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1.
Proc Natl Acad Sci U S A ; 121(20): e2322688121, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38709925

RESUMO

Brain metastatic breast cancer is particularly lethal largely due to therapeutic resistance. Almost half of the patients with metastatic HER2-positive breast cancer develop brain metastases, representing a major clinical challenge. We previously described that cancer-associated fibroblasts are an important source of resistance in primary tumors. Here, we report that breast cancer brain metastasis stromal cell interactions in 3D cocultures induce therapeutic resistance to HER2-targeting agents, particularly to the small molecule inhibitor of HER2/EGFR neratinib. We investigated the underlying mechanisms using a synthetic Notch reporter system enabling the sorting of cancer cells that directly interact with stromal cells. We identified mucins and bulky glycoprotein synthesis as top-up-regulated genes and pathways by comparing the gene expression and chromatin profiles of stroma-contact and no-contact cancer cells before and after neratinib treatment. Glycoprotein gene signatures were also enriched in human brain metastases compared to primary tumors. We confirmed increased glycocalyx surrounding cocultures by immunofluorescence and showed that mucinase treatment increased sensitivity to neratinib by enabling a more efficient inhibition of EGFR/HER2 signaling in cancer cells. Overexpression of truncated MUC1 lacking the intracellular domain as a model of increased glycocalyx-induced resistance to neratinib both in cell culture and in experimental brain metastases in immunodeficient mice. Our results highlight the importance of glycoproteins as a resistance mechanism to HER2-targeting therapies in breast cancer brain metastases.


Assuntos
Neoplasias Encefálicas , Neoplasias da Mama , Resistencia a Medicamentos Antineoplásicos , Glicocálix , Quinolinas , Receptor ErbB-2 , Células Estromais , Humanos , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Feminino , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/genética , Receptor ErbB-2/metabolismo , Receptor ErbB-2/genética , Glicocálix/metabolismo , Animais , Linhagem Celular Tumoral , Células Estromais/metabolismo , Células Estromais/patologia , Quinolinas/farmacologia , Camundongos , Comunicação Celular , Técnicas de Cocultura , Mucina-1/metabolismo , Mucina-1/genética , Transdução de Sinais , Receptores ErbB/metabolismo , Receptores ErbB/antagonistas & inibidores
2.
Proc Natl Acad Sci U S A ; 120(20): e2220852120, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37155895

RESUMO

Many photonic and electronic molecular properties, as well as chemical and biochemical reactivities are controlled by fast intramolecular vibrational energy redistribution (IVR). This fundamental ultrafast process limits coherence time in applications from photochemistry to single quantum level control. While time-resolved multidimensional IR-spectroscopy can resolve the underlying vibrational interaction dynamics, as a nonlinear optical technique it has been challenging to extend its sensitivity to probe small molecular ensembles, achieve nanoscale spatial resolution, and control intramolecular dynamics. Here, we demonstrate a concept how mode-selective coupling of vibrational resonances to IR nanoantennas can reveal intramolecular vibrational energy transfer. In time-resolved infrared vibrational nanospectroscopy, we measure the Purcell-enhanced decrease of vibrational lifetimes of molecular vibrations while tuning the IR nanoantenna across coupled vibrations. At the example of a Re-carbonyl complex monolayer, we derive an IVR rate of (25±8) cm-1 corresponding to (450±150) fs, as is typical for the fast initial equilibration between symmetric and antisymmetric carbonyl vibrations. We model the enhancement of the cross-vibrational relaxation based on intrinsic intramolecular coupling and extrinsic antenna-enhanced vibrational energy relaxation. The model further suggests an anti-Purcell effect based on antenna and laser-field-driven vibrational mode interference which can counteract IVR-induced relaxation. Nanooptical spectroscopy of antenna-coupled vibrational dynamics thus provides for an approach to probe intramolecular vibrational dynamics with a perspective for vibrational coherent control of small molecular ensembles.

3.
Proc Natl Acad Sci U S A ; 120(49): e2316763120, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38011567

RESUMO

Immune escape is a prerequisite for tumor growth. We previously described a decline in intratumor activated cytotoxic T cells and T cell receptor (TCR) clonotype diversity in invasive breast carcinomas compared to ductal carcinoma in situ (DCIS), implying a central role of decreasing T cell responses in tumor progression. To determine potential associations between peripheral immunity and breast tumor progression, here, we assessed the peripheral blood TCR clonotype of 485 breast cancer patients diagnosed with either DCIS or de novo stage IV disease at younger (<45) or older (≥45) age. TCR clonotype diversity was significantly lower in older compared to younger breast cancer patients regardless of tumor stage at diagnosis. In the younger age group, TCR-α clonotype diversity was lower in patients diagnosed with de novo stage IV breast cancer compared to those diagnosed with DCIS. In the older age group, DCIS patients with higher TCR-α clonotype diversity were more likely to have a recurrence compared to those with lower diversity. Whole blood transcriptome profiles were distinct depending on the TCR-α Chao1 diversity score. There were more CD8+ T cells and a more active immune environment in DCIS tumors of young patients with higher peripheral blood TCR-α Chao1 diversity than in those with lower diversity. These results provide insights into the role that host immunity plays in breast cancer development across different age groups.


Assuntos
Neoplasias da Mama , Carcinoma Ductal de Mama , Carcinoma Intraductal não Infiltrante , Humanos , Idoso , Feminino , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/genética , Carcinoma Intraductal não Infiltrante/patologia , Linfócitos T CD8-Positivos/patologia , Biomarcadores Tumorais/genética , Receptores de Antígenos de Linfócitos T/genética , Processos Neoplásicos , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Carcinoma Ductal de Mama/patologia
4.
Nano Lett ; 24(3): 836-843, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38193723

RESUMO

Tip-enhanced vibrational spectroscopy has advanced to routinely attain nanoscale spatial resolution, with tip-enhanced Raman spectroscopy even achieving atomic-scale and submolecular sensitivity. Tip-enhanced infrared spectroscopy techniques, such as nano-FTIR and AFM-IR spectroscopy, have also enabled the nanoscale chemical analysis of molecular monolayers, inorganic nanoparticles, and protein complexes. However, fundamental limits of infrared nanospectroscopy in terms of spatial resolution and sensitivity have remained elusive, calling for a quantitative understanding of the near-field interactions in infrared nanocavities. Here, we demonstrate the application of nano-FTIR spectroscopy to probe the amide-I vibration of a single protein consisting of ∼500 amino acid residues. Detection with higher tip tapping demodulation harmonics up to the seventh order leads to pronounced enhancement in the peak amplitude of the vibrational resonance, originating from sub-tip-radius geometrical effects beyond dipole approximations. This quantitative characterization of single-nanometer near-field interactions opens the path toward employing infrared vibrational spectroscopy at the subnanoscale and single-molecule levels.


Assuntos
Rádio (Anatomia) , Vibração , Microscopia de Força Atômica , Nanotecnologia/métodos , Espectroscopia de Infravermelho com Transformada de Fourier
5.
J Orthop Sci ; 28(3): 507-508, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37088641

RESUMO

BACKGROUND: Several procedures of biological reconstruction for massive bone defect are available following tumor resection. Since the 1980s, allografting has been advanced mainly in the United States. However, allogeneic bone grafting has not been sufficiently developed in Japan for socioreligious reasons, and many other biological reconstructive methods have been developed. STATUS OF BIOLOGICAL RECONSTRUCTION: Bone lengthening, recycled and vascularized bone grafting have yielded favorable outcomes. Once bone union is achieved, reoperation is scarcely performed, with lower rate of infection than that observed with a prosthesis. However, there are disadvantages, such as complicated surgical procedures and relatively common postoperative complications. However, if sufficient donors are available, allogeneic bone grafting can be a good alternative. PROSPECTS OF THE JAPANESE ORTHOPAEDIC ASSOCIATION: Regenerative medicine with iPS cells, etc., which is under investigation, is expected to be employed for defect reconstruction. However, several biological reconstructive procedures should be further developed. These procedures are not inferior to prosthetic and allograft reconstructions in the short term, but rather are superior in the long term. Favorable outcomes are being obtained by combining recycled bone reconstruction and vascularized bone grafting, suggesting possible improvement in the future. Data should be accumulated to develop biological reconstruction in Japan. Although Japan has the challenge in terms of the ability to convey its message, the disadvantages of the procedures should be minimized. CONCLUSION: The construction of an allogeneic bone grafting system should be promoted, while biological reconstruction methods developed in Japan should be further developed and convey our message clearly and logically.


Assuntos
Neoplasias Ósseas , Procedimentos de Cirurgia Plástica , Humanos , Neoplasias Ósseas/cirurgia , Neoplasias Ósseas/patologia , Japão , Resultado do Tratamento , Complicações Pós-Operatórias/cirurgia , Transplante Ósseo/métodos , Estudos Retrospectivos
6.
J Chem Phys ; 156(12): 124110, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35364879

RESUMO

Nanoscale infrared (IR) resonators with sub-diffraction limited mode volumes and open geometries have emerged as new platforms for implementing cavity quantum electrodynamics at room temperature. The use of IR nanoantennas and tip nanoprobes to study strong light-matter coupling of molecular vibrations with the vacuum field can be exploited for IR quantum control with nanometer spatial and femtosecond temporal resolution. In order to advance the development of molecule-based quantum nanophotonics in the mid-IR, we propose a generally applicable semi-empirical methodology based on quantum optics to describe light-matter interaction in systems driven by mid-IR femtosecond laser pulses. The theory is shown to reproduce recent experiments on the acceleration of the vibrational relaxation rate in infrared nanostructures. It also provides physical insights on the implementation of coherent phase rotations of the near-field using broadband nanotips. We then apply the quantum framework to develop general tip-design rules for the experimental manipulation of vibrational strong coupling and Fano interference effects in open infrared resonators. We finally propose the possibility of transferring the natural anharmonicity of molecular vibrational levels to the resonator near-field in the weak coupling regime to implement intensity-dependent phase shifts of the coupled system response with strong pulses and develop a vibrational chirping model to understand the effect. The semi-empirical quantum theory is equivalent to first-principles techniques based on Maxwell's equations, but its lower computational cost suggests its use as a rapid design tool for the development of strongly coupled infrared nanophotonic hardware for applications ranging from quantum control of materials to quantum information processing.

7.
J Orthop Sci ; 27(4): 798-803, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34090777

RESUMO

BACKGROUND: The present study aimed to identify risk factors for preoperative nasal carriage of resistant bacteria - MRSA methicillin-resistant Staphylococcus (S.) aureus, MRSE (methicillin-resistant Staphylococcus epidermidis), and MRCNS (methicillin-resistant coagulase negative staphylococci) in total hip and knee arthroplasty (THA and TKA) patients. METHODS: Nasal cultures were obtained from 538 patients before THA (262 primary and 26 revision) and TKA (241 primary and 9 revision). These were classified either as methicillin-resistant bacteria (group MR) or methicillin-susceptible bacteria (including culture-negative) (group MS). Patient characteristics were compared between these groups using logistic regression models. RESULTS: The resistant bacteria were preoperatively present in 33.1% (178 patients) among all patients. MRSE, MRCNS, and MRSA were detected in 27.5% (148 patients), 3.7% (20 patients), and 1.9% (10 patients). In the unadjusted comparisons of the patient characteristics between the groups MR and MS, a significant difference was found in the percentages of diabetic patients (15.2% vs. 9.2%, P = 0.04); the association remained after the multivariable adjustment for possible risk factors (P < 0.001). In addition, the diabetic patients in the group MR showed a higher percentage of receiving insulin injection than those in the group MS (25.9% vs. 6.1%, P = 0.063), and their mean levels of HbA1c were significantly higher in the group MR than the MS (6.8% vs. 6.4%, P = 0.03). CONCLUSIONS: We identified diabetes as a risk factor for the preoperative nasal carriage of resistant bacteria. Our results suggest that, in order to prevent a surgical site infection (SSI), extra care should be taken in performing joint arthroplasties for diabetic patients, especially using insulin and with high HbA1c levels (≥6.6%) prior to the surgical procedures.


Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Insulinas , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Antibacterianos/uso terapêutico , Artroplastia do Joelho/efeitos adversos , Hemoglobinas Glicadas , Humanos , Meticilina , Resistência a Meticilina , Fatores de Risco , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus
8.
Nano Lett ; 21(13): 5754-5759, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34156252

RESUMO

Order, disorder, and domains affect many of the functional properties in self-assembled monolayers (SAMs). However, carrier transport, wettability, and chemical reactivity are often associated with collective effects, where conventional imaging techniques have limited sensitivity to the underlying intermolecular coupling. Here we demonstrate vibrational excitons as a molecular ruler of intermolecular wave function delocalization and nanodomain size in SAMs. In the model system of a 4-nitrothiophenol (4-NTP) SAM on gold, we resolve coupling-induced peak shifts of the nitro symmetric stretch mode with full spatio-spectral infrared scattering scanning near-field optical microscopy. From modeling of the underlying 2D Hamiltonian, we infer domain sizes and their distribution ranging from 3 to 12 nm across a field of view on the micrometer scale. This approach of vibrational exciton nanoimaging is generally applicable to study structural phases and domains in SAMs and other molecular interfaces.

9.
Nano Lett ; 21(15): 6463-6470, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34310158

RESUMO

A hierarchy of intramolecular and intermolecular interactions controls the properties of biomedical, photophysical, and novel energy materials. However, multiscale heterogeneities often obfuscate the relationship between microscopic structure and emergent function, and they are generally difficult to access with conventional optical and electron microscopy techniques. Here, we combine vibrational exciton nanoimaging in variable-temperature near-field optical microscopy (IR s-SNOM) with four-dimensional scanning transmission electron microscopy (4D-STEM), and vibrational exciton modeling based on density functional theory (DFT), to link local microscopic molecular interactions to macroscopic three-dimensional order. In the application to poly(tetrafluoroethylene) (PTFE), large spatio-spectral heterogeneities with C-F vibrational energy shifts ranging from sub-cm-1 to ≳25 cm-1 serve as a molecular ruler of the degree of local crystallinity and disorder. Spatio-spectral-structural correlations reveal a previously invisible degree of highly variable local disorder in molecular coupling as the possible missing link between nanoscale morphology and associated electronic, photonic, and other functional properties of molecular materials.


Assuntos
Microscopia , Vibração
10.
Int J Mol Sci ; 23(12)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35743163

RESUMO

Mucin 21(Muc21)/epiglycanin is expressed on apical surfaces of squamous epithelia and has potentially protective roles, which are thought to be associated with its unique glycoforms, whereas its aberrant glycosylation is implicated in the malignant behaviors of some carcinomas. Despite the importance of glycoforms, we lack tools to detect specific glycoforms of mouse Muc21. In this study, we generated two monoclonal antibodies (mAbs) that recognize different glycoforms of Muc21. We used membrane lysates of Muc21-expressing TA3-Ha cells or Chinese hamster ovary (CHO)-K1 cells transfected with Muc21 as antigens. Specificity testing, utilizing Muc21 glycosylation variant cells, showed that mAb 1A4-1 recognized Muc21 carrying glycans terminated with galactose residues, whereas mAb 18A11 recognized Muc21 carrying sialylated glycans. mAb 1A4-1 stained a majority of mouse mammary carcinoma TA3-Ha cells in vitro and in engrafted tumors in mice, whereas mAb 18A11 recognized only a subpopulation of these. mAb 1A4-1 was useful in immunohistochemically detecting Muc21 in normal squamous epithelia. In conclusion, these mAbs recognize distinct Muc21 epitopes formed by combinations of peptide portions and O-glycans.


Assuntos
Antineoplásicos Imunológicos , Carcinoma de Células Escamosas , Animais , Anticorpos Monoclonais , Células CHO , Cricetinae , Cricetulus , Camundongos , Mucina-1/química , Mucinas/química , Polissacarídeos/química
11.
Cancer Sci ; 112(8): 3136-3149, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34091990

RESUMO

Intratumoral heterogeneity, including in clear cell renal cell carcinoma, is a potential cause of drug resistance and metastatic cancer progression. We specified the heterogeneous population marked by endoglin (also known as CD105) in a preclinical model of clear cell renal cell carcinoma progression. Highly malignant derivatives of human clear cell renal cell carcinoma OS-RC-2 cells were established as OS5Ks by serial orthotopic inoculation in our previous study. Expression of both ENG (encoding endoglin) mRNA and protein were heterogeneously upregulated in OS5Ks, and the endoglin-positive (ENG+ ) population exhibited growth dependency on endoglin in anchorage-independent cultures. Despite the function of endoglin as a type III receptor, transforming growth factor ß and bone morphogenetic protein-9 signaling were unlikely to contribute to the proliferative phenotype. Although endoglin has been proposed as a marker for renal cancer-initiating cells, the OS5K-3 ENG+ population did not enrich other reported cancer-initiating cell markers or differentiate into the ENG- population. Mouse tumor inoculation models revealed that the tumor-forming capabilities of OS5K-3 ENG+ and ENG- cells in vivo were highly dependent on the microenvironment, with the renal microenvironment most preferable to ENG+ cells. In conclusion, the renal microenvironment, rather than the hypothesized ENG+ cell-centered hierarchy, maintains cellular heterogeneity in clear cell renal cell carcinoma. Therefore, the effect of the microenvironment should be considered when evaluating the proliferative capability of renal cancer cells in the experimental settings.


Assuntos
Carcinoma de Células Renais/patologia , Endoglina/genética , Endoglina/metabolismo , Neoplasias Renais/patologia , Regulação para Cima , Animais , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Heterogeneidade Genética , Humanos , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Masculino , Camundongos , Transplante de Neoplasias , Células-Tronco Neoplásicas/metabolismo , Microambiente Tumoral
12.
Cancer Sci ; 110(11): 3486-3496, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31483918

RESUMO

Bone morphogenetic protein (BMP) signaling plays important roles in glioblastoma multiforme (GBM), a lethal form of brain tumor. BMP reduces GBM tumorigenicity through its differentiation- and apoptosis-inducing effects on glioma-initiating cells (GIC). However, some GIC do not respond to the tumor suppressive effects of BMP. Using a phosphoreceptor tyrosine kinase array, we found that EPHA6 (erythropoietin-producing hepatocellular carcinoma receptor A6) phosphorylation was regulated by BMP-2 signaling in some GIC. Analysis of The Cancer Genome Atlas showed that EPHA6 expression was lower in patients with GBM than in the normal brain, and that high EPHA6 expression was correlated with better prognosis. EPHA6 receptor increased the susceptibility of both sensitive and resistant GIC to BMP-2-induced apoptosis. The cooperative effect on apoptosis induction depended on the kinase activity of BMP type I receptor but was independent of EPHA6 kinase function. Overexpression of the EPHA6 receptor in GIC resulted in the formation of a protein complex of EPHA6 receptor and the BMP type I receptor ALK-2, which was associated with BMP-induced apoptosis in GIC. Intracranial injection of GIC into nude mice showed that gain-of-function of EPHA6 together with BMP-2 pretreatment slowed GBM tumor progression in the mouse brain and promoted mouse survival. In summary, EPHA6 together with BMP-2 signaling led to apoptotic cell death in GIC, and thus is a putative tumor suppressor in GBM.


Assuntos
Receptores de Ativinas Tipo I/metabolismo , Apoptose , Proteína Morfogenética Óssea 2/metabolismo , Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Receptor EphA6/metabolismo , Animais , Proteína Morfogenética Óssea 2/farmacologia , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Progressão da Doença , Glioblastoma/mortalidade , Glioblastoma/patologia , Glioma/metabolismo , Glioma/patologia , Humanos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Fosforilação , Prognóstico , Proteínas Supressoras de Tumor/metabolismo
13.
Phys Rev Lett ; 123(15): 153001, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31702318

RESUMO

Infrared (IR) spectroscopy of molecular vibrations provides insight into molecular structure, coupling, and dynamics. However, picosecond scale intermolecular and intramolecular many-body interactions, nonradiative relaxation, absorption, and thermalization typically dominate over IR spontaneous emission. We demonstrate how coupling to a resonant IR antenna can enhance spontaneous emission of molecular vibrations. Using time-domain nanoprobe spectroscopy we observe an up to 50% decrease in vibrational dephasing time T_{2,vib}, based on the coupling-induced population decay with T_{κ}≃550 fs and an associated Purcell factor of >10^{6}. This rate enhancement of the spontaneous emission of antenna-coupled molecular vibrations opens new avenues for IR coherent control, quantum information processing, and quantum chemistry.

14.
Proc Natl Acad Sci U S A ; 113(18): 4929-34, 2016 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-27044113

RESUMO

Functionalized self-assembled monolayers (SAMs) are the focus of ongoing investigations because they can be chemically tuned to control their structure and dynamics for a wide variety of applications, including electrochemistry, catalysis, and as models of biological interfaces. Here we combine reflection 2D infrared vibrational echo spectroscopy (R-2D IR) and molecular dynamics simulations to determine the relationship between the structures of functionalized alkanethiol SAMs on gold surfaces and their underlying molecular motions on timescales of tens to hundreds of picoseconds. We find that at higher head group density, the monolayers have more disorder in the alkyl chain packing and faster dynamics. The dynamics of alkanethiol SAMs on gold are much slower than the dynamics of alkylsiloxane SAMs on silica. Using the simulations, we assess how the different molecular motions of the alkyl chain monolayers give rise to the dynamics observed in the experiments.

16.
J Am Chem Soc ; 140(31): 9882-9890, 2018 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-30024160

RESUMO

The dynamically flexible lattices in lead halide perovskites may play important roles in extending carrier recombination lifetime in 3D perovskite solar-cell absorbers and in exciton self-trapping in 2D perovskite white-light phosphors. Two-dimensional infrared (2D IR) spectroscopy was applied to study a recently reported Pb-I-SCN layered perovskite. The Pb-I-SCN perovskite was spin-coated on a SiO2 surface as a thin film, with a thickness of ∼100 nm, where the S12CN- anions were isotopically diluted with the ratio of S12CN:S13CN = 5:95 to avoid vibrational coupling and excitation transfer between adjacent SCN- anions. The 12CN stretch mode of the minor S12CN- component was the principal vibrational probe that reported on the structural evolution through 2D IR spectroscopy. Spectral diffusion was observed with a time constant of 4.1 ± 0.3 ps. Spectral diffusion arises from small structural changes that result in sampling of frequencies within the distribution of frequencies comprising the inhomogeneously broadened infrared absorption band. These transitions among discrete local structures are distinct from oscillatory phonon motions of the lattice. To accurately evaluate the structural dynamics through measurement of spectral diffusion, the vibrational coupling between adjacent SCN- anions had to be carefully treated. Although the inorganic layers of typical 2D perovskites are structurally isolated from each other, the 2D IR data demonstrated that the layers of the Pb-I-SCN perovskite are vibrationally coupled. When both S12CN- and S13CN- were pumped simultaneously, cross-peaks between S12CN and S13CN vibrations and an oscillating 2D band shape of the S12CN- vibration were observed. Both observables demonstrate vibrational coupling between the closest SCN- anions, which reside in different inorganic layers. The thin films and the isotopic dilution produced exceedingly small vibrational echo signal fields; measurements were made possible using the near-Brewster's angle reflection pump-probe geometry.

17.
J Shoulder Elbow Surg ; 27(3): 510-514, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29269139

RESUMO

BACKGROUND: Scapulectomy is an inevitable treatment for sarcomas of the scapula. This procedure is unavoidable because it reduces the local recurrence rate but can impair shoulder movements and affect the activities of daily living. This study investigated the factors influencing functional outcomes after scapulectomy. MATERIALS AND METHODS: The clinical results of 8 patients (5 males, 3 females) who were diagnosed with primary or metastatic sarcomas of the scapula were retrospectively reviewed. The mean age was 49 years (range, 11-86 years). We examined the correlation between the type of excision of the scapula (total, subtotal, or partial) and postoperative functional outcomes according to the Musculoskeletal Tumor Society (MSTS) score. In partial excision, the glenohumeral joint was preserved; in subtotal excision, the glenoid was completely resected and some bony components were preserved; and in total excision, the entire bony component of the scapula was resected. The average follow-up period was 55 months (range, 9-142 months). RESULTS: The partial, subtotal, and total excision groups had mean functional scores of 96.7%, 76.7%, and 62.2%, respectively. Although the mean functional scores were lower in patients who underwent total and subtotal excisions, 3 patients in whom the latissimus dorsi muscle was preserved had better function (mean MSTS score, 76.7%) than the 2 patients in whom it was not preserved (mean MSTS score, 55.0%). CONCLUSION: These results suggest that the latissimus dorsi muscle, along with the deltoid and pectoralis major muscles, is one of the stabilizers of the proximal humerus after scapulectomy.


Assuntos
Neoplasias Ósseas/cirurgia , Neoplasias Musculares/secundário , Procedimentos Ortopédicos/métodos , Sarcoma/cirurgia , Escápula/cirurgia , Músculos Superficiais do Dorso/cirurgia , Atividades Cotidianas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/patologia , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Musculares/diagnóstico , Neoplasias Musculares/cirurgia , Estudos Retrospectivos , Sarcoma/diagnóstico , Sarcoma/secundário , Escápula/patologia , Músculos Superficiais do Dorso/diagnóstico por imagem , Músculos Superficiais do Dorso/fisiopatologia , Adulto Jovem
18.
J Am Chem Soc ; 139(46): 16518-16527, 2017 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-29072913

RESUMO

Monolayers play important roles in naturally occurring phenomena and technological processes. Monolayers at the air/water interface have received considerable attention, yet it has proven difficult to measure monolayer and interfacial molecular dynamics. Here we employ a new technique, reflection enhanced two-dimensional infrared (2D IR) spectroscopy, on a carbonyl stretching mode of tricarbonylchloro-9-octadecylamino-4,5-diazafluorenerhenium(I) (TReF18) monolayers at two surface densities. Comparison to experiments on a water-soluble version of the metal carbonyl headgroup shows that water hydrogen bond rearrangement dynamics slow from 1.5 ps in bulk water to 3.1 ps for interfacial water. Longer time scale fluctuations were also observed and attributed to fluctuations of the number of hydrogen bonds formed between water and the three carbonyls of TReF18. At the higher surface density, two types of TReF18 minor structures are observed in addition to the main structure. The reflection method can take usable 2D IR spectra on the monolayer within 8 s, enabling us to track the fluctuating minor structures' appearance and disappearance on a tens of seconds time scale. 2D IR chemical exchange spectroscopy further shows these structures interconvert in 30 ps. Finally, 2D spectral line shape evolution reveals that it takes the monolayers hours to reach macroscopic structural equilibrium.

19.
Proc Natl Acad Sci U S A ; 111(52): 18442-7, 2014 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-25512539

RESUMO

The structural elasticity of metal-organic frameworks (MOFs) is a key property for their functionality. Here, we show that 2D IR spectroscopy with pulse-shaping techniques can probe the ultrafast structural fluctuations of MOFs. 2D IR data, obtained from a vibrational probe attached to the linkers of UiO-66 MOF in low concentration, revealed that the structural fluctuations have time constants of 7 and 670 ps with no solvent. Filling the MOF pores with dimethylformamide (DMF) slows the structural fluctuations by reducing the ability of the MOF to undergo deformations, and the dynamics of the DMF molecules are also greatly restricted. Methodology advances were required to remove the severe light scattering caused by the macroscopic-sized MOF particles, eliminate interfering oscillatory components from the 2D IR data, and address Förster vibrational excitation transfer.

20.
J Am Chem Soc ; 138(30): 9694-703, 2016 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-27385320

RESUMO

Water of hydration plays an important role in minerals, determining their crystal structures and physical properties. Here ultrafast nonlinear infrared (IR) techniques, two-dimensional infrared (2D IR) and polarization selective pump-probe (PSPP) spectroscopies, were used to measure the dynamics and disorder of water of hydration in two minerals, gypsum (CaSO4·2H2O) and bassanite (CaSO4·0.5H2O). 2D IR spectra revealed that water arrangement in freshly precipitated gypsum contained a small amount of inhomogeneity. Following annealing at 348 K, water molecules became highly ordered; the 2D IR spectrum became homogeneously broadened (motional narrowed). PSPP measurements observed only inertial orientational relaxation. In contrast, water in bassanite's tubular channels is dynamically disordered. 2D IR spectra showed a significant amount of inhomogeneous broadening caused by a range of water configurations. At 298 K, water dynamics cause spectral diffusion that sampled a portion of the inhomogeneous line width on the time scale of ∼30 ps, while the rest of inhomogeneity is static on the time scale of the measurements. At higher temperature, the dynamics become faster. Spectral diffusion accelerates, and a portion of the lower temperature spectral diffusion became motionally narrowed. At sufficiently high temperature, all of the dynamics that produced spectral diffusion at lower temperatures became motionally narrowed, and only homogeneous broadening and static inhomogeneity were observed. Water angular motions in bassanite exhibit temperature-dependent diffusive orientational relaxation in a restricted cone of angles. The experiments were made possible by eliminating the vast amount of scattered light produced by the granulated powder samples using phase cycling methods.

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