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1.
EJNMMI Res ; 12(1): 49, 2022 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-35962869

RESUMO

The experimental outcomes of small-animal positron emission tomography (PET) imaging with 18F-labelled fluorodeoxyglucose (18F-FDG) can be particularly compromised by animal preparation and care. Several works intend to improve research reporting and amplify the quality and reliability of published research. Though these works provide valuable information to plan and conduct animal studies, manuscripts describe different methodologies-standardization does not exist. Consequently, the variation in details reported can explain the difference in the experimental results found in the literature. Additionally, the resources and guidelines defining protocols for small-animal imaging are scarce, making it difficult for researchers to obtain and compare accurate and reproducible data. Considering the selection of suitable procedures key to ensure animal welfare and research improvement, this paper aims to prepare the way for a future guideline on mice preparation and care for PET imaging with 18F-FDG. For this purpose, a global standard protocol was created based on recommendations and good practices described in relevant literature.

2.
Neurol Sci ; 42(5): 1963-1967, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32995988

RESUMO

Huntington's disease (HD) is a neurodegenerative disorder caused by a CAG nucleotide expansion, which encodes the amino acid glutamine, in the huntingtin gene. HD is characterized by motor, cognitive, and psychiatric dysfunctions. In a previous study, we showed by qPCR that some genes altered in an HD mouse model were also altered in blood of HD patients. These alterations were mainly with respect to the dynein family. Therefore, this study aimed to investigate whether dynein light chain Tctex type 1 (DYNLT1) is altered in HD patients and if there is a correlation between DYNLT1 gene expression changes and disease progression. We assessed the DYNLT1 gene expression in the blood of 19 HD patients and 20 healthy age-matched controls. Also, in 6 of these patients, we analyzed the DYNLT1 expression at two time points, 3 years apart. The DYNLT1 gene expression in the whole blood of HD patients was significantly downregulated and this difference was widened in later stages. These data suggest that DYNLT1 could emerge as a peripheral prognostic indicator in HD and, also, might be a target for potential intervention in the future.


Assuntos
Dineínas/genética , Doença de Huntington , Animais , Estudos de Casos e Controles , Modelos Animais de Doenças , Progressão da Doença , Dineínas/sangue , Expressão Gênica , Humanos , Proteína Huntingtina/genética , Doença de Huntington/genética , Camundongos
3.
Lupus ; 26(5): 490-496, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28394236

RESUMO

Opportunistic infections can cause manifestations that resemble neuropsychiatric systemic lupus erythematosus and they can also trigger lupus flares. Therefore, central nervous system infections as differential diagnosis in neuropsychiatric systemic lupus erythematosus may be difficult, leading to delayed diagnosis and specific treatment. Central nervous system infection in systemic lupus erythematosus is not common but, if left misdiagnosed and not treated promptly, can be fatal. Complementary diagnosis tests are generally non-specific and disappointing. Caution with immunosuppressive drug treatment should be emphasized while an opportunistic infection cannot be ruled out. In this review, we discuss the various types of central nervous system infections reported in systemic lupus erythematosus patients, highlighting the importance of their early recognition in order to improve morbidity and mortality. Prevention with vaccination is a recommended approach.


Assuntos
Doenças do Sistema Nervoso Central/microbiologia , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Vasculite Associada ao Lúpus do Sistema Nervoso Central/diagnóstico , Infecções Oportunistas/diagnóstico , Diagnóstico Diferencial , Diagnóstico Precoce , Feminino , Humanos , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Lúpus Eritematoso Sistêmico/complicações , Masculino , Infecções Oportunistas/complicações , Exacerbação dos Sintomas
4.
Lupus ; 25(11): 1254-9, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26923283

RESUMO

OBJECTIVE: To evaluate the immunogenicity of the 23-valent pneumococcal polysaccharide vaccine (PPSV23) in adult systemic lupus erythematosus patients undergoing (IS group) and not undergoing (non-IS group) immunosuppressive treatment. METHODS: In this prospective open-label study from February 2013 to April 2014, 54 patients had blood samples collected immediately before PPSV23 immunization and 4-6 weeks thereafter for the ELISA measurement of IgG antibody levels against seven pneumococcal serotypes. Positive vaccine response for each serotype was defined as a four-fold or greater antibody response over baseline levels or as a post-vaccine anti-pneumococcal IgG level ≥1.3 µg/ml when baseline values were <1.3 µg/ml. Patients should have responded appropriately to ≥70% of the tested serotypes. We also calculated the mean ratio of post- to pre-vaccination anti-pneumococcal IgG levels. RESULTS: Twenty-eight patients were classified into the IS group and 26 into non-IS group. The median dose of prednisone at baseline was ≤5 mg/day in both groups. Serotype-specific vaccine response rates were not significantly different between the groups. Less than 40% of patients responded adequately by both vaccine response criteria, being numerically lower among IS patients. The mean ratio of increase in anti-pneumococcal levels was 6.4 versus 4.7 (p = 0.001) in non-IS and IS groups, respectively. CONCLUSION: The vaccine was poorly immunogenic, especially among adult systemic lupus erythematosus patients under immunosuppressive therapy.


Assuntos
Imunossupressores/uso terapêutico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/imunologia , Vacinas Pneumocócicas/imunologia , Adulto , Feminino , Humanos , Imunogenicidade da Vacina , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sorogrupo
5.
Neurobiol Dis ; 73: 163-73, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25160573

RESUMO

Huntington's disease (HD) is an autosomal-dominant neurodegenerative disorder caused by a polyglutamine expansion in the amino-terminal region of the huntingtin protein (htt), leading to motor dysfunction, cognitive decline, psychiatric alterations, and death. The metabotropic glutamate receptor 5 (mGluR5) has been implicated in HD and we have recently demonstrated that mGluR5 positive allosteric modulators (PAMs) are neuroprotective in vitro. In the present study we demonstrate that the mGluR5 PAM, CDPPB, is a potent neuroprotective drug, in vitro and in vivo, capable of delaying HD-related symptoms. The HD mouse model, BACHD, exhibits many HD features, including neuronal cell loss, htt aggregates, motor incoordination and memory impairment. However, chronic treatment of BACHD mice with CDPPB 1.5 mg/kg s.c. for 18 weeks increased the activation of cell signaling pathways important for neuronal survival, including increased AKT and ERK1/2 phosphorylation and augmented the BDNF mRNA expression. CDPPB chronic treatment was also able to prevent the neuronal cell loss that takes place in the striatum of BACHD mice and decrease htt aggregate formation. Moreover, CDPPB chronic treatment was efficient to partially ameliorate motor incoordination and to rescue the memory deficit exhibited by BACHD mice. Importantly, no toxic effects or stereotypical behavior were observed upon CDPPB chronic treatment. Thus, CDPPB is a potential drug to treat HD, preventing neuronal cell loss and htt aggregate formation and delaying HD symptoms.


Assuntos
Benzamidas/uso terapêutico , Doença de Huntington/tratamento farmacológico , Doença de Huntington/patologia , Doença de Huntington/fisiopatologia , Neurônios/efeitos dos fármacos , Pirazóis/uso terapêutico , Fatores Etários , Animais , Morte Celular/efeitos dos fármacos , Células Cultivadas , Corpo Estriado/citologia , Modelos Animais de Doenças , Embrião de Mamíferos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Ácido Glutâmico/farmacologia , Humanos , Proteína Huntingtina , Doença de Huntington/genética , Camundongos , Camundongos Transgênicos , Mitocôndrias/patologia , Atividade Motora/efeitos dos fármacos , Atividade Motora/genética , Proteínas do Tecido Nervoso/metabolismo , Neurônios/patologia , Reconhecimento Psicológico/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Sinapses/patologia , Sinapses/ultraestrutura
6.
Immunol Res ; 61(1-2): 160-3, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25412733

RESUMO

Systemic lupus erythematous (SLE) is an autoimmune disease that presents an increased susceptibility to infections which may trigger reactivation. Disease flares have been mostly associated with parvovirus B19, cytomegalovirus, EBV and Mycobacterium tuberculosis infections, but it is probable that many other agents may also induce innate and adaptive immune system stimulation including the production of autoantibodies as ANA, anti nDNA and anti-ß2-GPI mainly in lepromatous leprosy. Mycobacterium leprae not only may determine symptoms that mimic lupus flares, including autoantibodies production, but could also act as a trigger for lupus reactivation; however, its association is still not fully explored. As demonstrated for tuberculosis, it is quite possible that molecular mimicry may also be involved in the interface of these two diseases. Some studies reported shared epitopes among idiotypes derived from 8E7 and TH9 lepromatous antibodies and those obtained from SLE patients, and it could partially explain the triggering phenomenon of SLE caused by M. leprae. We report and discuss three Brazilian patients whose disease was inactive and presented disease flares concurrently with the diagnosis of leprosy.


Assuntos
Hanseníase/complicações , Lúpus Eritematoso Sistêmico/complicações , Adulto , Biópsia , Feminino , Humanos , Imunossupressores/uso terapêutico , Hanseníase/diagnóstico , Hanseníase/tratamento farmacológico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Masculino , Resultado do Tratamento
7.
Br J Pharmacol ; 169(4): 909-21, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23489026

RESUMO

BACKGROUND AND PURPOSE: Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder caused by a polyglutamine expansion in the huntingtin protein. We have previously demonstrated that the cell signalling of the metabotropic glutamate receptor 5 (mGluR5) is altered in a mouse model of HD. Although mGluR5-dependent protective pathways are more activated in HD neurons, intracellular Ca²âº release is also more pronounced, which could contribute to excitotoxicity. In the present study, we aim to investigate whether mGluR5 positive allosteric modulators (PAMs) could activate protective pathways without triggering high levels of Ca²âº release and be neuroprotective in HD. EXPERIMENTAL APPROACH: We performed a neuronal cell death assay to determine which drugs are neuroprotective, Western blot and Ca²âº release experiments to investigate the molecular mechanisms involved in this neuroprotection, and object recognition task to determine whether the tested drugs could ameliorate HD memory deficit. KEY RESULTS: We find that mGluR5 PAMs can protect striatal neurons from the excitotoxic neuronal cell death promoted by elevated concentrations of glutamate and NMDA. mGluR5 PAMs are capable of activating Akt without triggering increased intracellular Ca²âº concentration ([Ca²âº]i ); and Akt blockage leads to loss of PAM-mediated neuroprotection. Importantly, PAMs' potential as drugs that may be used to treat neurodegenerative diseases is highlighted by the neuroprotection exerted by mGluR5 PAMs on striatal neurons from a mouse model of HD, BACHD. Moreover, mGluR5 PAMs can activate neuroprotective pathways more robustly in BACHD mice and ameliorate HD memory deficit. CONCLUSIONS AND IMPLICATIONS: mGluR5 PAMs are potential drugs that may be used to treat neurodegenerative diseases, especially HD.


Assuntos
Doença de Huntington/tratamento farmacológico , Transtornos da Memória/prevenção & controle , Proteínas do Tecido Nervoso/agonistas , Fármacos Neuroprotetores/uso terapêutico , Nootrópicos/uso terapêutico , Receptor de Glutamato Metabotrópico 5/agonistas , Regulação Alostérica/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Células Cultivadas , Corpo Estriado/citologia , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Embrião de Mamíferos/citologia , Ativação Enzimática/efeitos dos fármacos , Proteína Huntingtina , Doença de Huntington/metabolismo , Doença de Huntington/fisiopatologia , Transtornos da Memória/etiologia , Camundongos , Camundongos Endogâmicos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fármacos Neuroprotetores/efeitos adversos , Fármacos Neuroprotetores/farmacologia , Nootrópicos/efeitos adversos , Nootrópicos/farmacologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fosforilação/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/agonistas , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor de Glutamato Metabotrópico 5/metabolismo
8.
Lupus ; 21(5): 570-4, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22129601

RESUMO

OBJECTIVE: To determine the epidemiological profile and outcome of patients with lupus nephritis (LN) undergoing renal transplantation. METHODS: The archival records of 50 patients with LN and end-stage renal disease (ESRD) treated by kidney transplantation from March 1992 to December 2010 were reviewed. All patients met the American College of Rheumatology criteria for systemic lupus erythematosus (SLE). RESULTS: Fourteen patients were included in the study. The majority were women (85.7%) and non-Caucasian (85.7%); the mean age at diagnosis of SLE and LN was 24 ± 8 and 25 ± 8 years, respectively. Renal biopsy was performed in 12 patients, with 75% of them showing proliferative lesions (class III and IV according to the World Health Organization and International Society of Nephrology/Renal Pathology Society classification). Thirteen patients (93%) underwent intermittent hemodialysis or peritoneal dialysis before transplantation. The median time between the start of dialysis and transplantation was 30 months (range 3-103 months); 67% of the procedures involved deceased donors and 33% involved living-related donors. The graft survival rates were 93.3%, 90.9%, and 85.7% at 1, 5 and 10 years, respectively. Post-transplant immunosuppressive agents were mycophenolate mofetil (84%), azathioprine (17%), tacrolimus (25%), sirolimus (58%) and cyclosporine (8%). Eight episodes of acute rejection were noted in six patients. There was a graft loss due to renal vein thrombosis in the one patient with secondary antiphospholipid syndrome. The mean SLICC by the time of kidney transplantation was 5 ± 2. In total, 13 patients (92.8%) developed at least one infectious event during the follow-up, with one dying in the immediate post-transplant period because of sepsis. Two patients (14%) had a lupus flare. There was no clinical or histological evidence of LN recurrence. CONCLUSION: LN is the major cause of morbidity in SLE, with progression to ESRD in 10-22% of cases. Despite concerns about LN recurrence after renal transplantation, the data obtained in our sample indicate this procedure as a safe alternative therapy for ESRD in this population.


Assuntos
Falência Renal Crônica/cirurgia , Transplante de Rim/métodos , Nefrite Lúpica/cirurgia , Adulto , Brasil/epidemiologia , Progressão da Doença , Feminino , Seguimentos , Rejeição de Enxerto/epidemiologia , Sobrevivência de Enxerto , Humanos , Imunossupressores/uso terapêutico , Falência Renal Crônica/etiologia , Nefrite Lúpica/complicações , Nefrite Lúpica/epidemiologia , Masculino , Diálise Peritoneal/métodos , Recidiva , Diálise Renal/métodos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
9.
Lupus ; 19(13): 1485-91, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20605875

RESUMO

Human papillomavirus (HPV) is the etiological agent of cervical cancer, the second most prevalent neoplasia among women. Although it has been proven that systemic lupus erythematosus (SLE) patients have higher frequency of cervical dysplasia, few studies have focused on HPV prevalence among them. This study aimed to investigate HPV prevalence among SLE patients and to evaluate associated risk factors, including the use of immunosuppressors (IM). Total DNA extracted from cervical samples of 173 SLE patients and 217 women (control group) submitted to routine cervical cytopathology was used as template in polymerase chain reaction (PCR)-based assays for detection of HPV DNA. HPV genotyping was performed by type-specific PCR, PCR-RFLP and/or DNA sequencing. Statistical methods included univariate analysis and logistic regression. Despite presenting significantly fewer HPV risk factors, SLE patients were found to have a threefold increase in HPV infection, mostly genotypes 53, 58, 45, 66, 6, 84, 83, 61, as compared with controls, who presented types 6, 18 and 61 more frequently. The higher rate of HPV infection was associated with immunosuppressive therapy. This study provides evidence that SLE patients have a high prevalence of HPV infection, which is even higher with the use of IM, a condition that might necessitate a more frequent cervical cancer screening program for these women.


Assuntos
Imunossupressores/efeitos adversos , Lúpus Eritematoso Sistêmico/complicações , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/etiologia , Adolescente , Adulto , Idoso , Sequência de Bases , Estudos de Casos e Controles , Estudos Transversais , DNA Viral/análise , Feminino , Genótipo , Humanos , Imunossupressores/uso terapêutico , Modelos Logísticos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/epidemiologia , Pessoa de Meia-Idade , Papillomaviridae/genética , Infecções por Papillomavirus/epidemiologia , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , Prevalência , Estudos Prospectivos , Fatores de Risco , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/virologia , Esfregaço Vaginal , Adulto Jovem
10.
Neuroscience ; 167(3): 765-73, 2010 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-20167259

RESUMO

Cholinergic neurons rely on the sodium-dependent choline transporter CHT to provide choline for synthesis of acetylcholine. CHT cycles between cell surface and subcellular organelles, but little is known about regulation of this trafficking. We hypothesized that activation of protein kinase C with phorbol ester modulates choline uptake by altering the rate of CHT internalization from or delivery to the plasma membrane. Using SH-SY5Y cells that stably express rat CHT, we found that exposure of cells to phorbol ester for 2 or 5 min significantly increased choline uptake, whereas longer treatment had no effect. Kinetic analysis revealed that 5 min phorbol ester treatment significantly enhanced V(max) of choline uptake, but had no effect on K(m) for solute binding. Cell-surface biotinylation assays showed that plasma membrane levels of CHT protein were enhanced following 5 min phorbol ester treatment; this was blocked by protein kinase C inhibitor bisindolylmaleimide-I. Moreover, CHT internalization was decreased and delivery of CHT to plasma membrane was increased by phorbol ester. Our results suggest that treatment of neural cells with the protein kinase C activator phorbol ester rapidly and transiently increases cell surface CHT levels and this corresponds with enhanced choline uptake activity which may play an important role in replenishing acetylcholine stores following its release by depolarization.


Assuntos
Encéfalo/metabolismo , Proteínas do Tecido Nervoso/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Proteínas da Membrana Plasmática de Transporte de Neurotransmissores/efeitos dos fármacos , Proteína Quinase C/efeitos dos fármacos , Acetato de Tetradecanoilforbol/análogos & derivados , Acetilcolina/biossíntese , Animais , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Endocitose/efeitos dos fármacos , Endocitose/fisiologia , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Inibidores Enzimáticos/farmacologia , Cinética , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , Proteínas da Membrana Plasmática de Transporte de Neurotransmissores/metabolismo , Proteína Quinase C/metabolismo , Transporte Proteico/efeitos dos fármacos , Transporte Proteico/fisiologia , Ratos , Acetato de Tetradecanoilforbol/farmacologia
11.
Clin Rev Allergy Immunol ; 38(2-3): 163-8, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19548122

RESUMO

Systemic lupus erythematosus (SLE) is an autoimmune disease that frequently requires treatment with high doses of corticosteroids and immunosuppressive drugs. Primary defects in the innate immunity also contribute to an increased susceptibility to infections. Patients with SLE are at an increased risk for infections with several pathogens, among them Mycobacterium tuberculosis, which is a significant cause of morbidity and mortality, especially in endemic regions. TB infection requires awareness for several reasons: first, TB infection thrives under conditions of immunosuppression, may it be secondary to the disease itself or its treatment. Second, shared antigens by mycobacteria and autoantigens have been described, which may be targets for autoantibodies. We present four Brazilian patients, in whom a diagnosis of tuberculosis was determined during or following persistent flares of their disease. The association of SLE and TB is discussed, as well as different aspects of the tuberculosis infection in this selected population, and its possible role in the course of SLE.


Assuntos
Lúpus Eritematoso Sistêmico/complicações , Tuberculose/complicações , Adulto , Antituberculosos/uso terapêutico , Feminino , Humanos , Imunossupressores/uso terapêutico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/fisiopatologia , Pessoa de Meia-Idade , Tuberculose/tratamento farmacológico , Tuberculose/fisiopatologia
12.
Cell Mol Biol (Noisy-le-grand) ; 55 Suppl: OL1138-50, 2009 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-19656467

RESUMO

It has been suggested that overexpression of neuronal Ca2+ sensor-1 (NCS-1) protein is implicated in the pathophysiology of neurodisorders such as schizophrenia, bipolar disturbance and X-linked mental retardation. The mechanism by which NCS-1 would be involved in the causes and/or consequences of these neurodisorders is still far from elucidation. Independent evidence has pointed NCS-1 as a key regulator of synaptic efficacy by altering the expression and activity of voltage-gated channels, inhibiting internalization of dopaminergic receptors, and altering phosphoinositide metabolism. In this study, we examined the possible participation of NCS-1 protein in signal transmission dependent on muscarinic receptor activation, using PC12 cells stably expressing NCS-1 (PC12-NCS-1). Carbachol (CCH; 300 microM) was able to evoke glutamate release more efficiently from PC12-NCS-1 (15.3+/-1.0nmol/mg of protein) than wild type cells (PC12-wt; 8.3+/-0.9nmol/mg of protein). This increase of glutamate release induced by CCH was independent on extracellular Ca2+ influx. Additionally, a larger increase of cytoplasmic levels of InsP3 (663.0+/-63.0 and 310.0+/-39.0% of fluorescence in A.U.) and [Ca2+]i (766.4+/-40.0 and 687.8+/-37.1nmol/L) was observed after CCH stimulus of PC12-NCS-1 compared with PC12-wt. Clearly distinction between intracellular Ca2+ dynamics was also observed in PC12-NCS-1 and PC12-wt. A larger increase followed by fast decay of [Ca2+]i was observed in PC12-NCS-1. A plateau with a delayed decay of [Ca2+]i was characteristic of PC12-wt [Ca2+]i response. Both enhancement of InsP3 production and glutamate release observed in PC12-NCS-1 were blocked by atropine (10 microM). Together, our data show that overexpression of NCS-1 in PC12 cells induces an enhancement of intracellular second messenger and transmitter release dependent on CCH response, suggesting that muscarinic signaling is "up-regulated" in this cell model.


Assuntos
Ácido Glutâmico/metabolismo , Proteínas Sensoras de Cálcio Neuronal/fisiologia , Neuropeptídeos/fisiologia , Receptores Muscarínicos/metabolismo , Transdução de Sinais/fisiologia , Animais , Cálcio/metabolismo , Cálcio/farmacologia , Carbacol/farmacologia , Quelantes/farmacologia , Agonistas Colinérgicos/farmacologia , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Microscopia de Fluorescência , Proteínas Sensoras de Cálcio Neuronal/genética , Proteínas Sensoras de Cálcio Neuronal/metabolismo , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Células PC12 , Transporte Proteico/efeitos dos fármacos , Ratos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Transfecção
13.
Pharmacogenomics J ; 7(3): 190-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16953235

RESUMO

Formyl-Met-Leu-Phe (fMLP) is a potent chemoattractant molecule released from both bacteria and damaged mitochondria that activates fMLP receptors (FPR) leading to neutrophil chemotaxis, degranulation and superoxide production. A common missense single nucleotide polymorphism in the human FPR1 gene at nucleotide c.32C>T results in the amino-acid substitution, p.I11T, in the FPR1 extracellular amino-terminus. The minor (c.32T) allele frequencies were 0.25, 0.27, 0.25, 0.15 and 0.14 in healthy Caucasian, African, East Indian, Chinese and Native Canadian individuals, respectively. In subjects homozygous for the p.T11 allele, we find elevated serum concentrations of C-reactive protein, increased absolute counts of blood leukocytes and neutrophils, and erythrocyte sedimentation rates. When expressed in HEK 293 and RBL-2H3 cells a substantial proportion of FPR1 p.I11T variant is retained intracellularly and agonist-independent internalization of the FPR1 p.I11T variant, but not the wild-type FPR1, is constitutively associated with beta-arrestin2-GFP in vesicles. Moreover, basal N-acetyl-D-glucosaminidase release is increased in primary neutrophils isolated from subjects either heterozygous or homozygous for the FPR1 p.T11 allele. Taken together, the data suggest an increased receptor activity and phenotypic expression of increased inflammatory indices in subjects with the p.T11 allele.


Assuntos
Arrestinas/fisiologia , Proteína C-Reativa/análise , Inflamação/etiologia , Mutação de Sentido Incorreto , Receptores de Formil Peptídeo/genética , Degranulação Celular , Linhagem Celular , Citoesqueleto/metabolismo , Humanos , Neutrófilos/fisiologia , Polimorfismo de Nucleotídeo Único , beta-Arrestinas
14.
J Neurochem ; 87(1): 136-46, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12969261

RESUMO

Synthesis of acetylcholine depends on the plasma membrane uptake of choline by a high affinity choline transporter (CHT1). Choline uptake is regulated by nerve impulses and trafficking of an intracellular pool of CHT1 to the plasma membrane may be important for this regulation. We have generated a hemagglutinin (HA) epitope tagged CHT1 to investigate the organelles involved with intracellular trafficking of this protein. Expression of CHT1-HA in HEK 293 cells establishes Na+-dependent, hemicholinium-3 sensitive high-affinity choline transport activity. Confocal microscopy reveals that CHT1-HA is found predominantly in intracellular organelles in three different cell lines. Importantly, CHT1-HA seems to be continuously cycling between the plasma membrane and endocytic organelles via a constitutive clathrin-mediated endocytic pathway. In a neuronal cell line, CHT1-HA colocalizes with the early endocytic marker green fluorescent protein (GFP)-Rab 5 and with two markers of synaptic-like vesicles, VAMP-myc and GFP-VAChT, suggesting that in cultured cells CHT1 is present mainly in organelles of endocytic origin. Subcellular fractionation and immunoisolation of organelles from rat brain indicate that CHT1 is present in synaptic vesicles. We propose that intracellular CHT1 can be recruited during stimulation to increase choline uptake in nerve terminals.


Assuntos
Clatrina/metabolismo , Endocitose/fisiologia , Endossomos/metabolismo , Hemicolínio 3/farmacologia , Proteínas de Membrana Transportadoras/metabolismo , Vesículas Sinápticas/metabolismo , Proteínas de Transporte Vesicular , Animais , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular , Humanos , Rim/citologia , Rim/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas de Membrana Transportadoras/efeitos dos fármacos , Proteínas de Membrana Transportadoras/genética , Camundongos , Neurônios/citologia , Neurônios/metabolismo , Proteínas R-SNARE , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Sinaptossomos/metabolismo , Proteínas Vesiculares de Transporte de Acetilcolina
15.
Int J Clin Pharmacol Ther ; 40(9): 424-30, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12358160

RESUMO

OBJECTIVES: To assess the bioequivalence of 2 formulations of carbamazepine and to develop and validate limited sampling strategy (LSS) models for estimating the area under the plasma concentration-time curve (AUC0-infinity) and the peak plasma concentration (Cmax) of carbamazepine. METHODS: Twenty-four (12 men, 12 women) healthy volunteers received single oral doses (400 mg) of carbamazepine, as reference and test conventional-release formulations, in a standard 2-sequence, 2-period crossover design. Bioequivalence assessment was based on the individual ratios of log-transformed values of AUC0-infinity and Cmax LSS modeling was developed in a training set of 12 randomly assigned volunteers and was validated on the other 12 subjects (validation set). RESULTS: Carbamazepine AUC0-infinity and Cmax can be accurately predicted (R2 = 0.89 - 0.95, precision = 2.6 - 7.2%) by single-point (72 h) and 2-point LSS models (6, 32 h), respectively. Bioequivalence assessments based on LSS-derived AUC0-infinity and Cmax provided results similar to those obtained using all the concentration-in-plasma data points, and indicated that the 2 formulations are bioequivalent. CONCLUSION: One-and 2-point LSS models provided accurate estimates of carbamazepine's AUC0-infinity and Cmax, and allowed correct assessment of bioequivalence between the formulations studied.


Assuntos
Anticonvulsivantes/farmacocinética , Carbamazepina/farmacocinética , Adulto , Anticonvulsivantes/sangue , Área Sob a Curva , Carbamazepina/sangue , Cromatografia Líquida de Alta Pressão , Feminino , Meia-Vida , Humanos , Masculino , Taxa de Depuração Metabólica , Equivalência Terapêutica
16.
Braz. j. med. biol. res ; 34(11): 1475-1485, Nov. 2001. ilus, tab
Artigo em Inglês | LILACS | ID: lil-303318

RESUMO

Bioanalytical data from a bioequivalence study were used to develop limited-sampling strategy (LSS) models for estimating the area under the plasma concentration versus time curve (AUC) and the peak plasma concentration (Cmax) of 4-methylaminoantipyrine (MAA), an active metabolite of dipyrone. Twelve healthy adult male volunteers received single 600 mg oral doses of dipyrone in two formulations at a 7-day interval in a randomized, crossover protocol. Plasma concentrations of MAA (N = 336), measured by HPLC, were used to develop LSS models. Linear regression analysis and a "jack-knife" validation procedure revealed that the AUC0- and the Cmax of MAA can be accurately predicted (R²>0.95, bias <1.5 percent, precision between 3.1 and 8.3 percent) by LSS models based on two sampling times. Validation tests indicate that the most informative 2-point LSS models developed for one formulation provide good estimates (R²>0.85) of the AUC (0-infinity) or Cmax for the other formulation. LSS models based on three sampling points (1.5, 4 and 24 h), but using different coefficients for AUC(0-infinity) and Cmax, predicted the individual values of both parameters for the enrolled volunteers (R²>0.88, bias = -0.65 and -0.37 percent, precision = 4.3 and 7.4 percent) as well as for plasma concentration data sets generated by simulation (R²>0.88, bias = -1.9 and 8.5 percent, precision = 5.2 and 8.7 percent). Bioequivalence assessment of the dipyrone formulations based on the 90 percent confidence interval of log-transformed AUC(0-infinity) and Cmax provided similar results when either the best-estimated or the LSS-derived metrics were used


Assuntos
Humanos , Masculino , Adulto , Dipirona , Área Sob a Curva , Intervalos de Confiança , Estudos Transversais , Dipirona
17.
Antimicrob Agents Chemother ; 45(11): 3029-36, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11600352

RESUMO

Amoxicillin plasma concentrations (n = 1,152) obtained from 48 healthy subjects in two bioequivalence studies were used to develop limited-sampling strategy (LSS) models for estimating the area under the concentration-time curve (AUC), the maximum concentration of drug in plasma (C(max)), and the time interval of concentration above MIC susceptibility breakpoints in plasma (T>MIC). Each subject received 500-mg amoxicillin, as reference and test capsules or suspensions, and plasma concentrations were measured by a validated microbiological assay. Linear regression analysis and a "jack-knife" procedure revealed that three-point LSS models accurately estimated (R(2), 0.92; precision, <5.8%) the AUC from 0 h to infinity (AUC(0-infinity)) of amoxicillin for the four formulations tested. Validation tests indicated that a three-point LSS model (1, 2, and 5 h) developed for the reference capsule formulation predicts the following accurately (R(2), 0.94 to 0.99): (i) the individual AUC(0-infinity) for the test capsule formulation in the same subjects, (ii) the individual AUC(0-infinity) for both reference and test suspensions in 24 other subjects, and (iii) the average AUC(0-infinity) following single oral doses (250 to 1,000 mg) of various amoxicillin formulations in 11 previously published studies. A linear regression equation was derived, using the same sampling time points of the LSS model for the AUC(0-infinity), but using different coefficients and intercept, for estimating C(max). Bioequivalence assessments based on LSS-derived AUC(0-infinity)'s and C(max)'s provided results similar to those obtained using the original values for these parameters. Finally, two-point LSS models (R(2) = 0.86 to 0.95) were developed for T>MICs of 0.25 or 2.0 microg/ml, which are representative of microorganisms susceptible and resistant to amoxicillin.


Assuntos
Amoxicilina/farmacocinética , Penicilinas/farmacocinética , Adulto , Área Sob a Curva , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Micrococcus luteus/efeitos dos fármacos , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Equivalência Terapêutica
18.
Braz J Med Biol Res ; 34(11): 1475-85, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11668360

RESUMO

Bioanalytical data from a bioequivalence study were used to develop limited-sampling strategy (LSS) models for estimating the area under the plasma concentration versus time curve (AUC) and the peak plasma concentration (Cmax) of 4-methylaminoantipyrine (MAA), an active metabolite of dipyrone. Twelve healthy adult male volunteers received single 600 mg oral doses of dipyrone in two formulations at a 7-day interval in a randomized, crossover protocol. Plasma concentrations of MAA (N = 336), measured by HPLC, were used to develop LSS models. Linear regression analysis and a "jack-knife" validation procedure revealed that the AUC(0-infinity) and the Cmax of MAA can be accurately predicted (R2>0.95, bias <1.5%, precision between 3.1 and 8.3%) by LSS models based on two sampling times. Validation tests indicate that the most informative 2-point LSS models developed for one formulation provide good estimates (R2>0.85) of the AUC(0-infinity) or Cmax for the other formulation. LSS models based on three sampling points (1.5, 4 and 24 h), but using different coefficients for AUC(0-infinity) and Cmax, predicted the individual values of both parameters for the enrolled volunteers (R2>0.88, bias = -0.65 and -0.37%, precision = 4.3 and 7.4%) as well as for plasma concentration data sets generated by simulation (R2>0.88, bias = -1.9 and 8.5%, precision = 5.2 and 8.7%). Bioequivalence assessment of the dipyrone formulations based on the 90% confidence interval of log-transformed AUC(0-infinity) and Cmax provided similar results when either the best-estimated or the LSS-derived metrics were used.


Assuntos
Dipirona/análogos & derivados , Dipirona/farmacocinética , Pirazolonas , Adulto , Área Sob a Curva , Intervalos de Confiança , Estudos Cross-Over , Dipirona/sangue , Humanos , Masculino , Equivalência Terapêutica
19.
Ren Fail ; 19(3): 475-9, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9154664

RESUMO

Hemolytic uremic syndrome (HUS) is a rare condition which most frequently follows gastrointestinal or respiratory infection episodes in young children, but it can also occur in other settings such as the postpartum period and during use of drugs such as oral contraconceptives, immunosuppressors, and antineoplastics. In early pregnancy, however, its frequency is thought to be very low. The authors report a case of a 30-year-old woman who developed HUS early in her first pregnancy. She had persistent aqueous diarrhea from the beginning of the pregnancy. At the 21st week she developed hypertension which in 2 weeks was followed by seizures, oliguria, and acute pulmonary edema despite intensive medical efforts to control her blood pressure. Surgical intervention for fetal delivery was performed. The patient was initially kept on continuous hemodialysis (CVVHD) followed by an alternate-day conventional hemodialysis schedule. A peripheral blood analysis showed a microangiopathic hemolytic anemia with thrombocytopenia; blood coagulation tests were completely normal. A brain CT scan and an abdominal MRI showed no major abnormalities. HUS was confirmed by a percutaneal kidney biopsy, performed at the 21st day of anuria. Techniques for identification of verotoxin-producing E. coli were not available. Renal function did not recover and the patient has been undergoing regular maintenance hemodialysis for a year.


Assuntos
Síndrome Hemolítico-Urêmica/diagnóstico , Complicações na Gravidez/diagnóstico , Adulto , Feminino , Síndrome Hemolítico-Urêmica/terapia , Humanos , Gravidez , Complicações na Gravidez/terapia , Complicações Hematológicas na Gravidez/diagnóstico , Complicações Hematológicas na Gravidez/terapia , Diálise Renal
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