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1.
Int J Clin Pediatr Dent ; 13(Suppl 1): S82-S86, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-34434019

RESUMEN

AIM: This study aimed to study the intensity and duration of patients' pain perception after placement of elastomeric separators and the effects of various methods to reduce the pain. MATERIALS AND METHODS: Elastomeric separators were placed on either side of first molars in 120 patients which were divided into 4 groups. Patients in group I were control group, group II underwent low-level LASER therapy, group III were subjected to topical anesthetic gel, and group IV underwent TENS (transcutaneous electric nerve stimulation). And then they were asked to measure pain using a visual analog scale (VAS) at 5 intervals of time, i.e., immediately after separator placement, after day 1, day 2, day 3, and day 4. RESULTS: Turkey's post hoc test showed that pain score after immediate placement of separators was found to be the least in the anesthetic gel than that in other groups and pain score was least in the LASER group out of all four groups on day 1, 2, 3, and 4. CONCLUSION: It was found that low-level LASER therapy was more effective in reducing pain after placement of elastomeric separators. HOW TO CITE THIS ARTICLE: Oza MJ, Desai H, Iyengar SS, et al. Comparative Study of Effects of LASER, TENS, and Anesthetic Gel for Controlling Pain after Placement of Elastomeric Separators: A Clinical Trial. Int J Clin Pediatr Dent 2020;13(S-1):S82-S86.

2.
J Clin Exp Dent ; 11(9): e776-e782, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31636868

RESUMEN

BACKGROUND: To comparatively evaluate the esthetic improvement of white-spot lesions (WSLs) treated by: BiominF, CPP-ACP paste with fluoride & ICON resin infiltration, using Spectrophotometer & Diagnodent. MATERIAL AND METHODS: The study was done using 72 sound permanent extracted premolars, divided into four groups (18 teeth per group). After taking the ethical approval the study was commenced. WSLs were created on human premolars and randomly assigned to four groups: Group A: Artificial Saliva, Group B: CPP-ACP with fluoride, Group C: BiominF, Group D: Resin infiltration (Icon). The color change (∆E) of each specimen was measured with a Spectrophotometer (VITA Easy Shade Compact), and fluorescence loss (∆Q) was measured by a laser fluorescence device (DIAGNOdent, Kavo, Biberach, Germany), at different time points after treatment: baseline (0 weeks), 2 weeks, 4 weeks, and 6 weeks. RESULTS: The ∆E and ∆Q baseline values for the four groups before the treatments did not differ significantly. Icon treatment improved the WSL color significantly and gave the lowest ∆E (5.12± 3.92) & ∆Q (1.64 ±0.72) compared with other treatments at end of 6 weeks (P< .01). In the BiominF and CPP-ACP with fluoride treatment groups, ∆Q & ∆E showed significant recovery compared with the baseline values (P< .05). CONCLUSIONS: Within the limitations of the study, it can be concluded that all the three remineralizing agents used in the study could effectively remineralize artificial enamel caries and showed improvement in color change and fluoresence as compared to the baseline. Therefore they can be effectively used for the treatment of the white spot lesions. Key words:White spot lesions(WSL), Resin infiltration (ICON), BiominF, CPP-ACP with fluoride.

3.
Indian J Dent Res ; 29(4): 529-533, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30127208

RESUMEN

BACKGROUND: Developmental anomalies in the number of teeth can result from disturbances in the developing dental lamina of the tooth. The dental lamina may become hyperactive leading to the formation of a supernumerary tooth or may fail to proliferate leading to the congenital absence of a primary or permanent tooth. AIMS: The aim of the study was to assess the prevalence and distribution of hypodontia and hyperdontia in permanent dentition, excluding the third molars in children in Vadodara, Gujarat. SETTING AND DESIGN: A descriptive, analytical, and cross-sectional study was conducted to determine the above-mentioned aims. MATERIALS AND METHODS: In the study, panoramic radiographs of 1816 children (967 girls and 849 boys), aged 8 to 14 years were recorded and inspected for anomalies in the number of teeth. STATISTICAL ANALYSIS USED: The data was analyzed using SPSS version 10.00 (Statistical Package for the Social Sciences, Chicago, USA). Descriptive statistics and Chi-square-test were used to compare the results. The level of significance was set at 0.05. RESULTS: The prevalence of hypodontia was 11.01%, and the most frequently absent tooth was the maxillary lateral incisor. There was an increased prevalence of hypodontia in females and in the mandibular arch of the permanent dentition. The prevalence of hyperdontia was 2.97% and the most common supernumerary tooth was mesiodens. There was an increased prevalence of hyperdontia in males and in the maxillary arch of the permanent dentition. CONCLUSIONS: There was a high prevalence of hypodontia and a low incidence of hyperdontia in the studied population. Prompt diagnosis of these anomalies can help plan treatment modalities at an early age to establish a functional and esthetic dentition.


Asunto(s)
Anodoncia/diagnóstico por imagen , Anodoncia/epidemiología , Dentición Permanente , Radiografía Panorámica , Diente Supernumerario/diagnóstico por imagen , Diente Supernumerario/epidemiología , Adolescente , Niño , Femenino , Humanos , India/epidemiología , Masculino , Prevalencia
4.
Blood ; 126(19): 2230-8, 2015 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-26396093

RESUMEN

The CD32a immunoglobulin G (IgG) receptor (Fcγ receptor IIa) is a potential therapeutic target for diseases in which IgG immune complexes (ICs) mediate inflammation, such as heparin-induced thrombocytopenia, rheumatoid arthritis, and systemic lupus erythematosus. Monoclonal antibodies (mAbs) are a promising strategy for treating such diseases. However, IV.3, perhaps the best characterized CD32a-blocking mAb, was recently shown to induce anaphylaxis in immunocompromised "3KO" mice. This anaphylactic reaction required a human CD32a transgene because mice lack an equivalent of this gene. The finding that IV.3 induces anaphylaxis in CD32a-transgenic mice was surprising because IV.3 had long been thought to lack the intrinsic capacity to trigger cellular activation via CD32a. Such an anaphylactic reaction would also limit potential therapeutic applications of IV.3. In the present study, we examine the molecular mechanisms by which IV.3 induces anaphylaxis. We now report that IV.3 induces anaphylaxis in immunocompetent CD32a-transgenic "FCGR2A" mice, along with the novel finding that IV.3 and 2 other well-characterized CD32a-blocking mAbs, AT-10 and MDE-8, also induce severe thrombocytopenia in FCGR2A mice. Using recombinant variants of these same mAbs, we show that IgG "Fc" effector function is necessary for the induction of anaphylaxis and thrombocytopenia in FCGR2A mice. Variants of these mAbs lacking the capacity to activate mouse IgG receptors not only failed to induce anaphylaxis or thrombocytopenia, but also very potently protected FCGR2A mice from near lethal doses of IgG ICs. Our findings show that effector-deficient IV.3, AT-10, and MDE-8 are promising candidates for developing therapeutic mAbs to treat CD32a-mediated diseases.


Asunto(s)
Anafilaxia/inducido químicamente , Anticuerpos Monoclonales de Origen Murino/efectos adversos , Anticuerpos Neutralizantes/efectos adversos , Receptores de IgG/antagonistas & inhibidores , Trombocitopenia/inducido químicamente , Anafilaxia/inmunología , Anafilaxia/patología , Animales , Anticuerpos Monoclonales de Origen Murino/inmunología , Anticuerpos Monoclonales de Origen Murino/farmacología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/farmacología , Humanos , Ratones , Ratones Transgénicos , Receptores de IgG/genética , Receptores de IgG/inmunología , Trombocitopenia/genética , Trombocitopenia/inmunología , Trombocitopenia/patología
5.
Blood Coagul Fibrinolysis ; 24(5): 510-7, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23406663

RESUMEN

Preoperative evaluation of patients presenting with ovarian masses is challenging, partly due to shortcomings with the commonly used marker, CA-125. Ovarian cancer is associated with systemic coagulation activation. Measurement of D-dimer, serum tissue factor (TF), and the coagulation process as a whole are considered candidates for improving discrimination between benign and malignant ovarian masses. We therefore sought to identify possible benefits by analyzing preoperative coagulation status in conjunction with CA-125 in patients with ovarian masses. Preoperative blood from 95 patients with ovarian masses (75 benign, 20 malignant) and 30 controls was analyzed, prospectively. Thromboelastography served for global hemostatic assessment. Plasma TF antigen and D-dimer were measured by ELISA and microparticle-associated TF activity by thrombin generation assay. TF microparticles were enumerated by flow cytometry. Time to clot formation by thromboelastography was similar between patients having either benign or malignant ovarian tumors. Clot formation rate, clot strength, and coagulation index were significantly increased in patients having malignant versus benign tumors, indicating that thromboelastography differentiated malignant from benign tumors. D-dimer alone differentiated malignant from benign ovarian tumors and also improved differentiation when combined with CA-125. Circulating TF antigen, activity, and TF microparticle numbers, however, failed to differentiate benign from malignant tumors. Significant coagulation activation occurs in women with ovarian malignancies. Plasma D-dimer may help discriminate between patients with benign and malignant tumors. Thromboelastography may also contribute meaningfully when combined with CA-125 in the preoperative evaluation of ovarian masses. Larger studies are needed to assess these possibilities.


Asunto(s)
Coagulación Sanguínea/fisiología , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/fisiopatología , Adulto , Anciano , Biomarcadores de Tumor/sangre , Antígeno Ca-125/sangre , Diagnóstico Diferencial , Femenino , Productos de Degradación de Fibrina-Fibrinógeno , Fibrinógeno/análisis , Hemostasis , Humanos , Persona de Mediana Edad , Periodo Preoperatorio , Sensibilidad y Especificidad , Tromboelastografía , Tromboplastina/análisis
7.
Platelets ; 21(7): 571-4, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20849210

RESUMEN

The multifunctional cytokine, TWEAK (TNF-like weak inducer of apoptosis), is a member of the TNFα superfamily. TWEAK is found in a broad range of cell types and has been linked to cell growth and survival, angiogenesis and other inflammatory processes. These functions and their importance in inflammatory diseases have made TWEAK an attractive pharmaceutical target, particularly for immunotherapy with monoclonal antibodies (mAbs). Immunotherapy targeting another TNFα family member, CD154, was associated with thrombosis in clinical trials. Subsequent studies identified platelets, which contain CD154, as a possible contributing factor to thrombosis in these trials. Since clinical trials with anti-TWEAK mAbs have already begun, we considered it important to determine whether platelets contain TWEAK. Using a variety of immunologic methods we found that, upon activation, human platelets expose TWEAK antigen and release it in soluble form (sTWEAK). By flow cytometry we determined that human platelets activated by TRAP (Thrombin Receptor Agonist Peptide) and other agonists expose TWEAK antigen (22% median positivity) and release TWEAK positive microparticles. The presence of TWEAK on platelets was confirmed by confocal microscopy. By ELISA, we found that sTWEAK is released by activated platelets. Finally, western blot analysis revealed TWEAK protein (34 kDa) in washed platelet lysates. The finding that human platelets contain TWEAK raises important questions about its possible functions in normal physiology, as well as in inflammatory diseases and their treatment.


Asunto(s)
Plaquetas/metabolismo , Receptores del Factor de Necrosis Tumoral/sangre , Citometría de Flujo , Humanos , Receptor de TWEAK
8.
J Immunol ; 185(3): 1577-83, 2010 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-20585032

RESUMEN

Anti-CD40L immunotherapy in systemic lupus erythematosus patients was associated with thromboembolism of unknown cause. We previously showed that monoclonal anti-CD40L immune complexes (ICs) activated platelets in vitro via the IgG receptor (FcgammaRIIa). In this study, we examined the prothrombotic effects of anti-CD40L ICs in vivo. Because mouse platelets lack FcgammaRIIa, we used FCGR2A transgenic mice. FCGR2A mice were injected i.v. with preformed ICs consisting of either anti-human CD40L mAb (M90) plus human CD40L, or a chimerized anti-mouse CD40L mAb (hMR1) plus mouse CD40L. ICs containing an aglycosylated form of hMR1, which does not bind FcgammaRIIa, were also injected. M90 IC caused shock and thrombocytopenia in FCGR2A but not in wild-type mice. Animals injected with hMR1 IC also experienced these effects, whereas those injected with aglycosylated-hMR1 IC did not, demonstrating that anti-CD40L IC-induced platelet activation in vivo is FcgammaRIIa-dependent. Sequential injections of individual IC components caused similar effects, suggesting that ICs were able to assemble in circulation. Analysis of IC-injected mice revealed pulmonary thrombi consisting of platelet aggregates and fibrin. Mice pretreated with a thrombin inhibitor became moderately thrombocytopenic in response to anti-CD40L ICs and had pulmonary platelet-thrombi devoid of fibrin. In conclusion, we have shown for the first time that anti-CD40L IC-induced thrombosis can be replicated in mice transgenic for FcgammaRIIa. This molecular mechanism may be important for understanding thrombosis associated with CD40L immunotherapy. The FCGR2A mouse model may also be useful for assessing the hemostatic safety of other therapeutic Abs.


Asunto(s)
Complejo Antígeno-Anticuerpo/fisiología , Autoanticuerpos/toxicidad , Ligando de CD40/inmunología , Activación Plaquetaria/inmunología , Receptores de IgG/genética , Trombosis/inmunología , Animales , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/biosíntesis , Anticuerpos Monoclonales/toxicidad , Complejo Antígeno-Anticuerpo/administración & dosificación , Complejo Antígeno-Anticuerpo/toxicidad , Autoanticuerpos/administración & dosificación , Autoanticuerpos/uso terapéutico , Humanos , Hibridomas , Ratones , Ratones Noqueados , Ratones Transgénicos , Activación Plaquetaria/genética , Receptores de IgG/deficiencia , Receptores de IgG/fisiología , Proteínas Recombinantes de Fusión/administración & dosificación , Proteínas Recombinantes de Fusión/fisiología , Proteínas Recombinantes de Fusión/toxicidad , Trombosis/sangre
9.
Clin Exp Metastasis ; 26(7): 829-37, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19642003

RESUMEN

It is established that experimental metastasis requires platelet activity. CD154 expressed on and released from activated platelets induces an inflammatory response in endothelial cells and monocytes, including tissue factor production. CD154 has also been shown to activate platelets in vitro and promote thrombus stability in vivo. These CD154 effects may be mediated, at least in part, by CD40 signaling on platelets and vascular endothelial cells. We have previously demonstrated prolonged bleeding and PFA-100 closure times in mice deficient for Cd154 or its receptor Cd40. In the present study, we hypothesized that Cd40 and Cd154 promote lung tumor formation in experimental metastasis in mice. We created mice doubly deficient in Cd40 and Cd154 (Dbl KO) and found them to be both fertile and viable. Injected tumor cells seeded poorly in mice deficient in Cd40 or Cd154, as well as Dbl KO, compared to wild-type mice. We sought to determine whether blood-borne Cd40 versus endothelial Cd40 contribute differentially to reduced experimental lung metastasis, as observed in Cd40 deficient mice. By bone marrow transplantation, we created mice deficient for Cd40 either in the blood compartment but not in the endothelium, or vice versa. We found that mice deficient in blood compartment Cd40 had fewer lung nodules compared to wild-type mice and mice deficient in endothelial Cd40. Our findings suggest an important contribution of the Cd40-Cd154 pathway to experimental lung metastasis. Furthermore, the data points to a selective role for peripheral blood cell Cd40 in this process.


Asunto(s)
Antígenos CD40/inmunología , Ligando de CD40/inmunología , Neoplasias Pulmonares/secundario , Melanoma Experimental/patología , Animales , Trasplante de Médula Ósea , Línea Celular Tumoral , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/patología , Melanoma Experimental/inmunología , Ratones , Ratones Noqueados , Metástasis de la Neoplasia
10.
Thromb Haemost ; 93(6): 1137-46, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15968400

RESUMEN

Our initial finding that CD40- and CD40 ligand (CD40L)-deficient mice displayed prolonged tail bleeding and platelet function analyzer (PFA-100) closure times prompted us to further investigate the role of the CD40-CD40L dyad in primary hemostasis and platelet function. Recombinant human soluble CD40L (rhsCD40L), chemical cross-linking of which suggested a trimeric structure of the protein in solution, activated platelets in a CD40-dependent manner as evidenced by increased CD62P expression. CD40 monoclonal antibody (mAb) M3, which completely blocked rhsCD40L-induced platelet activation, also prolonged PFA-100 closure times of normal human blood. In contrast, CD40 mAb G28-5 showed less potential in blocking rhsCD40L-induced CD62P expression and did not affect PFA-100 closure times. However, when added to the platelets after rhsCD40L, G28-5 significantly enhanced the platelet response by causing clustering of, and signaling through, FcgammaRII. Similarly, higher order multimeric immune complexes formed at a 1/3 molar ratio of M90, a CD40L mAb, to rhsCD40L induced strong Fcgamma RII-mediated platelet activation when translocated to the platelet surface in a CD40-dependent manner, including the induction of morphological shape changes, fibrinogen binding, platelet aggregation, dense granule release, microparticle generation and monocyte-platelet-conjugate formation. The results suggest that CD40 may play a role in primary hemostasis and platelet biology by two independent mechanisms: First, by functioning as a primary signaling receptor for CD40L and, second, by serving as a docking molecule for CD40L immune complexes. The latter would also provide a potential mechanistic explanation for the unexpected high incidence of CD40L mAb-associated thrombotic events in recent human and animal studies.


Asunto(s)
Antígenos CD40/sangre , Ligando de CD40/sangre , Activación Plaquetaria/inmunología , Animales , Anticuerpos Monoclonales/farmacología , Complejo Antígeno-Anticuerpo/sangre , Antígenos CD40/inmunología , Ligando de CD40/farmacología , Hemostasis , Humanos , Técnicas In Vitro , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Activación Plaquetaria/efectos de los fármacos , Receptores de IgG/metabolismo , Proteínas Recombinantes/farmacología
11.
Thromb Haemost ; 90(3): 549-54, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12958625

RESUMEN

Platelets are known to play a role in blood borne metastasis. Previous experimental studies have suggested that platelet GpIIb/IIIa may be a therapeutic target. However, the need for intravenous administration limits the potential application of current GpIIb/IIIa inhibitors to cancer therapy. The aim of the present study was to assess the efficacy of a novel, non-peptide oral GpIIb/IIIa antagonist (XV454) on tumor cell-induced platelet aggregation in vivo and on experimental metastasis. A Lewis lung carcinoma (LL2) mouse model of experimental metastasis was used in this study. XV454 (100 micro g) was administered intravenously (via tail vein) or orally (gavages) to 20 g mice. To determine the effect of XV454 on platelet aggregation, blood samples were collected by cardiac puncture 10 minutes after intravenous and 1-24 hrs after oral XV454, and platelet function was assessed by aggregometry, thrombelastography and the Platelet Function Analyzer (PFA100). The effect of XV454 on tumor cell-induced thrombocytopenia was determined 10 minutes after intravenous and 3 hrs after oral XV454 administration. Tumor cells (2 x 10(6)) were injected intravenously and 15 minutes after cell injection, platelet count was measured and compared to baseline (pre-injection) counts. To assess the effect on metastasis, XV454 was administered intravenous or orally 10 minutes and 3 hrs before tumor cell injection, respectively. Eighteen days later, surface lung tumor nodules were counted and the total lung tumor burden assessed. In a fourth group, in addition to the initial oral dose (before tumor cell injection), oral XV454 was given daily for the first week and three times in the second week. Administration of XV454 (5 mg/kg) completely inhibited platelet aggregation and this effect persisted for at least 24 hrs after oral delivery. Both intravenous and oral XV454 significantly inhibited tumor cell-induced thrombocytopenia (P < 0.01), the number of surface lung tumor nodules (80-85%; P < 0.001) and total tumor burden (83% for intravenous group; 50% oral [single treatment] group; 91% oral [multiple treatment] group, P < 0.001). Overall, these data provide further evidence for the effect of oral and intravenous GpIIb/IIIa antagonism on tumor cell-platelet interaction and metastasis.


Asunto(s)
Alanina/análogos & derivados , Alanina/farmacología , Carcinoma Pulmonar de Lewis/sangre , Neoplasias Pulmonares/tratamiento farmacológico , Metástasis de la Neoplasia/prevención & control , Oxazoles/farmacología , Agregación Plaquetaria/efectos de los fármacos , Administración Oral , Alanina/administración & dosificación , Animales , Carcinoma Pulmonar de Lewis/tratamiento farmacológico , Carcinoma Pulmonar de Lewis/patología , Línea Celular Tumoral , Evaluación Preclínica de Medicamentos , Femenino , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/secundario , Ratones , Ratones Desnudos , Metástasis de la Neoplasia/tratamiento farmacológico , Oxazoles/administración & dosificación , Inhibidores de Agregación Plaquetaria/administración & dosificación , Inhibidores de Agregación Plaquetaria/farmacología , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/antagonistas & inhibidores , Trombocitopenia/etiología , Trombocitopenia/prevención & control
12.
Indian J Med Res ; 117: 260-9, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-14748472

RESUMEN

BACKGROUND & OBJECTIVES: Data on the physical dimension of the hand of Indian women are scanty. This information is necessary to ascertain human-machine compatibility in the design of manual systems for the bare and gloved hand, such as design and sizing of hand tools, controls, knobs and other applications in different kinds of precision and power grips. The present study was undertaken to generate hand anthropometric data of 95 women, working in informal industries (beedi, agarbatti and garment making). METHODS: Fifty one hand measurements of the right hand (lengths, breadths, circumferences, depths, spreads and clearances of hand and fingers) were taken, using anthropometric sliding and spreading calipers, measuring tape and handgrip strength dynamometer. The data were statistically analyzed to determine the normality of data and the percentile values of different hand dimensions, and simple and multiple regression analysis were done to determine better predictors of hand length and grip strength. RESULTS: The hand breadths, circumferences and depths were approximately normally distributed, with some deviation in case of the finger lengths. Hand length was significantly correlated with the fist, wrist and finger circumferences. The fist and wrist circumferences, in combination, were better predictors of hand length. The hand lengths, breadths and depths, including finger joints of the Indian women studied were smaller than those of American, British and West Indian women. The hand circumferences of the Indian women were also smaller than the American women. Grip strengths of Indian women (20.36 +/- 3.24 kg) were less than those of American, British and West Indian women. Grip strength was found to be statistically significant with hand dimensions, such as hand height perpendicular to wrist crease (digit 5), proximal interphalangeal joint breadth (digit 3) and hand spread across wedge 1. INTERPRETATION & CONCLUSION: The women who are forced to frequently use cutters, strippers and other tools, which are not optimally designed to their hand dimensions and strength range, might have higher prevalence of clinical symptoms and disorders of the hand. In view of the human hand-tool interface requirements, the present data on Indian women would be useful for ergo-design applications of hand tools and devices.


Asunto(s)
Mano/anatomía & histología , Adolescente , Adulto , Antropometría , Ergonomía , Femenino , Humanos , India , Persona de Mediana Edad , Salud Laboral
13.
Hematol J ; 3(5): 264-70, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12391545

RESUMEN

Vascular endothelial growth factor (VEGF) is an angiogenic hormone that increases the growth of many malignant tumors. Tissue factor (TF), the initiator of blood coagulation, is implicated in VEGF regulation. We recently reported that hemoglobin (Hb) upregulates TF on malignant cells. Therefore, to explore the role of Hb in angiogenesis, we examined its effect on VEGF production in A375 melanoma and J82 bladder carcinoma (TF+) and KG1 myeloid leukemia (TF-) cells. Hb (0.50 mg/ml) induced VEGF expression and secretion in TF+ malignant cells. VEGF secretion was inhibited by cycloheximide (85%) and the specific inhibitors of protein tyrosine kinase, genistein (71+/-0.74 and 55+/-4.90%) and mitogen-activated protein (MAP)-kinase, PD098059 (82+/-2.0 and 59+/-6.7%) in A375 and J82 cells respectively. In contrast, Hb (2.0 mg/ml) did not increase VEGF in KG1 cells. Hb-induced VEGF was purified from the culture medium of J82 cells using immunoaffinity chromatography and two isoforms (46 and 30 kd) identified. We conclude that Hb-induced synthesis of VEGF in TF-bearing malignant cells is mediated by protein tyrosine kinase and by MAP-kinase pathways.


Asunto(s)
Factores de Crecimiento Endotelial/biosíntesis , Regulación de la Expresión Génica/efectos de los fármacos , Hemoglobinas/farmacología , Péptidos y Proteínas de Señalización Intercelular/biosíntesis , Linfocinas/biosíntesis , Neoplasias/patología , Factores de Crecimiento Endotelial/metabolismo , Inhibidores Enzimáticos/farmacología , Hemoglobinas/fisiología , Humanos , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Linfocinas/metabolismo , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas Activadas por Mitógenos/fisiología , Neoplasias/metabolismo , Isoformas de Proteínas/aislamiento & purificación , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Proteínas Tirosina Quinasas/fisiología , Transducción de Señal , Tromboplastina , Células Tumorales Cultivadas , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
14.
Platelets ; 13(4): 247-53, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12189027

RESUMEN

Tissue factor (TF) is a transmembrane receptor for FVII that triggers blood coagulation. It is not normally exposed to circulating blood, but may be produced by endothelium and monocytes under pathological conditions. Platelets take up TF-positive microparticles from leukocytes and TF appears on platelets adhering to leukocytes following collagen stimulation of blood. However, the presence of TF in circulating platelets has not been directly demonstrated. In this study, flow cytometric analysis of washed platelets from five healthy adult volunteers demonstrated TF-antigen on both resting platelets and platelets activated by thrombin (0.1 U/ml), collagen (5 microg/ml) or ADP (5 microM). TF released by platelets was demonstrated in the supernatants of non-activated and activated washed platelets by dot-immunoblotting and Western blotting. The amount of TF released from non-activated and activated platelets was quantitated using an enzyme-linked immunosorbent assay (ELISA). Washed non-activated and platelets activated by thrombin, collagen or ADP released 27-35 pg TF per mg protein. TF associated with the platelet surface was biologically inactive, although released TF was functionally active as determined by a two-stage factor X activation assay. We conclude that platelets contain an inactive form of TF that may develop functional activity following its release. However, the role of platelet TF in health and disease remains to be determined.


Asunto(s)
Plaquetas/metabolismo , Tromboplastina/metabolismo , Adenosina Difosfato/farmacología , Pruebas de Coagulación Sanguínea , Plaquetas/química , Colágeno/farmacología , Ensayo de Inmunoadsorción Enzimática , Factor X/metabolismo , Citometría de Flujo , Humanos , Activación Plaquetaria/efectos de los fármacos , Activación Plaquetaria/fisiología , Trombina/farmacología , Tromboplastina/fisiología
15.
Thromb Haemost ; 87(6): 930-6, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12083498

RESUMEN

The importance of tissue factor (TF) in tumor biology has been highlighted by studies suggesting its involvement in cell signaling, metastasis and angiogenesis. Since many animal studies have shown that anticoagulant therapy can reduce experimental metastasis, we studied whether the natural inhibitor of TF-mediated blood coagulation, Tissue Factor Pathway Inhibitor (TFPI), might be similarly effective. Using a murine experimental model, we found that intravenous injection of recombinant murine TFPI immediately before introduction of tumor cells reduced metastasis by 83% (P < 0.001). B16 murine melanoma cells stably transfected with a TFPI expression vector exhibited reduced lung seeding following intravenous injection by 81% (P < 0.001) compared with controls. No difference in primary tumor growth was observed between TFPI+ and control cells. Mice receiving intravenous somatic gene transfer of sense TFPI expression vector developed 78% fewer lung nodules than controls (P < 0.05). We conclude that TFPI has significant anti-metastatic activity in this experimental model.


Asunto(s)
Anticoagulantes/farmacología , Lipoproteínas/farmacología , Neoplasias Pulmonares/secundario , Melanoma Experimental/patología , Metástasis de la Neoplasia/prevención & control , Animales , Anticoagulantes/administración & dosificación , Factores de Crecimiento Endotelial/metabolismo , Femenino , Heparina/administración & dosificación , Heparina/farmacología , Inyecciones Intravenosas , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Lipoproteínas/administración & dosificación , Neoplasias Pulmonares/tratamiento farmacológico , Linfocinas/efectos de los fármacos , Linfocinas/metabolismo , Melanoma Experimental/complicaciones , Melanoma Experimental/tratamiento farmacológico , Ratones , Ratones Endogámicos C57BL , Metástasis de la Neoplasia/tratamiento farmacológico , Recuento de Plaquetas , Trombocitopenia/tratamiento farmacológico , Trombocitopenia/etiología , Trombocitopenia/prevención & control , Trombofilia/tratamiento farmacológico , Trombofilia/etiología , Trombofilia/prevención & control , Transfección , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
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