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Gastric secretions are crucial for food breakdown during digestion. Changes in intragastric pH due to gastric secretions are influenced by meal properties, such as composition, particle size, structure, buffering capacity, and mixing of the meal with gastric secretions. The use of in vitro digestion models has increased recently, however more physiologically-relevant digestion models are needed to better mimic the gastrointestinal tract. The objective of this study was to examine different gastric secretion conditions using a dynamic in vitro digestion model to understand their impact on intragastric pH and protein digestion. Whey protein dispersions were made at two protein concentrations (10% w/v and 30% w/v) and were subjected to gastric digestion. Gastric secretions were set to be at constant rate (2.75 mL/min) or variable rate (1.5 – 9.0 mL/min; based on the intragastric pH). In digestions of 30% w/v dispersion, the digesta pH after 60 min was high (average 4.3 ± 0.3), resulting in low pepsin activity (5.6 ± 0.1% of the maximum) and protein degree of hydrolysis (0.3 ± 0.0% degree of hydrolysis), compared to digestions of 10% w/v dispersions. After 90 min of digestion, the pepsin activity in digesta of 30% w/v dispersions increased to 56.1 ± 0.2%, mainly due to the decrease in the emptied digesta pH (average 2.7 ± 0.2). Protein concentration and gastric emptying played an important role on intragastric pH. Further work is needed to develop a mechanistic understanding between food initial properties, gastric emptying rate, gastric secretions, pH changes, and nutrient digestibility during digestion to study the impact of hydrocolloid dispersions properties on human health.

Fusarium is usually thought to cause soybean root rot, which results in a large quantity of annual yield loss in soybean production, by its secretions including Fusarium toxins and cell wall degrading enzymes, but not by the conidia themselves that do not underlie any virulence so far. Here we report that the conidia of one Fusarium solani isolate are able to be virulent to soybean and make soybean seedlings wilted alone. We isolated them from the wilted plants in a soybean-production field and molecularly identified 17 Fusarium isolates through phylogenetic analysis. Of them, except for one isolate that showed diversity of virulence to different soybeans (virulent to one soybean whereas avirulent to another soybean), the others were all virulent to the two tested soybeans: both conidia cultures and secretions could make soybean seedlings wilted at 5 days post infection, and their virulence had dosage effects that only conidia cultures of at least 5×106 conidia mL–1 could show virulence to soybean; however, the sole conidia of the F. solani isolate #4 also exhibited virulence to soybean and could make soybean seedlings wilted. Finally, we developed the specific cleaved amplified polymorphic sequences (CAPS) markers to easily differentiate Fusarium isolates. The isolate #4 in this work will likely be used to investigate the new mechanism of virulence of Fusarium to soybean.

The cumulus oophorus is a structure that surrounds the mammalian egg and plays a key role in fertilization. However, very little is known with regards to how secretions from the cumulus cells can specifically promote fertilization. We hypothesized that secretions from bovine cumulus cells, and the reduction of oxygen stress by metabolic change, would enhance the fertilization capacity of sperm during in vitro fertilization (IVF) procedures. To prove our hypothesis, sperm were pre-incubated in chemically defined capacitation media containing methyl-beta-cyclodextrin and used to inseminate cumulus cell oocyte complexes, or denuded oocytes, with some components. While sperm capacitation was induced in capacitation media, fertilization was impeded by the removal of cumulus cells from cumulus cell oocyte complexes. Secretions from cumulus cells promoted the formation of two pronuclei via a filter and the fertilization of denuded oocytes was dramatically enhanced with hyaluronate, low oxygen concentration, or progesterone in fertilization media (P < 0.05). This demonstrates that these factors-maintained sperm motility and capacitation or enhanced the hyper-activation of capacitated sperm (P < 0.05). We conclude that cumulus cells secrete progesterone, hyaluronate and undergo metabolic events to reduce oxidative stress in fertilization media. These phenomenons help to improve the fertilization capacity of sperm. We believe that this study makes a significant contribution to our understanding of the function of cumulus cells during fertilization in animals and humans., Competing Interests: Declaration of competing interest We declare that no conflict of interest could be perceived as prejudicing the impartiality of the research reported., (Copyright © 2022. Published by Elsevier Inc.)

Surface enhanced Raman scattering (SERS) spectra of bacteria were obtained using citrate (capped) and borohydride (uncapped) generated silver nanoparticles (Ag NPs).The observed differences in SERS spectra are attributed to the manner in which these Ag NPs interact with bacteria. Capped Ag NPs are able to partition through the surface polysaccharides of the bacterial cell to bind to the inner and outer cell membranes, as well as the periplasmic space between them. The resultant spectra show contributions due to the components of the cell envelope and cellular secretions. Uncapped Ag NPs are unable to partition through the polysaccharide outer structures of the cells. Spectral features observed for these uncapped Ag NPs are secretions primarily due to the metabolites of purine degradation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Respiratory failure (RF) can be attributed to a plethora of neuromuscular diseases (NMDs) and manifests clinically in a multitude of overt or more subtle ways. The basic principles of pathophysiology, diagnosis and treatment of neurologic diseases and of RF apply concomitantly to this subset of patients. Various entities should be approached according to the latest evidence-based recommendations. Treatment follows the natural disease progression, from minimal respiratory assistance to mechanical ventilation (MV). A comprehensive treatment plan has to be formulated that takes into consideration the patient's wishes., (© 2014 Elsevier B.V. All rights reserved.)