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1.
Lab Anim ; 54(1): 63-72, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31674858

RESUMO

Voluntary wheel running (VWR) behaviour is a sensitive indicator of disturbed wellbeing and used for the assessment of individual experimental severity levels in laboratory mice. However, monitoring individual VWR performance usually requires single housing, which itself might have a negative effect on wellbeing. In consideration of the 3Rs principle, VWR behaviour was evaluated under group-housing conditions. To test the applicability for severity assessment, this readout was evaluated in a dextran sodium sulphate (DSS) induced colitis model. For continuous monitoring, an automated system with integrated radio-frequency identification technology was used, enabling detection of individual VWR. After a 14-day adaptation period mice demonstrated a stable running performance. Analysis during DSS treatment in combination with repeated facial vein phlebotomy and faecal sampling procedure resulted in significantly reduced VWR behaviour during the course of colitis and increased VWR during disease recovery. Mice submitted to phlebotomy and faecal sampling but no DSS treatment showed less reduced VWR but a longer-lasting recovery. Application of a cluster model discriminating individual severity levels based on VWR and body weight data revealed the highest severity level in most of the DSS-treated mice on day 7, but a considerable number of control mice also showed elevated severity levels due to sampling procedures alone. In summary, VWR sensitively indicated the course of DSS colitis severity and the impact of sample collection. Therefore, monitoring of VWR is a suitable method for the detection of disturbed wellbeing due to DSS colitis and sampling procedure in group-housed female laboratory mice.


Assuntos
Colite/fisiopatologia , Sulfato de Dextrana/efeitos adversos , Atividade Motora , Animais , Colite/induzido quimicamente , Modelos Animais de Doenças , Feminino , Abrigo para Animais , Camundongos , Camundongos Endogâmicos C57BL , Estresse Psicológico
2.
Mult Scler Relat Disord ; 10: 63-65, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27919500

RESUMO

Thrombotic microangiopathy (TMA) is a rare but increasingly recognized complication of interferon-beta therapy, which can be associated with serious sequelae. We report on a 53-year-old woman with a longstanding history of relapsing-remitting multiple sclerosis, who developed TMA after 15 years of high-dose treatment with subcutaneous interferon-beta-1a. The patient presented with headaches, an epileptic seizure, confusion, and arterial hypertension. Laboratory findings included thrombocytopenia and hemolytic anemia. Despite of severe clinical manifestations and pronounced laboratory abnormalities, therapy with corticosteroids, plasma exchange and rituximab was associated with a favorable outcome and return to her premorbid level of functioning.


Assuntos
Corticosteroides/uso terapêutico , Fatores Imunológicos/uso terapêutico , Interferon beta/efeitos adversos , Troca Plasmática , Rituximab/uso terapêutico , Microangiopatias Trombóticas/terapia , Encéfalo/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Fatores Imunológicos/efeitos adversos , Interferon beta/uso terapêutico , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/complicações , Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Microangiopatias Trombóticas/diagnóstico por imagem , Microangiopatias Trombóticas/etiologia , Resultado do Tratamento
3.
Otol Neurotol ; 36(10): 1759-65, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26571409

RESUMO

OBJECTIVES: In recent years, cochlear implants have been applied successfully for the treatment of unilateral hearing loss with quite surprising benefit. One reason for this successful treatment, including the relief from tinnitus, could be the normalization of spontaneous activity in the central auditory pathway because of the electrical stimulation. The present study, therefore, investigated at a cellular level, the effect of a unilateral chronic intracochlear stimulation on key structures of the central auditory pathway. DESIGN: Normal-hearing guinea pigs were mechanically single-sided deafened through a standard HiFocus1j electrode array (on a HiRes 90k cochlear implant) being inserted into the first turn of the cochlea. Four to five electrode contacts could be used for the stimulation. Six weeks after surgery, the speech processor (Auria) was fitted, based on tNRI values and mounted on the animal's back. The two experimental groups were stimulated 16 hours per day for 90 days, using a HiRes strategy based on different stimulation rates (low rate (275 pps/ch), high rate (5000 pps/ch)). The results were compared with those of unilateral deafened controls (implanted but not stimulated), as well as between the treatment groups. All animals experienced a standardized free field auditory environment. RESULTS: The low-rate group showed a significantly lower average spontaneous activity bilaterally in the dorsal cochlear nucleus and the medial geniculate body than the controls. However, there was no difference in the inferior colliculus and the primary auditory cortex. Spontaneous activity of the high-rate group was also reduced bilaterally in the dorsal cochlear nucleus and in the primary auditory cortex. No differences could be observed between the high-rate group and the controls in the contra-lateral inferior colliculus and medial geniculate body. The high-rate group showed bilaterally a higher activity in the CN and the MGB compared with the low-rate group, whereas in the IC and in the AC a trend for an opposite effect could be determined. CONCLUSIONS: Unilateral intracochlear electrical stimulation seems to facilitate the homeostasis of the network activity, since it decreases the spontaneous activity that is usually elevated upon deafferentiation. The electrical stimulation per se seems to be responsible for the bilateral changes described above, rather than the particular nature of the electrical stimulation (e.g., rate). The normalization effects of electrical stimulation found in the present study are of particular importance in cochlear implant recipients with single-sided deafness.


Assuntos
Vias Auditivas/fisiopatologia , Implantes Cocleares , Surdez/fisiopatologia , Surdez/terapia , Lateralidade Funcional/fisiologia , Animais , Animais Recém-Nascidos , Córtex Auditivo/fisiopatologia , Cóclea/fisiopatologia , Implante Coclear , Núcleo Coclear/fisiopatologia , Modelos Animais de Doenças , Cobaias
4.
Clin Cancer Res ; 16(22): 5469-80, 2010 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21062934

RESUMO

PURPOSE: Atu027, a novel RNA interference therapeutic, has been shown to inhibit lymph node metastasis in orthotopic prostate cancer mouse models. The aim of this study is to elucidate the pharmacologic activity of Atu027 in inhibiting hematogenous metastasis to the target organ lung in four different preclinical mouse models. EXPERIMENTAL DESIGN: Atu027 compared with vehicle or control small interfering RNA lipoplexes was tested in two experimental lung metastasis models (Lewis lung carcinoma, B16V) and spontaneous metastasis mouse models (MDA-MB-435, MDA-MB-231, mammary fat pad). Different dosing schedules (repeated low volume tail vein injections) were applied to obtain insight into effective Atu027 treatment. Primary tumor growth and lung metastasis were measured, and tissues were analyzed by immunohistochemistry and histology. In vitro studies in human umbilical vein endothelial cells were carried out to provide an insight into molecular changes on depletion of PKN3, in support of efficacy results. RESULTS: Intravenous administration of Atu027 prevents pulmonary metastasis. In particular, formation of spontaneous lung metastasis was significantly inhibited in animals with large tumor grafts as well as in mice with resected primary mammary fat pad tumors. In addition, we provide evidence that an increase in VE-cadherin protein levels as a downstream result of PKN3 target gene inhibition may change endothelial function, resulting in reduced colonization and micrometastasis formation. CONCLUSION: Atu027 can be considered as a potent drug for preventing lung metastasis formation, which might be suitable for preventing hematogenous metastasis in addition to standard cancer therapy.


Assuntos
Carcinoma Pulmonar de Lewis/prevenção & controle , Carcinoma Pulmonar de Lewis/secundário , Modelos Animais de Doenças , Neoplasias Pulmonares/prevenção & controle , Neoplasias Pulmonares/secundário , Interferência de RNA , RNA Interferente Pequeno/uso terapêutico , Animais , Relação Dose-Resposta a Droga , Esquema de Medicação , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/enzimologia , Células Endoteliais/metabolismo , Humanos , Injeções Intravenosas , Camundongos , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Cancer Res ; 68(23): 9788-98, 2008 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-19047158

RESUMO

We have previously described a small interfering RNA (siRNA) delivery system (AtuPLEX) for RNA interference (RNAi) in the vasculature of mice. Here we report preclinical data for Atu027, a siRNA-lipoplex directed against protein kinase N3 (PKN3), currently under development for the treatment of advanced solid cancer. In vitro studies revealed that Atu027-mediated inhibition of PKN3 function in primary endothelial cells impaired tube formation on extracellular matrix and cell migration, but is not essential for proliferation. Systemic administration of Atu027 by repeated bolus injections or infusions in mice, rats, and nonhuman primates results in specific, RNAi-mediated silencing of PKN3 expression. We show the efficacy of Atu027 in orthotopic mouse models for prostate and pancreatic cancers with significant inhibition of tumor growth and lymph node metastasis formation. The tumor vasculature of Atu027-treated animals showed a specific reduction in lymph vessel density but no significant changes in microvascular density.


Assuntos
Neoplasias Pancreáticas/terapia , Neoplasias da Próstata/terapia , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/genética , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Animais , Processos de Crescimento Celular/fisiologia , Progressão da Doença , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/enzimologia , Células HeLa , Humanos , Lipossomos/administração & dosagem , Metástase Linfática , Macaca fascicularis , Masculino , Camundongos , Camundongos SCID , Neovascularização Patológica/enzimologia , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Neovascularização Patológica/terapia , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Interferência de RNA , Ratos , Transfecção/métodos
6.
J Anat ; 212(2): 164-79, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18179474

RESUMO

Two marsupial species (Monodelphis domestica, Macropus eugenii) and four eutherian species (Mesocricetus auratus, Suncus murinus, Tupaia belangeri and Cavia aperea) were examined to compare and contrast the timing of lung and metabolic development during the postnatal maturation of the mammalian respiratory apparatus. Using light, scanning and transmission electron microscopy, the lung structural changes were correlated with indirect calorimetry to track the metabolic development. Marsupial and eutherian species followed the same pattern of mammalian lung development, but differed in the developmental pace. In the two newborn marsupial species, the lung parenchyma was at the early terminal sac stage, with large terminal air sacs, and the lung developed slowly. In contrast, the newborn eutherian species had more advanced lungs at the late terminal sac stage in altricial species (M. auratus, S. murinus) and at the alveolar stage in precocial species (T. belangeri, C. aperea). Postnatal lung development proceeded rapidly in eutherian species. The marsupial species had a low metabolic rate at birth and achieved adult metabolism late in postnatal development. In contrast, newborn eutherian species had high metabolic rates and reached adult metabolism during the first week of life. The time course of the metabolic development is thus tightly linked to the structural differentiation of the lungs and the timing of postnatal lung development. These differences in the neonatal lung structure and the timing of postnatal lung maturation between marsupial and eutherian species reflect their differing reproductive strategies.


Assuntos
Animais Recém-Nascidos/anatomia & histologia , Pulmão/crescimento & desenvolvimento , Mamíferos/crescimento & desenvolvimento , Envelhecimento/fisiologia , Animais , Feminino , Pulmão/ultraestrutura , Masculino , Marsupiais/crescimento & desenvolvimento , Microscopia Eletrônica
7.
Artigo em Inglês | MEDLINE | ID: mdl-11897185

RESUMO

Oxygen consumption, heat production (HP) and core temperature (T(af)) were measured over 3 h in 20-34-day-old Muscovy duck and 12-21-day-old chicken embryos at ambient temperature (T(a)) of 37.5 degrees C and thereafter for 3 h at T(a) of 39.0 degrees C. At 37.5 degrees C T(a), HP increased with age in avian embryos of both species, following an exponential function. In muscovy duck embryos, a plateau phase occurred between D29 and D32; in chicken embryos, a similar plateau occurred between D19 and D21. T(af) rose in accordance with HP, and the relationships between T(af) and HP could be described by significant linear regressions in both species. Mostly, HP increased in embryos of both species during heat load, but by less than calculated by the van't Hoff rule; however, there was often also a decrease in HP under these conditions. Obviously, in avian embryos high T(a) causes a down-regulation of HP mediated by active thermoregulatory mechanisms. This is in agreement with data describing the influence of hyperthermia on HP in the postnatal period of birds and mammals. Because of this, the term 'second chemical thermoregulation' defined by Gelineo [C. R. Soc. Biol. (1936) 122 337] for birds and mammals should also be used for avian embryos.


Assuntos
Patos/embriologia , Embrião não Mamífero/metabolismo , Temperatura Alta , Animais , Embrião de Galinha , Consumo de Oxigênio , Especificidade da Espécie
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