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1.
J Biol Chem ; 298(9): 102348, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35933009

RESUMO

Progranulin (PGRN) is a glycoprotein implicated in several neurodegenerative diseases. It is highly expressed in microglia and macrophages and can be secreted or delivered to the lysosome compartment. PGRN comprises 7.5 granulin repeats and is processed into individual granulin peptides within the lysosome, but the functions of these peptides are largely unknown. Here, we identify CD68, a lysosome membrane protein mainly expressed in hematopoietic cells, as a binding partner of PGRN and PGRN-derived granulin E. Deletion analysis of CD68 showed that this interaction is mediated by the mucin-proline-rich domain of CD68. While CD68 deficiency does not affect the lysosomal localization of PGRN, it results in a specific decrease in the levels of granulin E but no other granulin peptides. On the other hand, the deficiency of PGRN, and its derivative granulin peptides, leads to a significant shift in the molecular weight of CD68, without altering CD68 localization within the cell. Our results support that granulin E and CD68 reciprocally regulate each other's protein homeostasis.


Assuntos
Antígenos CD , Antígenos de Diferenciação Mielomonocítica , Granulinas , Proteínas de Membrana Lisossomal , Proteostase , Granulinas/metabolismo , Proteínas de Membrana Lisossomal/metabolismo , Lisossomos/metabolismo , Mucinas/metabolismo , Progranulinas/metabolismo , Prolina/metabolismo
2.
Ann Neurol ; 90(3): 440-454, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34231919

RESUMO

OBJECTIVE: Histology reveals that early active multiple sclerosis lesions can be classified into 3 main interindividually heterogeneous but intraindividually stable immunopathological patterns of active demyelination (patterns I-III). In patterns I and II, a T-cell- and macrophage-associated demyelination is suggested, with pattern II only showing signs of a humoral immune response. Pattern III is characterized by inflammatory lesions with an oligodendrocyte degeneration. Patterns suggest pathogenic heterogeneity, and we postulated that they have distinct magnetic resonance imaging (MRI) correlates that may serve as biomarkers. METHODS: We evaluated in an international collaborative retrospective cohort study the MRI lesion characteristics of 789 conventional prebiopsy and follow-up MRIs in relation to their histopathologically classified immunopathological patterns (n = 161 subjects) and lesion edge features (n = 112). RESULTS: A strong association of a ringlike enhancement and a hypointense T2-weighted (T2w) rim with patterns I and II, but not pattern III, was observed. Only a fraction of pattern III patients showed a ringlike enhancement, and this was always atypical. Ringlike enhancement and T2w rims colocalized, and ringlike enhancement showed a strong association with macrophage rims as shown by histology. A strong concordance of MRI lesion characteristics, meaning that different lesions showed the same features, was found when comparing biopsied and nonbiopsied lesions at a given time point, indicating lesion homogeneity within individual patients. INTERPRETATION: We provide robust evidence that MRI characteristics reflect specific morphological features of multiple sclerosis immunopatterns and that ringlike enhancement and T2w hypointense rims might serve as a valuable noninvasive biomarker to differentiate pathological patterns of demyelination. ANN NEUROL 2021;90:440-454.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/imunologia , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/imunologia , Adulto , Encéfalo/patologia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/patologia , Estudos Retrospectivos
3.
Q J Nucl Med Mol Imaging ; 66(2): 171-178, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31922369

RESUMO

BACKGROUND: PET-CT with 18F-FDG or other radiopharmaceuticals is a recommended tool to help the delineation of lung cancers candidate to radiotherapy. The motion artifacts caused by respiratory movements are reduced by 4D acquisitions. We introduced an extended reconstruction algorithm (multiple reconstruct register and average [multi-RRA]) which requires much shorter acquisition times than standard 4D PET-CT. Our aim was to evaluate the interest on multi-RRA images as an alternative of 3D and 4D PET-CT for the delineation of lung lesion. METHODS: PET acquisitions synchronized to the respiratory signal were obtained in 18 patients with mobile lung tumors. We compared the tumor volumes delineated on Multi-RRA images to 3D and 4D PET-CT, considering the 4D CT as a reference. The tumor volumes were delineated and compared with topologic similarity indexes (Dice, Jaccard and overlap). RESULTS: Twenty tumors were delineated. The volumes delineated with multi-RRA and 4D PET were not significantly different (mean difference of 0.2±0.7 mL). Comparison by pairs (Tukey-Kramer test) showed that 3D-PET volumes were significantly smaller than 4D-PET and multi-RRA volumes (P<0.001). Topologic similarity indexes with 4D-PET were slightly statistically higher with multi-RRA than with 3D-PET (Dice and Jaccard) or 4D-CT (Dice, Jaccard and Overlap). CONCLUSIONS: The tumor volumes delineated on multi-RRA are similar to the volumes obtained with 4D PET, with shorter acquisition time.


Assuntos
Neoplasias Pulmonares , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Fluordesoxiglucose F18 , Tomografia Computadorizada Quadridimensional/métodos , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia por Emissão de Pósitrons/métodos
4.
Haematologica ; 106(1): 154-162, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32079702

RESUMO

The relevance of circulating tumor DNA (ctDNA) analysis as a liquid biopsy and minimal residual disease tool in the management of classical Hodgkin Lymphoma (cHL) patients was demonstrated in retrospective settings and remains to be confirmed in a prospective setting. We developed a targeted Next-Generation sequencing (NGS) panel for fast analysis (AmpliSeq technology) of nine commonly mutated genes in biopies and ctDNA of cHL patients. We then conducted a prospective trial to assess ctDNA follow up at diagnosis and after 2 cycles of chemotherapy (C2). Sixty cHL patients treated by first line conventional chemotherapy (BEACOPPescalated [21.3%], ABVD/ABVD-like [73.5%] and other regimens [5.2%, for elderly patients] were assessed in this non-interventional study. Median age of the patients was 33.5 years (range 20-86). Variants were identified in 42 (70%) patients. Mutations of NFKBIE, TNFAIP3, STAT6, PTPN1, B2M, XPO1, ITPKB, GNA13 and SOCS1 were found in 13.3%, 31.7%, 23.3%, 5%, 33.3%, 10%, 23.3%, 13.3% and 50% of patients, respectively. ctDNA concentration and genotype are correlated with clinical characteristics and presentation. Regarding early therapeutic response, 45 patients (83%, NA=6) had a negative positron emission tomography (PET) after C2 (Deauville Score 1-3). Mean of DeltaSUVmax after C2 was -78.8%. We analyzed ctDNA after C2 for 54 patients (90%). ctDNA became rapidly undetectable in all cases after C2. Variant detection in ctDNA is suitable to depict the genetic features of cHL at diagnosis and may help to assess early treatment response, in association with PET. Clinical Trial reference: NCT02815137.


Assuntos
DNA Tumoral Circulante , Doença de Hodgkin , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais , Bleomicina/uso terapêutico , DNA Tumoral Circulante/genética , Dacarbazina/uso terapêutico , Doxorrubicina/uso terapêutico , Genótipo , Doença de Hodgkin/diagnóstico , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/genética , Humanos , Pessoa de Meia-Idade , Mutação , Estudos Prospectivos , Estudos Retrospectivos , Vimblastina/uso terapêutico , Adulto Jovem
5.
J Clin Pharm Ther ; 45(5): 1114-1119, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32519358

RESUMO

WHAT IS KNOWN AND OBJECTIVES: In Europe, the pharmaceutical supply of chromium-51 has been stopped. However, this isotope is necessary for the evaluation of glomerular filtration rates. It is possible to replace it with technetium-99m, but the validation of this change in the measurement method must be carried out. METHODS: A retrospective analysis of chromium-51 data from January 2018 to January 2019 was performed, followed by a study from January 2019 to January 2020 using the technetium tracer. The patients were different in the both study groups, and none had an eGFR below 50 mL min-1 . A cost analysis was performed. Patient exposure to ionizing radiation was studied for both methods. RESULTS AND DISCUSSION: Seventy-eight patients were included in the study. In total, 42 EDTA-51 Cr and 36 DTPA-99m Tc examinations were conducted and compared. There were no significant differences between the methods used to assess renal function (P = .351). The results of cost analysis and patient radiation exposure were in favour of DTPA-99m Tc examinations. WHAT IS NEW AND CONCLUSION: Within the limitations of a retrospective study of two patient cohorts, there was no significant difference between the results obtained with chromium-51 and technetium-99m tracers. In addition, with the use of DTPA-99m Tc, operating costs and patient exposure to ionizing radiation were reduced, and clinical activity was maintained for the patients' benefit. Radiopharmacists are able to react quickly to supply contingencies, reduce operating costs and maintain the quality of medical examinations.


Assuntos
Taxa de Filtração Glomerular/fisiologia , Rim/diagnóstico por imagem , Farmacêuticos/organização & administração , Serviço de Farmácia Hospitalar/organização & administração , Radioisótopos de Cromo/farmacocinética , Feminino , Humanos , Testes de Função Renal/métodos , Transplante de Rim/métodos , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Papel Profissional , Compostos Radiofarmacêuticos/farmacocinética , Estudos Retrospectivos , Pentetato de Tecnécio Tc 99m/farmacocinética
6.
Am J Perinatol ; 37(7): 754-761, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31121636

RESUMO

OBJECTIVE: This study aimed to identify and validate the diagnostic utility of a set of clinical and laboratory criteria (early warning criteria [EWC]) that portend a clinical deterioration event (escalated care event [ECE]) in neonatal intensive care unit (NICU) patients. STUDY DESIGN: Using the RAND appropriateness method, we first established a consensus on seven ECE, that is, events that require additional monitoring, treatment, or stay in the NICU or that were associated with morbidity. We then established consensus on EWC that could portend an ECE from an initial set of 32 potential EWC items to a final set of 10 items. The occurrence and nonoccurrence of EWC and ECE were prospectively identified and tracked over 9 weeks. RESULTS: Among 170 NICU patients studied (2,502 patient-days), the frequency of an EWC was 53 per 1,000 patient-days. Of these patients, 41% had an EWC and 16% had an ECE. An EWC was followed by an ECE within 72 hours, 37% of the time, and within a median time interval of 113 minutes. The sensitivity, specificity, positive predictive values, and negative predictive values of EWC in identifying an ECE were 0.96, 0.69, 0.37, and 0.99, respectively. CONCLUSION: A simple bedside NICU-specific EWC identifies neonates likely to develop ECEs in the NICU.


Assuntos
Doenças do Recém-Nascido/diagnóstico , Recém-Nascido , Recém-Nascido Prematuro , Monitorização Fisiológica/métodos , Feminino , Humanos , Unidades de Terapia Intensiva Neonatal , Masculino , Projetos Piloto , Estudos Prospectivos , Medição de Risco/métodos , Sensibilidade e Especificidade
7.
J Hand Surg Am ; 45(5): 379-388.e1, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32089378

RESUMO

PURPOSE: Patient knowledge of the frequency with which electrodiagnostic testing (EDx) for suspected median neuropathy at the carpal tunnel addresses nuance in the distinction between normal and abnormal neurophysiology might help them make an informed decision about whether or not to have this test. We reviewed a large set of consecutive EDx for possible carpal tunnel syndrome (CTS) and associated medical records to determine (1) the percentage of EDx measurements within 10% of threshold values; (2) discordance between clinician and EDx diagnosis of CTS using diagnostic performance characteristics; and (3) demographic and disease characteristics independently associated with EDx diagnosis of median neuropathy at the carpal tunnel. METHODS: We retrospectively reviewed nerve conduction study (NCS) results of 537 consecutive patients evaluated for possible idiopathic median neuropathy at the carpal tunnel. We measured the number of patients within 10% of 3 NCS diagnostic thresholds; the diagnostic performance characteristics comparing clinician and EDx diagnosis; and patient and disease characteristics associated with EDx diagnosis of CTS. RESULTS: The 3 NCS parameters were within 10% of the threshold for diagnosis of median neuropathy at the carpal tunnel in 2.6% to 33% of patients. Overall, 76% of EDx results were interpreted as median neuropathy at the carpal tunnel, 19% as normal, and 5% as another diagnosis (eg, cervical radiculopathy). Patients with normal EDx were significantly younger, more likely not to report paresthesias/numbness, more likely to have prior normal EDx, and less likely to have had a previous contralateral carpal tunnel release. CONCLUSIONS: This data set reflecting management strategies for suspected CTS at a large institution confirms inherent diagnostic uncertainty, relatively strong concordance between clinician and EDx diagnosis, and the importance of focusing on paresthesia rather than pain. These findings support the use of clinical prediction rules and may help inform a patient's decision regarding whether or not to have EDx. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic III.


Assuntos
Síndrome do Túnel Carpal , Síndrome do Túnel Carpal/diagnóstico , Humanos , Nervo Mediano , Condução Nervosa , Estudos Retrospectivos , Punho
8.
BMC Fam Pract ; 20(1): 107, 2019 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-31351460

RESUMO

BACKGROUND: The German clinical guideline on tobacco addiction recommends that general practitioners (GPs) provide brief stop-smoking advice to their patients according to the "5A" or the much briefer "ABC" method, but its implementation is insufficient. A lack of training is one barrier for GPs to provide such advice. Moreover, the respective effectiveness of a 5A or ABC training regarding subsequent delivery of stop-smoking advice has not been investigated. We developed a training for GPs according to both methods, and conducted a pilot study with process evaluation to optimize the trainings according to the needs of GPs. This study aims at evaluating the effectiveness of both trainings. METHODS: A pragmatic 2-arm cluster randomised controlled trial with a pre-post data collection will be conducted in 48 GP practices in North Rhine-Westphalia (Germany). GPs will be randomised to receive a 3.5-h-training in delivering either 5A or ABC, including peer coaching and intensive role plays with professional actors. The patient-reported primary outcome (receipt of GP advice to quit: yes/no) and secondary outcomes (recommendation rates of smoking cessation treatments, group comparison (5A versus ABC): receipt of GP advice to quit) will be collected in smoking patients routinely consulting their GP within 4 weeks prior, and 4 weeks following the training. Additional secondary outcomes will be collected at 4, 12 and 26 weeks following the consultation: use of cessation treatments during the last quit attempt (if so) since the GP consultation, and point-prevalence abstinence rates. The primary data analysis will be conducted using a mixed-effects logistic regression model with random effects for the cluster variable. DISCUSSION: If the training increases the rates of delivery of stop-smoking advice, it would offer a low-threshold strategy for the guideline implementation in German primary care. Should one method prove superior, a more specific guideline recommendation can be proposed. TRIAL REGISTRATION: German Clinical Trials Register (DRKS00012786); registered on 22th August 2017, prior to the first patient in.


Assuntos
Clínicos Gerais/educação , Relações Médico-Paciente , Abandono do Hábito de Fumar/métodos , Alemanha , Humanos , Estudos Multicêntricos como Assunto , Projetos Piloto , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa
9.
Hemoglobin ; 43(1): 42-49, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31060394

RESUMO

Nonenzymatic glycation (NEG) of human hemoglobin (Hb A) consists of initial non covalent, reversible steps involving glucose and amino acid residues, which may also involve effector reagent(s) in the formation of labile Hb A1c (the conjugate acid of the Schiff base). Labile Hb A1c can then undergo slow, largely irreversible, formation of stable Hb A1c (the Amadori product). Stable Hb A1c is measured to assess diabetic progression after labile Hb A1c removal. This study aimed to increase the understanding of the distinctions between labile and stable Hb A1c from a mechanistic perspective in the presence of 2,3-bisphosphoglycerate (2,3-BPG). 2,3-Bisphosphoglycerate is an effector reagent that reversibly binds in the Hb A1c pocket and modestly enhances overall NEG rate. The deprotonation of C2 on labile Hb A1c in the formation of the Amadori product was previously proposed to be rate-limiting. Computational chemistry was used here to identify the mechanism(s) by which 2,3-BPG facilitates the deprotonation of C2 on labile Hb A1c. 2,3-Bisphosphoglycerate is capable of abstracting protons on C2 and the α-nitrogen of labile Hb A1c and can also deprotonate water and/or amino acid residues, therefore preparing these secondary reagents to deprotonate labile Hb A1c. Parallel reactions not leading to an Amadori product were found that include formation of the neutral Schiff base, dissociation of glucose from the protein, and cyclic glycosylamine formation. These heretofore under appreciated parallel reactions may help explain both the selective removal of labile from stable Hb A1c and the slow rate of NEG.


Assuntos
2,3-Difosfoglicerato/metabolismo , Hemoglobinas Glicadas/metabolismo , 2,3-Difosfoglicerato/química , Aminoácidos/química , Glucose/química , Glucose/metabolismo , Hemoglobinas Glicadas/química , Glicosilação , Humanos , Ligação Proteica , Multimerização Proteica
10.
Eur J Nucl Med Mol Imaging ; 45(10): 1672-1679, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29705879

RESUMO

INTRODUCTION: Our aim was to study the prognostic value of two new 18F-FDG PET biomarkers in diffuse large B-cell lymphoma (DLBCL). We examined the total tumor surface (TTS), describing the tumor-host interface, and the tumor volume surface ratio (TVSR), corresponding to the ratio between the total metabolic tumor volume (TMTV) and TTS, describing the tumor fragmentation. METHODS: We retrospectively included 215 patients with DLBCL. Patients underwent initial 18F-FDG PET/CT before R-CHOP (73%) or intensified R-CHOP (R-ACVBP) regimens (27%). The TMTV was measured using a fixed threshold value of 41% of SUVmax. To calculate TTS and TVSR, the surface was measured using an in-house software based on the marching cube algorithm. Spearman's rank correlation coefficient (ρ) was computed between TMTV, TTS, and TVSR, and ROC analysis was performed. Survival functions at 5 years were studied using a Kaplan-Meier method and uni/multivariate Cox analysis. RESULTS: TVSR was poorly correlated with TMTV (ρ = 0.5) and TTS (ρ = 0.26), while TTS was highly correlated with TMTV (ρ = 0.94) and was, therefore, excluded from the analysis. TMTV had the highest area under the ROC curve (0.711) and the best sensitivity (0.797), while TVSR had the best specificity (0.745). The optimal cut-off values to predict 5-year OS were 222 cm3 for TMTV and 6.0 mm for TVSR. Patients with high TMTV and TVSR had significantly worse prognosis in Kaplan-Meier and Cox univariate analysis. In a multivariate Cox analysis combining the International Prognostic Index (IPI), the type of chemotherapy, TMTV, and TVSR, all parameters were independent and significant prognostic factors (HR [95%CI]: IPI 1.4 [1.1-1.8], type of chemotherapy 4.5 [2.0-10.5], TMTV 2.8 [1.4-5.5], TVSR 2.1 [1.3-3.4]). A synergistic effect between TMTV and TVSR was observed in a Kaplan-Meier analysis combining the two parameters. CONCLUSIONS: TVSR measured on the initial 18F-FDG PET is an independent prognostic factor in DLBCL and has an additional prognostic value when combined with TMTV, IPI score and chemotherapy.


Assuntos
Fluordesoxiglucose F18 , Linfoma Difuso de Grandes Células B/diagnóstico por imagem , Linfoma Difuso de Grandes Células B/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Carga Tumoral , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Prognóstico , Curva ROC , Estudos Retrospectivos
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