RESUMO
BACKGROUND: Coagulation profiles following major trauma vary depending on injury pattern and degree of shock. The physiologic mechanisms involved in coagulation function at any given time are varied and remain poorly understood. Thromboelastography (TEG) has been used evaluate coagulation profiles in the trauma population with some reports demonstrating a spectrum of fibrinolysis to fibrinolytic shutdown on initial presentation. The objective of this study was to evaluate the fibrinolytic profile of patients with TBI using thromboelastography (TEG). We hypothesized that patients with TBI would demonstrate low fibrinolytic activity. METHODS: All trauma activations at an ACS-verified level 1 trauma center received a TEG analysis upon arrival from December 2019 to June 2021. A retrospective review of the results and outcomes was conducted, and TBI patients were compared to patients without TBI. Linear regression was used to evaluate the effect of patient and injury factors on fibrinolysis. Hyperfibrinolysis was defined as LY30 â> â7.7%, physiologic fibrinolysis as LY30 0.6-7.7%, and fibrinolytic shutdown as LY30 â< â0.6%. RESULTS: A total of 1369 patients received an admission TEG analysis. Patients with TBI had a significantly higher median ISS (16 vs. 8, p â< â0.001), lower median admission Glasgow Coma Scale (14 vs. 15, p â< â0.001), longer intensive care unit length of stay (3 vs. 2 days, p â< â0.0001), increased ventilator days (216 vs. 183, p â< â0.001), higher mortality (14.6% vs. 5.1%, p â< â0.001), but lower shock index (0.6 vs. 0.7, p â< â0.0001) compared to those without TBI. Median LY30 was found to be decreased in the TBI group (0.1 vs. 0.2, p â= â0.0006). Patients with TBI were found to have a higher rate of fibrinolytic shutdown compared those without TBI (68.7% vs. 63.5%, p â= â0.054). ISS, sex, and shock index were found to be predictive of LY30 on linear regression, but TBI was not (Β: 0.09, SE: 0.277, p â= â0.745). The rate of DVT/PE did not appear to be elevated in patients with TBI (0.8%) and without TBI (1.2%). CONCLUSIONS: Trauma patients with and without TBI were found to have high rates of fibrinolytic shutdown. Although there was a high incidence of fibrinolytic shutdown, it did not appear to have an impact on the rate of thrombotic complications. The clinical significance of these results is unclear and differs significantly from recent reports which demonstrated that TBI is associated with a 25% rate of fibrinolytic shutdown. Further investigation is needed to better define the fibrinolytic pathway in patients with trauma and TBI to develop optimal treatment algorithms.
Assuntos
Transtornos da Coagulação Sanguínea , Lesões Encefálicas Traumáticas , Ferimentos e Lesões , Humanos , Transtornos da Coagulação Sanguínea/etiologia , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Fibrinólise/fisiologia , Testes de Coagulação Sanguínea/efeitos adversos , Tromboelastografia/efeitos adversos , Tromboelastografia/métodos , Ferimentos e Lesões/complicaçõesRESUMO
In a structure-function study of sulfatides that typically stimulate type II NKT cells, we made an unexpected discovery. We compared analogs with sphingosine or phytosphingosine chains and 24-carbon acyl chains with 0-1-2 double bonds (C or pC24:0, 24:1, or 24:2). C24:1 and C24:2 sulfatide presented by the CD1d monomer on plastic stimulated type II, not type I, NKT cell hybridomas, as expected. Unexpectedly, when presented by bone marrow-derived DCs (BMDCs), C24:2 reversed specificity to stimulate type I, not type II, NKT cell hybridomas, mimicking the corresponding ß-galactosylceramide (ßGalCer) without sulfate. C24:2 induced IFN-γ-dependent immunoprotection against CT26 colon cancer lung metastases, skewed the cytokine profile, and activated conventional DC subset 1 cells (cDC1s). This was abrogated by blocking lysosomal processing with bafilomycin A1, or by sulfite blocking of arylsulfatase or deletion of this enyzme that cleaves off sulfate. Thus, C24:2 was unexpectedly processed in BMDCs from a type II to a type I NKT cell-stimulating ligand, promoting tumor immunity. We believe this is the first discovery showing that antigen processing of glycosylceramides alters the specificity for the target cell, reversing the glycolipid's function from stimulating type II NKT cells to stimulating type I NKT cells, thereby introducing protective functional activity in cancer. We also believe our study uncovers a new role for antigen processing that does not involve MHC loading but rather alteration of which type of cell is responding.
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Células T Matadoras Naturais , Neoplasias , Humanos , Sulfoglicoesfingolipídeos/metabolismo , Antígenos CD1d/genética , Apresentação de Antígeno , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Sulfatos/metabolismoRESUMO
The human T-lymphotropic virus type 1 (HTLV-1) retrovirus infects 10-20 million people globally, with endemic regions in southwestern Japan, the Caribbean basin, Africa, and central Australia. HTLV-1 is associated with lifelong infection and immune suppression, resulting in a range of serious sequalae, including adult T-cell leukaemia or lymphoma (ATLL) in 5% of cases. To date, there are no preventive or curative treatments for HTLV-1 and treatment outcomes for ATLL remain generally poor. Depending on the disease subtype, overall survival is 8-55 months. Recent advancements in the past decade have identified genetic, molecular, and immunological events occurring throughout the lives of individuals infected with HTLV-1 and of those who progress to ATLL. In addition, updated guidelines for clinical management have been published. With the aim of focusing research efforts on the development of treatments for both HTLV-1 infections and ATLL, we have conceptualised a four-step disease model for HTLV-1-associated ATLL: (1) viral exposure, (2) establishment of chronic infection, (3) cellular transformation and evolution, and (4) disease presentation and management. For each stage we describe the clinical features, molecular and immunological factors involved, potential biomarkers of disease progression, and the therapeutic applicability of individual targets. We also discuss emerging concepts and novel treatment approaches. Our hope is that this model will promote research interest and guide the testing of new treatments for this neglected virus and its associated rare cancer.
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Infecções por HTLV-I , Vírus Linfotrópico T Tipo 1 Humano , Leucemia-Linfoma de Células T do Adulto , Linfoma , Adulto , Humanos , Infecções por HTLV-I/complicações , Progressão da Doença , Linfoma/complicaçõesRESUMO
OBJECTIVE: Primary surgical resection remains the mainstay of management in locally advanced differentiated thyroid cancer. Tyrosine kinase inhibitors have recently shown promising results in patients with recurrent locally advanced differentiated thyroid cancer. This study discussed four patients with locally advanced differentiated thyroid cancer managed with tyrosine kinase inhibitors used prior to surgery in the 'neoadjuvant' setting. METHOD: Prospective data collection through a local thyroid database from February 2016 identified four patients with locally advanced differentiated thyroid cancer unsuitable for primary surgical resection commenced on neoadjuvant tyrosine kinase inhibitor therapy. RESULTS: All cases had T4a disease at presentation. Three cases tolerated tyrosine kinase inhibitor therapy for more than 14 months while the last case failed to tolerate treatment at 1 month. All patients subsequently underwent total thyroidectomy to facilitate adjuvant radioactive iodine treatment. Disease-specific survival remains at 100 per cent currently (range, 29-75 months). CONCLUSION: Neoadjuvant tyrosine kinase inhibitors in locally advanced differentiated thyroid cancer can be effective in reducing primary tumour extent to potentially facilitate a more limited surgical resection for local disease control.
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Adenocarcinoma , Neoplasias da Glândula Tireoide , Humanos , Neoplasias da Glândula Tireoide/cirurgia , Terapia Neoadjuvante , Radioisótopos do IodoRESUMO
PURPOSE: Secretory carcinoma (SC) of the salivary gland, formerly known as mammary analogue secretory carcinoma, is an uncommon and fairly newly described low grade malignant neoplasm of the salivary gland. Given the small number of cases reported in the literature to date, treatment guidelines are scarce. This study aimed to describe the clinical characteristics of SC, discuss prior management strategies, and provide recommendations for future treatment. METHODS: We performed a systematic review of all the cases of SC reported in the literature since it was first recognized in 2010. Using Pubmed, Crossref, and Google Scholar, we identified all articles reporting cases of SC. RESULTS: We identified 657 cases of SC in 109 articles. In addition, we provided 2 new cases, for a total of 659 cases in 110 articles. To our knowledge, this is the largest review of cases of SC in the literature to date. We summarized the clinical characteristics of SC, as well as the nodal status, clinical management, recurrence rate, and death rate. CONCLUSIONS: SC occurs on average in middle age (with a large age range), presents most often initially as localized disease without metastasis, and has a low but not insignificant recurrence rate. Deaths have been reported. The generalized recommendations for treatment of SC are in line with those of other low-grade salivary gland malignancies.
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Neoplasias da Mama , Carcinoma , Carcinoma Secretor Análogo ao Mamário , Neoplasias das Glândulas Salivares , Feminino , Humanos , Pessoa de Meia-Idade , Glândulas SalivaresRESUMO
The importance of teams' and individuals' non-technical skills in reducing adverse events is well-recognised. We undertook a systematic review of the published literature to assess the research undertaken to date on non-technical skills and behaviours within oral and maxillofacial, and head and neck (OMFS-H&N) surgery. The aim was to assess the applicability of published studies to current practice, to look at how these studies could guide future research, and look for areas that could be developed further. The search terms included 'non technical skills', 'nontechnical skills', 'NOTSS', 'non-technical skills for surgeons', 'oral surgery', 'oral maxillofacial surgery', 'OMFS', 'maxillofacial surgery', 'head and neck surgery', 'microsurgery', 'behavioural markers', 'behavioural assessment tool', and 'behavioural ratings system'. Three publications were included, involving 83 participants. Participants consistently achieved the highest scores in the 'situational awareness' category and showed a tendency to achieve lower mean scores in the 'communication and teamwork' and 'decision-making' categories. The majority of research into surgeons' non-technical skills has occurred in simulated environments and not in the genuine environments in which actual surgery is being performed on patients. Research involving 'real' patients has been done in the field of OMFS-H&N and this places the specialty in a stronger position than many other surgical specialties.
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Cirurgia Geral , Especialidades Cirúrgicas , Cirurgiões , Conscientização , Competência Clínica , Comunicação , HumanosRESUMO
Multiple Ras proteins, including N-Ras, depend on a palmitoylation/depalmitoylation cycle to regulate their subcellular trafficking and oncogenicity. General lipase inhibitors such as Palmostatin M (Palm M) block N-Ras depalmitoylation, but lack specificity and target several enzymes displaying depalmitoylase activity. Here, we describe ABD957, a potent and selective covalent inhibitor of the ABHD17 family of depalmitoylases, and show that this compound impairs N-Ras depalmitoylation in human acute myeloid leukemia (AML) cells. ABD957 produced partial effects on N-Ras palmitoylation compared with Palm M, but was much more selective across the proteome, reflecting a plasma membrane-delineated action on dynamically palmitoylated proteins. Finally, ABD957 impaired N-Ras signaling and the growth of NRAS-mutant AML cells in a manner that synergizes with MAP kinase kinase (MEK) inhibition. Our findings uncover a surprisingly restricted role for ABHD17 enzymes as regulators of the N-Ras palmitoylation cycle and suggest that ABHD17 inhibitors may have value as targeted therapies for NRAS-mutant cancers.
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Membrana Celular/metabolismo , Hidrolases/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucemia Promielocítica Aguda/metabolismo , Proteínas ras/metabolismo , Proliferação de Células , Células Cultivadas , Humanos , Leucemia Mieloide Aguda/patologia , Leucemia Promielocítica Aguda/patologia , Lipoilação , Microssomos Hepáticos/química , Microssomos Hepáticos/metabolismo , Estrutura MolecularRESUMO
OBJECTIVES: To assess associations between treatment and recurrence-free survival (RFS) among patients with isolated tumor cells (ITCs) in sentinel lymph nodes (SLN) and otherwise stage I/II endometrioid endometrial cancer (EC). METHODS: A multi-institutional retrospective study of patients with SLN ITCs (<200 cells and < 0.2 mm) was performed. Only patients with otherwise stage I/II EC, endometrioid histology, and no evidence of micro-or macrometastases were included. Univariate and multivariable Cox proportional hazard models were used to evaluate associations between treatment, tumor characteristics, and RFS. RESULTS: 175 patients were included. Median follow up time was 31 months. 39% stage IB and 12% stage II disease. 76 (43%) received no adjuvant therapy or vaginal brachytherapy only (NAT/VBT), 21 (12%) had external beam radiation (EBRT), and 78 (45%) received chemotherapy +/- radiation. Patients who received chemotherapy more often had tumors with deep myoinvasion, lymphovascular space invasion (LVSI), and higher grade. Nine (5.1%) patients recurred; 5 distant, 3 retroperitoneal, and 1 vaginal. Extra-vaginal recurrences were similar in patients with or without chemotherapy (5.2% vs 3.8%, p = 0.68). After controlling for stage, LVSI and grade, chemotherapy and EBRT were not associated with RFS (HR = 0.63, 95%CI 0.11-3.52, and HR = 0.90, 95%CI 0.22-3.61, respectively). Type of lymph node dissection and ITC detection method were not associated with RFS. CONCLUSIONS: Risk of retroperitoneal and/or distant recurrence is low (4.6%) for patients with stage I/II endometrioid EC and ITCs in SLNs regardless of treatment. Our preliminary data suggests that adjuvant therapy may not be significantly associated with RFS. However, longer follow-up time and a larger sample size are needed before definitive recommendations regarding adjuvant therapy for patients with EC and only ITCs in SLN can be made.
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Carcinoma Endometrioide/patologia , Carcinoma Endometrioide/terapia , Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/terapia , Linfonodo Sentinela/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Endometrioide/diagnóstico , Quimiorradioterapia Adjuvante , Intervalo Livre de Doença , Neoplasias do Endométrio/diagnóstico , Feminino , Seguimentos , Humanos , Excisão de Linfonodo , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Resultado do TratamentoRESUMO
INTRODUCTION: Parotid masses causing facial palsy are highly indicative of malignancy. A significant number of cases describing benign parotid disease causing facial palsy have been reported. MATERIALS AND METHODS: We performed a systematic review of the literature to establish the aetiology, clinical features, investigations and management undertaken during these presentations to assess how these factors differed from malignant presentations and to establish an evidence-based algorithm for their management. RESULTS: A total of 85 cases were identified from 78 articles. Cystadenolymphomas were the most common histopathological type (p = 0.034). Mean facial palsy recovery duration in neoplastic aetiology was longer than for infective aetiology (p = 0.033). A significant association existed between uncommon infective organisms and development of facial palsy (p = <0.0001). CONCLUSION: Uncommon benign aetiologies are associated with facial palsy. Investigations and management should be guided by patients' clinical presentations, avoiding excessive treatment. Complete facial palsy recovery rates are high, although not immediate.
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Cistadenoma/diagnóstico , Medicina Baseada em Evidências/métodos , Paralisia Facial/etiologia , Linfoma/diagnóstico , Neoplasias Parotídeas/diagnóstico , Algoritmos , Cistadenoma/complicações , Cistadenoma/patologia , Cistadenoma/terapia , Diagnóstico Diferencial , Paralisia Facial/terapia , Humanos , Linfoma/complicações , Linfoma/patologia , Linfoma/terapia , Glândula Parótida/patologia , Neoplasias Parotídeas/complicações , Neoplasias Parotídeas/patologia , Neoplasias Parotídeas/terapiaRESUMO
BACKGROUND: BRCA1/2 mutation status has increasing relevance for ovarian cancer treatments, making traditional coordination of genetic testing by genetic services unsustainable. Consequently alternative models of genetic testing have been developed to improve testing at the initial diagnosis for all eligible women. METHODS: A training module to enable mainstreamed genetic testing by oncology healthcare professionals was developed by genetic health professionals. Oncology healthcare professionals completed questionnaires before and 12 months post-training to assess perceived skills, competence and barriers to their coordinating genetic testing for women with high-grade non-mucinous epithelial ovarian cancer. Genetic health professionals were surveyed 12 months post-training to assess perceived barriers to implementation of mainstreaming. RESULTS: 185 oncology healthcare professionals were trained in 42 workshops at 35 Australasian hospitals. Of the 273 tests ordered by oncology healthcare professionals post-training, 241 (93.1%) met national testing guidelines. The number of tests ordered by genetic health professionals reduced significantly (z = 45.0, p = 0.008). Oncology healthcare professionals' perceived barriers to mainstreamed testing decreased from baseline to follow-up (t = 2.39, p = 0.023), particularly perceived skills, knowledge and attitudes. However, only 58% reported either 'always' or 'nearly always' having ordered BRCA testing for eligible patients at 12 months, suggesting oncology healthcare professionals' perceived barriers were not systematically addressed through training. CONCLUSIONS: Oncology healthcare professionals have demonstrated a willingness to be involved in the provision of genetic testing in a mainstreaming model. If oncology services are to hold responsibility for coordinating genetic testing, their readiness will require understanding of barriers not addressed by training alone to inform future intervention design.
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Carcinoma Epitelial do Ovário/genética , Testes Genéticos/métodos , Genética/educação , Oncologia/educação , Neoplasias Ovarianas/genética , Adolescente , Adulto , Proteína BRCA1/genética , Proteína BRCA2/genética , Educação Médica Continuada , Feminino , Pessoal de Saúde/educação , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
OBJECTIVES: This study aimed to assess the published literature on non-technical skills in otolaryngology surgery and examine the applicability of any research to others' practice, and to explore how the published literature can identify areas for further development and guide future research. METHODS: A systematic review was conducted using the following key words: 'otolaryngology', 'otorhinolaryngology', 'ENT', 'ENT surgery', 'ear, nose and throat surgery', 'head and neck surgery', 'thyroid surgery', 'parathyroid surgery', 'otology', 'rhinology', 'laryngology' 'skull base surgery', 'airway surgery', 'non-technical skills', 'non technical skills for surgeons', 'NOTSS', 'behavioural markers' and 'behavioural assessment tool'. RESULTS: Three publications were included in the review - 1 randomised, controlled trial and 2 cohort studies - involving 78 participants. All were simulation-based studies involving training otolaryngology surgeons. CONCLUSION: Little research has been undertaken on non-technical skills in otolaryngology. Training surgeons' non-technical skill levels are similar across every tested aspect. The research already performed can guide further studies, particularly amongst non-training otolaryngology surgeons and in both emergency and elective non-simulated environments.
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Anestesistas/normas , Competência Clínica/normas , Internato e Residência , Otolaringologia/normas , Anestesistas/educação , Lista de Checagem , Humanos , Otolaringologia/educaçãoRESUMO
It is estimated that polygenic factors can explain up to 18% of familial breast cancer. Clinical implementation of polygenic testing has begun, with several commercial laboratories now testing. Despite commercial implementation, there is little research investigating how women respond and understand polygenic risk information. This study aimed to explore women's experience receiving their personalised polygenic risk score (PRS) and compare responses of women at different levels of polygenic risk. Eligible participants were affected and unaffected women from families clinically assessed to be at high risk for breast cancer who had received their personalised PRS as part of the Variants in Practice Psychosocial Study (ViPPs). In-depth semi-structured interviews were conducted with 21 women (mean age 53.4 years) up to four weeks after receiving their PRS. Interviews were transcribed verbatim and analysed using thematic analysis. Eleven women received a PRS that was in the top quartile of PRS distribution and 10 in the lowest quartile. Women's lived experience with breast cancer informed how they responded to their PRS, constructed and made sense of breast cancer risk following receipt of their PRS, and integrated this new information into their breast cancer risk management. Regardless of polygenic risk level, all participants demonstrated broad knowledge of concepts related to polygenic information and were able to accurately describe the implications of their PRS. Receiving PRS did not appear to negatively impact women's reported distress levels. Our findings suggest polygenic breast cancer information is well received and understood by women at high-risk for breast cancer.
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Neoplasias da Mama/genética , Neoplasias da Mama/psicologia , Compreensão , Adulto , Idoso , Neoplasias da Mama/terapia , Tomada de Decisões , Feminino , Aconselhamento Genético , Testes Genéticos , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Pessoa de Meia-Idade , Motivação , Intervenção Psicossocial , Pesquisa Qualitativa , Risco , Medição de Risco , IncertezaRESUMO
Antibody-mediated modulation of major histocompatibility complex (MHC) molecules, or MHC class I-like molecules, could constitute an effective immunotherapeutic approach. We describe how single-domain antibodies (VHH), specific for the human MHC class I-like molecule CD1d, can modulate the function of CD1d-restricted T cells and how one VHH (1D12) specifically induced strong type I natural killer T (NKT) cell activation. The crystal structure of the VHH1D12-CD1d(α-GalCer)-NKT T-cell receptor (TCR) complex revealed that VHH1D12 simultaneously contacted CD1d and the type I NKT TCR, thereby stabilizing this interaction through intrinsic bispecificity. This led to greatly enhanced type I NKT cell-mediated antitumor activity in in vitro, including multiple myeloma and acute myeloid leukemia patient-derived bone marrow samples, and in vivo models. Our findings underscore the versatility of VHH molecules in targeting composite epitopes, in this case consisting of a complexed monomorphic antigen-presenting molecule and an invariant TCR, and represent a generalizable antitumor approach.
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Receptores de Antígenos de Linfócitos T , Antígenos CD1d/química , Humanos , Receptores de Antígenos de Linfócitos T/químicaRESUMO
OBJECTIVE: This study examined the indications for prehospital needle thoracostomy (pNT), the need for tube thoracostomy (TT) following pNT, and the outcomes of patients who underwent pNT. METHODS: This study is a retrospective chart review of patients who underwent pNT prior to trauma center arrival. Patients were identified from the trauma registry and a quality improvement (QI) database from 9/2014-9/2018. RESULTS: 59 patients underwent 63 pNTs during the time period. The indication for pNT was "hypotension" in only 5 patients (7.9%). A CT chest was obtained on 51 NT attempts with the catheter in place. In 48 (94.1%) NT attempts, the catheter was not in the pleural space. 44 (69.4%) TTs were placed on admission date. CONCLUSION: In patients undergoing pNT, hypotension was rarely the indication. Additionally, CT identified the catheter within the pleural space in only 3 (5.8%) NT attempts. TT placement was performed in 79.3% of NT attempts.
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Tubos Torácicos , Tratamento de Emergência , Agulhas , Pneumotórax/cirurgia , Toracostomia/instrumentação , Adulto , Feminino , Humanos , Masculino , Estudos Retrospectivos , Centros de Traumatologia , Falha de TratamentoRESUMO
Superimposition of radiographic imaging is used to evaluate patient growth and the effects of surgical and/or orthodontic treatment. The purpose of this study was to compare the outcomes of superimposition between two-dimensional (2D) and three-dimensional (3D) superimpositions. 2D lateral cephalograms were generated from the initial and final cone beam computed tomography scans (CBCT) of 18 patients and superimposed. Both 3D CBCT and 2D CBCT generated lateral cephalograms were oriented to the Frankfort horizontal plane and superimposed according to the American Board of Orthodontics recommendations. Changes in landmark position were quantified from the resulting superimposition outcomes via linear measurements made with Dolphin software. Differences between the two methods were analyzed using paired t-tests. Measurements were repeated twice for 10 randomly selected scans to assess reliability by intra-class correlation coefficient (ICC) analysis. Intra-examiner reliability was high for all measurements (ICC>0.84). Agreement between 2D and 3D superimposition outcomes, as measured by P-values, was low for ANS (P=0.026), B-point (P<0.001), ST Upper lip (P=0.019), U1 tip (P=0.010), and U1 apex (P=0.026). 2D measurements were significantly higher than 3D measurements for ANS, B-point, ST Upper lip, U1 tip, and U1 apex. Findings indicated that both methods of superimposition (2D and 3D) are highly reliable. Statistical differences between 2D and 3D superimposition outcomes were below the threshold of clinical significance.
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Imageamento Tridimensional , Ortodontia , Cefalometria , Tomografia Computadorizada de Feixe Cônico , Humanos , Reprodutibilidade dos TestesRESUMO
Invariant natural killer T cells (iNKT cells) are activated by lipid antigens presented by CD1d, but the pathway leading to lipid antigen presentation remains incompletely characterized. Here we show a whole-genome siRNA screen to elucidate the CD1d presentation pathway. A majority of gene knockdowns that diminish antigen presentation reduced formation of glycolipid-CD1d complexes on the cell surface, including members of the HOPS and ESCRT complexes, genes affecting cytoskeletal rearrangement, and ABC family transporters. We validated the role in vivo for the multidrug resistance protein 1 (Mrp1) in CD1d antigen presentation. Mrp1 deficiency reduces surface clustering of CD1d, which decreased iNKT cell activation. Infected Mrp1 knockout mice show decreased iNKT cell responses to antigens from Streptococcus pneumoniae and were associated with increased mortality. Our results highlight the unique cellular events involved in lipid antigen presentation and show how modification of this pathway can lead to lethal infection.
Assuntos
Apresentação de Antígeno/imunologia , Lipídeos/imunologia , Ativação Linfocitária/imunologia , Células T Matadoras Naturais/imunologia , Streptococcus pneumoniae/imunologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/deficiência , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Antígenos CD1d/imunologia , Linhagem Celular , Endossomos/metabolismo , Redes Reguladoras de Genes , Lisossomos/metabolismo , Macrófagos/metabolismo , Microdomínios da Membrana/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Knockout , RNA Interferente Pequeno/metabolismoRESUMO
In Australia, the USA and many Asian countries the life insurance industry is self-regulated. Individuals must disclose genetic test results known to them in applications for new or updated policies including cover for critical care, income protection and death. There is limited information regarding how underwriting decisions are made for policies with such disclosures. The Australian Financial Services Council (FSC) provided de-identified data collected on applications with genetic test result disclosure from its life insurance member companies 2010-2013 to enable repetition of an independent examination undertaken of applications 1999-2003: age; gender; genetic condition; testing result; decision-maker; and insurance cover. Data was classified as to test result alone or additional other factors relevant to risk and decision. Where necessary, the FSC facilitated clarification by insurers. 345/548 applications related to adult-onset conditions. The genetic test result solely influenced the decision in 165/345 applications: positive (n = 23), negative (n = 139) and pending (n = 3). Detailed analyses of the decisions in each of these result categories are presented with specific details of 11 test cases. Policies with standard decisions were provided for all negative test results with evidence of reassessment of previous non-standard decisions and 20/23 positive results with recognition of risk reduction strategies. Disclosure of positive results for breast/ovarian cancer, Lynch syndrome and hereditary spastic paraplegia, and three pending results, generated non-standard decisions. The examination demonstrates some progress in addressing concerns in regard to utilisation of genetic test information but the self-regulatory system in Australia only goes some way in meeting internationally recommended best practice.
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Testes Genéticos/economia , Seguro de Vida/economia , Austrália , Tomada de Decisões , Testes Genéticos/estatística & dados numéricos , Humanos , Seguro de Vida/estatística & dados numéricosRESUMO
Glycosylceramides that activate CD1d-restricted invariant natural killer T (iNKT) cells have potential therapeutic applications for augmenting immune responses against cancer and infections. Previous studies using mouse models identified sphinganine variants of α-galactosylceramide as promising iNKT cell activators that stimulate cytokine responses with a strongly proinflammatory bias. However, the activities of sphinganine variants in mice have generally not translated well to studies of human iNKT cell responses. Here, we show that strongly proinflammatory and anti-tumor iNKT cell responses were achieved in mice by a variant of α-galactosylceramide that combines a sphinganine base with a hydrocinnamoyl ester on C6â³ of the sugar. Importantly, the activities observed with this variant were largely preserved for human iNKT cell responses. Structural and in silico modeling studies provided a mechanistic basis for these findings and suggested basic principles for capturing useful properties of sphinganine analogs of synthetic iNKT cell activators in the design of immunotherapeutic agents.