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1.
Arch Ital Urol Androl ; 96(1): 12214, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38572722

RESUMO

INTRODUCTION AND OBJECTIVES: Artificial urinary sphincter (AUS) is a treatment option for women with stress urinary incontinence (SUI) after failure of previous surgery or as a primary procedure in severe intrinsic sphincter deficiency (ISD). The aim of the study was to assess the long-term efficacy and risk factors for surgical revision and definitive explantation of AUS laparoscopic implantation in female patients. METHODS: A retrospective review of all women submitted to AUS implantation between April 2005 and March 2023 was conducted. The AUS was implanted via transperitoneal laparoscopic approach, by two experienced surgeons. The primary endpoint was postoperative continence. Continence was defined as no leakage and no pad usage or leakage and/or pad usage with no impact on social life and failure as leakage and/or pad usage impacting social life. As secondary outcomes, clinical predictive factors for AUS revision and definitive explantation were evaluated. RESULTS: In the last 18 years, females with a mean age of 68±12 years-old were submitted to laparoscopic implantation of AUS. Early overall complication rate was 16%, but only one case was Clavien-Dindo ≥3. After a median follow-up of 67 months, 22.2% of the patients needed a device revision, the majority due to mechanical device dysfunction. AUS definitive explantation was performed in 16%, mainly due to urethral/vaginal erosion (9.9%) and infection (6.2%). Patients with age ≥70 years and follow-up ≥10 years significantly predisposed for device revision. At the time of the last follow-up, 72% of the patients were keeping the urinary continency. CONCLUSIONS: Laparoscopic AUS implantation in females is an effective treatment for SUI due to ISD. Meanwhile, adequate patient selection, multidisciplinary evaluation and careful expectation management are essential to achieving good results, concerning their significant complication rate.


Assuntos
Laparoscopia , Doenças Uretrais , Incontinência Urinária por Estresse , Esfíncter Urinário Artificial , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Esfíncter Urinário Artificial/efeitos adversos , Resultado do Tratamento , Incontinência Urinária por Estresse/cirurgia , Incontinência Urinária por Estresse/etiologia , Laparoscopia/efeitos adversos , Uretra/cirurgia , Doenças Uretrais/cirurgia , Implantação de Prótese/métodos , Estudos Retrospectivos
2.
J Synchrotron Radiat ; 31(Pt 1): 162-176, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37933848

RESUMO

The SIRIUS beamline of Synchrotron SOLEIL is dedicated to X-ray scattering and spectroscopy of surfaces and interfaces, covering the tender to mid-hard X-ray range (1.1-13 keV). The beamline has hosted a wide range of experiments in the field of soft interfaces and beyond, providing various grazing-incidence techniques such as diffraction and wide-angle scattering (GIXD/GIWAXS), small-angle scattering (GISAXS) and X-ray fluorescence in total reflection (TXRF). SIRIUS also offers specific sample environments tailored for in situ complementary experiments on solid and liquid surfaces. Recently, the beamline has added compound refractive lenses associated with a transfocator, allowing for the X-ray beam to be focused down to 10 µm × 10 µm while maintaining a reasonable flux on the sample. This new feature opens up new possibilities for faster GIXD measurements at the liquid-air interface and for measurements on samples with narrow geometries.

4.
Xenobiotica ; 53(5): 412-420, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37432873

RESUMO

Morpholine (MOR) has a broad spectrum of use and represents high risk of human exposure. Ingested MOR can undergo endogenous N-nitrosation in the presence of nitrosating agents forming N-nitrosomorpholine (NMOR), classified as possible human carcinogen by the International Agency for Research on Cancer.In this study, we evaluated the MOR toxicokinetics in six groups of male Sprague-Dawley rats orally exposed to 14C-radiolabelled MOR and NaNO2. The major urinary metabolite of MOR, N-nitrosohydroxyethylglycine (NHEG), was measured through HPLC as an index of endogenous N-nitrosation. Mass balance and toxicokinetic profile of MOR were determined by measuring radioactivity in blood/plasma and excreta.MOR reached maximum blood concentration 30 minutes after administration. Elimination rate was rapid (70% in 8h). Most of the radioactivity was excreted in the urine (80.9 ± 0.5%) and unchanged 14C-MOR was the main compound excreted in the urine (84% of the dose recovered). 5.8% of MOR is not absorbed and/or was not recovered.Endogenous nitrosation of MOR was demonstrated by the detection of NHEG. The maximum conversion rate found was 13.3 ± 1.2% and seems to be impacted by the MOR/NaNO2 ratio.These results help refining our knowledge of the endogenous production of NMOR, a possible human carcinogen.

5.
Cancers (Basel) ; 14(20)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36291815

RESUMO

Radiotherapy for localized prostate cancer has increased the cure and survival rates of patients. Besides its local tumoricidal effects, ionizing radiation has been linked to mechanisms leading to systemic immune activation, a phenomenon called the abscopal effect. In this study, we performed gene expression analysis on peripheral blood from prostate cancer patients obtained post- radiotherapy and showed that 6 genes, including CCR7, FCGR2B, BTLA, CD6, CD3D, and CD3E, were down-regulated by a range of 1.5-2.5-fold as compared to pre-radiotherapy samples. The expression of the signature consisting of these six genes was also significantly lower post- vs. pre-radiotherapy. These genes are involved in various tumor-promoting immune pathways and their down-regulation post-radiotherapy could be considered beneficial for patients. This is supported by the fact that low mRNA expression levels for the 6-gene signature in the prostate tumor tissue was linked to better survival. Importantly, we report that this 6-gene signature strongly correlated with a favorable prognosis regardless of poor standard clinicopathological parameters (i.e., Gleason score ≥ 8 and T3 (including T3a and T3b). Our pioneering data open the possibility that the 6-gene signature identified herein may have a predictive value, but this requires further long-term studies.

6.
Toxicol Pathol ; 50(1): 153-157, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34814786

RESUMO

Baclofen is a γ-aminobutyric acid-B receptor agonist used for control of spastic muscle activity and as a treatment for alcohol abuse. The review of the nonclinical database suggested a data gap for potential carcinogenicity following long-term use. Regulatory requirements for pharmaceutical safety testing of cancer-causing potential have historically included 2-year rodent studies in rats and mice. The availability of transgenic models with greater specificity and sensitivity to carcinogens provides safety testing alternatives that align with the 3Rs. The carcinogenicity of baclofen was evaluated in CB6F1-TgrasH2 transgenic mice following daily oral administration at 45, 90, and 180 mg/kg/d for 26 weeks, preceded by a 2-week drug-conditioning period. There were no treatment-related palpable masses or neoplastic findings, and survival rates were not affected by the baclofen treatment. In conclusion, baclofen was considered as noncarcinogenic in CB6F1-TgrasH2 mice, which is consistent with results previously obtained in a 2-year rat study.


Assuntos
Baclofeno , Carcinógenos , Animais , Baclofeno/toxicidade , Testes de Carcinogenicidade/métodos , Camundongos , Camundongos Transgênicos , Preparações Farmacêuticas , Ratos
7.
Cancers (Basel) ; 13(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208480

RESUMO

The herpes virus entry mediator (HVEM) delivers a negative signal to T cells mainly through the B and T lymphocyte attenuator (BTLA) molecule. Thus, HVEM/BTLA may represent a novel immune checkpoint during an anti-tumor immune response. However, a formal demonstration that HVEM can represent a target for cancer immunotherapy is still lacking. Here, we first showed that HVEM and BTLA mRNA expression levels were associated with a worse progression-free interval in patients with prostate adenocarcinomas, indicating a detrimental role for the HVEM/BTLA immune checkpoint during prostate cancer progression. We then showed that administration of a monoclonal antibody to human HVEM resulted in a twofold reduction in the growth of a prostate cancer cell line in NOD.SCID.gc-null mice reconstituted with human T cells. Using CRISPR/Cas9, we showed that the therapeutic effect of the mAb depended on HVEM expression by the tumor, with no effect on graft vs. host disease or activation of human T cells in the spleen. In contrast, the proliferation and number of tumor-infiltrating leukocytes increased following treatment, and depletion of CD8+ T cells partly alleviated treatment's efficacy. The expression of genes belonging to various T cell activation pathways was enriched in tumor-infiltrating leukocytes, whereas genes associated with immuno-suppressive pathways were decreased, possibly resulting in modifications of leukocyte adhesion and motility. Finally, we developed a simple in vivo assay in humanized mice to directly demonstrate that HVEM expressed by the tumor is an immune checkpoint for T cell-mediated tumor control. Our results show that targeting HVEM is a promising strategy for prostate cancer immunotherapy.

8.
Immunol Res ; 68(1): 7-12, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32144721

RESUMO

During World War I (WWI), infectious diseases including tetanus were among the most important causes of death. Even though its efficacy was somewhat controversial before the war, tetanus antiserum played a key role in reducing the mortality of this disease. A vial of tetanus antiserum dating back from WWI, left behind on the French battlefield by the US Army, was borrowed from a private collection and opened. The serum contained within was characterized by orthogonal biochemical techniques to determine if any neutralizing IgGs could remain after 100 years of storage. In vitro analysis by Size Exclusion Chromatography and Serum Protein Electrophoresis suggested the presence of residual IgG. In spite of our hopes, these IgGs were not able to protect mice against tetanus toxin challenge in a neutralizing assay. Even though our results indicate the presence of remaining IgGs inside the serum, they were functionally disabled. These results show that obscurity alone is insufficient to protect IgGs from degradation over very long periods of time at room temperature. HIGHLIGHTS: Tetanus antiserum found its place in the therapeutic arsenal during World War I A century-old vial of tetanus antiserum was opened for biochemical and in vivo characterization Biochemical assays revealed the presence of proteins having all the characteristics of IgGs The serum was unable to protect mice against toxinic challenge.


Assuntos
Clostridium tetani/imunologia , Soros Imunes/análise , Imunização Passiva/história , Imunoglobulina G/metabolismo , Tétano/imunologia , Animais , Eletroforese das Proteínas Sanguíneas , Cromatografia em Gel , História do Século XIX , História do Século XX , História do Século XXI , Humanos , Camundongos , Testes de Neutralização , Toxina Tetânica/imunologia , I Guerra Mundial
9.
Immunol. Res. ; 68: 7-12, 2020.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib17524

RESUMO

During World War I (WWI), infectious diseases including tetanus were among the most important causes of death. Even though its efficacy was somewhat controversial before the war, tetanus antiserum played a key role in reducing the mortality of this disease. A vial of tetanus antiserum dating back from WWI, left behind on the French battlefield by the US Army, was borrowed from a private collection and opened. The serum contained within was characterized by orthogonal biochemical techniques to determine if any neutralizing IgGs could remain after 100 years of storage. In vitro analysis by Size Exclusion Chromatography and Serum Protein Electrophoresis suggested the presence of residual IgG. In spite of our hopes, these IgGs were not able to protect mice against tetanus toxin challenge in a neutralizing assay. Even though our results indicate the presence of remaining IgGs inside the serum, they were functionally disabled. These results show that obscurity alone is insufficient to protect IgGs from degradation over very long periods of time at room temperature.

10.
Immunol Res, v. 68, p. 7-12, mar. 2020
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-2967

RESUMO

During World War I (WWI), infectious diseases including tetanus were among the most important causes of death. Even though its efficacy was somewhat controversial before the war, tetanus antiserum played a key role in reducing the mortality of this disease. A vial of tetanus antiserum dating back from WWI, left behind on the French battlefield by the US Army, was borrowed from a private collection and opened. The serum contained within was characterized by orthogonal biochemical techniques to determine if any neutralizing IgGs could remain after 100 years of storage. In vitro analysis by Size Exclusion Chromatography and Serum Protein Electrophoresis suggested the presence of residual IgG. In spite of our hopes, these IgGs were not able to protect mice against tetanus toxin challenge in a neutralizing assay. Even though our results indicate the presence of remaining IgGs inside the serum, they were functionally disabled. These results show that obscurity alone is insufficient to protect IgGs from degradation over very long periods of time at room temperature.

12.
Urology ; 114: e11-e15, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29378278

RESUMO

OBJECTIVE: To report the case of a 29-year-old patient presenting with renal splenosis along with a complete review of literature on this condition. Splenosis is a frequent condition following abdominal trauma or splenectomy, described as splenic tissue that autotransplants into a heterotopic location. However, renal splenosis is rare and often mistaken with renal carcinoma. MATERIALS AND METHODS: The patient was initially referred to our department for a renal mass incidentally discovered on ultrasound. Further investigation included with computed tomography and magnetic resonance imaging. RESULTS: Imaging features revealed a well circumscribed solid renal mass, exhibiting an isosignal on T1- and T2-weighted sequences in comparison with the renal cortex. The mass exhibited a heterogeneous enhancement on the arterial and portal phases, homogeneous patterns during the delayed phases, and high signal intensity on diffusion-weighted images. A partial nephrectomy was performed and pathological examination revealed the final diagnosis of renal splenosis. CONCLUSION: Imaging features alone do not provide a definitive diagnosis of splenosis but suggestive past history associated with imaging findings consistent with splenic tissue should lead to 99m technetium-sulfur colloid scanning or ferumoxid-enhanced MRI to avoid useless surgery.


Assuntos
Granuloma de Células Plasmáticas/diagnóstico por imagem , Neoplasias Renais/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Esplenose/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Diagnóstico Diferencial , Granuloma de Células Plasmáticas/cirurgia , Humanos , Neoplasias Renais/cirurgia , Masculino , Nefrectomia/métodos , Doenças Raras , Medição de Risco , Esplenose/cirurgia
13.
Urol Oncol ; 36(1): 11.e7-11.e12, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28993058

RESUMO

OBJECTIVE: To evaluate the pathological concordance rate of multiple synchronous renal masses (MSRM) presumed to be sporadic and to analyze predictive factors of concordance. MATERIAL AND METHODS: We identified from our institutional database patients with sporadic MSRM treated at our center between January 2000 and December 2015. All tumors were reviewed by a dedicated uropathologist. Pathological concordance rate was analyzed regarding clinical characteristics and preoperative imaging. RESULTS: We included 112 patients: 50 had unilateral synchronous renal masses and 62 bilateral synchronous renal masses. A total of 291 tumors were analyzed, with an average of 2.6 tumors per patient. Overall, the malignant concordance rate was 91.6%, the pathological concordance rate was 67.3% and the grade concordance rate was 62.5%. In univariate analysis, predictive factors of histological concordance were bilateral synchronous renal masses (odds ratio [OR] = 3.39; 95% CI: 1.06-10.8; P = 0.04), age<60 years (OR = 3.04; 95% CI: 1.2-7.7; P = 0.02) and ≥3 lesions (OR = 2.41; 95% CI: 1.03-5.68; P = 0.04). In multivariate analysis, age<60 remained significantly associated with histological concordance (OR = 3.84; 95% CI: 1.24-11.9; P = 0.02). CONCLUSIONS: The histological concordance rate of MSRM is low. Age at diagnosis <60 years, bilateral lesions and ≥3 tumors are predictive factors of histological concordance, but the pathological diagnosis remains difficult to predict. This heterogeneity is important to take into account, particularly when choosing the treatment upon the renal biopsy results from a single lesion.


Assuntos
Carcinoma de Células Renais/genética , Heterogeneidade Genética , Neoplasias Renais/genética , Neoplasias Renais/patologia , Carcinoma de Células Renais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Clin Cancer Res ; 21(13): 3031-40, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25688160

RESUMO

PURPOSE: Clear cell renal cell carcinoma (ccRCC) has shown durable responses to checkpoint blockade therapies. However, important gaps persist in the understanding of its immune microenvironment. This study aims to investigate the expression and prognostic significance of immune checkpoints in primary and metastatic ccRCC, in relation with mature dendritic cells (DC) and T-cell densities. EXPERIMENTAL DESIGN: We investigated the infiltration and the localization of CD8(+) T cells and mature DC, and the expression of immune checkpoints (PD-1, LAG-3, PD-L1, and PD-L2) in relation with prognosis, in 135 primary ccRCC tumors and 51 ccRCC lung metastases. RNA expression data for 496 primary ccRCC samples were used as confirmatory cohort. RESULTS: We identify two groups of tumors with extensive CD8(+) T-cell infiltrates. One group, characterized by high expression of immune checkpoints in the absence of fully functional mature DC, is associated with increased risk of disease progression. The second group, characterized by low expression of immune checkpoints and localization of mature DC in peritumoral immune aggregates (tertiary lymphoid structures), is associated with good prognosis. CONCLUSIONS: The expression of the immune checkpoints and the localization of DC in the tumor microenvironment modulate the clinical impact of CD8(+) T cells in ccRCC.


Assuntos
Carcinoma de Células Renais/imunologia , Neoplasias Renais/imunologia , Antígenos CD/metabolismo , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/fisiologia , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/secundário , Intervalo Livre de Doença , Humanos , Estimativa de Kaplan-Meier , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Linfócitos do Interstício Tumoral/fisiologia , Análise Multivariada , Prognóstico , Proteína 2 Ligante de Morte Celular Programada 1/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Modelos de Riscos Proporcionais , Microambiente Tumoral , Proteína do Gene 3 de Ativação de Linfócitos
15.
Food Chem Toxicol ; 50(3-4): 445-54, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22265941

RESUMO

Parabens (PB) are preservatives used in food, drugs and personal care products preventing microbial and fungal contamination. We investigated ADME profiles of [14C]-methyl-, propyl- or butylparaben (MP, PP, BP) following single oral, dermal or subcutaneous (BP) doses at 100 mg/kg to Sprague-Dawley rats. Plasma Cmax and AUC values after oral or subcutaneous doses were 4- to 10-fold higher relative to respective values after dermal administration. tmax ranged from 0.5, 2 or 8 h after oral, subcutaneous or dermal administration, respectively. MP produced higher blood Cmax and AUC levels relative to those after PP or BP. Following oral or subcutaneous administration, urinary excretion was predominant (>70%, mainly during the first 24 h), less than 4% were eliminated in the feces, 2% were retained in the tissues and carcasses. Following dermal application, >50% of the dose was unabsorbed, 14-27% or <2% were respectively excreted in the urine or feces, respectively. Overall, parabens were well absorbed after oral and subcutaneous, and partially absorbed after dermal administration. All administration routes produced a single peak in the plasma, corresponding to that of para-hydroxybenzoic acid (PHBA) suggesting that PB produce no significant systemic exposure of mammalian organisms after oral, topical or subcutaneous administration.


Assuntos
Parabenos/farmacocinética , Animais , Área Sob a Curva , Vias de Administração de Medicamentos , Feminino , Masculino , Parabenos/administração & dosagem , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
16.
J Neurochem ; 110(3): 976-89, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19493160

RESUMO

Transient exposure to ethanol (EtOH) results in a massive neurodegeneration in the developing brain leading to behavioral and cognitive deficits observed in fetal alcohol syndrome. There is now compelling evidence that K+ channels play an important role in the control of programmed cell death. The aim of the present work was to investigate the involvement of K+ channels in the EtOH-induced cerebellar granule cell death and/or survival. At low and high concentrations, EtOH evoked membrane depolarization and hyperpolarization, respectively. Bath perfusion of EtOH (10 mM) depressed the I(A) (transient K+ current) potassium current whereas EtOH (400 mM) provoked a marked potentiation of the specific I(K) (delayed rectifier K+ current) current. Pipette dialysis with GTPgammaS or GDPbetaS did not modify the effects of EtOH (400 mM) on both membrane potential and I(K) current. In contrast, the reversible depolarization and slowly recovering inhibition of I(A) induced by EtOH (10 mM) became irreversible in the presence of GTPgammaS. EtOH (400 mM) induced prodeath responses whereas EtOH (10 mM) and K+ channel blockers promoted cell survival. Altogether, these results indicate that in cerebellar granule cells, EtOH mediates a dual effect on K+ currents partly involved in the control of granule cell death.


Assuntos
Cerebelo/fisiologia , Etanol/administração & dosagem , Neurônios/fisiologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Cerebelo/citologia , Cerebelo/efeitos dos fármacos , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Neurônios/efeitos dos fármacos , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/fisiologia , Ratos , Ratos Wistar
17.
Neurobiol Dis ; 32(1): 66-80, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18652895

RESUMO

Cisplatin is a chemotherapeutic agent whose use is limited by side effects including neuropathies. In proliferating cells, toxic action of cisplatin is based on DNA interactions, while, in quiescent cells, it can induce apoptosis by interacting with proteins. In the present study, we compared cytotoxic mechanisms activated by cisplatin in primate and rodent neurons and in ovary cells in order to determine whether the anti-apoptotic peptide PACAP could selectively reduce neurotoxicity. In quiescent neurons, JNK and sphingomyelinase inhibitors blocked cisplatin-induced cell death. Toxicity was associated with DNA laddering, caspase-3 and -9 activations and Bax induction. These effects were prevented by PACAP. In proliferating cells, cisplatin activated caspase-8 but had no effect on caspase-9. PACAP exerted no protective effect. These data indicate that cisplatin activates distinct apoptotic pathways in quiescent neurons and proliferating cells and that PACAP may reduce neurotoxicity of cisplatin without affecting its chemotherapeutic efficacy.


Assuntos
Proteínas Reguladoras de Apoptose/fisiologia , Apoptose/fisiologia , Cisplatino/antagonistas & inibidores , Proteínas Mitocondriais/fisiologia , Neurônios/fisiologia , Ovário/citologia , Ovário/fisiologia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/fisiologia , Animais , Apoptose/efeitos dos fármacos , Células CHO , Callithrix , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Cisplatino/uso terapêutico , Cisplatino/toxicidade , Cricetinae , Cricetulus , Feminino , Macaca fascicularis , Masculino , Neurônios/citologia , Neurônios/efeitos dos fármacos , Técnicas de Cultura de Órgãos , Ovário/efeitos dos fármacos , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
18.
J Comp Neurol ; 504(4): 427-39, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17663433

RESUMO

The neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) exerts trophic activities during cerebellar development, and a neuroprotective effect of PACAP has been demonstrated in pathological conditions such as stroke. However, all these data have been obtained in rodents, and neuroprotective effects of PACAP in primates remain unknown. Because of their evolutionary relationships with humans, monkeys represent powerful models for validating the therapeutic interest in PACAP. The objective of the present study was to characterize PACAP and its receptors in the cerebellum of two nonhuman primates. RT-PCR and in situ hybridization experiments revealed that PACAP is expressed in the cerebellum by Purkinje cells. Via immunohistochemistry, PACAP was detected in Purkinje cells and radial glial fibers. With regard to PACAP receptors, PAC1-R and VPAC1-R were detected by RT-PCR. In situ hybridization revealed a strong expression of PAC1-R and VPAC1-R in the granule cell layer (GCL), and VPAC1-R was also expressed in the Purkinje cell layer. A high density of PACAP binding sites was visualized in the GCL and the Purkinje cell layer. Competition studies indicated that, in the GCL, PACAP induced complete displacement of [(125)I]PACAP27 binding, whereas vasoactive intestinal polypeptide (VIP) was a weak competitor. In contrast, in the Purkinje cell layer, both PACAP and VIP displaced [(125)I]PACAP27 binding. Measurement of cAMP levels showed that PACAP is a powerful activator of adenylyl cyclase, whereas VIP is about 100-fold less potent. Altogether, these observations constitute the first demonstration of a functional PACAPergic system in monkey cerebellum. They strongly suggest that neuroprotective effects of PACAP can be transposed to primates, including human.


Assuntos
Cerebelo/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Animais , Callithrix , Cerebelo/citologia , Feminino , Imuno-Histoquímica , Macaca fascicularis , Masculino , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/classificação
19.
Int J Toxicol ; 25(6): 499-521, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17132609

RESUMO

The laboratory toxicologist is frequently faced with the challenge of selecting appropriate vehicles or developing utilitarian formulations for use in in vivo nonclinical safety assessment studies. Although there are many vehicles available that may meet physical and chemical requirements for chemical or pharmaceutical formulation, there are wide differences in species and route of administration specific to tolerances to these vehicles. In current practice, these differences are largely approached on a basis of individual experience as there is only scattered literature on individual vehicles and no comprehensive treatment or information source. This approach leads to excessive animal use and unplanned delays in testing and development. To address this need, a consulting firm and three contract research organizations conducted a rigorous data mining operation of control (vehicle) data from studies dating from 1991 to present. The results identified 65 single component vehicles used in 368 studies across multiple species (dog, primate, rat, mouse, rabbit, guinea pig, minipig, chick embryo, and cat) by multiple routes. Reported here are the results of this effort, including maximum tolerated use levels by species, route, and duration of study, with accompanying dose limiting toxicity. Also included are basic chemical information and a review of available literature on each vehicle, as well as guidance on volume limits and pH by route and some basic guidance on nonclinical formulation development.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Veículos Farmacêuticos/toxicidade , Animais , Bases de Dados Factuais , Vias de Administração de Medicamentos , Veículos Farmacêuticos/administração & dosagem , Testes de Toxicidade
20.
J Neurochem ; 99(4): 1237-50, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17026529

RESUMO

The neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) inhibits C2-ceramide-induced cell death through blockade of the mitochondrial apoptotic pathway in rat cerebellar granule neurones. However, the gene induction processes and transcription factors involved in the anti-apoptotic effect of PACAP remain unknown. Here, we show that PACAP and C2-ceramide activate activator protein-1 (AP-1) DNA binding in a dose- and time-dependent manner, but generate different AP-1 dimers. Thus, PACAP increased the proportion of c-Fos and Jun D while C2-ceramide increased c-Jun and reduced c-Fos in AP-1 complexes. In addition, PACAP strongly activated c-Fos gene expression while C2-ceramide markedly increased c-Jun phosphorylation. The effect of PACAP on c-Fos expression was blocked by the mitogen-activated protein kinase/extracellular signal-regulated kinase (MEK) inhibitor, U0126, while phosphorylation of c-Jun induced by C2-ceramide was abrogated by the protein phosphatase 2A (PP2A) inhibitor, okadaic acid. Transfection of immature granule cells with c-Fos siRNA, which strongly reduced basal and PACAP-stimulated levels of the protein, totally prevented the stimulatory effect of PACAP on Bcl-2 expression. The present study demonstrates that AP-1 complexes containing c-Fos mediate the effect of PACAP on Bcl-2 gene expression in cerebellar granule neurones. Our data also indicate that different AP-1 dimers are associated with the pro-apoptotic effect of C2-ceramide and the anti-apoptotic effect of PACAP.


Assuntos
Sistema de Sinalização das MAP Quinases/fisiologia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Esfingosina/análogos & derivados , Fator de Transcrição AP-1/metabolismo , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Córtex Cerebelar/efeitos dos fármacos , Córtex Cerebelar/metabolismo , Proteínas de Ligação a DNA/efeitos dos fármacos , Proteínas de Ligação a DNA/metabolismo , Relação Dose-Resposta a Droga , Regulação para Baixo/genética , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fosfoproteínas Fosfatases/antagonistas & inibidores , Fosfoproteínas Fosfatases/metabolismo , Fosforilação/efeitos dos fármacos , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/farmacologia , Proteína Fosfatase 2 , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-jun/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-jun/metabolismo , Ratos , Ratos Wistar , Esfingosina/metabolismo , Esfingosina/farmacologia , Ativação Transcricional/efeitos dos fármacos , Ativação Transcricional/fisiologia
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