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1.
Clin Genet ; 95(2): 253-261, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-28857140

RESUMO

The Say-Barber-Biesecker-Young-Simpson variant of Ohdo syndrome (SBBYSS) and Genitopatellar syndrome (GTPTS) are 2 rare but clinically well-described diseases caused by de novo heterozygous sequence variants in the KAT6B gene. Both phenotypes are characterized by significant global developmental delay/intellectual disability, hypotonia, genital abnormalities, and patellar hypoplasia/agenesis. In addition, congenital heart defects, dental abnormalities, hearing loss, and thyroid anomalies are common to both phenotypes. This broad clinical overlap led some authors to propose the concept of KAT6B spectrum disorders. On the other hand, some clinical features could help to differentiate the 2 disorders. Furthermore, it is possible to establish a genotype-phenotype correlation when considering the position of the sequence variant along the gene, supporting the notion of the 2 disorders as really distinct entities.


Assuntos
Blefarofimose/diagnóstico , Blefarofimose/etiologia , Hipotireoidismo Congênito/diagnóstico , Hipotireoidismo Congênito/etiologia , Suscetibilidade a Doenças , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/etiologia , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/etiologia , Instabilidade Articular/diagnóstico , Instabilidade Articular/etiologia , Alelos , Biomarcadores , Diagnóstico Diferencial , Fácies , Estudos de Associação Genética , Predisposição Genética para Doença , Variação Genética , Humanos , Fenótipo
2.
Clin Genet ; 93(3): 545-556, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28556904

RESUMO

Whole exome sequencing (WES) has made the identification of causative SNVs/InDels associated with rare Mendelian conditions increasingly accessible. Incorporation of softwares allowing CNVs detection into the WES bioinformatics pipelines may increase the diagnostic yield. However, no standard protocols for this analysis are so far available and CNVs in non-coding regions are totally missed by WES, in spite of their possible role in the regulation of the flanking genes expression. So, in a number of cases the diagnostic workflow contemplates an initial investigation by genomic arrays followed, in the negative cases, by WES. The opposite workflow may also be applied, according to the familial segregation of the disease. We show preliminary results for a diagnostic application of a single next generation sequencing panel permitting the concurrent detection of LOH and variations in sequences and copy number. This approach allowed us to highlight compound heterozygosity for a CNV and a sequence variant in a number of cases, the duplication of a non-coding region responsible for sex reversal, and a whole-chromosome isodisomy causing reduction to homozygosity for a WFS1 variant. Moreover, the panel enabled us to detect deletions, duplications, and amplifications with sensitivity comparable to that of the most widely used array-CGH platforms.


Assuntos
Predisposição Genética para Doença , Testes Genéticos , Variação Genética , Estudo de Associação Genômica Ampla , Sequenciamento de Nucleotídeos em Larga Escala , Adolescente , Adulto , Criança , Pré-Escolar , Variações do Número de Cópias de DNA , Feminino , Testes Genéticos/métodos , Estudo de Associação Genômica Ampla/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Mutação INDEL , Lactente , Perda de Heterozigosidade , Masculino , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Adulto Jovem
3.
J Biol Regul Homeost Agents ; 31(4): 1087-1093, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29254319

RESUMO

Bergamot polyphenolic fraction (BPF) has been shown to positively modulate several mechanisms involved in metabolic syndrome, suggesting its use in therapy. In particular, it is able to induce a significant amelioration of serum lipid profile in hyperlipemic patients at different levels. The purpose of our study was to investigate the effect of BPF on cholesterol absorption physiologically mediated by pancreatic cholesterol ester hydrolase (pCEH). An in vitro activity assay was performed to study the effect of BPF on pCEH, whereas the rate of cholesterol absorption was evaluated through in vivo studies. In particular, male, Sprague-Dawley rats (200–225 g) were fed either normal chow or chow supplemented with 0.5% cholic acid, 5.5% peanut oil, and varying amounts of cholesterol (0 to 1.5%). BPF (10 mg/Kg) was daily administrated by means of a gastric gavage to animals fed with lipid supplemented diet for 4 weeks and, at the end of the study, plasma lipids and liver cholesteryl esters were measured in all experimental groups. Our results show that BPF was able to inhibit pCEH activity and this effect was confirmed, in vivo, via detection of lymphatic cholesteryl ester in rats fed with a cholesterol-rich diet. This evidence clarifies a further mechanism responsible for the hypolipemic properties of BPF previously observed in humans, confirming its beneficial effect in the therapy of hypercholesterolemia and in the treatment of metabolic syndrome.


Assuntos
Suplementos Nutricionais , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/farmacologia , Óleos de Plantas/farmacologia , Esterol Esterase/antagonistas & inibidores , Animais , Colesterol/administração & dosagem , Colesterol/sangue , Ésteres do Colesterol/sangue , Ácido Cólico/administração & dosagem , Ácido Cólico/sangue , Absorção Gastrointestinal/fisiologia , Humanos , Hiperlipidemias/metabolismo , Hiperlipidemias/patologia , Hipolipemiantes/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Síndrome Metabólica/tratamento farmacológico , Síndrome Metabólica/metabolismo , Síndrome Metabólica/patologia , Óleos de Plantas/metabolismo , Ratos , Ratos Sprague-Dawley , Esterol Esterase/metabolismo , Triglicerídeos/sangue
4.
Clin Genet ; 92(4): 440-443, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28266014

RESUMO

Prader-Willi syndrome is a complex condition caused by lack of expression of imprinted genes in the paternally derived region of chromosome 15 (15q11q13). A small number of patients with Prader-Willi phenotype have been discovered to have narrow deletions, not encompassing the whole critical region, but only the SNORD116 cluster, which includes genes codifying for small nucleolar RNAs. This kind of deletion usually is not detected by the classic DNA methylation analysis test. We present the case of a male patient with a mild Prader-Willi phenotype and a small deletion including SNORD116, diagnosed by methylation-sensitive multiplex ligation-dependent probe amplification (MLPA. The patient showed neonatal hypotonia, hyperphagia, obesity, central hypogonadism, hypothyroidism, strabismus. Stature and intellectual development are within the normal range. The presence of macrocephaly, observed in other cases of SNORD116 deletions as well, is uncommon for the classic phenotype of the syndrome.


Assuntos
Megalencefalia/genética , Síndrome de Prader-Willi/genética , RNA Nucleolar Pequeno/genética , Adolescente , Metilação de DNA/genética , Deleção de Genes , Impressão Genômica/genética , Humanos , Masculino , Megalencefalia/fisiopatologia , Fenótipo , Síndrome de Prader-Willi/fisiopatologia
5.
J Ultrasound ; 14(1): 1-6, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23397005

RESUMO

INTRODUCTION: The interobserver variability of the sonographic assessment of Focal Bladder Wall Abnormalities (FBWA) between two physicians with different levels of experience was evaluated prospectively. MATERIALS AND METHODS: In the same session the two operators examined independently the urinary bladder of 87 consecutive patients (Mean Age 68 yrs; range 33-80; 75 Males; 15 Females) who underwent cystoscopy within 1-2 days. Before beginning the study, the two observers standardized the process for US exam. Weighted kappa statistics were used to determine the degree of agreement as to the presence, size, location and number of FBWA detected at cystoscopy. RESULTS: the highest level of agreement (k = 1) was reached on the presence of FBWA, whereas a substantial agreement was reached on size (k = 0.78), number (k = 0.72) and location (k = 0.62) of FBWA. CONCLUSIONS: In this study the gap in US experience between two operators did not emerge in assessing FBWA, provided a standardized technical approach is pursued.

6.
Br J Biomed Sci ; 67(3): 105-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20973403

RESUMO

Electrochemical activation (ECA) has been developed as a quick and efficient method of hypochlorite production, and many claim increased efficacy when compared to conventional disinfectant solutions. Numerous potential applications, including hospital disinfection, waste-water treatment, routine drinking water disinfection and biological decontamination have been suggested. In this study, three solutions were produced by electrochemical activation of 0.5% NaCl and compared to commercially available NaOCl. The NaOCl concentration and pH of each solution was measured, and the minimum bactericidal concentration of each was determined using seven common microbial pathogens. All solutions were effective, the most significant of which was the ECA anolyte solution. This is notable due to its neutral pH and antimicrobial efficacy that is four times that of commercially available NaOCl. This process may lead to production of a highly effective yet non-caustic disinfectant that would have countless scientific, medical, military and public health applications.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Técnicas Eletroquímicas/métodos , Espécies Reativas de Oxigênio/farmacologia , Hipoclorito de Sódio/farmacologia , Antibacterianos/síntese química , Desinfetantes/síntese química , Desinfetantes/farmacologia , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Hipoclorito de Sódio/síntese química
7.
J Cardiovasc Surg (Torino) ; 50(2): 205-12, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19329917

RESUMO

AIM: Outcomes after surgery for acute type A aortic dissection in the octogenarian are controversial. To analyze this issue further, the authors reviewed their experience in the hope of finding ways to improve results in these high-risk patients. METHODS: Between April 1990 and November 2006, 319 consecutive patients underwent emergency surgery for acute type A aortic dissection at the San Martino University Hospital of Genoa (Italy). Among them, 23 (7%) patients were aged 80 years or older (mean age 82 years, range 80 to 86 years) and represent the study population. On admission 7 patients (30%) had preoperative shock, 1 needed cardiopulmonary resuscitation, 7 (30%) had a neurological deficit, 2 (9%) had acute renal failure. Deep hypothermic circulatory arrest was performed in 19 patients (83%). Surgical procedures included isolated replacement of the ascending aorta in all patients associated with root replacement in 2 (9%) and total aortic arch replacement in 5 (22%). Median follow up was 4.1 years (range 3 to 83 months). RESULTS: Hospital mortality was 61% (14 of 23 patients). Late mortality was 11% (1 of 9 survivors). Stepwise logistic regression identified the extension of surgery to the arch as independent risk factors for hospital death. Fourteen patients (61%) had 1 or more postoperative complications. Overall survival was 39+/-10% and 33+/-10% after 1 and 5 years respectively. CONCLUSIONS: Surgery for acute type A aortic dissection in the octogenarian shows high hospital mortality but satisfactory long-term survival among discharged patients. A less aggressive approach should increase the outcomes of surgically managed patients.


Assuntos
Aneurisma Aórtico/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular , Acessibilidade aos Serviços de Saúde , Serviços de Saúde para Idosos , Doença Aguda , Idoso de 80 Anos ou mais , Dissecção Aórtica/complicações , Dissecção Aórtica/mortalidade , Aneurisma Aórtico/complicações , Aneurisma Aórtico/mortalidade , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/mortalidade , Parada Circulatória Induzida por Hipotermia Profunda , Feminino , Mortalidade Hospitalar , Humanos , Itália/epidemiologia , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Reoperação , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
8.
J Ultrasound ; 12(3): 101-6, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23396117

RESUMO

INTRODUCTION: The aim of the present study was to highlight the sonographic and clinical characteristics of large (≥30 mm in diameter) scar endometriomas near Pfannenstiel incisions, assuming that large size is a marker of delayed diagnosis. METHODS: We compared clinical, ultrasound (US) and color Doppler findings in 13 patients (mean age 31.3 years) with 13 large scar endometriomas (L-SEs) (mean lesion diameter 41.8 mm; range 30-60 mm) and 17 women (mean age 30.7 years) with 19 small scar endometriomas (S-SEs) (mean lesion size 18.3 mm; range 7-26 mm). RESULTS: Compared with the S-SE group, the L-SE group had a significantly longer mean interval between the last cesarean section and hospital admission (5.5 vs. 3.3 years; p < 0.01) and longer mean duration of symptoms before admission (43 vs. 17.4 months; p < 0.01). The L-SE group also had a significantly higher percentage of patients who had undergone at least one inconclusive diagnostic examination (Computed Tomography, Magnetic Resonance Imaging, fine needle biopsy, or laparoscopy) (39% vs. 0%; p < 0.05). As for US findings, L-SEs more frequently displayed cystic regions and fistulous tracts (p < 0.05), loss of round/oval shape (p < 0.05), and increased vascularity (p < 0.05). CONCLUSIONS: Delayed diagnosis of scar endometrioma reflected by a longer and more complex medical history results in larger than usual endometriomas with peculiar US findings, which are even more likely to be misinterpreted by physicians and radiologists.

10.
Acta Radiol ; 48(5): 514-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17520427

RESUMO

PURPOSE: To assess factors affecting the effectiveness of percutaneous laser ablation (PLA) under ultrasound (US) guidance in terms of complete ablation achievement. MATERIAL AND METHODS: The clinical records of 86 hepatocellular carcinoma (HCC) tumors (mean diameter 23.7 mm) in 60 cirrhotic patients (mean age 68.3 years; 36 males; 57 HCV+; 53 Child's class A, seven Child's class B) treated by means of PLA were reviewed. PLA was performed with a continuous-wave Nd:YAG laser by a single operator who positioned two to four 300-microm optic fibers advanced in 21-gauge needles into target lesions under US guidance. Triphasic computed tomography (CT) studies were used to verify treatment effectiveness 1 month after PLA completion. The association between characteristics of the lesion and outcome (complete or incomplete ablation) was evaluated by logistic regression, taking into account the following predictive factors: tumor size, pattern of growth (infiltrating or not) at imaging, location, first diagnosis of HCC (naïve tumors vs. non-naïve tumors), number of sessions (1/ > 1), total delivered energy, and years of treatment in 2001-2002 (first period) vs. 2003-2004 (second period). RESULTS: Complete ablation was obtained in 62 nodules (72%). Statistically significant predictors of incomplete ablation after the first PLA course at both univariate and multivariate analysis included: infiltrating growth pattern (odds ratio (OR) 12.3, P<0.002), non-naïve tumors (OR 8.7, P<0.001), and first period of treatment (OR 10.3, P<0.002). CONCLUSION: The effectiveness of US-guided PLA for HCC tumors < or =4 cm turned out to be negatively affected by both operator-related (the beginning of the operator's experience with the technique) and tumor-related factors (non-naïve, infiltrating HCC tumors).


Assuntos
Carcinoma Hepatocelular/cirurgia , Fotocoagulação a Laser/métodos , Cirrose Hepática/complicações , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/diagnóstico por imagem , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Necrose , Estudos Retrospectivos , Resultado do Tratamento , Ultrassonografia
11.
In Vivo ; 20(1): 187-91, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16433051

RESUMO

UNLABELLED: Tuberculosis (TB) is an important cause of morbidity and mortality worldwide. Here, we describe our experience of childhood tuberculous meningitis (TBM), focusing on factors influencing presentation and outcome. PATIENTS AND METHODS: Children aged 0-14 years, with diagnosis of TBM and 24 months of post-therapy follow-up, were evaluated in this retrospective study. RESULTS: Thirty-two patients with TBM were identified. Fever, nuchal rigidity and vomiting were the main presenting symptoms. Fourteen cases (44%) presented with cranial nerve palsy. Seventeen (53%) patients were in advanced stage of the disease on admission. Cerebrospinal fluid (CSF) examinations showed low glucose, high proteins and pleocytosis. A central nervous system device was placed in 4 cases (13%) because of worsening hydrocephalus. Four (13%) patients died, while 6 (19%) had sequelae. Faster normalization of CSF parameters was associated with better outcome. CONCLUSION: Early antimycobacterial therapy and close monitoring of TBM in childhood improve the outcome.


Assuntos
Tuberculose Meníngea/diagnóstico , Adolescente , Antituberculosos/administração & dosagem , Antituberculosos/uso terapêutico , Criança , Pré-Escolar , Quimioterapia Combinada , Humanos , Lactente , Recém-Nascido , Estudos Retrospectivos , Resultado do Tratamento , Tuberculose Meníngea/tratamento farmacológico , Tuberculose Meníngea/fisiopatologia
12.
Infection ; 32(3): 144-8, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15188073

RESUMO

BACKGROUND: Few data are available on histological features of chronic hepatitis B (HBV) and C (HCV) virus coinfection. PATIENTS AND METHODS: We enrolled 142 consecutive patients with viral chronic hepatitis on their first liver biopsy: 27 HBsAg and anti-HCV positive (case BC group), 57 HBsAg positive and anti-HCV negative (control B group) and 58 anti-HCV positive, HBsAg/anti-HBs/anti-HBc negative (control C group). RESULTS: Patients in the case BC group showed serum HBVDNA (37% vs 71.9%, p < 0.005) and ground-glass hepatocytes (37% vs 66.7%, p < 0.01) less frequently than those in the control B group. The case BC group showed a lower prevalence of patients with detectable HCV-RNA than the control C group (60% vs 92.3%, p < 0.001) and a significantly higher fibrosis score (2.1 +/- 1.2 vs 1.5 +/- 1.1, p < 0.05). Of the 27 patients in the case BC group, 10 lacked serum HCV-RNA and showed significantly higher histological activity index (HAI) and fibrosis scores than those found in the 17 HCV-RNA positive (8.5 +/- 4.4 vs 5.4 +/- 2.4 for HAI, p < 0.05; 3.0 +/- 1.3 vs 1.69 +/- 1.0, p < 0.05 for fibrosis). CONCLUSION: Liver histology seems to be more severe in chronic coinfection with HBV and HCV than in single infection, particularly when HCV replication is impaired.


Assuntos
Hepatite B Crônica/complicações , Hepatite B Crônica/patologia , Hepatite C Crônica/complicações , Hepatite C Crônica/patologia , Fígado/patologia , Adulto , DNA Viral/sangue , Feminino , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Humanos , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Índice de Gravidade de Doença
13.
J Chemother ; 16(6): 604-7, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15700855

RESUMO

UNLABELLED: Invasive aspergillosis is observed mainly in immunodepressed patients. Here we report a case of pulmonary aspergillosis with CNS involvement in a pregnant woman without other known causes of immunodeficiency. CASE REPORT: A 23-years old pregnant woman underwent a caesarean because of unexplained seizures. During the subsequent days worsening headache and a deteriorating neurological status were reported suggesting meningitis. Stiffness, right sided hemiparesis and cranial nerve palsies were observed at admission. Radiological findings revealed lesions involving the right pulmonary apex, the right cerebellar hemisphere and the Pterygopalatina fossa. Microbiological studies revealed large colonies of Aspergillus fumigatus. A favorable outcome was observed after administration of liposomal amphotericin B and 5-fluorocytosine and, at improved conditions, when oral uptake of itraconazole was given. The authors conclude that risk of infections sustained by fungal opportunistic agents during pregnancy must be considered. Sequential antifungal administration may be an efficient therapy able to shorten hospitalization.


Assuntos
Aspergilose Broncopulmonar Alérgica/complicações , Aspergillus fumigatus/patogenicidade , Abscesso Encefálico/microbiologia , Neuroaspergilose/etiologia , Complicações Infecciosas na Gravidez/microbiologia , Adulto , Antifúngicos/uso terapêutico , Aspergillus fumigatus/isolamento & purificação , Abscesso Encefálico/tratamento farmacológico , Cesárea , Feminino , Humanos , Neuroaspergilose/complicações , Neuroaspergilose/tratamento farmacológico , Gravidez , Complicações Infecciosas na Gravidez/patologia , Convulsões/etiologia , Convulsões/microbiologia , Resultado do Tratamento
14.
Environ Monit Assess ; 90(1-3): 121-33, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15887368

RESUMO

Brazil officially joined the International Long Term Ecological Research (ILTER) network in January 2000, when nine research sites were created and funded by the Brazilian Council for Science and Technology (CNPq). Two-years later some positive signs already emerge of the scientific, social and political achievements of the Brazilian LTER program. We discuss examples of how ecosystem and biodiversity information gathered within a long-term research approach are currently subsidizing decision-making as regards biodiversity conservation and watershed management at local and regional scales. Success in this respect has often been related to satisfactory communication between scientists, private companies, government and local citizens. Environmental education programs in the LTER sites are playing an important role in social and political integration. Most examples of integration of ecological research to decision-making in Brazil derive from case studies at local or regional scale. Despite the predominance of a bottom-up integrative pathway (from case studies to models; from local to national scale), some top-down initiatives are also in order, such as the construction of a model to estimate the inpact of different macroeconomic policies and growth trajectories on land use. We believe science and society in Brazil will benefit of the coexistence of bottom-up and top-down integrative approaches.


Assuntos
Biodiversidade , Tomada de Decisões , Ecossistema , Monitoramento Ambiental , Política Pública , Brasil , Análise Custo-Benefício , Exposição Ambiental/prevenção & controle , Saúde Ambiental , Geografia , Humanos , Gestão de Riscos
17.
Minerva Cardioangiol ; 49(5): 343-7, 2001 Oct.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-11533554

RESUMO

Coronary artery aneurysms involve the right coronary artery, the left anterior descending and the left circumflex coronary arteries in descending order of frequency; aneurysms involving the main left coronary artery are extremely rare. Atherosclerosis is the most common cause. Only eleven patients surgically treated with atherosclerotic left main coronary artery aneurysms are reported. We observed the twelfth case of atherosclerotic aneurysm of the left main coronary artery, successfully treated. In a 65-year-old man we found a large aneurysm originating at the distal segment of the left main coronary artery. A thromboendarterectomy was per-formed and was extended back into the left main and down the left anterior descending artery. An aneurysmorrhaphy and a three-vessel coronary artery bypass grafting were also performed. Three years later the patient was asymptomatic. Management of these cases is still controversial and based on anedoctal experience rather than controlled trials. Although surgery has been recommended to prevent complications, there are no available data comparing medical and surgical management. We feel that coronary bypasses should be performed in coronary artery aneurysm patients only when indicated by the severity of stenosis or progressive angina despite medical therapy. It is our opinion that anurysmorraphy should preserve native flow as much as possible.


Assuntos
Aneurisma Coronário/complicações , Doença da Artéria Coronariana/complicações , Idoso , Humanos , Masculino
18.
J Neurovirol ; 7(3): 196-207, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11517394

RESUMO

HIV dementia (HIVD), a disease that is apparently mediated by neurotoxins and viral proteins secreted by HIV infected microglia, is characterized neuropathologically by an increased number of activated microglia in the brains of affected individuals. Consequently, the rational design of potential therapeutic strategies should take into account the mechanisms that lead to microglial activation and to their increased prominence in the adult brain. In this regard, one leading hypothesis proposes that microglia are recruited to specific sites in the central nervous system (CNS) as a result of interactions between microglial chemokine receptors and chemokines, or even the viral glycoprotein gp120, which binds chemokine receptors in the process of cellular entry. Adult microglia express the functional chemokine receptors CCR5 and CXCR4 molecules that mediate chemotaxis in these and other cell types. We determined that purified adult microglial cultures contain a heterogeneous population with respect to their ability to respond to the alpha- and beta-chemokines, SDF1alpha, and MIP-1beta. A mean of 14.6% of the microglia assayed responded to both alpha- and beta-chemokines (CCR5(+)CXCR4(+) phenotype); 45.4% of microglia were phenotyped as CCR5(+)CXCR4(-); 12.9% of the microglia were CXCR4(+)CCR5(-); and 27.0% of microglia did not respond to either chemokine. No increase in intracellular calcium levels was seen in the vast majority of microglia exposed to the soluble HIV envelope protein, gp120, or to HIV envelope (gp120/gp41) expressed on MLV virus pseudotypes. However, exposure of microglia to soluble fractalkine or to other chemokines resulted in an intracellular calcium flux. Our results raise the possibility of microglial heterogeneity with respect to their response to chemokines, and indicate that any effects due to gp120 are likely to be considerably less robust than the response of microglia to the natural ligands of their chemokine receptors, for example SDF1alpha and MIP-1beta.


Assuntos
Complexo AIDS Demência/virologia , Quimiocinas CXC/imunologia , Proteína gp120 do Envelope de HIV/imunologia , HIV-1 , Proteínas Inflamatórias de Macrófagos/imunologia , Microglia/virologia , Complexo AIDS Demência/imunologia , Adulto , Cálcio/metabolismo , Sinalização do Cálcio/imunologia , Células Cultivadas , Quimiocina CCL4 , Quimiocina CXCL12 , Quimiocinas CXC/metabolismo , Proteína gp120 do Envelope de HIV/metabolismo , Humanos , Imunofenotipagem , Proteínas Inflamatórias de Macrófagos/metabolismo , Microglia/química , Microglia/citologia , Receptores CCR5/análise , Receptores CXCR4/análise , Lobo Temporal/citologia
19.
Neuropathol Appl Neurobiol ; 27(2): 127-38, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11437993

RESUMO

The CXCR3 chemokine receptor, expressed on activated T lymphocytes, is seen within the central nervous system (CNS) in inflammatory conditions where a T-cell response is prominent. However, the distribution of CXCR3 in parenchymal CNS cells is unknown. Using a monoclonal antibody against CXCR3 and post-mortem tissue of patients with and without CNS pathology, we have determined its expression pattern. CXCR3 was found in subpopulations of cells morphologically consistent with astrocytes, particularly reactive astrocytes, and in cerebellar Purkinje cells. It was also detected in arterial endothelial and smooth muscle cells, particularly in areas associated with atherosclerotic plaques. CXCR3-positive astrocytes were particularly prominent in the CNS of HIV-positive patients, in patients with Multiple Sclerosis (MS), in ischaemic infarcts and in astrocytic neoplasms. Immunofluorescence studies of mixed adult primary glial cultures and fetal glial cultures also showed expression of CXCR3 in astrocytes. CXCR3 mRNA was detected in Purkinje cells by in situ hybridization with a CXCR3-specific probe. Thus, the predominant expression of CXCR3 in reactive astrocytes may indicate that it plays a role in the development of reactive gliosis in a variety of infectious, inflammatory, vascular and neoplastic processes in the CNS. The relationship between CXCR3 expression in astrocytes to its expression in Purkinje cells, endothelial cells and smooth muscle cells is yet to be determined.


Assuntos
Encefalopatias/fisiopatologia , Receptores de Quimiocinas/genética , Complexo AIDS Demência/patologia , Complexo AIDS Demência/fisiopatologia , Adulto , Idoso , Astrócitos/citologia , Encefalopatias/patologia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/fisiopatologia , Capilares/química , Capilares/fisiologia , Células Cultivadas , Artérias Cerebrais/química , Artérias Cerebrais/fisiologia , Veias Cerebrais/química , Veias Cerebrais/fisiologia , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/patologia , Esclerose Múltipla/fisiopatologia , Células de Purkinje/química , Células de Purkinje/fisiologia , RNA Mensageiro/análise , Receptores CXCR3 , Receptores de Quimiocinas/análise , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/fisiopatologia , Lobo Temporal/citologia
20.
J Peripher Nerv Syst ; 6(1): 2-7, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11293803

RESUMO

The role of the human immunodeficiency virus (HIV) and other viruses in the development of neuropathies associated with HIV infection is controversial. Distal symmetric polyneuropathy (DSP), the most common subtype of HIV-associated neuropathy, is characterized by an abundance of reactive macrophages within the peripheral nerve, but HIV replication is limited to a small percentage of the macrophages. Thus, the pathological destruction may be mediated by pro-inflammatory signals amplified by activated glial elements within the nerve, similar to the proposed mechanism of damage caused by HIV within the central nervous system. In contrast, in mononeuropathy multiplex (MM) and progressive polyneuropathy (PP), cytomegalovirus (CMV) replication in the peripheral nerve is consistently demonstrable, and this replication likely results in direct damage to the infected cells (neurons and glia). The rarest form of HIV-associated neuropathy, the diffuse infiltrative lymphocytosis syndrome (DILS), is characterized by an intense CD8+ T lymphocyte infiltration into the nerve and abundant HIV infection of macrophages. Finally, while other viruses (varicella zoster, herpes simplex) are associated with myelitis in HIV-infected individuals, there is little support for a role for these viruses in HIV-associated neuropathy.


Assuntos
Infecções por Citomegalovirus/complicações , Citomegalovirus , Infecções por HIV/complicações , HIV-1 , Polineuropatias/virologia , Humanos
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