Patterns of Gene Expression from Human Costal Cartilage in Relation to the Chest Wall Deformity Pectus Carinatum

Cartilage deformities within the human chest wall, specifically pectus excavatum (PE) and pectus carinatum (PC) are common (1/400-1/1000) and yet, despite their clinical significance, are some of the least studied disorders pertaining to cartilage [1]. The costal cartilage connecting false ribs 8-10 to the sternum is often abnormally grown and can lead to formation of a severely sunken funnel chest (PE) or push outwards to form a pigeon chest (PC). Both conditions can have impact on the diaphragm, heart, lungs, and psychological function. An established ratio of PE and PC in males to females is 4:1, indicating a sex-linked male prevalence to these disorders. In this study, costal cartilage samples from patients with PC were examined in comparison to samples from control cartilage, i.e., from those who did not have other known chondral dysplasias. We hypothesized that significant differences in expression of key cartilaginous related genes between the PC patients and an age-matched control would be observed. The genes of interest included COL1α1, COL2α1, SOX9, ACAN, compared to a housekeeping gene, Actin (ACTβ). We also analyzed expression of the small leucine-rich repeat proteoglycans (SLRPs) BGN and DCN. which bind to collagen fibers located in the extracellular matrix. The potent transcription factor of chondrogenesis studied was TGFβ1, as well as several other genes [2]. Our data revealed high levels of gene expression for DCN and COL2α1 in all samples of PC costal cartilage compared to an age-matched control. The male prevalence of these disorders was investigated in relation to the following X-linked cartilaginous related genes: NYX TIMP-1, BGN, and CACNA1F. The BGN SLRP did not exhibit significant differences in either patients or controls. The TIMP-1 gene was expressed with significant differences between patients and the age-matched control. The gene expression ratios of COL2α1/COL1α1, ACAN/COL2α1 and COL2α1/ACAN were also lower than published values reported for articular chondrocytes, fibrocartilage of intervertebral discs and rat chondrosarcomas. However, in our study, many ratios were established for the first time in this type of PC tissue. There were observed changes in patterns of gene expression of costal cartilage from the control samples age, 23 weeks to 81 years old, indicating the importance of age-matched controls. For future studies, our data can be compared to similar experiments on the true ribs and how the costal cartilage of these ribs may change in terms of gene expression with age, and which gene expression changes are important for adolescents with PC and or PE. Also, an investigation of X-linked gene expression in female cartilage is needed to better understand the etiology of PC or PE in relation to X-inactivation. Better understanding of the biology of these disorders will help in identifying causes and sequelae, leading to modified therapeutic options, particularly for those patients who do not respond well to chest wall surgical repair. This study provides new baseline patterns of gene expression in the context of the biology of costal cartilage and is a major contribution in the cartilage biology field

Probing Nanoparticle Interactions in Cell Culture Media

Nanoparticle research is often performed in vitro with little emphasis on the potential role of cell culture medium. In this study, gold nanoparticle interactions with cell culture medium and two cancer cell lines (human T-cell leukemia Jurkat and human pancreatic carcinoma PANC1) were investigated. Gold nanoparticles of 10, 25, 50, and 100 nm in diameter at fixed mass concentration were tested. Size distributions and zeta potentials of gold nanoparticles suspended in deionized (DI) water and Dulbecco\u27s Modified Eagle\u27s Media (DMEM) supplemented with fetal calf serum (FCS) were measured using dynamic light scattering (DLS) technique. In DI water, particle size distributions exhibited peaks around their nominal diameters. However, the gold nanoparticles suspended in DMEM supplemented with FCS formed complexes around 100 nm, regardless of their nominal sizes. The DLS and UV-vis spectroscopy results indicate gold nanoparticle agglomeration in DMEM that is not supplemented by FCS. The zeta potential results indicate that protein rich FCS increases the dispersion quality of gold nanoparticle suspensions through steric effects. Cellular uptake of 25 and 50 nm gold nanoparticles by Jurkat and PANC1 cell lines were investigated using inductively coupled plasma-mass spectroscopy. The intracellular gold level of PANC1 cells was higher than that of Jurkat cells, where 50 nm particles enter cells at faster rates than the 25 nm particles

Maternal Nutrition and Meat Quality of Progeny

The concept of fetal programming is based on the idea that nutritional status and environmental conditions encountered by the dam during pregnancy can have lifetime impacts on her offspring. These changes in the gestational environment have been shown to influence fetal development and subsequent growth performance, carcass composition, and meat quality characteristics. Beef fetuses can be particularly prone to experiencing variations in the maternal environment during development owing to a relatively long duration of pregnancy potentially exposing the dam to environmental temperature stress and/or seasonal conditions that can compromise feed quality or quantity. If feed is limited or forage conditions are poor, a maternal deficiency in protein and/or energy can occur as well as fluctuations in body condition of the dam. As a result, the fetus may receive inadequate levels of nutrients, potentially altering fetal development. There are critical windows of development during each stage of gestation in which various tissues, organs, and metabolic systems may be impacted. Skeletal muscle and adipose tissue are particularly vulnerable to alterations in the gestational environment because of their low priority for nutrients relative to vital organs and systems during development. The timing and severity of the environmental event or stressor as well as the ability of the dam to buffer negative effects to the fetus will dictate the developmental response. Much of the current research is focused on the influence of specific nutrients and timing of nutritional treatments on offspring carcass composition and meat quality, with the goal of informing strategies that will ultimately allow for the use of maternal nutritional management as a tool to optimize performance and meat quality of offspring

Comparison of Winter Cow Feeding Strategies on Offspring Carcass Characteristics and Meat Quality

Objective The objective of this research was to investigate effects of maternal prepartum dietary energy source (forage vs. concentrate) during mid and late gestation on carcass composition, and meat quality of offspring.Study Description Angus-based cows from 2 sources [n = 129 from SDSU (Experiment 1) and n = 70 from North Dakota State University (Experiment 2)] were stratified by body weight and age and placed into two treatment groups at a drylot facility during mid- and late-gestation: Concentrate (dams fed a concentrate-based diet) or Forage (dams fed a forage-based diet). Calves were finished and carcass data was collected. Striploins were collected for meat quality evaluation

Influence of Maternal Carbohydrate Source (Concentrate-Based vs. Forage-Based) on Growth Performance, Carcass Characteristics, and Meat Quality of Progeny

The objective of this research was to investigate the influence of maternal prepartum dietary carbohydrate source on growth performance, carcass characteristics, and meat quality of offspring. Angus-based cows were assigned to either a concentrate-based diet or forage-based diet during mid- and late-gestation. A subset of calves was selected for evaluation of progeny performance. Dry matter intake (DMI), body weight (BW), average daily gain (ADG), gain to feed (G:F), and ultrasound measurements (muscle depth, back fat thickness, and intramuscular fat) were assessed during the feeding period. Carcass measurements were recorded, and striploins were collected for Warner-Bratzler shear force (WBSF), trained sensory panel, crude fat determination and fatty acid profile. Maternal dietary treatment did not influence (p > 0.05) offspring BW, DMI, ultrasound measurements, percent moisture, crude fat, WBSF, or consumer sensory responses. The forage treatment tended to have decreased (p = 0.06) 12th rib backfat compared to the concentrate treatment and tended to have lower (p = 0.08) yield grades. The concentrate treatment had increased (p < 0.05) a* and b* values compared to the forage treatment. These data suggest variation in maternal diets applied in this study during mid- and late-gestation has limited influence on progeny performance