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1.
Int J Mol Sci ; 23(3)2022 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-35163248

RESUMEN

Gram-negative sepsis driven by lipopolysaccharide (LPS) has detrimental outcomes, especially in neonates. The neutrophil-derived bactericidal/permeability-increasing protein (BPI) potently neutralizes LPS. Interestingly, polymorphism of the BPI gene at position 645 (rs4358188) corresponds to a favorable survival rate of these patients in the presence of at least one allele 645 A as opposed to 645 G. When we exploited the existing X-ray crystal structure, the corresponding amino acid at position 216 was revealed as surface exposed and proximal to the lipid-binding pocket in the N-terminal domain of BPI. Our further analysis predicted a shift in surface electrostatics by a positively charged lysine (BPI216K) exchanging a negatively charged glutamic acid (BPI216E). To investigate differences in interaction with LPS, we expressed both BPI variants recombinantly. The amino acid exchange neither affected affinity towards LPS nor altered bactericidal activity. However, when stimulating human peripheral blood mononuclear cells, BPI216K exhibited a superior LPS-neutralizing capacity (IC50 12.0 ± 2.5 pM) as compared to BPI216E (IC50 152.9 ± 113.4 pM, p = 0.0081) in respect to IL-6 secretion. In conclusion, we provide a functional correlate to a favorable outcome of sepsis in the presence of BPI216K.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/genética , Péptidos Catiónicos Antimicrobianos/metabolismo , Proteínas Sanguíneas/genética , Proteínas Sanguíneas/metabolismo , Lipopolisacáridos/metabolismo , Polimorfismo Genético/genética , Alelos , Secuencia de Aminoácidos , Aminoácidos/genética , Aminoácidos/metabolismo , Animales , Células Cultivadas , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Leucocitos Mononucleares/metabolismo , Ratones , Neutrófilos/metabolismo
2.
Int J Mol Sci ; 21(5)2020 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-32150869

RESUMEN

Patients with pancreatic ductal adenocarcinoma (PDAC) normally have a poor long-term prognosis. However, some rare cases of long-term survivors have been reported. The tumor microenvironment, consisting of cellular and stromal components, possibly plays an important role and might influence prognosis. In this context, the role of tumor-infiltrating B-cells and its impact on the survival in patients with PDAC remains controversial. We therefore aimed to assess the prognostic value of CD20-positive B-cells and CD20-positive B-cell aggregates as well as CD138, IgM, Pax5, and Ki67 on the survival of patients with PDAC using immunohistochemistry of FFPE pancreatectomy tissue sections from patients that underwent primary surgery for pT3- and R0-pancreatic adenocarcinoma between 1995 and 2016. Patients with PDAC were matched and grouped in 16 long-term-survivors (LTS, median overall survival (OS): 96 months [range: 61-177 months]) and 16 short-term-survivors (STS, median OS: 16 months [range: 7-32 months]). CD20-positive B-cells and B-cell aggregates in the tumor infiltration zone were significantly upregulated in the LTS-group compared to the STS-group (p = 0.0499 respectively p = 0.0432). Regarding the entire patient cohort (n = 32) CD20 positive B-cell aggregates in the tumor infiltration zone were an independent prognostic marker for overall survival in multivariate analysis (HR 9.2, CI 1.6-51.4, p = 0.012). These results underline the importance of tumor-associated B-cells for prognosis of patients with PDAC. The detailed role of B cells in the pathomechanism of PDAC should be further investigated for predicting outcome, identifying appropriate treatment regimens, and developing novel therapeutic options.


Asunto(s)
Antígenos CD20/metabolismo , Linfocitos B/inmunología , Carcinoma Ductal Pancreático/mortalidad , Linfocitos Infiltrantes de Tumor/inmunología , Pancreatectomía/mortalidad , Neoplasias Pancreáticas/mortalidad , Microambiente Tumoral/inmunología , Anciano , Carcinoma Ductal Pancreático/inmunología , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/cirugía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/inmunología , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Pronóstico , Tasa de Supervivencia
3.
Int J Prison Health (2024) ; 20(1): 30-46, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38984552

RESUMEN

PURPOSE: Prisonersare at disproportionate risk of suffering substance-related harms. The administration of naloxone is essential to reversing opioid overdose and minimizing substance-related harms in prison and the community. The purpose of this study is to examine how naloxone administration is practiced and perceived in prison settings. DESIGN/METHODOLOGY/APPROACH: The authors conducted surveys with correctional workers in Manitoba, Canada (n = 257) to examine how they understand and feel about the need for and practice of administering naloxone in their everyday work with criminalized populations. FINDINGS: Respondents reported feeling a great need to administer naloxone, but most did not feel adequately trained to administer naloxone, creating the perception that criminalized populations remain at enhanced risk. ORIGINALITY/VALUE: Findings provide emerging evidence of the need for training and accompanying policies and procedures for correctional workers on how to access and administer naloxone.


Asunto(s)
Naloxona , Antagonistas de Narcóticos , Naloxona/uso terapéutico , Naloxona/administración & dosificación , Humanos , Antagonistas de Narcóticos/uso terapéutico , Antagonistas de Narcóticos/administración & dosificación , Masculino , Femenino , Manitoba , Adulto , Prisiones , Persona de Mediana Edad , Sobredosis de Droga/tratamiento farmacológico , Sobredosis de Droga/prevención & control , Sobredosis de Droga/epidemiología , Personal de Instituciones Correccionales
4.
Int J Drug Policy ; 111: 103934, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36549200

RESUMEN

BACKGROUND AND AIMS: Shifting political contexts can significantly alter drug policy approaches and available supports for People Who Use Drugs (PWUD). The purpose of this study was to explore how shifts in provincial drug policy approaches, specifically the replacement of a Safe Consumption Site (SCS) with a smaller mobile Overdose Prevention Site (OPS) in Lethbridge, Alberta Canada, impacted PWUD' access to and experiences with harm reduction services. METHODS: We conducted semi-structured interviews with 50 PWUD in the City of Lethbridge, Canada. Through traditional fieldwork, we recruited participants within, and just outside of, downtown Lethbridge. Using a standardized general prompt guide to begin interviews, participants were asked a variety of questions about their experiences with and perceptions of SCS access and changes to SCS provisions. Interviews were audio recorded, then transcribed, coded, and analyzed. RESULTS: Participants reported regular and frequent access and overall positive experiences with the SCS, despite also noting certain operational barriers (e.g., long wait times). By contrast, participants reported more limited use of the new OPS compared to the SCS because of three main reasons: (1) concerns about location; (2) smoking room elimination; and (3) lack of social space and activities. Overall, changes to SCS provision produced a range of negative consequences for PWUD in Lethbridge. These relate to perceived increases in drug-related harms (e.g., increased overdoses) as well as negative social impacts (e.g., lack of place to meet other people). CONCLUSION: Findings from this study provide preliminary indications of the importance of understanding how contextual and locally-specific elements (location, limits on permitted route administration, and social aspects) can work together to facilitate SCS uptake and even overcome traditional SCS barriers. Conversely, the absence of such elements can hinder SCS uptake. Results show that the value of SCS might differ across locations, pointing to the need for further locally-grounded examinations of harm reduction service uptake and experience.


Asunto(s)
Sobredosis de Droga , Humanos , Canadá , Sobredosis de Droga/prevención & control , Ciudades , Reducción del Daño , Políticas
5.
Int J Offender Ther Comp Criminol ; 67(16): 1699-1721, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-36597277

RESUMEN

Internationally, parole work is loaded with tensions, particularly when supervising a people convicted of sex crimes (PCSCs) who, due to their criminal history, are stigmatized and occupy the lowest rungs of the status hierarchy in prison and society more broadly. Drawing on analyses of interview data from federal parole officers (n = 150) employed by Correctional Service Canada, we interpret their perceptions and feelings about overseeing re-entry preparations and processes for the PCSCs on their caseloads. We unpack the "tensions" imbued in parole officers' internal reflections and negotiation of complexities in their efforts toward supporting client's rehabilitation efforts, desistance from crime while negotiating external factors (e.g., the lack of available programming), and being responsible for supervising PCSCs. We highlight facets of occupational stress parole officers experience, finding PCSCs may be more compliant when under supervision but may also require more of a parole officer's resources, including time and energy. We put forth recommendations for greater empirical nuance concerning parole officer work and their occupational experiences and beliefs about PCSC, particularly as related to parole officer health.


Asunto(s)
Criminales , Estrés Laboral , Prisioneros , Humanos , Crimen , Emociones
6.
J Orthop Surg Res ; 18(1): 893, 2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-37993946

RESUMEN

BACKGROUND: Short stems were introduced into total hip arthroplasty (THA) to preserve bone stock, to transmit more load to the proximal femur, and to enable minimal invasive approaches. This study is the first long-term study (with a follow-up of 10 years) of the survival as well as the clinical and radiographic outcomes of the Fitmore hip stem, a short curved uncemented stem. METHODS: In total, 123 Fitmore hip stems were prospectively evaluated. At the final 10-year follow-up, 80 Fitmore stems (78 patients: 30 female, 48 male) were eligible for evaluation. Clinical parameters were thigh pain, EQ-5D, Harris Hip Score (HHS) and Oxford Hip Score. Radiographic parameters were cortical hypertrophy (CH), bone condensation, cortical thinning, radiolucency, reactive lines, calcar rounding, calcar resorption, subsidence and varus/valgus position. RESULTS: After 10 years, there was a survival rate of 99% (1 revision because of aseptic stem loosening). HHS had improved from 59 to 94 and Oxford Hip Score from 22 to 43. CH rate after 1 year was 69% and after 10 years 74%. In the first year, radiolucency was found in 58% and in 17.5% after 10 years. Subsidence after 1 year was 1.6 ± 1.6 mm and 5.0 ± 3.1 mm after 10 years. CONCLUSIONS: The Fitmore hip stem showed a survival rate of 99% as well as good clinical and radiographic outcomes in the long-term follow-up of 10 years.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Humanos , Masculino , Femenino , Artroplastia de Reemplazo de Cadera/métodos , Hipertrofia , Fémur/cirugía , Huesos/cirugía , Diseño de Prótesis , Estudios de Seguimiento , Resultado del Tratamiento
7.
BMJ Open ; 13(8): e067813, 2023 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-37532474

RESUMEN

INTRODUCTION: In Manitoba, Canada, there has been an increase in the number of people newly diagnosed with HIV and those not returning for regular HIV care. The COVID-19 pandemic resulted in increased sex and gender disparities in disease risk and mortalities, decreased harm reduction services and reduced access to healthcare. These health crises intersect with increased drug use and drug poisoning deaths, houselessness and other structural and social factors most acutely among historically underserved groups. We aim to explore the social and structural barriers and facilitators to HIV care and harm reduction services experienced by people living with HIV (PLHIV) in Manitoba. METHODS AND ANALYSIS: Our study draws on participatory action research design. Guiding the methodological design are the lived experiences of PLHIV. In-depth semi-structured face-to-face interviews and quantitative questionnaires will be conducted with two groups: (1) persons aged ≥18 years living or newly diagnosed with HIV and (2) service providers who work with PLHIV. Data collection will include sex, gender, sociodemographic information, income and housing, experiences with the criminal justice system, sexual practices, substance use practices and harm reduction access, experiences with violence and support, HIV care journey (since diagnosis until present), childhood trauma and a decision-making questionnaire. Data will be analysed intersectionally, employing grounded theory for thematic analysis, sex-based and gender-based analysis and social determinants of health and syndemic framework to understand the experiences of PLHIV in Manitoba. ETHICS AND DISSEMINATION: We received approval from the University of Manitoba Health Ethics Research Board (HS25572; H2022:218), First Nations Health and Social Secretariat of Manitoba, Nine Circles Community Health Centre, Shared Health Manitoba (SH2022:194) and 7th Street Health Access Centre. Findings will be disseminated using community-focused knowledge translation strategies identified by participants, peers, community members and organisations, and reported in conferences, peer-reviewed journals and a website (www.alltogether4ideas.org).


Asunto(s)
COVID-19 , Infecciones por VIH , Trastornos Relacionados con Sustancias , Masculino , Femenino , Humanos , Adolescente , Adulto , Manitoba/epidemiología , Reducción del Daño , Sindémico , Pandemias , Trastornos Relacionados con Sustancias/epidemiología , Trastornos Relacionados con Sustancias/terapia , Atención a la Salud , Infecciones por VIH/epidemiología , Infecciones por VIH/terapia
8.
Criminol Crim Justice ; 22(5): 774-789, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36211631

RESUMEN

Drawing on interview data with over 50 male former prisoners in Ontario, Canada, we examine male ex-prisoners' narratives of change within prison settings. Specifically, we focus on how ex-prisoners talk about change to self and their persona, as they reflect back on both their pre-prison selves and the ways they believe prison changed them. We find that these ex-prisoners described prison as a time where they developed a more general sense of positive change. Ex-prisoners described how prison living made them "calmer," "stronger," and more "patient" overall. These descriptions stand in tension with the overall hostility of prison environments where prisoners are forced to focus on survival and basic well-being as they navigate the risks and threats of prison living. Overall, in this article, we seek to contribute to emerging discussions on positivity within prison settings, acknowledging that studying the more positive impacts of prison is a delicate yet important endeavor necessary to help better understand the experiential complexities of punishment.

9.
Int J Drug Policy ; 104: 103671, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35413583

RESUMEN

BACKGROUND: Police presence near Supervised Consumption Services (SCS) and other harm reduction services has been shown to hamper access to these critical facilities for People Who Use Drugs (PWUD). However, few studies document the empirical nuances of these contextually dependant police-PWUD relationships, and how PWUD' experiences and perceptions of policing near harm reduction services shape SCS access. If the goal is to increase SCS uptake, understanding the complexities of PWUD-police relations near SCS is imperative for guiding both formal policy and informal best-practices. METHODS: We report findings from a larger qualitative study on PWUD' experiences with SCS in two Canadian cities. Data were collected through 75 face-to-face interviews and observations with street-involved PWUD near local SCS in Edmonton and Calgary, Alberta. RESULTS: Participants' perceptions of and experiences with policing varied across jurisdictions. Participants in Calgary reported concentrated police presence in and near SCS, in addition to harassment, negative encounters, fears about getting arrested, and experiences of being displaced from the area. Participants in Edmonton, despite also reporting heavy police presence near SCS, reported feeling relatively safe from police intervention and harassment, within SCS and the surrounding area. CONCLUSION: Rather than the presence/absence and quantity of policing near SCS, our findings show that the quality of policing experienced in the community shapes PWUD' perceptions, experiences, and willingness to access SCS.


Asunto(s)
Reducción del Daño , Policia , Canadá , Ciudades , Humanos , Investigación Cualitativa
10.
BMJ Open ; 11(12): e052739, 2021 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-34880021

RESUMEN

INTRODUCTION: Knowledge about the factors that contribute to the correctional officer's (CO) mental health and well-being, or best practices for improving the mental health and well-being of COs, have been hampered by the dearth of rigorous longitudinal studies. In the current protocol, we share the approach used in the Canadian Correctional Workers' Well-being, Organizations, Roles and Knowledge study (CCWORK), designed to investigate several determinants of health and well-being among COs working in Canada's federal prison system. METHODS AND ANALYSIS: CCWORK is a multiyear longitudinal cohort design (2018-2023, with a 5-year renewal) to study 500 COs working in 43 Canadian federal prisons. We use quantitative and qualitative data collection instruments (ie, surveys, interviews and clinical assessments) to assess participants' mental health, correctional work experiences, correctional training experiences, views and perceptions of prison and prisoners, and career aspirations. Our baseline instruments comprise two surveys, one interview and a clinical assessment, which we administer when participants are still recruits in training. Our follow-up instruments refer to a survey, an interview and a clinical assessment, which are conducted yearly when participants have become COs, that is, in annual 'waves'. ETHICS AND DISSEMINATION: CCWORK has received approval from the Research Ethics Board of the Memorial University of Newfoundland (File No. 20190481). Participation is voluntary, and we will keep all responses confidential. We will disseminate our research findings through presentations, meetings and publications (e.g., journal articles and reports). Among CCWORK's expected scientific contributions, we highlight a detailed view of the operational, organizational and environmental stressors impacting CO mental health and well-being, and recommendations to prison administrators for improving CO well-being.


Asunto(s)
Prisioneros , Prisiones , Canadá , Humanos , Estudios Longitudinales , Salud Mental
11.
Sci Rep ; 9(1): 15111, 2019 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-31641150

RESUMEN

Pilonidal sinus disease (PSD) is increasing globally. A recent meta-analysis and merged-data analysis showed that recurrence rates in PSD depend essentially on follow-up time and specific surgical procedures. However, the global distribution of surgical approaches and respective recurrence rates have never been studied in PSD. We aimed at studying the impact of geographic distribution of surgical approaches to treat PSD and subsequent geography-specific recurrence rates. We searched relevant databases as described previously. Recurrence rates were then associated with reported follow-up times and geographic origin. We simulated individual patients to enable analogy across data. Globally, recurrence rates range from 0.3% for Limberg/Dufourmentel approaches (95% CI 0.2-0.4) and flaps (95% CI 0.1-0.5) and up to 6.3% for incision (95% CI 3.2-9.3) at 12 months. Recurrence rates range from 0.3% for Karydakis/Bascom approaches (95% CI 0.0-0.8) up to 67.2% for incision (95% CI 7.5-100) in the USA, and 0.0% for primary asymmetric closure in Germany (95% CI 0.0-0.0). Our analysis shows that recurrence rates in PSD not only depend on therapeutic approaches and follow-up time but also on geography. Primary asymmetric closure and various flap techniques remain superior regardless of the geographical region. Some approaches have extraordinarily good outcomes in specific countries.


Asunto(s)
Geografía , Internacionalidad , Seno Pilonidal/epidemiología , Seno Pilonidal/cirugía , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Recurrencia , Resultado del Tratamiento
12.
Neurosci Lett ; 436(1): 72-6, 2008 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-18359164

RESUMEN

Axonal degeneration is now recognized as an important pathological feature of multiple sclerosis (MS). Acute axonal damage happens early in the disease course, and therefore early changes might occur in markers in body fluids, such as cerebrospinal fluid (CSF) and blood. In our study we investigated the relevance of serum and CSF markers for axonal damage in patients with clinically isolated syndrome indicative for MS. We measured the concentration of tau, phospho-tau, S100B, Amyloid beta and neuron specific enolase (NSE) in CSF and serum. Interestingly, the NSE concentration in CSF and serum was decreased in clinically isolated syndrome (CIS)-patients in comparison to the control group indicating reduced neuronal metabolic activity in the early stage of the disease. Concerning other biomarkers, we did not observe any changes in the concentrations between groups. Moreover, we did not detect any correlation between Expanded Disability Status Scale (EDSS) and the concentration of investigated proteins.


Asunto(s)
Axones/patología , Biomarcadores/análisis , Esclerosis Múltiple/metabolismo , Esclerosis Múltiple/patología , Degeneración Nerviosa/metabolismo , Adolescente , Adulto , Péptidos beta-Amiloides/análisis , Péptidos beta-Amiloides/metabolismo , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Immunoblotting , Masculino , Factores de Crecimiento Nervioso/análisis , Factores de Crecimiento Nervioso/metabolismo , Fosfopiruvato Hidratasa/análisis , Fosfopiruvato Hidratasa/metabolismo , Subunidad beta de la Proteína de Unión al Calcio S100 , Proteínas S100/análisis , Proteínas S100/metabolismo , Proteínas tau/análisis , Proteínas tau/metabolismo
13.
Chem Commun (Camb) ; 54(75): 10558-10561, 2018 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-30105315

RESUMEN

Alkoxy-substituted phenylene-ethynylene-butadiynylenes (PEBs) are connected via 1H-benzimidazole units to form H-shaped molecular scaffolds that self-assemble on graphite at the solid/liquid interface. Spacer lengths and end groups determine supramolecular tiling patterns, as shown via scanning tunneling microscopy (STM).

14.
Brain ; 128(Pt 2): 375-85, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15601662

RESUMEN

Neurodegenerative processes determine the clinical disease course of multiple sclerosis, an inflammatory autoimmune CNS disease that frequently manifests with acute optic neuritis. None of the established multiple sclerosis therapies has been shown to clearly reduce neurodegeneration. In a rat model of experimental autoimmune encephalomyelitis, we recently demonstrated increased neuronal apoptosis under methylprednisolone therapy, although CNS inflammation was effectively controlled. In the present study, we combined steroid treatment with application of erythropoietin to target inflammatory as well as neurodegenerative aspects. After immunization with myelin oligodendrocyte glycoprotein (MOG), animals were randomly assigned to six treatment groups receiving different combinations of erythropoietin and methylprednisolone, or respective monotherapies. After MOG-induced experimental autoimmune encephalomyelitis became clinically manifest, optic neuritis was monitored by recording visual evoked potentials. The function of retinal ganglion cells, the neurons that form the axons of the optic nerve, was measured by electroretinograms. Functional and histo pathological data of retinal ganglion cells and optic nerves revealed that neuron and axon protection was most effective when erythropoietin treatment that was started at immunization was combined with high-dose methylprednisolone therapy given from days 1 to 3 of MOG-induced experimental autoimmune encephalomyelitis. In contrast, isolated neuronal or axonal protection without clinical benefit was achieved under monotherapy with erythropoietin or methylprednisolone, respectively.


Asunto(s)
Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Eritropoyetina/uso terapéutico , Metilprednisolona/uso terapéutico , Esclerosis Múltiple/tratamiento farmacológico , Animales , Quimioterapia Combinada , Electrorretinografía , Encefalomielitis Autoinmune Experimental/patología , Encefalomielitis Autoinmune Experimental/fisiopatología , Potenciales Evocados Visuales , Femenino , Esclerosis Múltiple/patología , Esclerosis Múltiple/fisiopatología , Fármacos Neuroprotectores/uso terapéutico , Nervio Óptico/patología , Nervio Óptico/fisiopatología , Neuritis Óptica/patología , Neuritis Óptica/fisiopatología , Neuritis Óptica/prevención & control , Ratas , Ratas Endogámicas BN , Proteínas Recombinantes , Células Ganglionares de la Retina/patología , Células Ganglionares de la Retina/fisiología , Transducción de Señal
15.
J Neurosci ; 23(18): 6993-7000, 2003 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-12904460

RESUMEN

Optic neuritis is one of the most common clinical manifestations of multiple sclerosis (MS), a chronic inflammatory disease of the CNS. High-dosage methylprednisolone treatment has been established as the standard therapy of acute inflammation of the optic nerve (ON). The rationale for corticosteroid treatment lies in the antiinflammatory and immunosuppressive properties of these drugs, as shown in experimental autoimmune encephalomyelitis (EAE), the animal model of MS. To investigate the influence of methylprednisolone therapy on the survival of retinal ganglion cells (RGCs), the neurons that form the axons of the ON, we used a rat model of myelin oligodendrocyte glycoprotein (MOG)-induced EAE. Optic neuritis was diagnosed by recording visual evoked potentials, and RGC function was monitored by measuring electroretinograms. Methylprednisolone treatment significantly increased RGC apoptosis during MOG-EAE. By Western blot analysis, we identified the underlying molecular mechanism: a suppression of mitogen-activated protein kinase (MAPK) phosphorylation, which is a key event in an endogenous neuroprotective pathway. The methylprednisolone-induced inhibition of MAPK phosphorylation was calcium dependent. Hence, we provide evidence for negative effects of steroid treatment on neuronal survival during chronic inflammatory autoimmune disease of the CNS, which should result in a reevaluation of the current therapy regimen.


Asunto(s)
Apoptosis/efectos de los fármacos , Sistema Nervioso Central/efectos de los fármacos , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Metilprednisolona/efectos adversos , Neuronas/efectos de los fármacos , Animales , Western Blotting , Calcio/metabolismo , Canales de Calcio/metabolismo , Recuento de Células , Supervivencia Celular/efectos de los fármacos , Sistema Nervioso Central/patología , Modelos Animales de Enfermedad , Electrorretinografía , Encefalomielitis Autoinmune Experimental/inducido químicamente , Encefalomielitis Autoinmune Experimental/patología , Inhibidores Enzimáticos/farmacología , Potenciales Evocados Visuales/efectos de los fármacos , Femenino , Metilprednisolona/farmacología , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteínas de la Mielina , Glicoproteína Asociada a Mielina , Glicoproteína Mielina-Oligodendrócito , Neuronas/patología , Neuritis Óptica/inducido químicamente , Neuritis Óptica/tratamiento farmacológico , Neuritis Óptica/fisiopatología , Fosforilación/efectos de los fármacos , Ratas , Ratas Endogámicas BN , Células Ganglionares de la Retina/efectos de los fármacos , Células Ganglionares de la Retina/patología , Transducción de Señal/efectos de los fármacos
16.
BMC Med ; 3: 2, 2005 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-15629061

RESUMEN

BACKGROUND: The consistent finding of higher prevalence of hypertension in US blacks compared to whites has led to speculation that African-origin populations are particularly susceptible to this condition. Large surveys now provide new information on this issue. METHODS: Using a standardized analysis strategy we examined prevalence estimates for 8 white and 3 black populations (N = 85,000 participants). RESULTS: The range in hypertension prevalence was from 27 to 55% for whites and 14 to 44% for blacks. CONCLUSIONS: These data demonstrate that not only is there a wide variation in hypertension prevalence among both racial groups, the rates among blacks are not unusually high when viewed internationally. These data suggest that the impact of environmental factors among both populations may have been under-appreciated.


Asunto(s)
Negro o Afroamericano/estadística & datos numéricos , Hipertensión/etnología , Población Blanca/estadística & datos numéricos , Presión Sanguínea , Índice de Masa Corporal , Canadá/epidemiología , Femenino , Humanos , Jamaica/epidemiología , Masculino , Persona de Mediana Edad , Nigeria/epidemiología , Obesidad/complicaciones , Obesidad/etnología , Prevalencia , Estados Unidos/epidemiología
17.
Brain Pathol ; 14(2): 148-57, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15193027

RESUMEN

Neuronal and axonal damage is considered to be the main cause for long-term disability in multiple sclerosis. We analyzed the mechanism and kinetics of neuronal cell death in experimental autoimmune encephalomyelitis (EAE) induced by myelin oligodendrocyte glycoprotein (MOG) by combining an electrophysiological in vivo assessment of the optic pathway with the investigation of retinal ganglion cell (RGC) counts. In accordance with our previous findings in this animal model, neuritis of the optic nerve (ON) leads to apoptotic RGC death. By further investigating the time course of RGC apoptosis in the present study, we found that neuronal cell death together with decreased visual acuity values occurred before the onset of clinical symptoms. Simultaneously with the time course of RGC apoptosis, we found a down-regulation of phospho-Akt as well as a shift in the relation of 2 proteins of the Bcl-2 family, Bax and Bcl-2, towards a more proapoptotic ratio in these cells. Comparing the kinetics and mechanisms of RGC death during MOG-EAE with those following complete surgical transection of the ON, we found significant agreement. We hypothesize that the main reason for RGC loss in MOG-EAE is the inflammatory attack but RGC death also occurs independently of histopathological ON changes.


Asunto(s)
Encefalomielitis Autoinmune Experimental/patología , Degeneración Nerviosa/patología , Nervio Óptico/patología , Proteínas Serina-Treonina Quinasas , Células Ganglionares de la Retina/patología , Animales , Apoptosis/fisiología , Western Blotting , Recuento de Células , Electrofisiología , Femenino , Inmunohistoquímica , Degeneración Nerviosa/fisiopatología , Nervio Óptico/fisiopatología , Traumatismos del Nervio Óptico/patología , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-akt , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Ratas , Factores de Tiempo
18.
Brain Pathol ; 14(4): 378-87, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15605985

RESUMEN

Multiple sclerosis (MS) is a chronic inflammatory disease of the CNS which leads to demyelination, axonal destruction and neuronal loss in the early stages. Available therapies mainly target the inflammatory component of the disease but fail to prevent neurodegeneration. To investigate the effect of ciliary neurotrophic factor (CNTF) on the survival of retinal ganglion cells (RGCs), the neurons that form the axons of the optic nerve, we used a rat model of myelin oligodendrocyte glycoprotein-induced experimental autoimmune encephalomyelitis. Optic neuritis in this model was diagnosed by recording visual evoked potentials, and RGC function was monitored by measuring electroretinograms. This study demonstrates that CNTF has a neuroprotective effect on affected RGCs during acute optic neuritis. Furthermore, we demonstrate that CNTF exerts its neuroprotective effect through activation of the Janus kinase/signal transducer and activator of transcription pathway, mitogen activated protein kinases and a shift in the Bcl-2 family of proteins towards the anti-apoptotic side. In summary, our results demonstrate that CNTF can serve as an effective neuroprotective treatment in a rat model of MS that especially reflects the neurodegenerative aspects of this disease.


Asunto(s)
Factor Neurotrófico Ciliar/uso terapéutico , Degeneración Nerviosa/prevención & control , Neuritis Óptica/prevención & control , Células Ganglionares de la Retina/efectos de los fármacos , Análisis de Varianza , Animales , Western Blotting/métodos , Recuento de Células/métodos , Muerte Celular/efectos de los fármacos , Proteínas de Unión al ADN/metabolismo , Combinación de Medicamentos , Inhibidores Enzimáticos/administración & dosificación , Potenciales Evocados Visuales/efectos de los fármacos , Potenciales Evocados Visuales/fisiología , Femenino , Flavonoides/administración & dosificación , Colorantes Fluorescentes , Regulación de la Expresión Génica/efectos de los fármacos , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Degeneración Nerviosa/etiología , Nervio Óptico/efectos de los fármacos , Nervio Óptico/metabolismo , Nervio Óptico/patología , Neuritis Óptica/patología , Estimulación Luminosa/métodos , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Ratas , Factor de Transcripción STAT3 , Estilbamidinas , Factores de Tiempo , Transactivadores/metabolismo , Corteza Visual/efectos de los fármacos , Corteza Visual/fisiopatología , Proteína X Asociada a bcl-2
19.
Neurobiol Dis ; 25(3): 514-25, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17239606

RESUMEN

Axonal destruction and neuronal loss occur early during multiple sclerosis, an autoimmune inflammatory CNS disease that frequently manifests with acute optic neuritis. Available therapies mainly target the inflammatory component of the disease but fail to prevent neurodegeneration. To investigate the effect of minocycline on the survival of retinal ganglion cells (RGCs), the neurons that form the axons of the optic nerve, we used a rat model of myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis. Optic neuritis in this model was diagnosed by recording visual evoked potentials and RGC function was monitored by measuring electroretinograms. Functional and histopathological data of RGCs and optic nerves revealed neuronal and axonal protection when minocycline treatment was started on the day of immunization. Furthermore, we demonstrate that minocycline-induced neuroprotection is related to a direct antagonism of multiple mechanisms leading to neuronal cell death such as the induction of anti-apoptotic intracellular signalling pathways and a decrease in glutamate excitotoxicity. From these observations, we conclude that minocycline exerts neuroprotective effects independent of its anti-inflammatory properties. This hypothesis was confirmed in a non-inflammatory disease model leading to degeneration of RGCs, the surgical transection of the optic nerve.


Asunto(s)
Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Encefalomielitis Autoinmune Experimental/inmunología , Minociclina/farmacología , Fármacos Neuroprotectores/farmacología , Enfermedad Aguda , Animales , Antibacterianos/sangre , Antibacterianos/líquido cefalorraquídeo , Antibacterianos/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/inmunología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/inmunología , Encefalomielitis Autoinmune Experimental/fisiopatología , Potenciales Evocados Visuales , Transportador 1 de Aminoácidos Excitadores/metabolismo , Transportador 2 de Aminoácidos Excitadores/metabolismo , Transportador 3 de Aminoácidos Excitadores/metabolismo , Femenino , Ácido Glutámico/metabolismo , Minociclina/sangre , Minociclina/líquido cefalorraquídeo , Proteínas de la Mielina , Glicoproteína Asociada a Mielina/inmunología , Glicoproteína Mielina-Oligodendrócito , Fármacos Neuroprotectores/sangre , Fármacos Neuroprotectores/líquido cefalorraquídeo , Nervio Óptico/inmunología , Nervio Óptico/patología , Nervio Óptico/fisiopatología , Neuritis Óptica/tratamiento farmacológico , Neuritis Óptica/inmunología , Neuritis Óptica/fisiopatología , Ratas , Ratas Endogámicas BN , Células Ganglionares de la Retina/inmunología , Células Ganglionares de la Retina/metabolismo , Células Ganglionares de la Retina/patología , Índice de Severidad de la Enfermedad
20.
Am J Pathol ; 169(4): 1353-64, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17003491

RESUMEN

Axonal destruction and neuronal loss occur early during multiple sclerosis (MS), an autoimmune inflammatory central nervous system disease that frequently manifests with acute optic neuritis. Glatiramer acetate (GA) and interferon-beta-1b (IFN-beta-1b) are two immunomodulatory agents that have been shown to decrease the frequency of MS relapses. However, the question of whether these substances can slow neurodegeneration in MS patients is the subject of controversy. In a rat model of experimental autoimmune encephalomyelitis, we investigated the effects of GA and IFN-beta-1b on the survival of retinal ganglion cells (RGCs), the neurons that form the axons of the optic nerve. For each substance, therapy was started 14 days before immunization, on the day of immunization, or on the day of clinical disease onset. After myelin oligodendrocyte glycoprotein-induced experimental autoimmune encephalomyelitis became clinically manifest, optic neuritis was monitored by recording visual evoked potentials. The function of RGCs was measured by electroretinograms. Although early GA or IFN-beta-1b treatment showed benefit on disease activity, only treatment with GA exerted protective effects on RGCs, as revealed by measuring neurodegeneration and neuronal function. Furthermore, we demonstrate that this GA-induced neuroprotection does not exclusively depend on the reduction of inflammatory infiltrates within the optic nerve.


Asunto(s)
Encefalomielitis Autoinmune Experimental/prevención & control , Interferón beta/uso terapéutico , Esclerosis Múltiple/prevención & control , Fármacos Neuroprotectores/uso terapéutico , Péptidos/uso terapéutico , Células Ganglionares de la Retina/efectos de los fármacos , Animales , Axones/patología , Supervivencia Celular , Electrorretinografía , Encefalomielitis Autoinmune Experimental/patología , Potenciales Evocados Visuales , Femenino , Acetato de Glatiramer , Interferon beta-1b , Esclerosis Múltiple/patología , Vaina de Mielina/patología , Enfermedades Neurodegenerativas/prevención & control , Nervio Óptico/efectos de los fármacos , Nervio Óptico/patología , Neuritis Óptica/patología , Neuritis Óptica/fisiopatología , Neuritis Óptica/prevención & control , Ratas , Ratas Endogámicas BN , Células Ganglionares de la Retina/patología
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