The mammary gland (MG) is one of a few organs that undergoes most of its growth after birth. Much of this development occurs concurrently with specific reproductive states, such that the ultimate goal of milk synthesis and secretion is coordinated with the nutritional requirements of the neonate. Central to the reproductive-MG axis is its endocrine regulation, and pivotal to this regulation is the ovarian secretion of estrogen (E). Indeed, it is widely accepted that estrogens are essential for growth of the MG to occur, both for ductal elongation during puberty and for alveolar development during gestation. As the factors regulating MG development continually come to light from the fields of developmental biology, lactation physiology, and breast cancer research, a growing body of evidence serves as a reminder that the MG are not as exclusively dependent on estrogens as might have been thought. The objective of this review is to summarize the state of information regarding our understanding of how estrogen (E) has been implicated as the key regulator of MG development, and to highlight some of the alternative E-independent mechanisms that have been discovered. In particular, we review our findings that dietary trans-10,cis-12 conjugated linoleic acid promotes ductal elongation and that the combination of progesterone (P) and prolactin (PRL) can stimulate branching morphogenesis in the absence of E. Ultimately, these examples stand as a healthy challenge to the question of just how important estrogens are for MG development. Answers to this question, in turn, increase our understanding of MG development across all mammals and the ways in which it can affect milk production.

When learners improve, the temporal change in performance carries information about progress; we know we “got the hang of it” after succeeding on a task we used to fail at. Building on prior work investigating older children's ability to track their performance over time, here we ask whether two-year-olds can reason about the temporal pattern of their performance outcomes. Children in the Improvement condition experienced 3 failures followed by 3 successes (FFFSSS) whereas children in the Stochastic condition experienced the same number of failures and successes in a seemingly random sequence (SSFFSF). When asked which toy they wanted to show their parent, children were more likely to select the Test Toy over a Control Toy when the temporal sequence of their performance suggested improvement than when it appeared to be random. By reasoning about their own performance over time, even young children can make informed choices about their future actions.

Diaphanospondylodysostosis (DSD) is a rare skeletal dysplasia syndrome resulting from disordered mesenchymal differentiation. Children with DSD generally die in utero or during the first month of life from severe thoracic insufficiency syndrome. An association of DSD with nephroblastomatosis has been observed, but the natural history of such nephroblastomatosis remains poorly characterized due to the rarity of the underlying condition. We describe a patient with DSD who developed bilateral hyperplastic nephroblastomatosis that ultimately evolved into therapy-resistant anaplastic Wilms tumor (nephroblastoma).

Liposarcoma is a soft-tissue sarcoma typically seen in adults. It is extremely rare in children. It most often occurs in the extremities or in the retroperitoneum. We present a very rare case of an anterior mediastinal liposarcoma of the pleomorphic subtype in a 17-year-old girl, along with radiological and pathological correlation. The location, patient age and histological subtype are exceedingly uncommon for this tumor.

Objective

This study examines associations between the risk of sleep apnea and abdominal obesity (assessed by waist-to-hip ratio (WHR)) and general obesity (assessed by body mass index (BMI)) in a sample of Chinese and Korean American immigrants.

Methods

The dataset included Chinese and Korean participants aged 50-75 who were recruited from primary care physicians' clinics from April 2018 to June 2020 in the Baltimore-Washington D.C. Metropolitan area (n = 394). Abdominal obesity was determined if WHR ≥ 0.9 in men and WHR ≥ 0.85 in women. General obesity was determined if BMI ≥ 30. The risk of sleep apnea was determined by using the Berlin questionnaire. Poisson regression models examined associations between sleep apnea risk and obesity. Models controlled for socio-demographic risk factors.

Results

Twelve percent of the study participants were classified as a high risk for sleep apnea, and 75% had abdominal obesity whereas 6.4% had general obesity. High risk of sleep apnea was positively associated with abdominal obesity (PR = 1.31, 95% CI: 1.17-1.47) and general obesity (PR = 2.19, 95% CI: 0.90-5.32), marginally significant at p < 0.1).

Conclusions

Chinese and Korean immigrants living in the USA who are at high risk of sleep apnea have higher abdominal obesity, even after accounting for sociodemographic characteristics. Abdominal obesity may be a better indicator than general obesity when examining the risk of sleep apnea among Asian Americans.

Information on clinical trial

Name: Screening To Prevent ColoRectal Cancer (STOP CRC) among At-Risk Asian American Primary Care Patients NCT Number: NCT03481296; Date of registration: March 29, 2018 URL: https://clinicaltrials.gov/ct2/show/NCT03481296?term=Sunmin+Lee&draw=2&rank=1.

Study objectives

This study aims to examine associations between acculturative stress-defined as the psychological impact, or stress reaction, of adapting to a new cultural context-and self-reported sleep outcomes among Chinese and Korean immigrants in the United States.

Methods

In this cross-sectional study, acculturative stress was assessed using a 9-item scale, and sleep disturbance was measured using the 8-item scale. Sleep duration was self-reported. Poisson and linear regression analyses were conducted to examine the associations between acculturative stress, sleep disturbance, and sleep duration.

Results

Our sample consists of 400 participants (females: 52%, Chinese: 50%, Koreans: 50%, the mean of age = 58.4). 81.8% of them were classified as having no sleep disturbance, whereas 18.2% were classified as having sleep disturbance. Poisson models revealed that greater acculturative stress was associated with a higher prevalence of sleep disturbance (Prevalence Ratio (PR): 1.18, 95% confidence interval (CI): 1.06% to 1.31%). In linear models, a one-unit increase in acculturative stress was associated with 0.08 hr less sleep (p < .05). Interaction tests indicated effect modification for sleep disturbance by sex and ethnic identity: only women had a significant association between acculturative stress and sleep disturbance (PR: 1.30; 95% CI: 1.13 to 1.49), while the association was significant for individuals identifying as "very Asian" (PR: 1.21; 95% CI: 1.08 to 1.35), but not for those identifying as "mostly Asian" or "bicultural/western".

Conclusions

If findings are replicated, we suggest developing intervention programs for Asian immigrants to minimize acculturative stress and bolster protective factors that decrease the risk for poor sleep outcomes.Information on Clinical Trial: Name: Screening To Prevent ColoRectal Cancer (STOP CRC) among At-Risk Asian American Primary Care Patients NCT Number: NCT03481296 URL: https://clinicaltrials.gov/ct2/show/NCT03481296?term=Sunmin+Lee&draw=2&rank=1.

The actin cytoskeleton is regulated by factors that influence polymer assembly, disassembly, and network rearrangement. Drugs that inhibit these events have been used to test the role of actin dynamics in a wide range of cellular processes. Previous methods of arresting actin rearrangements take minutes to act and work well in some contexts, but can lead to significant actin reorganization in cells with rapid actin dynamics, such as neutrophils. In this paper, we report a pharmacological cocktail that not only arrests actin dynamics but also preserves the structure of the existing actin network in neutrophil-like HL-60 cells, human fibrosarcoma HT1080 cells, and mouse NIH 3T3 fibroblast cells. Our cocktail induces an arrest of actin dynamics that initiates within seconds and persists for longer than 10 min, during which time cells maintain their responsivity to external stimuli. With this cocktail, we demonstrate that actin dynamics, and not simply morphological polarity or actin accumulation at the leading edge, are required for the spatial persistence of Rac activation in HL-60 cells. Our drug combination preserves the structure of the existing cytoskeleton while blocking actin assembly, disassembly, and rearrangement, and should prove useful for investigating the role of actin dynamics in a wide range of cellular signaling contexts.

Ileal neuroendocrine tumors (NETs) represent the most common neoplasm of the small intestine. Although up to 50% of patients with ileal NETs are diagnosed with multifocal disease, the mechanisms by which multifocal ileal NETs arise are not yet understood. In this study, we analyzed genome-wide sequencing data to examine patterns of copy number variation in 40 synchronous primary ileal NETs derived from three patients. Chromosome (chr) 18 loss of heterozygosity (LOH) was the most frequent copy number alteration identified; however, not all primary tumors from the same patient had evidence of this LOH. Our data revealed three distinct patterns of chr18 allelic loss, indicating that primary tumors from the same patient can present different LOH patterns including retention of either parental allele. In conclusion, our results are consistent with the model that multifocal ileal NETs originate independently. In addition, they suggest that there is no specific germline allele on chr18 that is the target of somatic LOH.

Abstract Background Sterile syringe access is a critical component of HIV prevention programs. Although retail pharmacies provide convenient outlets for syringe access, injection drug users (IDUs) may encounter barriers to syringe purchase even where purchase without a prescription is legal. We sought to obtain an objective measure of syringe access in Tijuana, Mexico, where IDUs report being denied or overcharged for syringes at pharmacies. Methods Trained "mystery shoppers" attempted to buy a 1 cc insulin syringe according to a predetermined script at all retail pharmacies in three Tijuana neighborhoods. The same pharmacies were surveyed by telephone regarding their syringe sales policies. Data on purchase attempts were analyzed using basic statistics to obtain an objective measure of syringe access and compared with data on stated sales policies to ascertain consistency. Results Only 46 (28.4%) of 162 syringe purchase attempts were successful. Leading reasons for unsuccessful attempts were being told that the pharmacy didn't sell syringes (35.3%), there were no syringes in stock (31.0%), or a prescription was required (20.7%). Of 136 pharmacies also surveyed by telephone, a majority (88.2%) reported selling syringes but only one-third (32.5%) had a successful mystery shopper purchase; the majority of unsuccessful purchases were attributed to being told the pharmacy didn't sell syringes. There was similar discordance regarding prescription policies: 74 pharmacies said in the telephone survey that they did not require a prescription for syringes, yet 10 of these pharmacies asked the mystery shopper for a prescription. Conclusions IDUs in Tijuana have limited access to syringes through retail pharmacies and policies and practices regarding syringe sales are inconsistent. Reasons for these restrictive and inconsistent practices must be identified and addressed to expand syringe access, reduce syringe sharing and prevent HIV transmission.