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1.
Biomed Pharmacother ; 60(5): 227-32, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16757146

RESUMEN

In this study we observed the effects in vivo of hyperthermic treatment on the cell kinetics (cell proliferation/cell death) in one case of human non-Hodgkin lymphoma, by analyzing the following morpho-cytochemical parameters: Acridine Orange fluorochromasia, mitotic index, proliferating cell nuclear antigen (PCNA) expression, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) labeling, and ultrastructure morphology. After two hyperthermic exposures there was a significant reduction of cell growth rate (e.g. mitotic and PCNA positive cells) and an increase in cell loss by death. The cell death occurred by the typical apoptotic cascade, namely DNA fragmentation, chromatin hypercondensation and margination, karyorrhexis, ribonucleoproteins segregation and cytoplasm cleavage; in addition some necrotic cells were found. The data indicates that the hyperthermic treatments limit the cell proliferation (e.g. arrest and/or deceleration of the cell cycle) by facilitating the trigger of programmed cell death. It was concluded that thermal injury can be considered an effective inducer of antiproliferative and apoptogenic associated effects on the growth of this kind of neoplasia.


Asunto(s)
Hipertermia Inducida , Linfoma no Hodgkin/terapia , Apoptosis/efectos de los fármacos , Recuento de Células , Muerte Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Terapia Combinada , Fragmentación del ADN , ADN de Neoplasias/biosíntesis , ADN de Neoplasias/genética , Humanos , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Cinética , Linfoma no Hodgkin/tratamiento farmacológico , Linfoma no Hodgkin/patología , Masculino , Microscopía Electrónica de Transmisión , Microscopía Fluorescente , Persona de Mediana Edad , Mitosis/efectos de los fármacos , Recurrencia Local de Neoplasia , Antígeno Nuclear de Célula en Proliferación/metabolismo , ARN Neoplásico/biosíntesis , ARN Neoplásico/genética
2.
Biomed Pharmacother ; 56(9): 439-45, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12481980

RESUMEN

L-Arginine (Arg) is classified as an essential amino acid for birds, carnivores and young mammals and a conditionally essential amino acid for adults. It is converted by arginase to L-ornithine, a precursor of polyamines and urea, which is important in the urea cycle. Arg serves as a precursor for creatine, which plays an essential role in the energy metabolism of muscle, nerve and testis and accounts for Arg catabolism and for the synthesis of agmatine and proteins. Via its ability to increase growth hormone secretion it influences immune function. Depending on nutritional status and developmental stage, normal plasma Arg concentrations in humans and animals range from 95 to 250 micromol/l. Systemic or oral Arg administration has been shown to improve cardiovascular function and reduce myocardial ischemia in coronary artery disease patients. It reduces blood pressure and renal vascular resistance in essential hypertensive patients with normal or insufficient renal function. Although Arg plasma concentrations are not altered in hypercholesterolemic individuals, oral or intravenous Arg administration can reverse endothelial dysfunction in hypercholesterolemic patients and in cigarette smokers. The main importance of Arg is attributed to its role as a precursor for the synthesis of nitric oxide (NO), a free radical molecule that is synthesized in all mammalian cells from L-Arg by NO synthase (NOS). NO appears to be a major form of the endothelium-derived relaxing factor (EDRF). NO and EDRF share similar chemical and pharmacological properties and are derived from the oxidation of a terminal guanidine group of L-Arg. Various mechanisms have been implicated in the defect in vascular relaxation. These include, increased diffusional barrier for NO, L-Arg depletion, altered levels of reactive oxygen, inactivation of NO by superoxide anions (O2-). The independent reactions of O2-, NO and their reaction yielding peroxynitrite are critical in the initiation and maintenance of the atherosclerotic state and contribute to the defect in vasorelaxation. NO also plays a role as a neurotransmitter, mediator of immune response and as signaling molecule. The NO synthesized by iNOS in macrophages contributes to their cytotoxic activity against tumor cells, bacteria and protozoa. Our aim here is to review on some amino acids with high functional priority such as Arg and to define their effective activity in human health and pathologies.


Asunto(s)
Arginina/metabolismo , Arginina/uso terapéutico , Animales , Arginina/administración & dosificación , Arginina/fisiología , Enfermedad , Salud , Humanos
3.
Biomed Pharmacother ; 56(9): 446-57, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12481981

RESUMEN

Glutamine and glutamate with proline, histidine, arginine and ornithine, comprise 25% of the dietary amino acid intake and constitute the "glutamate family" of amino acids, which are disposed of through conversion to glutamate. Although glutamine has been classified as a nonessential amino acid, in major trauma, major surgery, sepsis, bone marrow transplantation, intense chemotherapy and radiotherapy, when its consumption exceeds its synthesis, it becomes a conditionally essential amino acid. In mammals the physiological levels of glutamine is 650 micromol/l and it is one of the most important substrate for ammoniagenesis in the gut and in the kidney due to its important role in the regulation of acid-base homeostasis. In cells, glutamine is a key link between carbon metabolism of carbohydrates and proteins and plays an important role in the growth of fibroblasts, lymphocytes and enterocytes. It improves nitrogen balance and preserves the concentration of glutamine in skeletal muscle. Deamidation of glutamine via glutaminase produces glutamate a precursor of gamma-amino butyric acid, a neurotransmission inhibitor. L-Glutamic acid is a ubiquitous amino acid present in many foods either in free form or in peptides and proteins. Animal protein may contain from 11 to 22% and plants protein as much as 40% glutamate by weight. The sodium salt of glutamic acid is added to several foods to enhance flavor. L-Glutamate is the most abundant free amino acid in brain and it is the major excitatory neurotransmitter of the vertebrate central nervous system. Most free L-glutamic acid in brain is derived from local synthesis from L-glutamine and Kreb's cycle intermediates. It clearly plays an important role in neuronal differentiation, migration and survival in the developing brain via facilitated Ca++ transport. Glutamate also plays a critical role in synaptic maintenance and plasticity. It contributes to learning and memory through use-dependent changes in synaptic efficacy and plays a role in the formation and function of the cytoskeleton. Glutamine via glutamate is converted to alpha-ketoglutarate, an integral component of the citric acid cycle. It is a component of the antioxidant glutathione and of the polyglutamated folic acid. The cyclization of glutamate produces proline, an amino acid important for synthesis of collagen and connective tissue. Our aim here is to review on some amino acids with high functional priority such as glutamine and to define their effective activity in human health and pathologies.


Asunto(s)
Ácido Glutámico/metabolismo , Glutamina/metabolismo , Animales , Enfermedad , Ácido Glutámico/química , Ácido Glutámico/toxicidad , Glutamina/química , Salud , Humanos
4.
Biomed Pharmacother ; 56(4): 200-7, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12109813

RESUMEN

Polyphenols are the most abundant antioxidants in our diets. The main classes of polyphenols are phenolic acids (mainly caffeic acid) and flavonoids (the most abundant in the diet are flavanols (catechins plus proanthocyanidins), anthocyanins and their oxidation products), which account for one- and two-thirds, respectively. Polyphenols are reducing agents, and together with other dietary reducing agents, such as vitamin C, vitamin E and carotenoids, referred to as antioxidants, protect the body's tissues against oxidative stress and associated pathologies such as cancers, coronary heart disease and inflammation. The biological properties, bioavailability, antioxidant activity, specific interactions with cell receptors and enzymes, are related to the chemical structure of polyphenols. It is, therefore, essential to know the nature of the main polyphenols ingested, their dietary origin, the amounts consumed in different diets, their bioavailability and the factors controlling their bioavailability.


Asunto(s)
Fenoles/química , Fenoles/uso terapéutico , Polímeros/química , Polímeros/uso terapéutico , Antioxidantes/química , Antioxidantes/farmacocinética , Antioxidantes/uso terapéutico , Disponibilidad Biológica , Enfermedad Coronaria/dietoterapia , Enfermedad Coronaria/metabolismo , Enfermedad Coronaria/prevención & control , Inducción Enzimática/efectos de los fármacos , Inducción Enzimática/fisiología , Flavonoides/química , Flavonoides/farmacocinética , Flavonoides/uso terapéutico , Humanos , Hidroxibenzoatos/química , Hidroxibenzoatos/farmacocinética , Hidroxibenzoatos/uso terapéutico , Inflamación/dietoterapia , Inflamación/metabolismo , Inflamación/prevención & control , Neoplasias/dietoterapia , Neoplasias/metabolismo , Neoplasias/prevención & control , Fenoles/farmacocinética , Polímeros/farmacocinética
8.
Chem Phys Lipids ; 113(1-2): 41-53, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11687226

RESUMEN

Mixed monolayers of GM(1) glycolipid and stearoyl-oleoyl-phosphatidylcholine (SOPC) or dipalmitoyl-phosphatidycholine (DPPC) phospholipids were studied by surface pressure measurements. The effects induced by GM(1) on the mean molecular areas of mixtures and DPPC phase transition were followed for GM(1) concentrations ranging from 1 to 20 mol.%. Under our experimental conditions, one main parameter influencing the behavior of phospholipid-GM(1) monolayers is the ionic strength of the subphase. Mixed monolayers are in a more expanded state on buffer than on pure water. This could be due to a change of GM(1) orientation at the interface. The interaction of wheat germ agglutinin (WGA), a lectin recognizing specifically GM(1), with these monolayers was quantified in terms of the Gibbs equation. Specific WGA-GM(1) interactions are clearly reduced in the presence of DPPC as compared with SOPC, probably because of the higher packing density of these monolayers. Phospholipid-GM(1) monolayers could also undergo some rearrangements induced by WGA binding.


Asunto(s)
Gangliósido G(M1)/metabolismo , Fosfatidilcolinas/química , Aglutininas del Germen de Trigo/metabolismo , Sitios de Unión , Relación Dosis-Respuesta a Droga , Gangliósido G(M1)/química , Humanos , Propiedades de Superficie , Termodinámica , Aglutininas del Germen de Trigo/química
11.
Biomed Pharmacother ; 55(6): 295-300, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11478579

RESUMEN

While the intensive virostatic combinations applied according to the conventional models (such as HAART), based only on the attacks of two HIV-1 targets, retrotranscriptase and protease, and applied in a long and continuous fashion, a) are notably toxic, b) do not correct completely the abnormal immunologic parameters, and c) are followed by particularly severe and poorly sensitive relapses in case of discontinuation, we propose to the 'AIDS treatment headquarters' to include in their failing strategy the two original features which we have included in the treatment of a cohort of a dozen patients, treatment applied at all but one AIDS stage. We attack one more HIV-1 target than the conventional protocols do, by adding inhibitors of integrase; we apply the combinations of virostatics, comprising inhibitors of the three targets, in short sequences (of 3 weeks), between which the analogues are changed inside each series. The first patient of the cohort started his treatment 8.5 years ago, and the entries of the others into it have been at random and not randomized. All patients are alive today and in excellent condition.


Asunto(s)
Complejo Relacionado con el SIDA/tratamiento farmacológico , Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Terapia Antirretroviral Altamente Activa , Inhibidores de Integrasa VIH/administración & dosificación , Inhibidores de Integrasa VIH/uso terapéutico , VIH-1/efectos de los fármacos , Complejo Relacionado con el SIDA/inmunología , Síndrome de Inmunodeficiencia Adquirida/inmunología , Acriflavina/administración & dosificación , Acriflavina/uso terapéutico , Animales , Antiinfecciosos Locales/administración & dosificación , Antiinfecciosos Locales/uso terapéutico , Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/uso terapéutico , Esquema de Medicación , Farmacorresistencia Viral , Elipticinas/administración & dosificación , Elipticinas/uso terapéutico , VIH-1/enzimología , Humanos , Inmunosupresores/administración & dosificación , Inmunosupresores/uso terapéutico
12.
Biomed Pharmacother ; 55(3): 127-9, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11325208

RESUMEN

Since the protein-specific antigen (PSA) test is systematically used in some countries for cancer detection, many asymptomatic and latent cancer patients are uselessly victims of anxiety, hormonotherapy, and impotence, when they are not demolished by surgery and/or radiotherapy's local and/or regional complications. We propose to conduct a study of dexamethasone as treatment of such latent, small and even wrongly diagnosed cases. Certainly it exerts at small doses a discrete hormonal effect. But it has an anti-growth factor effect, which may explain its often beneficial action on prostate cancer with resistance to androgen inhibitors.


Asunto(s)
Dexametasona/uso terapéutico , Disfunción Eréctil/etiología , Enfermedad Iatrogénica/prevención & control , Neoplasias de la Próstata/tratamiento farmacológico , Anciano , Humanos , Masculino , Persona de Mediana Edad , Antígeno Prostático Específico , Neoplasias de la Próstata/diagnóstico
13.
Biomed Pharmacother ; 55(3): 170-3, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11325215

RESUMEN

We have analyzed by morphological (TEM) and histochemical (TUNEL reaction) criteria the type of cell death occurring in one case of human multiple myeloma after hyperthermia. Samples of cells examined immediately at the end of two treatments with a 15-day interval showed a significant degeneration, mostly demonstrating features of apoptosis (cell shrinkage, DNA fragmentation, karyorrhexis). The possible causes of the lag period between heating and apoptosis onset-expression are discussed.


Asunto(s)
Apoptosis/fisiología , Hipertermia Inducida , Mieloma Múltiple/terapia , Anciano , Fragmentación del ADN , Humanos , Etiquetado Corte-Fin in Situ , Masculino , Microscopía Electrónica , Mieloma Múltiple/patología , Mieloma Múltiple/ultraestructura
14.
Biomed Pharmacother ; 55(1): 3-6, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11237282

RESUMEN

In the first part of the present editorial [1], we recalled experimental and clinical data demonstrating that 1) UV, via their effects on Langerhans cells, and 2) some so-called immunodepressive viruses, such as measles, lymphocytic choriomeningitis agents, and some animal retroviruses, via their action on dendritic cells, can induce tolerance in some conditions concerning immunologic parameters and/or the antigen(s). We present in this second part of the editorial a commentary on patients treated at the AIDS phase of HIV-1 infection for 3.5 to 8 years. Among them, one has been submitted before and at the beginning of our treatment, for a psoriasis, to a PUVA irradiation, at the dose of 214.5 J (spectrum 230-320). We were present at the end of this irradiation to see the disappearance of his blood CD4 and of his suppressor T cells. Comparing his data with those of other patients of the cohort similarly treated, we have found arguments to consider that this UV-victim patient has presented for the 6 years of his clinically excellent survival and still presents manifestations of immunologic tolerance towards a fraction of his HIV-1 population.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/inmunología , Dendritas/inmunología , Dendritas/virología , VIH/inmunología , Tolerancia Inmunológica , Células de Langerhans/inmunología , Células de Langerhans/efectos de la radiación , Humanos
15.
Biomed Pharmacother ; 55(9-10): 531-42, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11769962

RESUMEN

Children's acute lymphoid leukemia (ALL) chemotherapy started in 1948 with antimetabolites combined with steroids. It was enriched in 1959 with vincristine and cyclophosphamide and, in 1970, with daunomycin. It induced more and more apparently what were called complete remissions, and prolonged more and more the survivals without reducing however, until 1973, the (100%) mortality. It started to reduce it at the fifth year, to 20 and even 40% between 1973 and 1976, due to progressive and maximal intensification and duration of chemotherapy. It is in the same period that we proposed to apply in ALL remissions after relapses and in the first remissions of the most malignant type, allogeneic bone marrow grafts; we published the first success in human ALL in 1963, and clinically observed the same actions as those described experimentally: cytoablation of both leukemia and hematopoiesis, the latter being restored by the graft, whose reaction versus the residual neoplastic cells (called graft versus leukemia or GvL) appeared to be able to often eradicate them, at the cost however of a graft-versus-host reaction (both reactions sharing the same mechanism). One of us became a member of the Committee of the International Bone Marrow Transplant Registry, whose results showed the improvement in the prognosis of the aggressive form of ALL. The intensity and length established for chemotherapy for the most severe form of children's ALL have often been applied to the intermediary and to the least aggressive ones. The global 5-year survival increased to 60% between 1976 and 1984, and is around 80% today. But the registration of late debilitating or malignant effects of chemotherapy toxicities makes us wonder if some patients have not received an excessively intense and long application of cytostatics (often combined with ionizing radiations on CNS). In fact, the patients belonging to some HLA phenotypes (A33 and B17) have appeared to be especially often cured with active immunotherapy (killed leukemic cells and/or BCG), whose action was shown by specific cytotoxicity amplification, which was applied after short adjuvant chemotherapy, and hence is able to reduce the long chemotherapy incidence of debilitating or malignant late effects. Sakurai's group confirmed our absence of late relapses after ALL active immunotherapy, which contrasts with their risk after maintenance chemotherapy, whose minimal residual disease is a worrisome stumbling block to the cure.


Asunto(s)
Inmunoterapia Activa , Inmunoterapia Adoptiva , Leucemia Linfoide/terapia , Antineoplásicos/uso terapéutico , Niño , Enfermedad Crónica , Terapia Combinada , Resistencia a Antineoplásicos , Humanos , Inmunoterapia Activa/efectos adversos , Inmunoterapia Adoptiva/efectos adversos , Leucemia Linfoide/tratamiento farmacológico , Pronóstico
16.
Biomed Pharmacother ; 54(10): 475-8, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11130845
17.
Biomed Pharmacother ; 54(6): 287-90, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10989960

RESUMEN

Though it has not been described by the HIV1-AIDS consensual thinkers, we propose the thesis according to which some immunocyte populations or their interactions can achieve tolerance or split immunologic tolerance in patients suffering from this disease. The proposed concept is based on data registered: 1) after Langerhans cell local injury by UV irradiation in their physiologic localisations, the skin and mucosae: and 2) after systemic infections of dendritic cells by immunosuppressive viruses, including some animal retroviruses, measles, lymphocytic choriomeningitis viruses, and HIV1. We can describe both types or manifestations concerning local UV injury and systemic viral infection combined in an AIDS patient, who received a PUVA irradiation before and at the beginning of his virostatic treatment, which he has now successfully received for eight years. The conditions of this patient differ from those of non-UV victim patients of the cohort to which he belongs, for two reasons: 1) the numbers of both his CD4+ and his suppressor T cells have been reduced to near 0 after UV irradiation; and b) his viral load, which has been exponentially reduced, has not reached, after eight years, the asymptotic part of the VL curve, characterized by PCR non-assessable viral load, which the non-UV victims of the cohort have reached. We wonder if, in this patient, there do not coexist two sorts of immunologic phenomena: 1) one bound to CTL, the numbers of which are increased, whose cytotoxicity is added to the virostatic action; and 2) one bound to the virus attack restriction by an immunologic tolerance. Contrary to the cohort controls, in whom an allogenic skin graft was only accepted for 20 days, the graft of the same donor has been tolerated in the UV victim patient for 70 days. This patient will be discussed in the second part of this editorial: the first part is devoted to the description of several conditions in which Langerhans cell injury by UV, or dendritic cell infections by measles, lymphocytic choriomeningitis viruses or animal retroviruses are followed, not only by immunodepression manifestations, but by immunologic tolerance.


Asunto(s)
Células Dendríticas/virología , VIH-1/fisiología , Tolerancia Inmunológica , Células de Langerhans/efectos de la radiación , Virus de la Coriomeningitis Linfocítica/fisiología , Virus del Sarampión/fisiología , Animales , Células Dendríticas/fisiología , Humanos , Células de Langerhans/fisiología , Rayos Ultravioleta
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