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In this experimental study, we combine drop impact into porous media and onto a single fiber to study drop impact into fiber arrays inspired by mammalian fur coats. In our 3D-printed arrays, we vary the packing density, fiber alignment, strand cross-section, and wettability. Drops impact fibers fixed at both ends, penetrating over short periods of time by momentum and laterally spreading throughout the array. Using image analysis, we measure penetration depth and wetted width into the array. Impact Weber number and intrinsic porosity define penetration, retraction, and rebound regimes. On average, at an impact Weber number of ≈80, staggered fibers reduce penetration by 24% in hydrophilic fibers and 34% in hydrophobic fibers, and the penetration reduction percentage is expected to increase with increasing Weber number. Our results indicate that as density grows toward the density of mammalian pelts, penetration will reach a maximum value independent of drop impact velocity, thereby providing an effective rain barrier. Hydrophilicity at the densities we test, 50-150 strands/cm2, aids fiber array resistance to dynamic penetration by impacting drops through the promotion of lateral drop spreading and inhibition of drop fragmentation. Conversely, hydrophobic fibers best resist low-speed wicking. The fraction of a drop that infiltrates hydrophilic and hydrophobic fibers is nearly identical for a fixed Weber number because lateral spreading restricts the penetration depth into hydrophilic fibers but does not restrict mass infiltration. Above a critical Weber number, the entire drop mass penetrates fiber arrays regardless of strand wettability.
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The frequently encountered macroscopic slime molds of the genus Ceratiomyxa have long been recognized by mycologists and protistologists for hundreds of years. These organisms are amoebozoan amoebae that live and grow inside and on the surface of decaying wood. When conditions are favorable, they form subaerial sporulating structures called fruiting bodies which take on a variety of forms. These forms are typically some arrangement of column and/or branches, but one is uniquely poroid, forming folds instead. Originally, this poroid morphology was designated as its own species. However, it was not always clear what significance fruiting body morphology held in determining species. Currently, Ceratiomyxa fruticulosa var. porioides, the poroid form, is considered a taxonomic variety of Ceratiomyxa fruticulosa based on morphological designation alone. Despite its long history of observation and study, the genus Ceratiomyxa has been paid little molecular attention to alleviate these morphological issues. We have obtained the first transcriptomes of the taxon C. fruticulosa var. porioides and found single gene phylogenetic and multigene phylogenomic support to separate it from C. fruticulosa. This provides molecular evidence that fruiting body morphology does correspond to species level diversity. Therefore, we formally raise Ceratiomyxa porioides to species level.
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Filogenia , Especificidade da Espécie , Transcriptoma , Amebozoários/genética , Amebozoários/classificação , Amebozoários/citologiaRESUMO
Biological soil crusts represent a rich habitat for diverse and complex eukaryotic microbial communities. A unique but extremely common habitat is the urban sidewalk and its cracks that collect detritus. While these habitats are ubiquitous across the globe, little to no work has been conducted to characterize protists found there. Amoeboid protists are major predators of bacteria and other microbial eukaryotes in these microhabitats and therefore play a substantial ecological role. From sidewalk crack soil crusts, we have isolated three naked amoebae with finely tapered subpseudopodia, and a simple life cycle consisting of a trophic amoeba and a cyst stage. Using a holistic approach including light, electron, and fluorescence microscopy as well as phylogenetics using the ribosomal small subunit rRNA gene and phylogenomics using 230 nuclear genes, we find that these amoeboid organisms fail to match any previously described eukaryote genus. However, we determined the amoebae belong to the amoebozoan lineage Variosea based on phylogenetics. The molecular analyses place our isolates in two novel genera forming a grade at the base of the variosean group Protosteliida. These three novel varioseans among two novel genera and species are herein named "Kanabo kenzan" and "Parakanabo toge."
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Amebozoários , Filogenia , Amebozoários/classificação , Amebozoários/genética , Amebozoários/isolamento & purificação , Solo/parasitologia , Ecossistema , DNA de Protozoário/genética , CidadesRESUMO
PhyloFisher is a software package written primarily in Python3 that can be used for the creation, analysis, and visualization of phylogenomic datasets that consist of protein sequences from eukaryotic organisms. Unlike many existing phylogenomic pipelines, PhyloFisher comes with a manually curated database of 240 protein-coding genes, a subset of a previous phylogenetic dataset sampled from 304 eukaryotic taxa. The software package can also utilize a user-created database of eukaryotic proteins, which may be more appropriate for shallow evolutionary questions. PhyloFisher is also equipped with a set of utilities to aid in running routine analyses, such as the prediction of alternative genetic codes, removal of genes and/or taxa based on occupancy/completeness of the dataset, testing for amino acid compositional heterogeneity among sequences, removal of heterotachious and/or fast-evolving sites, removal of fast-evolving taxa, supermatrix creation from randomly resampled genes, and supermatrix creation from nucleotide sequences. © 2024 Wiley Periodicals LLC. Basic Protocol 1: Constructing a phylogenomic dataset Basic Protocol 2: Performing phylogenomic analyses Support Protocol 1: Installing PhyloFisher Support Protocol 2: Creating a custom phylogenomic database.
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Aminoácidos , Evolução Biológica , Filogenia , Sequência de Aminoácidos , CulturaRESUMO
Phylogenomic analyses of hundreds of protein-coding genes aimed at resolving phylogenetic relationships is now a common practice. However, no software currently exists that includes tools for dataset construction and subsequent analysis with diverse validation strategies to assess robustness. Furthermore, there are no publicly available high-quality curated databases designed to assess deep (>100 million years) relationships in the tree of eukaryotes. To address these issues, we developed an easy-to-use software package, PhyloFisher (https://github.com/TheBrownLab/PhyloFisher), written in Python 3. PhyloFisher includes a manually curated database of 240 protein-coding genes from 304 eukaryotic taxa covering known eukaryotic diversity, a novel tool for ortholog selection, and utilities that will perform diverse analyses required by state-of-the-art phylogenomic investigations. Through phylogenetic reconstructions of the tree of eukaryotes and of the Saccharomycetaceae clade of budding yeasts, we demonstrate the utility of the PhyloFisher workflow and the provided starting database to address phylogenetic questions across a large range of evolutionary time points for diverse groups of organisms. We also demonstrate that undetected paralogy can remain in phylogenomic "single-copy orthogroup" datasets constructed using widely accepted methods such as all vs. all BLAST searches followed by Markov Cluster Algorithm (MCL) clustering and application of automated tree pruning algorithms. Finally, we show how the PhyloFisher workflow helps detect inadvertent paralog inclusions, allowing the user to make more informed decisions regarding orthology assignments, leading to a more accurate final dataset.
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Eucariotos/genética , Filogenia , SoftwareRESUMO
Integrins are transmembrane receptors that activate signal transduction pathways upon extracellular matrix binding. The integrin-mediated adhesive complex (IMAC) mediates various cell physiological processes. Although the IMAC was thought to be specific to animals, in the past ten years these complexes were discovered in other lineages of Obazoa, the group containing animals, fungi, and several microbial eukaryotes. Very recently, many genomes and transcriptomes from Amoebozoa (the eukaryotic supergroup sister to Obazoa), other obazoans, orphan protist lineages, and the eukaryotes' closest prokaryotic relatives, have become available. To increase the resolution of where and when IMAC proteins exist and have emerged, we surveyed these newly available genomes and transcriptomes for the presence of IMAC proteins. Our results highlight that many of these proteins appear to have evolved earlier in eukaryote evolution than previously thought and that co-option of this apparently ancient protein complex was key to the emergence of animal-type multicellularity. The role of the IMACs in amoebozoans is unknown, but they play critical adhesive roles in at least some unicellular organisms.
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Adesão Celular , Eucariotos , Integrinas , Amoeba , Animais , Evolução Molecular , Fungos , FilogeniaRESUMO
A high tumour mutational burden (hypermutation) is observed in some gliomas1-5; however, the mechanisms by which hypermutation develops and whether it predicts the response to immunotherapy are poorly understood. Here we comprehensively analyse the molecular determinants of mutational burden and signatures in 10,294 gliomas. We delineate two main pathways to hypermutation: a de novo pathway associated with constitutional defects in DNA polymerase and mismatch repair (MMR) genes, and a more common post-treatment pathway, associated with acquired resistance driven by MMR defects in chemotherapy-sensitive gliomas that recur after treatment with the chemotherapy drug temozolomide. Experimentally, the mutational signature of post-treatment hypermutated gliomas was recapitulated by temozolomide-induced damage in cells with MMR deficiency. MMR-deficient gliomas were characterized by a lack of prominent T cell infiltrates, extensive intratumoral heterogeneity, poor patient survival and a low rate of response to PD-1 blockade. Moreover, although bulk analyses did not detect microsatellite instability in MMR-deficient gliomas, single-cell whole-genome sequencing analysis of post-treatment hypermutated glioma cells identified microsatellite mutations. These results show that chemotherapy can drive the acquisition of hypermutated populations without promoting a response to PD-1 blockade and supports the diagnostic use of mutational burden and signatures in cancer.
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Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Glioma/genética , Glioma/terapia , Mutação , Animais , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/imunologia , Reparo de Erro de Pareamento de DNA/genética , Frequência do Gene , Genoma Humano/efeitos dos fármacos , Genoma Humano/genética , Glioma/imunologia , Humanos , Masculino , Camundongos , Repetições de Microssatélites/efeitos dos fármacos , Repetições de Microssatélites/genética , Mutagênese/efeitos dos fármacos , Mutação/efeitos dos fármacos , Fenótipo , Prognóstico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Análise de Sequência de DNA , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Ex vivo systems that incorporate features of the tumor microenvironment and model the dynamic response to immune checkpoint blockade (ICB) may facilitate efforts in precision immuno-oncology and the development of effective combination therapies. Here, we demonstrate the ability to interrogate ex vivo response to ICB using murine- and patient-derived organotypic tumor spheroids (MDOTS/PDOTS). MDOTS/PDOTS isolated from mouse and human tumors retain autologous lymphoid and myeloid cell populations and respond to ICB in short-term three-dimensional microfluidic culture. Response and resistance to ICB was recapitulated using MDOTS derived from established immunocompetent mouse tumor models. MDOTS profiling demonstrated that TBK1/IKKε inhibition enhanced response to PD-1 blockade, which effectively predicted tumor response in vivo Systematic profiling of secreted cytokines in PDOTS captured key features associated with response and resistance to PD-1 blockade. Thus, MDOTS/PDOTS profiling represents a novel platform to evaluate ICB using established murine models as well as clinically relevant patient specimens.Significance: Resistance to PD-1 blockade remains a challenge for many patients, and biomarkers to guide treatment are lacking. Here, we demonstrate feasibility of ex vivo profiling of PD-1 blockade to interrogate the tumor immune microenvironment, develop therapeutic combinations, and facilitate precision immuno-oncology efforts. Cancer Discov; 8(2); 196-215. ©2017 AACR.See related commentary by Balko and Sosman, p. 143See related article by Deng et al., p. 216This article is highlighted in the In This Issue feature, p. 127.
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Antineoplásicos Imunológicos/farmacologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Animais , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Citocinas/metabolismo , Resistencia a Medicamentos Antineoplásicos , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Imunofenotipagem , Camundongos , Técnicas Analíticas Microfluídicas , Receptor de Morte Celular Programada 1/metabolismo , Esferoides Celulares , Imagem com Lapso de Tempo , Células Tumorais CultivadasRESUMO
OBJECTIVES: Immune checkpoint inhibitors have demonstrated clinical benefit in recurrent, metastatic (R/M) squamous cell carcinoma of the head and neck (SSCHN), but lacking are biomarkers that predict response. We sought to define an inflamed tumor immunophenotype in this R/M SCCHN population and correlate immune metrics with clinical parameters and survival. METHODS: Tumor samples were prospectively acquired from 34 patients to perform multiparametric flow cytometry and multidimensional clustering analysis integrated with next-generation sequencing data, clinical parameters and outcomes. RESULTS: We identified an inflamed subgroup of tumors with prominent CD8+ T cell infiltrates and high PD-1/TIM3 co-expression independent of clinical variables, with improved survival compared with a non-inflamed subgroup (median overall survival 84.0 vs. 13.0months, p=0.004). The non-inflamed subgroup demonstrated low CD8+ T cells, low PD-1/TIM3 co-expression, and higher Tregs. Overall non-synonymous mutational burden did not correlate with response to PD-1 blockade in a subset of patients. CONCLUSION: R/M SCCHN patients with an inflamed tumor immunophenotype demonstrate improved survival. Further prospective studies are needed to validate these findings and explore the use of immunophenotype to guide patient selection for immunotherapeutic approaches.
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Carcinoma de Células Escamosas/imunologia , Neoplasias de Cabeça e Pescoço/imunologia , Imunofenotipagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia , Carcinoma de Células Escamosas de Cabeça e PescoçoRESUMO
PD-L1 immunohistochemical staining does not always predict whether a cancer will respond to treatment with PD-1 inhibitors. We sought to characterize immune cell infiltrates and the expression of T-cell inhibitor markers in PD-L1-positive and PD-L1-negative malignant pleural mesothelioma samples. We developed a method for immune cell phenotyping using flow cytometry on solid tumors that have been dissociated into single-cell suspensions and applied this technique to analyze 43 resected malignant pleural mesothelioma specimens. Compared with PD-L1-negative tumors, PD-L1-positive tumors had significantly more infiltrating CD45+ immune cells, a significantly higher proportion of infiltrating CD3+ T cells, and a significantly higher percentage of CD3+ cells displaying the activated HLA-DR+/CD38+ phenotype. PD-L1-positive tumors also had a significantly higher proportion of proliferating CD8+ T cells, a higher fraction of FOXP3+/CD4+ Tregs, and increased expression of PD-1 and TIM-3 on CD4+ and CD8+ T cells. Double-positive PD-1+/TIM-3+ CD8+ T cells were more commonly found on PD-L1-positive tumors. Compared with epithelioid tumors, sarcomatoid and biphasic mesothelioma samples were significantly more likely to be PD-L1 positive and showed more infiltration with CD3+ T cells and PD-1+/TIM-3+ CD8+ T cells. Immunologic phenotypes in mesothelioma differ based on PD-L1 status and histologic subtype. Successful incorporation of comprehensive immune profiling by flow cytometry into prospective clinical trials could refine our ability to predict which patients will respond to specific immune checkpoint blockade strategies. Cancer Immunol Res; 4(12); 1038-48. ©2016 AACR.
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Antígeno B7-H1/imunologia , Mesotelioma/imunologia , Neoplasias Pleurais/imunologia , Linfócitos T Citotóxicos/imunologia , Feminino , Humanos , MasculinoRESUMO
BACKGROUND. Immune checkpoint blockade improves survival in a subset of patients with non-small-cell lung cancer (NSCLC), but robust biomarkers that predict response to PD-1 pathway inhibitors are lacking. Furthermore, our understanding of the diversity of the NSCLC tumor immune microenvironment remains limited. METHODS. We performed comprehensive flow cytometric immunoprofiling on both tumor and immune cells from 51 NSCLCs and integrated this analysis with clinical and histopathologic characteristics, next-generation sequencing, mRNA expression, and PD-L1 immunohistochemistry (IHC). RESULTS. Cytometric profiling identified an immunologically "hot" cluster with abundant CD8+ T cells expressing high levels of PD-1 and TIM-3 and an immunologically "cold" cluster with lower relative abundance of CD8+ T cells and expression of inhibitory markers. The "hot" cluster was highly enriched for expression of genes associated with T cell trafficking and cytotoxic function and high PD-L1 expression by IHC. There was no correlation between immunophenotype and KRAS or EGFR mutation, or patient smoking history, but we did observe an enrichment of squamous subtype and tumors with higher mutation burden in the "hot" cluster. Additionally, approximately 20% of cases had high B cell infiltrates with a subset producing IL-10. CONCLUSIONS. Our results support the use of immune-based metrics to study response and resistance to immunotherapy in lung cancer. FUNDING. The Robert A. and Renée E. Belfer Family Foundation, Expect Miracles Foundation, Starr Cancer Consortium, Stand Up to Cancer Foundation, Conquer Cancer Foundation, International Association for the Study of Lung Cancer, National Cancer Institute (R01 CA205150), and the Damon Runyon Cancer Research Foundation.
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Carcinoma Pulmonar de Células não Pequenas/classificação , Imunofenotipagem , Neoplasias Pulmonares/classificação , Antígeno B7-H1/imunologia , Biomarcadores Tumorais/imunologia , Linfócitos T CD8-Positivos/imunologia , Humanos , Imuno-Histoquímica , Pulmão , MutaçãoRESUMO
With the emergence of checkpoint blockade and other immunotherapeutic drugs, and the growing adoption of smaller, more flexible adaptive clinical trial designs, there is an unmet need to develop diagnostics that can rapidly immunophenotype patient tumors. The ability to longitudinally profile the tumor immune infiltrate in response to immunotherapy also presents a window of opportunity to illuminate mechanisms of resistance. We have developed a fine needle aspirate biopsy (FNA) platform to perform immune profiling on thoracic malignancies. Matching peripheral blood, bulk resected tumor, and FNA were analyzed from 13 mesothelioma patients. FNA samples yielded greater numbers of viable cells when compared to core needle biopsies. Cell numbers were adequate to perform flow cytometric analyses on T cell lineage, T cell activation and inhibitory receptor expression, and myeloid immunosuppressive checkpoint markers. FNA samples were representative of the tumor as a whole as assessed by head-to-head comparison to single cell suspensions of dissociated whole tumor. Parallel analysis of matched patient blood enabled us to establish quality assurance criteria to determine the accuracy of FNA procedures to sample tumor tissue. FNA biopsies provide a diagnostic to rapidly phenotype the tumor immune microenvironment that may be of great relevance to clinical trials.
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Citometria de Fluxo , Tolerância Imunológica , Mesotelioma , Linfócitos T , Neoplasias Torácicas , Microambiente Tumoral/imunologia , Biópsia por Agulha Fina , Feminino , Humanos , Masculino , Mesotelioma/diagnóstico , Mesotelioma/imunologia , Mesotelioma/patologia , Linfócitos T/imunologia , Linfócitos T/patologia , Neoplasias Torácicas/diagnóstico , Neoplasias Torácicas/imunologia , Neoplasias Torácicas/patologiaRESUMO
Despite compelling antitumour activity of antibodies targeting the programmed death 1 (PD-1): programmed death ligand 1 (PD-L1) immune checkpoint in lung cancer, resistance to these therapies has increasingly been observed. In this study, to elucidate mechanisms of adaptive resistance, we analyse the tumour immune microenvironment in the context of anti-PD-1 therapy in two fully immunocompetent mouse models of lung adenocarcinoma. In tumours progressing following response to anti-PD-1 therapy, we observe upregulation of alternative immune checkpoints, notably T-cell immunoglobulin mucin-3 (TIM-3), in PD-1 antibody bound T cells and demonstrate a survival advantage with addition of a TIM-3 blocking antibody following failure of PD-1 blockade. Two patients who developed adaptive resistance to anti-PD-1 treatment also show a similar TIM-3 upregulation in blocking antibody-bound T cells at treatment failure. These data suggest that upregulation of TIM-3 and other immune checkpoints may be targetable biomarkers associated with adaptive resistance to PD-1 blockade.
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Imunidade Adaptativa , Neoplasias Pulmonares/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Idoso , Animais , Antígeno B7-H1/administração & dosagem , Antígeno B7-H1/imunologia , Receptor Celular 2 do Vírus da Hepatite A , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Masculino , Camundongos , Pessoa de Meia-Idade , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , Receptores Virais/genética , Receptores Virais/imunologiaRESUMO
BACKGROUND: Surveying patients is increasingly important for evaluating and improving health care delivery, but practical survey strategies during routine care activities have not been available. OBJECTIVE: We examined the feasibility of conducting routine patient surveys in a primary care clinic using commercially available technology (Web-based survey creation, deployment on tablet computers, cloud-based management of survey data) to expedite and enhance several steps in data collection and management for rapid quality improvement cycles. METHODS: We used a Web-based data management tool (survey creation, deployment on tablet computers, real-time data accumulation and display of survey results) to conduct four patient surveys during routine clinic sessions over a one-month period. Each survey consisted of three questions and focused on a specific patient care domain (dental care, waiting room experience, care access/continuity, Internet connectivity). RESULTS: Of the 727 available patients during clinic survey days, 316 patients (43.4%) attempted the survey, and 293 (40.3%) completed the survey. For the four 3-question surveys, the average time per survey was overall 40.4 seconds, with a range of 5.4 to 20.3 seconds for individual questions. Yes/No questions took less time than multiple choice questions (average 9.6 seconds versus 14.0). Average response time showed no clear pattern by order of questions or by proctor strategy, but monotonically increased with number of words in the question (<20 words, 21-30 words, >30 words)-8.0, 11.8, 16.8, seconds, respectively. CONCLUSIONS: This technology-enabled data management system helped capture patient opinions, accelerate turnaround of survey data, with minimal impact on a busy primary care clinic. This new model of patient survey data management is feasible and sustainable in a busy office setting, supports and engages clinicians in the quality improvement process, and harmonizes with the vision of a learning health care system.
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CONTEXT: Nationally, African Americans are underrepresented in community blood donation programs. To increase blood donation by African Americans, differences between motivators and barriers to blood donation between races should be investigated. OBJECTIVE: To investigate motivators and barriers to blood donation in African American and white blood donors. DESIGN: An 18-item, anonymous, self-administered questionnaire regarding demographics and motivators and barriers to donation was completed by blood donors at a predominately African American and a predominately white fixed donation site. RESULTS: A total of 599 participants (20% African American, 75% white, and 5% other) completed the survey. The most commonly reported reasons to donate included: "because it is the right thing to do" (45% African Americans and 62% white) and "because I want to help save a life" (63% African Americans and 47% white). Unpleasant experiences did not differ as a barrier to continue donation between African Americans and whites. African Americans placed more importance on donating blood to someone with sickle cell disease, convenience of blood donation, treatment of donor center staff, and level of privacy during the screening process. CONCLUSIONS: These data suggest that in a large metropolitan area, reasons for donation among African American and white donors differ. To retain and increase donation frequency of African American donors, these factors should be considered in creating an African American donor recruitment and retention program.
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Atitude Frente a Saúde/etnologia , Negro ou Afro-Americano/psicologia , Doadores de Sangue/psicologia , Motivação , População Branca/psicologia , Adulto , Altruísmo , Asiático/psicologia , Barreiras de Comunicação , Tomada de Decisões , Feminino , Hispânico ou Latino/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: To determine whether glycemic control can be safely achieved with use of a simplified insulin infusion protocol in hospitalized patients who are not in the intensive care unit (ICU). METHODS: We developed a novel intravenous insulin protocol specifically designed for use in the non-ICU setting. We then collected clinical data on the first 30 patients treated with use of this protocol. Our study focused on safety and glycemic control. RESULTS: The insulin infusion protocol was used in 30 patients for a total of 634 hours. A single hypoglycemic episode (glucose level <60 mg/dL) occurred in 3 patients. The target mean glucose level of <150 mg/dL was achieved in 9 hours. Once the glucose target had been achieved, the mean and median glucose concentrations were 156 mg/dL and 140 mg/dL, respectively. CONCLUSION: Use of a simple intravenous insulin protocol can safely and effectively control the blood glucose level in patients in a non-ICU setting.
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Diabetes Mellitus/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Adulto , Idoso , Glicemia/efeitos dos fármacos , Estudos de Coortes , Feminino , Humanos , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/farmacologia , Infusões Intravenosas/métodos , Insulina/efeitos adversos , Insulina/farmacologia , Masculino , Pessoa de Meia-IdadeRESUMO
PURPOSE: The purpose of this investigation was to evaluate and compare the mechanical and thermal properties of 6 commonly used polymethyl methacrylate denture base resins. MATERIALS AND METHODS: Sorption, solubility, color stability, adaptation, flexural stiffness, and hardness were assessed to determine compliance with ADA Specification No. 12. Thermal assessments were performed using differential scanning calorimetry and dynamic mechanical analysis. Results were assessed using statistical and observational analyses. RESULTS: All materials satisfied ADA requirements for sorption, solubility, and color stability. Adaptation testing indicated that microwave-activated systems provided better adaptation to associated casts than conventional heat-activated resins. According to flexural testing results, microwaveable resins were relatively stiff, while rubber-modified resins were more flexible. Differential scanning calorimetry indicated that microwave-activated systems were more completely polymerized than conventional heat-activated materials. CONCLUSION: The microwaveable resins displayed better adaptation, greater stiffness, and greater surface hardness than other denture base resins included in this investigation. Elastomeric toughening agents yielded decreased stiffness, decreased surface hardness, and decreased glass transition temperatures.
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Bases de Dentadura , Polimetil Metacrilato/química , Adsorção , Análise de Variância , Varredura Diferencial de Calorimetria , Cor , Dureza , Temperatura Alta , Humanos , Teste de Materiais , Micro-Ondas , Maleabilidade , Solubilidade , Estresse Mecânico , Propriedades de Superfície , TermodinâmicaRESUMO
Previous studies, mostly in European populations, found sex differences in the pattern of deciduous tooth emergence. Most studies find that the anterior dentition in males is precocial relative to the female dentition, and the pattern reverses so that females lead males in the emergence of the posterior deciduous dentition. Less is known about sex differences in the dental development and emergence of non-European populations. Here we examine the pattern of sex differences in deciduous tooth emergence in Japanese, Javanese, Guatemalan, and Bangladeshi children. The data come from four longitudinal or mixed longitudinal studies using similar study protocols. Survival analysis was used to estimate parameters of a log-normal distribution of emergence for each of the 10 teeth of the left dentition, and sexual dimorphism was assessed by sex-specific differences in mean emergence times and by Bennett's index. The results support the pattern of developmental cross-over observed in other populations. We conclude that there is little evidence to support the hypothesis of Tanguay et al. ([1984] J. Dent. Res. 63:65-68) that ethnic factors mediate sex differences in the emergence of deciduous teeth.
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Caracteres Sexuais , Erupção Dentária/fisiologia , Dente Decíduo/crescimento & desenvolvimento , Bangladesh , Pré-Escolar , Inquéritos de Saúde Bucal , Feminino , Guatemala , Humanos , Indonésia , Lactente , Recém-Nascido , Japão , Estudos Longitudinais , MasculinoRESUMO
OBJECTIVE: To report an unusual case of primary central nervous system non-Hodgkin's lymphoma in which the initial manifestation was panhypopituitarism. METHODS: We present a retrospective case review and discuss similar cases from the literature. RESULTS: A 64-year-old woman with nausea, vomiting, diarrhea, and peripheral and periorbital edema was found to have panhypopituitarism. Magnetic resonance imaging showed minimal enlargement of the pituitary, and a transsphenoidal biopsy of the pituitary was nondiagnostic. Months later, abnormalities of extraocular movements developed. Repeated imaging and a second transsphe-noidal biopsy did not reveal the ultimate diagnosis. When further neurologic signs and symptoms subsequently developed, a right temporal open craniotomy was performed. It was not until this procedure, the patient's third biopsy, that the cause of her illness was discovered to be diffuse large cell lymphoma. CONCLUSION: Although idiopathic panhypopituitarism is a relatively common clinical entity, it remains a diagnosis of exclusion. The development of associated neurologic signs should prompt the clinician to initiate a new search for an underlying cause. This case underscores the protean manifestations of central nervous system lymphoma, both endocrine and neurologic, and the difficulties that may be encountered in attempts to establish a diagnosis.