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1.
Clin Exp Dermatol ; 47(4): 700-708, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34762763

RESUMO

BACKGROUND: Calciphylaxis is a life-threatening cutaneous ulcerative/necrotic disease characterized by vascular calcification/occlusion. It occurs most commonly in end-stage kidney disease (ESKD), known as uraemic calciphylaxis (UC) but can also occur in patients with chronic kidney disease (CKD) and normal kidney function (nonuraemic calciphylaxis; NUC). There are few large series of NUC in the literature. AIM: To compare the clinicopathological features of UC and NUC. METHODS: We retrospectively compared the clinicopathological features of 35 patients with NUC during the period 2010-2020 with those of 53 patients with UC (control group). Cases were classified as NUC in the absence of all of the following: ESKD, significant CKD (defined as serum creatinine > 3 mg/dL or creatinine clearance < 15 mL/min) and acute kidney injury requiring kidney replacement therapy or kidney transplantation. RESULTS: NUC represented 40% of the total cases, and there was a higher number of women (P < 0.01) and a higher median body mass index (P = 0.06) compared with the control UC group. Elevated parathyroid hormone was present in 44% of patients with NUC. Most of the tested patients were positive for lupus anticoagulants (56%). NUC biopsies showed a higher rate of extravascular calcium deposits (73% vs. 47%, P = 0.03). Dermal reactive vascular proliferation was the most common dermal change (32%). CONCLUSIONS: NUC is more common than previously reported and shows a higher predilection for obese postmenopausal women. Undiagnosed hyperparathyroidism shows a possible association with NUC. Lupus anticoagulants were positive in most patients. NUC biopsies are more likely than UC biopsies to display extravascular calcium deposition.


Assuntos
Calciofilaxia , Falência Renal Crônica , Insuficiência Renal Crônica , Calciofilaxia/diagnóstico , Feminino , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Insuficiência Renal Crônica/complicações , Estudos Retrospectivos , Fatores de Risco
2.
J Eur Acad Dermatol Venereol ; 36(10): 1774-1783, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35460287

RESUMO

BACKGROUND: Limited data are available on long-term efficacy and safety of biologics in patients with psoriasis and metabolic syndrome (MetS), a common comorbidity. OBJECTIVES: This analysis updates tildrakizumab efficacy and safety for up to 5 years in patients with and without MetS. METHODS: This was a post hoc analysis of the double-blind, randomized, placebo-controlled, phase 3 reSURFACE 1 (NCT01722331) and reSURFACE 2 (NCT01729754) trials in adult patients with moderate to severe chronic plaque psoriasis. Analyses included data through Week 244 from patients who continuously received tildrakizumab 100 (TIL100) or 200 mg (TIL200) and entered the extension studies, stratified by baseline MetS status. Efficacy was assessed via Psoriasis Area and Severity Index (PASI) scores. Safety was evaluated from exposure-adjusted incidence rates (EAIRs) of treatment-emergent adverse events (TEAEs). RESULTS: reSURFACE 1 and reSURFACE 2 analyses included 26 and 44 TIL100-treated patients with MetS, 98 and 167 TIL100-treated patients without MetS, 34 and 30 TIL200-treated patients with MetS, and 111 and 130 TIL200-treated patients without MetS, respectively. There were no clinically relevant differences in PASI 75/90/100 response rates at Week 244 between patients with vs without MetS. The proportion of patients with vs without MetS achieving absolute PASI score <3 at Week 244 was 53.8% vs 69.4% and 77.3% vs 80.8% in reSURFACE 1 and 2, respectively, for TIL100-treated patients and 58.8% vs 72.1% and 63.3% vs 72.3%, respectively, for TIL200-treated patients. In both studies, median reduction from baseline PASI score at all time points in patients with vs without MetS was >83% vs >89% for TIL100 and >85% vs >90% for TIL200. Pooled EAIRs of TEAEs, serious TEAEs, and TEAEs of special interest were similar in patients with and without MetS. CONCLUSIONS: Tildrakizumab maintains efficacy and a favorable safety profile over 5 years in patients with psoriasis regardless of MetS status.


Assuntos
Anticorpos Monoclonais Humanizados , Síndrome Metabólica , Psoríase , Adulto , Anticorpos Monoclonais Humanizados/efeitos adversos , Método Duplo-Cego , Humanos , Síndrome Metabólica/complicações , Síndrome Metabólica/tratamento farmacológico , Psoríase/complicações , Psoríase/tratamento farmacológico , Resultado do Tratamento
3.
Clin Exp Dermatol ; 43(8): 906-912, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29856076

RESUMO

BACKGROUND: Cutaneous dermatomyositis (DM) is often refractory to multiple systemic medications, suggesting a need for effective alternative treatments. AIM: To investigate the effects of intravenous immunoglobulin (IVIG) on patients with refractory cutaneous DM. METHODS: This was a retrospective review of 42 patients treated with IVIG for refractory cutaneous DM at our institution with clinical data available at DM diagnosis. IVIG was initiated for refractory cutaneous DM alone (n = 15) or refractory cutaneous and muscle/lung disease (n = 27) in patients with various DM subtypes. RESULTS: Overall, 83% of patients had cutaneous DM improvement, including 87% treated for refractory skin disease alone and 81% treated for refractory skin/muscle/lung disease. Cutaneous DM improvement occurred regardless of DM subtype, and was observed after a mean of 1.82 ± 1.38 IVIG cycles. No statistically significant clinical predictors of IVIG response or lack of response were detected. IVIG use resulted in decreased systemic glucocorticoid exposure with or without a decrease in steroid-sparing immunosuppressive medications in 80% of patients. This study is limited by its retrospective nature and lack of objective cutaneous DM activity assessment. CONCLUSION: Use of IVIG resulted in improvement of refractory cutaneous DM in the vast majority of patients relatively soon after initiation and regardless of DM subtype or clinical manifestations. Additionally, IVIG allowed decrease or discontinuation of immunosuppressive medications in 80% of patients. These findings suggest that IVIG can be a clinically efficacious and cost-effective treatment for refractory cutaneous DM and warrants prospective study.


Assuntos
Dermatomiosite/tratamento farmacológico , Imunoglobulinas Intravenosas/uso terapêutico , Fatores Imunológicos/uso terapêutico , Adulto , Resistência a Medicamentos , Feminino , Glucocorticoides/uso terapêutico , Humanos , Imunoglobulinas Intravenosas/efeitos adversos , Fatores Imunológicos/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
4.
Br J Dermatol ; 174(1): 158-64, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26490490

RESUMO

BACKGROUND: Clinically amyopathic dermatomyositis (CADM) is a subset of dermatomyositis (DM) characterized by the typical DM cutaneous manifestations but without myositis. There is a relative paucity of characterized cases of CADM in the peer-reviewed medical literature. OBJECTIVES: To characterize the clinical features, response to medications and malignancy-associated risk factors of patients with CADM with available baseline data seen at a single tertiary-care centre. METHODS: A retrospective review was undertaken of 44 patients with CADM with available clinical and serological data prior to onset of treatment. RESULTS: Patients with CADM comprised 18% of all patients with DM with baseline data available at our institution. Although the majority of patients showed improvement with the first prescribed treatment, most required additional medications to control their CADM. Six of 44 patients had an associated malignancy. Photosensitivity and periungual erythema were found to be associated with absence of malignancy (P = 0·03 and P = 0·02, respectively). Patients with malignancy-associated CADM were found to be more likely to have a cutaneous response with the first prescribed treatment than patients without malignancy (P = 0·04). CONCLUSIONS: CADM represents a significant subset of the DM population. As with classic DM, the cutaneous manifestations of CADM often represent a therapeutic challenge. A subset of patients with CADM has underlying malignancies, and these may differ from those typically associated with classic DM. Differences in serological abnormalities, cutaneous manifestations and response to first treatment among patients with CADM with and without malignancy were found, and suggest distinct pathophysiologies among CADM subsets. Characterization of this cohort expands the knowledge about this unique DM subset.


Assuntos
Dermatomiosite/tratamento farmacológico , Neoplasias/complicações , Idoso , Anticorpos Antinucleares/metabolismo , Fármacos Dermatológicos/administração & dosagem , Dermatomiosite/complicações , Exantema/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Esteroides/administração & dosagem
5.
Clin Exp Dermatol ; 41(4): 413-6, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26800651

RESUMO

The anti-CD20 peripheral B-cell depleting monoclonal antibody, rituximab, has been shown to be a safe and effective treatment for refractory pemphigus vulgaris (PV), a potentially fatal autoimmune blistering disease. We report a patient who developed skin nodules and arthralgias following successful treatment of refractory PV with rituximab. Clinical, serological and histological findings were consistent with a diagnosis of sarcoidosis. The nodules promptly responded to treatment with corticosteroids, and resolved without recurrence when the medication was tapered several months later. The temporal onset of sarcoidosis following treatment with rituximab and the eventual resolution, coupled with the remarkable similarities between the B-cell immunological environment expected in our patient during the post-rituximab period and the immunological environment described in patients with idiopathic sarcoidosis, strongly implicates exposure to rituximab as the trigger for sarcoidosis development in our patient. We propose that rituximab-induced sarcoidal granulomas may be a rare adverse effect of treatment with this medication, providing further support for an important role of B cells in the pathogenesis of sarcoidosis. With better understanding of the circumstances surrounding sarcoidosis development following rituximab administration, this medication could potentially be used to induce sarcoidosis in animal research models to study the immunopathogenesis of this disease.


Assuntos
Rituximab/efeitos adversos , Sarcoidose/induzido quimicamente , Sarcoidose/fisiopatologia , Corticosteroides/uso terapêutico , Fator Ativador de Células B/fisiologia , Linfócitos B/fisiologia , Biópsia , Feminino , Granuloma de Células Gigantes/patologia , Humanos , Pessoa de Meia-Idade , Pênfigo/tratamento farmacológico , Rituximab/uso terapêutico , Sarcoidose/diagnóstico , Sarcoidose/tratamento farmacológico
8.
Br J Dermatol ; 172(2): 428-36, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25142556

RESUMO

BACKGROUND: Smoking is a well-established risk factor for developing psoriasis and is associated with development of more severe disease. Smoking cessation does not appear to result in clinical improvement of psoriasis. Whether smoking in patients with psoriasis impacts response to systemic therapy is unknown. OBJECTIVES: To determine whether smokers with psoriasis with or without psoriatic arthritis respond to systemic agents as well as nonsmokers do. METHODS: We performed a retrospective review of patients with moderate-to-severe psoriasis with or without psoriatic arthritis seen at our institution, who were either active smokers or nonsmokers, and calculated changes in Physician's Global Assessment (PGA) scores after 3-16 months of systemic treatment. We also calculated the average number of systemic treatments tried per patient. RESULTS: Sixty-six patients (46 nonsmokers, 20 smokers) met our inclusion criteria. Changes in PGA scores between baseline and 3-16 months after initiation of systemic treatment did not significantly differ between smokers and nonsmokers, nor did the average number of systemic treatments tried per patient. We detected a borderline significant trend in the percentage of patients who had significant outcomes after treatment, with a higher percentage of patients smoking < 10 cigarettes daily achieving target PGA scores compared with those smoking > 10 cigarettes daily. Limitations of our study include its retrospective nature and the relatively small number of patients meeting our inclusion criteria. CONCLUSIONS: In our retrospectively studied cohort, smoking did not affect response to systemic treatment in patients with psoriasis. A prospective study examining the complex relationship between smoking, psoriasis and response to systemic therapy is warranted to explore this association better.


Assuntos
Fármacos Dermatológicos/uso terapêutico , Psoríase/tratamento farmacológico , Fumar/efeitos adversos , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
11.
Br J Dermatol ; 180(5): 974, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31025735
13.
Clin Epidemiol Glob Health ; 12: 100868, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34549098

RESUMO

INTRODUCTION: The outbreak of coronavirus posits deleterious consequences on global healthcare system while affecting human life in every aspect. Despite several measures undertaken to limit the socio-economic effect of coronavirus, various challenges remain pervasive, and one such challenge is mental health, particularly depression and anxiety. Therefore, this study examines the prevalence and determinants of depression and anxiety in Malaysian population during third wave of COVID-19. METHODS: A cross-sectional online survey was carried out via social media platforms and 1544 Malaysians were selected. The level of depression was assessed by Patient Health Questionnaires (PHQ-9) and scored accordingly for categorization. Zung's Self-Rating Anxiety Scale (SAS) was used as a self-assessment survey to quantify the level of anxiety of persons experiencing anxiety-related symptoms. Percentage distribution and logistic regression analysis were used in the data analysis. RESULTS: Results showed that one-fourth (25.1%) of the participants had severe depressive symptoms. Almost one-sixth (18.7%) had mild depressive symptoms and one-third (34.1%) had mild to moderate anxiety symptoms. Age, gender, and friends infected with virus were the three important predictors of depression and anxiety. The odds of having depression (OR = 1.44; C·I. = 1.32-1.62) and anxiety (OR = 1.36; C·I. = 1.27-1.47) were significantly higher among females than in males. CONCLUSION: A significant proportion of the study participants were facing mild to severe depression and anxiety symptoms which is very alarming as the pandemic is still now increasing across the country. Immediate interventions including community counselling programmes, TV and social media campaigns are urgently needed to reduce the psychological stress among the Malaysian population.

14.
Neuroscience ; 158(4): 1390-6, 2009 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-19135137

RESUMO

Stroke is the second most common cause of death and major cause of disability worldwide. Actual treatment involves surgery and/or thrombolytic drugs, but there is an urgent need for new approaches. Periodic acceleration, a rocking headward to footward movement of the whole body, is a non-invasive method to induce pulsatile shear stress on the vascular endothelium eliciting an enhanced production and secretion of endothelium-derived products such as nitric oxide, prostacyclin, prostaglandin E2, tissue plasminogen activator (tPA), and adrenomedullin. All these products have been shown to protect the brain from ischemic injuries. A rat model of focal brain ischemia was treated with application of periodic acceleration for 3 h immediately after the onset of ischemia. Controls remained static for the same period of time. Brain damage was assessed by magnetic resonance imaging (MRI) and biochemical markers. A significant reduction in brain damage was observed, 7 days post-ischemia, in rocked rats when compared with the static controls, through MRI. Furthermore, rocked animals had significantly lower levels of Beclin 1 and fractin than their static counterparts, and some isoforms of nitric oxide synthase were regulated by periodic acceleration. Our results show that periodic acceleration may provide a novel, affordable, non-invasive therapeutic option for the treatment of stroke.


Assuntos
Aceleração , Lesões Encefálicas/etiologia , Lesões Encefálicas/terapia , Isquemia Encefálica/complicações , Terapia por Exercício/métodos , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Proteína Beclina-1 , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Isquemia Encefálica/induzido quimicamente , Isquemia Encefálica/etiologia , Caspase 3/genética , Caspase 3/metabolismo , Modelos Animais de Doenças , Endotelina-1 , Regulação da Expressão Gênica/fisiologia , Imageamento por Ressonância Magnética/métodos , Masculino , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Periodicidade , Ratos , Ratos Wistar , Fatores de Tempo
15.
Neuroscience ; 142(3): 799-808, 2006 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-16952423

RESUMO

Exposure to hypobaric hypoxia produces neuropsychological disorders. The brain nitrergic system was investigated following hypobaric hypoxia in the presence or absence of nitric oxide synthase (NOS) inhibitors. Adult rats were exposed to a simulated altitude of 8325 m (27,000 ft) for 7 h and killed after 0, 1, 3, 5, and 10 days of recovery. In addition to normobaric controls, three experimental groups were studied: i) subjected to hypobaric hypoxia without inhibitors; ii) subjected to hypobaric hypoxia and treated with 7-nitroindazole; iii) subjected to hypobaric hypoxia and treated with N(omega)-nitro-l-arginine methyl ester (l-NAME). Cerebral cortex was assayed by immunohistochemistry, Western blotting, and enzymatic assays. In animals subjected to hypobaric hypoxia without inhibitors, there was an increase in neuronal nitric oxide synthase (nNOS) immunoreactivity and Ca(2+)-dependent NOS activity from 0 to 1 days of reoxygenation. In these animals, inducible nitric oxide synthase (iNOS) expression and Ca(2+)-independent activity were undetectable, but nitrotyrosine immunoreactivity was found in some neurons. Administration of either inhibitor prevented the increase in nNOS immunoreactivity and enzymatic activity provoked by hypobaric hypoxia. Concomitantly, nitrotyrosine immunoreactivity decreased progressively. In conclusion, activation of the nitrergic system constitutes a cortical response to hypobaric hypoxia and the administration of NOS inhibitors could provide new therapeutic avenues to prevent and/or treat the symptoms produced by hypobaric hypoxia.


Assuntos
Córtex Cerebral/enzimologia , Inibidores Enzimáticos/uso terapêutico , Hipóxia/tratamento farmacológico , Indazóis/uso terapêutico , NG-Nitroarginina Metil Éster/uso terapêutico , Óxido Nítrico Sintase/metabolismo , Altitude , Análise de Variância , Animais , Western Blotting/métodos , Cálcio , Córtex Cerebral/efeitos dos fármacos , Modelos Animais de Doenças , Hipóxia/enzimologia , Hipóxia/patologia , Imuno-Histoquímica/métodos , Masculino , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos , Ratos Wistar , Fatores de Tempo , Tirosina/metabolismo
16.
Neuroscience ; 139(3): 889-98, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16533568

RESUMO

The nitrergic system produces nitric oxide as an atypical neurotransmitter in the nervous system. Nitric oxide is produced from l-arginine through specific enzymes known as nitric oxide synthases. Of these, the more abundant form in neurons is the constitutive neuronal nitric oxide synthase, although the inducible isoform can be expressed as well, especially following stress or other injuries. The excessive formation of nitric oxide results in protein nitration, particularly at tyrosine residues, thus the presence of nitrotyrosine can be used as a marker of nitric oxide production. In previous studies we have shown the distribution of the components of the nitrergic system in the cerebellum of rodents, where neuronal nitric oxide synthase immunoreactivity was present in stellate and basket cells, and occasionally in granule cells. Here, we present evidence that in the sheep, as a model of larger mammals, most cerebellar neurons display an intense immunostaining for neuronal nitric oxide synthase, including unipolar brush cells, and Lugaro and Golgi neurons, which are not immunoreactive in rodents. In addition, weak immunoreactivity for inducible nitric oxide synthase and nitrotyrosine was found in particular cell types, indicating a basal expression for these markers. Our results suggest a larger dependence on the nitrergic system for the cerebella of larger mammals. Since this increase happens in both activating and inhibitory neurons of the cerebellar circuitry, we propose that in these animals there is a higher steady-state regulation of the cerebellum based on nitric oxide.


Assuntos
Cerebelo/metabolismo , Neurônios/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Tirosina/análogos & derivados , Animais , Imuno-Histoquímica , Masculino , Óxido Nítrico/metabolismo , Ovinos , Tirosina/metabolismo
17.
Free Radic Biol Med ; 39(1): 26-50, 2005 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15925277

RESUMO

This review focuses on the effects that ischemia and hypoxia have on the cerebral cortex and the cerebellum during different periods of life. The acute interruption or reduction of cerebral blood flow, that can be induced by several factors and clinical pathologies, reduces available oxygen to the nervous system and this causes either focal or global brain damage, with characteristic biochemical and molecular alterations that can result in permanent or transitory neurological sequelae or even death. Under these circumstances, an increase in the activity of different isoforms of nitric oxide synthase occurs and nitric oxide is produced. This excess of nitric oxide reacts with cellular proteins yielding nitrotyrosine, thus contributing to cerebral damage. This phenomenon has been studied at different stages of perinatal and postnatal development, including aging animals. Both the duration and the intensity of the ischemic injury were evaluated. In all cases there is overproduction of nitric oxide in ischemia, which may represent an effort to reestablish normal blood flow. Unfortunately, in many cases this response becomes excessive and it triggers a cascade of free-radical reactions, leading to modifications of cerebral plasticity and overt injury.


Assuntos
Radicais Livres/metabolismo , Hipóxia-Isquemia Encefálica/fisiopatologia , Envelhecimento/fisiologia , Doença da Altitude/fisiopatologia , Animais , Encéfalo/irrigação sanguínea , Encéfalo/fisiologia , Morte Celular/fisiologia , Córtex Cerebral/embriologia , Córtex Cerebral/crescimento & desenvolvimento , Modelos Animais de Doenças , Humanos , Óxido Nítrico/fisiologia , Óxido Nítrico Sintase/metabolismo , Acidente Vascular Cerebral/fisiopatologia , Vasodilatação/fisiologia
18.
J Comp Neurol ; 378(4): 522-34, 1997 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-9034908

RESUMO

The distribution of neuronal nitric oxide synthase (nNOS) has been studied in the more rostral portion of the lateral ventricle, subfornical organ, area postrema and blood vessels of the rat central nervous system. nNOS was located by means of a specific polyclonal antibody, by using light and electron microscopy. Light microscopy showed immunoreactive varicose nerve fibers and terminal boutons-like structures in the lateral ventricle, positioned in supra- and subependimal areas. The spatial relationships between immunoreactive neuronal processes and the wall of the intracerebral blood vessels were studied. Electron microscopy showed numerous nerve fibers in the wall of the lateral ventricle; many were nNos-immunoreactive and established very close contact with ependymal cells. Immunoreactive neurons and processes were found in the subependymal plate of the ventricular wall, the subfornical organ, the area postrema, and the circularis nucleus of the hypothalamus. In these last three areas, the immunoreactive neurons were found close to the perivascular space of fenestrated and nonfenestrated blood vessels. The nNOS immunoreactivity was localized to the endoplasmic reticulum, cisterns, ribosomes, neurotubules, and in the inner part of the external membrane. In the terminal boutons, the reaction product was found surrounding the vesicle membranes. This distribution showed nNOS as a predominantly membrane-bound protein. The nitrergic nerve fibers present in the wall of the ventricular system might regulate metabolic functions as well as neurotransmission in the subfornical organ, area postrema and circularis nucleus of the hypothalamus.


Assuntos
Ventrículos Cerebrais/enzimologia , Circulação Cerebrovascular , Óxido Nítrico Sintase/metabolismo , Ratos/metabolismo , Frações Subcelulares/enzimologia , Órgão Subfornical/enzimologia , Animais , Vasos Sanguíneos/enzimologia , Imuno-Histoquímica , Masculino , Microscopia Eletrônica , Ratos Wistar , Distribuição Tecidual
19.
Neuroscience ; 116(4): 947-62, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12617936

RESUMO

Adrenomedullin is a multifunctional amidated peptide that has been found in most nuclei of the CNS, where it plays a neuromodulatory role. An adrenomedullin binding protein has recently been found in plasma and characterized as complement factor H. This regulator of the complement system inhibits the progression of the complement cascade and modulates the function of adrenomedullin. Our study shows the ample distribution of factor H immunoreactivity in neurons of telencephalon, diencephalon, mesencephalon, pons, medulla, and cerebellum in the rat CNS, using immunohistochemical techniques for both light and electron microscopy. Factor H immunoreactivity was found in the cytoplasm, but nuclear staining was also a common finding. Some blood vessels and glial cells were also immunoreactive for factor H. Colocalization studies by double immunofluorescence followed by confocal microscopy revealed frequent coexistence of factor H and adrenomedullin immunoreactivities, thus providing morphological evidence for the potential interaction of these molecules in the CNS. The presence of factor H immunoreactivity in glial cells was confirmed by colocalization with glial fibrillary acidic protein. In summary, factor H is highly expressed in the CNS where it could play important roles in regulating adrenomedullin actions and contributing to an intracerebral complement system.


Assuntos
Química Encefálica , Encéfalo/metabolismo , Fator H do Complemento/metabolismo , Peptídeos/metabolismo , Adrenomedulina , Animais , Encéfalo/citologia , Química Encefálica/fisiologia , Fator H do Complemento/análise , Fator H do Complemento/biossíntese , Imunoquímica , Masculino , Peptídeos/análise , Ligação Proteica/fisiologia , Ratos , Ratos Wistar
20.
Neuroscience ; 128(1): 73-89, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15450355

RESUMO

Changes in the amyloid-peptide (Abeta), neuronal and inducible nitric oxide (NO)synthase (nNOS, iNOS), nitrotyrosine, glial fibrillary acidic protein, and lectin from Lycopersicon esculentum (tomato) were investigated in the cerebral cortex of transgenic mice (Tg2576) to amyloid precursor protein (APP), by immunohistochemistry (bright light, confocal, and electron microscopy). The expression of nitrergic proteins and synthesis of nitric oxide were analyzed by immunoblotting and NOS activity assays, respectively. The cerebral cortex of these transgenic mice showed an age-dependent progressive increase in intraneuronal aggregates of Abeta-peptide and extracellular formation of senile plaques surrounded by numerous microglial and reactive astrocytes. Basically, no changes to nNOS reactivity or expression were found in the cortical mantle of either wild or transgenic mice. This reactivity in wild mice corresponded to numerous large type I and small type II neurons. The transgenic mice showed swollen, twisted, and hypertrophic preterminal and terminal processes of type I neurons, and an increase of the type II neurons. The calcium-dependent NOS enzymatic activity was higher in wild than in the transgenic mice. The iNOS reactivity, expression and calcium-independent enzymatic activity increased in transgenic mice with respect to wild mice, and were related to cortical neurons and microglial cells. The progressive elevation of NO production resulted in a specific pattern of protein nitration in reactive astrocytes. The ultrastructural study carried out in the cortical mantle showed that the neurons contained intracellular aggregates of Abeta-peptide associated with the endoplasmic reticulum, mitochondria, and Golgi apparatus. The endothelial vascular cells also contained Abeta-peptide deposits. This transgenic model might contribute to understand the role of the nitrergic system in the biological changes related to neuropathological progression of Alzheimer's disease.


Assuntos
Precursor de Proteína beta-Amiloide/metabolismo , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Neurônios/metabolismo , Óxido Nítrico/metabolismo , Tirosina/análogos & derivados , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Animais , Astrócitos/metabolismo , Astrócitos/patologia , Western Blotting , Córtex Cerebral/ultraestrutura , Modelos Animais de Doenças , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Imuno-Histoquímica , Camundongos , Camundongos Transgênicos , Microscopia Confocal , Neurônios/patologia , Neurônios/ultraestrutura , Óxido Nítrico Sintase/metabolismo , Placa Amiloide/metabolismo , Placa Amiloide/patologia , Tirosina/metabolismo
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