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1.
Biomacromolecules ; 25(6): 3325-3334, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38775494

RESUMO

Molecules that inhibit the growth of ice crystals are highly desirable for applications in building materials, foods, and agriculture. Antifreezes are particularly essential in biomedicine for tissue banking, yet molecules currently in use have known toxic effects. Antifreeze glycoproteins have evolved naturally in polar fish species living in subzero climates, but practical issues with collection and purification have limited their commercial use. Here, we present a synthetic strategy using polymerization of amino acid N-carboxyanhydrides to produce polypeptide mimics of these potent natural antifreeze proteins. We investigated a set of mimics with varied structural properties and identified a glycopolypeptide with potent ice recrystallization inhibition properties. We optimized for molecular weight, characterized their conformations, and verified their cytocompatibility in a human cell line. Overall, we present a material that will have broad applications as a biocompatible antifreeze.


Assuntos
Proteínas Anticongelantes , Proteínas Anticongelantes/química , Humanos , Glicosilação , Animais , Gelo , Cristalização , Linhagem Celular , Glicopeptídeos/química , Glicopeptídeos/farmacologia
2.
Sensors (Basel) ; 22(16)2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-36016034

RESUMO

Competitive indoor climbing has increased in popularity at the youth, collegiate, and Olympic levels. A critical aspect for improving performance is characterizing the physiologic response to different climbing strategies (e.g., work/rest patterns, pacing) and techniques (e.g., body position and movement) relative to location on climbing wall with spatially varying characteristics (e.g., wall inclinations, position of foot/hand holds). However, this response is not well understood due to the limited capabilities of climbing-specific measurement and assessment tools. In this study, we developed a novel method to examine time-resolved sensor-based measurements of multiple personal biometrics at different microlocations (finely spaced positions; MLs) along a climbing route. For the ML-specific biometric system (MLBS), we integrated continuous data from wearable biometric sensors and smartphone-based video during climbing, with a customized visualization and analysis system to determine three physiologic parameters (heart rate, breathing rate, ventilation rate) and one body movement parameter (hip acceleration), which are automatically time-matched to the corresponding video frame to determine ML-specific biometrics. Key features include: (1) biometric sensors that are seamlessly embedded in the fabric of an athletic compression shirt, and do not interfere with climbing performance, (2) climbing video, and (3) an interactive graphical user interface to rapidly visualize and analyze the time-matched biometrics and climbing video, determine timing sequence between the biometrics at key events, and calculate summary statistics. To demonstrate the capabilities of MLBS, we examined the relationship between changes in ML-specific climbing characteristics and changes in the physiologic parameters. Our study demonstrates the ability of MLBS to determine multiple time-resolved biometrics at different MLs, in support of developing and assessing different climbing strategies and training methods to help improve performance.


Assuntos
Esportes , Dispositivos Eletrônicos Vestíveis , Adolescente , Biometria , Humanos , Movimento/fisiologia , Postura , Esportes/fisiologia
3.
Ther Adv Med Oncol ; 14: 17588359221107113, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35860837

RESUMO

Purpose: Adoptively transferred, ex vivo expanded multi-antigen-targeted T cells (multiTAA-T) represent a new, potentially effective, and nontoxic therapeutic approach for patients with breast cancer (BC). In this first-in-human trial, we investigated the safety and clinical effects of administering multiTAA T cells targeting the tumor-expressed antigens, Survivin, NY-ESO-1, MAGE-A4, SSX2, and PRAME, to patients with relapsed/refractory/metastatic BC. Materials and methods: MultiTAA T-cell products were generated from the peripheral blood of heavily pre-treated patients with metastatic or locally recurrent unresectable BC of all subtypes and infused at a fixed dose level of 2 × 107/m2. Patients received two infusions of cells 4 weeks apart and safety and clinical activity were determined. Cells were administered in an outpatient setting and without prior lymphodepleting chemotherapy. Results: All patients had estrogen receptor/progesterone receptor positive BC, with one patient also having human epidermal growth factor receptor 2-positive. There were no treatment-related toxicities and the infusions were well tolerated. Of the 10 heavily pre-treated patients enrolled and infused with multiTAA T cells, nine had disease progression while one patient with 10 lines of prior therapies experienced prolonged (5 months) disease stabilization that was associated with the in vivo expansion and persistence of T cells directed against the targeted antigens. Furthermore, antigen spreading and the endogenous activation of T cells directed against a spectrum of non-targeted tumor antigens were observed in 7/10 patients post-multiTAA infusion. Conclusion: MultiTAA T cells were well tolerated and induced disease stabilization in a patient with refractory BC. This was associated with in vivo T-cell expansion, persistence, and antigen spreading. Future directions of this approach may include additional strategies to enhance the therapeutic benefit of multiTAA T cells in patients with BC.

4.
Clin Cancer Res ; 26(3): 738-745, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31653641

RESUMO

PURPOSE: Tumor-infiltrating lymphocytes (TIL) are associated with benefit to trastuzumab and chemotherapy in patients with early-stage HER2+ breast cancer. The predictive value of TILs, TIL subsets, and other immune cells in patients receiving chemotherapy-sparing lapatinib plus trastuzumab treatment is unclear.Experimental Design: Hematoxylin and eosin-stained slides (n = 59) were used to score stromal (s-)TILs from pretreatment biopsies of patients enrolled in the neoadjuvant TBCRC006 trial of 12-week lapatinib plus trastuzumab therapy (plus endocrine therapy for ER+ tumors). A 60% threshold was used to define lymphocyte-predominant breast cancer (LPBC). Multiplexed immunofluorescence (m-IF) staining (CD4, CD8, CD20, CD68, and FoxP3) and multispectral imaging were performed to characterize immune infiltrates in single formalin-fixed paraffin-embedded slides (n = 33). RESULTS: The pathologic complete response (pCR) rate was numerically higher in patients with LPBC compared with patients with non-LPBC (50% vs. 19%, P = 0.057). Unsupervised hierarchical clustering of the five immune markers identified two patient clusters with different responses to lapatinib plus trastuzumab treatment (pCR = 7% vs. 50%, for cluster 1 vs. 2 respectively; P = 0.01). In multivariable analysis, cluster 2, characterized by high CD4+, CD8+, CD20+ s-TILs, and high CD20+ intratumoral TILs, was independently associated with a higher pCR rate (P = 0.03). Analysis of single immune subpopulations revealed a significant association of pCR with higher baseline infiltration by s-CD4, intratumoral (i-) CD4, and i-CD20+ TILs. CONCLUSIONS: LPBC was marginally associated with higher pCR rate than non-LPBC in patients with lapatinib plus trastuzumab treated HER2+ breast cancer. Quantitative assessment of the immune infiltrate by m-IF is feasible and may help correlate individual immune cell subpopulations and immune cell profiles with treatment response.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/imunologia , Linfócitos do Interstício Tumoral/imunologia , Linfócitos/imunologia , Terapia Neoadjuvante/métodos , Receptor ErbB-2/imunologia , Receptor ErbB-2/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Seguimentos , Humanos , Lapatinib/administração & dosagem , Linfócitos/efeitos dos fármacos , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Pessoa de Meia-Idade , Prognóstico , Trastuzumab/administração & dosagem
5.
Am Fam Physician ; 100(9): 556-560, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674746

RESUMO

Childhood-onset fluency disorder, the most common form of stuttering, is a neurologic disability resulting from an underlying brain abnormality that causes disfluent speech. Stuttering can lead to significant secondary effects, including negative self-perception and negative perception by others, anxiety, and occasionally depression. Childhood-onset fluency disorder affects 5% to 10% of preschoolers. Early identification of stuttering is important so that therapy can begin while compensatory changes to the brain can still occur and to minimize the chances of the patient developing social anxiety, impaired social skills, maladaptive compensatory behaviors, and negative attitudes toward communication. However, stuttering may be persistent, even with early intervention, and affects about 1% of adults. In patients with persistent stuttering, speech therapy focuses on developing effective compensatory techniques and eliminating ineffective secondary behaviors. The role of family physicians includes facilitating early identification of children who stutter, arranging appropriate speech therapy, and providing support and therapy for patients experiencing psychosocial effects from stuttering. Finally, physicians can serve as advocates by making the clinic setting more comfortable for people who stutter and by educating teachers, coaches, employers, and others in the patient's life about the etiology of stuttering and the specific challenges patients face.


Assuntos
Guias de Prática Clínica como Assunto , Fonoterapia/normas , Gagueira/diagnóstico , Gagueira/terapia , Criança , Pré-Escolar , Currículo , Educação Médica Continuada , Feminino , Humanos , Masculino
6.
CMAJ ; 191(30): E844, 2019 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-31358602
7.
AIDS Care ; 31(7): 885-892, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30466303

RESUMO

We examined correlates of late and delayed initiation of antiretroviral therapy (ART) in British Columbia, Canada. From December 2013 to December 2015 we recruited treatment-naïve people living with HIV who initiated ART within the previous year. 'Late initiation' was defined as CD4 cell count ≤500 cells/µL at ART initiation and 'delayed initiation' as ≥1 year between HIV diagnosis and initiation. Multivariable logistic regression assessed independent correlates of late and delayed initiation. Of 87 participants, 44 (51%) initiated late and 22 (26%) delayed initiation. Delayed initiation was positively associated with older age (adjusted odds ratio [AOR]: 1.06 per year, 95% confidence interval [95% CI]: 1.01-1.12) and inversely associated with wanting to start ART at diagnosis (AOR: 0.06, 95% CI: 0.02-0.21). Variables associated with late initiation were older age (AOR: 1.09 per year, 95% CI: 1.03-1.15) and medical reason(s) for initiation (AOR: 5.00, 95% CI: 1.41-17.86). Late initiation was less likely among those with greater perceived ART efficacy (AOR 0.94, 95% CI: 0.90-0.98) and history of incarceration (AOR: 0.12, 95% CI: 0.03-0.56). Disparities in timing of initiation were observed for age, perceived ART efficacy, and history of incarceration. Enhanced health services that address these factors may facilitate earlier treatment initiation.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Contagem de Linfócito CD4/estatística & dados numéricos , Diagnóstico Tardio/estatística & dados numéricos , Infecções por HIV/tratamento farmacológico , Tempo para o Tratamento , Adulto , Terapia Antirretroviral de Alta Atividade , Colúmbia Britânica , Estudos de Coortes , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/imunologia , Humanos , Masculino , Estado Civil , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo
8.
J Clin Oncol ; 26(25): 4078-85, 2008 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-18757322

RESUMO

PURPOSE: Substantial evidence implicates insulin-like growth factor-I (IGF-I) signaling in the development and progression of breast cancer. To more clearly elucidate the role of IGF in human breast cancer, we identified and then examined gene expression patterns of IGF-I-treated breast cancer cells. METHODS: MCF-7 cells were stimulated with IGF-I for 3 or 24 hours and were profiled for greater than 22,000 RNA transcripts. We defined an IGF-I signature pattern of more than 800 genes that were up- or downregulated at both time points. The gene signature was examined in clinical breast tumors and in experimental models that represented other oncogenic pathways. The signature was correlated with clinical and pathologic variables and with patient outcome. RESULTS: IGF-I caused temporal changes in gene expression that were strongly associated with cell proliferation, metabolism, and DNA repair. Genes with early and sustained regulation by IGF-I were highly enriched for transcriptional targets of the estrogen receptor (ER), Ras/extracellular signal-related kinase 1/2, and phosphatidylinositol 3-kinase/Akt/mammalian target of rapamycin pathways. In three large, independent data sets of profiled human breast tumors, the IGF-I signature was manifested in the majority of ER-negative breast tumors and in a subset (approximately 25%) of ER-positive breast tumors. Patients who had tumors that manifested the IGF-I signature (including patients who did not receive adjuvant therapy) had a shorter time to a poor outcome event. The IGF gene signature was highly correlated with numerous poor prognostic factors and was one of the strongest indicators of disease outcome. CONCLUSION: Transcriptional targets of IGF-I represent pathways of increased aggressiveness and possibly hormone independence in clinical breast cancers.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Perfilação da Expressão Gênica , Fator de Crescimento Insulin-Like I/metabolismo , Transcrição Gênica , Neoplasias da Mama/diagnóstico , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , Modelos de Riscos Proporcionais , RNA Mensageiro/metabolismo , Fatores de Tempo , Resultado do Tratamento
9.
Nonlinear Dynamics Psychol Life Sci ; 7(1): 87-98, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12876448

RESUMO

This paper proposes that the theory of local rules provides a model for explaining organizational behavior as an emergent property of a fitness landscape. While local rule theory has its genesis in evolutionary biology, this paper links it to work in computational mathematical organizational theory. It further proposes that there are conditions, characterized by coadaptation, under which rules will survive in relatively stable forms, and other conditions, characterized by competition, under which local rules will change. The paper then discusses how catastrophe analysis can provide insights into changing patterns of organizational interactions. A discussion of methodology outline shows developments in agent-based simulation modeling can contribute to the development of local rule theory.


Assuntos
Relações Interpessoais , Política Organizacional , Humanos , Comportamento Social
10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 67(2 Pt 2): 026211, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12636780

RESUMO

Vibrations of membranes with fractal boundaries (fractal drums) are investigated. Numerical results are presented for Koch drums of fractal dimension D(f)=3/2 at prefractal generations 1-3, and for Koch snowflake drums (D(f)=ln 4/ln 3) at generations 3 and 4. The results show that the low-frequency integrated densities of states (IDOS's) of the drums are well approximated by a two-term asymptotic of the form given by the modified Weyl-Berry (MWB) conjecture, which predicts a correction of DeltaN(Omega) proportional, variant Omega(D(f)) to the leading-order Weyl term. In the high-frequency regime, where the half wavelength is smaller than the smallest features of the prefractal perimeter, the two-term Weyl asymptotic is applicable, with DeltaN(Omega) approximately Omega. The results also indicate that oscillations in DeltaN(Omega) arise due to localization of the wave amplitude near the prefractal perimeter. It is argued that for a self-similar fractal boundary, the amplitude of the oscillations is asymptotically proportional to Omega(D(f)), which implies an O(Omega(D(f))), rather than the conjectured o(Omega(D(f))), error term for the asymptotic IDOS given by the MWB conjecture.

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