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1.
Adv Sci (Weinh) ; 11(6): e2305913, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38059822

RESUMO

Surgical removal of the thyroid gland (TG) for treating thyroid disorders leaves the patients on lifelong hormone replacement that partially compensates the physiological needs, but regenerating TG is challenging. Here, an approach is reported to regenerate TG within the spleen for fully restoring the thyroid's functions in mice, by transplanting thyroid tissue blocks to the spleen. Within 48 h, the transplanted tissue efficiently revascularizes, forming thyroid follicles similar to the native gland after 4 weeks. Structurally, the ectopically generated thyroid integrates with the surrounding splenic tissue while maintaining its integrity, separate from the lymphatic tissue. Functionally, it fully restores the native functions of the TG in hormone regulation in response to physiological stimuli, outperforming the established method of oral levothyroxine therapy in maintaining systemic homeostasis. The study demonstrates the full restoration of thyroid functions post-thyroidectomy by intrasplenic TG regeneration, providing fresh insights for designing novel therapies for thyroid-related disorders.


Assuntos
Neoplasias da Glândula Tireoide , Tireoidectomia , Humanos , Animais , Camundongos , Tireoidectomia/métodos , Neoplasias da Glândula Tireoide/cirurgia , Baço/cirurgia , Regeneração , Hormônios
3.
Ying Yong Sheng Tai Xue Bao ; 34(5): 1178-1186, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37236933

RESUMO

Funiu Mountains are located in a transition region between warm temperate zone and northern subtropical region, where a variety of plant species are distributed with sensitive response to climate change. Their response characteristics to climate change are still unclear. We developed the basal area increment (BAI) index chronologies of Pinus tabuliformis, P. armandii, and P. massoniana in the Funiu Mountains to examine their growth trend and their sensitivity to climatic change. The results showed that the BAI chronologies gave a clue that the three conife-rous species had similar radial growth rate. The large Gleichlufigkeit (GLK) indices among the three BAI chronologies also indicated that the three species had a similar growth trend. Results of correlation analysis showed that the three species also had similar response to climatic change to a certain extent. Radial growth of all the three species was significantly positively correlated with the total monthly precipitation in December of previous year and June of the current year, but negatively correlated with the precipitation in September and the mean monthly temperature in June of the current year. There were some differences in the responses of the three coniferous to climate change. P. massoniana had a significant negative correlation with the mean temperature in March, and a significant positive correlation with the precipitation in March, while P. armandii and P. massoniana were affected negatively by the maximum temperature in August. Results of the moving correlation analysis showed that the three coniferous species had some similar sensitivity to climate change. Their positive responses to precipitation in previous December consistently increased, as well as the negative correlation with precipitation in current September. As to P. masso-niana, they had a relatively stronger climatic sensitivity and higher stability than the other two species. It would be more suitable for P. massoniana trees on the southern slope of the Funiu Mountains under global warming.


Assuntos
Pinus , Traqueófitas , Mudança Climática , Árvores , China , Aquecimento Global
4.
Ann Vasc Surg ; 93: 216-223, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36805427

RESUMO

BACKGROUND: This retrospective study aimed to evaluate the safety and efficacy of cutting balloon angioplasty and conventional balloon angioplasty in supra-aortic arterial lesions caused by Takayasu arteritis. METHODS: A total of 46 patients with supra-aortic arterial lesions between January 2011 and December 2018 were included. Cutting balloon angioplasty was applied for 17 patients with 24 supra-aortic arterial lesions (group A), while 29 patients with 36 supra-aortic arterial lesions received conventional balloon angioplasty (group B). The preoperative clinical manifestation, operation result, and postoperative outcomes were recorded and compared in the 2 groups. RESULTS: Dizziness, visual disturbance, and unequal/absent pulses were the most common manifestations. The technical success of revascularization was 93.5% (43/46) in patients and 93.3% (56/60) in lesions. The stent implantation rate in group A was significantly lower than that in group B (4.2% vs. 50% in lesions, P < 0.05). Restenosis was the most common complication in both groups. Although the early (≤30 days) and late (>30 days) complications in group A were less than those in group B, there was no significant difference between the 2 groups (P > 0.05). Moreover, the primary-assisted patency of cutting balloon angioplasty and conventional balloon angioplasty at 1, 2, and 5 years were 66.7%, 62.5%, and 62.5% and 61.1%, 58.2%, and 49.8%, there was no significant difference between the 2 groups (P > 0.05), respectively. CONCLUSIONS: Compared with conventional balloon angioplasty, cutting balloon angioplasty could be considered a safe and effective alternative for supra-aortic arterial lesions caused by Takayasu arteritis, demonstrating better patency and clinical benefit.


Assuntos
Angioplastia com Balão , Arterite de Takayasu , Humanos , Estudos Retrospectivos , Arterite de Takayasu/complicações , Arterite de Takayasu/diagnóstico por imagem , Arterite de Takayasu/terapia , Resultado do Tratamento , Stents , Angioplastia , Angioplastia com Balão/efeitos adversos
5.
World J Clin Cases ; 10(28): 10339-10345, 2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36246839

RESUMO

BACKGROUND: Chronic myeloid leukemia (CML) is a malignant hematologic malignancy that can progress to blast phase with a myeloid or lymphoid phenotype. Some patients with CML can also progress to blast crisis phase; however, the transformation of CML into Philadelphia-positive lymphoma is extremely rare. CASE SUMMARY: We present a patient with CML who experienced a sudden transformation to anaplastic large-cell lymphoma (ALCL) after 7 mo of treatment with imatinib, during which she had achieved partial cytogenetic response as well as early molecular response. The patient noticed a mass in her left shoulder, the biopsy data of which were consistent with ALCL; moreover, her lymphoma cells exhibited BCR-ABL gene fusion. The patient was diagnosed with Philadelphia-positive ALCL that progressed from CML, and was thus treated with the second generation tyrosine kinase inhibitor nilotinib. Six months later, the mass had totally disappeared and the BCR-ABL fusion gene was undetectable in the peripheral blood. To our knowledge, this is the first patient known to have developed Philadelphia-positive ALCL transformed from CML. CONCLUSION: Unexplained lymphadenopathy or an extramedullary mass in a patient with CML may warrant a biopsy and testing for BCR-ABL fusion.

6.
Int Orthop ; 45(3): 673-679, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33452537

RESUMO

PURPOSE: This study aims to analyze the gait characteristics of the elderly patients with lumbar spinal stenosis by an intelligent device for energy expenditure and activity (IDEEA) to assist clinical work. METHODS: A total of 98 subjects were included in this study from January 2017 to December 2018. A total of 49 elderly outpatients with symptomatic lumbar spinal stenosis in unilateral lower extremity were included as the experimental group, and another 49 healthy subjects matched with gender, age, and body mass index (BMI) were analyzed as the control group. The gait data of the subjects (including single support, double support, SLS/DLS, swing duration, step duration, cycle duration, pulling accel, swing power, ground impact, foot fall, foot off, push off, speed, cadence, step length, and stride length) were collected to compare between the experience group and control group, the affected leg and the healthy leg in experimental group. RESULTS: The results of this study presented that small intermittent claudication occurred in all patients. The time of single support was significantly increased (p < 0.05). Double support, step duration, and pulling accel were increased (p < 0.05), and the Push off, speed, step length, and Stride length were decreased (p < 0.05) in the experimental group compared with the control group. CONCLUSION: Small intermittent claudication was the basic gait composition of the elderly patients with lumbar spinal stenosis that can reflect the abnormal gait characteristics by IDEEA.


Assuntos
Estenose Espinal , Idoso , , Marcha , Análise da Marcha , Humanos , Claudicação Intermitente , Estenose Espinal/diagnóstico
7.
J Endovasc Ther ; 28(1): 44-52, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32748684

RESUMO

Purpose: To report the findings of an in vitro experiment to evaluate the quality of needle fenestrations dilated by different size balloons in various stent-grafts and to investigate the differences between gradual and rapid dilation. Materials and Methods: Fenestrations were made using an 18-G needle in 5 different polyester or expanded polytetrafluoroethylene (ePTFE) stent-grafts: Relay, Valiant, Hercules, TAG, and Ankura. Each stent-graft received 2 groups of fenestrations: one was followed by gradual sequential dilation (4-, 6-, 8-, and 10-mm balloons) and the other by rapid dilation (4- and 10-mm balloons). The pressure was increased to 10 atmospheres or until the balloon was fully inflated with no waist. Quantitative and qualitative evaluations, including fenestration diameter, area, shape, and margins were conducted using light microscopy and scanning electron microscopy. Results: Relay had the strongest resistance to dilation and Ankura the slightest. The maximum length and area of holes expanded as the balloon diameter increased. The fenestrations in polyester devices were mostly elliptical or slit-like, with limited tears but extensive fibers visible in the margin, while ePTFE stent-grafts showed larger fenestration areas with clearer margins. Ankura showed the best quality of fenestrations, which were always circular or square without fabric tears, while the holes in the TAG were square or elliptical but sometimes had a slit after large balloon dilation (≥6 mm). The Relay, Valiant, Hercules, and Ankura devices showed no difference in maximum diameter, fenestration area, or scores of shape and margin (p>0.05). Rapid dilation in the TAG increased the rate of uncontrolled fabric tear, resulting in a larger final diameter (12.90 vs 10.82 mm, p=0.047), smaller area (30.46 vs 41.09 mm2, p=0.028), worse shape (0.75 vs 1.20, p=0.268), and worse margin (0.40 vs 1.00, p=0.174). Though the decreased fenestration shape and margin scores did not reach statistical significance, the trend for decline was more obvious than with the other devices. Conclusion: Materials and structures of the stent-grafts determine the quality of fenestrations dilated by different size balloons. The use of sequential vs rapid balloon dilation is also crucial for fashioning high-quality fenestrations and should be selected judiciously.


Assuntos
Stents , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Dilatação , Humanos , Teste de Materiais , Desenho de Prótese , Resultado do Tratamento
8.
Lab Invest ; 101(3): 341-352, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33318617

RESUMO

Acute myelogenous leukemia (AML) is the most common acute leukemia in adults. Despite great progress has been made in this field, the pathogenesis of AML is still not fully understood. We report here the biological role of lncRNA small nucleolar RNA host gene 5 (SNHG5) in the pathogenesis of AML and the underlying mechanisms. The results showed that lncRNA SNHG5 was highly expressed in AML cancer cell lines. In vitro studies displayed that inhibition of SNHG5 with shRNA resulted in suppression of survival, cell cycle progression, migration/invasion of AML and capacity of adhesion and angiogenesis in human umbilical vein endothelial cells. Mechanistic studies revealed a SNHG5/miR-26b/connective tissue growth factor (CTGF)/vascular endothelial growth factor A (VEGFA) axis in the regulation of AML angiogenesis. Finally, Yin Yang 1 (YY1) was found to transactivate and interact with SNHG5 promoter, leading to the upregulation of SNHG5 in AML. Collectively, upregulation of lncRNA SNHG5 mediated by YY1, activates CTGF/VEGFA via targeting miR-26b to regulate angiogenesis of AML. Our work provides new insights into the molecular mechanisms of AML.


Assuntos
Leucemia Mieloide Aguda/metabolismo , Neovascularização Patológica/genética , RNA Longo não Codificante/genética , Fator de Transcrição YY1/genética , Adulto , Linhagem Celular Tumoral , Sobrevivência Celular , Fator de Crescimento do Tecido Conjuntivo/genética , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Feminino , Humanos , Leucemia Mieloide Aguda/genética , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Transdução de Sinais/genética , Regulação para Cima/genética , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator de Transcrição YY1/metabolismo
9.
World J Clin Cases ; 8(11): 2144-2149, 2020 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-32548144

RESUMO

BACKGROUND: Hemodialysis is an advanced blood purification technique to manage kidney failure. However, for conventional hemodialysis, the high prevalence of dyslipidemia may cause cardiovascular diseases and an increase in mortality. Moreover, toxins accumulating in the body over time may induce some complications. High flux hemodialysis can effectively improve disease indexes and clinical symptoms. AIM: To investigate the efficacy of high flux hemodialysis in elderly patients with chronic kidney failure (CKF). METHODS: A total of 66 elderly patients with CKF who were admitted to our hospital from October 2017 to October 2018 were included in the study. According to the therapies they received, the patients were divided into a study group and a control group with 33 patients in each group. The study group received high flux hemodialysis and the control group received conventional dialysis treatment. Kidney function, toxin levels in serum, and complications were compared in the two groups. RESULTS: Before the treatment, there was no significant difference in kidney function, ß2-microglobulin, or blood urea nitrogen between the two groups (P > 0.05). In contrast, kidney function was better in the study group than in the control group after the treatment (P < 0.05). In addition, the study group had significantly lower parathyroid hormone and serum cystatin C than the control group (P < 0.05). The incidence of complications was 8.57% in the study group, which was lower than that of the control group (20.00%; P < 0.05). CONCLUSION: High flux hemodialysis may improve kidney function and reduce toxin levels in serum and the incidence of complications in elderly patients with CKF.

10.
Environ Sci Pollut Res Int ; 26(24): 24840-24849, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31240652

RESUMO

In mountainous areas, rock fragments (RFs) are a common feature on the soil surface and in topsoil. Few studies, however, have investigated the spatial distribution of RFs and the relevant mechanisms underpinning their distribution on steep hillslopes, especially in karst regions. We have collected and measured the RF cover, size, and content at the soil surface and within the topsoil of secondary forest, man-made forest, and non-forest land hillslopes in a karst region in Yunnan Province, southwest China. The results revealed no significant relationships between slope position and mean total RF coverage, median diameter (D50), and mean total volumetric RF in topsoil within the three karst hillslopes covered by different types of vegetation. A limited effect of vegetation on the spatial distribution of RFs on the hillslopes was identified. However, the variation in RFs in the topsoil between the top and bottom slopes was greater than that at the surface between the top and bottom slopes, implying that underground leakage was greater than surface runoff.


Assuntos
Florestas , Geologia/métodos , Solo , China , Solo/química
11.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-701112

RESUMO

AIM:To study the value of copeptin(CPP)level for the prediction of cardiorenal syndrome (CRS)in the rats with subtotal nephrectomy(SNX)combined with myocardial infarction(MI).METHODS: Male SD rats(n=60)were divided into blank control group(Con group), renal failure group(SNX group), heart failure group (MI group)and heart failure+renal failure group(CRS group).The concentrations of CPP in the serum and urine,hemo-dynamic indexes,blood pressure and renal function indexes were measured 1~5 weeks after modeling.The predictive val-ue of CPP for CRS in the rats was evaluated by the receiver operating characteristic(ROC)curve.RESULTS:Compared with Con group,left ventricular systolic pressure(LVSP)at 9 d in CRS group was significantly decreased(P<0.05),left ventricular end-diastolic pressure(LVEDP)at 9 d in CRS group was significantly increased(P<0.05), and the differ-ence of blood pressure at each time point was not statistically significant.The levels of blood urea nitrogen(BUN)and uri-nary creatinine(Ucr)in CRS group were significantly increased at 1 and 3 weeks(P<0.05).Compared with Con group, serum CPP level was significantly increased at 1,3 and 5 weeks(P<0.05), and urine CPP level was significantly in-creased at 3 weeks in CRS group.Serum brain natriuretic peptide(BNP)level was significantly increased at 1 and 3 weeks,while urine BNP level was significantly increased at 5 weeks after modeling in CRS group(P<0.05).No correla-tion between serum or urine CPP and BNP or BUN levels at 1 week in CRS group was observed.The results of ROC curve analysis indicated that the area under the curve(AUC)of serum CPP was 0.908(95%CI:0.789~1.028),and the cut-off value was 56.59 ng/L(sensitivity 0.875,specificity 0.800).CONCLUSION:The combination of SNX and MI estab-lishes a CRS rat model with both heart and kidney injury,and serum CPP can be used as a sensitive and specific biomarker for early prediction of CRS.

12.
Biomed Pharmacother ; 95: 31-36, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28826094

RESUMO

Hepatocellular carcinoma-related protein 1 (HCRP1), also known as the homologue of vacuolar protein sorting 37A (hVps37A), serves as a membrane trafficking complex to mediate internalization and degradation of ubiquitinated membrane receptors. Recently, more and more researchers have showed that HCRP1 plays a critical role in tumorigenesis. However, the biological roles of HCRP1 in glioma remain to be elucidated. In the present study, we detected the expression pattern of HCRP1 in glioma. The results showed that HCRP1 was significantly down-regulated in glioma tissues and cell lines. On the basis of further analysis, we demonstrated that up-regulation of HCRP1 efficiently inhibited glioma cell proliferation and invasion in vitro, and as well as suppressed glioma cell growth in vivo. In addition, we found that HCRP1 up-regulation decreased the levels of p-ERK and p-AKT in glioma cells. We also emphasized that the ERK and AKT signaling pathways were the mechanisms underlying the inhibitory effect of HCRP1 on glioma cells. Taken together, we provided evidence in support of the prognostic value of HCRP1 in glioma and suggested it as a promising target for glioma treatment.


Assuntos
Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Glioma/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Regulação para Cima , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo , MAP Quinases Reguladas por Sinal Extracelular/genética , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Invasividade Neoplásica , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais/fisiologia
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 171: 126-131, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27497864

RESUMO

A series of blue-emitting Ba5-xCl(PO4)3:xEu2+ (0.004≤x≤0.016) phosphors were synthesized by conventional high-temperature solid state reaction. The structure and photoluminescence (PL) properties of the phosphors were investigated. The as-prepared phosphors exhibit broad excitation band ranging from 250 to 420nm, and strong asymmetric blue emission band peaking at 436nm. The optimum concentration of Eu2+ in the Ba5Cl(PO4)3:Eu2+ phosphor is x=0.01, and the concentration quenching mechanism is verified to be the combined actions of dipole-dipole interaction and radiation re-absorption mechanism. The thermal stability of Ba5Cl(PO4)3:Eu2+ was evaluated by temperature-dependent PL spectra. Compared with that of commercial BaMgAl10O17:Eu2+ (BAM) phosphor, the Ba5-xCl(PO4)3:xEu2+ phosphors exhibit similarly excellent thermal quenching property. In addition, the CIE chromaticity coordinates of Ba5-xCl(PO4)3:xEu2+ (0.004≤x≤0.016) were calculated to evaluate the color quality. All the results indicate that Ba5Cl(PO4)3:Eu2+ is a promising candidate phosphor for near-ultraviolet (n-UV) pumped LED.

14.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 23(5): 1286-91, 2015 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-26524024

RESUMO

OBJECTIVE: To investigate the effect of CXCR4 gene on the proliferation, adhesion, invasion and tumorigenicity of a human monocytic leukemic cell line SHI-1. METHODS: The lentivirus vector silencing the expression of CXCR4 was constructed for infection of SHI-1 cells silencing expression of CXCR4 in SHI-1 cells. The expression of CXCR4, MMP-2 and MMP-9 was detected by real time PCR. The expression of CXCR4 on membrane of SHI-1 cells was detected by flow cytometry. The SHI-1 cell proliferation ability was detected by MTT. The co-culture system of the leukemia cells and bone marrow stromal cells was used to detect the adhesion and migration ability of leukemia cells. SHI-1 cells were inoculated subcutaneously in nude mice to investigate the growth ability in vivo. RESULTS: After SHI-1 cells were infected by lentivirus silencing expression of CXCR4, the expression of CXCR4 mRNA in SHI-1 CXCR-4i cells decreased by 76% as compared with expression of SHI-1/NC of negative control virus, the expression of CXCR4 on membrane of SHI-1/CXCR4i obviously downregulated; the expression of MMP-2 and MMP-9 in SHI-1/CXCRi cells also declined by 63% and 62% respectively; the proliferation ability of SHI-1/CXCR4i in vitro did not obviously changed, but the adhesion and trans-matrigel invasion ability significantly decreased, the SHI-1/CXCR4i cells could not form neoplasm subcutaneously in mice, but the SHI-1 and SHI-1/NC cells could form neoplasm subcutaneously in mice, and there was no significant difference in volumn of neoplasm mass. CONCLUSION: The silencing expression of CXCR4 can decline the adhesion and migration ability of SHI-1 cells, and can completely suppress the formation of neoplasm subcutaneously, so the CXCR4 may serve as a target for treating leukemia.


Assuntos
Leucemia Monocítica Aguda/patologia , Interferência de RNA , Receptores CXCR4/genética , Animais , Adesão Celular , Linhagem Celular Tumoral , Proliferação de Células , Técnicas de Cocultura , Humanos , Lentivirus , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Células-Tronco Mesenquimais , Camundongos , Camundongos Nus , Invasividade Neoplásica , RNA Mensageiro , Transdução de Sinais
15.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 22(5): 1326-30, 2014 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-25338582

RESUMO

This study was purposed to investigate the expression of heat shock protein 90 (HSP90) in peripheral blood plasma of patients with multipl myeloma (MM), and to explore its possible role in the pathogenesis of MM, and its relationship with treatment, prognosis and the outcome of patients. The peripheral blood samples from 58 patients with MM and 20 healthy volunteers were collected. The plasma concentration of HSP90 in patients and healthy volunteers was measured by ELISA. The results showed that the concentration of HSP90 in peripheral blood of patients with MM was significantly higher than that in the healthy volunteers [(32.398 ± 3.674) vs (25.762 ± 2.916) ng/ml] (P < 0.001). The concentration of HSP90 showed positively correlation with International Staging System(ISS) stage, therapeutic response, frequency of plasmocyte, globulin, immune globulin, M-protein, ß2 micro-globulin, and light chain of MM patients (P < 0.05) ; while it showed little correlation with sex, age and type of MM patients (P > 0.05) . It is concluded that the HSP90 may be involved in the occurrence and development of MM. Detection of HSP90 in plasma would contribute to judge the clinical course, therapeutic efficacy and prognosis of MM patients.


Assuntos
Proteínas de Choque Térmico HSP90/sangue , Mieloma Múltiplo/sangue , Humanos , Proteínas do Mieloma , Prognóstico
16.
BMC Genomics ; 15: 793, 2014 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-25218338

RESUMO

BACKGROUND: Phage ZZ1, which efficiently infects pathogenic Acinetobacter baumannii strains, is the fifth completely sequenced T4-like Acinetobacter phage to date. To gain a better understanding of the genetic characteristics of ZZ1, bioinformatics and comparative genomic analyses of the T4 phages were performed. RESULTS: The 166,687-bp double-stranded DNA genome of ZZ1 has the lowest GC content (34.4%) of the sequenced T4-like Acinetobacter phages. A total of 256 protein-coding genes and 8 tRNA genes were predicted. Forty-three percent of the predicted ZZ1 proteins share up to 73% amino acid identity with T4 proteins, and the homologous genes generally retained the same order and transcriptional direction. Beyond the conserved structural and DNA replication modules, T4 and ZZ1 have diverged substantially by the acquisition and deletion of large blocks of unrelated genes, especially in the first halves of their genomes. In addition, ZZ1 and the four other T4-like Acinetobacter phage genomes (Acj9, Acj61, 133, and Ac42) share a well-organised and highly conserved core genome, particularly in the regions encoding DNA replication and virion structural proteins. Of the ZZ1 proteins, 70, 64, 61, and 56% share up to 86, 85, 81, and 83% amino acid identity with Acj9, Acj61, 133, and Ac42 proteins, respectively. ZZ1 has a different number and types of tRNAs than the other 4 Acinetobacter phages, although some of the ZZ1-encoded tRNAs share high sequence similarity with the tRNAs from these phages. Over half of ZZ1-encoded tRNAs (5 out of 8) are related to optimal codon usage for ZZ1 proteins. However, this correlation was not present in any of the other 4 Acinetobacter phages. CONCLUSIONS: The comparative genomic analysis of these phages provided some new insights into the evolution and diversity of Acinetobacter phages, which might elucidate the evolutionary origin and host-specific adaptation of these phages.


Assuntos
Acinetobacter/virologia , Bacteriófago T4/genética , Bacteriófago T4/fisiologia , Genoma Viral/genética , Composição de Bases , Códon/genética , Elementos de DNA Transponíveis/genética , Evolução Molecular , Genômica , Anotação de Sequência Molecular , Filogenia , RNA de Transferência/genética
17.
Chin Med J (Engl) ; 126(14): 2731-5, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23876905

RESUMO

BACKGROUND: Interactions of tumor cells with the microenvironment were deemed to promote the tumor invasion and metastasis. CXC chemokine receptor 4 (CXCR4) and extracellular matrix metalloproteinase inducer (EMMPRIN) had reported to participate in this process. However the roles of bone marrow microenvironment in leukemic infiltration were not well investigated. METHODS: A co-culture system between SHI-1 cells and bone marrow stromal cells (BMSCs) is used to simulate the interactions of leukemic cells with their microenvironment. The trans-matrigel invasion was used to detect the capability of SHI-1 cells invasion. The BMSCs and SHI-1 cells were mixed in a ratio of 1:10 and added to the millicell chamber coated with matrigel. Either the co-culture supernatant or the functional blocking peptide of CXCR4 and EMMPRIN were added to the trans-matrigel invasion system. The expressions of EMMPRIN in SHI-1 cells and BMSCs were detected by RT-PCR. The changes of the expression of matrix metalloproteinase-2, 9 (MMP-2, MMP-9), tissue inhibitor of metalloproteinase 2 (TIMP-2), and CXCR4 mRNA in SHI-1 cells were determined by real-time PCR. The concentration of stromal cell derived factor 1 (SDF-1) in serum free supernatant was measured by ELISA. RESULTS: Both SHI-1 cells and BMSCs express EMMPRIN. SHI-1 cells could hardly invade the matrigel membrane; the coculture supernatant did not induce the invasion of SHI-1 cells. When contacting directly with BMSCs, SHI-1 cells invaded to the lower chamber of millicell were significantly increased. The functional blocking peptide of CXCR4 and EMMPRIN could significantly inhibit the invasion triggered by BMSCs. When co-culturing with BMSCs, the expression of CXCR4, MMP-2, MMP-9 and TIMP-2 mRNA in SHI-1 cells were significantly elevated in company with a significantly higher level of SDF-1 in the co-cultured serum-free supernatant. CONCLUSION: The interactions of leukemic cells and BMSCs play important roles in leukemic cell infiltration.


Assuntos
Comunicação Celular , Leucemia Monocítica Aguda/patologia , Células-Tronco Mesenquimais/fisiologia , Basigina/fisiologia , Linhagem Celular Tumoral , Técnicas de Cocultura , Humanos , Invasividade Neoplásica , Receptores CXCR4/fisiologia
18.
BMC Microbiol ; 12: 156, 2012 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-22838726

RESUMO

BACKGROUND: Acinetobacter baumannii, a significant nosocomial pathogen, has evolved resistance to almost all conventional antimicrobial drugs. Bacteriophage therapy is a potential alternative treatment for multidrug-resistant bacterial infections. In this study, one lytic bacteriophage, ZZ1, which infects A. baumannii and has a broad host range, was selected for characterization. RESULTS: Phage ZZ1 and 3 of its natural hosts, A. baumanni clinical isolates AB09V, AB0902, and AB0901, are described in this study. The 3 strains have different sensitivities to ZZ1, but they have the same sensitivity to antibiotics. They are resistant to almost all of the antibiotics tested, except for polymyxin. Several aspects of the life cycle of ZZ1 were investigated using the sensitive strain AB09V under optimal growth conditions. ZZ1 is highly infectious with a short latent period (9 min) and a large burst size (200 PFU/cell). It exhibited the most powerful antibacterial activity at temperatures ranging from 35°C to 39°C. Moreover, when ZZ1 alone was incubated at different pHs and different temperatures, the phage was stable over a wide pH range (4 to 9) and at extreme temperatures (between 50°C and 60°C). ZZ1 possesses a 100-nm icosahedral head containing double-stranded DNA with a total length of 166,682 bp and a 120-nm long contractile tail. Morphologically, it could be classified as a member of the Myoviridae family and the Caudovirales order. Bioinformatic analysis of the phage whole genome sequence further suggested that ZZ1 was more likely to be a new member of the Myoviridae phages. Most of the predicted ORFs of the phage were similar to the predicted ORFs from other Acinetobacter phages. CONCLUSION: The phage ZZ1 has a relatively broad lytic spectrum, high pH stability, strong heat resistance, and efficient antibacterial potential at body temperature. These characteristics greatly increase the utility of this phage as an antibacterial agent; thus, it should be further investigated.


Assuntos
Acinetobacter baumannii/virologia , Bacteriófagos/isolamento & purificação , Bacteriófagos/fisiologia , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/isolamento & purificação , Antibacterianos/farmacologia , Bacteriófagos/genética , Bacteriófagos/ultraestrutura , Caudovirales/genética , Caudovirales/isolamento & purificação , Caudovirales/fisiologia , Caudovirales/ultraestrutura , DNA Viral/química , DNA Viral/genética , Farmacorresistência Bacteriana Múltipla , Ordem dos Genes , Genoma Viral , Especificidade de Hospedeiro , Humanos , Concentração de Íons de Hidrogênio , Viabilidade Microbiana/efeitos dos fármacos , Viabilidade Microbiana/efeitos da radiação , Dados de Sequência Molecular , Myoviridae/genética , Myoviridae/isolamento & purificação , Myoviridae/fisiologia , Myoviridae/ultraestrutura , Fases de Leitura Aberta , Análise de Sequência de DNA , Temperatura , Vírion/ultraestrutura
19.
FEMS Microbiol Lett ; 323(2): 180-7, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22092718

RESUMO

Mip (macrophage infectivity potentiator) and Mip-like proteins have been demonstrated to be involved in virulence of several animal pathogens, but as yet none of their native bacterial targets has been identified. Our previous work demonstrated that the Mip-like protein found in the plant pathogen Xanthomonas campestris pv. campestris (Xcc) (hereafter called Mip(Xcc)) is also involved in virulence. Inactivation of the mip(Xcc) gene leads to a significant reduction in exopolysaccharide production and extracellular protease activity via an unknown mechanism. The Xcc genome encodes six extracellular proteases, all of which are secreted via the type II secretion system. The serine protease PrtA makes the largest contribution to Xcc's total extracellular proteolytic activity. In this study, Western blotting analysis demonstrated that Mip(Xcc) was located in the periplasm. Bacterial two-hybrid and far-Western analysis indicated that Mip(Xcc) interacted with PrtA directly. Purified Mip(Xcc) was found to be able to rescue the protease activity of periplasmic proteins extracted from the mip(Xcc) mutant. These findings show that Mip(Xcc) plays a role in the maturation of PrtA, which is the novel native target for at least one Mip or Mip-like protein.


Assuntos
Proteínas de Bactérias/metabolismo , Peptídeo Hidrolases/metabolismo , Fatores de Virulência/metabolismo , Xanthomonas campestris/enzimologia , Proteínas de Bactérias/genética , Far-Western Blotting , Western Blotting , Técnicas de Inativação de Genes , Peptídeo Hidrolases/genética , Proteínas Periplásmicas/genética , Proteínas Periplásmicas/metabolismo , Ligação Proteica , Mapeamento de Interação de Proteínas , Técnicas do Sistema de Duplo-Híbrido , Fatores de Virulência/genética , Xanthomonas campestris/genética
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