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1.
BMC Microbiol ; 21(1): 341, 2021 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-34903172

RESUMO

BACKGROUND: Fungal infections impact over 25% of the global population. For the opportunistic fungal pathogen, Cryptococcus neoformans, infection leads to cryptococcosis. In the presence of the host, disease is enabled by elaboration of sophisticated virulence determinants, including polysaccharide capsule, melanin, thermotolerance, and extracellular enzymes. Conversely, the host protects itself from fungal invasion by regulating and sequestering transition metals (e.g., iron, zinc, copper) important for microbial growth and survival. RESULTS: Here, we explore the intricate relationship between zinc availability and fungal virulence via mass spectrometry-based quantitative proteomics. We observe a core proteome along with a distinct zinc-regulated protein-level signature demonstrating a shift away from transport and ion binding under zinc-replete conditions towards transcription and metal acquisition under zinc-limited conditions. In addition, we revealed a novel connection among zinc availability, thermotolerance, as well as capsule and melanin production through the detection of a Wos2 ortholog in the secretome under replete conditions. CONCLUSIONS: Overall, we provide new biological insight into cellular remodeling at the protein level of C. neoformans under regulated zinc conditions and uncover a novel connection between zinc homeostasis and fungal virulence determinants.


Assuntos
Cryptococcus neoformans/patogenicidade , Chaperonas Moleculares/metabolismo , Proteoma/metabolismo , Secretoma/metabolismo , Zinco/metabolismo , Cryptococcus neoformans/metabolismo , Cápsulas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Melaninas/metabolismo , Chaperonas Moleculares/genética , Mutação , Proteômica , Termotolerância , Virulência/genética
2.
Sci Rep ; 10(1): 951, 2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31969642

RESUMO

Olfactory ensheathing cells (OECs) are crucial for promoting the regeneration of the primary olfactory nervous system that occurs throughout life. Transplantation of OECs has emerged as a promising therapy for nervous system injuries, in particular for spinal cord injury repair. Functional outcomes in both animals and humans are, however, highly variable, primarily because it is difficult to rapidly obtain enough OECs for transplantation. Compounds which can stimulate OEC proliferation without changing the phenotype of the cells are therefore highly sought after. Additionally, compounds which can stimulate favourable cell behaviours such as migration and phagocytic activity are desirable. We conducted a medium-throughput screen testing the Davis open access natural product-based library (472 compounds) and subsequently identified the known plant natural product 2-methoxy-1,4-naphthoquinone as a stimulant of OEC viability. We showed that 2-methoxy-1,4-naphthoquinone: (i) strongly stimulates proliferation over several weeks in culture whilst maintaining the OEC phenotype; (ii) stimulates the phagocytic activity of OECs, and (iii) modulates the cell cycle. We also identified the transcription factor Nrf2 as the compound's potential molecular target. From these extensive investigations we conclude that 2-methoxy-1,4-naphthoquinone may enhance the therapeutic potential of OECs by stimulating proliferation prior to transplantation.


Assuntos
Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Naftoquinonas/farmacologia , Bulbo Olfatório/citologia , Fagocitose/efeitos dos fármacos , Animais , Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Transplante de Células , Células Cultivadas , Eremophila (Planta)/química , Ensaios de Triagem em Larga Escala/métodos , Humanos , Camundongos , Fator 2 Relacionado a NF-E2 , Naftoquinonas/isolamento & purificação , Traumatismos da Medula Espinal , Regeneração da Medula Espinal
3.
Clin Neurol Neurosurg ; 123: 155-63, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24956545

RESUMO

Refractory pain syndromes often have far reaching effects and are quite a challenge for primary care providers and specialists alike to treat. With the help of site-specific neuromodulation and appropriate patient selection these difficult to treat pain syndromes may be managed. In this article, we focus on supraspinal stimulation (SSS) for treatment of intractable pain and discuss off-label uses of deep brain stimulation (DBS) and motor cortex stimulation (MCS) in context to emerging indications in neuromodulation. Consideration for neuromodulatory treatment begins with rigorous patient selection based on exhaustive conservative management, elimination of secondary gains, and a proper psychology evaluation. Trial stimulation prior to DBS is nearly always performed while trial stimulation prior to MCS surgery is symptom dependent. Overall, a review of the literature demonstrates that DBS should be considered for refractory conditions including nociceptive/neuropathic pain, phantom limb pain, and chronic cluster headache (CCH). MCS should be considered primarily for trigeminal neuropathic pain (TNP) and central pain. DBS outcome studies for post-stroke pain as well as MCS studies for complex regional pain syndrome (CRPS) show more modest results and are also discussed in detail.


Assuntos
Estimulação Encefálica Profunda , Córtex Motor/fisiopatologia , Neuralgia/terapia , Dor Intratável/terapia , Ensaios Clínicos como Assunto , Estimulação Encefálica Profunda/métodos , Humanos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/fisiopatologia
4.
Eur J Pain ; 16(10): 1414-25, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22556099

RESUMO

BACKGROUND: Neuropathy can lead not only to impaired function but also to sensory sensitization. We aimed to link reduced skin nerve fibre density in different levels to layer-specific functional impairment in neuropathic pain patients and tried to identify pain-specific functional and structural markers. METHODS: In 12 healthy controls and 36 patients with neuropathic pain, we assessed clinical characteristics, thermal thresholds (quantitative sensory testing) and electrically induced pain and axon reflex erythema. At the most painful sites and at intra-individual control sites, skin biopsies were taken and innervation densities in the different skin layers were assessed. Moreover, neuronal calcitonin gene-related peptide staining was quantified. RESULTS: Perception of warm, cold and heat pain and nerve fibre density were reduced in the painful areas compared with the control sites and with healthy controls. Warm and cold detection thresholds correlated best with epidermal innervation density, whereas heat and cold pain thresholds and axon reflex flare correlated best with dermal innervation density. Clinical pain ratings correlated only with epidermal nerve fibre density (r = 0.38, p < 0.05) and better preserved cold detection thresholds (r = 0.39, p < 0.05), but not with other assessed functional and structural parameters. CONCLUSIONS: Thermal thresholds, axon reflex measurements and assessment of skin innervation density are valuable tools to characterize and quantify peripheral neuropathy and link neuronal function to different layers of the skin. The severity of small fibre neuropathy, however, did not correspond to clinical pain intensity and a specific parameter or pattern that would predict pain intensity in peripheral neuropathy could not be identified.


Assuntos
Fibras Nervosas/patologia , Neuralgia/patologia , Pele , Adulto , Estudos de Casos e Controles , Temperatura Baixa , Derme/inervação , Derme/patologia , Epiderme/inervação , Epiderme/patologia , Feminino , Temperatura Alta , Humanos , Hiperalgesia/patologia , Masculino , Pessoa de Meia-Idade , Limiar da Dor , Limiar Sensorial , Pele/inervação , Pele/patologia , Tato
5.
Eye (Lond) ; 18(8): 809-13, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-14963483

RESUMO

AIMS: To report on the clinical efficacy of verteporfin photodynamic therapy (PDT) in the treatment of choroidal neovascularisation (CNV) in an NHS setting and to compare treatment rates and outcomes with those in the published literature. PATIENTS AND METHODS: Patients with a visual acuity of 6/60 or better Snellen equivalent and predominantly classic or classic/no occult CNV within 200 microm of the centre of the fovea were enrolled and followed for a minimum of 12 months. Assessment at baseline and all follow-up visits comprised refraction protocol logMAR visual acuity, contrast sensitivity, and stereoscopic fluorescein angiography. RESULTS: A total of 170 eyes of 159 patients were enrolled with CNV due to: 147 age-related macular degeneration (AMD) (90 classic/no occult, 21 recurrent after confluent laser, 36 predominantly classic with occult), 10 pathological myopia, and 13 others. Response to treatment (loss of < 15 letters) at 12 months was 73% overall, 76% in AMD, 70% in classic/no occult, and 89% in predominantly classic. The mean number of treatments in the first year was 2.7. Contrast sensitivity was unchanged. CONCLUSIONS: Verteporfin PDT delivered in a NHS setting can be at least as effective as and requires fewer treatments than reported in the literature.


Assuntos
Neovascularização de Coroide/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/uso terapêutico , Neovascularização de Coroide/etiologia , Neovascularização de Coroide/fisiopatologia , Sensibilidades de Contraste , Seguimentos , Humanos , Degeneração Macular/complicações , Miopia/complicações , Recidiva , Verteporfina , Acuidade Visual
6.
J Cyst Fibros ; 2(4): 206-13, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15463875

RESUMO

BACKGROUND: Disease progression in cystic fibrosis (CF) is marked by deterioration across a number of physiological systems. In addition, there is evidence that females have a worse prognosis than males. The current work assesses the impact of both these factors on health related quality of life (HRQoL). METHODS: Two hundred and twenty-three adolescents and adults completed the cystic fibrosis quality of life (CFQoL) questionnaire with a further 185 approached and not responding by non-completion of the questionnaire. The CFQoL is divided into nine domains: physical, social, treatment, chest symptoms, emotional functioning, concerns for the future, relationships, body image, and career. Measurement of objective clinical status included, body mass index (BMI), and percentage of predicted forced expiratory volume in one second (FEV1). General health perceptions (GHP) were also measured. RESULTS: Patients were sub-divided by gender and disease severity (mild > 70% FEV1, moderate 40-69% and severe < 40%). Factorial analysis of variance indicated significant main effects for FEV1 (F = 587.98, P < or = 0.001) and BMI (F = 17.29, P < or = 0.001) as a function of disease severity. Post hoc tests revealed significant two-group differences for FEV1 and BMI between disease severity groups. No differences were observed for gender across FEV1 or BMI. Differences emerged across most CFQoL domains for disease severity, with the exception of concerns for the future, which was consistently low throughout. Gender differences emerged for chest symptoms, emotional functioning, concerns for the future, body image and career. With the exception of body image, females exhibited poorer HRQoL. Pearson correlations indicated that females' perception of health was more closely related to clinical status than males. CONCLUSIONS: Disease severity has an impact on HRQoL in adolescents and adults with CF. Some differences emerged between males and females, with females generally reporting poorer HRQoL. Evidence indicated that males and females perceived their health status differently, with females having a more accurate perception of objective clinical health status.


Assuntos
Atitude Frente a Saúde , Fibrose Cística/psicologia , Qualidade de Vida , Adaptação Psicológica , Adolescente , Adulto , Fatores Etários , Estudos Transversais , Fibrose Cística/diagnóstico , Fibrose Cística/terapia , Feminino , Seguimentos , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Percepção , Probabilidade , Testes de Função Respiratória , Medição de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Perfil de Impacto da Doença , Inquéritos e Questionários , Reino Unido
7.
J Cyst Fibros ; 1(3): 137-45, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15463820

RESUMO

BACKGROUND: Generic health-related quality of life measures are often applied to disease groups without assessment of their psychometric properties. The current work assesses the properties of the Short Form 36-item (SF-36) questionnaire in a British sample of adolescents and adults with cystic fibrosis (CF). METHODS: Two hundred and twenty-three adolescents and adults with CF completed the SF-36 with a further 185 approached and not responding by non-completion of the questionnaire. The structure and internal reliability of the instrument was assessed by principal components analysis, Cronbach alpha coefficients and item to domain correlations. Differences between disease severity groups were assessed by analysis of variance. RESULTS: Factor analysis of the SF-36 scores broadly confirmed domain structures for the SF-36. Cronbach alpha coefficients were high (range 0.82-0.91) and item-to-same domain correlations were stronger than item-to-unrelated domain correlations. Examination of differences between mild, moderate and severe disease states revealed four significant main effects for: physical functioning, role limitation due to physical functioning, general health perceptions and energy and vitality. The analysis also revealed the presence of numerous ceiling effects across domains. CONCLUSIONS: The domain structure of the SF-36 was demonstrated to be robust. However, the discriminatory ability of the measure was disappointing. The presence of ceiling effects and the low frequency of differences between intermediate disease severity groups indicated that the SF-36 was not discriminatory with respect to mild disease states or progression of illness.


Assuntos
Fibrose Cística , Indicadores Básicos de Saúde , Qualidade de Vida , Inquéritos e Questionários , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Fatores Sexuais
8.
J Acquir Immune Defic Syndr ; 28(3): 264-9, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11694834

RESUMO

OBJECTIVES: To determine trends in HIV infection and risk behaviors among street-recruited self-identified gay and bisexual male injection drug users (IDUs) in San Francisco. METHODS: Trends in HIV infection and risk behaviors were calculated for gay/bisexual ( n = 1594 interviews) IDUs in 26 semiannual cross sections from 1988 to 2000. RESULTS: HIV seroprevalence among gay/bisexual IDUs decreased from the range of 35% to 45% in 1988/1989 to 25% in 1996 and then began to increase, reaching 42% in 2000. In contrast, HIV prevalence among heterosexual male IDUs remained stable during the study period. For gay/bisexual IDUs, injection and sex-related HIV risk behaviors declined modestly throughout the study period. As of the last cross section (July 2000), however, over a third of respondents reported recent syringe sharing or unprotected anal sex. CONCLUSIONS: Gay/bisexual men who inject drugs continue to be at elevated risk for HIV, suggesting that interventions such as amphetamine drug treatment and sexual risk reduction programs targeted at this population are needed.


Assuntos
Infecções por HIV/epidemiologia , HIV/imunologia , Abuso de Substâncias por Via Intravenosa/virologia , HIV/classificação , Infecções por HIV/etiologia , Infecções por HIV/virologia , Heterossexualidade , Homossexualidade Masculina , Humanos , Masculino , Assunção de Riscos , São Francisco/epidemiologia , Estudos Soroepidemiológicos , Abuso de Substâncias por Via Intravenosa/complicações
9.
Am J Public Health ; 91(11): 1842-6, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11684613

RESUMO

OBJECTIVES: This study sought to determine prevalence of and risk factors for nonfatal recent overdose among street-recruited injection heroin users. METHODS: From August 1998 through July 1999, 1427 heroin injectors were recruited from 6 inner-city neighborhoods in the San Francisco Bay Area, Calif, and interviewed. Factors hypothesized to be associated with recent overdose were analyzed with logistic regression. RESULTS: Of the 1427 participants, 684 (48%) had had an overdose, 466 (33%) had experienced 2 or more overdose events, and 182 (13%) had had a recent overdose. In multiple logistic regression, being younger (adjusted odds ratio [OR] for each year of increasing age = 0.95; 95% confidence interval [CI] = 0.94, 0.97), having been arrested 3 or more times in the past year (adjusted OR = 2.50; 95% CI = 1.61, 3.87), drinking 4 or more alcoholic drinks per day (adjusted OR = 2.05; 95% CI = 1.37, 3.05), and having participated in methadone detoxification during the past year (adjusted OR = 1.47; 95% CI = 1.03, 2.09) were independently associated with recent overdose. Being homeless; identifying as gay, lesbian, bisexual, or transgender; having spent 5 or more years in prison or jail; and having engaged in sex work also were associated with recent overdose. CONCLUSIONS: Targeted interventions that decrease risk for overdose are urgently needed.


Assuntos
Overdose de Drogas/epidemiologia , Heroína/efeitos adversos , Abuso de Substâncias por Via Intravenosa/complicações , Adulto , Feminino , Comportamentos Relacionados com a Saúde , Educação em Saúde , Heroína/administração & dosagem , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , São Francisco/epidemiologia , Abuso de Substâncias por Via Intravenosa/epidemiologia , Saúde da População Urbana
10.
J Interferon Cytokine Res ; 21(3): 181-5, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11331041

RESUMO

Serum levels of matrix metalloprotease-9 (MMP-9) and tissue inhibitor of MMP-1 (TIMP-1) were measured monthly in 7 patients with relapsing-remitting multiple sclerosis (MS) 6 months before and 6 months during treatment with weekly intramuscular (i.m.) injections of interferon-beta1a (IFN-beta1a) 30 microg. Within-patient median MMP-9 levels were unchanged on treatment. Within-patient median TIMP-1 levels were higher during months 1-6 (771.5 ng/ml) and during months 4, 5, and 6 of treatment (793 ng/ml) compared with 6 months pretreatment (414 ng/ml) (respectively, p = 0.10, p = 0.047; Wilcoxon signed-rank test). These preliminary data suggest that IFN-beta1a therapy may increase TIMP-1 levels.


Assuntos
Interferon beta/farmacologia , Esclerose Múltipla Recidivante-Remitente/sangue , Inibidor Tecidual de Metaloproteinase-1/sangue , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Injeções Intramusculares , Interferon beta-1a , Interferon beta/administração & dosagem , Interferon beta/uso terapêutico , Imageamento por Ressonância Magnética , Masculino , Metaloproteinase 9 da Matriz/sangue , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/enzimologia , Esclerose Múltipla Recidivante-Remitente/metabolismo , Fatores de Tempo
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