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Ablation has been shown to be an effective option for treatment of well-selected patients with thyroid nodules, particularly benign nodules, and thermal ablation is being increasingly used for this purpose. The general approach to thermal ablation of the thyroid will be familiar to interventional radiologists who perform ablation in other tissues; however, thermal ablation of the thyroid has additional unique considerations. In this review, we provide evidence-based and real-world guidance on the performance of thermal ablation for the treatment of patients with thyroid nodules, drawing on our collective experience and clinical practice. We describe patient selection, ablation modalities, equipment, general procedural approach, additional technical considerations, and postprocedural follow-up. We discuss various clinical scenarios; give tips on performing specific portions of the procedure and highlight a range of relevant anatomic, biochemical, and clinical factors, as a guide for interventional radiologists in establishing a successful thyroid ablation practice.
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BACKGROUND: Slowed processing speed impacts employment status in people with multiple sclerosis (PwMS). Studies on the Multiple Sclerosis Functional Composite (MSFC), which includes the Paced Auditory Serial Addition Test (PASAT), have demonstrated that the combined score predicts employment status. Whether PASAT performance alone is associated with employment status is less clear. In addition, no studies have yet evaluated whether cognitive fatigability (CF), as measured with the PASAT, is associated with employment status. The aim of the current study was to examine the association between PASAT performance, CF, and employment status in PwMS. METHODS: Hundred and eighty-six PwMS completed the PASAT as part of a larger neuropsychological battery. ANOVAs and chi-squares analyzed group differences between employed and unemployed participants with respect to demographics, PASAT performance scores, and CF. Linear regression determined whether PASAT performance and/or CF scores were associated with employment status. RESULTS: After controlling for demographic influences, group differences were noted between employed vs. unemployed individuals on PASAT performance scores only. Employment status was associated with PASAT performance scores but not CF. CONCLUSIONS: The current study confirmed that PASAT performance is associated with employment status in MS. Given that CF was not associated, it seems difficulties with information processing speed (IPS) and working memory have more impact on a PwMS's ability to remain employed rather than within-task performance decline.
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Cytolethal distending toxins (Cdt) are produced by a diverse group of pathogens. One Cdt-producing organism, Aggregatibacter actinomycetemcomitans, plays a critical role in the pathogenesis of a unique form of periodontitis, formerly referred to as localized aggressive periodontitis. The active Cdt subunit, CdtB, is a potent phosphatidylinositol (PI) 3,4,5-triphosphate phosphatase capable of inducing PI-3-kinase signaling blockade, a requisite for Cdt-induced toxicity in lymphocytes. In this study, we extended our observations to include the oral keratinocyte response to AaCdt using cell lines and primary gingival keratinocytes. All three exhibited G2/M arrest when exposed to AaCdt toxin within 24 h. Toxin-treated cells exhibited reduced levels of pAkt and pGSK3ß within 6 h. Pre-treatment with GSK3ß kinase inhibitors, LY2090314, CHIR99021 and Tideglusib, abrogated Cdt-induced G2/M arrest. None of the oral epithelial cells exhibited evidence of apoptosis. Cells remained arrested in the G2/M phase for at least 72 h without evidence of DNA damage response activation (H2AX phosphorylation). Cdt-treated cells displayed increased phosphorylation of the cyclin dependent kinase 1 (CDK1); moreover, the GSK3 inhibitors blocked this increase and reduced total CDK1 levels. This study further clarifies the potential mechanism(s) contributing to Cdt toxicity and toxin-mediated pathogenesis.
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Aggregatibacter actinomycetemcomitans , Periodontite Agressiva , Apoptose , Toxinas Bacterianas , Proteína Quinase CDC2/metabolismo , Ciclo Celular , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Pontos de Checagem da Fase G2 do Ciclo Celular , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Queratinócitos , Fosfatidilinositóis/metabolismo , Monoéster Fosfórico Hidrolases/metabolismoRESUMO
Cytolethal distending toxins (Cdt) are a family of toxins produced by several human pathogens which infect mucocutaneous tissue and induce inflammatory disease. We have previously demonstrated that the Aggregatibacter actinomycetemcomitans Cdt induces a pro-inflammatory response from human macrophages which involves activation of the NLRP3 inflammasome. We now demonstrate that in addition to activating caspase-1 (canonical inflammasome), Cdt treatment leads to caspase-4 activation and involvement of the noncanonical inflammasome. Cdt-treated cells exhibit pyroptosis characterised by cleavage of gasdermin-D (GSDMD), release of HMGB1 at 24 hr and LDH at 48 hr. Inhibition of either the canonical (caspase-1) or noncanonical (caspase-4) inflammasome blocks both Cdt-induced release of IL-1ß and induction of pyroptosis. Analysis of upstream events indicates that Cdt induces Syk phosphorylation (activation); furthermore, blockade of Syk expression and inhibition of pSyk activity inhibit both Cdt-induced cytokine release and pyroptosis. Finally, we demonstrate that increases in pSyk are dependent upon Cdt-induced activation of GSK3ß. These studies advance our understanding of Cdt function and provide new insight into the virulence potential of Cdt in mediating the pathogenesis of disease caused by Cdt-producing organisms such as A. actinomycetemcomitans.
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Toxinas Bacterianas/efeitos adversos , Glicogênio Sintase Quinase 3 beta/metabolismo , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Macrófagos/metabolismo , Quinase Syk/metabolismo , Caspase 1/metabolismo , Caspases Iniciadoras/metabolismo , Citocinas/metabolismo , Proteína HMGB1/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Piroptose , Células THP-1RESUMO
BACKGROUND: Germline TP53 gene pathogenic variants (pv) cause a very high lifetime risk of developing cancer, almost 100% for women and 75% for men. In the UK, annual MRI breast screening is recommended for female TP53 pv carriers. The SIGNIFY study (Magnetic Resonance Imaging screening in Li Fraumeni syndrome: An exploratory whole body MRI) study reported outcomes of whole-body MRI (WB-MRI) in a cohort of 44 TP53 pv carriers and 44 matched population controls. The results supported the use of a baseline WB-MRI screen in all adult TP53 pv carriers. Here we report the acceptability of WB-MRI screening and effects on psychosocial functioning and health-related quality of life in the short and medium terms. METHODS: Psychosocial and other assessments were carried out at study enrolment, immediately before MRI, before and after MRI results, and at 12, 26 and 52 weeks' follow-up. RESULTS: WB-MRI was found to be acceptable with high levels of satisfaction and low levels of psychological morbidity throughout. Although their mean levels of cancer worry were not high, carriers had significantly more cancer worry at most time-points than controls. They also reported significantly more clinically significant intrusive and avoidant thoughts about cancer than controls at all time-points. There were no clinically significant adverse psychosocial outcomes in either carriers with a history of cancer or in those requiring further investigations. CONCLUSION: WB-MRI screening can be implemented in TP53 pv carriers without adverse psychosocial outcomes in the short and medium terms. A previous cancer diagnosis may predict a better psychosocial outcome. Some carriers seriously underestimate their risk of cancer. Carriers of pv should have access to a clinician to help them develop adaptive strategies to cope with cancer-related concerns and respond to clinically significant depression and/or anxiety.
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Síndrome de Li-Fraumeni/diagnóstico , Imageamento por Ressonância Magnética , Neoplasias/diagnóstico , Proteína Supressora de Tumor p53/genética , Adulto , Feminino , Predisposição Genética para Doença , Mutação em Linhagem Germinativa/genética , Heterozigoto , Humanos , Síndrome de Li-Fraumeni/diagnóstico por imagem , Síndrome de Li-Fraumeni/genética , Síndrome de Li-Fraumeni/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias/diagnóstico por imagem , Neoplasias/genética , Neoplasias/patologia , Fatores de Risco , Imagem Corporal Total , Adulto JovemRESUMO
BACKGROUND: No normative data currently exist that would allow clinicians to decide whether the degree of cognitive fatigability (CF) experienced in individuals with neurologic disease is greater than expected when compared with a healthy population. OBJECTIVE: To establish discrete and regression-based normative data for CF as defined by an objective decrement in performance over the course of a cognitive task; namely, the Paced Auditory Serial Addition Test (PASAT). In addition, to develop discrete and regression-based normative data for PASAT performance scores-dyad and percent dyad-for which data do not currently exist. METHOD: One hundred and seventy-eight healthy individuals completed the PASAT as part of a larger neuropsychological battery. PASAT performance scores including total correct responses, total dyads, and percent dyad were calculated. CF scores were calculated by comparing the individuals' performance on the first half (or third) of the test to their performance on the last half (or third) in order to capture any within-task performance decrements over time. RESULTS: Both age- and education-based discrete normative data and demographically adjusted (sex, age, and education) regression-based formulas were established for the PASAT performance scores and the CF scores. CONCLUSION: The development of these normative data will allow for greater interpretation of an individual's performance on the PASAT, beyond just the total correct score, through the use of dyad and percent dyad scores. With respect to CF, these data will allow clinicians to objectively quantify decrements in cognitive performance over time better in individuals with neurologic diseases.
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Transtornos Cognitivos , Cognição , Fadiga , Transtornos Cognitivos/diagnóstico , Escolaridade , Humanos , Testes NeuropsicológicosRESUMO
The Sound Judgment Series consists of invited articles highlighting the clinical value of using ultrasound first in specific clinical diagnoses where ultrasound has shown comparative or superior value. The series is meant to serve as an educational tool for medical and sonography students and clinical practitioners and may help integrate ultrasound into clinical practice.
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Anticoncepcionais , Implantes de Medicamento , Humanos , UltrassonografiaRESUMO
The onset of the COVID-19 pandemic in March 2020 required hospitals to respond quickly and effectively to ensure the availability of healthcare professionals to care for patients. The Ottawa Hospital in Ottawa, ON, used a five-step process to ensure organizational readiness for redeployment of regulated health professionals as and when necessary: (1) define current scopes of practice; (2) obtain discipline-specific input; (3) develop strategies based on literature review and government dictates; (4) identify potential duties; and (5) ensure support for staff. With hospital management support, this plan was readily implemented. Results are discussed in terms of operational outcomes (e.g., number and type of deployments) and staff experience. Outcomes were positive and led to recommendations for improved organizational readiness.
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COVID-19/epidemiologia , Educação Interprofissional , Administração de Recursos Humanos em Hospitais , Planejamento Hospitalar , Humanos , Educação Interprofissional/métodos , Educação Interprofissional/organização & administração , Liderança , Ontário/epidemiologia , Administração de Recursos Humanos em Hospitais/métodos , Recursos Humanos em Hospital/provisão & distribuiçãoRESUMO
Improved sequencing technologies offer unprecedented opportunities for investigating the role of rare genetic variation in common disease. However, there are considerable challenges with respect to study design, data analysis and replication. Using pooled next-generation sequencing of 507 genes implicated in the repair of DNA in 1,150 samples, an analytical strategy focused on protein-truncating variants (PTVs) and a large-scale sequencing case-control replication experiment in 13,642 individuals, here we show that rare PTVs in the p53-inducible protein phosphatase PPM1D are associated with predisposition to breast cancer and ovarian cancer. PPM1D PTV mutations were present in 25 out of 7,781 cases versus 1 out of 5,861 controls (P = 1.12 × 10(-5)), including 18 mutations in 6,912 individuals with breast cancer (P = 2.42 × 10(-4)) and 12 mutations in 1,121 individuals with ovarian cancer (P = 3.10 × 10(-9)). Notably, all of the identified PPM1D PTVs were mosaic in lymphocyte DNA and clustered within a 370-base-pair region in the final exon of the gene, carboxy-terminal to the phosphatase catalytic domain. Functional studies demonstrate that the mutations result in enhanced suppression of p53 in response to ionizing radiation exposure, suggesting that the mutant alleles encode hyperactive PPM1D isoforms. Thus, although the mutations cause premature protein truncation, they do not result in the simple loss-of-function effect typically associated with this class of variant, but instead probably have a gain-of-function effect. Our results have implications for the detection and management of breast and ovarian cancer risk. More generally, these data provide new insights into the role of rare and of mosaic genetic variants in common conditions, and the use of sequencing in their identification.
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Neoplasias da Mama/genética , Predisposição Genética para Doença/genética , Mosaicismo , Mutação , Neoplasias Ovarianas/genética , Fosfoproteínas Fosfatases/genética , Alelos , Análise por Conglomerados , Éxons , Feminino , Humanos , Isoenzimas/genética , Linfócitos/metabolismo , Proteína Fosfatase 2C , Análise de Sequência de DNA , Proteína Supressora de Tumor p53/metabolismoRESUMO
PURPOSE: BRCA1/BRCA2 predictive test negatives are proven noncarriers of a BRCA1/BRCA2 mutation that is carried by their relatives. The risk of developing breast cancer (BC) or epithelial ovarian cancer (EOC) in these women is uncertain. The study aimed to estimate risks of invasive BC and EOC in a large cohort of BRCA1/BRCA2 predictive test negatives. METHODS: We used cohort analysis to estimate incidences, cumulative risks, and standardized incidence ratios (SIRs). RESULTS: A total of 1,895 unaffected women were eligible for inclusion in the BC risk analysis and 1,736 in the EOC risk analysis. There were 23 incident invasive BCs and 2 EOCs. The cumulative risk of invasive BC was 9.4% (95% confidence interval (CI) 5.9-15%) by age 85 years and the corresponding risk of EOC was 0.6% (95% CI 0.2-2.6%). The SIR for invasive BC was 0.93 (95% CI 0.62-1.40) in the overall cohort, 0.85 (95% CI 0.48-1.50) in noncarriers from BRCA1 families, and 1.03 (95% CI 0.57-1.87) in noncarriers from BRCA2 families. The SIR for EOC was 0.79 (95% CI 0.20-3.17) in the overall cohort. CONCLUSION: Our results did not provide evidence for elevated risks of invasive BC or EOC in BRCA1/BRCA2 predictive test negatives.
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Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Neoplasias Ovarianas/genética , Adulto , Idoso , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Feminino , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/epidemiologia , Medição de Risco , Fatores de RiscoRESUMO
BACKGROUND: The protective effect of cognitive reserve (CR) on cognition in people with multiple sclerosis (PwMS) has been well described. OBJECTIVE: To explore the relationship between aspects of CR, namely, leisure pursuits and depression. METHODS: In a cross-sectional study, a sample of 155 PwMS and 115 healthy controls (HC) underwent cognitive testing with the Minimal Assessment of Cognitive Function in Multiple Sclerosis (MACFIMS) battery. Leisure activity was retrospectively recorded using the Leisure Activity Scale (LAS). Depression was assessed using the Hospital Anxiety and Depression Scale. RESULTS: PwMS demonstrated greater decreases in leisure activity over time compared to the HC group, particularly in the past year ( p < 0.001). Here, depression accounted for 17% of the variance in determining the level of leisure activity ( p < 0.001). Premorbid IQ and leisure activity within the past year emerged as significant predictors of information processing speed, learning, memory and executive function. After controlling for depression, the influence of leisure activity on cognition was insignificant. CONCLUSION: Depression can cause significant changes in behaviour which can influence indices of CR, such as leisure pursuits. Successfully treating depression may lead to a more active lifestyle thereby offsetting in part the cognitive burden of disease.
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Disfunção Cognitiva/fisiopatologia , Reserva Cognitiva/fisiologia , Depressão/fisiopatologia , Atividades de Lazer , Esclerose Múltipla/fisiopatologia , Adulto , Idoso , Disfunção Cognitiva/etiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicaçõesRESUMO
Multiple sclerosis (MS) is a chronic, progressive, autoimmune, neurodegenerative disorder that can interfere with physical and psychological functioning, negatively affecting health-related quality of life (HRQoL). Fostering mindfulness may mitigate the negative consequences of MS on HRQoL. The relationship between mindfulness, mood and MS-related quality of life was investigated. In total, 52 individuals with MS completed questionnaires to examine the relationship between trait mindfulness and wellness. Higher levels of trait mindfulness were associated with better HRQoL, lower depression and anxiety, lower fatigue impact and fewer perceived cognitive deficits. Mindfulness interventions have the potential to enhance wellness in those living with MS.
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Conscientização , Atenção Plena , Esclerose Múltipla/complicações , Esclerose Múltipla/psicologia , Qualidade de Vida/psicologia , Adulto , Transtornos Cognitivos/etiologia , Fadiga/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos do Humor/etiologia , Dor/etiologia , Inquéritos e QuestionáriosRESUMO
Medical device biocompatibility testing is used to evaluate the risk of adverse effects on tissues from exposure to leachates/extracts. A battery of tests is typically recommended in accordance with regulatory standards to determine if the device is biocompatible. In vitro cytotoxicity, a key element of the standards, is a required endpoint for all types of medical devices. Each validated cytotoxicity method has different methodology and acceptance criteria that could influence the selection of a specific test. In addition, some guidances are more specific than others as to the recommended test methods. For example, the International Organization for Standardization (ISO1) cites preference for quantitative methods (e.g., tetrazolium (MTT/XTT), neutral red (NR), or colony formation assays (CFA)) over qualitative methods (e.g., elution, agar overlay/diffusion, or direct), while a recent ISO standard for contact lens/lens care solutions specifically requires a qualitative direct test. Qualitative methods are described in United States Pharmacopeia (USP) while quantitative CFAs are listed in Japan guidance. The aim of this review is to compare the methodologies such as test article preparation, test conditions, and criteria for six cytotoxicity methods recommended in regulatory standards in order to inform decisions on which method(s) to select during the medical device safety evaluation.
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Materiais Biocompatíveis/farmacologia , Segurança de Equipamentos , Teste de Materiais , Animais , Sobrevivência Celular/efeitos dos fármacos , HumanosRESUMO
BACKGROUND: Patients with heterozygous germline mutations in phosphatase and tensin homolog deleted on chromosome 10 (PTEN) experience autoimmunity and lymphoid hyperplasia. OBJECTIVES: Because regulation of the phosphoinositide 3-kinase (PI3K) pathway is critical for maintaining regulatory T (Treg) cell functions, we investigate Treg cells in patients with heterozygous germline PTEN mutations (PTEN hamartoma tumor syndrome [PHTS]). METHODS: Patients with PHTS were assessed for immunologic conditions, lymphocyte subsets, forkhead box P3 (FOXP3)+ Treg cell levels, and phenotype. To determine the functional importance of phosphatases that control the PI3K pathway, we assessed Treg cell induction in vitro, mitochondrial depolarization, and recruitment of PTEN to the immunologic synapse. RESULTS: Autoimmunity and peripheral lymphoid hyperplasia were found in 43% of 79 patients with PHTS. Immune dysregulation in patients with PHTS included lymphopenia, CD4+ T-cell reduction, and changes in T- and B-cell subsets. Although total CD4+FOXP3+ Treg cell numbers are reduced, frequencies are maintained in the blood and intestine. Despite pathogenic PTEN mutations, the FOXP3+ T cells are phenotypically normal. We show that the phosphatase PH domain leucine-rich repeat protein phosphatase (PHLPP) downstream of PTEN is highly expressed in normal human Treg cells and provides complementary phosphatase activity. PHLPP is indispensable for the differentiation of induced Treg cells in vitro and Treg cell mitochondrial fitness. PTEN and PHLPP form a phosphatase network that is polarized at the immunologic synapse. CONCLUSION: Heterozygous loss of function of PTEN in human subjects has a significant effect on T- and B-cell immunity. Assembly of the PTEN-PHLPP phosphatase network allows coordinated phosphatase activities at the site of T-cell receptor activation, which is important for limiting PI3K hyperactivation in Treg cells despite PTEN haploinsufficiency.
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Linfócitos B/fisiologia , Síndrome do Hamartoma Múltiplo/imunologia , Sinapses Imunológicas/metabolismo , Subpopulações de Linfócitos/fisiologia , Proteínas Nucleares/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Linfócitos T Reguladores/fisiologia , Adolescente , Adulto , Idoso , Autoimunidade , Células Cultivadas , Criança , Fatores de Transcrição Forkhead/metabolismo , Síndrome do Hamartoma Múltiplo/genética , Humanos , Hiperplasia , Masculino , Potencial da Membrana Mitocondrial , Pessoa de Meia-Idade , Mutação/genética , PTEN Fosfo-Hidrolase/genética , Ligação Proteica , Transporte Proteico , Transdução de Sinais , Adulto JovemRESUMO
For over 30 years, researchers have examined social influence using status characteristics theory (Berger and Conner, 1974). While research has investigated beauty and attractiveness as status characteristics (e.g., Webster and Driskell, 1983), there is a dearth of research that examines whether obesity has status value using status characteristics theory. The current paper reviews the literature on, demonstrating how they are related to status characteristics. Next, this paper demonstrates how the effects of both gender and obesity can be explained by considering them as status characteristics, which have the potential to create subsequent status beliefs and stigma. Finally, this study reports empirical findings that support obesity as a status characteristic. We find an effect for obesity on ratings of diffuse status, and effects for both obesity and gender on ratings of influence.
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BACKGROUND: Strong immunosuppression, including chemotherapy and immune-depleting antibodies followed by autologous haemopoietic stem-cell transplantation (aHSCT), has been used to treat patients with multiple sclerosis, improving control of relapsing disease. We addressed whether near-complete immunoablation followed by immune cell depleted aHSCT would result in long-term control of multiple sclerosis. METHODS: We did this phase 2 single-arm trial at three hospitals in Canada. We enrolled patients with multiple sclerosis, aged 18-50 years with poor prognosis, ongoing disease activity, and an Expanded Disability Status Scale of 3.0-6.0. Autologous CD34 selected haemopoietic stem-cell grafts were collected after mobilisation with cyclophosphamide and filgrastim. Immunoablation with busulfan, cyclophosphamide, and rabbit anti-thymocyte globulin was followed by aHSCT. The primary outcome was multiple sclerosis activity-free survival (events were clinical relapse, appearance of a new or Gd-enhancing lesion on MRI, and sustained progression of Expanded Disability Status Scale score). This study was registered at ClinicalTrials.gov, NCT01099930. FINDINGS: Between diagnosis and aHSCT, 24 patients had 167 clinical relapses over 140 patient-years with 188 Gd-enhancing lesions on 48 pre-aHSCT MRI scans. Median follow-up was 6.7 years (range 3.9-12.7). The primary outcome, multiple sclerosis activity-free survival at 3 years after transplantation was 69.6% (95% CI 46.6-84.2). With up to 13 years of follow-up after aHSCT, no relapses occurred and no Gd enhancing lesions or new T2 lesions were seen on 314 MRI sequential scans. The rate of brain atrophy decreased to that expected for healthy controls. One of 24 patients died of transplantation-related complications. 35% of patients had a sustained improvement in their Expanded Disability Status Scale score. INTERPRETATION: We describe the first treatment to fully halt all detectable CNS inflammatory activity in patients with multiple sclerosis for a prolonged period in the absence of any ongoing disease-modifying drugs. Furthermore, many of the patients had substantial recovery of neurological function despite their disease's aggressive nature. FUNDING: Multiple Sclerosis Scientific Research Foundation.
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Transplante de Células-Tronco Hematopoéticas/métodos , Imunossupressores/uso terapêutico , Esclerose Múltipla/terapia , Adolescente , Adulto , Soro Antilinfocitário/uso terapêutico , Bussulfano/uso terapêutico , Ciclofosfamida/uso terapêutico , Progressão da Doença , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/tratamento farmacológico , Condicionamento Pré-Transplante , Transplante Autólogo , Adulto JovemRESUMO
BACKGROUND: Cognitive dysfunction in multiple sclerosis (MS) causes numerous limitations in activities of daily living. OBJECTIVES: To develop an improved method of cognitive assessment in people with MS using novel real-world distracters. METHODS: A sample of 99 people with MS and 55 demographically matched healthy controls underwent testing with the Minimal Assessment of Cognitive Functioning in Multiple Sclerosis (MACFIMS) and a modified version of the computerized Symbol Digit Modalities Test (c-SDMT). Half of the subjects completed the c-SDMT with built-in real-world distracters and half without. RESULTS: The mean time on the c-SDMT was significantly greater in MS subjects than healthy controls for both distracter ( p = 0.001) and non-distracter ( p < 0.001) versions. Significantly more MS subjects were impaired on the c-SDMT with distracters than the traditional SDMT (47.1% vs 30.3%, p = 0.04). There were no differences in impairment between the c-SDMT with and without distracters (47.1% vs 37.5%, p = 0.34). The distracter version had a sensitivity of 81% and specificity of 88% in detecting global cognitive impairment. CONCLUSIONS: The incorporation of distracters improves the sensitivity of a validated computerized version of the SDMT relative to the non-distracter and traditional versions and offers a quick and easy means of detecting cognitive impairment in people with MS.
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Transtornos Cognitivos/fisiopatologia , Cognição/fisiologia , Esclerose Múltipla/fisiopatologia , Testes Neuropsicológicos , Atividades Cotidianas , Adulto , Transtornos Cognitivos/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Esclerose Múltipla/diagnóstico , Adulto JovemRESUMO
The Aggregatibacter actinomycetemcomitans cytolethal distending toxin (Cdt) induces G2 arrest and apoptosis in lymphocytes and other cell types. We have shown that the active subunit, CdtB, exhibits phosphatidylinositol-3,4,5-triphosphate (PIP3) phosphatase activity, leading us to propose that Cdt toxicity is the result of PIP3 depletion and perturbation of phosphatidylinositol-3-kinase (PI-3K)/PIP3/Akt signalling. To further explore this relationship, we have focused our analysis on identifying residues that comprise the catalytic pocket and are critical to substrate binding rather than catalysis. In this context, we have generated several CdtB mutants and demonstrate that, in each instance, the ability of the toxin to induce cell cycle arrest correlates with retention of phosphatase activity. We have also assessed the effect of Cdt on downstream components of the PI-3K signalling pathway. In addition to depletion of intracellular concentrations of PIP3, toxin-treated lymphocytes exhibit decreases in pAkt and pGSK3ß. Further analysis indicates that toxin-treated cells exhibit a concomitant loss in Akt activity and increase in GSK3ß kinase activity consistent with observed changes in their phosphorylation status. We demonstrate that cell susceptibility to Cdt is dependent upon dephosphorylation and concomitant activation of GSK3ß. Finally, we demonstrate that, in addition to lymphocytes, HeLa cells exposed to a CdtB mutant that retains phosphatase activity and not DNase activity undergo G2 arrest in the absence of H2AX phosphorylation. Our results provide further insight into the mode of action by which Cdt may function as an immunotoxin and induce cell cycle arrest in target cells such as lymphocytes.