Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 16 de 16
Filter
1.
Nanoscale ; 13(21): 9808-9815, 2021 Jun 03.
Article in English | MEDLINE | ID: mdl-34031687

ABSTRACT

The photophysics of an inorganic/organic hybrid system was studied by time-resolved optical spectroscopy, focusing on the goal of increasing the two-photon efficiency of photoresponsive systems. The hybrid system consists of CdS/ZnS core/shell quantum dots (QDs) as energy donor and coumarin derivatives as energy acceptor molecules. The spectral overlap of QD emission and coumarin 343 absorption promotes a Förster resonance energy tranfer (FRET) mechanism leading to a FRET efficiency up to nearly 90%. Additionally, time-correlated single photon counting showed a faster fluorescence decay while acceptor molecules were attached to the QD surface. Femtosecond transient absorption measurements demonstrated an ultrafast FRET reaction. Importantly, FRET was observed also after two-photon excitation of the QDs indicating that the chosen QDs can act as two-photon antennas.

3.
J Dent Res ; 98(13): 1488-1496, 2019 12.
Article in English | MEDLINE | ID: mdl-31623509

ABSTRACT

Microbial communities along mucosal surfaces throughout the digestive tract are hypothesized as risk factors for impaired glucose regulation and the development of clinical cardiometabolic disease. We investigated whether baseline measures of subgingival microbiota predicted fasting plasma glucose (FPG) longitudinally. The Oral Infections, Glucose Intolerance and Insulin Resistance Study (ORIGINS) enrolled 230 diabetes-free adults (77% female) aged 20 to 55 y (mean ± SD, 34 ± 10 y) from whom baseline subgingival plaque and longitudinal FPG were measured. DNA was extracted from subgingival plaque, and V3 to V4 regions of the 16S rRNA gene were sequenced. FPG was measured at baseline and again at 2 y; glucose change was defined as follow-up minus baseline. Multivariable linear models regressed 2-y glucose change onto baseline measures of community diversity and abundances of 369 individual taxa. A microbial dysbiosis index (MDI) summarizing top individual taxa associated with glucose change was calculated and used in regression models. Models were adjusted for age, sex, race/ethnicity, education, smoking status, body mass index, and baseline glucose levels. Statistical significance was based on the false discovery rate (FDR; <0.05) or a Bonferroni-corrected P value of 1 × 10-4, derived from the initial 369 hypothesis tests for specific taxa. Mean 2-y FPG change was 1.5 ± 8 mg/dL. Baseline levels of 9 taxa predicted FPG change (all FDR <0.05), among which Stomatobaculum sp oral taxon 097 and Atopobium spp predicted greater FPG change, while Leptotrichia sp oral taxon 498 predicted lesser FPG change (all 3 P values, Bonferroni significant). The MDI explained 6% of variation in longitudinal glucose change (P < 0.001), and baseline glucose levels explained 10% of variation (P < 0.0001). FPG change values ± SE in the third versus first tertile of the MDI were 4.5 ± 0.9 versus 1.6 ± 0.9 (P < 1 × 10-4). Subgingival microbiota predict 2-y glucose change among diabetes-free men and women.


Subject(s)
Gingiva/microbiology , Glucose Intolerance , Insulin Resistance , Microbiota , Adult , Blood Glucose , Diabetes Mellitus , Female , Glucose , Humans , Infections , Male , Middle Aged , RNA, Ribosomal, 16S , Young Adult
4.
J Nat Prod ; 79(12): 3031-3038, 2016 Dec 23.
Article in English | MEDLINE | ID: mdl-28006908

ABSTRACT

Eleven new polyketides, pallidopenillines 1-11, were isolated from the alga-derived fungus Penicillium thomii. The structures of these compounds were established based on spectroscopic methods. The absolute configuration of pallidopenilline A (1) as 4R, 5S, 8S, 9R, 10R, 13R was established using a combination of the modified Mosher's method, X-ray analysis, and NOESY data. The absolute configurations of 2-5 were determined by time-dependent density functional theory calculations of the ECD spectra and ECD and NOESY data. It was shown that 1-acetylpallidopenilline A (2) and pallidopenilline G (10) inhibit the growth of colonies of 22Rv1 cells by 40% at 2 and 1 µM, respectively.


Subject(s)
Antineoplastic Agents/isolation & purification , Penicillium/chemistry , Polyketides/isolation & purification , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Drug Screening Assays, Antitumor , HCT116 Cells , Humans , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Polyketides/chemistry , Polyketides/pharmacology , Sargassum/microbiology
5.
Eur J Surg Oncol ; 38(3): 222-9, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22231127

ABSTRACT

AIMS: We compared histological patterns after lumpectomy for non-palpable breast cancers preoperatively localized by radioguided occult lesion localization plus sentinel node localization (SNOLL) versus wire-guided localization. METHODS: To ensure a homogeneously treated cohort and rigorous comparisons, only patients with invasive cancer and measurable opacity by imaging were included. Exclusion criteria were one or more parameters that could interfere with localization and/or the surgical procedure. Forty-three SNOLL were compared with 86 WGL plus sentinel node (SN) localization. Cancer localization effectiveness was based on careful assessment of histological data from only the first resected glandular specimen, as any additional resection specimens were guided by intraoperative histological examination. RESULTS: Reexcisions to ensure free tissue margins were performed during the same procedure in 13.9% of SNOLL versus 31.3% of WGL; p = 0.02. Significantly more women in SNOLL (53.4%) also had free nearest margins of >9 mm after the first procedure compared with WGL (33.7%); p = 0.03. The median centricity ratio after the first procedure was better in SNOLL (2.8, range 1.3-14) than WGL (5, range 1-50); p = 0.008. The median number of SN detected by lymphoscintigraphy was the same in SNOLL and WGL (1, range 0-9, vs. 1, range 0-8). Intraoperative SN detection by blue dye and/or gamma probe was successful for 97.6% of SNOLL versus 93% of WGL. CONCLUSION: In this study, SNOLL was effective and safe, and this procedure significantly improved the rate of negative margins in the first specimen and the rate of reexcision for positive margins compared with WGL.


Subject(s)
Breast Neoplasms/diagnostic imaging , Breast Neoplasms/pathology , Breast Neoplasms/surgery , Multimodal Imaging , Positron-Emission Tomography , Sentinel Lymph Node Biopsy , Tomography, X-Ray Computed , Case-Control Studies , Chi-Square Distribution , Coloring Agents , Female , Humans , Lymphatic Metastasis/diagnostic imaging , Lymphatic Metastasis/pathology , Lymphoscintigraphy , Mastectomy, Segmental , Middle Aged , Neoplasm Invasiveness , Radiopharmaceuticals , Reoperation , Retrospective Studies , Statistics, Nonparametric , Technetium Tc 99m Sulfur Colloid
8.
J Cosmet Sci ; 56(1): 65-77, 2005.
Article in English | MEDLINE | ID: mdl-15744444

ABSTRACT

The application of surface specific x-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) will be shown to be an effective means for the elucidation of hair fiber surface chemistry and structure. Example studies of bleaching and fiber conditioning treatments are discussed. The bleached fiber surface is found to become more hydrophilic due to the loss of the naturally occurring hydrocarbon overlayer and oxidation of surface functional groups as a result of bleaching. Comparison between generic bleaching regimens illustrates the importance of increased pH and the presence of surfactant for effective treatment. Adsorption of conditioning diester quat and dimethicone molecules reintroduces a hydrophobic like surface layer on the hair fiber. Spectroscopic data indicated a segregated adsorption structure of the chemically different conditioning molecules. Electron microscope images of the conditioned hair shows a smooth uniform surface.


Subject(s)
Hair/chemistry , Hair/ultrastructure , Spectrum Analysis/methods , Hydrogen Peroxide/chemistry , Hydrogen-Ion Concentration , Microscopy, Electron, Scanning , Surface-Active Agents/chemistry
9.
Opt Lett ; 21(10): 740-2, 1996 May 15.
Article in English | MEDLINE | ID: mdl-19876143

ABSTRACT

A novel wavelength-selective photonic time-delay filter is proposed and demonstrated. The device consists of an optical phased-array waveguide grating in a recirculating feedback configuration. It can function as a true-time-delay generator for squint-free beam steering in optically controlled phased-array antennas and as an encoding-decoding filter for wavelength code-division multiple access.

10.
J Rheumatol ; 13(3): 637-40, 1986 Jun.
Article in English | MEDLINE | ID: mdl-3735285

ABSTRACT

A 31-year-old woman with systemic lupus erythematosus (SLE) taking chronic corticosteroid therapy developed Kaposi's sarcoma. Three weeks after a single intravenous dose of cyclophosphamide for central nervous system vasculitis she died. Autopsy revealed disseminated Kaposi's sarcoma involving the skin and lung, as well as other visceral organs. This is the first case of widespread Kaposi's sarcoma developing in a patient with SLE.


Subject(s)
Lung Neoplasms/complications , Lupus Erythematosus, Systemic/complications , Sarcoma, Kaposi/complications , Skin Neoplasms/complications , Adrenal Cortex Hormones/therapeutic use , Adult , Cyclophosphamide/therapeutic use , Female , Humans , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/drug therapy , Lung Neoplasms/pathology , Lupus Erythematosus, Systemic/drug therapy , Lupus Erythematosus, Systemic/pathology , Radiography , Sarcoma, Kaposi/diagnostic imaging , Sarcoma, Kaposi/drug therapy , Sarcoma, Kaposi/pathology , Skin Neoplasms/diagnostic imaging , Skin Neoplasms/drug therapy , Skin Neoplasms/pathology
SELECTION OF CITATIONS
SEARCH DETAIL
...