masculino
8.
Hum Immunol ; 68(10): 854-66, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17961775

RESUMO

HLA phenotypes of 26,266 Chinese individuals who were recruited as potential hematopoietic stem cell donors by the Shanghai Red Cross Marrow Donor Registry, part of the China Marrow Donor Program, were determined for HLA-A, -B, and -DRB1 alleles at low to intermediate resolution using DNA-based typing methods. The large sample size of the study allowed accurate calculation of the Chinese HLA haplotype frequencies. The observed alleles correspond to 19 HLA-A, 44 -B, and 13 -DR split antigens. The serologic equivalents of HLA-A36, -A80, -B78, and -DR18 alleles were not observed. A total of 2,241 distinct HLA-A, -B, -DRB1 haplotypes were identified. Three-locus haplotype frequency was estimated using the maximum likelihood method. The lowest haplotype frequency that can be reliably estimated at a 95% confidence level was 0.000057. Using this cutoff value, 1,220 haplotypes (54%) were statistically reliable and their cumulative haplotype frequency was 0.9730. The cumulative haplotype frequency of the remaining 1,021 haplotypes (46%) was 0.0270. A regression equation of p = 0.192 log N - 0.576 was derived to estimate the probability (p) of finding an HLA-A, -B, -DR split antigens-matched donor in a pool of N Chinese donors.


Assuntos
Medula Óssea/imunologia , Impressões Digitais de DNA , Frequência do Gene , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Antígenos HLA-DR/genética , Povo Asiático/genética , China , Haplótipos , Humanos , Sistema de Registros
9.
Yi Chuan ; 29(2): 177-9, 2007 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-17369172

RESUMO

A total of 1,000 Chinese blood donors were typed for human platelet antigens (HPA) using a sequence specific primers -polymerase chain reaction (PCR-SSP) based HPA genotyping method. An individual with a rare HPA-10w(a+b+) genotype was found. In order to confirm the typing results, a fragment of HPA-10 gene was amplified by PCR and then sequenced. Sequencing data showed that a single G to A substitution at nucleotide 263 occurred, resulting in amino acid change from Arg(CGA) to Gln(CAA) at position 62 of GPa protein. The substitution generated antigenic specificity HPA-10bw. The detection of an HPA-10bw allele in the Chinese population suggests that this rare allele should be considered in platelet alloimmunization, such as neonatal alloimmune thrombocytopenia (NAIT), post-transfusion thrombocytopenic purpura (PTP) and post-transfusion refractoriness to platelets (PTR).


Assuntos
Antígenos de Plaquetas Humanas/genética , Polimorfismo de Nucleotídeo Único , Alelos , Sequência de Bases , China , Genótipo , Humanos , Integrina beta3/genética , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
10.
Retrovirology ; 2: 34, 2005 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-15910683

RESUMO

BACKGROUND: Levels of proviral load in HTLV-1 infected patients correlate with clinical outcome and are reasonably prognostic. Adaptation of proviral load measurement techniques is examined here for use in an experimental rabbit model of HTLV-1 infection. Initial efforts sought to correlate proviral load with route and dose of inoculation and with clinical outcome in this model. These methods contribute to our continuing goal of using the model to test treatments that alleviate virus infection. RESULTS: A real-time PCR assay was used to measure proviral load in blood and tissue samples from a series of rabbits infected using HTLV-1 inocula prepared as either cell-free virus particles, infected cells or blood, or by naked DNA injection. Proviral loads from asymptomatically infected rabbits showed levels corresponding to those reported for human patients with clinically silent HTLV-1 infections. Proviral load was comparably increased in 50% of experimentally infected rabbits that developed either spontaneous benign or malignant tumors while infected. Similarly elevated provirus was found in organs of rabbits with experimentally induced acute leukemia/lymphoma-like disease. Levels of provirus in organs taken at necropsy varied widely suggesting that reservoirs of infections exist in non-lymphoid organs not traditionally thought to be targets for HTLV-1. CONCLUSION: Proviral load measurement is a valuable enhancement to the rabbit model for HTLV-1 infection providing a metric to monitor clinical status of the infected animals as well as a means for the testing of treatment to combat infection. In some cases proviral load in blood did not reflect organ proviral levels, revealing a limitation of this method for monitoring health status of HTLV-1 infected individuals.


Assuntos
Modelos Animais de Doenças , Infecções por HTLV-I/virologia , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Provírus/isolamento & purificação , Carga Viral , Animais , Linhagem Celular , DNA Viral/análise , DNA Viral/sangue , Feminino , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Humanos , Especificidade de Órgãos , Reação em Cadeia da Polimerase , Provírus/genética , Coelhos
11.
Transfusion ; 42(12): 1553-6, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12473133

RESUMO

BACKGROUND: The paucity of appropriate reagents for serologic typing of the Diego blood group has hindered the identification of the rare Di(b-) blood donors needed to transfuse a Dib antigen-negative patient who presented with anti-Dib. Development of an alternative Di typing approach as a supplement to the current serologic typing method is an important and necessary goal. STUDY DESIGN AND METHODS: DI1 and DI2 alleles result from a single C to T substitution at nucleotide 2561 in exon 19 of the human anion exchanger gene causing a proline (DI1) to leucine (DI2) change at amino acid position 854. Allele-specific primers were designed to specifically amplify the DI1 and DI2 alleles using a PCR-based assay system. RESULTS: A PCR sequence-specific primer (SSP) method for Di genotyping was developed, and the specificity and reproducibility of the method were assessed in a blind control study using serologic tests, family segregation, and DNA sequencing analyses. A total of 1,766 DNA samples from unrelated blood donors were typed for DI1 and DI2 alleles and a single Di(b-) donor was identified. The frequency of DI1 and DI2 alleles among Chinese blood donors was 0.0357 and 0.9643, respectively. CONCLUSION: A simple, accurate, and inexpensive DNA-based PCR-SSP method was established for Di genotyping. The typing results can be visualized on a single photograph within 3 hours, making this reliable method suitable for large-scale typing of potential blood donors without serologic backup.


Assuntos
Antígenos de Grupos Sanguíneos/genética , Tipagem e Reações Cruzadas Sanguíneas/métodos , Análise de Sequência de DNA/métodos , Antígenos de Grupos Sanguíneos/análise , Tipagem e Reações Cruzadas Sanguíneas/normas , Transfusão de Sangue/métodos , Primers do DNA , Saúde da Família , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Mieloma Múltiplo/terapia , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Análise de Sequência de DNA/normas
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