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1.
Biochem Biophys Res Commun ; 516(2): 408-413, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31221477

RESUMO

Aberrant activity of the hedgehog (Hh) pathway is prevalent in pathologies such as cancer. Improved understanding of Hh activity in the aggressive tumor cell phenotype is being pursued for development of targeted therapies. Recently, we described a link between Hh activity and carbonic anhydrase XII (CAXII) expression. Extracellular facing CAs (IX/XII) are highly expressed in hypoxia, contribute to tumor pH regulation and are thus of clinical interest. Here we have extended the investigation of potential interactions between Hh activity and CAXII utilizing genomic disruption/knockout of either GLI1 (the main transcriptional factor induced with Hh activity) or CAXII in the triple negative breast cancer cell lines MDA-MB-231 and BT-549. Knockout of GLI1 and CAXII significantly decreased hallmarks of tumor aggressiveness including proliferation and migration. Most intriguingly, CAXII knockout caused a massive induction of the Sonic hedgehog (Shh) ligand expression (gene and protein). This novel finding indicates that CAXII plays a potential role in suppression of Shh and may act in a feedback loop to regulate overall Hh activity. Enhanced knowledge of these CA-Hh interactions in future studies may be of value in understanding this currently 'incurable' subclass of breast cancer.


Assuntos
Anidrases Carbônicas/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Proteína GLI1 em Dedos de Zinco/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Técnicas de Inativação de Genes , Genoma , Heterozigoto , Humanos , Invasividade Neoplásica
2.
Nature ; 504(7478): 122-5, 2013 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-24196707

RESUMO

Olivine is a major component of the mantle of differentiated bodies, including Earth. Howardite, eucrite and diogenite (HED) meteorites represent regolith, basaltic-crust, lower-crust and possibly ultramafic-mantle samples of asteroid Vesta, which is the lone surviving, large, differentiated, basaltic rocky protoplanet in the Solar System. Only a few of these meteorites, the orthopyroxene-rich diogenites, contain olivine, typically with a concentration of less than 25 per cent by volume. Olivine was tentatively identified on Vesta, on the basis of spectral and colour data, but other observations did not confirm its presence. Here we report that olivine is indeed present locally on Vesta's surface but that, unexpectedly, it has not been found within the deep, south-pole basins, which are thought to be excavated mantle rocks. Instead, it occurs as near-surface materials in the northern hemisphere. Unlike the meteorites, the olivine-rich (more than 50 per cent by volume) material is not associated with diogenite but seems to be mixed with howardite, the most common surface material. Olivine is exposed in crater walls and in ejecta scattered diffusely over a broad area. The size of the olivine exposures and the absence of associated diogenite favour a mantle source, but the exposures are located far from the deep impact basins. The amount and distribution of observed olivine-rich material suggest a complex evolutionary history for Vesta.

3.
Ann Hematol ; 92(10): 1405-12, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23771477

RESUMO

In the last 30 years, the use of long-term central venous catheters (CVC) is increased especially for children with hemato-oncological disorders. However, the use of CVC is associated to complications, as mechanical accidents, thrombosis, and infections that can determine a prolongation of hospital stay, an increase of costs, and sometimes life-threatening conditions that require urgent systemic treatment or CVC removal. CVC removal may be troublesome especially in neonates, infants, or any other "highly needed CVC patients"; in these selected cases, the prevention and treatment of CVC-related complications play a pivotal role and specific surveillance programs are crucial. While extensive literature is focused on CVC management in adults, no guidelines are available for children. To this aim, the first recommendations for the management of CVC infectious complication in pediatric age have been written after pediatric and adult literature review and collegial discussion among members of Supportive Therapy working group of Italian Association of Pediatric Hematology and Oncology. Compared to the adult age, the necessity of peripheral vein cultures for the diagnosis of CVC-related infection remains controversial in children because of the poorer venous asset and a conservative, pharmacologically focused management through CVC remains mandatory, with CVC removal to be performed only in selected cases.


Assuntos
Infecções Relacionadas a Cateter/prevenção & controle , Cateterismo Venoso Central/efeitos adversos , Cateteres de Demora/efeitos adversos , Humanos , Trombose/prevenção & controle
4.
Bone Marrow Transplant ; 56(3): 586-595, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32968215

RESUMO

T-cell replete hematopoietic stem cell transplantation (HSCT) from a haploidentical donor followed by high doses of cyclophosphamide has been demonstrated to provide the best chances of a cure for many children in need of an allograft but who lack both a sibling and an unrelated donor. In this study we retrospectively compared the outcome of pediatric patients undergoing T-replete haploidentical HSCT (Haplo) for acute leukemia with those undergoing transplantation from unrelated HLA-matched donor (MUD) and HLA mismatched unrelated donor (MMUD) from 2012 to 2017 at our Center. Both univariable and multivariable analyses showed similar 5-year overall survival rates for MUD, MMUD, and Haplo patients: 71% (95% CI 56-86), 72% (95% CI 55-90), and 75% (95% CI 54-94), respectively (p = 0.97). Haplo patients showed reduced event-free survival rates compared to MUD and MMUD patients: 30% (95% CI 12-49) versus 70% (95% CI 55-84) versus 53% (95% CI 35-73), respectively (p = 0.007), but these data were not confirmed by a multivariable analysis. Non-relapse mortality (NRM) and relapse incidence (RI) were similar for the three groups. Therefore, our data confirm that Haplo is a suitable clinical option for pediatric patients needing HSCT when lacking both an MUD and an MMUD donor.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Criança , Ciclofosfamida , Humanos , Estudos Retrospectivos , Doadores não Relacionados
5.
Chem Sci ; 11(13): 3397-3404, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-34777742

RESUMO

Biocomposites composed of Zeolitic Imidazolate Frameworks (ZIFs) are generating significant interest due to their facile synthesis, and capacity to protect proteins from harsh environments. Here we systematically varied the composition (i.e. relative amounts of ligand (2-methylimidazole), metal precursor (Zn(OAc)2·2H2O), and protein) and post synthetic treatments (i.e. washes with water or water/ethanol) to prepare a series of protein@ZIF biocomposites. These data were used to construct two ternary phase diagrams that showed the synthesis conditions employed gave rise to five different phases including, for the first time, biocomposites based on ZIF-CO3-1. We examined the influence of the different phases on two properties relevant to drug delivery applications: encapsulation efficiency and release profile. The encapsulation efficiencies of bovine serum albumin and insulin were phase dependent and ranged from 75% to 100%. In addition, release profiles showed that 100% protein release varied between 40 and 300 minutes depending on the phase. This study provides a detailed compositional map for the targeted preparation of ZIF-based biocomposites of specific phases and a tool for the straightforward analysis of the crystalline phases of ZIF based materials (web application named "ZIF phase analysis"). These data will facilitate the progress of ZIF bio-composites in the fields of biomedicine and biotechnology.

6.
Cell Immunol ; 249(2): 63-72, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18163982

RESUMO

Bisphosphonates have a profound effect on bone resorption and are widely used in the treatment of osteoclast-mediated bone diseases. Zoledronic acid (ZA), a third-generation biphosphonate, has a potent antitumor activity and expands gammadelta (gammadelta) T cells endowed of major histocompatibility complex-unrestricted lytic activity. Many solid tumors express tumor-specific antigens on their surface, representing targets for immune effector T cells. Nevertheless, the immune surveillance against clinically manifested tumors is relatively inefficient. Therefore, we investigated the hitherto unknown effects of ZA activated gammadelta T cells of normal donors on osteosarcoma cell lines. gammadelta T cells were stimulated with ZA and low doses of interleukin-2, and then analyzed for proliferation and generation of effector activity against osteosarcoma cell lines. Our results show the potent anti-tumor activity of ZA-stimulated gammadelta T cells and the enhanced immunosensitivity of osteosarcoma cell lines to gammadelta T cells suggesting that osteosarcoma is another gammadelta T cell susceptible tumor type.


Assuntos
Antineoplásicos/farmacologia , Difosfonatos/farmacologia , Imidazóis/farmacologia , Osteossarcoma/imunologia , Receptores de Antígenos de Linfócitos T gama-delta , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/imunologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Técnicas de Cocultura , Testes Imunológicos de Citotoxicidade , Citometria de Fluxo , Humanos , Imunoterapia/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ácido Zoledrônico
7.
Am J Clin Nutr ; 55(5): 959-62, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1570804

RESUMO

Two groups of normal volunteers were studied for 5 d of dietary control followed by 3 d of fasting. One group (n = 5) was given a control diet of 0.9 g protein.kg-1.d-1 and the other group (n = 7) was given a high-protein (HP) diet (2.5 g protein.kg-1.d-1). Both groups received 175.56 kJ.kg-1.d-1 (42 kcal.kg-1.d-1). The HP diet but not the control diet caused a significant retention of nitrogen. Postabsorptive leucine kinetics as assessed with [1,2-13C]leucine were similar in the two groups. In the control subjects, the rate of nitrogen excretion did not change in response to fasting, but leucine oxidation increased. In contrast, nitrogen excretion progressively decreased with fasting after the HP diet. Leucine rate of appearance was increased after fasting after the HP diet but oxidation was not increased, meaning that the calculated rate of whole-body protein synthesis was higher than in the control group. The response to a short period of food deprivation is dependent on prior protein intake.


Assuntos
Proteínas Alimentares/administração & dosagem , Jejum/fisiologia , Humanos , Leucina/farmacocinética , Masculino , Nitrogênio/metabolismo , Nitrogênio/urina , Oxirredução
8.
J Interferon Cytokine Res ; 15(2): 137-42, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8590317

RESUMO

We studied the effects of pharmacologically attainable concentrations of interferon-alpha (IFN-alpha) and gamma (IFN-gamma) on the growth of cells incubated under hypoxic conditions (2% O2; approximately 14 mm Hg partial pressure) or exposed to oxygen at atmospheric pressure (21% O2; approximately 147 mm Hg). The cells were from four IFN-sensitive lines: A-549 lung carcinoma and G-361 human melanoma cells grow better under hypoxic conditions, but the growth of Hep-2 laryngeal carcinoma and WISH amnion cells is not affected by the environmental oxygen tension. The antiproliferative effects of the IFN were assessed in terms of cell cloning efficiency and also from the number of cells, relative to controls, measured 1, 2, and 3 days after seeding. Under hypoxic conditions, the cloning efficiency of A-549 and G-361 cells was increased, and they became significantly less responsive to the antiproliferative effect of IFN, and especially of IFN-gamma. No such effects were seen with WISH or Hep-2 cells. Hypoxic conditions are found in the necrotic areas present in most solid tumors, and our results suggest that these may decrease the antiproliferative effects of IFN. They may in part explain why IFNs have so little antitumor activity in such tumors, and they also suggest methods that may increase this activity.


Assuntos
Hipóxia Celular , Interferons/farmacologia , Antineoplásicos/farmacologia , Divisão Celular , Linhagem Celular Transformada , Humanos , Interferon alfa-2 , Interferon-alfa/metabolismo , Interferon-alfa/farmacologia , Interferon gama/farmacologia , Interferon gama/fisiologia , Interferons/fisiologia , Proteínas Recombinantes , Células Tumorais Cultivadas
9.
Curr Pharm Des ; 9(7): 511-9, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12570799

RESUMO

Angiogenesis is a complex process, where several cell types and mediators interact to establish a specific microenvironment suitable for the formation of new capillaries from pre-existing vessels. Such biological processes occur in several physiological conditions, such as embryo development and wound healing, as well as in pathological conditions, including tumours and diabetic retinopathy. T lymphocytes, neutrophils and monocytes fully participate in the angiogenic process by secreting cytokines that may control endothelial cell (EC) proliferation, their survival and apoptosis, as well as their migration and activation. Angiogenesis is the result of a net balance between the activities exerted by positive and negative regulators. This balance is conceptually very similar to that of the Th1/Th2 cells that modulate an appropriate and specific immune response. Th1 or Th2 cytokines may control angiogenesis directly, by acting on cell growth and differentiation, indirectly by inducing the release of other cytokines in the microenvironment, and by modulating the expression of specific receptors, involved in the control of angiogenic processes, such as EC proliferation and migration. In this review we will mainly discuss the role of Th1- and Th2-type cytokines in the angiogenic process, emphasizing the complexity of the cytokine and leukocyte/EC network, and highlighting the care that needs to be taken when designing new therapeutic interventions involving Th1 and Th2 cytokines.


Assuntos
Citocinas/fisiologia , Neovascularização Patológica/metabolismo , Neovascularização Fisiológica/fisiologia , Células Th1/fisiologia , Células Th2/fisiologia , Divisão Celular/fisiologia , Citocinas/biossíntese , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiologia , Humanos , Neoplasias/irrigação sanguínea , Neoplasias/metabolismo , Células Th1/metabolismo , Células Th2/metabolismo
10.
Br J Pharmacol ; 140(5): 980-6, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14517182

RESUMO

In addition to its central role in blood coagulation and hemostasis, human alpha-thrombin is a powerful regulator of inflammatory responses and is known to affect cell-mediated immunity. Interleukin (IL)-12 is a strong promoter of the development of Th1-type lymphocytes and its downregulation implies a positive feedback mechanism for development of Th2 responses. We have previously shown that thrombin enhances the release of IL-6, a Th2-related cytokine, in human peripheral blood mononuclear cells (PBMC). Here we show that thrombin downregulates IL-12 production at both protein and mRNA levels in human PBMC. The inhibition of IL-12 production was accompanied by an enhanced release of IL-10, which inhibits Th1-related processes and promotes Th2-type responses. The use of proteolytically inactive thrombin and of the specific thrombin receptor agonist peptide, SFLLRN, reveals that this downregulation is thrombin-specific and requires thrombin proteolytic activity. In addition, activation of coagulation inhibits IL-12 production in whole blood cultures, confirming the tight relationship between the coagulation pathway, where thrombin is a key enzyme, and inflammation. Decreased IL-12 production appears to be related also to IL-10 production, since the addition of an anti-IL-10 monoclonal antibody to thrombin-treated PBMC resulted in a partial restoration of IL-12 production. In conclusion, the observation that thrombin significantly affects the production of IL-12, as well as of IL-10, implies a concerted role orchestrated by thrombin in PBMC that could be crucial to effective immunity and inflammation.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Interleucina-12/antagonistas & inibidores , Interleucina-12/biossíntese , Células Th1/efeitos dos fármacos , Células Th2/efeitos dos fármacos , Trombina/farmacologia , Regulação da Expressão Gênica/imunologia , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Células Th1/imunologia , Células Th1/metabolismo , Células Th2/imunologia , Células Th2/metabolismo
11.
Metabolism ; 40(6): 553-61, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1865818

RESUMO

Fibronectin is an opsonic protein that, among other functions, activates the reticuloendothelial system. Accurate measurement of its rate of synthesis is necessary to more fully understand its physiological role in normal and pathological conditions. We have determined the rate of fibronectin synthesis in three normal volunteers using a primed-constant infusion of 15N-glycine and 1,2-13C-leucine, and measuring the incorporation of the isotopes into the protein over 5 days of infusion. In nine additional subjects, the fractional synthetic rate (FSR) of fibronectin was calculated during a 24-hour infusion using urinary hippurate and plasma alpha-ketoisocaproic acid enrichment to represent the precursors for incorporation of labeled glycine and leucine, respectively, into fibronectin. The FSR using glycine and leucine was 1.56 +/- 0.14 and 1.29 +/- 0.04 (%/h), respectively, in the 5-day infusion study, and 1.56 +/- 0.10 versus 1.83 +/- 0.09 (%/h), respectively, in the 24-hour study. The results of the 5-day infusion of 15N-glycine justify the use of urinary hippurate to reflect the precursor enrichment for the determination of the FSR of fibronectin during a shorter (less than 24 hour) infusion period.


Assuntos
Fibronectinas/biossíntese , Glicina/metabolismo , Leucina/metabolismo , Isótopos de Carbono , Glicina/administração & dosagem , Glicina/sangue , Hipuratos/urina , Humanos , Infusões Intravenosas , Marcação por Isótopo/métodos , Cinética , Leucina/administração & dosagem , Modelos Biológicos , Isótopos de Nitrogênio
12.
J Appl Physiol (1985) ; 75(3): 1180-5, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8226527

RESUMO

A primed constant infusion of [15N2]urea was used to quantify the response of urea production to exercise at 40 and 70% maximal oxygen consumption on a treadmill. Total urea production, urea production from recycled N, urea production from nonrecycled N, and urea N recycled back into body protein were calculated. Most components of urea kinetics were unaffected by exercise at either intensity. The rate of urea reincorporated into protein was significantly increased during exercise and recovery at both levels of exercise. We conclude that exercise does not stimulate urea production but that there may be an accelerated reincorporation of urea N back into body protein.


Assuntos
Esforço Físico , Ureia/metabolismo , Adulto , Humanos , Cinética , Masculino , Consumo de Oxigênio , Ureia/sangue , Ureia/urina
13.
J Appl Physiol (1985) ; 66(2): 591-7, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2708190

RESUMO

The precise mechanism responsible for the increase in plasma lactate concentration during exercise in humans is not known. We have used dichloroacetate to test the hypothesis that a limitation in pyruvate dehydrogenase activity is responsible for the rise in plasma lactate. Dichloroacetate stimulates the activity of pyruvate dehydrogenase, which is normally the regulatory enzyme in the oxidation of glucose when tissue oxygenation is adequate. Six subjects were studied twice according to a randomized, crossover protocol, involving one test with saline infusion and another with dichloroacetate infusion. Exercise load on a bicycle ergometer was increased progressively until exhaustion. Blood samples were drawn each minute throughout exercise and periodically throughout 120 min of recovery. Dichloroacetate significantly lowered the lactate concentration during exercise performed at less than 80% of the average maximal O2 consumption. The peak concentration of lactate at exhaustion was not affected by dichloroacetate treatment, but dichloroacetate did lower lactate concentration throughout recovery. These results suggest that a limitation in pyruvate dehydrogenase activity contributes to the increase in plasma lactate during submaximal exercise and recovery.


Assuntos
Acetatos/farmacologia , Ácido Dicloroacético/farmacologia , Lactatos/sangue , Esforço Físico , Adulto , Humanos , Ácido Láctico , Masculino , Modelos Biológicos , Modelos Teóricos , Consumo de Oxigênio , Complexo Piruvato Desidrogenase/metabolismo
14.
J Cataract Refract Surg ; 20(2): 124-8, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8201559

RESUMO

In a prospective, randomized clinical trial, 42 patients received a monofocal intraocular lens and 38 a multifocal lens after extracapsular cataract extraction. Patients were examined three, six, and 12 months after surgery. Uncorrected visual acuity was 20/40 or better in 57% of monofocal and 58% of multifocal patients; 12% and 52% had near uncorrected visual acuity of J1 to J2, respectively. Best corrected visual acuities were not significantly different. Forty-eight percent of the multifocal and 8% of the monofocal group did not require spectacle correction. On a patient satisfaction questionnaire, 60% of all patients reported discomfort when using spectacles for near vision. Patients in the multifocal group were more satisfied with their near vision than those in the monofocal group. The difference in satisfaction was not significantly different although more multifocal patients reported visual phenomena (e.g., glare, halos). Mean contrast sensitivity for the monofocal group and the multifocal group was 1.73 and 1.70, respectively. At low contrast sensitivities, the difference was not significant although the monofocal patients scored better.


Assuntos
Extração de Catarata/métodos , Cápsula do Cristalino/cirurgia , Lentes Intraoculares , Óptica e Fotônica , Satisfação do Paciente , Acuidade Visual , Idoso , Idoso de 80 Anos ou mais , Sensibilidades de Contraste , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
15.
Med Sci Sports Exerc ; 26(3): 348-53, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8183099

RESUMO

There is little doubt that pyruvate contributes to the increased alanine flux in exercise, but the role of protein breakdown is less clear. To quantify the relative contributions of pyruvate and protein breakdown to the increase in alanine flux observed in exercise, we used a primed, constant infusion of 15N-alanine and 1-13C-lactate. The rate of appearance of alanine, the de novo synthesis of alanine, and rate of alanine release from protein breakdown were determined in five healthy subjects at rest and during exercise. The exercise was performed for 120 min on a treadmill at 45% of the subject's VO2max. The total rate of appearance of alanine, calculated with the 15N-alanine tracer, increased significantly during exercise from 4.9 +/- 0.5 to 7.9 +/- 0.9 mumol.kg-1. The amount of alanine derived from pyruvate also significantly increased during exercise (3.2 +/- 0.3 vs 4.5 +/- 0.7), but the proportion of the total decreased from 65% at rest to 57% during exercise (statistically significant, P < 0.05). Consequently, the alanine derived from protein breakdown significantly increased (1.7 +/- 0.5 vs 3.4 +/- 0.8) and was also increased as percent of total alanine flux. Thus, we conclude that during low-intensity exercise, whole body protein catabolism is accelerated.


Assuntos
Alanina/biossíntese , Exercício Físico/fisiologia , Adulto , Alanina/sangue , Humanos , Lactatos/sangue , Ácido Láctico , Masculino
16.
J Biol Regul Homeost Agents ; 4(4): 153-6, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2096600

RESUMO

It is uncertain whether interferon levels in the interstitial fluid of tumors are equivalent to interferon plasma levels and we have investigated this problem in human pulmonary tumors by infusing human recombinant interferon alpha A and natural interferon Beta for about three hours before surgery. By determining the hematocrit and hemoglobin content it was possible to calculate interferon values (International Units/g wet tissue) present in the interstitial fluid of tumor and lung samples, simultaneously. In 14 patients (epidermoids, n = 9 and adenocarcinomas, n = 5) interferon levels in tumor and "normal" lung expressed as percentages of interferon plasma levels were: 9.5 +/- 3.9 and 29.8 +/- 6.9 for recombinant interferon alpha A and 3.1 +/- 0.4 and 10.1 +/- 2.4 for natural interferon Beta, respectively. Differences for both interferons are statistically significant (p less than 0.05). To our knowledge these are the first data indicating that interferon levels in pulmonary tumor interstitial fluid are markedly lower than those in normal lung although they do not clarify the main factor responsible for the decrease, they explain at least in part the negligible therapeutic activity of interferons in these tumors and emphasize the need for new approaches for improving the therapeutic index of interferons.


Assuntos
Interferon Tipo I/metabolismo , Neoplasias Pulmonares/imunologia , Adulto , Idoso , Espaço Extracelular/imunologia , Feminino , Humanos , Infusões Intravenosas , Interferon Tipo I/administração & dosagem , Interferon Tipo I/sangue , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Interferon-alfa/sangue , Interferon-alfa/metabolismo , Cinética , Neoplasias Pulmonares/sangue , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes
17.
Physiol Res ; 42(4): 243-50, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8280722

RESUMO

We have evaluated whether the addition of either bradykinin or histamine favours the lymphatic absorption of human recombinant interferon-alpha 2 (IFN-alpha 2) administered by the subcutaneous route. Subcutaneous administration of IFN-alpha 2 with bradykinin enhances IFN absorption via both capillaries and lymphatics, so that either the plasma or lymph areas under the concentration curves (AUC) increase significantly up to 1751 +/- 483 and 1319 +/- 608 IU/ml/min respectively as compared to the respective AUC values (613 +/- 208 and 483 +/- 213 IU/ml/min) obtained after IFN injection in normal saline. Since the lymph AUC/plasma AUC ratios remain unaltered, there is no preferential lymphatic absorption of IFN-alpha 2 after bradykinin administration. Dual-label experiments, 125I-IFN-alpha 2 in saline and 131I-IFN-alpha in saline containing 200 micrograms histamine were injected subcutaneously into the left and into the right shank of the same animal, gave similar results. The kinetics of 125I and 131I acid-soluble radioactivity confirm that histamine favours both plasmatic and lymphatic absorption.


Assuntos
Bradicinina/administração & dosagem , Histamina/administração & dosagem , Interferon Tipo I/farmacocinética , Sistema Linfático/metabolismo , Animais , Disponibilidade Biológica , Interações Medicamentosas , Humanos , Injeções Subcutâneas , Interferon Tipo I/administração & dosagem , Masculino , Coelhos , Proteínas Recombinantes , Distribuição Tecidual
18.
Arch Latinoam Nutr ; 51(3): 276-83, 2001 Sep.
Artigo em Português | MEDLINE | ID: mdl-11795242

RESUMO

The objective of this study was to evaluate the effect of the soaking step and the domestic processing of the common bean, on the chemical composition, the levels of phytate, tannin, starch and flatulence factors by utilizing the follows treatments: raw bean (FC), freeze-dried cooked unsoaked bean (FCSM), freeze-dried cooked bean without the non-absorbed soaking water (FCSAM), freeze-dried cooked bean with the non-absorbed soaking water (FCCAM) and the soaking water (AM). The beans were soaking for a period for 16 hours in the proportion 3:1 (water:beans) at room temperature. The effect of the phytates and tannins on the net protein efficiency ratio (NPR) and protein digestibility using male Wistar rats were studied. A decrease in the phytate content of the beans (85%) with use of soaking was observed. In the case of the tannin content, only the cooking of the beans promoted high decomposition (84%). In the (FCSAM) treatment a decrease in the raffinose (25.0%), stachiose (24.8%), verbascose (41.7%) and starch (26.8%) contents was observed. Diets containing casein (control), casein plus the soluble solids obtain from the soaking water showed no significant difference (p > 0.05) for the NPR, as well as for the different bean treatments, although these showing lower values. The treatment (FCSM) showed the higher digestibility (74.3 +/- 5.8%) of the bean treatments, the casein diets showing 94.6 +/- 0.9%. The reduction of the phytates, tannin, starch contents and flatulence factors in the common bean was most effective when the soaking water not absorbed was discarded (FCSAM).


Assuntos
Carboidratos/análise , Flatulência/metabolismo , Manipulação de Alimentos/métodos , Phaseolus/química , Animais , Culinária/métodos , Digestão , Glucosídeos/análise , Masculino , Valor Nutritivo , Oligossacarídeos/análise , Ácido Fítico/análise , Rafinose/análise , Ratos , Ratos Wistar , Amido/análise , Taninos/análise
19.
Science ; 336(6082): 697-700, 2012 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-22582257

RESUMO

The mineralogy of Vesta, based on data obtained by the Dawn spacecraft's visible and infrared spectrometer, is consistent with howardite-eucrite-diogenite meteorites. There are considerable regional and local variations across the asteroid: Spectrally distinct regions include the south-polar Rheasilvia basin, which displays a higher diogenitic component, and equatorial regions, which show a higher eucritic component. The lithologic distribution indicates a deeper diogenitic crust, exposed after excavation by the impact that formed Rheasilvia, and an upper eucritic crust. Evidence for mineralogical stratigraphic layering is observed on crater walls and in ejecta. This is broadly consistent with magma-ocean models, but spectral variability highlights local variations, which suggests that the crust can be a complex assemblage of eucritic basalts and pyroxene cumulates. Overall, Vesta mineralogy indicates a complex magmatic evolution that led to a differentiated crust and mantle.

20.
Curr Med Chem ; 18(19): 2885-92, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21651491

RESUMO

The tumor microenvironment is characterized, not only by marked gradients in drug concentration, but also by gradients in the rate of cell proliferation and by regions of hypoxia and acidity, all of which can influence tumor cell sensitivity to drug treatment. Hypoxia is also an important environmental factor in chronic myeloid leukemia (CML), because bone marrow is intrinsically hypoxic in nature. Systems-wide analyses of tumors have recently identified receptor tyrosine kinase coactivation as an important mechanism by which cancer cells achieve chemoresistance. Recent work suggests that Src activation might play a prominent role in the response to hypoxia to promote cell survival, progression, and metastasis of a variety of human cancer. Other studies also established a functional link between Bcr-Abl and the Src family tyrosine kinases. It is well known that mutations can also cause some tyrosine kinases to become constitutively active, a nonstop functional state that may contribute to initiation or progression of cancer as in CML. Leukemic cells carrying chromosomal alteration, are sensitive to imatinib that induces complete remission in most patients. This inhibitor is a highly selective Bcr-Abl tyrosine kinase inhibitor (TKI). There is a considerable interest in understanding how activated signaling pathways enhance tumor cell survival under hypoxia, because this might lead to the introduction of more effective treatments to target these resistant subpopulations. For all these reasons it is important to identify new TKIs which are also active in hypoxia, the real tumor microenvironment, as possible alternative therapy.


Assuntos
Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Microambiente Tumoral/efeitos dos fármacos , Animais , Antineoplásicos/uso terapêutico , Hipóxia Celular/efeitos dos fármacos , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Proteínas de Fusão bcr-abl/metabolismo , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Quinases da Família src/antagonistas & inibidores , Quinases da Família src/metabolismo
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