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1.
Phys Rev Lett ; 129(16): 161805, 2022 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-36306777

RESUMEN

We report on a blinded analysis of low-energy electronic recoil data from the first science run of the XENONnT dark matter experiment. Novel subsystems and the increased 5.9 ton liquid xenon target reduced the background in the (1, 30) keV search region to (15.8±1.3) events/(ton×year×keV), the lowest ever achieved in a dark matter detector and ∼5 times lower than in XENON1T. With an exposure of 1.16 ton-years, we observe no excess above background and set stringent new limits on solar axions, an enhanced neutrino magnetic moment, and bosonic dark matter.

2.
Phys Rev Lett ; 126(9): 091301, 2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33750173

RESUMEN

We report on a search for nuclear recoil signals from solar ^{8}B neutrinos elastically scattering off xenon nuclei in XENON1T data, lowering the energy threshold from 2.6 to 1.6 keV. We develop a variety of novel techniques to limit the resulting increase in backgrounds near the threshold. No significant ^{8}B neutrinolike excess is found in an exposure of 0.6 t×y. For the first time, we use the nondetection of solar neutrinos to constrain the light yield from 1-2 keV nuclear recoils in liquid xenon, as well as nonstandard neutrino-quark interactions. Finally, we improve upon world-leading constraints on dark matter-nucleus interactions for dark matter masses between 3 and 11 GeV c^{-2} by as much as an order of magnitude.

3.
Ann Oncol ; 29(12): 2288-2295, 2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-30304498

RESUMEN

Quality of life (QoL) is a relevant end point and a topic of growing interest by both scientific community and regulatory authorities. Our aim was to review QoL prevalence as an end point in cancer phase III trials published in major journals and to evaluate QoL reporting deficiencies in terms of under-reporting and delay of publication. All issues published between 2012 and 2016 by 11 major journals were hand-searched for primary publications of phase III trials in adult patients with solid tumors. Information about end points was derived from paper and study protocol, when available. Secondary QoL publications were searched in PubMed. In total, 446 publications were eligible. In 210 (47.1%), QoL was not included among end points. QoL was not an end point in 40.1% of trials in the advanced/metastatic setting, 39.7% of profit trials and 53.6% of non-profit trials. Out of 231 primary publications of trials with QoL as secondary or exploratory end point, QoL results were available in 143 (61.9%). QoL results were absent in 37.6% of publications in the advanced/metastatic setting, in 37.1% of profit trials and 39.3% of non-profit trials. Proportion of trials not including QoL as end point or with missing QoL results was relevant in all tumor types and for all treatment types. Overall, 70 secondary QoL publications were found: for trials without QoL results in the primary publication, probability of secondary publication was 12.5%, 30.9% and 40.3% at 1, 2 and 3 years, respectively. Proportion of trials not reporting QoL results was similar in trials with positive results (36.5%) and with negative results (39.4%), but the probability of secondary publication was higher in positive trials. QoL is not included among end points in a relevant proportion of recently published phase III trials in solid tumors. In addition, QoL results are subject to significant under-reporting and delay in publication.


Asunto(s)
Ensayos Clínicos Fase III como Asunto/normas , Oncología Médica/normas , Neoplasias/terapia , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto/normas , Humanos , Neoplasias/mortalidad , Neoplasias/psicología , Medición de Resultados Informados por el Paciente , Guías de Práctica Clínica como Asunto , Supervivencia sin Progresión , Proyectos de Investigación/normas
4.
J Viral Hepat ; 20(2): 113-21, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23301546

RESUMEN

Genetic factors can influence the outcome of antiviral therapy in chronic hepatitis C (HCV). We evaluated the role of interleukin-28B single nucleotide polymorphisms (SNPs) and inosine triphosphatase (ITPA) gene variants in HCV cirrhosis treated with Peg-Interferon and ribavirin. A prospective cohort of 233 patients with compensated cirrhosis received 1-1.5 µg/kg/week of Peg-Interferon alpha-2b plus 1000-1200 mg/day of RBV for 48 weeks. A sustained virologic response (SVR) was achieved in 27% of patients. On multivariate logistic analysis, the absence of oesophageal varices (OR 3.64 CI 95% 1.27-10.44 P = 0.016), infection with genotype 2 or 3 (OR 4.06, CI 95% 1.08-15.26, P = 0.038), C/C alleles of rs12979860 SNP (OR 7.04, CI 95% 2.40-20.72, P < 0.001) and rapid virologic response (RVR) (OR 78.29, CI 95% 16.07-381.29, P < 0.001) were independently associated with SVR. Patients who experienced post-treatment relapse received lower total doses of Peg-Interferon (52.0 ± 15.8 µg/kg vs 65.7 ± 13.3 µg/kg, P < 0.001) and lower total dose of RBV (3829 ± 1210 mg vs 4709 ± 954 mg, P < 0.001) than patients who achieved an SVR. ITPA variants predictive of high ITPase activity were associated with reduction of haemoglobin ≥3 g/dL in the first 4 weeks (P < 0.001), and with reduction of haemoglobin <10 g/dL (P = 0.03) on treatment. In conclusion, combination therapy with Peg-Interferon and RBV in patients with HCV cirrhosis must be guided by virus genotype, severity of portal hypertension, favourable IL-28B polymorphisms and ITPA variants, and RVR on treatment.


Asunto(s)
Antivirales/administración & dosificación , Várices Esofágicas y Gástricas/virología , Hepatitis C Crónica/genética , Interferón-alfa/administración & dosificación , Interleucinas/genética , Cirrosis Hepática/virología , Polietilenglicoles/administración & dosificación , Pirofosfatasas/genética , Ribavirina/administración & dosificación , Anciano , Anemia Hemolítica/inducido químicamente , Antivirales/efectos adversos , Relación Dosis-Respuesta a Droga , Quimioterapia Combinada , Femenino , Estudios de Asociación Genética , Genotipo , Hepacivirus/genética , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Interferón alfa-2 , Interferón-alfa/efectos adversos , Interferones , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Polietilenglicoles/efectos adversos , Polimorfismo de Nucleótido Simple , Estudios Prospectivos , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/efectos adversos , Ribavirina/efectos adversos , Análisis de Secuencia de ADN , Resultado del Tratamiento
5.
J Biol Regul Homeost Agents ; 26(3): 457-65, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23034265

RESUMEN

Mechanisms associated with reactivation of hepatitis B virus (HBV) in patients with occult HBV infection (OBI) remain unclear. In some cases immunosuppression is an enhancer of viral replication. However, not all patients with OBI who undergo immunosuppression experience reactivation. This study explores the role of viral heterogeneity as a determinant of occult HBV reactivation. HBV genotype, mutation patterns and quasispecies were assessed by sequencing the PreS/S region of 16 patients with OBI undergoing chemotherapy, 3 of whom experienced a OBI reactivation. The latter were also assessed at the time of reactivation. Phylogenetic analysis identified low nucleotide and amino acid diversity rates. There were no differences in the viral quasispecies, or common mutation patterns, detected between patients who underwent reactivation of OBI, and those who did not. Furthermore, upon reactivation, the quasispecies evolved towards a loss of most of the variants present during the initial OBI stage, probably representing the fittest version of the virus. The genetic variability of HBV alone did not account for the transition from occult to overt infection, which appears to be governed principally by the host immune response.


Asunto(s)
ADN Viral/genética , Variación Genética , Genotipo , Virus de la Hepatitis B/genética , Hepatitis B/genética , Huésped Inmunocomprometido , Análisis de Secuencia de ADN , ADN Viral/inmunología , Femenino , Hepatitis B/tratamiento farmacológico , Hepatitis B/inmunología , Virus de la Hepatitis B/inmunología , Humanos , Masculino , Estudios Retrospectivos
6.
J Viral Hepat ; 18(7): e372-80, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21692950

RESUMEN

The triglycerides × glucose (TyG) index is a recently proposed surrogate marker of insulin resistance (IR), calculated from fasting plasma triglyceride and glucose concentrations. We tested the host and viral factors associated with Tyg and homeostasis model assessment (HOMA) scores, comparing their associations with histological features and with sustained virological response (SVR) in patients with genotype 1 chronic hepatitis C(G1CHC). Three hundred and forty consecutive patients with G1CHC were considered. All had a liver biopsy scored by one pathologist for staging and grading (Scheuer), and graded for steatosis, which was considered moderate-severe if ≥30%. Anthropometric and metabolic measurements, including IR measured by both HOMA and TyG, were registered. By linear regression analysis, TyG was independently associated with waist circumference (WC), total cholesterol, presence of arterial hypertension, Log10 HCV-RNA and steatosis. Similarly, WC and steatosis were significantly associated with HOMA. Older age (OR, 1.036; 95%CI, 1.004-1.070, P = 0.02), higher WC (1.031; 1.004-1.060; P = 0.02) and higher TyG (11.496; 3.163-41.784; P < 0.001) were linked to moderate-to-severe steatosis (≥30%) by multiple logistic regression analysis. When TyG was replaced by HOMA-IR in the model, the latter remained significantly associated with steatosis ≥30% (1.237; 1.058-1.448; P = 0.008). Receiver operating characteristic curves showed a similar performance of TyG (AUC 0.682) and HOMA-IR (AUC 0.699) in predicting moderate-severe steatosis. No independent associations were found between both TyG and HOMA and fibrosis or SVR. In patients with G1CHC , TyG, an easy-to-calculate and low-cost surrogate marker of IR, is linked to liver steatosis and shows an independent association with viral load.


Asunto(s)
Glucemia , Hepatitis C Crónica/sangre , Hepatitis C Crónica/virología , Homeostasis , Resistencia a la Insulina , Triglicéridos/sangre , Adulto , Anciano , Antivirales/uso terapéutico , Índice de Masa Corporal , Quimioterapia Combinada , Hígado Graso , Femenino , Hepacivirus/genética , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Interferón-alfa , Masculino , Persona de Mediana Edad , Polietilenglicoles , ARN Viral/sangre , Proteínas Recombinantes , Ribavirina , Resultado del Tratamiento , Carga Viral
7.
Eur Phys J C Part Fields ; 81(4): 337, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34720714

RESUMEN

The selection of low-radioactive construction materials is of utmost importance for the success of low-energy rare event search experiments. Besides radioactive contaminants in the bulk, the emanation of radioactive radon atoms from material surfaces attains increasing relevance in the effort to further reduce the background of such experiments. In this work, we present the 222 Rn emanation measurements performed for the XENON1T dark matter experiment. Together with the bulk impurity screening campaign, the results enabled us to select the radio-purest construction materials, targeting a 222 Rn activity concentration of 10 µ Bq / kg in 3.2 t of xenon. The knowledge of the distribution of the 222 Rn sources allowed us to selectively eliminate problematic components in the course of the experiment. The predictions from the emanation measurements were compared to data of the 222 Rn activity concentration in XENON1T. The final 222 Rn activity concentration of ( 4.5 ± 0.1 ) µ Bq / kg in the target of XENON1T is the lowest ever achieved in a xenon dark matter experiment.

8.
J Exp Med ; 167(6): 1981-6, 1988 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-2968435

RESUMEN

The therapeutic efficacies of ART-18, ART-65, and OX-39, mouse antibodies of IgG1 isotype recognizing distinct epitopes of the p55 beta chain of the rat IL-2-R molecule, were probed in LEW rat recipients of (LEW X BN)F1 heterotopic cardiac allografts (acute rejection in untreated hosts occurs within 8 d). A 10-d course with ART-18 prolongs graft survival to approximately 21 d (p less than 0.001). Therapy with ART-65, but not with OX-39, was effective (graft survival approximately 16 and 8 d, respectively). Anti-IL-2-R mAb treatment selectively spared T cells with donor-specific suppressor functions; the CD8+ (OX8+ W3/25-) fraction from ART-18-modified recipients, and primarily the CD4+ (W3/25+ OX8-) subset from ART-65-treated hosts conferred unresponsiveness to naive syngeneic rats after adoptive transfer, increasing test graft survival to approximately 16 and 45 d, respectively. Concomitant administration of ART-18 and ART-65 to recipient animals in relatively low doses exerted a strikingly synergistic effect, with 30% of the transplants surviving indefinitely and 50% undergoing late rejection over 50 d. These studies provide evidence that anti-IL-2-R mAbs selectively spare phenotypically distinct T cells with suppressor functions. The data also suggest that in vivo targeting of functionally different IL-2-R epitopes may produce synergistic biological effects.


Asunto(s)
Interleucina-2/fisiología , Receptores Inmunológicos/inmunología , Linfocitos T Reguladores/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Especificidad de Anticuerpos , Reacciones Antígeno-Anticuerpo , Terapia de Inmunosupresión , Ratas , Receptores de Interleucina-2 , Linfocitos T/clasificación , Linfocitos T/inmunología
9.
Int J Cardiol ; 257: 243-246, 2018 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-28918896

RESUMEN

BACKGROUND: Mobilization of endothelial progenitor cells (EPCs) into circulation from bone marrow in patients with acute myocardial infarction has strong scientific evidence; less is known about EPC mobilization in patients with stable coronary artery disease (CAD). The aim of this study was to investigate the association of stable ischemic heart disease with EPC levels in tissue and blood. METHODS: Fifty-five consecutive patients admitted to a single treatment center for valve or coronary artery bypass grafting (CABG) surgeries were included in the study. Blood samples were collected in the morning before surgery and analyzed by flow-cytometry to determine peripheral EPC levels (EPC/ml). Tissue EPC (CD34+VEGFR2+) levels were assessed on a right atrial appendage segment. RESULTS: Mean age was 76±5years, 48% were men, and 53% had CAD The number of CD34+ VEGFR2+ cells in the tissue of patients with CAD was significantly higher (p<0.005) and circulating EPC showed a tendency to be reduced by approximately 20% in peripheral blood of patients with CAD when compared to those without CAD. CONCLUSION: Patients with stable CAD had higher EPC density values (EPC/mm2) and were more likely to have lower EPC blood levels when compare with normal controls.


Asunto(s)
Células Progenitoras Endoteliales/fisiología , Isquemia Miocárdica/sangre , Isquemia Miocárdica/cirugía , Anciano , Anciano de 80 o más Años , Procedimientos Quirúrgicos Cardíacos/métodos , Procedimientos Quirúrgicos Cardíacos/tendencias , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/cirugía , Femenino , Citometría de Flujo/métodos , Citometría de Flujo/tendencias , Humanos , Masculino , Isquemia Miocárdica/diagnóstico por imagen
10.
Transfus Clin Biol ; 14(6): 542-50, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18434227

RESUMEN

The treatment of thalassemia is still essentially based on continuous transfusion supporting using red cell concentrates (RCC) prepared in different ways. For patients with sickle-cell disorders, either urgent or chronic red blood cell transfusion therapy, is widely used in the management of sickle cell disease (SCD) because it reduces HbS level and generally prevents recurrent vaso-occlusive disease (VOD). Recently, the introduction of pre-storage filtration to remove leukocytes and the use of techniques for multicomponent donation have increased the types of blood components available for transfusion purposes. The clinical effects of different types of blood components in thalassaemic and sickle-cell patients have not been extensively studied so far. We evaluated the impact of the various different blood components currently available on transfusion needs, transfusion intervals and adverse reactions in order to determine which is the most advantageous for transfusion-dependent thalassaemic and sickle-cell patients followed in our centre. We believe that the optimal characteristics of the RCC are aged less than 10 days from time of collection; Hb content greater than 56 g per unit; Hct: 55-60%; volume (including additive) 300 mL+/-20%; leucodepleted to less than 200,000 leukocytes per unit; low cytokine content (achievable by pre-storage filtration carried out between two and 24 hours after the collection); lack of microaggregates (achievable by pre-storage filtration or filtration in the laboratory) and protein content less than 0.5 g per unit for patients allergic to plasma proteins (achievable with manual or automated washing). It is still recommended that the blood transfused should be as fresh as possible, compatible with the centre's product availability and the centre's organisation should be continuously adapted to this aim. We always transfuse blood within 10 days of its collection, respecting Rh and Kell system phenotypes. Pre-storage filtration is strongly recommended, both in order to prevent adverse reactions through the marked leucodepletion (less than 200,000 leukocytes per unit) and for a better standardisation of the final product, including the certainty that the product does not contain clots, an assurance that bed-side filtration cannot give. The RCC should be produced using a method causing as little as possible stress to the red cell membrane. The use of RCC with a high content of Hb (less than 56 g per unit) is strongly recommended, because our study clearly shows that this reduces the number of exposures to donors and the number of accesses to hospital, thus improving the patient's quality of life.


Asunto(s)
Anemia de Células Falciformes/terapia , Eliminación de Componentes Sanguíneos/métodos , Transfusión de Eritrocitos/métodos , Talasemia/terapia , Adolescente , Adulto , Separación Celular , Transfusión de Eritrocitos/efectos adversos , Humanos , Persona de Mediana Edad , Plasmaféresis
11.
Biomed Pharmacother ; 60(8): 453-7, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16930933

RESUMEN

BACKGROUND: Treatment of oxidative stress-related pathologies is a possible therapeutical strategy for the future. Natural product with antioxidant properties could trigger this goal. The aim of this in vitro study was to assess the antioxidant activity of the natural product ergothioneine (EGT), a compound of plant origin, which is assimilated and conserved by mammals in erythrocytes, kidney, seminal fluid and liver. METHODS: We measured the antioxidant activity of EGT as its ability to antagonize the oxidation of alpha-keto-gamma-methiolbutyric acid (KMBA) by hydroxyl radical, peroxyl radicals and peroxynitrite. The results are expressed as total oxyradical scavenging capacity (TOSC) units. Glutathione (GSH), uric acid and 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (trolox), the water-soluble analog of vitamin E, were used as the reference antioxidants. RESULTS: EGT was the most active scavenger of free radicals as compared to classic antioxidants as GSH, uric acid and trolox. In particular, the highest antioxidant capacity exhibited by EGT vs. peroxyl radicals (5.53 +/- 1.27 units) resulted 25% higher than the value obtained with the reference antioxidant trolox (4.4 +/- 0.6 units, P < 0.01). The scavenging capacity of EGT towards hydroxyl radicals (0.34 +/- 0.09 units) was 60% higher, as compared to uric acid (0.21 +/- 0.04 units, P < 0.001), which represent the reference antioxidant vs. hydroxyl radicals. Finally, EGT showed the highest antioxidant activity also towards peroxynitrite (5.2 +/- 1.0 units), with a scavenging capacity 10% higher than that of uric acid (4.7 +/- 0.9 units, P < 0.05). CONCLUSIONS: This study showed that EGT has potent intrinsic anti-hydroxyl, anti-peroxyl and anti-peroxynitrite radicals antioxidant activity, as compared to classic molecules with antioxidant capacity as GSH, trolox and uric acid. This appears of interest, given the increasing use of non-vitamins cocktails for therapeutical approaches to many oxidative-induced pathologies.


Asunto(s)
Cromanos/química , Ergotioneína/química , Depuradores de Radicales Libres/química , Glutatión/química , Ácido Úrico/química , Butiratos/química , Oxidación-Reducción , Compuestos de Sulfhidrilo
12.
Transplantation ; 45(1): 162-8, 1988 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3276045

RESUMEN

We have analyzed the adjunctive effect of subtherapeutic doses of cyclosporine (CsA, 1.5 mg/kg/day x 7 or 14 days) on cardiac allograft survival in actively and passively enhanced rats. This CsA dose, one tenth of the effective dose, when administered after, but not before, transplantation into enhanced hosts produced permanent graft acceptance; cardiac allografts survive c. 25 days in recipients enhanced only and 1 week in untreated animals. Adoptive transfer of spleen T cells of OX8+ or W3/25+ phenotype from long-term (greater than 200 days) graft recipients prolonged donor-specific test graft survival in naive rats (c. 16 days and c. 14 days, respectively, P less than 0.001) and delayed rejection in reconstituted B rats from 7 days to 21-23 days (P less than 0.001). Indeed, both T subsets were separately equally potent and with no overlap responsible for the suppressor activity. The phenotypic profile of the immune cells in the maintenance phase of enhanced or enhanced + CsA-treated recipients was comparable to naive or isografted controls as demonstrated by flow cytometry and immunohistologic studies. Furthermore, the activation status of the graft infiltrate in long-term survivors was similar regardless of the initial immunosuppressive protocol. CsA contributed selectively to the enhancing regimen in the induction phase of unresponsiveness, diminishing the cellularity of graft infiltrate and preventing intragraft T cell activation. These studies stress synergy between subtherapeutic doses of CsA and immunologic active/passive enhancement, 2 immunosuppressive modalities that spare T cells with suppressor capabilities but differ in the inhibition of T helper cell activation.


Asunto(s)
Ciclosporinas/administración & dosificación , Refuerzo Inmunológico de Injertos , Supervivencia de Injerto , Trasplante de Corazón , Animales , Supervivencia de Injerto/efectos de los fármacos , Sueros Inmunes/administración & dosificación , Inmunización Pasiva , Masculino , Miocardio/patología , Ratas , Ratas Endogámicas BN/inmunología , Ratas Endogámicas Lew/inmunología , Linfocitos T/inmunología , Linfocitos T/trasplante , Trasplante Homólogo
13.
Transplantation ; 47(1): 11-6, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2463699

RESUMEN

A panel of five mouse mAbs recognizing 4 distinct epitopes (R1-4) of the rat 55kD IL-2R molecule were tested for their influence on acute rejection (8 days) of (LEWxBN)F1 cardiac allografts in LEW hosts. IL-2R1 targeted therapy with ART-18 (IgG1, inhibits IL-2-dependent responses) prolonged graft survival to ca.21 days. IL-2R2 is recognized by ART-65 and ART-75, mAbs that do not inhibit T cell growth. Treatment with ART-65 (IgG1) but not ART-75 (IgG2a) abrogated acute rejection (ca. 16 days and 9 days, respectively). ART-35, an anti-IL-2R3 mAb (IgG1, does not inhibit T cell function) extended graft survival marginally to ca. 12 days. Finally, therapy with OX-39, (anti-R4 IgG1 mAb, inhibits IL-2 binding, but not IL-2-driven growth) was completely ineffectual. Simultaneous targeting of two IL-2R epitopes increased the therapeutic index synergistically (ART-18 [R1] + ART-65 [R2]--60% permanent graft acceptance), additively (ART-75 [R1] + ART-35 [R3]--graft survival ca. 18 days), or did not improve further graft survival at all (ART-18 [R1] + OX-39 [R4]--graft survival ca. 18 days). Thus, the cellular targeting patterns and isotype of mAbs are crucial: (1) targeting at functionally distinct epitopes controls rejection most effectively; (2) IgG1 and IgG2b mAbs are more influential in vivo than IgG2a, data supported by the studies employing the family of ART-18 isotype switch variants. Treatment with anti-IL-2R mAb did not depress Ts activity as tested both in vitro and in vivo. Sparing of putative Ts by mAb is also shown by thymectomy of graft recipients before or during ART-18 therapy, which shortened graft survival to 13-15 days; thymectomy after ART-18 therapy did not influence graft survival. However, infusion of IFN-gamma recreated classic acute rejection within 10 days in otherwise longstanding cardiac allografts in ART-18 treated hosts. Upregulation of MHC class II antigen and IL-2R expression seems to be primarily responsible for this striking biological effect of IFN-gamma in vivo.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Trasplante de Corazón , Receptores de Interleucina-2/inmunología , Animales , Afinidad de Anticuerpos , Epítopos , Isotipos de Inmunoglobulinas/inmunología , Terapia de Inmunosupresión/métodos , Ratas , Ratas Endogámicas , Timectomía
14.
Transplantation ; 51(2): 300-5, 1991 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1825240

RESUMEN

UNLABELLED: LBNF1 cardiac allografts (Tx) are rejected within 36 hr in LEW rats sensitized with BN skin Tx 7 days earlier, compared to 8-day rejection in unmodified hosts. Treatment with cyclosporine or ART-18, an anti-interleukin 2 receptor (IL-2[R]) mAb monoclonal antibody, abrogates accelerated rejection and prolongs mean Tx survival to 42 days and 16 days, respectively. ART-18 given in concert with subtherapeutic dose of CsA extends survival to 25 days. These studies were designed to dissect the early mechanisms leading to ART-18 and/or CsA-mediated abrogation of accelerated Tx injury. No effect of concomitant mAb administration upon CsA through levels was noted in Tx recipients conditioned with both modalities. The beneficial effect of ART-18+CsA treatment was also unrelated to CsA-induced diminished host responses to mAb, as shown by ELISA. In the biodistribution studies 125I-labeled ART-18 accumulated preferentially into host lymphoid tissues and Tx itself and away from the blood. In animals that were concomitantly given "cold" CsA, the clearance of labeled ART-18 from the blood increased further, as did mAb sequestration into the Tx. The sensitized hosts developed high titers of complement-dependent cytotoxic (CDC) antibodies, which peaked at the time of actual Tx loss. ART-18 or CsA alone inhibited CDC, whereas combined therapy decreased further the humoral effects of sensitization. The cell-mediated lymphocytotoxicity assay revealed a similar pattern. CsA, ART-18, and combination therapy each modulated the deposition of IgG, IgM, and C3 in Tx, as shown by immunohistology. However, only CsA or ART-18+CsA therapy abolished or markedly decreased elaboration of IL-2, interferon gamma, and tissue necrosis factor alpha. IN CONCLUSION: (1) the adjunctive low dose of CsA potentiates the inhibitory effects of ART-18 upon humoral and cellular responses, leading to accelerated rejection of cardiac Tx in presensitized rats; (2) the synergistic interaction between both modalities that results in the inhibition of lymphokine production is critical and correlates with long-term Tx survival; (3) the biodistribution patterns of mAb are important--an increased blood level of mAb does not necessarily translate into its higher therapeutic efficacy.


Asunto(s)
Ciclosporinas/farmacología , Rechazo de Injerto/efectos de los fármacos , Trasplante de Corazón/inmunología , Subgrupos Linfocitarios/inmunología , Receptores de Interleucina-2/inmunología , Animales , Anticuerpos Antiidiotipos/biosíntesis , Anticuerpos Monoclonales/uso terapéutico , Ciclosporinas/sangre , Supervivencia de Injerto , Inmunidad , Inmunidad Celular , Isoanticuerpos/inmunología , Recuento de Leucocitos , Prueba de Cultivo Mixto de Linfocitos , Masculino , Ratas , Ratas Endogámicas , Receptores de Interleucina-2/farmacocinética , Distribución Tisular
15.
J Nucl Med ; 34(7): 1175-83, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8315499

RESUMEN

Previous studies have demonstrated the tumor-targeting potential of radioiodinated 5-iodo-2'-deoxyuridine (IUdR) in experimental animal models following direct intratumoral or intracavitary administration. The aim of this study was to measure the tumor uptake and metabolic fate of 5-[125I]iodo-2'-deoxyuridine ([125I]UdR) in humans after a single intratumoral injection. Ten patients with colorectal cancer were injected intratumorally with [125I]UdR) (0.24-3.9 MBq) during endoscopy 24 hr before ablative surgery. Blood and urine samples were collected up to 72 hr after [125I]UdR injection. Following resection, the radioactivity in the tumor and the surrounding tissues was measured in a gamma counter, and microautoradiography was performed on semi-thin tissue sections to assess localization of the radiopharmaceutical at the cellular level. An average of 0.234% of the injected dose was present per gram of tumor (range 0.009-0.918, median value 0.147), and tumor-to-nontumor radioactivity incorporation ratios were high for colonic mucosa when the nontumor tissue was taken at 1 cm (mean 629, range 27-2391) and 15 cm (mean 2387, range 122-12674) from the injection site. Microautoradiography confirmed these high tumor-to-nontumor ratios and demonstrated localization of [125I]UdR in the tumor cell nuclei. These results suggest that radioiodinated IUdR might have potential as a tumor-targeting agent in humans, provided homogeneous intratumoral distribution of the radiopharmaceutical by a suitable route of loco-regional administration can be achieved.


Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Neoplasias Colorrectales/diagnóstico por imagen , Idoxuridina , Radioisótopos de Yodo , Radioinmunodetección , Anciano , Anciano de 80 o más Años , Autorradiografía , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Inyecciones Intralesiones , Masculino , Persona de Mediana Edad
16.
J Nucl Med ; 37(4 Suppl): 22S-25S, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8676199

RESUMEN

UNLABELLED: We previously showed the tumor-targeting potential of the 125I-labeled thymidine analog 5-iodo-2'-deoxyuridine (IUdR) injected intratumorally in patients with high tumor-cell kinetics. In this study, we evaluated the tumor incorporation of [123I]IUdR infused intra-arterially in patients with liver metastases from colorectal cancer. METHODS: Iodine-123-IUdR (110-300 MBq, 3-8 mCi, specific activity, 150-200 Ci/mumole) was infused into the hepatic artery of 16 patients with inoperable liver metastases over 30-45 min through a permanent intra-arterial catheter. A dynamic sequence during infusion, spot images, whole-body scans and SPECT acquisitions were recorded up to 42 hr. Blood and urine samples were obtained for biodistribution and HPLC analyses. RESULTS: In the 14 patients with adequate tumor perfusion patterns, tumor uptake reached 2%-17.6% ID at the end of infusion. After a washout phase that lasted 18-20 hr, incorporated radioactivity remained steadily associated with the tumor lesions until at least 42 hr after infusion (about 1.4%-11.1% ID). HPLC analysis indicated a virtually 100% first-pass hepatic deiodination of unincorporated [123I]IUdR (about 80%-95% ID recovered in the 42-hr urine). No significant uptake was detected in the bone marrow or in other normal dividing tissues. CONCLUSION: These results encourage further studies to enable dosimetric estimates, optimization of dose regimens, and examination of the therapeutic potential of Auger-electron-emitter-labeled IUdR in cancer therapy utilizing this type of approach.


Asunto(s)
Neoplasias Colorrectales/patología , Idoxuridina/uso terapéutico , Radioisótopos de Yodo/uso terapéutico , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundario , Anciano , Cromatografía Líquida de Alta Presión , Femenino , Arteria Hepática , Humanos , Idoxuridina/administración & dosificación , Idoxuridina/farmacocinética , Infusiones Intraarteriales , Radioisótopos de Yodo/administración & dosificación , Radioisótopos de Yodo/farmacocinética , Neoplasias Hepáticas/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Cintigrafía , Dosificación Radioterapéutica
17.
Aliment Pharmacol Ther ; 15(7): 953-8, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11421869

RESUMEN

BACKGROUND: Therapy of chronic hepatitis C non- responders to interferon monotherapy with standard doses of interferon plus ribavirin is usually ineffective. AIM: To evaluate the efficacy and tolerability of high-dose prolonged combination retreatment in non- responder patients. METHODS: Patients were retreated for 6 months with 6 MU alphaIFN on alternate days and 1000 or 1200 mg/day ribavirin. HCV-RNA negative patients continued therapy for an additional 6 months. RESULTS: Forty patients (29 males, mean age 49.7 years, 34 genotype 1b, 11 with F3 fibrosis) were treated. At 6 months, 20 (50%) patients were HCV-RNA negative but six of them discontinued therapy because of adverse events. A sustained response was achieved in 28% of patients (11/40). A sustained response was more frequent among patients with genotype non-1b than in those with genotype 1b (67 vs. 21%, P=0.005) and clearance of HCV-RNA in the first 3 months had a high predictive value for sustained response (100% of sustained responders vs. 24% of non-responders, P=0.0001). CONCLUSIONS: High-dose prolonged combination therapy in non-responders to IFN monotherapy leads to a higher rate of sustained response than the standard combination regimen. Tolerability may be a rate-limiting factor. Maximal effectiveness can be predicted in patients with non-1b genotype and in those who clear HCV-RNA soon after starting retreatment.


Asunto(s)
Antivirales/farmacología , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/farmacología , Ribavirina/farmacología , Adulto , Antivirales/administración & dosificación , Antivirales/uso terapéutico , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Resistencia a Medicamentos , Quimioterapia Combinada , Femenino , Fibrosis , Genotipo , Hepatitis C Crónica/patología , Humanos , Interferón-alfa/administración & dosificación , Interferón-alfa/uso terapéutico , Masculino , Persona de Mediana Edad , ARN Viral/análisis , Ribavirina/administración & dosificación , Ribavirina/uso terapéutico , Resultado del Tratamiento
18.
Leuk Lymphoma ; 22(5-6): 473-81, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8882961

RESUMEN

The topography of and the area covered by tenascin, laminin and type IV collagen (all components of the subendothelial basement membrane), and the microvessel area (an index of angiogenesis), as evaluated with factor VIII, were investigated immunohistochemically in 61 B-cell non-Hodgkin's lymphomas (B-NHL) and 30 benign lymphadenopathies as controls. The three components were located in the microvessels and in a microvessel-bound stromal reticular network, the expression of tenascin being always more extended and finer than the other components. Of the lymphadenopathies, reactive and atypical lymphoid hyperplasias showed vessels and stromal network in the interfollicular zone only, whereas in Castleman's and angioimmunoblastic forms these structures were widely scattered in the tissue, and the area of the three components and that of the microvessels were significantly larger. Of the low-grade B-NHL, follicular subtypes had vessels and stromal network confined to the interfollicular inflammatory zone, but not in tumor follicles, whereas these structures were irregularly distributed throughout the small lymphocytic subtype. The levels of areas in low-grade B-NHL overlapped those of Castleman's and angioimmunoblastic lymphadenopathies. Among the intermediate-grade tumors, the follicular subtype resembled the follicular tumors, and the diffuse subtypes displayed vessels and stromal network throughout the tissue in close association with the neoplastic cells, and with significant increments of both the tenascin and the microvessel areas, but with a significant reduction of both the laminin and the type IV collagen areas. Distribution was similar in high-grade B-NHL, but tenascin and microvessel area variations, on the one hand, and those of laminin and type IV collagen areas were still more apparent than in the intermediate-grade. A high correlation was demonstrated in all groups of tissues between tenascin and microvessel area. In addition, in the diffuse intermediate-grade and high-grade B-NHL highly immature vessels were frequently detected by ultramicroscopy. The results show that tenascin expression and angiogenesis are closely related, and that both increase in function of tumor malignancy. Unlike laminin and type IV collagen, tenascin is associated with highly immature vessels in B-NHL. We suggest that tenascin expression and angiogenesis are governed by the B-NHL-associated inflammatory infiltrate, as well as by the B-NHL cells, particularly in more malignant tumors.


Asunto(s)
Linfoma de Células B/patología , Linfoma de Células B/fisiopatología , Neovascularización Patológica/metabolismo , Tenascina/biosíntesis , Endotelio Vascular/patología , Endotelio Vascular/ultraestructura , Femenino , Humanos , Inmunohistoquímica , Ganglios Linfáticos/metabolismo , Ganglios Linfáticos/patología , Enfermedades Linfáticas/metabolismo , Enfermedades Linfáticas/patología , Linfoma de Células B/metabolismo , Linfoma de Células B/ultraestructura , Masculino , Estadificación de Neoplasias , Neovascularización Patológica/patología , Análisis de Regresión
19.
Int J Antimicrob Agents ; 16(3): 373-8, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11091068

RESUMEN

In patients with chronic hepatitis C and HIV infection, responsiveness to the standard schedule of alpha-interferon (IFN) is unsatisfactory. To quantify the effectiveness of tailoring IFN dosage according to HCV viral load under treatment, we enrolled 41 patients (M/F 32/9) chronically coinfected by HCV and HIV with chronic liver disease. All were former i.v. drug addicts, with a mean age of 32+/-4 years, and had clinical and histological evidence of chronic hepatitis (10% with cirrhosis). The CDC stage was A1 in five, A2 in 14, A3 in eight, B2 in eight, B3 in three and C3 in three. Twenty four patients were on triple therapy with protease inhibitors, 11 were on two-drug anti-HIV regimens and three were untreated. IFN (alphan1 interferon) was started at 3 MU tiw and increased at 6 MU tiw at 4 weeks if serum HCV-RNA had not dropped by at least 50%. IFN was stopped at 24 weeks in non-responders. Eleven patients received a dose increase (total IFN dose at 24 weeks 396 MU), while 16 did not increase the initial dose (total IFN dose at 24 weeks 216 MU). Fourteen subjects stopped within the first weeks due to relapse of drug abuse (ten) or subjective intolerance (four). ALT and HCV-RNA levels were markedly decreased at week 4, and this reduction lasted up to 24 weeks. However only one patient had a complete biochemical and virological end-of-treatment response, which was maintained over a 24 weeks post-therapy follow-up. All other patients relapsed to baseline ALT and HCV-RNA values after stopping IFN. HIV viral load was slightly reduced under IFN therapy, while CD4 counts were unaffected. We conclude that raising the dose of IFN dose not eradicate HCV in most HIV-infected patients, even when HIV is well controlled by treatment. HCV viraemia and necroinflammation are temporarily suppressed by IFN, but the relevance of these surrogate endpoints to progression of liver disease and to survival cannot be assessed.


Asunto(s)
Antivirales/uso terapéutico , Infecciones por VIH/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Adulto , Antivirales/efectos adversos , Recuento de Linfocito CD4 , Femenino , VIH/efectos de los fármacos , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Hepacivirus/efectos de los fármacos , Hepatitis C Crónica/etiología , Humanos , Interferón-alfa/efectos adversos , Masculino , Cooperación del Paciente , Trastornos Relacionados con Sustancias/complicaciones , Resultado del Tratamiento , Carga Viral
20.
J Chromatogr A ; 778(1-2): 219-24, 1997 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-9299735

RESUMEN

The glycosides in mono-, di- and trihydroxylated terpene and norisoprenoid alcohols and also those in the related shikimate pathway have been isolated on C18 reversed-phase cartridges and then fractionated into classes of different polarity at increasing percentages of methanol. The benzyl alcohol glycosides are the most polar, while those of terpene monohydroxylated alcohols and geranic acid are the least polar. The terpene diols, linalool furanoid and pyranoid oxides and also norisoprenoid precursors show intermediate polarity and separate into well defined fractions according to their polarity.


Asunto(s)
Frutas/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Glicósidos/análisis , Vino/análisis , Butadienos/análisis , Butadienos/química , Fraccionamiento Químico , Glicósidos/química , Glicósidos/metabolismo , Hidrólisis , Poligalacturonasa/metabolismo , Terpenos/análisis , Terpenos/química
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