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2.
Zhonghua Yi Xue Za Zhi ; 99(10): 758-763, 2019 Mar 12.
Artigo em Chinês | MEDLINE | ID: mdl-30884630

RESUMO

Objective: To investigate the risk factors of systemic inflammatory response syndrome (SIRS) in patients undergoing flexible ureteroscopic lithotripsy based on enhanced recovery after surgery (ERAS). Methods: The clinical data of 243 kidney stone cases who underwent flexible ureteroscopic lithotripsy based on ERAS in the First Affiliated Hospital of Wannan Medical College from January 2016 to December 2017 were analyzed retrospectively. The cases were divided into two groups according to whether they had SIRS after surgery: SIRS group (26 cases) and non-SIRS group (217 cases). The age, gender, laterality of kidney stone, history of previous kidney stone surgery, degree of hydronephrosis, multiple kidney stones, length of operation time, white blood cell count of preoperative urine routine, result of preoperative urine culture, use of preoperative antibiotics, diabetes and other chronic diseases in the groups were collected and analyzed. Results: SIRS occurred in 26 cases in this study, which accounted for 10.7% (26/243). Multivariate analysis found that, moderate and severe hydronephrosis (OR=6.711, P=0.008), stone burden ≥2 cm (OR=10.353, P<0.001), length of operation time ≥ 60 min (OR=5.583, P=0.011), white blood cell count of preoperative urine routine ≥25×10(6)/L (OR=6.195, P=0.005), positive preoperative urine culture (OR=4.216, P=0.011), diabetes and other chronic diseases (OR=4.532, P=0.006) were the independent risk factors for postoperative SIRS (P<0.05). Conclusions: The occurrence of SIRS after flexible ureteroscopic lithotripsy based on ERAS is closely correlated with hydronephrosis, stone burden, length of operation time, white blood cell count of preoperative urine routine, positive preoperative urine culture, diabetes and other chronic diseases.


Assuntos
Litotripsia , Síndrome de Resposta Inflamatória Sistêmica , Humanos , Cálculos Renais , Estudos Retrospectivos , Fatores de Risco , Ureteroscopia
3.
J Biol Regul Homeost Agents ; 29(4): 881-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26753652

RESUMO

Osteosarcoma represents an aggressive type of bone malignancy that poses a significant health threat. The objective of the current study was to analyze the effect and mechanism of dihydroartemisinin (DHA) on the proliferation, metastasis and apoptosis of human osteosarcoma cells. A gradient concentration of DHA (15, 25 and 35 µmol.L-1) was used to stimulate the cells, along with control and Dimethyl sulfoxide (DMSO). The phenotypic outcomes were characterized using MTT assay, clone formation assay, Hoechst 33258 staining assay, luciferase reporter plasmid assay, Western blot and wound healing assay. In addition, IBM SPSS Statistics 18.0 software was applied for statistical analysis and all experimental data were expressed as mean ± s.d. Analysis of variance (ANOVA) was applied to compare the differences among multiple groups. Our results demonstrated that DHA inhibited the proliferation and metastasis of osteosarcoma cells and promoted the apoptosis in the cytomorphosis.


Assuntos
Apoptose/efeitos dos fármacos , Artemisininas/farmacologia , Neoplasias Ósseas/tratamento farmacológico , Osteossarcoma/tratamento farmacológico , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Osteossarcoma/patologia , Osteossarcoma/secundário
4.
Commun Theor Phys ; 49(5): 1073-1090, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21949462

RESUMO

The evolutionary dynamics first conceived by Darwin and Wallace, referring to as Darwinian dynamics in the present paper, has been found to be universally valid in biology. The statistical mechanics and thermodynamics, while enormous successful in physics, have been in an awkward situation of wanting a consistent dynamical understanding. Here we present from a formal point of view an exploration of the connection between thermodynamics and Darwinian dynamics and a few related topics. We first show that the stochasticity in Darwinian dynamics implies the existence temperature, hence the canonical distribution of Boltzmann-Gibbs type. In term of relative entropy the Second Law of thermodynamics is dynamically demonstrated without detailed balance condition, and is valid regardless of size of the system. In particular, the dynamical component responsible for breaking detailed balance condition does not contribute to the change of the relative entropy. Two types of stochastic dynamical equalities of current interest are explicitly discussed in the present approach: One is based on Feynman-Kac formula and another is a generalization of Einstein relation. Both are directly accessible to experimental tests. Our demonstration indicates that Darwinian dynamics represents logically a simple and straightforward starting point for statistical mechanics and thermodynamics and is complementary to and consistent with conservative dynamics that dominates the physical sciences. Present exploration suggests the existence of a unified stochastic dynamical framework both near and far from equilibrium.

5.
IEEE Trans Pattern Anal Mach Intell ; 40(8): 1918-1931, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-28796609

RESUMO

The article describes a pipeline that receives as input a sequence of stereo images, and outputs the camera motion and a Piecewise-Planar Reconstruction (PPR) of the scene. The pipeline, named Piecewise-Planar StereoScan (PPSS), works as follows: the planes in the scene are detected for each stereo view using semi-dense depth estimation; the relative pose is computed by a new closed-form minimal algorithm that only uses point correspondences whenever plane detections do not fully constrain the motion; the camera motion and the PPR are jointly refined by alternating between discrete optimization and continuous bundle adjustment; and, finally, the detected 3D planes are segmented in images using a new framework that handles low texture and visibility issues. PPSS is extensively validated in indoor and outdoor datasets, and benchmarked against two popular point-based SfM pipelines. The experiments confirm that plane-based visual odometry is resilient to situations of small image overlap, poor texture, specularity, and perceptual aliasing where the fast LIBVISO2 [1] pipeline fails. The comparison against VisualSfM+CMVS/PMVS [2] , [3] shows that, for a similar computational complexity, PPSS is more accurate and provides much more compelling and visually pleasant 3D models. These results strongly suggest that plane primitives are an advantageous alternative to point correspondences for applications of SfM and 3D reconstruction in man-made environments.

6.
Mol Immunol ; 35(5): 279-91, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9747888

RESUMO

Previous analyses of the T-cell receptor (TCR) repertoire utilized in response to the 1-102 fragment of the lambda cI repressor protein and specific for the immunodominant amino acid 12-26 region in the context of I-Ek, have shown this repertoire to be extremely restricted. In contrast, here we show that the TCR repertoires utilized in two strains of I-Ek expressing mice in response to two linear peptides representing this immunodominant region are diverse. Despite their extensive diversity, these repertoires are somewhat overlapping. In addition, structural similarities were observed between the full lambda cI fragment (1-102) and peptide elicited TCR repertoires, including frequent use of the Valpha2 family of gene segments, particularly among peptide (12-26) elicited TCRs cross-reactive with 1-102/I-Ek. Nevertheless, these data indicate that it may be difficult to mimic the immune response to an immunodominant epitope of a protein antigen via immunization with linear peptides containing the amino acid sequence of that epitope. Possible explanations for differences in the levels of TCR diversity among T cells responding to an epitope present in a nominal antigen as compared to T cells responding to linear peptide antigens containing this same epitope are discussed.


Assuntos
Epitopos de Linfócito T/metabolismo , Antígenos de Histocompatibilidade Classe II/genética , Epitopos Imunodominantes/imunologia , Peptídeos/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Epitopos de Linfócito T/biossíntese , Epitopos de Linfócito T/genética , Regulação da Expressão Gênica/imunologia , Rearranjo Gênico da Cadeia alfa dos Receptores de Antígenos dos Linfócitos T , Rearranjo Gênico da Cadeia beta dos Receptores de Antígenos dos Linfócitos T , Antígenos de Histocompatibilidade Classe II/imunologia , Hibridomas/metabolismo , Epitopos Imunodominantes/biossíntese , Epitopos Imunodominantes/genética , Camundongos , Camundongos Endogâmicos A , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Peptídeos/genética , Peptídeos/metabolismo , Receptores de Antígenos de Linfócitos T/biossíntese , Receptores de Antígenos de Linfócitos T/genética
7.
Funct Integr Genomics ; 4(3): 188-95, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-14762706

RESUMO

The biology and behavior of bacteriophage lambda regulation have been the focus of classical investigations of molecular control of gene expression. Both qualitative and quantitative aspects of this behavior have been systematically characterized experimentally. Complete understanding of the robustness and stability of the genetic circuitry for the lysis-lysogeny switch remains an unsolved puzzle. It is an excellent test case for our understanding of biological behavior of an integrated network based on its physical, chemical, DNA, protein, and functional properties. We have used a new approach to non-linear dynamics to formulate a new mathematical model, performed a theoretical study on the phage lambda life cycle, and solved the crucial part of this puzzle. We find a good quantitative agreement between the theoretical calculation and published experimental observations in the protein number levels, the lysis frequency in the lysogen culture, and the lysogenization frequency for mutants of O(R). We also predict the desired robustness for the lambda genetic switch. We believe that this is the first successful example in the quantitative calculation of robustness and stability of the phage lambda regulatory network, one of the simplest and most well-studied regulatory systems.


Assuntos
Bacteriófago lambda/genética , Bacteriófago lambda/fisiologia , Epigênese Genética , Redes Reguladoras de Genes , Lisogenia/genética , Modelos Genéticos , Dinâmica não Linear , Regiões Operadoras Genéticas , Regiões Promotoras Genéticas , Processos Estocásticos
8.
J Bioinform Comput Biol ; 2(4): 785-817, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15617166

RESUMO

Based on the dynamical structure theory for complex networks recently developed by one of us and on the physical-chemical models for gene regulation, developed by Shea and Ackers in the 1980's, we formulate a direct and concise mathematical framework for the genetic switch controlling phage lambda life cycles, which naturally includes the stochastic effect. The dynamical structure theory states that the dynamics of a complex network is determined by its four elementary components: The dissipation (analogous to degradation), the stochastic force, the driving force determined by a potential, and the transverse force. The potential may be interpreted as a landscape for the phage development in terms of attractive basins, saddle points, peaks and valleys. The dissipation gives rise to the adaptivity of the phage in the landscape defined by the potential: The phage always has the tendency to approach the bottom of the nearby attractive basin. The transverse force tends to keep the network on the equal-potential contour of the landscape. The stochastic fluctuation gives the phage the ability to search around the potential landscape by passing through saddle points. With molecular parameters in our model fixed primarily by the experimental data on wild-type phage and supplemented by data on one mutant, our calculated results on mutants agree quantitatively with the available experimental observations on other mutants for protein number, lysogenization frequency, and a lysis frequency in lysogen culture. The calculation reproduces the observed robustness of the phage lambda genetic switch. This is the first mathematical description that successfully represents such a wide variety of major experimental phenomena. Specifically, we find: (1) The explanation for both the stability and the efficiency of phage lambda genetic switch is the exponential dependence of saddle point crossing rate on potential barrier height, a result of the stochastic motion in a landscape; and (2) The positive feedback of cI repressor gene transcription, enhanced by the CI dimer cooperative binding, is the key to the robustness of the phage lambda genetic switch against mutations and fluctuations in kinetic parameter values.


Assuntos
Bacteriófago lambda/genética , Proteínas de Ligação a DNA/genética , Regulação Viral da Expressão Gênica/genética , Genes de Troca/genética , Lisogenia/genética , Modelos Genéticos , Proteínas Virais/genética , Simulação por Computador , Instabilidade Genômica/genética , Modelos Estatísticos , Proteínas Repressoras/genética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Phys Rev Lett ; 85(8): 1626-9, 2000 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-10970574

RESUMO

The control of time evolution of a quantum state under various physical constraints is investigated and solved in the context of a two-level system. We have discovered a general scheme of steering an eigenenergy state to a destination without net nonadiabatic transitions, and we discuss how the result may be tested and utilized in practice.

10.
Int Angiol ; 14(4): 375-80, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8708430

RESUMO

OBJECTIVE: Intimal hyperplasia (IH) is a significant cause of late prosthetic graft occlusion. The influence of heparin and low molecular weight heparin (LMWH) on IH was studied in a sheep model. EXPERIMENTAL DESIGN: A gelatin sealed Dacron (Gelsoft) interposition vascular graft was placed end to end in sheep carotid artery. Standard heparin (SH) was administered in a dose of 7,500 units twice daily subcutaneously (n = 6). LMWH (enoxaparin) was administered in two dosages, a "low dose" of 2 mg/kg (n = 6) and a "high dose" of 5 mg/kg (n = 6) subcutaneously daily. A control group received a graft but no heparin (n = 6). At one month the animals were sacrificed and the grafts sectioned. An intimal measurement was obtained under light microscopy using an eyepiece graticule from a longitudinally sectioned graft. RESULTS: Controls occluded five grafts of six and recorded a mean intimal thickness of 2,510 micrometres, SH sheep occluded two with a mean thickness of 83 (p < 0.05), low dose enoxaparin sheep had no occlusions with a mean thickness of 73 (p < 0.001) and high dose enoxaparin sheep occluded one with a mean thickness of 225 (p < 0.01). The reduced occlusion rates were significant for the LMWH groups (p = 0.007 for low dose, p = 0.04 for high dose) but not for SH. There were no significant differences between treatment groups with respect to IH. CONCLUSIONS: In this sheep animal study, each of SH and two LMWH dose regimens resulted in a reduction in Dacron vascular graft occlusion rate and the development of IH, with the greatest effect seen in the low dose LMWH group.


Assuntos
Anticoagulantes/uso terapêutico , Oclusão de Enxerto Vascular/prevenção & controle , Heparina de Baixo Peso Molecular/uso terapêutico , Heparina/uso terapêutico , Túnica Íntima/efeitos dos fármacos , Animais , Anticoagulantes/administração & dosagem , Artérias Carótidas/efeitos dos fármacos , Artérias Carótidas/cirurgia , Divisão Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Heparina/administração & dosagem , Heparina de Baixo Peso Molecular/administração & dosagem , Hiperplasia/patologia , Hiperplasia/prevenção & controle , Infusões Intravenosas , Ovinos , Tempo de Trombina , Túnica Íntima/patologia
11.
Int Angiol ; 18(2): 131-9, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10424369

RESUMO

BACKGROUND: Both unfractionated heparin (UH) and low molecular weight heparin (LMWH) in therapeutic anticoagulant doses have been shown to inhibit the development of intimal hyperplasia (IH) but with an increased risk of haemorrhage. In this study we investigated the effect of a "low dose" and "high dose" of UH and LMWH on the inhibition of IH together with their effect on plasma anti-Xa activity (AXa) and activated partial thromboplastin time (APTT) using a carotid artery sheep model. METHODS: A gelatin sealed Dacron patch graft was implanted into the common carotid artery of sheep which were randomly allocated to a control group (Group 1, n=10) or to one of four treatment groups receiving either low-dose LMWH enoxaparin 1 mg/kg/day (group 2, n=11), high-dose LMWH enoxaparin 2 mg/kg/day (Group 3, n=13), low-dose UH 125 u/kg/day (Group 4, n=10) or high-dose UH 250 u/kg/day (Group 5, n=10). The LMWH was administered subcutaneously once daily for four weeks and the UH in two divided doses per day for four weeks. During the treatment period, AXa and APTT were assayed from blood collected prior to and at 1 and 2 h after heparin administration on day 3, 7, 14, 21 and 28. On day 28, all animals were sacrificed and grafts were collected for analysis after taking blood samples prior to, then at 0.5, 1, 2, 3, 4, 6, 8, 12 and 24 h following the last injection. Measurements of intimal thickness were obtained under light microscopy from eight transverse sections of each grafted artery using an eyepiece graticule. RESULTS: IH measurements (Mean+/-SD) were: Group 1 (controls) 288+/-86 microm, Group 2 (low-dose LMWH) 222+/-50 mm (p<0.05 compared to Group 1), Group 3 (high-dose LMWH) 203+/-78 microm (p<0.01), Group 4 (low-dose UH) 275+/-61 microm, and Group 5 (high-dose UH) 206+/-71 microm (p<0.01). There was no significant difference between Groups 2, 3 and 5. Groups 2, 3 and 5 demonstrated significant AXa during the 28 days period of which Groups 2 and 5 showed a significant increase in AXa levels with time. In the 24 h study after the last dose of treatment both Groups 2 and 3 showed longer AXa than group 5 (12-24 h vs 8 h). When compared to the control group, significant elevation of APTT was demonstrated in Groups 3 and 5. Group 5 had significantly longer APTT than Group 3. In the 24 h study, APTT reflected the changes of AXa in all groups. CONCLUSIONS: In this study the LMWH enoxaparin was effective in reducing the formation of IH both at a standard anticoagulant therapeutic dose of 2 mg/kg/day and also at a lower dose of 1 mg/kg/day.


Assuntos
Heparina de Baixo Peso Molecular/administração & dosagem , Heparina/administração & dosagem , Doenças dos Ovinos/prevenção & controle , Túnica Íntima/patologia , Animais , Anticorpos/sangue , Fator Xa/imunologia , Feminino , Heparina/uso terapêutico , Heparina de Baixo Peso Molecular/uso terapêutico , Hiperplasia/prevenção & controle , Tempo de Tromboplastina Parcial , Ovinos , Túnica Íntima/efeitos dos fármacos , Cicatrização
12.
Int Angiol ; 18(3): 225-32, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10688422

RESUMO

BACKGROUND: The aim of this study was to treat methicillin-resistant Staphylococcus aureus (MRSA) or S. epidermidis prosthetic vascular graft infections by in situ replacement with a rifampicin bonded Gelsoft graft. METHODS: Interposition grafts were placed in the internal carotid artery of 56 merino sheep and the graft surface directly inoculated with 10(8) colony forming units (CFU) of MRSA (29) or S. epidermidis (27). At three weeks, grafts were harvested and sheep allocated to three groups. In the MRSA infected group, sheep received grafts soaked in 1.2 mg/ml (12), 10 mg/ml (10) and no (7) rifampicin. For S. epidermidis, sheep received grafts soaked in 1.2 mg/ml (10), 10 mg/ml (9) and no (8) rifampicin. There were two deaths, in the MRSA study group, one each from the rifampicin treated groups. The remaining sheep were euthanased and grafts harvested three weeks following regrafting. Grafts at harvests were assessed for perigraft abscess formation, anastomotic disruption and graft thrombosis. Swabs were taken to assess bacterial growth in the perigraft tissues, and external and internal graft surfaces. A 3-5 mm segment of graft was incubated in a broth medium. For S. epidermidis the remainder of the graft was ground and then incubated in a broth medium. RESULTS: For MRSA, no statistical difference between the groups was reached for any of the measured parameters. For S. epidermidis, a significant reduction was reached for total infected specimens in the 10 mg/ml group compared to both control (p<0.001) and 1.2 mg/ml (p<0.005) groups. Graft reinfection was also less likely to occur with S. epidermidis than MRSA. CONCLUSIONS: In conclusion, replacement of S. epidermidis infected vascular grafts with 10 mg/ml rifampicin soaked Gelsoft graft is effective in reducing subsequent S. epidermidis infection. This conclusion cannot be extended to MRSA infected vascular grafts.


Assuntos
Implante de Prótese Vascular , Prótese Vascular/efeitos adversos , Polietilenotereftalatos , Infecções Relacionadas à Prótese/prevenção & controle , Rifampina/administração & dosagem , Infecções Estafilocócicas/prevenção & controle , Animais , Prótese Vascular/microbiologia , Artéria Carótida Primitiva/microbiologia , Artéria Carótida Primitiva/cirurgia , Feminino , Gelatina , Resistência a Meticilina , Ovinos , Staphylococcus aureus , Staphylococcus epidermidis
13.
Int Angiol ; 19(2): 158-65, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10905800

RESUMO

BACKGROUND: The aim of this study was to treat methicillin-resistant Staphylococcus aureus (MRSA) or S. epidermidis prosthetic vascular graft infections by in situ replacement with a rifampicin bonded Gelsoft graft. METHODS: Interposition grafts were placed in the carotid artery of 56 sheep and the graft surface directly inoculated with 10(8) colony forming units of MRSA or S. epidermidis. At three weeks, grafts were harvested and sheep allocated to three groups. In the MRSA group, sheep received grafts soaked in 1.2 mg/ml (12), 10 mg/ml (10) and no rifampicin (7). For S. epidermidis, sheep received grafts soaked in 1.2 mg/ml (10), 10 mg/ml (9) and no rifampicin (8). There were two deaths, in the MRSA study group. Remaining sheep were euthanased and grafts harvested three weeks following regrafting. Swabs were taken to assess bacterial growth in the perigraft tissues, and external and internal graft surfaces. A 3-5 mm segment of graft was incubated in broth medium. RESULTS: For MRSA, no statistical difference between the groups was reached for any of the measured parameters. For S. epidermidis, a significant reduction was reached for total infected specimens in the 10 mg/ml group compared to both control (p<0.001) and 1.2 mg/ml (p<0.005) groups. Graft re-infection was also less likely to occur with S. epidermidis than MRSA. CONCLUSIONS: Replacement of S. epidermidis infected vascular grafts with 10 mg/ml rifampicin soaked Gelsoft graft is effective in reducing subsequent S. epidermidis infection. This conclusion cannot be extended to MRSA infected vascular grafts.


Assuntos
Prótese Vascular/efeitos adversos , Infecções Relacionadas à Prótese/prevenção & controle , Infecções Relacionadas à Prótese/cirurgia , Rifampina/administração & dosagem , Infecções Estafilocócicas/cirurgia , Animais , Implante de Prótese Vascular , Artéria Carótida Primitiva/cirurgia , Feminino , Gelatina , Resistência a Meticilina , Polietilenotereftalatos , Desenho de Prótese , Reoperação , Ovinos , Staphylococcus epidermidis
14.
Int Angiol ; 16(2): 94-100, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9257669

RESUMO

BACKGROUND: A Dacron patch graft was placed in the common carotid artery of sheep to assess the effect of three different doses of unfractionated heparin administered for periods of one to four weeks. MATERIALS AND METHODS: Animals were divided into a control group (n=6) in which animals received a patch graft but no heparin and three main treatment groups on the basis of the dose of heparin received. Group 1 animals (n=24) received 140 units per kg daily in two divided doses. Group 2 (n=24) received 280 units per kg daily and Group 3 (n=24) received 420 units per kg daily. Each treatment group was further divided into four subgroups on the basis of the duration of treatment. Groups 1(i), 2(i), 3(i) had treatment for one week. Groups 1(ii), 2(ii), 3(ii) had treatment for two weeks. Groups 1(iii), 2(iii), 3(iii) had treatment for three weeks. Groups 1(iv), 2(iv), 3(iv) had treatment for four weeks. There were six animals in each subgroup giving a total of 72 treated sheep. Animals were sacrificed at four weeks and an intimal measurement in pm was obtained under light microscopy from a transverse sectioned segment of artery containing the patch graft using an eyepiece graticule. RESULTS: There were no haemorrhagic complications. Control animals had a mean intimal thickness of 176 pm. All treatment groups had significantly less IH--Group 1 131.9 (p<0.01), Group 2 138.5 (p<0.05), Group 3 117.8 (p<0.01). There were no significant differences between the treatment groups. There was significantly less IH in animals treated for four weeks (106.3) compared to one week (140.2, p<0.05). CONCLUSIONS: This study indicates that inhibition of IH can be achieved by heparin with optimal effect from a four week treatment period.


Assuntos
Prótese Vascular , Artéria Carótida Primitiva/patologia , Heparina/administração & dosagem , Túnica Íntima/patologia , Animais , Artéria Carótida Primitiva/efeitos dos fármacos , Artéria Carótida Primitiva/cirurgia , Esquema de Medicação , Heparina/farmacologia , Hiperplasia/prevenção & controle , Polietilenotereftalatos , Ovinos , Fatores de Tempo , Túnica Íntima/efeitos dos fármacos
15.
Biol Trace Elem Res ; 15: 243-55, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-2484522

RESUMO

Aberrant differentiation is a frequent hallmark of tumors, suggesting that modulators for differentiation and proliferation play a role in multistage carcinogenesis and that their use can also be exploited in cancer chemoprevention and therapy. We have demonstrated that selenium (Se) may be a modulator for the differentiation and proliferation of tumor cells. Evidence has been obtained that Se exerts the following effects: reversing changes of biochemical phenotypes toward normal levels, including reduction of cGMP level and cAMP-dependent protein kinase isozyme type I; increase in cAMP level and cAMP-dependent protein kinase isozyme type II, and altering membrane properties. Furthermore, we have obtained support for this hypothesis utilizing experiments on cultured human liver cell lines. It is demonstrated that Se can lead to the following changes: a. reduction of mitotic index; b. increase in the adhesiveness of cells; c. decrease in confluent saturation density and induction of an early contact inhibition; and d. decrease in tumorigenicity. For the purpose of comparison, the effects of Se on the normal counterparts was also studied. Contrary to what was observed above, there was no significant change in both biochemical and cellular aspects of normal cells treated analogously.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Selênio/farmacologia , Animais , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Humanos , Isoenzimas/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Masculino , Fluidez de Membrana/efeitos dos fármacos , Camundongos , Índice Mitótico/efeitos dos fármacos , Transplante de Neoplasias , Proteínas Quinases/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Células Tumorais Cultivadas
16.
Zhonghua Zhong Liu Za Zhi ; 9(6): 408-11, 22, 1987 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-3452535

RESUMO

After treating human lung adenocarcinoma cells by Na2SeO3 (1 microgram/ml) for 24 hours, its mitotic index decreased by 50%. The reduction rate was directly proportional to selenite concentration (1-5 micrograms/ml). In the meantime, the labelling index, growth rate and progression of the cell cycle were also inhibited. In contrast to the above observation, there was no marked change in the cell count, mitotic index, labelling index and the average silver granule number in the human embryonic lung diploid cells treated by Na2SeO3 (1-5 micrograms/ml) for 1-3 days. When human embryonic lung diploid cells were mix-cultured with human lung adenocarcinoma cells in the presence of 5 micrograms/ml Na2SeO3 for 24 hours, the former maintained a normal morphology, while the lung cancer cells showed heavily vacuolated cytoplasms and distorted nuclei.


Assuntos
Adenocarcinoma/patologia , Neoplasias Pulmonares/patologia , Selênio/farmacologia , Ciclo Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feto , Fibroblastos/efeitos dos fármacos , Humanos , Pulmão/citologia , Ácido Selenioso , Células Tumorais Cultivadas/efeitos dos fármacos
17.
Zhonghua Zhong Liu Za Zhi ; 9(2): 90-4, 1987 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-3477417

RESUMO

The cytogenetic studies on three esophageal cancer cell lines established in China were done. Thirty metaphases showing suitable chromosome length and good G-banding pattern from each of the cell lines were chosen and subjected to karyological analysis. The typical karyotypes from these cell lines were listed, and the variation of chromosome number as well as the morphological characteristics, possible sources and the incidence of the marker chromosomes were analysed. Eca 109 is the cell line first established and used extensively in China. A strictly regular karyotype pattern was found in it: the modal number of chromosomes being 63-64; the number of each type of chromosome varying between 1-5; a distal deletion of short arm of chromosome No. 1 being discernible in all metaphases, with break sites located within 1p22-1p33. Also a distal deletion of long arm of chromosome No. 4 was usually visible. There were seven marker chromosomes with high incidence. Among them, M1 marker chromosome was a large subacrocentric chromosome which was observed in the early passages of this cell line. The chromosome number of Ec 17 cell line was usually subtetraploid. In addition to the numerical variation in some of the chromosomes, six marker chromosomes were usually observed. Among them, M1 involved reciprocal translocation between chromosome No. 1 and No. 4. M3 of Ec 17 was in correspondence with M5 of Eca 109. Both were Rob (13q;14q). The chromosome number of Ec 56 was usually subtetraploid, and in addition to the numerical variation in some of the chromosomes, seven marker chromosomes were usually observed.


Assuntos
Aberrações Cromossômicas , Neoplasias Esofágicas/genética , Linhagem Celular , Bandeamento Cromossômico , Marcadores Genéticos , Humanos , Cariotipagem , Poliploidia
18.
Zhongguo Zhong Yao Za Zhi ; 23(1): 42-3, 63, 1998 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-11243157

RESUMO

Pepper roots contain 0.39% of essential oil. By GC-MS method, 44 peaks and 22 compounds were obtained and identified. The major component was trans-caryophyllene. The trace metal content analysis showed that the heavy metals were under the safety level.


Assuntos
Medicamentos de Ervas Chinesas/química , Óleos Voláteis/isolamento & purificação , Plantas Medicinais/química , Sesquiterpenos/isolamento & purificação , Oligoelementos/análise , Cromatografia Gasosa-Espectrometria de Massas , Magnoliopsida/química , Óleos Voláteis/química , Raízes de Plantas/química , Sesquiterpenos Policíclicos , Sesquiterpenos/química
19.
Zhongguo Zhong Yao Za Zhi ; 26(3): 182-5, 2001 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-12525038

RESUMO

OBJECTIVE: To analyze the constituents from the rhizomes of Atractylodes lancea and A. chinensis in essential oils. METHOD: GC-MS method was used. RESULT: 32 and 29 compounds were identified respectively. CONCLUSION: The main constituents in the essential oils from the rhizome of A. chinensis are beta-eudesmol or a mixture of beta-eudesmol and atractylone, whereas from that of A. lancea are hinesol, a mixture of beta-eudesmol and atractylone, and atractylone.


Assuntos
Atractylodes/química , Óleos Voláteis/química , Plantas Medicinais/química , Sesquiterpenos de Eudesmano , Compostos de Espiro/isolamento & purificação , Terpenos/isolamento & purificação , Atractylodes/classificação , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis/isolamento & purificação , Raízes de Plantas/química , Plantas Medicinais/classificação , Sesquiterpenos
20.
Interdiscip Sci ; 2(2): 140-4, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20640781

RESUMO

Based on an innovative endogenous network hypothesis on cancer genesis and progression we have been working towards a quantitative cancer theory along the systems biology perspective. Here we give a brief report on our progress and illustrate that combing ideas from evolutionary and molecular biology, mathematics, engineering, and physics, such quantitative approach is feasible.


Assuntos
Biologia Computacional/métodos , Neoplasias/metabolismo , Neoplasias/patologia , Algoritmos , Simulação por Computador , Progressão da Doença , Evolução Molecular , Humanos , Teoria da Informação , Masculino , Modelos Teóricos , Dinâmica não Linear , Neoplasias da Próstata/patologia , Processos Estocásticos , Biologia de Sistemas
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