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1.
Braz. arch. biol. technol ; Braz. arch. biol. technol;65: e2210409, 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1364456

ABSTRACT

Abstract: Obtaining the accurate disparity of each pixel quickly is the goal of stereo matching, but it is very difficult for the 3D labels-based methods due to huge search space of 3D labels, especially for highresolution images. We present an novel two-stage optimization strategy to get the accurate disparity map for high-resolution stereo image efficiently, which includes feature points optimization and superpixel optimization. In the first stage, we construct the support points including edge points and robust points for triangulation, which is used to extract feature points and then perform spatial propagation and random refinement to get the candidate 3D label sets. In the stage of superpixel optimization, we update per pixel labels of the corresponding superpixels using the candidate label sets, and then perform spatial propagation and random refinement. In order to provide more prior information to identify weak texture and textureless areas, we design the weight combination of "intensity + gradient + binary image" for constructing an optimal minimum spanning tree (MST) to compute the aggregated matching cost, and obtain the labels of minimum aggregated matching cost. We also design local patch surrounding the corresponding superpixel to accelerate our algorithm in parallel. The experimental result shows that our method achieves a good trade-off between running time and accuracy, including KITTI and Middlebury benchmark, which are the standard benchmarks for testing the stereo matching methods.

2.
Electron. j. biotechnol ; Electron. j. biotechnol;50: 10-15, Mar. 2021. ilus, graf, tab
Article in English | LILACS | ID: biblio-1292308

ABSTRACT

BACKGROUND: LXYL-P1-2 is the first reported glycoside hydrolase that can catalyze the transformation of 7-b-xylosyl-10-deacetyltaxol (XDT) to 10-deacetyltaxol (DT) by removing the D-xylosyl group at the C7 position. Successful synthesis of paclitaxel by one-pot method combining the LXYL-P1-2 and 10- deacetylbaccatin III-10-b-O-acetyltransferase (DBAT) using XDT as a precursor, making LXYL-P1-2 a highly promising enzyme for the industrial production of paclitaxel. The aim of this study was to investigate the catalytic potential of LXYL-P1-2 stabilized on magnetic nanoparticles, the surface of which was modified by Ni2+-immobilized cross-linked Fe3O4@Histidine. RESULTS: The diameter of matrix was 20­40 nm. The Km value of the immobilized LXYL-P1-2 catalyzing XDT (0.145 mM) was lower than that of the free enzyme (0.452 mM), and the kcat/Km value of immobilized enzyme (12.952 mM s 1 ) was higher than the free form (8.622 mM s 1 ). The immobilized form maintained 50% of its original activity after 15 cycles of reuse. In addition, the stability of immobilized LXYL-P1-2, maintained 84.67% of its initial activity, improved in comparison with free form after 30 d storage at 4 C. CONCLUSIONS: This investigation not only provides an effective procedure for biocatalytic production of DT, but also gives an insight into the application of magnetic material immobilization technology.


Subject(s)
Paclitaxel/biosynthesis , Glycoside Hydrolases/metabolism , Kinetics , Enzymes, Immobilized , Nanoparticles , Magnets
3.
Braz J Cardiovasc Surg ; 36(3): 318-322, 2021 06 01.
Article in English | MEDLINE | ID: mdl-33355791

ABSTRACT

INTRODUCTION: The mouse heterotopic cardiac transplant model has been extensively used to explore transplant immunity. Although the cuff technique facilitates the operation, the procedure remains difficult, and vessel eversion is the most difficult step. Cuff movement and everted vessel wall slippage are the main adverse factors in vessel eversion. Traditional strategies to prevent these factors focus on cuff fixation, while more steps or surgical instruments would be required. METHODS: According to the reported protocols and our experience, the vessel eversion skills were modified and used for transplantation. Cardiac grafts from C57BL/6(H-2b) or BALB/c(H-2d) mice were transplanted into C57BL/6(H-2b) mice. The operating times of recent 90 operations, which were divided into 9 groups according to their sequence, were summarized and analyzed. RESULTS: The mouse cervical cardiac transplantation was successfully performed by using the modified vessel eversion skills. The cuff movement, which is the most important adverse factor to prevent vessel eversion, was effectively prevented. In the recent 90 operations, the total operating time was 47.3±7.9 min and the success rate was 98%. CONCLUSIONS: The modified surgical skills simplify the vessel eversion in mouse cervical cardiac transplantation with cuff technique, characterized by less cuff movement, fewer steps, and surgical instruments. Using these surgical skills, the transplant can be performed in a short time.


Subject(s)
Heart Transplantation , Animals , Disease Models, Animal , Humans , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Tissue Donors
4.
Acta Cir Bras ; 32(7): 523-532, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28793036

ABSTRACT

PURPOSE:: To investigate the effect of intravascular cooling on renal function after resuscitation. METHODS:: Twenty four pigs were randomized into three groups (n=8 in each group): therapeutic hypothermia group (TH group), normothermia group (NH group) and sham operation group (SHAM group). After 6 minutes of untreated VF, CPR was performed. Upon ROSC, the TH group received the intravascular cooling. The NH and SHAM group did not undergo therapeutic hypothermia. Haemodynamic parameters were recorded. The bloods were analyzed for serum creatinine (sCr), CysC and NGAL. The kidney was surgically removed observe pathologic changes under a light microscope. RESULTS:: The sCr increased in both TH and NH groups after ROSC, compared to baseline. Between two groups, the sCr and creatinine clearance (Cc) showed lower level in the TH group. The urine volume per hour in the TH group were higher during cooling. After resuscitation, NGAL and CysC in the NH group were higher than in the TH group. Under the light microscope, compared with the TH group, the renal injury was prominent in the NH group. CONCLUSION:: Mild hypothermia had a protection to renal ischemia reperfusion injury after resuscitation.


Subject(s)
Cardiopulmonary Resuscitation/adverse effects , Hypothermia, Induced/methods , Kidney/physiopathology , Reperfusion Injury/therapy , Animals , Disease Models, Animal , Male , Random Allocation , Reperfusion Injury/etiology , Reperfusion Injury/physiopathology , Swine
5.
Acta cir. bras ; Acta cir. bras;32(7): 523-532, July 2017. tab, graf
Article in English | LILACS | ID: biblio-886215

ABSTRACT

Abstract Purpose: To investigate the effect of intravascular cooling on renal function after resuscitation. Methods: Twenty four pigs were randomized into three groups (n=8 in each group): therapeutic hypothermia group (TH group), normothermia group (NH group) and sham operation group (SHAM group). After 6 minutes of untreated VF, CPR was performed. Upon ROSC, the TH group received the intravascular cooling. The NH and SHAM group did not undergo therapeutic hypothermia. Haemodynamic parameters were recorded. The bloods were analyzed for serum creatinine (sCr), CysC and NGAL. The kidney was surgically removed observe pathologic changes under a light microscope. Results: The sCr increased in both TH and NH groups after ROSC, compared to baseline. Between two groups, the sCr and creatinine clearance (Cc) showed lower level in the TH group. The urine volume per hour in the TH group were higher during cooling. After resuscitation, NGAL and CysC in the NH group were higher than in the TH group. Under the light microscope, compared with the TH group, the renal injury was prominent in the NH group. Conclusion: Mild hypothermia had a protection to renal ischemia reperfusion injury after resuscitation.


Subject(s)
Animals , Male , Reperfusion Injury/therapy , Cardiopulmonary Resuscitation/adverse effects , Hypothermia, Induced/methods , Kidney/physiopathology , Swine , Reperfusion Injury/etiology , Reperfusion Injury/physiopathology , Random Allocation , Disease Models, Animal
6.
Acta cir. bras. ; 32(7): 523-532, July 2017. tab, graf, ilus
Article in English | VETINDEX | ID: vti-17724

ABSTRACT

Purpose: To investigate the effect of intravascular cooling on renal function after resuscitation. Methods: Twenty four pigs were randomized into three groups (n=8 in each group): therapeutic hypothermia group (TH group), normothermia group (NH group) and sham operation group (SHAM group). After 6 minutes of untreated VF, CPR was performed. Upon ROSC, the TH group received the intravascular cooling. The NH and SHAM group did not undergo therapeutic hypothermia. Haemodynamic parameters were recorded. The bloods were analyzed for serum creatinine (sCr), CysC and NGAL. The kidney was surgically removed observe pathologic changes under a light microscope. Results: The sCr increased in both TH and NH groups after ROSC, compared to baseline. Between two groups, the sCr and creatinine clearance (Cc) showed lower level in the TH group. The urine volume per hour in the TH group were higher during cooling. After resuscitation, NGAL and CysC in the NH group were higher than in the TH group. Under the light microscope, compared with the TH group, the renal injury was prominent in the NH group. Conclusion: Mild hypothermia had a protection to renal ischemia reperfusion injury after resuscitation.(AU)


Subject(s)
Animals , Hypothermia/complications , Ischemia , Reperfusion , Cardiopulmonary Resuscitation/trends , Swine/abnormalities
7.
Electron. j. biotechnol ; Electron. j. biotechnol;19(3): 43-48, May 2016. ilus
Article in English | LILACS | ID: lil-787006

ABSTRACT

Background: D-Hydroxyphenylglycine is considered to be an important chiral molecular building-block of antibiotic reagents such as pesticides, and β-lactam antibiotics. The process of its production is catalyzed by D-hydantoinase and D-carbamoylase in a two-step enzyme reaction. How to enhance the catalytic potential of the two enzymes is valuable for industrial application. In this investigation, an Escherichia coli strain genetically engineered with D-hydantoinase was immobilized by calcium alginate with certain adjuncts to evaluate the optimal condition for the biosynthesis of D-carbamoyl-p-hydroxyphenylglycine (D-CpHPG), the compound further be converted to D-hydroxyphenylglycine (D-HPG) by carbamoylase. Results: The optimal medium to produce D-CpHPG by whole-cell immobilization was a modified Luria-Bertani (LB) added with 3.0% (W/V) alginate, 1.5% (W/V) diatomite, 0.05% (W/V) CaCl2 and 1.00 mM MnCl2.The optimized diameter of immobilized beads for the whole-cell biosynthesis here was 2.60 mm. The maximized production rates of D-CpHPG were up to 76%, and the immobilized beads could be reused for 12 batches. Conclusions: This investigation not only provides an effective procedure for biological production of D-CpHPG, but gives an insight into the whole-cell immobilization technology.


Subject(s)
Escherichia coli , Amidohydrolases , Glycine/analogs & derivatives , Cells, Immobilized , Glycine/biosynthesis
8.
Acta Cir Bras ; 29(6): 359-64, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24919043

ABSTRACT

PURPOSE: To determine the role of mesenteric lymph reperfusion (MLR) on endotoxin translocation in brain to discuss the mechanism of brain injury subjected to superior mesenteric artery occlusion (SMAO) shock. METHODS: Twenty-four rats were randomly assigned to MLR, SMAO, MLR+SMAO and sham groups. MLR was performed by clamping the mesenteric lymph duct (MLD) for 1 h and then allowing reperfusion for 2 h in the MLR group; SMAO involved clamping the superior mesenteric artery (SMA) for 1 h, followed by reperfusion for 2 h in the SMAO group; occlusion of both the SMA and MLD for 1 h was followed by reperfusion for 2 h in the MLR+SMAO group rats. RESULTS: SMAO shock induced severe increased levels of the endotoxin, lipopolysaccharide receptor, lipopolysaccharide-binding protein, intercellular adhesion molecule-1 and tumor necrosis factor-α. Concurrently, MLR after SMAO shock further aggravates these deleterious effects. CONCLUSION: Mesenteric lymph reperfusion exacerbated the endotoxin translocation in brain; thereby increased inflammatory response occurred, suggesting that the intestinal lymph pathway plays an important role in the brain injury after superior mesenteric artery occlusion shock.


Subject(s)
Bacterial Translocation/physiology , Brain Injuries/etiology , Endotoxins/physiology , Lymphatic Vessels/physiology , Mesenteric Vascular Occlusion/physiopathology , Mesentery , Reperfusion Injury/physiopathology , Acute-Phase Proteins/analysis , Animals , Brain Injuries/metabolism , Carrier Proteins/analysis , Disease Models, Animal , Endotoxins/analysis , Enzyme-Linked Immunosorbent Assay , Intercellular Adhesion Molecule-1/analysis , Ligation , Lipopolysaccharide Receptors/analysis , Lymphatic Vessels/surgery , Male , Membrane Glycoproteins/analysis , Mesenteric Artery, Superior , Mesenteric Vascular Occlusion/complications , Random Allocation , Rats, Wistar , Reperfusion Injury/complications , Time Factors , Tumor Necrosis Factor-alpha/analysis
9.
Acta cir. bras ; Acta cir. bras;29(6): 359-364, 06/2014. graf
Article in English | LILACS | ID: lil-711592

ABSTRACT

PURPOSE: To determine the role of mesenteric lymph reperfusion (MLR) on endotoxin translocation in brain to discuss the mechanism of brain injury subjected to superior mesenteric artery occlusion (SMAO) shock. METHODS: Twenty-four rats were randomly assigned to MLR, SMAO, MLR+SMAO and sham groups. MLR was performed by clamping the mesenteric lymph duct (MLD) for 1 h and then allowing reperfusion for 2 h in the MLR group; SMAO involved clamping the superior mesenteric artery (SMA) for 1 h, followed by reperfusion for 2 h in the SMAO group; occlusion of both the SMA and MLD for 1 h was followed by reperfusion for 2 h in the MLR+SMAO group rats. RESULTS: SMAO shock induced severe increased levels of the endotoxin, lipopolysaccharide receptor, lipopolysaccharide-binding protein, intercellular adhesion molecule-1 and tumor necrosis factor-α. Concurrently, MLR after SMAO shock further aggravates these deleterious effects. CONCLUSION: Mesenteric lymph reperfusion exacerbated the endotoxin translocation in brain; thereby increased inflammatory response occurred, suggesting that the intestinal lymph pathway plays an important role in the brain injury after superior mesenteric artery occlusion shock. .


Subject(s)
Animals , Male , Bacterial Translocation/physiology , Brain Injuries/etiology , Endotoxins/physiology , Lymphatic Vessels/physiology , Mesentery , Mesenteric Vascular Occlusion/physiopathology , Reperfusion Injury/physiopathology , Acute-Phase Proteins/analysis , /analysis , Brain Injuries/metabolism , Carrier Proteins/analysis , Disease Models, Animal , Enzyme-Linked Immunosorbent Assay , Endotoxins/analysis , Intercellular Adhesion Molecule-1/analysis , Ligation , Lymphatic Vessels/surgery , Mesenteric Artery, Superior , Membrane Glycoproteins/analysis , Mesenteric Vascular Occlusion/complications , Random Allocation , Rats, Wistar , Reperfusion Injury/complications , Time Factors , Tumor Necrosis Factor-alpha/analysis
10.
Acta cir. bras. ; 29(6): 359-364, 06/2014. graf
Article in English | VETINDEX | ID: vti-10277

ABSTRACT

To determine the role of mesenteric lymph reperfusion (MLR) on endotoxin translocation in brain to discuss the mechanism of brain injury subjected to superior mesenteric artery occlusion (SMAO) shock. Twenty-four rats were randomly assigned to MLR, SMAO, MLR+SMAO and sham groups. MLR was performed by clamping the mesenteric lymph duct (MLD) for 1 h and then allowing reperfusion for 2 h in the MLR group; SMAO involved clamping the superior mesenteric artery (SMA) for 1 h, followed by reperfusion for 2 h in the SMAO group; occlusion of both the SMA and MLD for 1 h was followed by reperfusion for 2 h in the MLR+SMAO group rats. SMAO shock induced severe increased levels of the endotoxin, lipopolysaccharide receptor, lipopolysaccharide-binding protein, intercellular adhesion molecule-1 and tumor necrosis factor-α. Concurrently, MLR after SMAO shock further aggravates these deleterious effects. Mesenteric lymph reperfusion exacerbated the endotoxin translocation in brain; thereby increased inflammatory response occurred, suggesting that the intestinal lymph pathway plays an important role in the brain injury after superior mesenteric artery occlusion shock.(AU)


Subject(s)
Animals , Cerebrum/anatomy & histology , Arteries/anatomy & histology , Shock , Reperfusion , Rats/classification
11.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;46(1): 32-38, 11/jan. 2013. graf
Article in English | LILACS | ID: lil-665796

ABSTRACT

A recent study showed that miR-26a is downregulated in hepatocellular carcinoma tissues and that this downregulation is an independent predictor of survival. Interestingly, the same study also reported that miR-26a downregulation causes a concomitant elevation of IL-6 expression. Because miR-26a expression was found to be transcriptionally downregulated by oncogene c-Myc in various cancers, and the expression of c-Myc was increased by IL-6 stimulation, we hypothesized that IL-6 contributes to reduction of miR-26a in hepatocellular carcinoma. Serum IL-6 was measured by ELISA and miR-26a was detected by qRT-PCR. The data of 30 patients with hepatocellular carcinoma who had undergone surgical tumor resection revealed that serum IL-6 could be considered to be a predictor of survival up to 5 years for hepatocellular carcinoma patients (log-rank test, P < 0.05). We observed that the serum IL-6 concentration was inversely correlated with miR-26a expression in cancerous tissues (Pearson correlation test, r = -0.651, P < 0.01). Furthermore, by in vitro experiments with HepG2 cells, we showed that IL-6 stimulation can lead to miR-26a suppression via c-Myc activation, whereas in normal hepatocyte LO2 cells incubation with IL-6 had no significant effect on miR-26a expression. Taken together, these results indicate that miR-26a reduction in hepatocellular carcinoma might be due to IL-6 upregulation.


Subject(s)
Adult , Female , Humans , Male , Middle Aged , Carcinoma, Hepatocellular/metabolism , /metabolism , Liver Neoplasms/metabolism , MicroRNAs/metabolism , Case-Control Studies , Carcinoma, Hepatocellular/genetics , Gene Expression Regulation, Neoplastic , Immunohistochemistry , /genetics , Liver Neoplasms/genetics , MicroRNAs/genetics , MicroRNAs/physiology , Recurrence , Transcriptional Activation/genetics , Up-Regulation
12.
Braz J Med Biol Res ; 46(1): 32-8, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23011405

ABSTRACT

A recent study showed that miR-26a is downregulated in hepatocellular carcinoma tissues and that this downregulation is an independent predictor of survival. Interestingly, the same study also reported that miR-26a downregulation causes a concomitant elevation of IL-6 expression. Because miR-26a expression was found to be transcriptionally downregulated by oncogene c-Myc in various cancers, and the expression of c-Myc was increased by IL-6 stimulation, we hypothesized that IL-6 contributes to reduction of miR-26a in hepatocellular carcinoma. Serum IL-6 was measured by ELISA and miR-26a was detected by qRT-PCR. The data of 30 patients with hepatocellular carcinoma who had undergone surgical tumor resection revealed that serum IL-6 could be considered to be a predictor of survival up to 5 years for hepatocellular carcinoma patients (log-rank test, P < 0.05). We observed that the serum IL-6 concentration was inversely correlated with miR-26a expression in cancerous tissues (Pearson correlation test, r = -0.651, P < 0.01). Furthermore, by in vitro experiments with HepG2 cells, we showed that IL-6 stimulation can lead to miR-26a suppression via c-Myc activation, whereas in normal hepatocyte LO2 cells incubation with IL-6 had no significant effect on miR-26a expression. Taken together, these results indicate that miR-26a reduction in hepatocellular carcinoma might be due to IL-6 upregulation.


Subject(s)
Carcinoma, Hepatocellular/metabolism , Interleukin-6/metabolism , Liver Neoplasms/metabolism , MicroRNAs/metabolism , Adult , Carcinoma, Hepatocellular/genetics , Case-Control Studies , Female , Gene Expression Regulation, Neoplastic , Humans , Immunohistochemistry , Interleukin-6/genetics , Liver Neoplasms/genetics , Male , MicroRNAs/genetics , MicroRNAs/physiology , Middle Aged , Recurrence , Transcriptional Activation/genetics , Up-Regulation
13.
Clinics (Sao Paulo) ; 67(8): 901-6, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22948457

ABSTRACT

OBJECTIVES: Tumor-associated macrophages that generally exhibit an alternatively activated (M2) phenotype have been linked to tumor progression and metastasis. However, the role of M2-polarized macrophages in the growth and metastasis of lung adenocarcinoma remains enigmatic. The aim of this study was to explore the effect of M2 macrophages on the proliferation and migration of mouse Lewis lung carcinoma cells and tumor-induced lymphangiogenesis. METHODS: Trypan blue staining and the Transwell migration assay were performed to evaluate the effects of activated (M1 or M2) macrophages on the proliferation and migration of Lewis cells. Furthermore, vascular endothelial growth factor-C expression in Lewis cells and nitric oxide secretion from activated macrophages were detected during the co-culture assay. Following treatment with activated macrophages, lymphatic endothelial cells differentiated into capillary-like structures, and the induction of Lewis cell migration was assessed using a two-dimensional Matrigel-based assay. RESULTS: In the co-culture Transwell system, the proliferation and migration of Lewis cells were promoted by M2 macrophages. Moreover, the co-culture significantly increased the expression of vascular endothelial growth factor-C by Lewis cells and reduced the secretion of nitric oxide from M2 macrophages, which subsequently led to the capillary morphogenesis of lymphatic endothelial cells. Interestingly, following co-culture with Lewis cells, the function of RAW264.7 cells was polarized toward that of the M2 macrophage phenotype. CONCLUSION: M2-polarized macrophages promoted the metastatic behavior of Lewis cells by inducing vascular endothelial growth factor-C expression. Thus, the interruption of signaling between M2 macrophages and Lewis cells may be considered to be a new therapeutic strategy.


Subject(s)
Carcinoma, Lewis Lung/secondary , Lung Neoplasms/pathology , Macrophages/physiology , Vascular Endothelial Growth Factor C/metabolism , Animals , Carcinoma, Lewis Lung/metabolism , Cell Line, Tumor , Cell Migration Assays , Cell Movement , Cell Proliferation , Endothelial Cells/pathology , Lung Neoplasms/metabolism , Lymphangiogenesis/physiology , Macrophages/cytology , Mice , Time Factors , Vascular Endothelial Growth Factor C/physiology
14.
Clinics (Sao Paulo) ; 67(9): 1093-9, 2012 Sep.
Article in English | MEDLINE | ID: mdl-23018309

ABSTRACT

OBJECTIVE: Sorafenib is an oral multikinase inhibitor that has been proven effective as a single-agent therapy in hepatocellular carcinoma, and there is a strong rationale for investigating its use in combination with other agents. Vitamin K2 is nearly non-toxic to humans and has been shown to inhibit the growth of hepatocellular carcinoma. In this study, we evaluated the effects of a combination of sorafenib and vitamin K2 on the growth of hepatocellular carcinoma cells. METHODS: Flow cytometry, 3-(4,5-dimethyl-2-thiazolyl-2,5-diphenyl-2H-tetrazolium bromide) and nude mouse xenograft assays were used to examine the effects of sorafenib and vitamin K2 on the growth of hepatocellular carcinoma cells. Western blotting was used to elucidate the possible mechanisms underlying these effects. RESULTS: Assays for 3-(4,5-dimethyl-2-thiazolyl-2,5-diphenyl-2H-tetrazolium bromide) revealed a strong synergistic growth-inhibitory effect between sorafenib and vitamin K2. Flow cytometry showed an increase in cell cycle arrest and apoptosis after treatment with a combination of these two drugs at low concentrations. Sorafenib-mediated inhibition of extracellular signal-regulated kinase phosphorylation was promoted by vitamin K2, and downregulation of Mcl-1, which is required for sorafenib-induced apoptosis, was observed after combined treatment. Vitamin K2 also attenuated the downregulation of p21 expression induced by sorafenib, which may represent the mechanism by which vitamin K2 promotes the inhibitory effects of sorafenib on cell proliferation. Moreover, the combination of sorafenib and vitamin K2 significantly inhibited the growth of hepatocellular carcinoma xenografts in nude mice. CONCLUSIONS: Our results determined that combined treatment with sorafenib and vitamin K2 can work synergistically to inhibit the growth of hepatocellular carcinoma cells. This finding raises the possibility that this combined treatment strategy might be promising as a new therapy against hepatocellular carcinoma, especially for patients with poor liver tolerance.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Hepatocellular/drug therapy , Liver Neoplasms/drug therapy , Niacinamide/analogs & derivatives , Phenylurea Compounds/administration & dosage , Protein Kinase Inhibitors/administration & dosage , Vitamin K 2/administration & dosage , Animals , Blotting, Western , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Synergism , Flow Cytometry , Liver Neoplasms/pathology , Mice , Mice, Nude , Niacinamide/administration & dosage , Sorafenib , Time Factors , Treatment Outcome
15.
Clinics ; Clinics;67(9): 1093-1099, Sept. 2012. ilus
Article in English | LILACS | ID: lil-649391

ABSTRACT

OBJECTIVE: Sorafenib is an oral multikinase inhibitor that has been proven effective as a single-agent therapy in hepatocellular carcinoma, and there is a strong rationale for investigating its use in combination with other agents. Vitamin K2 is nearly non-toxic to humans and has been shown to inhibit the growth of hepatocellular carcinoma. In this study, we evaluated the effects of a combination of sorafenib and vitamin K2 on the growth of hepatocellular carcinoma cells. METHODS: Flow cytometry, 3-(4,5-dimethyl-2-thiazolyl-2,5-diphenyl-2H-tetrazolium bromide) and nude mouse xenograft assays were used to examine the effects of sorafenib and vitamin K2 on the growth of hepatocellular carcinoma cells. Western blotting was used to elucidate the possible mechanisms underlying these effects. RESULTS: Assays for 3-(4,5-dimethyl-2-thiazolyl-2,5-diphenyl-2H-tetrazolium bromide) revealed a strong synergistic growth-inhibitory effect between sorafenib and vitamin K2. Flow cytometry showed an increase in cell cycle arrest and apoptosis after treatment with a combination of these two drugs at low concentrations. Sorafenib-mediated inhibition of extracellular signal-regulated kinase phosphorylation was promoted by vitamin K2, and downregulation of Mcl-1, which is required for sorafenib-induced apoptosis, was observed after combined treatment. Vitamin K2 also attenuated the downregulation of p21 expression induced by sorafenib, which may represent the mechanism by which vitamin K2 promotes the inhibitory effects of sorafenib on cell proliferation. Moreover, the combination of sorafenib and vitamin K2 significantly inhibited the growth of hepatocellular carcinoma xenografts in nude mice. CONCLUSIONS: Our results determined that combined treatment with sorafenib and vitamin K2 can work synergistically to inhibit the growth of hepatocellular carcinoma cells. This finding raises the possibility that this combined treatment strategy might be promising as a new therapy against hepatocellular carcinoma, especially for patients with poor liver tolerance.


Subject(s)
Animals , Mice , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Hepatocellular/drug therapy , Liver Neoplasms/drug therapy , Niacinamide/analogs & derivatives , Phenylurea Compounds/administration & dosage , Protein Kinase Inhibitors/administration & dosage , /administration & dosage , Blotting, Western , Cell Line, Tumor , Carcinoma, Hepatocellular/pathology , Cell Proliferation/drug effects , Drug Synergism , Flow Cytometry , Liver Neoplasms/pathology , Mice, Nude , Niacinamide/administration & dosage , Time Factors , Treatment Outcome
16.
Clinics ; Clinics;67(8): 901-906, Aug. 2012. ilus, graf
Article in English | LILACS | ID: lil-647793

ABSTRACT

OBJECTIVES: Tumor-associated macrophages that generally exhibit an alternatively activated (M2) phenotype have been linked to tumor progression and metastasis. However, the role of M2-polarized macrophages in the growth and metastasis of lung adenocarcinoma remains enigmatic. The aim of this study was to explore the effect of M2 macrophages on the proliferation and migration of mouse Lewis lung carcinoma cells and tumor-induced lymphangiogenesis. METHODS: Trypan blue staining and the Transwell migration assay were performed to evaluate the effects of activated (M1 or M2) macrophages on the proliferation and migration of Lewis cells. Furthermore, vascular endothelial growth factor-C expression in Lewis cells and nitric oxide secretion from activated macrophages were detected during the co-culture assay. Following treatment with activated macrophages, lymphatic endothelial cells differentiated into capillary-like structures, and the induction of Lewis cell migration was assessed using a twodimensional Matrigel-based assay. RESULTS: In the co-culture Transwell system, the proliferation and migration of Lewis cells were promoted by M2 macrophages. Moreover, the co-culture significantly increased the expression of vascular endothelial growth factor-C by Lewis cells and reduced the secretion of nitric oxide from M2 macrophages, which subsequently led to the capillary morphogenesis of lymphatic endothelial cells. Interestingly, following co-culture with Lewis cells, the function of RAW264.7 cells was polarized toward that of the M2 macrophage phenotype. CONCLUSION: M2-polarized macrophages promoted the metastatic behavior of Lewis cells by inducing vascular endothelial growth factor-C expression. Thus, the interruption of signaling between M2 macrophages and Lewis cells may be considered to be a new therapeutic strategy.


Subject(s)
Animals , Mice , Carcinoma, Lewis Lung/secondary , Lung Neoplasms/pathology , Macrophages/physiology , Vascular Endothelial Growth Factor C/metabolism , Cell Line, Tumor , Cell Migration Assays , Cell Movement , Cell Proliferation , Carcinoma, Lewis Lung/metabolism , Endothelial Cells/pathology , Lung Neoplasms/metabolism , Lymphangiogenesis/physiology , Macrophages/cytology , Time Factors , Vascular Endothelial Growth Factor C/physiology
17.
Environ Sci Technol ; 45(3): 1082-7, 2011 Feb 01.
Article in English | MEDLINE | ID: mdl-21174467

ABSTRACT

This report shows, for the first time, the effectiveness of the phytohormone kinetin (KN) in increasing Cr translocation from roots to stems in Mexican Palo Verde. Fifteen-day-old seedlings, germinated in soil spiked with Cr(III) and (VI) at 60 and 10 mg kg(-1), respectively, were watered every other day for 30 days with a KN solution at 250 µM. Samples were analyzed for catalase (CAT) and ascorbate peroxidase (APOX) activities, Cr concentration, and Cr distribution in tissues. Results showed that KN reduced CAT but increased APOX in the roots of Cr(VI)-treated plants. In the leaves, KN reduced both CAT and APOX in Cr(III) but not in Cr(VI)-treated plants. However, KN increased total Cr concentration in roots, stems, and leaves by 45%, 103%, and 72%, respectively, compared to Cr(III) alone. For Cr(VI), KN increased Cr concentrations in roots, stems, and leaves, respectively, by 53%, 129%, and 168%, compared to Cr(VI) alone. The electron probe microanalyzer results showed that Cr was mainly located at the cortex section in the root, and Cr distribution was essentially homogeneous in stems. However, proven through X-ray images, Cr(VI)-treated roots and stems had more Cr accumulation than Cr(III) counterparts. KN increased the Cr translocation from roots to stems.


Subject(s)
Catalase/metabolism , Chromium/metabolism , Fabaceae/metabolism , Kinetin/metabolism , Peroxidases/metabolism , Soil Pollutants/metabolism , Ascorbate Peroxidases , Biodegradation, Environmental , Chromium/chemistry , Fabaceae/chemistry , Fabaceae/growth & development , Plant Roots/chemistry , Plant Roots/growth & development , Plant Roots/metabolism , Seedlings/chemistry , Seedlings/growth & development , Seedlings/metabolism , Soil/chemistry , Soil Pollutants/chemistry
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