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1.
Gynecol Obstet Fertil Senol ; 49(12): 907-912, 2021 12.
Article in French | MEDLINE | ID: mdl-34091080

ABSTRACT

OBJECTIVES: Breast cancer is the leading cancer in women worldwide with about 2 million new cases and 685,000 deaths each year. Mammography is the most widely used screening and diagnostic method. Currently, digital technologies advances facilitate the development of connected and portable devices. To overcome some of the disadvantages of mammography (breast compression, difficulty in analyzing dense breasts, radiation, limited accessibility in some countries, etc.), portable devices, conventionally known as connected bras (CB), have been created to offer an alternative method to mammography. The objective of our review was to list all the published CBs in order to know their main characteristics, their potential indications and their possible limitations. METHOD: A bibliographical search in the PUBMED database selecting only articles written in French or English, between 2011 and 2020, found 7 CBs under development. RESULTS: These CBs use thermal, ultrasonic and impedance sensors. Their advantages are an absence of irradiation, an absence of breast compression and a flexibility of use (outside an X-ray cabinet). Mammary gland analysis times vary, depending on the device, between 30min and 24h. They are all connected to data transmission systems and models that analyze the results. DISCUSSION AND CONCLUSION: These CBs are mostly still undergoing clinical validation (only [iTBra] has been evaluated in a clinical trial) and require evaluation steps that will eventually allow their future use for breast cancer detection in high-risk women, particularly in women with dense breasts and in women between screening waves.


Subject(s)
Breast Neoplasms , Breast , Breast Neoplasms/diagnosis , Early Detection of Cancer/methods , Female , Humans , Mammography/methods , Mass Screening/methods
2.
J Med Eng Technol ; 43(5): 305-322, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31545114

ABSTRACT

Breast cancer is a disease that threat many women's life, thus, the early and accurate detection play a key role in reducing the mortality rate. Mammography stands as the reference technique for breast cancer screening; nevertheless, many countries still lack access to mammograms due to economic, social and cultural issues. Last advances in computational tools, infra-red cameras and devices for bio-impedance quantification allowed the development of parallel techniques like, thermography, infra-red imaging and electrical impedance tomography, these being faster, reliable and cheaper. In the last decades, these have been considered as complement procedures for breast cancer diagnosis, where many studies concluded that false positive and false negative rates are greatly reduced. This work aims to review the last breakthroughs about the three above-mentioned techniques describing the benefits of mixing several computational skills to obtain a better global performance. In addition, we provide a comparison between several machine learning techniques applied to breast cancer diagnosis going from logistic regression, decision trees and random forest to artificial, deep and convolutional neural networks. Finally, it is mentioned several recommendations for 3D breast simulations, pre-processing techniques, biomedical devices in the research field, prediction of tumour location and size.


Subject(s)
Breast Neoplasms/diagnosis , Early Detection of Cancer/methods , Electric Impedance , Female , Humans , Thermography , Tomography
3.
Pediatr Res ; 14(1): 67-9, 1980 Jan.
Article in English | MEDLINE | ID: mdl-7360523

ABSTRACT

Testosterone metabolism and dihydrotestosterone (DHT) receptor activity were studied in fibroblasts cultured from genital and non-genital tissues of 8- to 22-week old human fetuses. As early as the eighth week of gestation, DHT receptor activity was detected in non-genital skin. The binding capacity (Bmax) was greater in genital skin fibroblasts (mean +/- SD = 474 +/- 32 moles x 10--18/micrograms DNA) than non-genital skin (mean +/- SD = 124 +/- 42 moles x 10(-18)/micrograms DNA). DHT receptor binding (Bmax) was found in fibroblasts derived from testes (112 moles x 10(-18)/micrograms DNA), but not intestine (less than 10 moles x 10(-18)/micrograms DNA). The DHT receptor activity of fetal skin fibroblasts of genital origin was similar to that of fibroblasts derived from the foreskin of normal newborns. DHT receptors from fetal and newborn fibroblast cultures had similar sedimentation coefficients in sucrose density gradient centrifugation, but there were small differences in their relative affinities for 17 beta-estradiol and cyproterone. Low, but detectable 5 alpha-reductase activity was observed at 8 weeks gestation in non-genital skin fibroblasts and was present in fibroblasts from a variety of tissues of older fetuses, including testes, kidneys and lungs. The highest 5 alpha-reductase activity of 210 pg/hour/micrograms DNA was found in fibroblasts cultured from clitoral tissue from a 10-week old fetus. In all but one specimen, the 5 alpha-reduced products were either DHT or 5 alpha-androstanedione. The demonstration of 5 alpha-reductase activity and specific DHT receptors in fetal tissues suggests that the intracellular mechanism for androgen action is present in the fetus, similar to that after birth.


Subject(s)
Dihydrotestosterone/metabolism , Fetus/metabolism , Receptors, Androgen/metabolism , Receptors, Steroid/metabolism , 3-Oxo-5-alpha-Steroid 4-Dehydrogenase/metabolism , Binding, Competitive , Cells, Cultured , Female , Fibroblasts/metabolism , Genitalia/embryology , Humans , Kidney/embryology , Lung/embryology , Male , Skin/embryology , Testosterone/metabolism
5.
Steroids ; 33(3): 277-85, 1979 Mar.
Article in English | MEDLINE | ID: mdl-442123

ABSTRACT

The effects of 5,10-secoestra-4,5-diene-3,10,17-trione (Compound I) and 5,10-seco-19-norpregna-4,5-diene,3,10,20-trione (Compound II) on the 5 alpha-reductase activity and on the androgen receptors of normal human sex skin fibroblasts were investigated. The Vmax and Km of the transformation of testosterone to 5 alpha-reduced products was 387 pg/microgram DNA/30 min and 234 X 10(-9)M, respectively. When the inhibitors were introduced in the assay, the 5 alpha-reductase activity was markedly reduced, Compound I being a less potent inhibitor than Compound II. At 15 min, the inhibition was greater than at 30 and 60 min. The Ki for Compound I was 1.60 x 10(-6)M with a Vmax of 83 to 553 pg/microgram DNA/30 min. For Compound II, the Ki was 0.53 x 10(-6)M with a Vmax of 70 to 340 pg/microgram DNA/30 min. The inhibition was of the noncompetitive type. Studies with androgen receptors showed that Compound I had a lower affinity for the receptors than Compound II. The ID50 for 3H-DHT and 3H-T for Compound I were 42.9 x 10(-7)M and 8.6 x 10(-7)M, respectively, whereas for Compound II, they were 10.6 x 10(-7)M and 4.8 x 10(-7)M.


Subject(s)
5-alpha Reductase Inhibitors , Fibroblasts/enzymology , Oxidoreductases/antagonists & inhibitors , Secosteroids/pharmacology , Binding, Competitive , Dihydrotestosterone/metabolism , Humans , Infant, Newborn , Kinetics , Male , Penis/enzymology , Receptors, Androgen/metabolism , Testosterone/metabolism
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