Primary human breast epithelial cells isolated from patient reduction mammoplasty tissues were seeded into 3D hydrogels. The hydrogel scaffolds were composed of extracellular proteins and carbohydrates present in human breast tissue and were cultured in serum-free medium containing only defined components. The physical properties of these hydrogels were determined using atomic force microscopy. Tissue growth was monitored over time using bright-field and fluorescence microscopy, and maturation was assessed using morphological metrics and by immunostaining for markers of stem cells and differentiated cell types. The hydrogel tissues were also studied by fabricating physical models from confocal images using a 3D printer.
Images were captured using a Zeiss LSM 700 (immunofluorescence; Zeiss Microscopy, Thornwood, NY, USA), a Zeiss Axiophot (immunohistochemistry; Zeiss Microscopy), and a Nikon TE2000 (Nikon Instruments, Melville, NY, USA) with a heated stage and 5 % CO2 (time lapse).
Extracts of the pituitary gland contain factors important for mammary development, including growth hormone, fibroblast growth factors, and follicle-stimulating hormone [32, 33]. Consistent with this, addition of pituitary extracts to the ECM hydrogels caused a significant increase in both secondary and tertiary ductal branching of the expanded breast tissues (Fig. 1e). Moreover, addition of both pituitary extract and prolactin further stimulated lobular expansion with a fourfold increase in lobular volume accompanied by the formation of large lipid droplets that were visible upon hematoxylin and eosin staining (Fig. 1e and f, Additional file 2: Figure S5).
Time-lapse microscopy provided additional insights into the relationship between these leader cells and ductal elongation. Ductal elongation was always preceded by a transient extension of leader cells that physically engaged with and deformed the ECM (Fig. 4d and e, Additional file 4: Movie S2, Additional file 7: Movie S5). At times, the force of this interaction between leader cells and the matrix caused them to break away from the ducts and become isolated in the matrix (Additional file 4: Movie S2). The direction in which the leader cells extended was always the direction of the next wave of ductal elongation. When the direction in which the leader cells emanated was different from the previous direction of elongation, the ducts reoriented in the new direction specified by the leader cells before the next wave of elongation (Fig. 4f, Additional file 8: Movie S6). This ductal reorientation appeared to be induced by the collective rotation of cells in the lobule, which occurred before ductal elongation (Additional file 8: Movie S6). After the ducts reoriented, they elongated for a period of time, after which the elongation ceased. After ductal elongation ceased, new leader cells emanated from the ductal tips to initiate the next cycle of elongation.
Twenty-four-hour time-lapse movie of an organoid growing in hydrogel. Still frames from this movie are depicted in Fig. 4d. At the outset of the movie, the organoid had been grown for 8 days. Images were captured every 10 minutes. Frame rate: eight frames per second. (AVI 19903 kb)
To date, several studies have used AI methods for embryo assessment or blastocyst grading. The published AI models that aimed to offer a prediction of embryo outcome utilized either TLM images17,21 or videos22 of D5/6 blastocysts to predict pregnancy or live birth, so the course and endpoints are different with our study. In consideration of the fact that a successful pregnancy or live birth is a combined consequence of embryo potential, transfer time, and maternal conditions27, our study chose blastocyst as an endpoint, which not only aims to predict the developmental potential of embryos but also reduce confounding factors from maternal conditions and other external factors28. Hence, by utilizing a large amount of TLM videos, an objective and automatic approach was developed for predicting the developmental potential of embryos, which may represent a great breakthrough in employing deep learning in TLM video assessment.
On the basis of the cell-counting algorithm, the LSTM network was used to develop the temporal stream model. The LSTM network is a special type of recurrent neural network (RNN) that is capable of learning the forward and backward dependencies among the frames in time series data36. In the field of medical science, this network has demonstrated its superiority in dealing with temporal information. Here, we employed the LSTM to learn the cell stage information output from cell-counting model in consecutive frames, and the morphokinetic parameters of embryo development were subsequently obtained. The ensemble of the cell-counting algorithm and LSTM network was a bright spot in our modeling process, yielding significant improvements than exclusively using LSTM to directly learn the features from the CNN network (our own experimental data in STEM: accuracy 76.9% vs. 61%, sensitivity 84.7% vs. 85%, specificity 64.7% vs. 24%).
We study stem cells and the signals that orchestrate cell fate specification, both during physiological tissue development and homeostasis as well as in tumours. We use an interdisciplinary approach combining in vivo clonal analysis by lineage tracing with time-lapse analysis of 3D organotypic cultures and intravital imaging, whole mount immunofluorescence, barcoding and transcriptomic analyses and mathematical modelling of clonal dynamics. Our projects use Notch expression and activity as tools to characterize stem/progenitor cells, but are also aimed at revealing if mechanistically Notch signals can change the fate of normal and cancer stem cells.
Puberty is the time when your body grows from a child's to an adult's. During puberty, children's external genitalia begin development and show secondary sex characteristics. The normal age of puberty is between 7 and 13 for girls and 9 and 15 for boys. Some adolescents do not start their sexual development at the usual age. They do not show any signs of body changes. This is called delayed puberty. The delay in some cases represents a normal variation, but other causes are some kind of diseases, such as diabetes, inflammatory bowel disease, kidney disease, cystic fibrosis, mumps, anemia, and genetic diseases. Tests such as hormone level tests and bone age X-ray test, even cranial CT or MRI and chromosomal analysis may help find the causes of delayed puberty. Treatment and prognosis of delayed puberty depend on the cause.
The goal of feminizing hormone therapy is the development of female secondary sex characteristics, and suppression/minimization of male secondary sex characteristics. General effects include breast development (usually to Tanner stage 2 or 3), a redistribution of facial and body subcutaneous fat, reduction of muscle mass, reduction of body hair (and to a lesser extent, facial hair), change in sweat and odor patterns, and arrest and possible reversal of scalp hair loss. Sexual and gonadal effects include reduction in erectile function, changes in libido, reduced or absent sperm count and ejaculatory fluid, and reduced testicular size. Feminizing hormone therapy also brings about changes in emotional and social functioning. The general approach of therapy is to combine an estrogen with an androgen blocker, and in some cases a progestogen.
Antiandrogens can also be used alone to bring reduced masculinization and minimal breast development, or in those patients who wish to first explore reduced testosterone levels alone, or in those with contraindications to estrogen therapy. In the absence of estrogen replacement, some patients may have unpleasant symptoms of hot flashes and low mood or energy. Long term full androgen blockade without hormone replacement in men who have undergone treatment for prostate cancer results in bone loss, and this effect would also be expected to occur in transgender individuals. In addition to titrating dosing to both clinical effect and testosterone levels as guided by patient goals, monitoring hormone levels to insure suppressed gonadotropins (luteinizing hormone [LH] and follicle stimulating hormone [FSH]) levels may serve as a surrogate marker to indicate adequate sex hormone levels for maintaining bone density in such patients (Grading: T O W).
Progestogens: There have been no well-designed studies of the role of progestogens in feminizing hormone regimens. Many transgender women and providers alike report an anecdotal improved breast and/or areolar development, mood, or libido with the use of progestogens.[17,18] There is no evidence to suggest that using progestogens in the setting of transgender care are harmful. In reality some patients may respond favorably to progestogens while others may find negative effects on mood. While progestogens have some anti-androgen effect through central blockade of gonadotropins, there is also a theoretical risk of a direct androgenizing effect of progestogens. This class includes micronized bioidentical progesterone (Prometrium) as well as a number of synthetic progestins. The most commonly used synthetic progestin in the context of transgender care is the oral medroxyprogesterone acetate (Provera).
While concerns exist from the Women's Health Initiative (WHI) regarding risks of cardiovascular disease and breast cancer in the setting of medroxyprogesterone use, these concerns likely do not apply in the context of transgender care for several reasons. First, the transgender women may be at lower risk of breast cancer than non-transgender women. Second, this arm of the WHI involved the use of conjugated equine estrogens in combination with medroxyprogesterone in a sample of menopausal women, some of whom were as long as 10 years post-menopausal at the time of hormone initiation. Third, while statistically significant, the clinical significance of the findings in the WHI was subtle