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1.
Eur Spine J ; 33(4): 1597-1606, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37606724

RESUMO

PURPOSE: Short-segment minimally invasive percutaneous spinal osteosynthesis has now become one of the treatments of choice to treat thoracolumbar fractures. The question of implant removal once the fracture has healed is still a matter of debate since this procedure can be associated with loss of sagittal correction. Therefore, we analyzed risk factors for kyphosis recurrence after spinal implants removal in patients treated with short-segment minimally invasive percutaneous spinal instrumentation for a thoracolumbar fracture. METHODS: A total of 32 patients who underwent implant removal in percutaneous osteosynthesis for post-traumatic thoracolumbar fracture were enrolled in our study. Patient's medical record, operative report and imaging examinations carried out at the trauma and during the follow-up were analyzed. RESULTS: Every patient experienced fracture union. Vertebral kyphotic angle (VKA) and Cobb angle (CA) improved significantly after stabilization surgery. VKA, CA, upper disk kyphotic angle (UDKA) and lower disk kyphotic angle (LDKA) significantly gradually decreased during follow-up. Traumatic disk injury (p: 0.001), younger age (p: 0.01), canal compromise (p: 0.04) and importance of surgical correction (p < 0.001) were significantly associated with kyphosis recurrence after implant removal. Anterior body augmentation did not affect loss of correction (CA and VKA) during the follow-up period (p: 0.57). CONCLUSION: Despite correction of the fracture after stabilization, we observed a progressive loss of correction over time appearing even before implant removal. Particular attention should be paid to post-traumatic disk damage or canal invasion, to young patients and to surgical overcorrection of the traumatic kyphosis.


Assuntos
Fraturas Ósseas , Cifose , Fraturas da Coluna Vertebral , Humanos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia , Fraturas da Coluna Vertebral/complicações , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/cirurgia , Vértebras Torácicas/lesões , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Vértebras Lombares/lesões , Fraturas Ósseas/complicações , Fixação Interna de Fraturas/efeitos adversos , Fixação Interna de Fraturas/métodos , Cifose/diagnóstico por imagem , Cifose/etiologia , Cifose/cirurgia , Fatores de Risco , Resultado do Tratamento , Estudos Retrospectivos
2.
J Virol ; 94(4)2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-31748390

RESUMO

Measles virus (MeV), like all viruses of the order Mononegavirales, utilizes a complex consisting of genomic RNA, nucleoprotein, the RNA-dependent RNA polymerase, and a polymerase cofactor, the phosphoprotein (P), for transcription and replication. We previously showed that a recombinant MeV that does not express another viral protein, C, has severe transcription and replication deficiencies, including a steeper transcription gradient than the parental virus and generation of defective interfering RNA. This virus is attenuated in vitro and in vivo However, how the C protein operates and whether it is a component of the replication complex remained unclear. Here, we show that C associates with the ribonucleocapsid and forms a complex that can be purified by immunoprecipitation or ultracentrifugation. In the presence of detergent, the C protein is retained on purified ribonucleocapsids less efficiently than the P protein and the polymerase. The C protein is recruited to the ribonucleocapsid through its interaction with the P protein, as shown by immunofluorescence microscopy of cells expressing different combinations of viral proteins and by split luciferase complementation assays. Forty amino-terminal C protein residues are dispensable for the interaction with P, and the carboxyl-terminal half of P is sufficient for the interaction with C. Thus, the C protein, rather than being an "accessory" protein as qualified in textbooks so far, is a ribonucleocapsid-associated protein that interacts with P, thereby increasing replication accuracy and processivity of the polymerase complex.IMPORTANCE Replication of negative-strand RNA viruses relies on two components: a helical ribonucleocapsid and an RNA-dependent RNA polymerase composed of a catalytic subunit, the L protein, and a cofactor, the P protein. We show that the measles virus (MeV) C protein is an additional component of the replication complex. We provide evidence that the C protein is recruited to the ribonucleocapsid by the P protein and map the interacting segments of both C and P proteins. We conclude that the primary function of MeV C is to improve polymerase processivity and accuracy, rather than uniquely to antagonize the type I interferon response. Since most viruses of the Paramyxoviridae family express C proteins, their primary function may be conserved.


Assuntos
Vírus do Sarampo/metabolismo , Nucleoproteínas/genética , Proteínas não Estruturais Virais/metabolismo , Proteínas Virais/genética , Animais , Proteínas de Transporte , Linhagem Celular , Chlorocebus aethiops , Células HEK293 , Células HeLa , Humanos , Sarampo/virologia , Vírus do Sarampo/genética , Proteínas do Nucleocapsídeo , Nucleoproteínas/metabolismo , Fosfoproteínas/metabolismo , Ligação Proteica , RNA Polimerase Dependente de RNA/metabolismo , Células Vero , Proteínas não Estruturais Virais/fisiologia , Proteínas Virais/metabolismo , Ativação Viral/genética , Replicação Viral/genética
3.
Eur J Nucl Med Mol Imaging ; 48(3): 874-882, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32820369

RESUMO

INTRODUCTION: This pilot study evaluated the imaging performance of pretargeted immunological positron emission tomography (immuno-PET) using an anti-carcinoembryonic antigen (CEA) recombinant bispecific monoclonal antibody (BsMAb), TF2 and the [68Ga]Ga-labelled HSG peptide, IMP288, in patients with metastatic colorectal carcinoma (CRC). PATIENTS AND METHODS: Patients requiring diagnostic workup of CRC metastases or in case of elevated CEA for surveillance were prospectively studied. They had to present with elevated CEA serum titre or positive CEA tumour staining by immunohistochemistry of a previous biopsy or surgical specimen. All patients underwent endoscopic ultrasound (EUS), chest-abdominal-pelvic computed tomography (CT), abdominal magnetic resonance imaging (MRI) and positron emission tomography using [18F]fluorodeoxyglucose (FDG-PET). For immuno-PET, patients received intravenously 120 nmol of TF2 followed 30 h later by 150 MBq of [68Ga]Ga-labelled IMP288, both I.V. The gold standard was histology and imaging after 6-month follow-up. RESULTS: Eleven patients were included. No adverse effects were reported after BsMAb and peptide injections. In a per-patient analysis, immuno-PET was positive in 9/11 patients. On a per-lesion analysis, 12 of 14 lesions were positive with immuno-PET. Median SUVmax, MTV and TLG were 7.65 [3.98-13.94, SD 3.37], 8.63 cm3 [1.98-46.64; SD 14.83] and 37.90 cm3 [8.07-127.5; SD 43.47] respectively for immuno-PET lesions. Based on a per-lesion analysis, the sensitivity, specificity, positive-predictive value and negative-predictive value were, respectively, 82%, 25%, 82% and 25% for the combination of EUS/CT/MRI; 76%, 67%, 87% and 33% for FDG-PET; and 88%, 100%, 100% and 67% for immuno-PET. Immuno-PET had an impact on management in 2 patients. CONCLUSION: This pilot study showed that pretargeted immuno-PET using anti-CEA/anti-IMP288 BsMAb and a [68Ga]Ga-labelled hapten was safe and feasible, with promising diagnostic performance. TRIAL REGISTRATION: ClinicalTrials.gov NCT02587247 Registered 27 October 2015.


Assuntos
Neoplasias Colorretais , Radioisótopos de Gálio , Anticorpos Monoclonais , Antígeno Carcinoembrionário , Neoplasias Colorretais/diagnóstico por imagem , Fluordesoxiglucose F18 , Compostos Heterocíclicos com 1 Anel , Humanos , Oligopeptídeos , Projetos Piloto , Tomografia por Emissão de Pósitrons
5.
Hum Fertil (Camb) ; 27(1): 2350758, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38957151

RESUMO

Although the deleterious impact of chemotherapy regimen used to treat women of reproductive age with breast cancer on ovarian reserve has been extensively studied, hardly anything has been reported on the effect of these protocols on theca cell function and ovarian androgen secretion. The aim of this prospective multicentric cohort study was to describe serum levels of total testosterone and androstenedione during chemotherapy and 24-month follow-up in 250 patients <40 years treated for breast cancer. Mean basal levels of androstenedione and total testosterone at diagnosis were 1.68 ng/mL and 0.20 ng/mL respectively. No correlation with age was found. Serum levels of androstenedione and total testosterone rapidly decreased after chemotherapy completion, before slowly increasing and almost returning to basal levels in all patients during 2-year follow-up. In conclusion our study demonstrates a chemotherapy-induced alteration of ovarian thecal function, resulting in a significant decrease in serum androgen levels. This alteration of theca cell function adds to the well-known alteration of granulosa cell function, resulting in a global, but partly transient, ovarian failure in young women treated for breast cancer. These data bring new insight into ovarian physiology and emphasize the need for pre and post-treatment ovarian follow-up. Trial registration: ClinicalTrial.gov identifier NCT01114464.


Assuntos
Androstenodiona , Neoplasias da Mama , Testosterona , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/sangue , Adulto , Androstenodiona/sangue , Estudos Prospectivos , Testosterona/sangue , França , Adulto Jovem , Adolescente , Androgênios/sangue , Antineoplásicos/uso terapêutico
6.
Nature ; 450(7169): 541-4, 2007 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-18033295

RESUMO

Submarine landslides can generate sediment-laden flows whose scale is impressive. Individual flow deposits have been mapped that extend for 1,500 km offshore from northwest Africa. These are the longest run-out sediment density flow deposits yet documented on Earth. This contribution analyses one of these deposits, which contains ten times the mass of sediment transported annually by all of the world's rivers. Understanding how this type of submarine flow evolves is a significant problem, because they are extremely difficult to monitor directly. Previous work has shown how progressive disintegration of landslide blocks can generate debris flow, the deposit of which extends downslope from the original landslide. We provide evidence that submarine flows can produce giant debris flow deposits that start several hundred kilometres from the original landslide, encased within deposits of a more dilute flow type called turbidity current. Very little sediment was deposited across the intervening large expanse of sea floor, where the flow was locally very erosive. Sediment deposition was finally triggered by a remarkably small but abrupt decrease in sea-floor gradient from 0.05 degrees to 0.01 degrees. This debris flow was probably generated by flow transformation from the decelerating turbidity current. The alternative is that non-channelized debris flow left almost no trace of its passage across one hundred kilometres of flat (0.2 degrees to 0.05 degrees) sea floor. Our work shows that initially well-mixed and highly erosive submarine flows can produce extensive debris flow deposits beyond subtle slope breaks located far out in the deep ocean.

7.
Neurochirurgie ; 69(5): 101464, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37393989

RESUMO

PURPOSE: To assess the viability and effectiveness of mono-segmental percutaneous screw fixation in the treatment of unstable type B thoracolumbar fracture due to ankylosing spondylitis. METHODS: We report here all 40 patients treated by mono-segmental screw fixation in this indication, between January 2018 and January 2022, with follow-up at 3 and 9 months. Study variables comprised operating time, length of stay, fusion, stabilization quality, and peri-operative morbidity and mortality. RESULTS: One patient showed early displacement of rods caused by technical error. None of the others showed secondary displacement of rods or screws. Mean age was 73 years (range 18-93), mean hospital stay 4.8 days (range 2-15), mean operative time 52minutes (range 26-95minutes) and mean estimated blood loss 40ml. There were 2 deaths caused by intensive care unit complications. All patients except those in intensive care were verticalized within 24hours after surgery. Parker score was unchanged for each patient before and after surgery and during follow-up. CONCLUSION: Mono-segmental percutaneous screw fixation in the treatment of unstable type B thoracolumbar fracture due to ankylosing spondylitis was safe and effective. This study showed that this surgery reduced length of hospital stay, operative time, blood loss and complications compared to open or extended percutaneous surgery, and allowed fast rehabilitation in this vulnerable population.


Assuntos
Parafusos Pediculares , Fraturas da Coluna Vertebral , Espondilite Anquilosante , Humanos , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Fraturas da Coluna Vertebral/cirurgia , Fraturas da Coluna Vertebral/etiologia , Espondilite Anquilosante/complicações , Espondilite Anquilosante/cirurgia , Fixação Interna de Fraturas/efeitos adversos , Parafusos Pediculares/efeitos adversos , Vértebras Lombares/cirurgia , Vértebras Torácicas/cirurgia , Resultado do Tratamento , Estudos Retrospectivos
8.
PLoS One ; 18(11): e0294262, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38033116

RESUMO

Quantifying neutralising capacity of circulating SARS-COV-2 antibodies is critical in evaluating protective humoral immune responses generated post-infection/post-vaccination. Here we describe a novel medium-throughput flow cytometry-based micro-neutralisation test to evaluate Neutralising Antibody (NAb) responses against live SARS-CoV-2 Wild Type and Variants of Concern (VOC) in convalescent/vaccinated populations. Flow Cytometry-Based Micro-Neutralisation Test (Micro-NT) was performed in 96-well plates using clinical isolates WT-B, WT-B.1.177.18 and/or VOCs Beta and Omicron. Plasma samples (All Ireland Infectious Diseases (AIID) Cohort) were serially diluted (8 points, half-log) from 1:20 and pre-incubated with SARS-CoV-2 (1h, 37°C). Virus-plasma mixture were added onto Vero E6 or Vero E6/TMPRSS2 cells for 18h. Percentage infected cells was analysed by automated flow cytometry following trypsinisation, fixation and SARS-CoV-2 Nucleoprotein intracellular staining. Half-maximal Neutralisation Titres (NT50) were determined using non-linear regression. Our assay was compared to Plaque Reduction Neutralisation Test (PRNT) and validated against the First WHO International Standard for anti-SARS-CoV-2 immunoglobulin. Both Micro-NT and PRNT achieved comparable NT50 values. Further validation showed adequate correlation with PRNT using a panel of secondary standards of clinical convalescent and vaccinated plasma samples. We found the assay to be reproducible through measuring both repeatability and intermediate precision. Screening 190 convalescent samples and 11 COVID-19 naive controls (AIID cohort) we demonstrated that Micro-NT has broad dynamic range differentiating NT50s <1/20 to >1/5000. We could also characterise immune-escape VOC Beta and Omicron BA.5, achieving fold-reductions in neutralising capacity similar to those published. Our flow cytometry-based Micro-NT is a robust and reliable assay to quantify NAb titres, and has been selected as an endpoint in clinical trials.


Assuntos
COVID-19 , Vacinas , Humanos , Citometria de Fluxo , SARS-CoV-2 , Testes de Neutralização , Anticorpos Neutralizantes , Anticorpos Antivirais
10.
Neurochirurgie ; 68(5): 510-517, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35533782

RESUMO

OBJECTIVE: Surgery is an effective treatment for drug-resistant temporal-lobe epilepsy (TLE), but is still underutilized for older patients because of a perceived higher rate of perioperative complications, cognitive decline and worse seizure outcome. METHODS: We retrospectively screened all patients operated on in our institution for drug-resistant TLE between 2007 and 2019. Data of patients aged ≥50 years versus <50 years at surgery were compared. The primary endpoint was freedom from disabling seizure (Engel I) at 2 years postoperatively. RESULTS: In patients aged ≥50 years (n=19), mean age at surgery was 54.9 years and mean disease duration was 36.6 years. At 2 years postoperatively, rates of Engel I seizure outcome were not significantly different between the two groups (73.9% in the <50 years group versus 94.4% in the ≥50 years group). Although surgical complications were significantly (47.4%) in the older patients, neurological deficit was permanent in only 5.3% of cases. At 1 year postoperatively, neuropsychological outcome did not significantly differ between the two groups. CONCLUSIONS: Patients aged ≥50 years had an excellent seizure outcome at 2 years postoperatively. Early postoperative complications were more frequent in patients aged ≥50 years but were mostly transient. Cognitive outcome was similar to that in younger patients. These findings strongly suggest that age ≥50 years should not be an exclusion criterion for resective epilepsy surgery in patients with drug-resistant TLE.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia do Lobo Temporal , Epilepsia Resistente a Medicamentos/psicologia , Epilepsia Resistente a Medicamentos/cirurgia , Epilepsia do Lobo Temporal/cirurgia , Humanos , Estudos Retrospectivos , Convulsões/epidemiologia , Convulsões/cirurgia , Lobo Temporal/cirurgia , Resultado do Tratamento
11.
Science ; 378(6624): 1092-1097, 2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36480631

RESUMO

Programming is a powerful and ubiquitous problem-solving tool. Systems that can assist programmers or even generate programs themselves could make programming more productive and accessible. Recent transformer-based neural network models show impressive code generation abilities yet still perform poorly on more complex tasks requiring problem-solving skills, such as competitive programming problems. Here, we introduce AlphaCode, a system for code generation that achieved an average ranking in the top 54.3% in simulated evaluations on recent programming competitions on the Codeforces platform. AlphaCode solves problems by generating millions of diverse programs using specially trained transformer-based networks and then filtering and clustering those programs to a maximum of just 10 submissions. This result marks the first time an artificial intelligence system has performed competitively in programming competitions.

12.
Sci Rep ; 11(1): 8077, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33850177

RESUMO

Gastrointestinal symptoms are frequent in acute adrenal insufficiency. Although digestive symptoms can significantly reduce quality of life, they are rarely described in patients with treated chronic adrenal insufficiency (CAI). We aimed to characterize digestive symptoms in CAI patients. We used the section pertaining functional bowel disorders of the Rome IV questionnaire. A questionnaire was published on the website of the non-profit patient association "Adrenals" (NPPA of CAI patients) for five months. Information on demographics, characteristics of adrenal insufficiency, digestive symptoms and quality of life was collected. The relatives of CAI patients served as a control group. We analyzed responses of 33 control subjects and 119 patients (68 primary adrenal insufficiency (PAI), 30 secondary adrenal insufficiency (SAI) and 21 congenital adrenal hyperplasia (CAH)). Abdominal pain at least once a week over the past 3 months was reported by 40%, 47% and 33% of patients with PAI, SAI and CAH respectively versus 15% for the controls (p = 0.01). Symptoms were consistent with the Rome IV criteria for irritable bowel syndrome in 27%, 33% and 33% of patients respectively versus 6% for the controls (p < 0.0001). Quality of life was described as poor or very poor in 35%, 57% and 24% of patients respectively versus 5% for the controls (p < 0.0001). In conclusion, digestive symptoms are frequent and incapacitating in CAI patients and similar to symptoms of irritable bowel syndrome in 30% of CAI patients. Assessment and management of digestive symptoms should be considered a priority for physicians treating patients with CAI.


Assuntos
Insuficiência Adrenal , Síndrome do Intestino Irritável , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Inquéritos e Questionários
13.
Eur J Obstet Gynecol Reprod Biol ; 254: 132-137, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32971432

RESUMO

OBJECTIVE: Serum AMH level has been shown to decrease in women treated for breast cancer in several studies. However, whether basal AMH status affects AMH dynamics during chemotherapy remains to be clarified. The objective of this study was to compare serum AMH dynamics in young women with either low, normal or high basal serum AMH level at diagnosis, during and after treatment with chemotherapy for breast cancer. STUDY DESIGN: In this secondary analysis of a prospective cohort study, serum AMH was measured during and after chemotherapy in 239 women of reproductive age diagnosed with breast cancer and treated with chemotherapy. The association between AMH dynamics throughout chemotherapy and during follow-up and basal AMH status, i.e. low AMH (<1 µg/l, <7 pmol/l), normal AMH (1-4.9 µg/l, 7-36 pmol/l) and high AMH (≥5 µg/l, >36 pmol/l), was evaluated. Menses occurrence was also recorded. RESULTS: A total of 21 women had low, 154 had normal and 64 had high basal AMH level. Serum AMH rapidly decreased during chemotherapy in all groups, and its variation during chemotherapy and follow-up was not significantly different between the 3 groups. CONCLUSION: No association was found between AMH variation during chemotherapy and follow-up, and basal AMH level at diagnosis. However, women with high basal AMH levels have significantly higher AMH levels throughout chemotherapy and follow-up than women with normal or low basal AMH levels at diagnosis.


Assuntos
Hormônio Antimülleriano , Neoplasias da Mama , Neoplasias da Mama/tratamento farmacológico , Feminino , Humanos , Estudos Prospectivos , Reprodução
14.
Br J Cancer ; 101(8): 1417-24, 2009 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-19755989

RESUMO

BACKGROUND: The von Hippel-Lindau gene (VHL) alteration, a common event in sporadic clear-cell renal-cell carcinoma (CCRCC), leads to highly vascularised tumours. Vascular endothelial growth factor (VEGF) is the major factor involved in angiogenesis, but the prognostic significance of both VHL inactivation and VEGF expression remain controversial. The aims of this study were to analyse the relationship between VHL genetic and epigenetic alterations, VHL expression and VEGF tumour or plasma expression, and to analyse their respective prognostic value in patients with CCRCC. METHODS: A total of 102 patients with CCRCC were prospectively analysed. Alterations in VHL were determined by sequencing, Multiplex Ligation-dependent Probe Amplification (MLPA) and methylation-specific MLPA. Expression of pVHL and VEGF was determined by immunohistochemistry. Plasma VEGF was measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: VHL mutation, deletion and promoter methylation were identified in 70, 76 and 14 cases, respectively. Overall, at least one VHL-gene alteration occurred in 91 cases (89.2%). Both VEGF tumour and plasma expression appeared to be decreased in case of VHL alteration. Median progression-free survival and CCRCC-specific survival were significantly reduced in patients with wild-type VHL or altered VHL and high VEGF expression, which, therefore, represent two markers of tumour aggressiveness in CCRCC. CONCLUSION: Stratifying CCRCCs according to VHL and VEGF status may help tailor therapeutic strategy.


Assuntos
Carcinoma de Células Renais/genética , Neoplasias Renais/genética , Fator A de Crescimento do Endotélio Vascular/genética , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/patologia , Metilação de DNA , Feminino , Humanos , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Fator A de Crescimento do Endotélio Vascular/sangue
15.
J Cell Biol ; 131(4): 1015-24, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7490279

RESUMO

Expression levels of E-MAP-115, a microtubule-associated protein that stabilizes microtubules, increase with epithelial cell polarization and differentiation (Masson and Kreis, 1993). Although polarizing cells contain significant amounts of this protein, they can still divide and thus all stabilized microtubules must disassemble at the onset of mitosis to allow formation of the dynamic mitotic spindle. We show here that binding of E-MAP-115 to microtubules is regulated by phosphorylation during the cell cycle. Immunolabeling of HeLa cells for E-MAP-115 indicates that the protein is absent from microtubules during early prophase and progressively reassociates with microtubules after late prophase. A fraction of E-MAP-115 from HeLa cells released from a block at the G1/S boundary runs with higher apparent molecular weight on SDS-PAGE, with a peak correlating with the maximal number of cells in early stages of mitosis. E-MAP-115 from nocodazole-arrested mitotic cells, which can be obtained in larger amounts, displays identical modifications and was used for further biochemical characterization. The level of incorporation of 32P into mitotic E-MAP-115 is about 15-fold higher than into the interphase protein. Specific threonine phosphorylation occurs in mitosis, and the amount of phosphate associated with serine also increases. Hyperphosphorylated E-MAP-115 from mitotic cells cannot bind stably to microtubules in vitro. These results suggest that phosphorylation of E-MAP-115 is a prerequisite for increasing the dynamic properties of the interphase microtubules which leads to the assembly of the mitotic spindle at the onset of mitosis. Microtubule-associated proteins are thus most likely key targets for kinases which control changes in microtubule dynamic properties at the G2- to M-phase transition.


Assuntos
Ciclo Celular/fisiologia , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Células HeLa/fisiologia , Humanos , Mitose/fisiologia , Fosforilação , Ligação Proteica/fisiologia , Processamento de Proteína Pós-Traducional
16.
J Cell Biol ; 123(2): 357-71, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8408219

RESUMO

A novel microtubule-associated protein (MAP) of M(r) 115,000 has been identified by screening of a HeLa cell cDNA expression library with an anti-serum raised against microtubule-binding proteins from HeLa cells. Monoclonal and affinity-purified polyclonal antibodies were generated for the further characterization of this MAP. It is different from the microtubule-binding proteins of similar molecular weights, characterized so far, by its nucleotide-insensitive binding to microtubules and different sedimentation behavior. Since it is predominantly expressed in cells of epithelial origin (Caco-2, HeLa, MDCK), and rare (human skin, A72) or not detectable (Vero) in fibroblastic cells, we name it E-MAP-115 (epithelial MAP of 115 kD). In HeLa cells, E-MAP-115 is preferentially associated with subdomains or subsets of perinuclear microtubules. In Caco-2 cells, labeling for E-MAP-115 increases when they polarize and form blisters. The molecular characterization of E-MAP-115 reveals that it is a novel protein with no significant homologies to other known proteins. The secondary structure predicted from its sequence indicates two domains connected by a putative hinge region rich in proline and alanine (PAPA region). E-MAP-115 has two highly charged regions with predicted alpha-helical structure, one basic with a pI of 10.9 in the NH2-terminal domain and one neutral with a pI of 7.6 immediately following the PAPA region in the acidic COOH-terminal half of the molecule. A novel microtubule-binding site has been localized to the basic alpha-helical region in the NH2-terminal domain using in vitro microtubule-binding assays and expression of mutant polypeptides in vivo. Overexpression of this domain of E-MAP-115 by transfection of fibroblasts lacking significant levels of this protein with its cDNA renders microtubules stable to nocodazole. We conclude that E-MAP-115 is a microtubule-stabilizing protein that may play an important role during reorganization of microtubules during polarization and differentiation of epithelial cells.


Assuntos
Proteínas Associadas aos Microtúbulos/análise , Alanina/análise , Sequência de Aminoácidos , Aminoácidos/análise , Animais , Anticorpos Monoclonais , Sequência de Bases , Linhagem Celular , Clonagem Molecular , DNA/análise , DNA/genética , Cães , Células Epiteliais , Epitélio/química , Epitélio/ultraestrutura , Fibroblastos/citologia , Imunofluorescência , Humanos , Immunoblotting , Rim/citologia , Microscopia Eletrônica , Proteínas Associadas aos Microtúbulos/genética , Microtúbulos/química , Microtúbulos/ultraestrutura , Dados de Sequência Molecular , Nocodazol/farmacologia , Testes de Precipitina , Prolina/análise , Análise de Sequência de DNA , Transfecção , Células Vero
17.
Ann Biol Clin (Paris) ; 67(6): 715-9, 2009.
Artigo em Francês | MEDLINE | ID: mdl-19939777

RESUMO

We report the case of a 5-years old child referred to the pediatric clinic due to a prolonged history of recurrent otitis. Initial immunologic investigation was normal but a severe C3 complement deficiency was detected by the absence of beta 2-globulin protein fraction using serum protein capillary electrophoresis. C3 was not detected in serum and total complement haemolytic activity was decreased. His mother and father had half of the C3 normal plasma level and a heterozygous mutation of the C3 gene. The diagnosis of hereditary deficiency of the third complement component (C3) with compound heterozygous mutation of the gene was made. This defect in complement protein C3, described to date in only 20 families in the world, is associated with repeated infections. The child is treated with oracillin with relatively good control of symptoms.


Assuntos
Proteínas Sanguíneas/isolamento & purificação , Complemento C3/deficiência , Complemento C3/genética , Complemento C3/uso terapêutico , Pré-Escolar , Complemento C3/metabolismo , Feminino , Heterozigoto , Humanos , Imunoglobulinas/sangue , Contagem de Leucócitos , Contagem de Linfócitos , Masculino , Mutação , Otite/sangue , Otite/imunologia , Recidiva , Valores de Referência
18.
J Radiol ; 90(11 Pt 1): 1695-702, 2009 Nov.
Artigo em Francês | MEDLINE | ID: mdl-19953057

RESUMO

The purpose of this article is to present a fast and clinically usable technique for quantification of liver steatosis. This technique, based on a triple-echo gradient-echo sequence (in-phase, opposed-phase, in-phase), has recently been validated with excellent correlation and accuracy compared to proton MR spectroscopy. The theoretical principles are reviewed, with emphasis on the need to correct for the T2* decay inherent to the use of in-phase and opposed-phase sequences. T1 decay also is negligible due to the use of a low flip angle (20 degrees). The advantage of this technique is that it can generate a parametric representation (map) of liver steatosis, after fast and simple post-processing, based on measurements from standard images (addition, subtraction, division, multiplication) available on the MR scanning console. This parametric method allows quantification of steatosis in focal lesions. The main limitation of the technique relates to its ambiguity with lipid content over 50%, a phenomenon that does not occur with liver steatosis.


Assuntos
Fígado Gorduroso/patologia , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
19.
Bull Soc Pathol Exot ; 112(1): 14-21, 2019.
Artigo em Francês | MEDLINE | ID: mdl-31225728

RESUMO

We report the attitudes and practices of health care workers involved in the disclosure process to adolescents living with HIV (ALHIV) in a network including West and Central African French-speaking countries, and the experiences of young living with HIV (YLHIV). During a three-day workshop in Abidjan, Côte d'Ivoire, caregivers (doctors, psychologists, social workers) from 19 pediatric HIV treatment sites shared their practices and difficulties, and four YPLHIV their own disclosure experience. Thirty five participants from eight West/Central African countries (Benin, Burkina Faso, Ivory Coast, Cameroon, Mali, Democratic Republic of Congo, Senegal, Togo) contributed: 14 doctors, eight psychologists, six counselors, three social workers. The experience of the centers was variable, but the age at disclosure was late: 34% of 1296 adolescents between 10 and 12 years of age knew their status. The median age at disclosure was 13 years (range: 11-15 years). The practice of the disclosure was often complex, because of multiple factors (fear of the parents of the breaking of the secrecy, lack of communication between professionals). The individual disclosure was the main practice. Four centers practiced HIV disclosure in group sessions to facilitate mirror support, and one used peer-to-peer support. YPLHIV have advocated for an earlier disclosure, from 10 years. In West and Central Africa, the process of HIV disclosure remains complex for parents and caregivers, and occurs too late. The development of a good practice guideline for HIV disclosing adapted to socio-cultural contexts should help to improve this process.


Nous rapportons les attitudes et pratiques des soignants en Afrique francophone concernant l'annonce du statut VIH aux adolescents, et les témoignages de jeunes vivant avec le VIH (jvVIH). Lors d'un atelier de trois jours à Abidjan, Côte d'Ivoire, en novembre 2016, les soignants (médecins, psychologues, travailleurs sociaux) de 19 sites de prise en charge pédiatrique du VIH ont partagé leurs pratiques et difficultés et 4 jvVIH leur vécu de l'annonce. Au total, 35 participants de 8 pays d'Afrique de l'Ouest/centrale (Bénin, Burkina Faso, Côte d'Ivoire, Cameroun, Mali, République démocratique du Congo, Sénégal, Togo) ont contribué : 14 médecins, 8 psychologues, 6 conseillers, 3 travailleurs sociaux. L'expérience des centres était variable, mais l'âge à l'annonce restait tardif : 34 % des 1 296 adolescents âgés entre 10 et 12 ans connaissaient leur statut. L'âge médian à l'annonce était de 13 ans (étendue : 11-15 ans). La pratique de l'annonce s'avérait complexe, en raison de multiples facteurs (crainte des parents de la rupture du secret, manque de communication entre professionnels). L'annonce individuelle était la pratique majoritairement adoptée. Quatre centres pratiquaient une annonce en séances de groupe pour faciliter le soutien en miroir, et un avait recours à l'appui de pairs-adolescents. Les jvVIH ont plaidé pour une annonce plus précoce, dès 10 ans. En Afrique de l'Ouest/centrale francophone, le processus de l'annonce reste complexe pour parents et soignants, et l'annonce trop tardive. L'élaboration d'un guide de bonnes pratiques de l'annonce du VIH, adapté aux contextes socio-culturels devrait permettre d'améliorer ce processus.


Assuntos
Atitude do Pessoal de Saúde , Revelação/normas , Infecções por HIV/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde/psicologia , Adolescente , África Central , África Ocidental , Criança , Humanos
20.
Sci Rep ; 9(1): 6243, 2019 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-31000788

RESUMO

Hepatitis E Virus (HEV) genome encodes three proteins including the ORF2 capsid protein. Recently, we demonstrated that HEV produces three different forms of ORF2: (i) the ORF2i form (infectious ORF2) which is the component of infectious particles, (ii) the secreted ORF2g (glycosylated ORF2) and ORF2c (cleaved ORF2) forms that are not associated with infectious particles, but are the major antigens in HEV-infected patient sera. The ORF2 protein sequence contains three highly conserved potential N-glycosylation sites (N1, N2 and N3). The status and biological relevance of ORF2 N-glycosylation in HEV lifecycle remain to be elucidated. Here, we generated and extensively characterized a series of ORF2 mutants in which the three N-glycosylation sites were mutated individually or in combination. We demonstrated that the ORF2g/c protein is N-glycosylated on N1 and N3 sites but not on the N2 site. We showed that N-glycosylation of ORF2 protein does not play any role in replication and assembly of infectious HEV particles. We found that glycosylated ORF2g/c forms are very stable proteins which are targeted by patient antibodies. We also demonstrated that the ORF2i protein is translocated into the nucleus of infected cells. Hence, our study led to new insights into the molecular mechanisms of ORF2 expression.


Assuntos
Vírus da Hepatite E/patogenicidade , Proteínas Virais/química , Proteínas Virais/metabolismo , Anticorpos Monoclonais/química , Anticorpos Monoclonais/metabolismo , Anticorpos Antivirais/química , Anticorpos Antivirais/metabolismo , Núcleo Celular/metabolismo , Núcleo Celular/virologia , Glicosilação , Vírus da Hepatite E/genética , Vírus da Hepatite E/fisiologia , Interações Hospedeiro-Patógeno , Humanos , Mutação , Sinais Direcionadores de Proteínas , Estabilidade Proteica , Proteínas Virais/genética , Proteínas Virais/imunologia
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