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1.
Cureus ; 14(7): e26861, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35978756

RESUMO

Paraneoplastic neuropathy, including pruritis, remains a vexing problem as it often does not resolve even with successful treatment of cancer. Scrambler Therapy is a superficial form of neuromodulation that replaces the pain signal with "non-pain information" that is approved for chronic and neuropathic pain, with few side effects. We report here two cases of paraneoplastic neuropathy, one with additional pruritis, that both responded satisfactorily to Scrambler Therapy with no side effects.

2.
AJNR Am J Neuroradiol ; 39(11): 2034-2036, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30262647

RESUMO

Central nervous system vasculitides are elusive diseases that are challenging to diagnose because brain biopsies have high false-negative rates. We sought to test the ability of contrast-enhanced, high-resolution 3D vessel wall MR imaging to identify vascular inflammation and direct open biopsies of intracranial target vessels and adjacent brain parenchyma. Eight of 9 specimens revealed vascular inflammation. We conclude that vessel wall MR imaging can identify inflamed intracranial vessels, enabling precise localization of biopsy targets.


Assuntos
Biópsia Guiada por Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Vasculite do Sistema Nervoso Central/diagnóstico por imagem , Vasculite do Sistema Nervoso Central/cirurgia , Humanos , Imageamento Tridimensional/métodos
5.
Science ; 360(6385): p. 158-159, 2018.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib15305
6.
AJNR Am J Neuroradiol ; 38(9): 1814-1819, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28729296

RESUMO

BACKGROUND AND PURPOSE: The early diagnosis of spinal vascular malformations suffers from the nonspecificity of their clinical and radiologic presentations. Spinal angiography requires a methodical approach to offer a high diagnostic yield. The prospect of false-negative studies is particularly distressing when addressing conditions with a narrow therapeutic window. The purpose of this study was to identify factors leading to missed findings or inadequate studies in patients with spinal vascular malformations. MATERIALS AND METHODS: The clinical records, laboratory findings, and imaging features of 18 patients with spinal arteriovenous fistulas and at least 1 prior angiogram read as normal were reviewed. The clinical status was evaluated before and after treatment by using the Aminoff-Logue Disability Scale. RESULTS: Eighteen patients with 19 lesions underwent a total of 30 negative spinal angiograms. The lesions included 9 epidural arteriovenous fistulas, 8 dural arteriovenous fistulas, and 2 perimedullary arteriovenous fistulas. Seventeen patients underwent endovascular (11) or surgical (6) treatment, with a delay ranging between 1 week and 32 months; the Aminoff-Logue score improved in 13 (76.5%). The following factors were identified as the causes of the inadequate results: 1) lesion angiographically documented but not identified (55.6%); 2) region of interest not documented (29.6%); or 3) level investigated but injection technically inadequate (14.8%). CONCLUSIONS: All the angiograms falsely reported as normal were caused by correctible, operator-dependent factors. The nonrecognition of documented lesions was the most common cause of error. The potential for false-negative studies should be reduced by the adoption of rigorous technical and training standards and by second opinion reviews.


Assuntos
Malformações Vasculares do Sistema Nervoso Central/diagnóstico , Angiografia por Ressonância Magnética , Adulto , Idoso , Idoso de 80 Anos ou mais , Reações Falso-Negativas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medula Espinal/anormalidades
7.
Eur J Clin Microbiol Infect Dis ; 35(12): 2047-2051, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27558110

RESUMO

Plasmid-mediated quinolone resistance mechanisms have become increasingly prevalent among Enterobacteriaceae strains since the 1990s. Among these mechanisms, AAC(6')-Ib-cr is the most difficult to detect. Different detection methods have been developed, but they require expensive procedures such as Sanger sequencing, pyrosequencing, polymerase chain reaction (PCR) restriction, or the time-consuming phenotypic method of Wachino. In this study, we describe a simple matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) method which can be easily implemented in clinical laboratories that use the MALDI-TOF technique for bacterial identification. We tested 113 strains of Enterobacteriaceae, of which 64 harbored the aac(6')-Ib-cr gene. We compared two MALDI-TOF strategies, which differed by their norfloxacin concentration (0.03 vs. 0.5 g/L), and the method of Wachino with the PCR and sequencing strategy used as the reference. The MALDI-TOF strategy, performed with 0.03 g/L norfloxacin, and the method of Wachino yielded the same high performances (Se = 98 %, Sp = 100 %), but the turnaround time of the MALDI-TOF strategy was faster (<5 h), simpler, and inexpensive (<1 Euro). Our study shows that the MALDI-TOF strategy has the potential to become a major method for the detection of many different enzymatic resistance mechanisms.


Assuntos
Antibacterianos/metabolismo , Técnicas Bacteriológicas/métodos , Biotransformação , Farmacorresistência Bacteriana , Enterobacteriaceae/efeitos dos fármacos , Norfloxacino/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Antibacterianos/farmacologia , Enterobacteriaceae/metabolismo , Norfloxacino/farmacologia , Sensibilidade e Especificidade , Fatores de Tempo
8.
AJNR Am J Neuroradiol ; 35(6): 1226-31, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24407272

RESUMO

BACKGROUND AND PURPOSE: This study was prompted by recurrent angiographic observations of focal stenoses involving the proximal segment of the left upper thoracic intersegmental arteries, a few centimeters distal to their origin. The purpose was to investigate the nature and prevalence of this anomaly. MATERIALS AND METHODS: The existence of non-ostial thoracic intersegmental artery stenoses was evaluated in 50 angiograms; the contribution of stenosed branches to the anterior spinal artery was recorded. Angiograms performed in 3 patients with right-sided aortas were also reviewed. The topographic relationships of the upper thoracic intersegmental artery with surrounding structures were investigated in 3 cadavers. RESULTS: Thirty-seven non-ostial stenoses were found in 26 patients (52%), predominantly on the left side (92%), between T3 and T8, most frequently at T4 and T5 (54%). Severe lesions were observed in 10% of cases. Patients with stenoses had fewer detectable anterior radiculomedullary arteries between T3 and T5 (35% versus 54%). Upper intersegmental artery stenoses, documented on the left side of all 3 specimens, appeared to be caused by the recurrent path of these intersegmental arteries related to the leftward position of the thoracic aorta, and by their course around reinforced paramedian longitudinal strands of the endothoracic fascia. CONCLUSIONS: Upper thoracic intersegmental artery stenoses are frequent. They result from the leftward deviation of the descending aorta and the existence of a fixed point along the course of the intersegmental arteries related to the endothoracic fascia. Because contributors to the spinal vascularization often originate at similar levels, these stenoses may play a role in the susceptibility of the upper and midthoracic spinal cord to ischemia.


Assuntos
Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/diagnóstico por imagem , Isquemia do Cordão Espinal/diagnóstico por imagem , Isquemia do Cordão Espinal/etiologia , Tórax/irrigação sanguínea , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia/métodos , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia Torácica/métodos , Adulto Jovem
9.
Exp Neurol ; 241: 95-104, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23195594

RESUMO

The aim of this study was to search for neuropathological changes in postmortem brain tissue of individuals with cervical dystonia (CD). Multiple regions of formalin-preserved brains were collected from patients with CD and controls and examined with an extensive battery of histopathological stains in a two-stage study design. In stage one, 4 CD brains underwent a broad screening neuropathological examination. In stage two, these 4 CD brains were combined with 2 additional CD brains, and the subjective findings were quantified and compared to 16 age-matched controls. The initial subjective neuropathological assessment revealed only two regions with relatively consistent changes. The substantia nigra had frequent ubiquitin-positive intranuclear inclusions known as Marinesco bodies. Additionally, the cerebellum showed patchy loss of Purkinje cells, areas of focal gliosis and torpedo bodies. Other brain regions showed minor or inconsistent changes. In the second stage of the analysis, quantitative studies failed to reveal significant differences in the numbers of Marinesco bodies in CD versus controls, but confirmed a significantly lower Purkinje cell density in CD. Molecular investigations revealed 4 of the CD cases and 2 controls to harbor sequence variants in non-coding regions of THAP1, and these cases had lower Purkinje cell densities regardless of whether they had CD. The findings suggest that subtle neuropathological changes such as lower Purkinje cell density may be found in primary CD when relevant brain regions are investigated with appropriate methods.


Assuntos
Encéfalo/patologia , Torcicolo/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas Reguladoras de Apoptose/genética , Encéfalo/metabolismo , Proteínas de Ligação a DNA/genética , Feminino , Humanos , Corpos de Inclusão Intranuclear/metabolismo , Corpos de Inclusão Intranuclear/patologia , Corpos de Lewy/patologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/genética , Células de Purkinje/metabolismo , Células de Purkinje/patologia , Torcicolo/genética , Ubiquitina/metabolismo , Adulto Jovem
10.
Neurology ; 75(15): 1318-25, 2010 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-20810997

RESUMO

OBJECTIVE: Retinal nerve fiber layer (RNFL) abnormalities detected by optical coherence tomography (OCT) are useful markers for axonal loss and visual dysfunction in multiple sclerosis (MS), but their role in routine clinical management is not well-studied. METHODS: Clinical and OCT examinations were performed on 240 patients attending a neurology clinic. Using OCT 5th percentile to define abnormal RNFL thickness, we compared eyes classified by neurologists as having optic atrophy to RNFL thickness, and afferent pupillary defect (APD) to RNFL thickness ratios of eye pairs. RESULTS: Mean RNFL thickness was less in eyes classified by neurologists as having optic atrophy (79.4 ± 21 µm; n=63) vs those without (97.0 ± 15 µm; n=417; p < 0.001, t test) and in eyes with an APD (84.1 ± 16 µm; n=44) than without an APD (95.8 ± 17 µm; n=436; p < 0.001). Physicians' diagnostic accuracy for detecting pallor in eyes with an abnormal RNFL thickness was 79% (sensitivity=0.56; specificity=0.82). Accuracy for detecting a RAPD in patients with mean RNFL ratio (affected eye to unaffected eye) <0.90 was 73% (sensitivity=0.30; specificity=0.86). Ability to detect visual pathway injury via assessment of atrophy and APD differed between neurologists. CONCLUSIONS: OCT reveals RNFL abnormality in many patients in whom eyes are not classified by neurologic examiners as having optic atrophy. Further study is needed to define the role of OCT measures in the context of examinations for optic atrophy and APD by neuroophthalmologists. OCT-measured RNFL thickness is likely to have an important future role in the clinical setting.


Assuntos
Fibras Nervosas/patologia , Nervo Óptico/patologia , Distúrbios Pupilares/patologia , Tomografia de Coerência Óptica/métodos , Adulto , Olho/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Transtornos da Visão
12.
J Pharmacol Exp Ther ; 322(1): 16-22, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17400887

RESUMO

Autism is a neurodevelopmental disorder presenting before 3 years of age with deficits in communication and social skills and repetitive behaviors. In addition to genetic influences, recent studies suggest that prenatal drug or chemical exposures are risk factors for autism. Terbutaline, a beta2-adrenoceptor agonist used to arrest preterm labor, has been associated with increased concordance for autism in dizygotic twins. We studied the effects of terbutaline on microglial activation in different brain regions and behavioral outcomes in developing rats. Newborn rats were given terbutaline (10 mg/kg) daily on postnatal days (PN) 2 to 5 or PN 11 to 14 and examined 24 h after the last dose and at PN 30. Immunohistochemical studies showed that administration of terbutaline on PN 2 to 5 produced a robust increase in microglial activation on PN 30 in the cerebral cortex, as well as in cerebellar and cerebrocortical white matter. None of these effects occurred in animals given terbutaline on PN 11 to 14. In behavioral tests, animals treated with terbutaline on PN 2 to 5 showed consistent patterns of hyper-reactivity to novelty and aversive stimuli when assessed in a novel open field, as well as in the acoustic startle response test. Our findings indicate that beta2-adrenoceptor overstimulation during an early critical period results in microglial activation associated with innate neuroinflammatory pathways and behavioral abnormalities, similar to those described in autism. This study provides a useful animal model for understanding the neuropathological processes underlying autism spectrum disorders.


Assuntos
Agonistas Adrenérgicos beta/toxicidade , Transtorno Autístico/induzido quimicamente , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Microglia/efeitos dos fármacos , Terbutalina/toxicidade , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Feminino , Masculino , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptores Adrenérgicos beta 2/fisiologia , Reflexo de Sobressalto/efeitos dos fármacos
13.
Neurology ; 67(3): 383-8, 2006 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-16894096

RESUMO

OBJECTIVE: To describe challenges in diagnosis and management of patients with clinical syndromes of immune reconstitution inflammatory syndrome (IRIS) involving the CNS. METHODS: The authors describe three patients with clinically distinct neurologic manifestations of IRIS with HIV infection who presented as diagnostic and therapeutic challenges. RESULTS: One patient with cryptococcal meningitis developed acute cerebellitis with mass effect and brainstem compression. Corticosteroid therapy was associated with complete resolution of the cerebellar lesion but the patient developed VZV encephalitis. Another patient with progressive multifocal leukoencephalopathy developed subacute progression of focal neurologic deficits associated with contrast enhancing lesions on brain MRI. This patient had spontaneous resolution of the lesion but was left with residual deficits. One patient developed a progressive dementing syndrome and deterioration over several months resulting in coma during combination antiretroviral therapy. A brain biopsy in this latter patient showed massive infiltration of T lymphocytes predominantly of the CD8 subtype. This patient had a significant improvement with corticosteroids and change in antiretroviral regimen although she was left with residual cognitive impairment. CONCLUSIONS: Immune reconstitution inflammatory syndrome should be suspected in patients who show clinical or radiologic deterioration following initiation of antiretroviral therapy accompanied with improvement in CD4 cell count and viral load. Some patients may respond to a brief course of treatment with corticosteroids.


Assuntos
Corticosteroides/uso terapêutico , Doenças Autoimunes do Sistema Nervoso/tratamento farmacológico , Doenças Autoimunes do Sistema Nervoso/etiologia , Infecções por HIV/complicações , Infecções Oportunistas Relacionadas com a AIDS , Terapia Antirretroviral de Alta Atividade , Doenças Autoimunes do Sistema Nervoso/virologia , Contagem de Linfócito CD4 , Doenças do Sistema Nervoso Central/etiologia , Doenças do Sistema Nervoso Central/virologia , Infecções por HIV/tratamento farmacológico , Humanos , Carga Viral
14.
Neurology ; 63(4): 626-30, 2004 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-15326233

RESUMO

BACKGROUND: Polymorphisms in apolipoprotein E have been associated with worse prognoses in numerous neurodegenerative conditions, including HIV dementia (HIVD). Despite these correlative observations, there has been little evidence suggesting a mechanism whereby the expression of ApoE4 renders neurons susceptible to insult. METHODS: Electrospray ionization tandem mass spectrometry was used to quantify levels of sphingolipids and sterols in brains of HIVD patients. Data were stratified according to APOE genotype. RESULTS: The authors found evidence of dysregulated lipid and sterol metabolism in HIVD patients with an APOE4 genotype. They also found elevations of sphingomyelin, ceramide, and cholesterol in the medial frontal cortex, parietal cortex, and cerebellum of HIVD patients with an APOE3/4 or APOE4/4 genotype compared with HIVD patients with an APOE3/3 genotype. There was no difference in the number of astrocytes or activated microglia in any brain region of the two patient populations, suggesting that modification of lipid metabolism in HIVD patients with an APOE4 genotype was not the result of increased CNS inflammation. CONCLUSIONS: HIV dementia patients with an APOE4 genotype may be sensitized to neural insults because of dysregulations in lipid metabolism.


Assuntos
Complexo AIDS Demência/metabolismo , Apolipoproteínas E/fisiologia , Química Encefálica , Esfingolipídeos/metabolismo , Esteróis/metabolismo , Complexo AIDS Demência/líquido cefalorraquidiano , Complexo AIDS Demência/genética , Adulto , Apolipoproteína E4 , Ceramidas/metabolismo , Colesterol/metabolismo , Predisposição Genética para Doença , Genótipo , Humanos , Inflamação , Peroxidação de Lipídeos , Masculino , Lipídeos de Membrana/metabolismo , Estresse Oxidativo , Fosfolipídeos/metabolismo
16.
Neuropathol Appl Neurobiol ; 29(6): 584-95, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14636165

RESUMO

Haematogenous leucocytes enter the central nervous system (CNS) during diverse disorders of varied aetiologies. Understanding the trafficking cues that mediate CNS leucocyte infiltration might promote the development of flexible and selective means to modulate inflammation to achieve clinical benefit. The trafficking machinery of leucocytes has been elucidated during the past decade and consists of cell-surface adhesion molecules, chemoattractant cytokines (chemokines) and their receptors. Recent work in our laboratory characterized chemokine receptors found on T lymphocytes and monocytes in brain sections from subjects with one pathological subtype of multiple sclerosis (MS), an immune-mediated inflammatory demyelinating disease. In these tissues, the types 1 and 5 CC chemokine receptors (CCR1 and CCR5) were detected on perivascular monocytic cells whereas only CCR5 was present on parenchymal macrophages. The type 3 CXC chemokine receptor (CXCR3) was present on virtually all CD3-positive T cells. In the current study, we evaluated the expression of these receptors on the infiltrating cells present in cases of other inflammatory CNS disorders including those of dysimmune, infectious, neoplastic, and vascular aetiology. Perivascular and parenchymal monocytic cells expressed CCR1 in all cases and CXCR3 was consistently present on a substantial proportion of CD3+ T cells. The occurrence of CCR5 on parenchymal macrophages was much less uniform across the varied disorders. These data implicate CCR1 in monocyte infiltration of the CNS and are consistent with reports of studies in CCR1-deficient mice. CXCR3 is also likely to play a role in accumulation of T cells in the inflamed CNS. By contrast, our findings suggest that regulation of CCR5 on phagocytic macrophages may be contingent on the lesion environment.


Assuntos
Encefalopatias/patologia , Inflamação/patologia , Leucócitos Mononucleares/metabolismo , Receptores de Quimiocinas/metabolismo , Adolescente , Adulto , Idoso , Encefalopatias/imunologia , Complexo CD3/metabolismo , Calgranulina B/metabolismo , Criança , Humanos , Imuno-Histoquímica , Inflamação/imunologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
17.
Neurology ; 57(8): 1396-401, 2001 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-11673579

RESUMO

OBJECTIVE: To examine the association between HIV RNA levels, patterns of antiretroviral resistance, and neurologic status. METHODS: Autopsy samples from 13 HIV-infected subjects were examined for HIV-1 viral RNA (vRNA), and viral reverse transcriptase (RT) genotype was determined. All subjects had been clinically characterized using standard instruments before death. RESULTS: The median HIV-1 vRNA level in brain samples from subjects with moderate dementia was 7.79 log(10) copies/g (range 5.56 to 9.75 log(10) copies/g) compared with 5.44 log(10) copies/g (range 3.51 to 9.32 log(10) copies/g) for mildly demented subjects and 4.87 log(10) copies/g (3.51 to 6.86 log(10) copies/g) for those obtained from nondemented individuals. There were differences between subjects with moderate dementia and nondemented subjects (p = 0.0002) and between subjects with moderate and mild dementia (p = 0.0128). No significant differences among the groups were observed for vRNA levels in peripheral tissues. Some demented subjects had relatively low levels of HIV-1 vRNA, and paradoxically some nondemented subjects had high vRNA brain levels. Little subject effect in vRNA was noted in peripheral regions, but high regional variation in vRNA was noted within the brain. Patterns of the major zidovudine (ZDV) RT mutations in brain and peripheral tissues were concordant in most subjects. Subjects with longer duration of exposure to ZDV tended to have lower brain vRNA levels and a greater number of RT mutations than those with limited to no exposure. CONCLUSIONS: The presence and severity of HIV dementia correlates with the levels of productive HIV replication within the brain. Other pathophysiologic events (including macrophage activation) probably also contribute to neurologic dysfunction.


Assuntos
Complexo AIDS Demência/tratamento farmacológico , Fármacos Anti-HIV/uso terapêutico , HIV-1/genética , Zidovudina/uso terapêutico , Complexo AIDS Demência/virologia , Encéfalo/virologia , Contagem de Linfócito CD4 , Transcriptase Reversa do HIV/genética , HIV-1/isolamento & purificação , Humanos , Imunidade Inata , Mutação , RNA Viral/análise , Índice de Gravidade de Doença , Replicação Viral
18.
Arch Neurol ; 58(10): 1561-6, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11594913

RESUMO

To provide a venue for a comprehensive multidisciplinary review of the current state of knowledge regarding the human immunodeficiency virus-associated peripheral neuropathies and to provide the institute with guidance in formulating future research initiatives, the National Institute of Neurological Disorders and Stroke (Bethesda, Md) convened a workshop on September 18 through 19, 2000. The participants were chosen from various disciplines and included clinicians, pathologists, neurobiologists, neurophysiologists, virologists, and neuroimmunologists. The present article summarizes the highlights of the meeting and includes the recommendations developed by the participants for future research. As might be expected in a rapidly evolving scientific field, the meeting was characterized by a lively and far-ranging discussion of data interpretation, experimental approaches, and priorities for future research. However, the recommendations presented at the end of this article constitute a consensus judgment reached by all of the participants of the most important areas for future research.


Assuntos
Síndrome da Imunodeficiência Adquirida/fisiopatologia , Infecções por HIV/tratamento farmacológico , HIV/fisiologia , Neuralgia/fisiopatologia , Dor/fisiopatologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Animais , Infecções por HIV/fisiopatologia , HIV-1 , Humanos , Hiperalgesia/fisiopatologia , Isquemia , Modelos Animais , Compressão Nervosa , Neuralgia/virologia
19.
J Clin Invest ; 108(3): 425-35, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11489936

RESUMO

Stromal-derived cell factor-1 alpha (SDF-1 alpha; CXCL12) and its receptor, CXCR4, are constitutively expressed on neuroepithelial cells and are believed to be involved in both development and pathological processes, such as AIDS-associated neurologic disorders. Here, we demonstrate that SDF-1 alpha activates NF-kappa B, stimulates production of chemokines and cytokines, and induces cell death in primary astrocytes, effects that depend on ongoing secretion of TNF-alpha. SDF-1 alpha upregulated TNF-alpha mRNA and protein secretion, as well as TNF receptor 2 expression. TNF-alpha treatment mimicked SDF-1 alpha induction of NF-kappa B, IL-1 alpha/beta, and RANTES, as well as cell death; neutralizing antibodies against TNF-alpha opposed these responses. We also found that SDF-1 alpha activated Erk1 and Erk2 (Erk1/2) MAPK in a biphasic fashion. Early Erk1/2 activation was stimulated directly by SDF-1 alpha and late activation was mediated by TNF-alpha. PD98059 suppression of early Erk1/2 activation correlated with reduction of SDF-1 alpha-induced TNF-alpha expression. Late Erk1/2 activation was involved in TNF-alpha-stimulated NF-kappa B activation and cytokine induction. SDF-1 alpha was induced in reactive CXCR4-positive astrocytes near axotomized spinal cord motor neurons, consistent with autocrine SDF-1/CXCR4 signaling in these cells. We propose that these novel effects of SDF-1 alpha are relevant to the pathogenic and developmental roles of SDF-1 alpha in the CNS.


Assuntos
Astrócitos/efeitos dos fármacos , Astrócitos/fisiologia , Quimiocinas CXC/farmacologia , Proteínas I-kappa B , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/fisiologia , Animais , Antígenos CD/genética , Astrócitos/citologia , Morte Celular/efeitos dos fármacos , Células Cultivadas , Quimiocina CCL5/genética , Quimiocina CXCL12 , Quimiocinas CXC/genética , Quimiocinas CXC/fisiologia , Proteínas de Ligação a DNA/metabolismo , Ativação Enzimática/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Interleucina-1/genética , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Inibidor de NF-kappaB alfa , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores CXCR4/metabolismo , Receptores do Fator de Necrose Tumoral/genética , Receptores Tipo II do Fator de Necrose Tumoral , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , Transdução de Sinais , Fator de Necrose Tumoral alfa/genética
20.
J Peripher Nerv Syst ; 6(1): 21-7, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11293804

RESUMO

HIV-associated neuropathies (HIV-N) have become the most frequent neurological disorder associated with HIV infection. The most common forms of HIV-N are the distal sensory polyneuropathy (DSP) and antiretroviral toxic neuropathies (ATN), disorders characterized mostly by sensory symptoms that include spontaneous or evoked pain that follow a subacute or chronic course. The main pathological features that characterize DSP and ATN include "dying back" axonal degeneration of long axons in distal regions, loss of unmyelinated fibers, and variable degree of macrophage infiltration in peripheral nerves and dorsal root ganglia. Marked activation of macrophages as well as the effect of pro-inflammatory cytokines appear to be the main immunopathogenic factors in DSP. Interference with DNA synthesis and mitochondrial abnormalities produced by nucleoside antiretrovirals have been hypothesized as pathogenic factors involved in ATN. The use of skin biopsy has become a useful tool in the evaluation of HIV-N. Reduction in fiber density, increased frequency of fiber varicosities and fiber fragmentation are prominent features of skin biopsies from patients with HIV-N. Other forms of HIV-N include acute or chronic inflammatory polyneuropathies, uncommon disorders that may ocur during seroconversion or early stages of HIV infection. Opportunisitic infections, mostly associated with cytomegalovirus or herpes zoster virus infection occur in late stages of AIDS and produce characteristic clinical features such as mononeuritis multiple or radiculopathies.


Assuntos
Infecções por HIV/patologia , Doenças do Sistema Nervoso Periférico/patologia , Doenças do Sistema Nervoso Periférico/virologia , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Infecções por HIV/tratamento farmacológico , Humanos , Doenças do Sistema Nervoso Periférico/induzido quimicamente
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