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551.
Background: There has been a rapid rise in allergic disorders across the globe. This has increased research into the determinants of allergy development, to identify factors that may be manipulated to mitigate risk. An opportune window in immunological development appears to exist in early life whereby certain exposures may promote or prevent the development of an allergic disposition. Furthermore, factors that affect the composition and diversity of the microbiome in early life have been explored. In this review, we discuss current literature and recommendations relating to exposures that may prevent allergy development or promote tolerance. Risk factors and recommendations: Delivery by caesarean section, omission of breastfeeding, vitamin D insufficiency, and environmental exposures, such as cigarette smoke exposure, all increase the risk of an allergic predisposition. Dietary diversity during pregnancy, lactation, and in infancy is protective. Breastfeeding for at least 4 months reduces the risk of eczema. Recommendations for food-allergen exposure has shifted from delayed introduction to early introduction as a tolerance-inducing strategy. Supplements such as probiotics and vitamins during pregnancy and infancy have yet to produce conclusive results for allergy prevention. Emollient use in infancy has not been shown to be protective against eczema or food allergy. 相似文献
552.
W K Lam M Siemen J C Lee L T Yam C Y Li L E Wold 《Clinical physiology and biochemistry》1987,5(6):305-314
The tartrate-sensitive prostatic acid phosphatase, bands 2 and 4, are found in the soluble cytosol, and absent in the polysome of the prostate, while the tartrate-resistant acid phosphatase band 5 is present in the polysome and the soluble cytosol of hairy cells. The mRNA isolated from the prostate catalyzes the incorporation of 3T leucine into a protein different from that of bands 2 and 4. On the other hand, the mRNA isolated from the hairy cells catalyzes the incorporation of 3T leucine into band 5. The different biosynthetic mechanism of these two types of acid phosphatases are discussed in light of their different clinical significance. 相似文献
553.
Arianna Mancuso Ruth Yam Fiorella Prada Marco Stagioni Stefano Goffredo Aldo Shemesh 《Geobiology》2023,21(1):119-132
Stable isotopes in mollusc shells, together with variable growth rates and other geochemical properties, can register different environmental clues, including seawater temperature, salinity and primary productivity. However, the strict biological control over the construction of biominerals exerted by many calcifying organisms can constrain the use of these organisms for paleoenvironmental reconstructions. Biologically controlled calcification is responsible for the so called vital effects that cause a departure from isotopic equilibrium during shell formation, resulting in lower shell oxygen and carbon compared to the equilibrium value. We investigated shell oxygen and carbon isotopic composition of the bivalve Chamelea gallina in six sites along with a latitudinal gradient on the Adriatic Sea (NE Mediterranean Sea). Seawater δ18O and δ13CDIC varied from North to South, reflecting variations in seawater temperature, salinity, and chlorophyll concentration among sites. Shell δ18O and δ13C differed among sites and exhibited a wide range of values along with the ~400 km latitudinal gradient, away from isotopic equilibrium for both isotopes. These results hampered the utilization of this bivalve as a proxy for environmental reconstructions, in spite of C. gallina showing promise as a warm temperature proxy. Rigorous calibration studies with a precise insight of environment and shell growth are crucial prior to considering this bivalve as a reliable paleoclimatic archive. 相似文献
554.
Jonathan Diep Huong Le Kim Le Ewelina Zasadzinska Jasmine Tat Pheng Yam Ryan Zastrow Natalia Gomez Jennitte Stevens 《Biotechnology progress》2021,37(6):e3192
Cell line development (CLD) represents a critical, yet time-consuming, step in the biomanufacturing process as significant resources are devoted to the scale-up and screening of several hundreds to thousands of single-cell clones. Typically, transfected pools are fully recovered from selection and characterized for growth, productivity, and product quality to identify the best pools suitable for single-cell cloning (SCC) using limiting dilution or fluorescence-activated cell sorting (FACS). Here we report the application of the Berkeley Lights Beacon Instrument (BLI) in an early SCC process to accelerate the CLD timeline. Transfected pools were single-cell cloned when viabilities reached greater than 85% or during selection when viabilities were less than 30%. Clones isolated from these accelerated processes exhibited comparable growth, productivity, and product quality to those derived from a standard CLD process and fit into an existing manufacturing platform. With these approaches, up to a 30% reduction in the overall CLD timeline was achieved. Furthermore, early process-derived clones demonstrated equivalent long-term stability compared with standard process-derived clones over 50 population doubling levels (PDLs). Taken together, the data supported early SCC on the BLI as an attractive approach to reducing the standard CLD timeline while still identifying clones with acceptable manufacturability. 相似文献