RESUMEN
One prerequisite that radiotherapy (RT) and chemotherapy (CT) result in anti-tumor immune responses is triggering of immunogenic cell death forms such as necroptosis. The latter is inducible by inhibition of apoptosis with the pan-caspase inhibitor zVAD-fmk. The design of multimodal therapies that overcome melanoma's resistance to apoptosis is a big challenge of oncoimmunology. As hints exist that immune stimulation by hyperthermia (HT) augments the efficacy of melanoma therapies and that tumors can be sensitized for RT with zVAD-fmk, we asked whether combinations of RT with dacarbazine (DTIC) and/or HT induce immunogenic melanoma cell death and how this is especially influenced by zVAD-fmk. Necroptosis was inducible in poorly immunogenic B16-F10 melanoma cells and zVAD-fmk generally increased melanoma cell necrosis concomitantly with the release of HMGB1. Supernatants (SNs) of melanoma cells whose cell death was modulated with zVAD-fmk induced an upregulation of the activation markers CD86 and MHCII on macrophages. The same was seen on dendritic cells (DCs), but only when zVAD-fmk was added to multimodal tumor treatments including DTIC. DCs of MyD88 KO mice and DCs incubated with SNs containing apyrase did not increase the expression of these activation markers on their surface. The in vivo experiments revealed that zVAD-fmk decreases the tumor growth significantly and results in a significantly reduced tumor infiltration of Tregs when added to multimodal treatment of the tumor with RT, DTIC and HT. Further, a significantly increased DC and CD8+ T-cell infiltration into the tumor and in the draining lymph nodes was induced, as well as an increased expression of IFNγ by CD8+ T cells. However, zVAD-fmk did not further reduce tumor growth in MyD88 KO mice, mice treated with apyrase or RAG KO mice. We conclude that HMGB1, nucleotides and CD8+ T cells mediate zVAD-fmk induced anti-melanoma immune reactions in multimodal therapy settings.
Asunto(s)
Clorometilcetonas de Aminoácidos/uso terapéutico , Apoptosis/inmunología , Linfocitos T CD8-positivos/inmunología , Proteína HMGB1/metabolismo , Melanoma Experimental/patología , Animales , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Apirasa/uso terapéutico , Antígeno B7-2/biosíntesis , Antígeno B7-2/inmunología , Inhibidores de Caspasas/uso terapéutico , Línea Celular Tumoral , Quimioradioterapia , Terapia Combinada , Dacarbazina/uso terapéutico , Células Dendríticas/inmunología , Antígenos de Histocompatibilidad Clase II/biosíntesis , Antígenos de Histocompatibilidad Clase II/inmunología , Proteínas de Homeodominio/genética , Hipertermia Inducida , Interferón gamma/biosíntesis , Interferón gamma/inmunología , Activación de Linfocitos/inmunología , Macrófagos Peritoneales/inmunología , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/radioterapia , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Factor 88 de Diferenciación Mieloide/genética , Radiación Ionizante , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
A split plot experiment with 72 male pigs weighing 52.9 ± 0.39 kg (mean ± SEM) was conducted to examine AA partitioning and body protein deposition (PD) in response to increasing dietary sulfur amino acids (SAA) with or without immune system (IS) activation. The main plot was with and without IS activation, and 4 diets containing different amounts of standardized ileal digestible (SID) SAA (SAA to Lys ratios of 0.45, 0.55, 0.65 and 0.75) were the subplots. Activation of IS was achieved by intramuscular injection of Escherichia coli lipopolysaccharides (LPS; serotype 055:B5, Sigma; 30 µg/kg BW) every Monday and Thursday, with control pigs injected with sterile saline. Maximum body PD, measured by dual-energy X-ray absorptiometry (DXA), and minimum plasma urea content were achieved at SID SAA:Lys ratio of 0.55 in saline-injected pigs but were achieved at a SID SAA:Lys ratio of 0.75 in IS-activated pigs. Immune system activation increased rectal temperature (P < 0.05), plasma haptoglobin (1.1 vs. 2.0 mg/mL; P < 0.001), and the proportion of neutrophils (0.39 vs. 0.42; P < 0.05) and decreased serum albumin content (38.4 vs. 36.8 g/L; P < 0.01). Increasing dietary SAA had no effects on these variables. Immune system-activated pigs had lower levels of homocysteine (Hcy; P < 0.001) and a lower Ser content (P < 0.05). Results showed that increasing dietary SAA as DL-methionine in growing and/or finishing pigs altered plasma AA contents, and that use efficiency of the AA was improved when greater levels of SAA were supplemented in IS-activated pigs.
Asunto(s)
Aminoácidos/sangre , Alimentación Animal/análisis , Lipopolisacáridos/toxicidad , Proteínas/metabolismo , Porcinos/fisiología , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Composición Corporal , Dieta/veterinaria , Escherichia coli/metabolismo , Lipopolisacáridos/administración & dosificación , Masculino , Porcinos/crecimiento & desarrolloRESUMEN
A major myonecrotic zinc containing metalloprotease 'malabarin' with thrombin like activity was purified by the combination of gel permeation and anion exchange chromatography from T. malabaricus snake venom. MALDI-TOF analysis of malabarin indicated a molecular mass of 45.76 kDa and its N-terminal sequence was found to be Ile-Ile-Leu- Pro(Leu)-Ile-Gly-Val-Ile-Leu(Glu)-Thr-Thr. Atomic absorption spectral analysis of malabarin raveled the association of zinc metal ion. Malabarin is not lethal when injected i.p. or i.m. but causes extensive hemorrhage and degradation of muscle tissue within 24 hours. Sections of muscle tissue under light microscope revealed hemorrhage and congestion of blood vessel during initial stage followed by extensive muscle fiber necrosis with elevated levels of serum creatine kinase and lactate dehydrogenase activity. Malabarin also exhibited strong procoagulant action and its procoagulant action is due to thrombin like activity; it hydrolyzes fibrinogen to form fibrin clot. The enzyme preferentially hydrolyzes Aα followed by B subunits of fibrinogen from the N-terminal region and the released products were identified as fibrinopeptide A and fibrinopeptide B by MALDI. The myonecrotic, fibrinogenolytic and subsequent procoagulant activities of malabarin was neutralized by specific metalloprotease inhibitors such as EDTA, EGTA and 1, 10-phenanthroline but not by PMSF a specific serine protease inhibitor. Since there is no antivenom available to neutralize local toxicity caused by T. malabaricus snakebite, EDTA chelation therapy may have more clinical relevance over conventional treatment.
Asunto(s)
Quelantes/farmacología , Venenos de Crotálidos/antagonistas & inhibidores , Ácido Edético/farmacología , Hemorragia/tratamiento farmacológico , Metaloproteasas/antagonistas & inhibidores , Necrosis/tratamiento farmacológico , Mordeduras de Serpientes , Trimeresurus/fisiología , Animales , Antivenenos/química , Antivenenos/farmacología , Coagulación Sanguínea , Quelantes/química , Cromatografía en Gel , Creatina Quinasa/análisis , Creatina Quinasa/metabolismo , Venenos de Crotálidos/enzimología , Venenos de Crotálidos/toxicidad , Ácido Edético/química , Hemorragia/patología , Hemorragia/prevención & control , L-Lactato Deshidrogenasa/análisis , L-Lactato Deshidrogenasa/metabolismo , Masculino , Metaloproteasas/química , Metaloproteasas/aislamiento & purificación , Metaloproteasas/toxicidad , Ratones , Peso Molecular , Músculos/efectos de los fármacos , Músculos/patología , Necrosis/patología , Necrosis/prevención & control , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Zinc/metabolismoRESUMEN
Hyperthermia (HT)--heating the tumor in the range of 40.0- 44.0 °C--combined with radiation (RT) and/or chemotherapy (CT) is a well proven treatment for malignant tumors. The improvement of the techniques for monitoring and adapting of the desired temperatures even in deep seated tumors has led to a renaissance of, now quality-controlled, HT in multimodal tumor therapy approaches. Randomized clinical trials have shown improved disease-free survival and local tumor control without an increase in toxicity for the combined treatment. In this review, we will focus on biological rationales of HT comprising direct cytotoxicity, systemic effects, chemosensitization, radiosensitization, and immune modulation. The latter is a prerequisite for the control of recurrent tumors and micrometastases. Immunogenic tumor cell death forms induced by HT will be introduced. Modulations of the cytotoxic properties of chemotherapeutic agents by HT as well as synergistic effects of HT with RT will be presented in the context of the main aims of anti-tumor therapy. Furthermore, modern techniques for thermal mapping like magnet resonance imaging will be outlined. The effectiveness of HT will be demonstrated by reviewing recent clinical trials applying HT in addition to CT and/or RT. We conclude that hyperthermia is a very potent radio- as well as chemosensitizer, which fosters the induction of immunogenic dead tumor cells leading to local and in special cases also to systemic tumor control.
Asunto(s)
Hipertermia Inducida/métodos , Neoplasias/terapia , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Terapia Combinada/métodos , Terapia Combinada/tendencias , Humanos , Hipertermia Inducida/tendencias , Neoplasias/tratamiento farmacológico , Neoplasias/inmunología , Neoplasias/radioterapiaRESUMEN
This work studied interactions of uranium with pure organic compounds, such as glutathione, and more complex mixtures, such as humic acid and aqueous plant extracts. High performance liquid chromatography with UV absorption interfaced to inductively coupled plasma mass spectrometry sequential detection was used to detect organouranium complexes in a variety of soils and plant materials, indicating that nearly 100% of the uranium extracted from certain plant tissues was bound to organic ligands. In addition, soil sorption experiments indicated that humic acid generally decreased uranium sorption to soils and promoted subsequent desorption of uranium because of uranium partitioning to the organic phase. These experiments demonstrate that organic compounds influence the mobility and chemistry of uranium in the environment.
Asunto(s)
Monitoreo del Ambiente/métodos , Sustancias Húmicas/análisis , Compuestos Organometálicos/análisis , Desarrollo de la Planta , Contaminantes del Suelo/análisis , Uranio/análisis , Adsorción , Cromatografía Líquida de Alta Presión , Glutatión/química , Plantas/química , Solubilidad , Espectrofotometría AtómicaRESUMEN
Spirituality has become a construct of interest in American health care: however, there remains a limited understanding of how patients themselves describe spirituality and view its impact on their health and well-being. The purpose of this study was to identify and describe elements of patient-reported, health-related spirituality. A qualitative study utilized focus group interviews of 17 women with type 2 diabetes mellitus and 18 women with no self-identified illness. Purposeful sampling of participants who had prior experiences in healthcare settings, with or without a chronic illness, guided the sampling strategy. Editing analysis of the interview transcripts were coded into conceptual categories. Participant narratives were grouped into eight general categories: (1) change in functional status, (2) core beliefs, (3) medical/disease state information gathering and processing, (4) interpretation and understanding, (5) life scheme, (6) positive intentionality, (7) agency, and (8) subjective well-being. A change in functional status was the catalyst for two process-oriented categories; medical/disease state information gathering and processing, and the higher-order interpretation and understanding, or meaning making of life events. Core beliefs were sources that grounded and maintained an interpretative structure through which participants viewed their life events and positively framed their experiences. Life scheme described a heuristic framework through which all life events were viewed. Positive intentionality was participant belief in the capacity to execute a specific action that was required for a desired outcome. Participants tied the attitudes and practices of positive intentionality with agency, or the use or exertion of power through belief, practice, or community. Participants outlined both a positive affective and cognitive component of subjective well-being. Patients describe several interrelated elements and a process of events in their depiction of spirituality in healthcare settings. Patient-reported spirituality is predominantly a cognitive construct incorporating the domains of life scheme and positive intentionality.
Asunto(s)
Diabetes Mellitus , Estado de Salud , Espiritualidad , Adulto , Anciano , Enfermedad Crónica , Diabetes Mellitus/psicología , Femenino , Grupos Focales , Humanos , Persona de Mediana EdadRESUMEN
OBJECTIVES: The purpose of the study was to examine the value of right- and left-sided mapping to identify the site of tachycardia origin. BACKGROUND: Focal atrial tachycardia may originate from the vicinity of the atrioventricular node from either side of the interatrial septum. METHODS: In 16 patients undergoing radiofrequency catheter ablation of perinodal atrial tachycardia, activation mapping of the right and left side of the interatrial septum was performed. RESULTS: Atrial tachycardia originated from the right side of the interatrial septum in 10 patients (group A) and from the left side in 6 patients (group B). On the right side, earliest atrial activity preceded the onset of the P-wave by 49 +/- 15 ms in group A and by 38 +/- 8 ms in group B (NS), and it preceded the signal recorded from the right atrial appendage by 59 +/- 19 ms in group A and by 60 +/- 13 ms in group B (NS). On the left side, earliest activity preceded the onset of the P-wave by 27 +/- 16 ms in group A and by 51 +/- 6 ms in group B (<0.01), and it preceded the signal obtained from the right atrial appendage by 38 +/- 19 ms in group A and by 73 +/- 9 ms in group B (<0.01). Atrial tachycardias were successfully eliminated in all patients without impairment of atrioventricular conduction. During follow-up, two patients had a recurrence of tachycardia. CONCLUSIONS: Mapping of only the right side cannot exclude a left-sided origin. Therefore, mapping of both sides of the interatrial septum is required prior to ablation of focal atrial tachycardia originating from the vicinity of the atrioventricular node.
Asunto(s)
Nodo Atrioventricular/cirugía , Ablación por Catéter/métodos , Técnicas Electrofisiológicas Cardíacas/métodos , Tabiques Cardíacos/fisiopatología , Taquicardia Atrial Ectópica/cirugía , Adulto , Anciano , Electrocardiografía , Femenino , Estudios de Seguimiento , Atrios Cardíacos/diagnóstico por imagen , Atrios Cardíacos/fisiopatología , Atrios Cardíacos/cirugía , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Taquicardia Atrial Ectópica/diagnóstico por imagen , Taquicardia Atrial Ectópica/fisiopatologíaRESUMEN
11 beta-hydroxysteroid dehydrogenase (11 beta-OHSD) protects the non-selective renal mineralocorticoid receptor from the endogeneous glucocorticoid cortisol. Thus, drugs inhibiting 11 beta-OHSD might enhance urinary loss of potassium. In an attempt to find drugs inhibiting 11 beta-OHSD, 23 commonly used agents known to interfere with the potassium metabolism have been screened for inhibitory effect on 11 beta-OHSD. Furosemide appeared as the only inhibitor. Its inhibition constant (Ki) was 19.5 microM when kidney and 21.3 microM when liver microsomes were used as a source of 11 beta-OHSD. The type of inhibition was competitive. For confirmation that furosemide specifically inhibits 11 beta-OHSD, the complementary DNA (cDNA) of 11 beta-OHSD was transfected into COS-1 cells devoid of spontaneous expression of 11 beta-OHSD. In these cells, oxidation of corticosterone (Ki = 17.4 microM) and reduction of dehydrocorticosterone (Ki = 12.5 microM) was inhibited by furosemide. To establish whether this inhibition also occurs in vivo, the 11 beta-hydroxysteroid prednisolone was administered with and without furosemide to rats. The concentration ratio of prednisolone to its 11-ketometabolite prednisone increased in kidney and liver tissue after furosemide administration, indicating inhibition of 11 beta-OHSD. These data suggest that furosemide modulates in vivo the access of 11 beta-OH glucocorticoids to their target organs.