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Autoimmune optic papillitis is a rare disorder that causes progressive visual loss, often treated with rituximab (RTX). However, its use is not without risks. Here, we present a 51-year-old man who experienced vision loss because of autoimmune optic papillitis, which was well-controlled with RTX. Four years later, the patient developed abdominal pain and diarrhea and was found to have RTX-induced Crohn's disease (CD). The patient failed treatment with azathioprine, but was subsequently able to achieve clinical and endoscopic remission of his CD with ustekinumab, while continuing RTX therapy for autoimmune optic papillitis. This case report describes the efficacy of the anti-interleukin 12/23 monoclonal antibody in inducing remission of RTX-induced CD.
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Breast cancer is treated with a multidisciplinary approach involving surgical oncology, radiation oncology, and medical oncology. The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Breast Cancer include recommendations for clinical management of patients with carcinoma in situ, invasive breast cancer, Paget's disease, Phyllodes tumor, inflammatory breast cancer, and management of breast cancer during pregnancy. The content featured in this issue focuses on the recommendations for overall management of systemic therapy (preoperative and adjuvant) options for nonmetastatic breast cancer. For the full version of the NCCN Guidelines for Breast Cancer, visit NCCN.org.
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Neoplasias da Mama , Humanos , Neoplasias da Mama/terapia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Feminino , Oncologia/normas , Oncologia/métodos , Terapia Combinada/normasAssuntos
Encefalopatias , Infecções , Criança , Humanos , Índia/epidemiologia , Encefalopatias/epidemiologia , Infecções/epidemiologiaRESUMO
BACKGROUND: Telephone advice lines have been recommended internationally to support around-the-clock care for people living at home with advanced illness. While they undoubtedly support care, there is little evidence about what elements are needed for success. A national picture is needed to understand, improve and standardise service delivery/care. AIM: To explore telephone advice lines for people living at home with advanced illness across the four UK nations, and to construct a practical framework to improve services. DESIGN: A cross-national evaluation of telephone advice lines using structured qualitative interviews. A patient and public involvement workshop was conducted to refine the framework. SETTING/PARTICIPANTS: Professionals with responsibilities for how palliative care services are delivered and/or funded at a local or regional level, were purposively sampled. RESULTS: Seventy-one interviews were conducted, covering 60 geographical areas. Five themes were identified. Availability: Ten advice line models were described. Variation led to confusion about who to call and when. Accessibility, awareness and promotion: It was assumed that patients/carers know who to call out-of-hours, but often they did not. Practicalities: Call handlers skills/expertise varied, which influenced how calls were managed. Possible responses ranged from signposting to organising home visits. Integration/continuity of care: Integration between care providers was limited by electronic medical records access/information sharing. Service structure/commissioning: Sustained funding was often an issue for charitably funded organisations. CONCLUSIONS: Our novel evidence-based practical framework could be transformative for service design/delivery, as it presents key considerations relating to the various elements of advice lines that may impact on the patient/carer experience.
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Cuidadores , Cuidados Paliativos , Pesquisa Qualitativa , Humanos , Cuidadores/psicologia , Reino Unido , Adulto , Serviços de Assistência Domiciliar , Feminino , Linhas Diretas , Masculino , TelefoneRESUMO
Biological organisms are multifaceted, intricate systems where slight perturbations can result in extensive changes in gene expression, protein abundance and/or activity, and metabolic flux. These changes occur at different timescales, spatially across cells of heterogeneous origins, and within single-cells. Hence, multimodal measurements at the smallest biological scales are necessary to capture dynamic changes in heterogeneous biological systems. Of the analytical techniques used to measure biomolecules, mass spectrometry (MS) has proven to be a powerful option due to its sensitivity, robustness, and flexibility with regard to the breadth of biomolecules that can be analyzed. Recently, many studies have coupled MS to other analytical techniques with the goal of measuring multiple modalities from the same single-cell. It is with these concepts in mind that we focus this review on MS-enabled multiomic measurements at single-cell or near-single- cell resolution.
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Espectrometria de Massas , Análise de Célula Única , Análise de Célula Única/métodos , Espectrometria de Massas/métodos , Proteômica/métodos , Humanos , Animais , MultiômicaRESUMO
INTRODUCTION: Being on a waiting list for elective (planned) cardiac surgery can be physically and psychologically challenging for patients. Research suggests that stress associated with waiting for surgery is dependent on different individual and contextual factors. However, most data on patients' experiences of waiting for surgery and preferences for waiting list management derives from non-cardiac clinical populations. The aim of the current study is to explore patients' experiences of being on a waiting list for elective cardiac surgery, and their views on how the waiting experience could be improved in the future. This work will inform the patient management strategy during the waiting period for surgery across the four major hospitals in London directly involved in this study, and potentially beyond by transferring learning to other services. METHODS AND ANALYSIS: This is a mixed-methods study that will collect quantitative and qualitative data using a cross-sectional online survey. Patients who are on waiting lists for elective surgery across four major cardiac surgery departments in London hospitals, and are at least 18 years old, will be invited by their healthcare team via text message or letter to complete the survey. The target sample size of non-randomly selected participants will be 268. Bivariable and multivariable regression models will be used to assess associations between survey items measuring the impact of the cardiac condition on specific life domains (eg, daily activities, social and family relationships, hobbies, sexual life), anxiety and depression symptoms as measured by the Patient Health Questionnaire-4 and survey items evaluating experiences of health services. Data on experience and preferences for improvements to the waiting experience will be analysed with qualitative content analysis using an inductive approach. ETHICS AND DISSEMINATION: This study was reviewed and granted ethical approval by the East of England-East Cambridge Research Ethics Committee. Findings from this study will be disseminated through peer-reviewed journals, a research website and social media and with an online event engaging patients, members of the public, healthcare professionals and other relevant stakeholders. TRIAL REGISTRATION NUMB: NCT05996640.
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Procedimentos Cirúrgicos Cardíacos , Cardiopatias , Adolescente , Humanos , Estudos Transversais , Coração , Preferência do Paciente , AdultoRESUMO
Background: The Human Proteome Project has credibly detected nearly 93% of the roughly 20,000 proteins which are predicted by the human genome. However, the proteome is enigmatic, where alterations in amino acid sequences from polymorphisms and alternative splicing, errors in translation, and post-translational modifications result in a proteome depth estimated at several million unique proteoforms. Recently mass spectrometry has been demonstrated in several landmark efforts mapping the human proteoform landscape in bulk analyses. Herein, we developed an integrated workflow for characterizing proteoforms from human tissue in a spatially resolved manner by coupling laser capture microdissection, nanoliter-scale sample preparation, and mass spectrometry imaging. Results: Using healthy human kidney sections as the case study, we focused our analyses on the major functional tissue units including glomeruli, tubules, and medullary rays. After laser capture microdissection, these isolated functional tissue units were processed with microPOTS (microdroplet processing in one-pot for trace samples) for sensitive top-down proteomics measurement. This provided a quantitative database of 616 proteoforms that was further leveraged as a library for mass spectrometry imaging with near-cellular spatial resolution over the entire section. Notably, several mitochondrial proteoforms were found to be differentially abundant between glomeruli and convoluted tubules, and further spatial contextualization was provided by mass spectrometry imaging confirming unique differences identified by microPOTS, and further expanding the field-of-view for unique distributions such as enhanced abundance of a truncated form (1-74) of ubiquitin within cortical regions. Conclusions: We developed an integrated workflow to directly identify proteoforms and reveal their spatial distributions. Where of the 20 differentially abundant proteoforms identified as discriminate between tubules and glomeruli by microPOTS, the vast majority of tubular proteoforms were of mitochondrial origin (8 of 10) where discriminate proteoforms in glomeruli were primarily hemoglobin subunits (9 of 10). These trends were also identified within ion images demonstrating spatially resolved characterization of proteoforms that has the potential to reshape discovery-based proteomics because the proteoforms are the ultimate effector of cellular functions. Applications of this technology have the potential to unravel etiology and pathophysiology of disease states, informing on biologically active proteoforms, which remodel the proteomic landscape in chronic and acute disorders.
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The treatment of Waldenström macroglobulinemia/lymphoplasmacytic lymphoma (WM/LPL) has evolved to include several new options. The NCCN Guidelines for WM/LPL provide a framework on which to base decisions regarding diagnosis, treatment, assessment of response to treatment, and follow-up of both newly diagnosed and previously treated WM/LPL.
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Linfoma de Células B , Macroglobulinemia de Waldenstrom , Humanos , Macroglobulinemia de Waldenstrom/terapia , Macroglobulinemia de Waldenstrom/tratamento farmacológicoRESUMO
Oncogene-induced replication stress generates endogenous DNA damage that activates cGAS-STING-mediated signalling and tumour suppression1-3. However, the precise mechanism of cGAS activation by endogenous DNA damage remains enigmatic, particularly given that high-affinity histone acidic patch (AP) binding constitutively inhibits cGAS by sterically hindering its activation by double-stranded DNA (dsDNA)4-10. Here we report that the DNA double-strand break sensor MRE11 suppresses mammary tumorigenesis through a pivotal role in regulating cGAS activation. We demonstrate that binding of the MRE11-RAD50-NBN complex to nucleosome fragments is necessary to displace cGAS from acidic-patch-mediated sequestration, which enables its mobilization and activation by dsDNA. MRE11 is therefore essential for cGAS activation in response to oncogenic stress, cytosolic dsDNA and ionizing radiation. Furthermore, MRE11-dependent cGAS activation promotes ZBP1-RIPK3-MLKL-mediated necroptosis, which is essential to suppress oncogenic proliferation and breast tumorigenesis. Notably, downregulation of ZBP1 in human triple-negative breast cancer is associated with increased genome instability, immune suppression and poor patient prognosis. These findings establish MRE11 as a crucial mediator that links DNA damage and cGAS activation, resulting in tumour suppression through ZBP1-dependent necroptosis.
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Transformação Celular Neoplásica , Proteína Homóloga a MRE11 , Nucleossomos , Nucleotidiltransferases , Humanos , Proliferação de Células , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Dano ao DNA , Proteína Homóloga a MRE11/metabolismo , Necroptose , Nucleossomos/metabolismo , Nucleotidiltransferases/metabolismo , Radiação Ionizante , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Instabilidade GenômicaRESUMO
BACKGROUND: Vaccine hesitancy is prevalent among people with IBD, in part due to insufficient evidence regarding comparative safety of vaccines in this population. METHODS: We conducted a nationwide comparative study of postvaccination symptoms among those with IBD and health care workers (HCWs) without IBD. Symptom frequency, severity, and duration were measured. Continuous and categorical data were analyzed using Wilcoxon rank-sum and Fisher's exact test. Regression analysis was used to adjust for confounding variables. RESULTS: We had 2910 and 2746 subjects who completed a survey after dose 1 (D1) and dose 2 (D2) respectively (D1: HCW = 933, IBD = 1977; D2: HCW = 884, IBD = 1862). Mean age was 43 years, 67% were female, and 23% were nonwhite; 73% received BNT162b2 (Pfizer) including almost all HCWs and 60% of IBD patients. Most postvaccine symptoms were mild and lasted ≤2 days after both doses in both groups. Health care workers experienced more postvaccination symptoms overall than IBD patients after each dose (D1: 57% vs 35%, P < .001; D2: 73% vs 50%, P < .001). Gastrointestinal symptoms were noted in IBD more frequently after D1 (5.5% vs 3%, P = .003) but not after D2 (10% vs 13%, P = .07). Inflammatory bowel disease subjects who received mRNA-1273 (Moderna) reported more overall symptoms compared with BNT162b2 (57% vs 46%, P < .001) including gastrointestinal symptoms (12% vs 8%, P = .002) after D2. CONCLUSIONS: People with IBD had fewer postvaccination symptoms following the first 2 doses of SARS-CoV-2 mRNA vaccines than HCWs. Among those with symptoms, most symptoms were mild and of short duration.
Those with inflammatory bowel disease (IBD) reported fewer postvaccination symptoms relative to non-IBD health care workers. Local and systemic symptoms were generally mild and lasted less than 2 days in both populations. The data are reassuring with considerable vaccine hesitancy.
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Vacina BNT162 , COVID-19 , Doenças Inflamatórias Intestinais , Adulto , Feminino , Humanos , Masculino , Vacina BNT162/efeitos adversos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Estudos Prospectivos , Vacinação/efeitos adversosRESUMO
The treatment of relapsed/refractory multiple myeloma (MM) has evolved to include several new options. These include new combinations with second generation proteasome inhibitors (PI); second generation immunomodulators, monoclonal antibodies, CAR T cells, bispecific antibodies, selinexor, venetoclax, and many others. Most patients with MM undergo several cycles of remissions and relapse, and therefore need multiple lines of combination therapies. Selecting treatment options for relapsed/refractory MM requires consideration of resistance status to specific classes, and patient-specific factors such as age and other comorbidities should be considered. The NCCN Guidelines for MM provide a framework on which to base decisions regarding workup, treatment, and follow-up of newly diagnosed and previously treated MM. This manuscript outlines the recommendations from NCCN Guidelines for MM specific to relapsed/refractory disease.
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Mieloma Múltiplo , Humanos , Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Oncologia , Mieloma Múltiplo/terapia , Mieloma Múltiplo/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológicoRESUMO
AIMS: Present study has explored the protective response of dual immunization using two different antigenic entities (i.e. flagellin epitope and cytolethal distending toxin subunit B (CdtB) protein) against lethal challenge of typhoidal serovars in a murine model. MAIN METHODS: In-vitro immunogenicity of flagellin epitope-BSA conjugate and CdtB protein was confirmed using Indirect ELISA of typhoid positive patients' sera. Further, both entities were administered intraperitoneally in mice individually or in combination, followed by lethal challenge of typhoidal Salmonellae. Various parameters were analysed such as bacterial burden, mice survival, histopathological analysis, cytokine analysis and immunophenotyping. Serum samples obtained from the immunized mice were used for passive immunization studies, wherein mice survival and mechanism of action of the generated antibodies was studied. KEY FINDINGS: Active immunization studies using the combination of both entities demonstrated improved mice survival after lethal challenge with typhoidal Salmonellae, reduced bacterial burden in organs, expression of immunophenotypic markers in splenocytes and restored tissue histoarchitecture. When used in combination, the effective doses of both the candidates reduced which may be attributed to multiprong approach used by the immune system to recognize Salmonella. Passive immunization studies further determined the protective efficacy of generated antibodies by different mechanisms such as complement mediated bactericidal action, swarming inhibition and increased phagocytic uptake. SIGNIFICANCE: Present study is the first phase of the proof-of-concept which may prove to be beneficial in developing an effective bi-functional vaccine candidate to render protection against both Vi-positive as well as Vi-negative Salmonella strains.
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Febre Tifoide , Vacinas Tíficas-Paratíficas , Humanos , Animais , Camundongos , Febre Tifoide/prevenção & controle , Flagelina , Epitopos , Imunização , Vacinação , SalmonellaRESUMO
BACKGROUND: Frailty is a condition resulting from a decline in physiological reserves caused by an accumulation of several deficits, which progressively impairs the ability to recover from health adverse events. Following a promising feasibility study, the HomeHealth trial assessed a holistic tailored intervention for older adults with mild frailty to promote independence in their own homes, compared with usual care. We aimed to understand how goal setting worked among older people with mild frailty. METHODS: This study was a process evaluation alongside the HomeHealth randomised trial in older adults with mild frailty. The intervention was delivered at participants' homes, either in person or by telephone or videoconferencing. We carried out semi-structured interviews with older participants who had received the intervention (between three and six appointments), on average 233 days (range 68-465) after their last appointment, purposively sampled according to age, gender, number of sessions attended, adverse events, ethnicity, Index of Multiple Deprivation, Montreal Cognitive Assessment (MoCA) and Barthel scores, research site, and HomeHealth worker. We also conducted interviews with HomeHealth workers who delivered the intervention (n=7). Interviews explored the experience and process of goal setting, benefits and challenges, perceived progress, and behaviour change maintenance after the service had finished. Ethics approval was obtained, and all participants gave informed consent. Interviews were thematically analysed. HomeHealth workers kept formal records of goals set and assessed progress towards goals (0-2 rating scale) during six monthly-sessions, which were descriptively summarised. FINDINGS: 56 interviews were completed between July 15, 2022, and May 18, 2023. Study participants (n=49) had a mean age of 80 years (range 66-94), including 32 (65%) women and 17 (35%) men. Participants self-identified as White (n=42), Asian (n=3), Black (n=2), Mixed (n=1), and other ethnic (n=1) backgrounds. Findings suggested goal setting could be both a challenge and a motivator for older participants with mild frailty. Goal setting worked well when the older person could identify a clear need and set realistic goals linked to functioning, which led to a positive sense of achievement. Challenges occurred when older people were already accessing multiple resources and health services, or where the terminology of "goals" was off-putting due to work or school connotations. Average progress towards goals was 1·15/2. Most participants set goals around improving mobility (or a combination of mobility and another goal type such as socialising), and there was evidence of participants sustaining these behaviour changes after the intervention. INTERPRETATION: Older people with mild frailty can engage well with goal setting to promote independence. The lapse between receiving the intervention and being interviewed limited recall for some participants. However, the acceptability and adherence to the intervention for older people with mild frailty, and their moderate progress towards goals, should encourage further tailored and person-centred practices to promote their independence. FUNDING: National Institute for Health Research (NIHR) Health Technology Assessment.
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Fragilidade , Masculino , Humanos , Feminino , Idoso , Idoso de 80 Anos ou mais , Objetivos , Qualidade de Vida , Análise Custo-BenefícioRESUMO
The NCCN Guidelines for Breast Cancer Screening and Diagnosis provide health care providers with a practical, consistent framework for screening and evaluating a spectrum of clinical presentations and breast lesions. The NCCN Breast Cancer Screening and Diagnosis Panel is composed of a multidisciplinary team of experts in the field, including representation from medical oncology, gynecologic oncology, surgical oncology, internal medicine, family practice, preventive medicine, pathology, diagnostic and interventional radiology, as well as patient advocacy. The NCCN Breast Cancer Screening and Diagnosis Panel meets at least annually to review emerging data and comments from reviewers within their institutions to guide updates to existing recommendations. These NCCN Guidelines Insights summarize the panel's decision-making and discussion surrounding the most recent updates to the guideline's screening recommendations.
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Neoplasias da Mama , Detecção Precoce de Câncer , Humanos , Feminino , Neoplasias da Mama/diagnóstico , Medicina de Família e Comunidade , Pessoal de Saúde , OncologiaRESUMO
BACKGROUND: The World Federation for Medical Education (WFME) defines accreditation as 'certification of the suitability of medical education programs, and of competence in the delivery of medical education.' Accreditation bodies function at national, regional and global levels. In 2015, WFME published quality standards for accreditation of postgraduate medical education (PGME). We compared accreditation of pediatric PGME programs to these standards to understand variability in accreditation and areas for improvement. METHODS: We examined 19 accreditation protocols representing all country income levels and world regions. For each, two raters assessed 36 WFME-defined accreditation sub-areas as present, partially present, or absent. When rating "partially present" or "absent", raters noted the rationale for the rating. Using an inductive approach, authors qualitatively analyzed notes, generating themes in reasons for divergence from the benchmark. RESULTS: A median of 56% (IQR 43-77%) of WFME sub-areas were present in individual protocols; 22% (IQR 15-39%) were partially present; and 8.3% (IQR 5.5-21%) were absent. Inter-rater agreement was 74% (SD 11%). Sub-areas least addressed included number of trainees, educational expertise, and performance of qualified doctors. Qualitative themes of divergence included (1) variation in protocols related to heterogeneity in program structure; (2) limited engagement with stakeholders, especially regarding educational outcomes and community/health system needs; (3) a trainee-centered approach, including equity considerations, was not universal; and (4) less emphasis on quality of education, particularly faculty development in teaching. CONCLUSIONS: Heterogeneity in accreditation can be appropriate, considering cultural or regulatory context. However, we identified broadly applicable areas for improvement: ensuring equitable access to training, taking a trainee-centered approach, emphasizing quality of teaching, and ensuring diverse stakeholder feedback.
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Pediatras , Médicos , Humanos , Criança , Escolaridade , AcreditaçãoRESUMO
Characterization of the oral microbiota profile through various studies has shown an association between the microbiome and oral cancer; however, stage-specific determinants of dynamic changes in microbial communities of oral cancer remain elusive. Additionally, the influence of the intratumoral microbiota on the intratumoral immune system remains largely unexplored. Therefore, this study aims to stratify microbial abundance in the early-onset and subsequent stages of oral cancer and analyze their influence on clinical-pathological and immunological features. The microbiome composition of tissue biopsy samples was identified using 16S rRNA amplicon sequencing, while intratumoral and systemic immune profiling was done with flow cytometry and immunohistochemistry-based analysis. The bacterial composition differed significantly among precancer, early cancer, and late cancer stages with the enrichment of genera Capnocytophaga, Fusobacterium, and Treponema in the cancer group, while Streptococcus and Rothia were enriched in the precancer group. Late cancer stages were significantly associated with Capnocytophaga with high predicting accuracy, while Fusobacterium was associated with early stages of cancer. A dense intermicrobial and microbiome-immune network was observed in the precancer group. At the cellular level, intratumoral immune cell infiltration of B cells and T cells (CD4+ and CD8+) was observed with enrichment of the effector memory phenotype. Naive and effector subsets of tumor-infiltrating lymphocytes (TILs) and related gene expression were found to be distinctly associated with bacterial communities; most importantly, highly abundant bacterial genera of the tumor microenvironment were either negatively correlated or not associated with the effector lymphocytes, which led to the conclusion that the tumor microenvironment favors an immunosuppressive and nonimmunogenic microbiota. IMPORTANCE The gut microbiome has been explored extensively for its importance in the modulation of systemic inflammation and immune response; in contrast, the intratumoral microbiome is less studied for its influence on immunity in cancer. Given the established correlation between intratumoral lymphocyte infiltration and patient survival in cases of solid tumors, it was pertinent to explore the extrinsic factor influencing immune cell infiltration in the tumor. Modulation of intratumoral microbiota could have a beneficial effect on the antitumor immune response. This study stratifies the microbial profile of oral squamous cell carcinoma starting from precancer to late-stage cancer and provides evidence for their immunomodulatory role in the tumor microenvironment. Our results suggest combining microbiome study with immunological signatures of tumors for their prognostic and diagnostic application.
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Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Microbiota , Neoplasias Bucais , Humanos , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço , RNA Ribossômico 16S/genética , Microambiente TumoralRESUMO
High-dimensional single-cell mass spectrometric imaging techniques such as multiplexed ion beam imaging by time-of-flight mass spectrometry (MIBI-TOF), imaging mass cytometry (IMC), and flow cytometry-based CyTOF utilize antibodies conjugated to linear metal-chelating polymers. Here, we report on the synthesis and characterization of a dendrimer-based polymer and its utilization in tissue imaging using MIBI-TOF. We compared the staining performance in FFPE tissue of antibodies for lineage-specific immune proteins (CD20, CD3, CD45, FoxP3) that were conjugated with dendrimer or linear polymer. Staining of serial tissue sections with dendron-conjugated and linear-polymer-conjugated antibodies revealed comparable avidities of dendrons and linear polymers with log2 (ratio of mean positive pixel intensity of staining for linear polymers to dendrons) within the range ±0.25. Interestingly, dendron-conjugated antibodies were observed to have some advantages over linear polymer-conjugated antibodies. For example, tissue staining of a nuclear protein, FoxP3 with dendron-conjugated antibodies showed notably less background staining than that of linear-polymer-conjugated antibodies. Additionally, dendron-conjugated antibodies did not exhibit off-target cytosolic binding in neural tissue typically observed when using linear polymer conjugates. Taken together, this work provides a versatile framework for using third-generation dendron-conjugated antibodies with improved staining over conventional linear polymers.
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Dendrímeros , Polímeros , Polímeros/química , Antracenos , Anticorpos/química , Fatores de Transcrição ForkheadRESUMO
Aziridines are commonly used as reagents for the synthesis of drug substances although they are potentially mutagenic and genotoxic. Therefore, their unambiguous detection is critically important. Unfortunately, tandem mass spectrometry (MS2) based on collision-activated dissociation (CAD), a powerful method used for the identification of many unknown compounds in complex mixtures, does not provide diagnostic fragmentation patterns for ionized aziridines. Therefore, a different mass spectrometry approach based on MS3 experiments is presented here for the identification of the aziridine functionalities. This approach is based on selective gas-phase ion-molecule reactions of protonated analytes with tris(dimethylamino)borane (TDMAB) followed by diagnostic CAD reactions in a modified linear quadrupole ion trap (LQIT) mass spectrometer. TDMAB reacts with protonated aziridines by forming adduct ions that have lost a dimethylamine (DMA) molecule ([M + H + TDMAB - HN(CH3)2]+). CAD on these product ions generated diagnostic fragment ions with m/z-values 25- and 43-units lower than those of the ion-molecule reaction product ions. None of the ion-molecule reaction product ions formed from other, structurally related, protonated analytes produced related fragment ions. Quantum chemical calculations were employed to explore the mechanisms of the observed reactions.
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The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Breast Cancer address all aspects of management for breast cancer. The treatment landscape of metastatic breast cancer is evolving constantly. The therapeutic strategy takes into consideration tumor biology, biomarkers, and other clinical factors. Due to the growing number of treatment options, if one option fails, there is usually another line of therapy available, providing meaningful improvements in survival. This NCCN Guidelines Insights report focuses on recent updates specific to systemic therapy recommendations for patients with stage IV (M1) disease.