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1.
J Dairy Sci ; 104(3): 2924-2934, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33455765

RESUMO

We evaluated the effects of propylene glycol (PG) on in vitro ruminal fermentation, methanogenesis, and microbial community structure. A completely randomized design was conducted in the in vitro incubation, and 4 culture PG dose levels (0, 7.5, 15, and 22.5 µL/g of dry matter) were used in the trial. Based on the fermentation results, the control group (0 µL/g of dry matter, CON) and the second treatment group (15.0 µL/g of dry matter, TRT) were chosen for further analysis to explore the effects of PG on the bacterial and archaeal community structure. The concentrations of propanol, propanal, and succinate increased linearly, whereas the concentration of l-lactate decreased linearly as PG doses increased. The molar proportion of propionate demonstrated a linear increase with increasing PG doses. In contrast with propionate, the molar proportion of acetate and butyrate, and acetate-to-propionate ratio decreased linearly with increasing PG doses. The addition of PG markedly decreased methane production without negative effects on nutrient degradability. In the archaeal level, the relative abundance of Methanobrevibacter tended to decrease, but that of Methanomassiliicoccus significantly increased in TRT group. At the bacterial level, the relative abundance of Bacteroidetes and Prevotella in TRT group was numerically higher than that in CON group. The analysis of the Negativicutes class showed that the relative abundance of Succiniclasticum tended to increase, whereas that of Selenomonas tended to decrease in TRT group. These results demonstrated that PG might be used as an inhibitor to mitigate methane emission. However, the small decrease in methane production will limit the application of PG as a methane inhibitor in production practices. Further research is needed to determine whether use together with other inhibitors may improve the effects of PG on the utilization of reducing equivalents ([H]) and methane production.


Assuntos
Microbiota , Rúmen , Ração Animal/análise , Animais , Dieta , Digestão , Feminino , Fermentação , Lactação , Metano/metabolismo , Rúmen/metabolismo
2.
Zhonghua Gan Zang Bing Za Zhi ; 28(5): 397-402, 2020 May 20.
Artigo em Chinês | MEDLINE | ID: mdl-32536055

RESUMO

Objective: To investigate the incidence rate, influencing factors and prognosis of infection-induced acute renal injury (AKI) in patients with acute-on-chronic liver failure (ACLF). Methods: 516 cases with acute-on-chronic liver failure complicated with infection that were hospitalized in our hospital during 2014 to 2016 were retrospectively studied. General conditions and clinical characteristics of the patients were collected, and grouped according to the presence or absence of incidence and severity of AKI. General conditions, laboratory results, occurrence of complications and survival were compared and analyzed. Results: The main causes were HBV infection (67.8%) and alcoholic liver disease (20.0%). The most common sites of infection were abdominal cavity, lung and blood. Multivariate analysis showed that neutrophil count, TBIL, lactate and septic shock were independent risk factors for infection-induced AKI in ACLF patients. The cumulative mortality in patients with AKI after infection at 28, 90 and 360 days was significantly higher than those without AKI (51.6% and 20.5%, 70.2% and 40.3%, 73.4% and 45.9%; P < 0.01). In both groups, deaths had occurred mainly in the early (0 ~ 28 d) and middle (29 ~ 90 d) stage of follow-up period. In the late follow-up period (91-360 d), there was no statistically significant difference in mortality rate between the two groups. Conclusion: Infection is an important inducing cause of AKI in ACLF patients. The underlying liver disease and the severity of infection are significantly related to the infection-induced AKI in ACLF patients, and once AKI occurs after infection, the mortality rate of the patients is significantly increased.


Assuntos
Injúria Renal Aguda , Insuficiência Hepática Crônica Agudizada , Infecções , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Insuficiência Hepática Crônica Agudizada/etiologia , Humanos , Incidência , Infecções/complicações , Prognóstico , Estudos Retrospectivos , Fatores de Risco
3.
Fa Yi Xue Za Zhi ; 35(1): 63-67, 2019 Feb.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-30896122

RESUMO

OBJECTIVES: To investigate the genetic polymorphisms of 17 STR loci in Uygur population of Akesu in Xinjiang Uygur Autonomous Region. METHODS: Blood samples from 10 094 unrelated individuals of Uygur population of Akesu in Xinjiang were amplified by using the 17+1 PCR amplification kit, and 17 STR loci typing were detected. Allele distribution and population genetic parameters of each locus were calculated, and compared with those of Chinese Han population, and Uygur population of Yili, Hotan and Turpan regions. RESULTS: In the 10 094 unrelated Uygur individuals, 252 alleles were detected. All loci meet the Hardy-Weinberg equilibrium using a chi-square goodness-of-fit test expectation except vWA loci. Fourteen out of the 17 STR loci, including D13S317, showed high power of discrimination. A significant difference on the allele distribution of all the 17 STR loci was observed between Uygur population of Akesu and Chinese Han population, and the difference of some loci existed between Uygur population of Akesu and the other three Uygur populations. CONCLUSIONS: The 17 STR loci are highly polymorphic genetic markers, and the polymorphic information could serve as reference data for forensic individual identification and paternity identification in Akesu.


Assuntos
Povo Asiático , Genética Populacional , Repetições de Microssatélites , Povo Asiático/genética , China , Etnicidade , Frequência do Gene , Humanos , Polimorfismo Genético
4.
J Dairy Sci ; 101(3): 2579-2587, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29331457

RESUMO

The objective of this study was to determine whether the responsiveness of the mammary gland to prolactin (PRL) is affected by the concentration of the hormone. After 1 pre-experimental week (d -7 to -1), 18 Holstein cows in mid to late lactation were injected intramuscularly twice daily with either 0.5 mg of quinagolide (QN) or 2 mL of water (control) for 2 wk (d 1 to 14; treatment period). After the treatment period, all cows received daily subcutaneous injections of 300 mg of domperidone (DOMP) for 3 wk (d 15 to 35; DOMP period). The cows were monitored for an additional 2 wk as a posttreatment period (d 36 to 49). Blood and milk samples were collected 3 times per week. Additionally, blood samples were collected during the a.m. milking on d -4, 14, and 35. Milk production was not affected by QN during the treatment period but was increased during the DOMP and posttreatment periods in the QN cows. With respect to milk composition, the treatments affected only the protein content, which was greater in the QN cows during the treatment period. Blood PRL concentration declined during QN injections and was lower in the QN cows than in the control cows between d 5 and 14. The basal concentration of PRL was increased by DOMP injections during the DOMP and posttreatment periods but was not affected by previous QN injections. Prolactin concentration in milk was not affected by the QN treatments but was increased by DOMP injections during the DOMP and posttreatment periods. Milking-induced PRL release was decreased by QN on d 14. On d 35, milking did not induce a significant release of PRL above the baseline for both treatments. In conclusion, the results of this experiment support the contention that the mammary gland's responsiveness to PRL is modulated by the previous level of the hormone.


Assuntos
Bovinos/fisiologia , Leite/metabolismo , Prolactina/metabolismo , Aminoquinolinas , Animais , Domperidona/administração & dosagem , Agonistas de Dopamina , Antagonistas de Dopamina/administração & dosagem , Feminino , Injeções Intramusculares/veterinária , Injeções Subcutâneas/veterinária , Lactação , Leite/química , Prolactina/sangue
5.
J Dairy Sci ; 101(3): 2588-2601, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29274969

RESUMO

Estradiol inhibits milk production in dairy cows. The present study evaluated the effect of 17ß-estradiol (E2) injections on prolactin (PRL) secretion and the mammary gland response to this hormone. Eight mid-lactation cows were used in a crossover design. During each experimental period, the cows were injected daily with either E2 (2.5 mg) or soy oil (2.5 mL; control) for 7 d. For each period, blood and milk samples were collected from d -4 to 14 (relative to the first injection) to measure PRL, insulin-like growth factor-1, and cortisol concentrations. In addition, blood samples were collected during morning milking on d -4, 2, and 7 to determine the milking-induced PRL release. Mammary gland biopsies were collected on the last day of injections. Milk fat samples were collected from d 1 to 7 and on d 14. The mRNA levels of genes encoding proteins related to mammary activity (α-lactalbumin, ß-casein, and acetyl-coenzyme A carboxylase), apoptosis (Bax, Bcl2, and caspase-3), PRL receptors (PRLR; long and short forms), signal transducer and activator of transcription 5 (STAT5A and STAT5B), and suppressors of cytokine signaling (SOCS2 and SOCS3) were evaluated by real-time reverse transcription PCR using RNA extracted from milk fat and mammary biopsies. Milk production was decreased moderately (about 9%) by E2 injections during the treatment period. Estradiol injections increased basal PRL levels in serum and milk but did not affect milking-induced PRL release. Estradiol injections increased the plasma concentration of insulin-like growth factor-1 but did not affect cortisol concentration during the treatment period. In mammary tissue, the expression of Bcl2 was downregulated, whereas that of STAT5A and B and the Bax:Bcl2 mRNA ratio was higher during E2 injections. The total STAT5 protein content in mammary tissue was elevated by E2 injections. We found no significant difference observed for the other genes in mammary tissue or milk fat. The present data do not support the contention that E2 injections inhibit milk production by interfering with PRL signaling, but enhanced basal PRL concentration and STAT5 gene expression in mammary tissue.


Assuntos
Estradiol/farmacologia , Estrogênios/farmacologia , Expressão Gênica/efeitos dos fármacos , Glândulas Mamárias Animais/efeitos dos fármacos , Leite/metabolismo , Prolactina/sangue , Animais , Bovinos , Estradiol/administração & dosagem , Estrogênios/administração & dosagem , Feminino , Lactação , Glândulas Mamárias Animais/metabolismo
7.
Radiol Med ; 118(1): 152-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22580807

RESUMO

PURPOSE: We evaluated the experience with and efficacy of stent-grafting for iatrogenic peripheral arterial ruptures. MATERIALS AND METHODS: From 2005 to 2009 we performed stent-grafting on four male patients (age 38-67 years) with iatrogenic peripheral arterial ruptures. In patient 1, grointissue necrosis followed a subcutaneous injection and led to femoral arterial rupture. Pseudoaneurysms ruptured in patients 2 and 3 who were undergoing femoral arteriotomy. Patient 1 experienced a ruptured carotid artery during neck surgery. Shock occurred in three of the four patients. Four patients underwent self-expanding stent-grafting (8 mm×60 mm or 8 mm×80 mm) under local anaesthesia. RESULTS: Haemorrhages were controlled in all patients. No procedure-related complications occurred. Patient 1 died of lung metastases 13 months after stent-grafting. Follow-up examinations showed that the stent-graft remained patent in patients 1, 2 and 4, whereas stent occlusion occurred after 15 months in patient 3; in this case, a pseudoaneurysm proximal to the stent was identified, and although repeat stent-grafting successfully stopped the bleeding, the patient died of multiple organ failure 1 week later. CONCLUSIONS: Emergency stent-grafting is a technically feasible and therapeutically effective modality for treating high-risk patients who experience iatrogenic peripheral arterial ruptures. The efficient treatment of hypotension and early endovascular intervention will improve the prognosis.


Assuntos
Falso Aneurisma/etiologia , Falso Aneurisma/cirurgia , Aneurisma Roto/etiologia , Aneurisma Roto/cirurgia , Implante de Prótese Vascular/métodos , Artéria Femoral/lesões , Doenças Vasculares Periféricas/etiologia , Doenças Vasculares Periféricas/cirurgia , Stents , Adulto , Idoso , Falso Aneurisma/diagnóstico por imagem , Aneurisma Roto/diagnóstico por imagem , Angiografia , Meios de Contraste , Tratamento de Emergência , Humanos , Doença Iatrogênica , Masculino , Pessoa de Meia-Idade , Doenças Vasculares Periféricas/diagnóstico por imagem , Resultado do Tratamento , Ultrassonografia
8.
Eur Rev Med Pharmacol Sci ; 24(7): 3710-3716, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32329847

RESUMO

OBJECTIVE: To study the influences of micro ribonucleic acid (miR)-214 on the proliferation and apoptosis of oral cancer cells through the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) pathway. MATERIALS AND METHODS: In this work, human oral cancer HB cell lines were cultured in vitro and then treated with phosphate-buffered saline (PBS) as Control group, with miR-214 mimics as miR-214 mimics group or with miR-214 mimics + ERK inhibitor U0126 as miR-214 mimics + U0126 group. The messenger RNA (mRNA) levels of miR-214 and ERK were determined using quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR), and the protein expression levels of phosphorylated ERK (p-ERK), ERK, proliferating cell nuclear antigen (PCNA), p21, and tubulin were measured via Western blotting (WB). Besides, the proliferation and apoptosis of cells in each group were evaluated via methyl thiazolyl tetrazolium (MTT) assay and Hoechst staining, respectively. RESULTS: Compared with Control group, miR-214 mimics group exhibited increased expression of miR-214 in oral cancer cells (p<0.01), extremely raised expression levels of p-ERK and PCNA, but an extremely decreased protein expression level of p21 (p<0.01), whereas miR-214 mimics + U0126 group had remarkably lower levels of p-ERK and PCNA, and a considerably higher protein level of p21 than miR-214 mimics group (p<0.05). The qRT-PCR results showed no significant differences in the mRNA level of ERK among the three groups (p>0.05). In addition, the proliferation ability was enhanced successively in Control group, miR-214 mimics + U0126 group and miR-214 mimics group, and the increase was more notable in miR-214 mimics group, with statistically significant differences (p<0.05). Finally, it was found through the Hoechst apoptosis assay that compared with that in Control group, the cell apoptosis was notably inhibited in miR-214 mimics group, and it was greatly increased in miR-214 mimics + U0126 group. CONCLUSIONS: MiR-214 increases p-ERK level and p-ERK/ERK to activate the MAPK/ERK signaling pathway, raise PCNA level, and decrease p21 level, thereby promoting cell proliferation and inhibiting cell apoptosis.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , MicroRNAs/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neoplasias Bucais/metabolismo , Apoptose , Proliferação de Células , Humanos , Sistema de Sinalização das MAP Quinases , MicroRNAs/genética , Neoplasias Bucais/patologia , Transdução de Sinais , Células Tumorais Cultivadas
9.
Trop Biomed ; 34(4): 991-999, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33592970

RESUMO

Anaplasmosis and theileriosis are significant tick-borne diseases threatening the livestock industry worldwide. In the present study, we screened 127 cattle and 115 sheep blood DNA samples from northeastern China for Theileria and Anaplasma pathogens by polymerase chain reaction (PCR) using species-specific primers. The result showed that only Theileria orientalis and Anaplasma ovis were detected, with a prevalence of 2.9% for T. orientalis in cattle and 57.4% for A. ovis in sheep. Fragments of Anaplasma ovis major surface protein 4 (AoMSP4) and Theileria orientalis major piroplasm surface protein (ToMPSP) genes were sequenced for phylogenetic analysis. Sequence analysis showed that the AoMSP4 gene was conserved, with 100% sequence identity value among sheep samples. However, the ToMPSP gene was relatively diverse, with sequence identity ranging from 87.6%-99l.0% among cattle samples. Phylogenetic analysis showed that the ToMPSP gene sequences isolated from 4 cattle samples were classified into type 1, type 2 and type 7, while the AoMSP4 gene sequences obtained from 66 sheep were classified into genotype I, according to the neighbour-joining distance method. This study provides important data for understanding the epidemiology of tick-borne diseases and genetic diversity of these pathogens in the northeast region of China.

10.
Eur Rev Med Pharmacol Sci ; 20(18): 3886-3890, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27735026

RESUMO

OBJECTIVE: We conducted a comparison of the diagnostic kit for quantification of hepatitis B virus DNA (PCR-fluorescence probing) and COBAS TaqMan automated nucleic acid extraction and real-time polymerase chain reaction (PCR) amplification systems. We tested their capacity to quantify and diagnose patients with chronic viral hepatitis B with low viral load < 1 x 103 IU/mL, in hope to provide further evidence for promoting the application of COBAS TaqMan as the diagnostic method for such patients. PATIENTS AND METHODS: Diagnostic kit and COBAS TaqMan system were tested on 100 patients diagnosed with chronic viral hepatitis B in our hospital and with a viral load lower than the detection limit of real-time extraction-quantification kit. These patients included 47 cases with chronic viral HBV, 53 cases of HBV-associated cirrhosis (11 cases were HBV-associated liver cancer with cirrhosis). COBAS TaqMan real-time quantification PCR with a sensitivity of 20 IU/ml was performed to test the reproducibility for the diagnosis result. RESULTS: The COBAS TaqMan real-time system quantified 76 cases out of 100 with a viral load higher than 20 IU/ml (detection rate, 76%). Among these patients, there were 33 cases of chronic viral HBV (without cirrhosis) (detection rate, 70.2%), 43 cases of cirrhosis (detection rate, 81.1%, including 28 cases of compensatory cirrhosis and 15 cases of decompensated cirrhosis), and 11 cases of liver cancer (detection rate, 81.2%). CONCLUSIONS: The COBAS TaqMan system has higher sensitivity than traditional real-time PCR detection kit, especially for HBV-related cirrhosis and liver cancer with low viral load. The limitation of real-time PCR should be taken into account during treatment monitoring and the alternative of COBAS TaqMan system should be promoted in patients with high risk of liver cirrhosis and cancer to avoid delayed diagnosis and improve clinical outcome.


Assuntos
DNA Viral , Vírus da Hepatite B/genética , Hepatite B/diagnóstico , Técnicas de Amplificação de Ácido Nucleico , Reação em Cadeia da Polimerase , Adulto , DNA Viral/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Taq Polimerase , Carga Viral
11.
Hum Immunol ; 56(1-2): 114-24, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9455500

RESUMO

A murine monoclonal antibody (mAb), 928, that recognizes a cell surface antigen (928 Ag) on a human Epstein-Barr virus-transformed fetal liver-derived lymphoid progenitor cell line (FL4.4) was generated. The 928 mAb reacted with only FL4.4; it did not react with any other 57 cell lines tested. Two color flowcytometry analysis of peripheral blood mononuclear cells (PBMC) revealed that the 928 mAb reacted with B cell and monocyte fractions from only two individuals out of 63 unrelated donors. Biochemical analyses showed that the 928 Ag composes of two molecules (33 and 34 Kd) and forms a SDS-resistant, noncovalently linked dimer conformation, the feature being similar to that of peptide-bound MHC class II molecules. Treatment of FL4.4 cells with the 928 mAb significantly facilitated homotypic cell aggregation. In addition, treatment of PBMC of the 928 Ag+ donor with recombinant IL-4 augmented the expression of the 928 Ag on CD64+ monocytes. Typing of HLA-DRB1, DPA1 and DPB1 alleles of the 928 Ag expressing and nonexpressing cells revealed that the 928 Ag is expressed only on PBMC of HLA-DPA1*0201 and DPB1*0301 positive donors. Finally, anti-DP antibody precleared 928 Ag from the cell lysate. These results demonstrate that the 928 mAb recognizes a polymorphic determinant of HLA-DPA1*0201-DPB1*0301 gene products. The possibility that amino acids in the groove of the peptide-binding site of HLA-DP molecules are critical for the 928 epitope is discussed.


Assuntos
Anticorpos Monoclonais/imunologia , Epitopos/análise , Antígenos HLA-DP/imunologia , Animais , Especificidade de Anticorpos , Antígenos de Superfície/imunologia , Agregação Celular , Epitopos/química , Expressão Gênica , Genes MHC da Classe II , Antígenos HLA-DP/química , Humanos , Hibridomas/imunologia , Interleucina-4/imunologia , Leucócitos Mononucleares/imunologia , Camundongos , Camundongos Endogâmicos BALB C
12.
Bone Marrow Transplant ; 27(6): 601-6, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11319589

RESUMO

Refractory acute lymphoblastic leukemia (ALL) is often incurable, and relapse rates following allogeneic bone marrow transplantation (BMT) remain high. We have reported that patients who develop increased numbers of gammadelta(+) T cells soon after BMT are significantly less likely to relapse. We now show in seven donor/recipient pairs that donor-derived Vdelta1(+)CD4(-)CD8(-)gammadelta(+) T cells are activated and proliferate in response to recipient primary ALL blasts. In addition, these cells have been shown to bind and lyse the recipient ALL blasts. Separately, gammadelta(+) T cells proliferate poorly or not at all in mixed lymphocyte culture against HLA-mismatched unrelated stimulator cells. These observations suggest that allogeneic gammadelta(+) T cells could be an effective immunotherapeutic strategy against refractory disease without the risk of graft-versus-host disease.


Assuntos
Efeito Enxerto vs Leucemia/imunologia , Linfocinas/fisiologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Linfócitos T Citotóxicos/imunologia , Citotoxicidade Imunológica , Humanos , Imunoterapia/métodos , Teste de Cultura Mista de Linfócitos , Monócitos/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Células Tumorais Cultivadas/imunologia
13.
J Orthop Res ; 14(4): 639-46, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8764875

RESUMO

A computer controlled wrist joint motion simulator has been developed that actively moves forearms from cadavers through cyclic planar flexion-extension motions, planar radial-ulnar deviation motions, and combined motions such as circumduction. Hybrid position-force feedback control algorithms are used to determine the wrist flexor and extensor tendon forces necessary to achieve the desired motions. The simulator was used in a series of 12 fresh cadaver forearms to produce both flexion-extension and radial-ulnar deviation motions and was found to cause repeatable, physiological movements. In these experiments, the extensor tendon forces were greater than those of the flexors, typically by a factor of two.


Assuntos
Movimento/fisiologia , Punho/fisiologia , Fenômenos Biomecânicos , Cadáver , Simulação por Computador , Humanos
15.
Bioresour Technol ; 100(3): 1108-14, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18793845

RESUMO

The start-up and operational performance (total 212 days, including the start-up of 164 days) of an anaerobic baffled reactor (ABR), which is used to treat heavy oil produced water, was studied without the temperature control. Inoculums were mixtures of acclimated sediment taken from a heavy oil produced water treatment plant and digested sludge from a sewage wastewater treatment plant. The rod-shaped and spherical granules with colors of henna and black, in which Clostridia, Methanosarcina and Methanothrx sp. were main populations, were observed in each compartment of ABR after the reactor's successful start-up (day 164). Rhodopseudomonas with the activity of lipase and halotolerant, as a kind of photosynthetic bacteria, was also observed in the first five compartments. X-ray diffraction (XRD) showed that the spherical granule sludge was compact and contained a large amount of organics, amorphous materials, and crystals of Fe(2)O(3), FeS, and CaCO(3), whereas the rod-shaped granule sludge was incompact without crystals of Fe(2)O(3), FeS, and CaCO(3). Scanning electron microscope (SEM) showed that the skeleton construction of this rod-shaped granule was filamentous bacteria and amount of extracellular polymeric substances (EPS). The ABR, after successful start up, can achieve high average chemical oxygen demand (COD) and oil removals of 65% and 88% for heavy oil produced water with poor nutrient (COD:TN:TP, 1200:15:1) and high salt concentration (1.15-1.46%), respectively. Furthermore, ABR kept stable during 2.5 times the COD level shock load (0.50 kg COD m-3 d-1) for four days.


Assuntos
Bactérias Anaeróbias/metabolismo , Reatores Biológicos/microbiologia , Petróleo , Sais/química , Poluentes Químicos da Água/metabolismo , Purificação da Água/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos
16.
Immunology ; 96(1): 48-56, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10233677

RESUMO

Previously we described a monoclonal antibody (mAb) that reacted with a cell-surface antigen, immature thymocyte antigen-1 (IMT-1), which is expressed on thymocytes of late CD4- CD8- (double negative) to early CD4+ CD8+ (double positive) differentiation stages. In this study, we investigated the expression of IMT-1 on various cell lineages in thymus as well as in peripheral lymphoid organs. We found that IMT-1 is expressed on T-cell receptor (TCR)-betalo and TCR-deltalo thymocytes, but not on TCR-betahi, TCR-deltahi or natural killer (NK)1.1+ thymocytes, or on peripheral alpha beta or gamma delta T cells. We also investigated the kinetics of expression of IMT-1 during fetal thymocyte development and compared it with the expression of the pre-TCR complex, comprising CD3, pre-TCR-alpha (pTalpha) and TCR-beta. We found that expression of both was similar, starting at day 14.5 of gestation, peaking on day 16.5 and gradually decreasing thereafter. Furthermore, the expression of both IMT-1 and pTalpha was drastically reduced when DN thymocytes in recombination activating gene (RAG)-2-/- mice were challenged in vivo with anti-CD3 mAb. These results indicate that IMT-1 is expressed on not only immature thymocytes of alpha beta T-cell lineage but also on those of gamma delta T-cell lineage, and that the expression of IMT-1 and the pre-TCR complex is co-ordinately regulated during the alpha beta lineage thymocyte development.


Assuntos
Antígenos de Diferenciação de Linfócitos T/metabolismo , Complexo Receptor-CD3 de Antígeno de Linfócitos T/metabolismo , Receptores de Antígenos de Linfócitos T alfa-beta , Receptores de Antígenos de Linfócitos T gama-delta , Linfócitos T/citologia , Timo/embriologia , Animais , Anticorpos Monoclonais/farmacologia , Biomarcadores/análise , Complexo CD3/imunologia , Diferenciação Celular , Citometria de Fluxo , Proteínas de Homeodomínio/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Mutantes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T/imunologia , Linfócitos T/metabolismo , Timo/imunologia
17.
Int Immunol ; 10(7): 951-60, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9701033

RESUMO

Previously, we described a mAb (1-23) reacting with a novel cell surface antigen expressed on thymocytes at late CD4-CD8- [(double negative (DN)] to early CD4+CD8+ [(double positive (DP)] differentiation stage. Since the expression of this molecule was restricted to immature thymocytes, we designated it as immature thymocyte antigen-1 (IMT-1). In this study, we have investigated the relevance of IMT-1 expression to thymocyte selection using TCR transgenic mice, scid mice or RAG-2-/- mice. The IMT-1+ population in DP thymocytes was decreased in the thymuses of MHC class I-restricted or class II-restricted TCR transgenic mice with a positively selecting MHC background when compared with that of the mice with a non-selecting MHC background. IMT-1+ DP thymocytes were also decreased in TCR transgenic mice in which negative selection occurs. When DP thymocytes in H-Y TCR transgenic mice were stimulated with CD3epsilon mAb in vitro as well as in vivo, the expression of IMT-1 on DP thymocytes was decreased. Furthermore, the expression of IMT-1 on DN thymocytes from RAG-2-/- mice was drastically reduced when CD3epsilon mAb was challenged in vivo. These results suggest that the expression of IMT-1 on DP or DN thymocytes is down-regulated by stimulation through TCR as well as pre-TCR. Taken together, these results show that IMT-1 is a unique surface marker which exquisitely separates pre-selected thymocytes from post-selected thymocytes.


Assuntos
Antígenos de Diferenciação de Linfócitos T/fisiologia , Linfócitos T/citologia , Linfócitos T/imunologia , Timo/citologia , Timo/imunologia , Animais , Anticorpos Monoclonais/farmacologia , Antígenos de Diferenciação de Linfócitos T/biossíntese , Antígenos de Diferenciação de Linfócitos T/imunologia , Complexo CD3/imunologia , Antígenos CD4/biossíntese , Antígenos CD8/biossíntese , Diferenciação Celular/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos T/fisiologia , Transdução de Sinais/fisiologia , Estimulação Química , Linfócitos T/metabolismo , Timo/metabolismo
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