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Designing for Upper Torso and Arm Anatomy
Published in Karen L. LaBat, Karen S. Ryan, Human Body, 2019
Lactation is the formation and secretion of milk. Ramsay, Kent, Hartmann, and Hartmann (2005) studied the lactating breast using ultrasound. They found approximately twice as much glandular tissue as adipose tissue in the lactating breast, but also great variation woman to woman. Milk is said to be “ejected” from the lactiferous ducts and the cavities beneath the nipple, where it has collected, when it is secreted from the breast. Prime, Geddes, and Hartman (2007) report that milk ejection occurs not only during stimulation of the nipple but also reflexively. Conditioning of the milk ejection reflex, sometimes called milk let-down, is common and may be initiated by the mother thinking of her infant, in response to her infant’s cry, or with the infant’s suckling activities.
Engineered Composites for 3D Mammary Tissue Systems
Published in Karen J.L. Burg, Didier Dréau, Timothy Burg, Engineering 3D Tissue Test Systems, 2017
Cheryl T. Gomillion, Chih-Chao Yang, Didier Dréau, Karen J. L. Burg
While a mature network of ductal and lobular structures is formed over time, complete development of the breast tissue does not occur unless pregnancy and childbirth are experienced (Geddes 2007; Wiseman and Werb 2002). Growth of the mammary gland is stimulated by production of progesterone hormones during pregnancy. During pregnancy, significant extension and branching of the breasts ductal system, accompanied by growth of glandular tissue, leads to maximal development of the breast whereby the lobules increase in both size and number. Systemic reproductive hormones, specifically progesterone and prolactin, stimulate the expansion and differentiation of the mammary epithelium into milk-producing cells (Lanigan et al. 2007). Lactation, or the production of milk, is the point where the breast reaches its fully functional capacity due to these functional changes of the glands, which now secrete milk. Following lactation, the breast undergoes involution, a regression of the tissue most notably caused by a collapse or folding of lobular structures and a narrowing of the ducts, which is accompanied by apoptosis and alveolar cell detachment (Macias and Hinck 2012). A similar type of tissue remodeling is observed following menopause when hormones levels, particularly estrogen levels, decrease and glandular tissue atrophies, leaving larger proportions of fat tissue, stromal connective tissue, and skin (Fridriksdottir et al. 2005; Geddes 2007; Gefen and Dilmoney 2007; Parmar and Cunha 2004; Russo and Russo 2004; Villadsen 2005; Wiseman and Werb 2002).
Reproduction, development and work
Published in Chris Winder, Neill Stacey, Occupational Toxicology, 2004
The breasts (or mammary glands) are present in both genders, but only function biologically in females. The main function of the breast is to produce milk for the nourishment of a newborn infant. The breasts develop in females at puberty through stimulation by hormones, especially oestrogens. Anatomically, each breast consists of glandular tissue organised into 15–25 lobes, separated from each other by connective tissue and fat. Slightly below the centre of each breast is a pigmented area, the areola, which surrounds a central protruding nipple. During the process of lactation, milk is secreted from the glandular tissue, and passes along the lactiferous ducts from each lobule, which connects to the nipple.
Genotoxic effects of caffeine in female mice exposed during pregnancy and lactation period and their offspring
Published in Journal of Environmental Science and Health, Part C, 2023
Marina Lummertz Magenis, Pamela Souza de Marcos, Adriani Paganini Damiani, Anderson Ricardo Cantareli da Silva, Luiza Martins Longaretti, Ive Bahia Franca, Juliana Da Silva, Carina Rodrigues Boeck, Vanessa Moraes de Andrade
DNA damage results (% tail intensity) of female mice supplemented with caffeine (CAF 0.3 and CAF 1.0) before copulation and during pregnancy and lactation periods are presented in Figure 2. All females in the before-copulation period (CTR, CAF 0.3, and CAF 1.0) showed similar DNA damage, as they had not started the treatment. During pregnancy, the CAF 0.3 and CAF 1.0 groups showed a significant increase in DNA damage compared to that of the CTR group in the same period, and the values were higher than those reported in the before-copulation period. During the lactation period, a significant increase in DNA damage was observed in the CAF 0.3 and CAF 1.0 groups compared to that of the CTR group. Additionally, when groups that received caffeine were compared, CAF 1.0 group showed increased DNA damage. A significant increase in DNA damage was observed in all groups during pregnancy and lactation, compared to that in the pre-copulation period. Regarding lactation and pregnancy, increased damage was observed in the CTR and CAF 1.0 groups during lactation than in the same groups during pregnancy.
Dietary Intake and Appetite Hormone Patterns among Mothers Participating in the Supplemental Nutrition Assistance Program: A Pilot Study
Published in Journal of Hunger & Environmental Nutrition, 2021
Megan M. Oberle, Eliza Whiteman Kinsey, Terri H. Lipman, Carolyn Cannuscio, Amy Hillier, Virginia A. Stallings
Subjects were recruited by regional advertisement, word-of-mouth, the assistance of several, local nonprofit agencies, and at outpatient pediatric offices in the Philadelphia area. Inclusion criteria included: 1) African-American female heads-of-household with at least one child <18 years old living in the household, 2) participation in SNAP for >1 month, 3) positive screening for food insecurity defined by food security score ≥ 3 on the US Household Food Security Survey,44 4) BMI between 25.0 and 39.9 kg/m2, 5) age 18 to 50 years, 6) premenopausal defined by a history of regular monthly menstrual cycle, and 7) at least one year post-partum. Exclusion criteria were: 1) major organ system illness affecting nutritional intake or metabolism, including type 1 and type 2 diabetes, 2) self-reported eating disorder or pattern of disordered eating, 3) pregnancy or lactation, 5) night shift workers, and 6) non-English speaking. As a pilot study with a small sample size, subjects were recruited as a homogenous study population that would aid in interpretation of leptin concentrations. Leptin concentrations vary by race, age, BMI, and hormonal status.36,45,46 The BMI range was also chosen to aid as overweight and obese subjects have higher leptin concentrations than lean subjects.46
Expression of a recombinant anti-programed cell death 1 antibody in the mammary gland of transgenic mice
Published in Preparative Biochemistry & Biotechnology, 2021
Guihua Gong, Wei Zhang, Liping Xie, Lei Xu, Shu Han, Youjia Hu
During the past two decades, numerous efforts have been made to produce recombinant proteins and monoclonal antibodies in the milk of transgenic animals. The mammary gland expression system is considered to be an ideal bioreactor since milk, as an abundant source of raw materials, is safe, readily available and easily accepted by the public.[19] It was reported that four caseins (αs1, αs2, β and κ)[20] and two serum proteins (β- lactoglobulin and α-lactoalbumin)[21] were mainly secreted by ruminants. The genes encoding these proteins are specifically expressed at high levels in the mammary gland during the pregnancy and lactation.[22] Thus, promoters and regulatory regions of such genes were used to direct the exogenous gene expression in the mammary gland of transgenic animals.[23]