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1.
Breast ; 74: 103693, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38430905

ABSTRACT

BACKGROUND: High breast density is an independent risk factor for breast cancer and decreases the sensitivity of mammography. This systematic review synthesizes the evidence on the impact of breast density (BD) information and/or notification on women's psychosocial outcomes among women from racial and ethnic minority groups. METHODS: A systematic search was performed in March 2023, and the articles were identified using CINHAL, Embase, Medline, and PsychInfo databases. The search strategy combined the terms "breast", "density", "notification" and synonyms. The authors specifically kept the search terms broad and did not include terms related to race and ethnicity. Full-text articles were reviewed for analysis by race, ethnicity and primary language of participants. Two authors evaluated the eligibility of studies with verification from the study team, extracted and crosschecked data, and assessed the risk of bias. RESULTS: Of 1784 articles, 32 articles published from 2003 to 2023 were included. Thirty-one studies were conducted in the United States and one in Australia, with 28 quantitative and four qualitative methodologies. The overall results in terms of breast density awareness, knowledge, communication with healthcare professionals, screening intentions and supplemental screening practice were heterogenous across studies. Barriers to understanding BD notifications and intentions/access to supplemental screening among racial and ethnic minorities included socioeconomic factors, language, health literacy and medical mistrust. CONCLUSIONS: A one-size approach to inform women about their BD may further disadvantage racial and ethnic minority women. BD notification and accompanying information should be tailored and translated to ensure readability and understandability by all women.


Subject(s)
Breast Density , Breast Neoplasms , Female , Humans , United States , Breast Neoplasms/psychology , Ethnicity , Ethnic and Racial Minorities , Trust , Minority Groups
7.
J Mater Chem B ; 4(1): 162-168, 2016 Jan 07.
Article in English | MEDLINE | ID: mdl-32262820

ABSTRACT

Organic Field Effect Transistors (OFETs) are used to measure ammonia in solution via ammonia diffusion into the OFET channel. An increase in ammonia concentrations results in a decrease in transistor currents. The regeneration of the OFET current after ammonia uptake is slow, which allows us to read out the maximum ammonia dose which was applied. A 100 nm parylene-C layer serves as a semipermeable top gate dielectric. The parylene layer is functionalized with the covalently attached enzyme urease. The enzyme catalyses the hydrolysis of urea to ammonia and carbon dioxide, i.e. urea can be detected via its hydrolysis product ammonia. The sensitivity covers a range of physiological concentrations of urea, which are several mM.

8.
Langmuir ; 28(29): 10818-21, 2012 Jul 24.
Article in English | MEDLINE | ID: mdl-22789026

ABSTRACT

Lipid bilayers with a controlled content of anionic lipids are a prerequisite for the quantitative study of hydrophobic-electrostatic interactions of proteins with lipid bilayers. Here, the asymmetric distribution of zwitterionic and anionic lipids in supported lipid bilayers is studied by neutron reflectometry. We prepare POPC/POPS (3:1) unilamellar vesicles in a high-salt-concentration buffer. Initially, no fusion of the vesicles to a SiO(2) surface is observed over hours and days. Once the isotonic buffer is exchanged with hypotonic buffer, vesicle fusion and bilayer formation occur by osmotic shock. Neutron reflectivity on the bilayers formed this way reveals the presence of anionic lipids (d(31)-POPS) in the outer bilayer leaflet only, and no POPS is observed in the leaflet facing the SiO(2) substrate. We argue that this asymmetric distribution of POPS is induced by the electrostatic repulsion of the phosphatidylserines from the negatively charged hydroxy surface groups of the silicon block. Such bilayers with controlled and high contents of anionic lipids in the outer leaflet are versatile platforms for studying anionic lipid protein interactions that are key elements in signal transduction pathways in the cytoplasmic leaflet of eukaryotic cells.


Subject(s)
Lipid Bilayers/chemistry , Phospholipids/chemistry , Anions/chemistry , Silicon Dioxide/chemistry , Surface Properties
9.
Int Breastfeed J ; 7: 2, 2012 Feb 24.
Article in English | MEDLINE | ID: mdl-22364405

ABSTRACT

BACKGROUND: Malnutrition is a major public health problem in developing countries and exclusive breastfeeding is an efficient strategy that can be used to prevent malnutrition and reduce child mortality. The objective of this study is to evaluate the effectiveness of community volunteers in promoting exclusive breastfeeding from birth in an area of endemic malnutrition. METHODS: This evaluation analyzed the impact of the community-based nutrition project in Katana health district of the Democratic Republic of Congo from 2004 to 2006. Each of the villages in this sector had a nutritional village committee made up of five members responsible for continuously working to raise awareness of the importance of exclusive breastfeeding from birth among pregnant women and community leaders in their respective villages. The program worked with community volunteers with a mean age of 37 years, most of whom were married (86%). Eighty percent of the community volunteers had completed secondary school or a higher level of education. Data related to the period of exclusive breastfeeding and to the number of visits made to the health services for 208 children. The data were compared with data from 178 infants collected from another health sector, which had never developed a community-based nutrition program. RESULTS: The duration of exclusive breastfeeding from birth (median, range) was 6 months (2 to 7) in the intervention area compared with 4 months (1 to 6) in the comparison area (p < 0.001). The proportion of infants receiving exclusive breastfeeding at six months of age was higher in the intervention area than in the comparison area: 57.7% (95% Confidence Interval, CI, 50.9 to 64.5) versus 2.7% (95%CI, 1.1 to 6.6) (p < 0.001). The intervention group had a higher mean weight at 12 months (standard deviation): 8.42 kg (1.41) compared to 7.97 kg (1.02), although this difference was not statistically significant (p = 0.055). CONCLUSIONS: The promotion of breastfeeding by community volunteers in an area of endemic malnutrition in rural Democratic Republic of Congo increased the duration of exclusive breastfeeding from birth.

11.
Biotech Histochem ; 84(3): 109-15, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19353361

ABSTRACT

Our current understanding of clathrin-mediated endocytosis proposes that the process is initiated at a specialized anatomical structure called a coated pit. Electron microscopy has been required for elucidation of the morphology of coated pits and the vesicles produced therein, and the presence of a bristle coat has been taken as suggestive of clathrin surrounding these vesicles. More recently, immunocytochemical methods have confirmed that endocytic vesicles are surrounded by clathrin and its adaptor proteins, but there is a need to identify precisely and to follow the fate of the cellular organelles seen by fluorescence microscopy. We used quantum immune-electron microscopy to localize clathrin in a human adrenal cortical cell line (SW-13). Clathrin was shown to associate with a variety of vesicle types including the classic clathrin-coated vesicles and pits used in receptor internalization, pentilaminar annular gap junction vesicles, and multivesicular bodies. The images obtained with quantum dot technology allow accurate and specific localization of clathrin and the clathrin adaptor protein, AP-2, with cellular organelles and suggest that some of the structures classified as typical coated vesicles by immunocytochemical light microscopic techniques actually may be membrane bound pits.


Subject(s)
Clathrin-Coated Vesicles/metabolism , Clathrin-Coated Vesicles/ultrastructure , Clathrin/metabolism , Clathrin/ultrastructure , Image Enhancement/methods , Microscopy, Fluorescence/methods , Quantum Dots
12.
Mol Cell Endocrinol ; 300(1-2): 51-6, 2009 Mar 05.
Article in English | MEDLINE | ID: mdl-18973789

ABSTRACT

Gap junctions are membrane specializations that are composed of connexin protein. The assembly of these proteins into channels between cells allows for the intercellular transfer of regulatory molecules. In the adrenal gland, as in most other tissues, intercellular communication provides the potential for regulation of a number of complex interactive cell processes including differentiation, steroidogenesis, migration, and proliferation. This review is concerned with the regulation of gap junctions and cell function in cortical cells of the adrenal gland and in pathological disorders such as adrenal cancer.


Subject(s)
Adrenal Cortex , Cell Proliferation , Gap Junctions/metabolism , Steroids/biosynthesis , Adrenal Cortex/cytology , Adrenal Cortex/physiology , Adrenal Cortex Neoplasms/metabolism , Adrenal Cortex Neoplasms/physiopathology , Adrenal Medulla/cytology , Adrenal Medulla/physiology , Animals , Cell Movement/physiology , Connexins/metabolism , Gap Junctions/ultrastructure
13.
Phys Rev Lett ; 99(17): 176402, 2007 Oct 26.
Article in English | MEDLINE | ID: mdl-17995352

ABSTRACT

The exciton dynamics in microcrystalline pentacene films is investigated by transient absorption measurements with 30 fs time resolution. It is found that the emission from photoexcited Frenkel excitons decays within 70 fs due to the ultrafast formation of an excitonic species with a strongly reduced transition dipole to the ground state and an absorption dipole in the plane of the film. We propose that an excimer exciton is formed and stabilized by changes of the local crystal structure. The subsequent dynamics is dominated by diffusion controlled annihilation and trapping.

14.
Phys Rev Lett ; 96(15): 156803, 2006 Apr 21.
Article in English | MEDLINE | ID: mdl-16712184

ABSTRACT

Evidence for temperature-dependent electron band dispersion in a pentacene thin film polymorph on graphite is provided by angle- and energy-dependent ultraviolet photoelectron spectroscopy. The bands derived from the highest occupied molecular orbital exhibit dispersion of approximately 190 meV at room temperature, and approximately 240 meV at 120 K. Intermolecular electronic coupling in pentacene thin films is thus confirmed to be dependent on temperature and possibly crystal structure, as suggested by additional infrared absorption measurements.

15.
Phys Rev E Stat Nonlin Soft Matter Phys ; 72(3 Pt 1): 031202, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16241419

ABSTRACT

We propose a relation which predicts the low-frequency thermal conductivity of a one-dimensional (1D) system from the thermal conductivity and bulk viscosity at higher frequency. Our theory is based on the assumption that "ballistic" transport by sound waves dominates the heat transport. For a system with equal heat capacities (c(p) = c(v)) this relation is particularly simple. We test the prediction by simulating a chain of particles with quartic interparticle potentials under zero pressure conditions. As the frequency omega --> 0 the theory predicts that the energy current power spectrum diverges as omega(-1/2), not seen in previous simulations. Because we simulate very long chains to long times we do observe the crossover into this regime. The bulk viscosity of a 1D chain has been determined via simulation. It is found to be finite for our system, in contrast to the thermal conductivity which is infinite.

16.
Phys Rev E Stat Nonlin Soft Matter Phys ; 72(2 Pt 1): 021802, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16196592

ABSTRACT

Hole growth measurements were performed using optical microscopy on freely standing polystyrene films at temperatures that were slightly larger than the bulk value of the glass transition temperature T(bulk)g. For the measured range of temperatures, we have observed a transition from linear growth of the hole radius R during the early stages to exponential growth of R at later times. We have characterized this transition as a function of molecular weight 120 x 10(3) < Mw <2240 x 10(3) , film thickness 61 nm

17.
Endocr Res ; 30(4): 647-54, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15666807

ABSTRACT

The ability of adrenocorticotropin (ACTH) to affect gap junctions was examined in adrenal cells in vivo and in vitro. Treatment with ACTH increased the size and number of gap junction plaques on the cell membranes in hypophysectomized animals and in adrenal culture. Intracellular (cytoplasmic) annular gap junctions were observed in cells of the inner adrenal cortical zones and in adrenal cell cultures. To investigate the relationship of annular gap junctions to surface junctions, adrenal cells in culture were transfected with cDNA encoding a green fluorescent protein tagged connexin 43 construct (Cx43-GFP), and subsequently studied by time-lapse video microscopy, immunocytochemistry, and transmission electron microscopy (TEM). Internalization of part or all of a surface gap junction plaque resulted in annular gap junction formation. These studies support the hypothesis that cytoplasmic vesicles, initially described with TEM methods, can result from removal of gap junction plaques from the cell surface. It is suggested that hormones can play a regulatory role in cell-cell communication by influencing the availability of gap junction protein at the cell surface and that hormonally-sensitive processes might serve as a means of altering intercellular communication.


Subject(s)
Adrenal Glands/physiology , Connexins/metabolism , Endocytosis , Adrenal Glands/cytology , Adrenal Glands/metabolism , Animals , Cells, Cultured , Connexin 43/genetics , Female , Gap Junctions/metabolism , Green Fluorescent Proteins/genetics , Immunohistochemistry , Mice , Mice, Inbred C57BL , Microscopy, Electron , Recombinant Fusion Proteins/metabolism , Tissue Distribution , Transfection
18.
Phys Rev Lett ; 90(20): 206101, 2003 May 23.
Article in English | MEDLINE | ID: mdl-12785907

ABSTRACT

We use a seeded supersonic molecular beam to control the kinetic energy of pentacene (C22H14) during deposition and growth on Ag(111). Highly ordered thin films are grown at low substrate temperatures (approximately 200 K) at kinetic energies of a few electron volts, as shown by low energy He diffraction and x-ray reflectivity spectra. In contrast, deposition of thermal molecules yields only amorphous films. Growth at room or higher temperature substrates yields films of poorer quality irrespective of the depositing beam energy. We find that after the first wetting layer is completed, a new ordered phase is formed, whose in-plane lattice spacings match one of the bulk crystal planes. The high quality of the films can be interpreted as the result of local annealing induced by the impact of the impinging high-energy molecules.

19.
Arzneimittelforschung ; 51(10): 814-24, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11715634

ABSTRACT

A series of (indol-3-yl)alkylamides was synthesized and evaluated for analgesic activity. Two N-(pyridin-4-yl)acetamides, compounds 24 and 25, bearing benzyl or 4-fluorobenzyl moieties in 1-position of indole ring exhibited promising analgesic properties (ED50 = 8.1 and 11 mg/kg p.o., respectively), being as potent as the reference drugs flupirtine (CAS 56995-20-1), ibuprofen (CAS 15687-27-1) and diclofenac (CAS 15307-86-5). The two test compounds were tested for their anti-inflammatory activity by carrageenin-induced edema in rat paw test. 4-Fluorobenzyl derivative 25 whose ID50 was 0.085 +/- 0.021 mmol/kg was selected as a lead compound for further pharmacomodulation.


Subject(s)
Alkanes/chemical synthesis , Amides/chemical synthesis , Analgesics, Non-Narcotic/chemical synthesis , Analgesics, Non-Narcotic/pharmacology , Alkanes/pharmacology , Amides/pharmacology , Analgesics, Non-Narcotic/chemistry , Animals , Carrageenan , Edema/chemically induced , Edema/pathology , Indicators and Reagents , Magnetic Resonance Spectroscopy , Pain Measurement/drug effects , Rats , Spectrophotometry, Infrared
20.
J Immunol Methods ; 254(1-2): 99-108, 2001 Aug 01.
Article in English | MEDLINE | ID: mdl-11406156

ABSTRACT

Panels of human antigen-specific T cell clones (TCC) have been established by limiting dilution using Herpesvirus saimiri (HVS) subtype C transformed T cells as antigen presenting cells (APC). They showed antigen-specific proliferation when peripheral blood mononuclear cells (PBMC), HVS-transformed T cells and Epstein Barr Virus transformed lymphoblastoid B cell lines (EBV-LCL) were used as APC. All T cell clones were CD4+ and HLA class II restricted. For a detailed analysis, two panels of T cell clones specific for an epitope located in the N-terminus of the Merozoite Surface Protein 1 (MSP-1) of Plasmodium falciparum were established from the same founder T cell line using either PBMC or HVS-transformed T cells as APC. TCR analysis of the two panels of TCC demonstrated that the same founder cells could be propagated in both culture systems. Furthermore, no difference in the cytokine expression pattern or antigen processing and co-stimulatory requirements was observed between TCC established on PBMC or HVS-transformed T cells. Based on the finding that HVS-transformed T cells can replace PBMC as APC for isolation and propagation of antigen-specific TCC, a protocol was developed and successfully executed, which allows to establish and maintain vaccine-specific T cell clones from 20 ml of blood. This method might be particularly significant in clinical trials of immune intervention strategies.


Subject(s)
Cell Transformation, Viral , Herpesvirus 2, Saimiriine , Leukocytes, Mononuclear/immunology , Recombinant Proteins , T-Lymphocytes/immunology , Amino Acid Sequence , Animals , Antigen Presentation , Cells, Cultured , Clone Cells , Herpesvirus 2, Saimiriine/genetics , Humans , Interferon-gamma/biosynthesis , Interleukin-4/biosynthesis , Leukocytes, Mononuclear/cytology , Malaria Vaccines/immunology , Merozoite Surface Protein 1/immunology , Molecular Sequence Data , Phenotype , Plasmodium falciparum/immunology , Protozoan Proteins/immunology , T-Lymphocytes/cytology , Vaccines, Synthetic/immunology
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