Growth and development symposium: Stem and progenitor cells in animal growth: The regulation of beef quality by resident progenitor cells

© The Author(s) 2019. Published by Oxford University Press on behalf of the American Society of Animal Science. All rights reserved. The intramuscular adipose tissue deposition in the skeletal muscle of beef cattle is a highly desired trait essential for high-quality beef. In contrast, the excessive accumulation of crosslinked collagen in intramuscular connective tissue contributes to beef toughness. Recent studies revealed that adipose tissue and connective tissue share an embryonic origin in mice and may be derived from a common immediate bipotent precursor in mice and humans. Having the same linkages in the development of adipose tissue and connective tissue in beef, the lineage commitment and differentiation of progenitor cells giving rise to these tissues may directly affect beef quality. It has been shown that these processes are regulated by some key transcription regulators and are subjective to epigenetic modifications such as DNA methylation, histone modifications, and microRNAs. Continued exploration of relevant regulatory pathways is very important for the identification of mechanisms influencing meat quality and the development of proper management strategies for beef quality improvement

Microenvironmental Influence on Pre-Clinical Activity of Polo-Like Kinase Inhibition in Multiple Myeloma: Implications for Clinical Translation

Polo-like kinases (PLKs) play an important role in cell cycle progression, checkpoint control and mitosis. The high mitotic index and chromosomal instability of advanced cancers suggest that PLK inhibitors may be an attractive therapeutic option for presently incurable advanced neoplasias with systemic involvement, such as multiple myeloma (MM). We studied the PLK 1, 2, 3 inhibitor BI 2536 and observed potent (IC50<40 nM) and rapid (commitment to cell death <24 hrs) in vitro activity against MM cells in isolation, as well as in vivo activity against a traditional subcutaneous xenograft mouse model. Tumor cells in MM patients, however, don't exist in isolation, but reside in and interact with the bone microenvironment. Therefore conventional in vitro and in vivo preclinical assays don't take into account how interactions between MM cells and the bone microenvironment can potentially confer drug resistance. To probe this question, we performed tumor cell compartment-specific bioluminescence imaging assays to compare the preclinical anti-MM activity of BI 2536 in vitro in the presence vs. absence of stromal cells or osteoclasts. We observed that the presence of these bone marrow non-malignant cells led to decreased anti-MM activity of BI 2536. We further validated these results in an orthotopic in vivo mouse model of diffuse MM bone lesions where tumor cells interact with non-malignant cells of the bone microenvironment. We again observed that BI 2536 had decreased activity in this in vivo model of tumor-bone microenvironment interactions highlighting that, despite BI 2536's promising activity in conventional assays, its lack of activity in microenvironmental models raises concerns for its clinical development for MM. More broadly, preclinical drug testing in the absence of relevant tumor microenvironment interactions may overestimate potential clinical activity, thus explaining at least in part the gap between preclinical vs. clinical efficacy in MM and other cancers

Personal hygiene

© 2005 by Taylor & Francis Group, LLC. More than 215 million cases of infectious disease are caused by foodborne illness in industrialized countries each year, but the true incidence is difficult to determine because actual illness cases are probably underreported (1,2). The five major risk factors related to employee behaviors and preparation practices in retail and food service establishments that have been identified as contributing to foodborne illness are improper holding temperatures, inadequate cooking, contaminated equipment, food from unsafe sources, and poor personal hygiene (3). The five key public health interventions to protect consumer health are demonstration of knowledge, employee health controls, controlling hands as a vehicle of contamination, time and temperature parameters for controlling pathogens, and the consumer advisory notices (3). Three of the important interventions rely directly or indirectly on the employee and individual personal hygiene

Where is MAP Going? A review and future potential of modified atmosphere packaging for meat

Modified atmosphere packaging (MAP) is the removal and/or replacement of the atmosphere surrounding the product before sealing in vapor-barrier materials. While technically different, many forms of MAP are also case-ready packaging, where meat is cut and packaged at a centralized location for transport to and display at a retail store. Most of the shelf life properties of meat are extended by use of MAP, but anoxic forms of MAP without carbon monoxide (CO) do not provide bloomed red meat color and MAP with oxygen (O2) may promote oxidation of lipids and pigments. Advances in plastic materials and equipment have propelled advances in MAP, but other technological and logistical considerations are needed for successful MAP systems for raw chilled fresh meat. Current MAP options of air-permeable overwrapped trays in master packs, low O2 formats of shrunk film vacuum packaging (VP) or MAP with carbon dioxide (CO2) and nitrogen (N2) and their peelable barrier film derivatives, and high O2 MAP each have advantages and disadvantages. Packaging technology innovations and ingenuity will continue to provide MAP that is consumer oriented, product enhancing, environmentally responsive, and cost effective, but continued research and development by the scientific and industry sectors will be needed. © 2008 Elsevier Ltd. All rights reserved

Modified Atmosphere Packaging

© Springer Nature Switzerland AG 2020. Modified atmosphere packaging (MAP) is the alteration of the initial gaseous environment that surrounds the food so that the resulting environment affects the metabolic processes of the food and food-borne microorganisms. The changes in the package atmosphere and resulting product characteristics can be influenced by the food itself, the gaseous environment around the food, the packaging materials, and external factors such as temperature, light, handling environment, and contamination. Vacuum packaging and gaseous MAP are the two major forms of MAP. The selection of the packaging materials, equipment as well as gases are dependent upon the desired characteristics of the food in the packaging. Plastic polymers, equipment that evacuates or gas flushes, and mixtures of carbon dioxide, nitrogen, and/or oxygen are common in MAP systems for muscle foods, fruits, and vegetables, bakery products, dairy products, precooked foods, beverages, intermediate-moisture foods, and dried foods. The microbial safety of food in MAP is dependent upon the types and levels of pathogenic microorganisms present for growth and/or toxin production and the conditions in the package and food. Therefore, there is always a concern for foodborne illness risk from Clostridium botulinum growth and toxin production in anaerobic MAP if there is temperature abuse, from enterotoxic Escherichia coli and Listeria monocytogenes growth in refrigerated foods in MAP, and from other pathogenic microorganisms associated with specific foods and environments. Technologies of smart, intelligent, and active packaging systems are available for sensing food and environment conditions; altering the environment and thus the product through absorption or emission of different gases and compounds; and incorporating safe antioxidant and antimicrobial agents into packaging materials, packets/sachets/pads for inclusion in the package, or during the packaging process. This chapter will summarize the packaging equipment, materials, and gases for MAP; foods that are packaged in MAP; and recent technologies used in conjunction with MAP

Advancements in meat packaging

© 2017 Elsevier Ltd Packaging of meat provides the same or similar benefits for raw chilled and processed meats as other types of food packaging. Although air-permeable packaging is most prevalent for raw chilled red meat, vacuum and modified atmosphere packaging offer longer shelf life. The major advancements in meat packaging have been in the widely used plastic polymers while biobased materials and their integration into composite packaging are receiving much attention for functionality and sustainability. At this time, active and intelligent packaging are not widely used for antioxidant, antimicrobial, and other functions to stabilize and enhance meat properties although many options are being developed and investigated. The advances being made in nanotechnology will be incorporated into food packaging and presumably into meat packaging when appropriate and useful. Intelligent packaging using sensors for transmission of desired information and prompting of subsequent changes in packaging materials, environments or the products to maintain safety and quality are still in developmental stages

The contribution of wildlife to sustainable natural resource utilization in Namibia : a review

CITATION: Van Schalkwyk, D. L., McMillin, K. W., Witthuhn, R. C. & Hoffman, L. C. 2010. The Contribution of Wildlife to Sustainable Natural Resource Utilization in Namibia: A Review. Sustainability, 2(11):3479-3499, doi:10.3390/su2113479.The original publication is available at http://www.mdpi.com/2071-1050/2/11/3479Namibia is the driest country in sub-Saharan Africa, but well known for its richness in species and sustainable natural resource utilization. The Namibian farming sector consists mainly of extensive farming systems. Cattle production contributes 54% of the livestock sector’s production output, followed by sheep and goats (25%), hides and skins (9%), and other forms of agricultural production (12%). Namibia’s freehold farmers have obtained ownership rights over land and livestock since the early 1900s; commercial rights over wildlife and plants were given to freehold farmers in 1967 and to communal farmers in 1996. Natural resource-based production systems then overtook agricultural production systems and exceeded it by a factor of at least two. The shift from practicing conservation to sustainable utilization of natural resources contributed to the rapid growth of wildlife utilization. The wildlife industry in Namibia is currently the only animal production system that is expanding. There are in total at least two million head of different wildlife species. The broader impact of the utilization of wildlife on the economy is estimated to be around N$ 1.3 billion. Tourism, live sales and trophy hunting, cannot sustain further growth. Wildlife farming could offer better opportunities for ensuring long-term sustainability. As the game meat trade in Namibia is not formalized, harvesting wildlife to satisfy the demand for game meat in export markets is still in its infancy. Sustainable harvesting of wildlife for meat production, however, has the potential to increase earnings to the beneficiaries in the wildlife sector.Publishers' Versio

Combined effects of packaging atmosphere and lactic acid on growth and survival of Listeria monocytogenes in crayfish tail meat at 4°C

The effect of lactic acid on growth and survival of Listeria monocytogenes in crayfish tail meat stored under refrigeration and various gas environments was investigated. Frozen crayfish tail meat was thawed overnight, autoclaved, cooled, and inoculated with approximately 4 log colony-forming units (CFU) of a mixed-strain (Scott A and F5027) L. monocytogenes culture per gram of meat. Inoculated samples were blended with 0, 0.5, 1.0, 1.5. or 2.0% lactic acid and packaged under air, vacuum, or modified atmosphere (74.8% CO2, 10.4% O2, and 14.8% N2) and stored at 4°C for 20 days, Results demonstrated that modified atmosphere packaging inhibited the growth of L. monocytogenes more than air and vacuum packaging at 0 and 1% lactic acid. Microbiol counts declined steadily in crayfish tail meat treated with 2% lactic acid, with no differences among the packaging atmospheres. The lag phase was extended by 8 days in samples treated with 1% lactic acid and modified atmosphere compared to that in air or vacuum packaging Overall, the combination of lactic acid and modified atmosphere had the greatest potential to prevent growth of L. monocytogenes