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1.
Regul Toxicol Pharmacol ; 88: 125-137, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28624430

RESUMEN

With the emergence of novel biotherapeutic formats and immunostimulatory biotherapeutics in cancer immunotherapy, an understanding of immune-complex (IC) mediated hypersensitivity reactions in toxicology studies - and their differentiation from pharmacology - remains key to the preclinical evaluation of these drugs. In this review we provide an in-depth evaluation and comparison of case examples where IC-mediated hypersensitivity reactions were observed in cynomolgus monkeys. We provide details of the parameters evaluated in each study to substantiate and guide the interpretation of these findings. Five study cases (1 therapeutic protein, 4 monoclonal antibodies) are discussed for which effects ranged from minor to fatal. Common characteristics are the high incidence of clinical signs, detectable antidrug antibodies, and accelerated drug clearance up to virtual loss of exposure. In our experience, measurement of cytokine levels in vivo and detection of complement (split products) were supportive markers in situations where coagulopathy was suspected to play a role in the observed effects. Recommendations are outlined to prepare for root-cause analysis of suspected hypersensitivity reactions. Overall, a thorough analysis of the findings has helped to start clinical trials despite major findings. The hypersensitivity reactions with our human(ized) immunoglobulins have not proven to be predictive for humans.


Asunto(s)
Complejo Antígeno-Anticuerpo/inmunología , Terapia Biológica/efectos adversos , Hipersensibilidad/inmunología , Inmunoglobulina G/inmunología , Inmunoterapia/efectos adversos , Animales , Anticuerpos Monoclonales/inmunología , Citocinas/sangre , Humanos , Inmunoglobulina G/administración & dosificación , Macaca fascicularis
2.
Toxicol Appl Pharmacol ; 279(3): 419-427, 2014 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-24997324

RESUMEN

The incidence of micronucleated-cells is considered to be a marker of a genotoxic event and can be caused by direct- or indirect-DNA reactive mechanisms. In particular, small increases in the incidence of micronuclei, which are not associated with toxicity in the target tissue or any structurally altering properties of the compound, trigger the suspicion that an indirect mechanism could be at play. In a bone marrow micronucleus test of a synthetic peptide (a dual agonist of the GLP-1 and GIP receptors) that had been integrated into a regulatory 13-week repeat-dose toxicity study in the rat, small increases in the incidence of micronuclei had been observed, together with pronounced reductions in food intake and body weight gain. Because it is well established that folate plays a crucial role in maintaining genomic integrity and pronounced reductions in food intake and body weight gain were observed, folate levels were determined from plasma samples initially collected for toxicokinetic analytics. A dose-dependent decrease in plasma folate levels was evident after 4 weeks of treatment at the mid and high dose levels, persisted until the end of the treatment duration of 13-weeks and returned to baseline levels during the recovery period of 4 weeks. Based on these properties, and the fact that the compound tested (peptide) per se is not expected to reach the nucleus and cause DNA damage, the rationale is supported that the elevated incidence of micronucleated polychromatic erythrocytes is directly linked to the exaggerated pharmacology of the compound resulting in a decreased folate level.


Asunto(s)
Deficiencia de Ácido Fólico/inducido químicamente , Pruebas de Mutagenicidad/métodos , Mutágenos , Péptidos/toxicidad , Animales , Temperatura Corporal/efectos de los fármacos , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/ultraestructura , Línea Celular Tumoral , Aberraciones Cromosómicas/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Eritropoyesis/efectos de los fármacos , Deficiencia de Ácido Fólico/genética , Humanos , Linfocitos/efectos de los fármacos , Linfocitos/ultraestructura , Desnutrición/inducido químicamente , Ratones , Ratones Noqueados , Pruebas de Micronúcleos , Ratas , Receptores de la Hormona Gastrointestinal/metabolismo , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genética
3.
West J Nurs Res ; 34(6): 766-94, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22566289

RESUMEN

Homicide causes negative unintended consequences for family survivors. Family survivors face complicated grief and overwhelming loss with minimal support from others. The authors offered a retreat intervention as a way to ameliorate the effects of the homicidal death for family survivors of homicide. An exploratory longitudinal pilot study examined the feasibility and acceptability of the intervention and explored the impact of the TOZI© Healing intervention on participants' distress symptoms. Eight family members participated in the 2-day retreat and completed surveys at five time intervals over 30 months. Descriptive statistics and correlations were used to analyze the data. Although sample sizes were too small to achieve statistical significance, changes on selected holistic health outcomes, supported by overwhelmingly positive focus group responses to the intervention, affirm the need for further study.


Asunto(s)
Familia/psicología , Homicidio , Servicios de Salud Mental/organización & administración , Sobrevivientes , Humanos , Proyectos Piloto , Estrés Psicológico
4.
J Consult Clin Psychol ; 77(5): 855-66, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19803566

RESUMEN

Research has shown that mindfulness-based treatment interventions may be effective for a range of mental and physical health disorders in adult populations, but little is known about the effectiveness of such interventions for treating adolescent conditions. The present randomized clinical trial was designed to assess the effect of the mindfulness-based stress reduction (MBSR) program for adolescents age 14 to 18 years with heterogeneous diagnoses in an outpatient psychiatric facility (intent-to-treat N = 102). Relative to treatment-as-usual control participants, those receiving MBSR self-reported reduced symptoms of anxiety, depression, and somatic distress, and increased self-esteem and sleep quality. Of clinical significance, the MBSR group showed a higher percentage of diagnostic improvement over the 5-month study period and significant increases in global assessment of functioning scores relative to controls, as rated by condition-naïve clinicians. These results were found in both completer and intent-to-treat samples. The findings provide evidence that MBSR may be a beneficial adjunct to outpatient mental health treatment for adolescents.


Asunto(s)
Trastornos de Ansiedad/terapia , Atención , Actitud , Concienciación , Intención , Trastornos del Humor/terapia , Terapia por Relajación/psicología , Adolescente , Atención Ambulatoria , Trastornos de Ansiedad/psicología , Comorbilidad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Trastornos del Humor/psicología , Inventario de Personalidad , Terapia por Relajación/métodos , Resultado del Tratamiento
5.
Am J Clin Oncol ; 25(4): 325-36, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12151958

RESUMEN

The MX1 xenotransplant growing in nude mice was used as a model for estrogen- and progesterone-receptor-negative breast cancer. The effects of different therapeutic regimens-combinations of hyperthermia, chemotherapy, and irradiation-on the expression of proteins playing a role in tumor vascularization and apoptosis were investigated. Additionally, MX-1 tumors were exposed to hypoxia to investigate changes in protein expression related to angiogenesis. This is of particular importance with respect to antiangiogenic therapies that may be combined with the treatments mentioned before. Endothelial and adhesion factors, extracellular matrix (ECM) factors, apoptosis-regulating factors, and neuronal factors were examined by immunohistochemical techniques. Concerning vascularization, the most prominent changes were seen in the expression of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF), which increased strongly after hypoxia. The other cytokines, adhesion and ECM molecules, were either little affected or unaffected by the therapy. At the ultrastructural level, the walls of the tumor vessels are of the sinusoidal type, possessing many fenestrations. With regard to the second focus of this investigation, apoptosis, tumor cells again exerted the strongest differences after hypoxia where c-myc was clearly enhanced, whereas the effects on p53, bcl-2, and CD95 were extremely weak or not detectable. Furthermore, the neurotransmitter somatostatin, a possible "external" regulator of apoptosis, did not show treatment-related changes. In summary, it was shown that 1) within the group of apoptosis-regulating proteins c-myc was particularly affected by hypoxia, indicating a possible role for an activation-induced pathway of apoptosis in this context; 2) minor changes seen after treatment combined with hyperthermia point to a more acute vascular reaction (=dilatation), causing an increase of tissue pO2 rather than angiogenesis; and 3) the concentrations of the angiogenic factors VEGF and bFGF rose strongly under hypoxia, thereby possibly exerting counterproductive effects to antiangiogenic therapy but not to thermochemotherapy or irradiation. This supports the concept of a combined antiangiogenic, hyperthermia, chemo- and irradiation therapy.


Asunto(s)
Antineoplásicos Alquilantes/farmacología , Apoptosis/fisiología , Neoplasias de la Mama , Hipertermia Inducida , Hipoxia , Neovascularización Patológica , Animales , Neoplasias de la Mama/irrigación sanguínea , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Neoplasias de la Mama/radioterapia , Moléculas de Adhesión Celular/metabolismo , Terapia Combinada , Citocinas/metabolismo , Factores de Crecimiento Endotelial/metabolismo , Endotelinas/metabolismo , Proteínas de la Matriz Extracelular/metabolismo , Factor VIII/metabolismo , Femenino , Ifosfamida/farmacología , Inmunohistoquímica , Linfocinas/metabolismo , Ratones , Ratones Desnudos , Factor de Crecimiento Nervioso/metabolismo , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular , Ensayos Antitumor por Modelo de Xenoinjerto
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