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1.
J Coll Physicians Surg Pak ; 33(10): 1113-1117, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37804015

RESUMEN

OBJECTIVE: To investigate the changes in volumetric bone mineral density (vBMD) assessed by quantitative computed tomography (QCT) in chronic kidney disease (CKD) patients on maintenance dialysis. STUDY DESIGN: Descriptive study. Place and Duration of the Study: Department of Radiology, The Second Affiliated Hospital of Anhui Medical University, Hefei, China, from March to July 2022. METHODOLOGY: Maintenance dialysis patients were selected for this study, and parameters related to renal function and bone metabolism markers were recorded. Patients undergoing routine physical examination were age-matched with maintenance dialysis patients to serve as the control group. vBMD scans of the lumbar spine (L1-3) were obtained by QCT for all participants. RESULTS: Among the 141 maintenance dialysis patients, there were 67 patients with secondary hyperparathyroidism (SHPT) and 74 patients with non-secondary hyperparathyroidism (non-SHPT) with mean vBMDs of 145.99±55.13 mg/cm3 and 129.10±44.20 mg/cm3, respectively. The 159 individuals in the control group had mean age of 52.77±11.66 years and mean vBMD of 129.62±36.36 mg/cm3. The vBMD of the SHPT group was greater than that of both the non-SHPT group and the control group (all p<0.05). For dialysis patients, vBMD was positively correlated with calcium-phosphorus product and intact parathyroid hormone (iPTH) levels (r = 0.181, 0.214, respectively, p<0.05); vBMD was inversely correlated with age (r = -0.555, p<0.05). After adjusting for the covariates, vBMD remained positively correlated with iPTH (r = 0.184, p<0.05). CONCLUSION: Increased lumbar vertebral vBMD in maintenance dialysis patients may be associated with high iPTH, providing clinicians with a new understanding of the changes in bone mineral density in maintenance dialysis patients. KEY WORDS: Bone mineral density, Quantitative computed tomography, Chronic kidney disease, Maintenance dialysis.


Asunto(s)
Hiperparatiroidismo Secundario , Insuficiencia Renal Crónica , Humanos , Adulto , Persona de Mediana Edad , Densidad Ósea , Diálisis Renal/efectos adversos , Tomografía Computarizada por Rayos X/métodos , Hiperparatiroidismo Secundario/etiología , Hiperparatiroidismo Secundario/complicaciones , Vértebras Lumbares/diagnóstico por imagen , Hormona Paratiroidea , Insuficiencia Renal Crónica/complicaciones
2.
Can J Gastroenterol Hepatol ; 2022: 2249447, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35775068

RESUMEN

Purpose: To develop and validate a radiomic nomogram based on texture features from out-of-phase T1W images and clinical biomarkers in prediction of liver fibrosis. Materials and Methods: Patients clinically diagnosed with chronic liver fibrosis who underwent liver biopsy and noncontrast MRI were enrolled. All patients were assigned to the nonsignificant fibrosis group with fibrosis stage <2 and the significant fibrosis group with stage ≥2. Texture parameters were extracted from out-of-phase T1-weighted (T1W) images and calculated using the Artificial Intelligent Kit (AK). Boruta and LASSO regressions were used for feature selection and a multivariable logistic regression was used for construction of a combinational model integrating radiomics and clinical biomarkers. The performance of the models was assessed by using the receiver operator curve (ROC) and decision curve. Results: ROC analysis of the radiomics model that included the most discriminative features showed AUCs of the training and test groups were 0.80 and 0.78. A combinational model integrating RADscore and fibrosis 4 index was established. ROC analysis of the training and test groups showed good to excellent performance with AUC of 0.93 and 0.86. Decision curves showed the combinational model added more net benefit than radiomic and clinical models alone. Conclusions: The study presents a combinational model that incorporates RADscore and clinical biomarkers, which is promising in classification of liver fibrosis.


Asunto(s)
Cirrosis Hepática , Imagen por Resonancia Magnética , Área Bajo la Curva , Biomarcadores , Humanos , Cirrosis Hepática/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Nomogramas , Estudios Retrospectivos
3.
Front Chem ; 10: 841151, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35372278

RESUMEN

A class of iodobenzoyldiazenido-functionalized POMs (TBA)3 [Mo6O18(=N=NCOAr)] (Ar = Ph-o-I (1); Ph-m-I (2); Ph-p-I (3); Ph-3,4-I2 (4); Ph-2,3,5-I3 (5) (TBA = tetrabutylammonium) were prepared via the refluxing reaction of α-octamolybdates, DCC, and corresponding hydrazides in dry acetonitrile. Their structures were determined by Fourier-transform infrared spectroscopy, ultraviolet-visible spectra, X-ray photoelectron spectroscopy, hydrogen-1 nuclear magnetic resonance, and high-resolution mass spectrometry. Research on the biological activity of title compounds shows that L3, L5, 3, and 5 demonstrate potent inhibitory activity against coxsackievirus B3 and low in vitro cytotoxic activity against Hep-2 cell lines. The covalent linkage between the iodobenzoyldiazenido components and POMs can enhance the molecular inhibitory efficiency of iodobenzohydrazides.

4.
Front Chem ; 10: 814880, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35186882

RESUMEN

Mucin 1 (MUC1), a well-known tumor-associated antigen and attractive target for tumor immunotherapy, is overexpressed in most human epithelial adenomas with aberrant glycosylation. However, its low immunogenicity impedes the development of MUC1-targeted antitumor vaccines. In this study, we investigated three liposomal adjuvant systems containing toll-like receptor 4 (TLR4) agonist monophosphoryl lipid A (MPLA) and auxiliary lipids of different charges: cationic lipid dimethyldioctadecylammonium (DDA), neutral lipid distearoylglycerophosphocholine (DSPC) or anionic lipid dioleoylphosphatidylglycerol (DOPG), respectively. ELISA assay evidenced that the positively charged DDA/MPLA liposomes are potent immune activators, which induced remarkable levels of anti-MUC1 antibodies and exhibited robust Th1-biased immune responses. Importantly, the antibodies induced by DDA/MPLA liposomes efficiently recognized and killed MUC1-positive tumor cells through complement-mediated cytotoxicity. In addition, antibody titers in mice immunized with P2-MUC1 vaccine were significantly higher than those from mice immunized with P1-MUC1 or MUC1 vaccine, which indicated that the lipid conjugated on MUC1 antigen also played important role for immunomodulation. This study suggested that the liposomal DDA/MPLA with lipid-MUC1 is a promising antitumor vaccine, which can be used for the immunotherapy of various epithelial carcinomas represented by breast cancer.

5.
Eur Neurol ; 84(5): 361-367, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34315157

RESUMEN

INTRODUCTION: This study aims to analyze the permeability of intra- and peri-meningiomas regions and compare the microvascular permeability between peritumoral brain edema (PTBE) and non-PTBE using DCE-MRI. METHODS: This was a retrospective of patients with meningioma who underwent surgery. The patients were grouped as PTBE and non-PTBE. The DCE-MRI quantitative parameters, including volume transfer constant (Ktrans), rate constant (Kep), extracellular volume (Ve), and mean plasma volume (Vp), obtained using the extended Tofts-Kety 2-compartment model. Logistic regression analysis was conducted to explore the risk factor of PTBE. RESULTS: Sixty-three patients, diagnosed as fibrous meningioma, were included in this study. They were 17 males and 46 females, aged from 32 to 88 years old. Kep and Vp were significantly lower in patients with PTBE compared with those without (Kep: 0.1852 ± 0.0369 vs. 0.5087 ± 0.1590, p = 0.010; Vp: 0.0090 ± 0.0020 vs. 0.0521 ± 0.0262, p = 0.007), while there were no differences regarding Ktrans and Ve (both p > 0.05). The multivariable analysis showed that tumor size ≥10 cm3 (OR = 4.457, 95% CI: 1.322-15.031, p = 0.016) and Vp (OR = 0.572, 95%CI: 0.333-0.981, p = 0.044) were independently associated with PTBE in patients with meningiomas. CONCLUSION: DCE-magnetic resonance imaging·Meningioma·Blood vessel MRI can be used to quantify the microvascular permeability of PTBE in patients with meningioma.


Asunto(s)
Edema Encefálico , Neoplasias Meníngeas , Meningioma , Adulto , Anciano , Anciano de 80 o más Años , Edema Encefálico/diagnóstico por imagen , Edema Encefálico/etiología , Permeabilidad Capilar , Medios de Contraste , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Neoplasias Meníngeas/diagnóstico por imagen , Meningioma/diagnóstico por imagen , Persona de Mediana Edad , Estudios Retrospectivos
6.
Can J Gastroenterol Hepatol ; 2021: 6677821, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33791254

RESUMEN

Purpose. To compare the diagnostic value of texture analysis- (TA-) derived parameters from out-of-phase T1W, in-phase T1W, and T2W images in the classification of the early stage of liver fibrosis. Methods. Patients clinically diagnosed with hepatitis B infection, who underwent liver biopsy and noncontrast MRI scans, were enrolled. TA parameters were extracted from out-of-phase T1-weighted (T1W), in-phase T1W, and T2-weighted (T2W) images and calculated using Artificial Intelligent Kit (AK). Features were extracted including first-order, shape, gray-level cooccurrence matrix, gray-level run-length matrix, neighboring gray one tone difference matrix, and gray-level differential matrix. After statistical analyses, final diagnostic models were constructed. Receiver operating curves (ROCs) and areas under the ROC (AUCs) were used to assess the diagnostic value of each final model and 100-time repeated cross-validation was applied to assess the stability of the logistic regression models. Results. A total of 57 patients were enrolled in this study, with 27 in the fibrosis stage < 2 and 30 in stages ≥ 2. Overall, 851 features were extracted per ROI. Eight features with high correlation were selected by the maximum relevance method in each sequence, and all had a good diagnostic performance. ROC analysis of the final models showed that all sequences had a preferable performance with AUCs of 0.87, 0.90, and 0.96 in T2W and in-phase and out-of-phase T1W, respectively. Cross-validation results reported the following values of mean accuracy, specificity, and sensitivity: 0.98 each for out-of-phase T1W; 0.90, 0.89, and 0.90 for in-phase T1W; and 0.86, 0.88, 0.84 for T2W in the training set, and 0.76, 0.81, and 0.72 for out-of-phase T1W; 0.74, 0.72, and 0.75 for in-phase T1W; and 0.63, 0.64, and 0.63 for T2W for the test group, respectively. Conclusion. Noncontrast MRI scans with texture analysis are viable for classifying the early stages of liver fibrosis, exhibiting excellent diagnostic performance.


Asunto(s)
Cirrosis Hepática , Imagen por Resonancia Magnética , Área Bajo la Curva , Biopsia , Humanos , Cirrosis Hepática/diagnóstico por imagen , Curva ROC
7.
Front Neurol ; 12: 749931, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35185748

RESUMEN

OBJECTIVE: To establish the relationship between hematoma sites of involvement and hematoma expansion (HE) in patients with deep intracerebral hemorrhage (ICH). METHODS: Eligible patients with deep ICH admitted to hospital within 6 hours of onset between 2018 and 2020 were included in this retrospective multi-center study. Individuals with secondary ICH were excluded. The volume of HE was evaluated based on admission and follow-up computed tomography scans. Associations between deep ICH sites of involvement and HE were examined using multivariable logistic regression analysis while adjusting for confounding covariates of HE. RESULTS: We enrolled 583 individuals from three stroke centers. Data from a final total of 460 patients were used in the analysis; of these patients, 159 (34.6%) had HE. In the crude model without adjustment, external capsule, anterior limb of the internal capsule, and posterior limb of the internal capsule (PLIC) involvement were correlated with HE. After fully adjusted models for sex, age, intraventricular hemorrhage, Glasgow Coma Scale admission score, baseline ICH volume, and time from onset to initial computed tomography, multivariable logistic regression revealed that the PLIC is a robust predictor of HE in patients with deep ICH (adjusted odds ratio = 2.73; 95% confidence interval = 1.75-4.26; p < 0.001). CONCLUSION: Involvement of the posterior limb of the internal capsule in deep hemorrhage could be a promising predictor of HE.

8.
World J Clin Cases ; 8(18): 4272-4279, 2020 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-33024789

RESUMEN

BACKGROUND: Lymphoplasmacyte-rich meningioma (LPRM) is one of the rarest variants of meningioma and is classified as grade I (benign) tumor. It is characterized by abundant infiltrates of lymphocytes and plasma cells. Here, we report an extremely rare case of LPRM with an atypical imaging finding of multiple cysts around a solid mass. CASE SUMMARY: The patient was a 36-year-old man with intermittent headache, dizziness, and vomiting for 2 years. Computed tomography and magnetic resonance imaging presented a cystic solid mass in the right frontal lobe with heavy peritumoral edema and obvious contrast enhancement. The patient was treated with right frontotemporal craniotomy, and gross total resection of the tumor was achieved without adjuvant therapy. There was no clinical or neuroradiological evidence of recurrent or residual tumor for 3 years after initial surgery. CONCLUSION: LPRM is one of the rarest variants of meningioma. Although, the mass of this case had common features, multiple cysts with nonuniform size and thin wall around the solid part are uncommon imaging finding, increasing the rate of misdiagnosis. The definitive diagnosis of LPRM relies on histopathological findings.

9.
Biochem Biophys Res Commun ; 523(2): 535-541, 2020 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-31928714

RESUMEN

Renal cell carcinoma (RCC) is the most common malignant kidney tumors in adults. Von Hippel-Lindau (VHL) gene is deficient in >50% of RCC cases, but the role of VHL as a potential therapeutic target in RCC has not been well established. In the present study, 9-cis-Retinoic acid, which is a potent natural agonist of retinoid X receptors (RXRs), was found to decrease the viability of VHL-proficient RCC cells, but had little effect on VHL-deficient RCC cells. In addition, it was demonstrated that VHL transcriptionally regulated RXRα in a hypoxia-inducible factor-α independent manner. Moreover, a negative correlation was observed between the expressions of VHL and RXRα in RCC tissues. Collectively, these data indicate that VHL-proficient RCC patients may be more sensitive to treatment with 9-cis-retinoic acid, which acts by regulating RXRα expression, compared with VHL-deficient RCC patients. The findings of the present study demonstrate a novel function of VHL and highlight the potential of VHL expression as a therapeutic modality for the optimized treatment of RCC patients.


Asunto(s)
Alitretinoína/farmacología , Carcinoma de Células Renales/tratamiento farmacológico , Neoplasias Renales/tratamiento farmacológico , Receptor alfa X Retinoide/metabolismo , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismo , Antineoplásicos/farmacología , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Receptor alfa X Retinoide/agonistas , Receptor alfa X Retinoide/genética , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/genética
10.
Biomark Med ; 12(12): 1347-1359, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30507300

RESUMEN

It has become increasingly clear that the development of cancer, a multifactorial disease, cannot be explained by a single molecule or gene mutation. As a new discipline, metabolomics focuses on the body's metabolite changes, and attempts to find differences to explain the development of cancer; it has proven to be effective and credible. Metabolic studies of bladder cancer (BCa) lag behind those of other tumors. This review systematically outlines the specific process of metabolomics and the use of metabolomics in BCa studies in recent years. We have reviewed the in vitro cell line, bladder tumor tissue and biofluid (urine, plasma and serum) studies used in metabolomics analyses of BCa. The advantages and drawbacks of the use of different samples were compared. Based on the available studies, we have further described the aberrant metabolic pathways of BCa and have suggested some metabolites that may be potential biomarkers for BCa detection.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Metabolómica/métodos , Neoplasias de la Vejiga Urinaria/metabolismo , Humanos , Flujo de Trabajo
11.
BMC Urol ; 18(1): 79, 2018 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-30200918

RESUMEN

BACKGROUND: BRAF-activated long non-coding RNA (BANCR) has been associated with various types of cancer. Nevertheless, the role of BANCR in clear cell renal cell carcinoma (ccRCC) is still not fully understood. This study aims to investigate the relationship between ccRCC and BANCR. METHODS: Expression of BANCR in TCGA renal cancer data sets was analyzed. The expression pattern of BANCR in Immortalized normal human proximal tubule epithelial cell line HK-2 and ccRCC cell lines (ACHN, CAKI-1, A498 and 786-O) was detected by real-time quantitative RT-PCR (qRT-PCR). ccRCC tissues with adjacent normal renal tissues diagnosed by pathological methods from 62 patients were used to detect the expression of BANCR, and its correlation with prognosis of ccRCC patients was assessed by Kaplan-Meier method. The LV-BANCR vector was used to examine the influence of BANCR on the proliferation, migration, invasion, apoptosis and cell cycle distribution of ccRCC cells in vitro. RESULTS: BANCR was downregulated in renal cancer according to TCGA data sets. Compared with adjacent normal renal tissues and normal human proximal tubule epithelial cell line HK-2, BANCR expression was significantly decreased in ccRCC tissues and ccRCC cell lines, and its low expression was associated with poor prognosis. Moreover, in the condition of BANCR overexpression by LV-BANCR vector, the proliferation, migration, invasion capacity of ccRCC cells was inhibited, while the apoptosis was increased and the G1 cell cycle arrest was induced in vitro. CONCLUSIONS: BANCR is downregulated in ccRCC tissues and cell lines, and is associated with ccRCC progression. Thus, BANCR may represent a novel prognostic biomarker and a potential therapeutic target for ccRCC patients.


Asunto(s)
Carcinoma de Células Renales/metabolismo , Regulación Neoplásica de la Expresión Génica , Neoplasias Renales/metabolismo , Proteínas Proto-Oncogénicas B-raf/metabolismo , ARN Largo no Codificante/metabolismo , Biomarcadores de Tumor , Carcinoma de Células Renales/genética , Línea Celular Tumoral , Proliferación Celular , Regulación hacia Abajo , Humanos , Estimación de Kaplan-Meier , Riñón/metabolismo , Neoplasias Renales/genética , Pronóstico , Proteínas Proto-Oncogénicas B-raf/genética
12.
BMC Urol ; 17(1): 38, 2017 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-28558682

RESUMEN

BACKGROUND: Renal cell carcinoma (RCC) is one of the most common types of cancer in urological system worldwide. Recently, the anticancer role of Glucosamine has been studied in many types of cancer. The aim of this study was to investigate the effects of Glucosamine on RCC. METHODS: The effects of Glucosamine on RCC cell proliferation and apoptosis were investigated by MTT assay and Annexin V-FITC Apoptosis assay, respectively in vitro. Cell cycle was detected by flow cytometry after treatment with Glucosamine. Protein levels of several cell cycle associated markers were examined by Western Blot. RESULTS: Our data showed that Glucosamine significantly inhibited the proliferation of renal cancer 786-O and Caki-1 cells in a dose-dependent manner. Besides, Glucosamine treatment resulted in cell cycle arrest at G0/G1 phase in both cell lines. Meanwhile, the expression of several regulators that contribute to G1/S phased transition, such as Cyclin D1, CDK4 and CDK6, were significantly down-regulated with the up-regulation of cell cycle inhibitors, p21 and p53, after treatment with glucosamine. However, the apoptosis rate of RCC cells was down-regulated when treatment with Glucosamine at 1 mM and 5 mM, while up-regulated at 10 mM. CONCLUSIONS: Our findings indicated that Glucosamine inhibited the proliferation of RCC cells by promoting cell cycle arrest at G0/G1 phase, but not promoting apoptosis. The present results suggested that Glucosamine might be a potential therapeutic agent in RCC treatment in the future.


Asunto(s)
Carcinoma de Células Renales/patología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Glucosamina/farmacología , Neoplasias Renales/patología , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Fase G1/efectos de los fármacos , Humanos , Células Tumorales Cultivadas
13.
Sci Rep ; 7: 45135, 2017 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-28327626

RESUMEN

In this study, we aimed to investigate the intrinsic hippocampal functional connectivity (FC) network and its relationship with prospective memory in patients with breast cancer suffering from chemotherapy-induced cognitive impairment (CICI). Thirty-four breast cancer patients before and after adjuvant chemotherapy (CB and CC, respectively) and 31 age- and education-matched cognitively normal (CN) women were recruited and subjected to a prospective memory task and a resting-state functional magnetic resonance imaging scan. Seed-based functional connectivity analysis was used to compare the hippocampal FC networks between CC and CN groups. Partial correction analysis was used to examine the association between the hippocampal FC network and prospective memory in the CC group. The cancer group that underwent chemotherapy obtained significantly poorer scores than the CN group on mini-mental state examination, verbal fluency test, digit span, and prospective memory examination. Compared to the CN group, CC group showed increased hippocampal connectivity in the frontal and parietal cortex, precuneus, posterior cingulate cortex, and the cerebellum. In addition, the increasing hippocampal FC networks were negatively correlated with prospective memory performance in the CC group. These findings suggest maladaptive hippocampal functioning as a mechanism underlying the impairment of prospective memory in patients experiencing CICI.


Asunto(s)
Neoplasias de la Mama/complicaciones , Hipocampo/efectos de los fármacos , Hipocampo/fisiopatología , Trastornos de la Memoria/etiología , Trastornos de la Memoria/psicología , Descanso/psicología , Sobrevivientes , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Mapeo Encefálico , Neoplasias de la Mama/tratamiento farmacológico , Conectoma , Femenino , Hipocampo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad
14.
Angew Chem Int Ed Engl ; 56(1): 338-342, 2017 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-27900837

RESUMEN

Naphthols and 3-trifluoroethylidene oxindoles were found to undergo an asymmetric Friedel-Crafts alkylation/lactonization reaction, catalyzed by only 2.5 mol % of a quinine-derived squaramide catalyst, to afford the corresponding α-aryl-ß-trifluoromethyl dihydrocoumarin derivatives in high yields (up to 99 %) with excellent enantio- and diastereoselectivities (up to 98 % ee, >20:1 d.r.). Importantly, the lactonization proceeded by nucleophilic attack of the naphthol hydroxy group at the amide motif of the oxindoles under mild reaction conditions. This protocol represents a new strategy for the formation of dihydrocoumarins by an efficient intramolecular amide C-N bond-cleavage and esterification process.

15.
Inorg Chem ; 55(19): 9497-9500, 2016 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-27627649

RESUMEN

A new diiodo-bifunctionalized Anderson-Evans polyoxometalate (TBA)3[MnMo6O18{(OCH2)3CNHCO(C6H4-p-I)}2] (1; TBA = [(C4H9)4N]+) was prepared and used as a new platform to generate tunable rigid-molecular rods (2a-2c) via Sonogashira cross-coupling. Single-crystal X-ray diffraction analysis of 1 and 2c reveals that they are type B Anderson-Evans structures with molecular lengths of 23 and 38 Å, respectively.

16.
J Thromb Thrombolysis ; 28(2): 230-7, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18998199

RESUMEN

BACKGROUND: Hirudin is an anti-coagulative product of the salivary glands of the medicinal leech Hirudo medicinalis. It is a powerful and specific thrombin inhibitor. Peptides containing the RGD motif competitively inhibit the binding of fibrinogen to GP IIb/IIIa on the platelets, thus inhibiting platelet aggregation. RESULTS: We have constructed a recombinant RGD-hirudin (r-RGD-hirudin) by fusing the tripeptide RGD sequence to the native hirudin (wt-hirudin). The r-RGD-hirudin was expressed at high levels in Pichia pastoris, and was purified to approximately 97% homogeneity. The specific anti-thrombin activity of purified r-RGD-hirudin is 12,000 ATU/mg, which is equivalent to wt-hirudin, but only r-RGD-hirudin can inhibit platelet aggregation. The biological effects of r-RGD-hirudin on Thrombin Time (TT), Prothrombin Time (PT), Activated Partial Thromboplastin Time (APTT), Bleeding Time (BT), maximum platelet aggregation (PAGm) induced by ADP were studied in rabbit model and compared with that of wt-hirudin. The rabbits were infused r-RGD-hirudin had prolonged TT, PT, and aPTT which were similar to that of wt-hirudin; but only r-RGD-hirudin was capable of inhibiting PAGm. Histopathological analyses showed that r-RGD-hirudin was two to three times more effective than wt-hirudin in preventing thrombosis. CONCLUSIONS: r-RGD-hirudin can potentially be used as a novel anti-coagulant for the prevention of thrombosis after carotid artery anastomosis or in other thrombotic events.


Asunto(s)
Anticoagulantes/farmacología , Hirudinas/farmacología , Agregación Plaquetaria/efectos de los fármacos , Trombina/antagonistas & inhibidores , Animales , Tiempo de Sangría , Hirudinas/biosíntesis , Hirudinas/genética , Masculino , Pichia/genética , Pichia/metabolismo , Plásmidos/química , Ingeniería de Proteínas , Conejos , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/farmacología
17.
Inorg Chem ; 47(10): 4054-9, 2008 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-18410094

RESUMEN

Through the use of (Bu4N)2[Sn3S4(edt)3] (edt=SCH2CH2S(2-)) and Sn(SPh)4 as metalloligands, three neutral compounds have been obtained: [(Ph3P) 2Cu] 2SnS(edt)(2).2CH2Cl2.H2O (1a), [(Ph3P) 2Cu]2SnS(edt)2.2DMF.H2O (1b), and [(Ph3P)Cu] 2Sn(SPh)(6).3H 2O (2). Single-crystal X-ray diffraction studies revealed that compounds 1a and 1b contain the same neutral butterfly-like [(Ph3P)2Cu]2SnS(edt)2 cluster, which consists of one central SnS 5 dreich trigonal bipyramid sharing one vertex and two sides with two slightly distorted CuS 2P2 tetrahedrons. Compound 2 has a linear [(Ph3P)Cu]2Sn(SPh)6 cluster that is composed of a central distorted SnS 6 octahedron sharing two opposite planes with two slightly distorted CuS 3P tetrahedrons. Compound 1a exhibited an emission at 568 nm (tau=12.86 micros) in the solid state, while in CH 2Cl 2 solution, 1a exhibited a green emission at 534 nm (tau=4.75 micros). Compound 2 showed an intense red emission at 696 nm (tau=3.64 micros) upon excitation at 307 nm in the solid state.

18.
Inorg Chem ; 45(14): 5236-8, 2006 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-16813374

RESUMEN

Reaction of [Cu(PPh3)2(MeCN)2]ClO4 (1) and Sn(edt)2 (edt = ethane-1,2-dithiolate) in dichloromethane afforded a novel compound [Sn3Cu4(S2C2H4)6(mu3-O)(PPh3)4](ClO4)2 x 3 CH2Cl2 (2), which is the first example of the heptanuclear Sn(IV)-Cu(I) oxosulfur complex with a bottle-shaped cluster core. Complex 2 gives a blue-green luminescent emission in the solid state. Crystallographic data for 2: C87H90Cl8Cu4O9P4S12Sn3, trigonal, space group R3, M = 2682.02, a = 18.156(2) A, b = 18.156(2) A, c = 54.495(10) A, gamma = 120 degrees, V = 15558(4) A3, Z = 6 (T = 130.15 K).

19.
Sheng Wu Gong Cheng Xue Bao ; 20(1): 126-9, 2004 Jan.
Artículo en Chino | MEDLINE | ID: mdl-16108503

RESUMEN

Recombinant RGD-Hirudin ( r-RGD-Hirudin ) has double functions: anti-thrombin activity and anti-platelet aggregation activity. To identify these functions, the expression plasmid, RGD-Hirudin-pPIC9K, was constructed by inserting cDNA of RGD-hirudin in yeast expression vector pPIC9K. The high expression clone was gained after screening. This clone was fermented for 3 days. The r-RGD-hirudin was secreted into the culture. It was ultra-filtrated from culture supernatant, then after gel filtration chromatography and anion exchange chromatography, the purified r-RGD-hirudin was gained. Its purity was larger than 97% and its specific activity was 12 000 ATU/mg. The yield per liter culture of purified r-RGD-hirudin was 1 g and overall recovery yield was more than 75% . The purified r-RGD-hirudin was identified by reductive SDS-PAGE, anti-thrombin activity assay, anti-platelet aggregation assay, LC/MS and isoelectrofocusing assay. It is proved that r-RGD-Hirudin is ramification of wt-Hirudin and it has anti-thrombin activity and anti-platelet aggregation activity.


Asunto(s)
Fermentación , Hirudinas/biosíntesis , Proteínas Recombinantes/biosíntesis , Animales , Hirudinas/genética , Hirudinas/aislamiento & purificación , Hirudinas/farmacología , Masculino , Peso Molecular , Pichia/genética , Inhibidores de Agregación Plaquetaria/farmacología , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/farmacología
20.
Sheng Wu Gong Cheng Xue Bao ; 19(2): 217-22, 2003 Mar.
Artículo en Chino | MEDLINE | ID: mdl-15966325

RESUMEN

Tumor angiogenesis plays a pivotal role in the progress of tumor. Among the various endogenous angiogenic inhibitors discovered, the human plasminogen kringle 5 (K5) has been demonstrated to be a potential inhibitor of the proliferation and migration of vascular endothelial cells in vitro. The replication-incompetent adenovirus (Ad) vector Adeno-X-CMV-K5 (Ad-K5) (where CMV is cytomegalovirus) was constructed and its antiangiogenic effect was tested on vascular endothelial cell and tumor cell. For the construction, the K5 cDNA was fused in-frame with human plasminogen signal sequence and inserted into the eukaryotic expression vector pcDNA3 to form pcDNA3K5. The recombinant plasmid was subcloned into the shuttle plasmid pShuttle under the control of the constitutive CMV immediate-early promoter. The plasmid carrying the cDNA for K5 (pShuttleKS) was then recombined with the Adeno-X viral DNA and transformed into E. coli DH5alpha. The resultant recombinant plasmid pAd-K5 was transfected into human embryonic kidney (HEK) 293 cells with liposome. The adenovirus expressing human plasminogen kringle 5 (Ad-K5) was successfully packaged and propagated in 293 cells, as detected by the cytopathic effect (CPE) on the cells, and the viral titer in the supernatant was 5 x 10(8) pfu/mL by plaque assay. Both human umbilical vein endothelial cell line ECV304 and human breast carcinoma cell line MDA-MB-231 were infected with Ad-K5 and Ad-LacZ, which was used the negative control, and assayed by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Compared with uninfected control and Ad-LacZ infected control, Ad-K5 infected group at 80 MOI (multiplicity of infection) significantly inhibited ECV304 proliferation; the difference between uninfected control and Ad-LacZ infected control was not significant. In contrast, there was no significant difference in the proliferation of MDA-MB-231 among all the treatments. In addition, the Ad-K5 at 100 MOI inhibited the differentiation and tube formation of ECV304 on ECMatrix gel. These results suggested that the recombinant replication-defective Adenovirus expressing human plasminogen kringle 5 inhibited the proliferation, differentiation and tube formation of ECV304 and had no effect on the proliferation of MDA-MB-231. Adenovirus mediated human plasminogen kringle 5 gene therapy may be a potential treatment of cancer through angiogenesis inhibition.


Asunto(s)
Adenoviridae/genética , Vectores Genéticos/genética , Fragmentos de Péptidos/genética , Plasminógeno/genética , Línea Celular , Línea Celular Tumoral , Proliferación Celular , Humanos , Neovascularización Fisiológica/genética , Neovascularización Fisiológica/fisiología , Fragmentos de Péptidos/fisiología , Plasminógeno/fisiología , Reacción en Cadena de la Polimerasa
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