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The Discovery of the GSH Receptor in Hydra and Its Evolutionary Significance
Published in Christopher A. Shaw, Glutathione in the Nervous System, 2018
The following are the main features of the assay we developed: A hydra in the absence of glutathione is shown in Fig. 1 A: the mouth is closed, and the tentacles are outstretched and nearly motionless. After glutathione is added, the tentacles begin to writhe and sweep inwards toward the central vertical axis of the animal (Fig. 1 B). Next, the tentacles bend toward the mouth, and the mouth opens (Fig. 1 C). Shown in this composite drawing (Fig. 1 C) are the various positions that a tentacle takes before contracting. These movements, culminating in mouth opening, usually all take place within one-half minute. Figure 1D shows how a hydra looks during the greater portion of the feeding response, its mouth open wide and the tentacles in various phases of contraction. Frequently, the tips of the tentacles are observed within the hydra’s mouth, as shown in Fig. 1C and D.
Beach lifeguard first aid
Published in Mike Tipton, Adam Wooler, The Science of Beach Lifeguarding, 2018
For stingrays, stonefish, lionfish, Portuguese man-of-war (Physalia physalis), weever fish and sea urchins, immersion in hot water can provide pain relief. All tropical Australian jellyfish, including the box jellyfish (Chironex fleckeri), should be treated with decontamination from cold seawater, followed by 5% acetic acid (vinegar). If acetic acid is unavailable, then a slurry of baking soda and water can be used. There is some conflicting literature that acetic acid may increase the amount of venom released by some species; however, more rigorous evidence exists that it stops the stinging process. There are conflicting studies on hot water immersion versus application of cold packs and cold water. A reasonable approach for all other jellyfish is to attempt hot water immersion for 20 minutes after application of 5% acetic acid (vinegar), or application of cold if more readily available. Decontamination by removing tentacles should be performed while wearing gloves to prevent injury to the lifeguard. Pressure bandages should be avoided and may increase the amount of venom released.
Profile of Toxic Pufferfish
Published in Ramasamy Santhanam, Biology and Ecology of Toxic Pufferfish, 2017
Description: Body of this species is elongated with somewhat bulky head and pectoral region. It is rounded dorsally and flattened ventrally, tapering to the moderately thickened caudal peduncle. Mouth is small and terminal on a protruding snout. Lips are moderately thick, covered with numerous short papillae. Chin is lacking. Nasal organ is a small, simple tentacle which is slightly expanded distally. Eye is small, round and completely adnate. Pectoral fins are more or less bilobed, the median rays shorter than those above or below. Body spines are short, multirooted and are densely scattered over body from mid snout to dorsal fin, sometimes continuing sparsely on anterior part of caudal peduncle. Dorsal base color is brown to dark brown with numerous iridescent blue spots. Three brown to dark-brown bars extend down each side of body, first passing obliquely through eye to lower jaw, joining with corresponding bar from other side, second enveloping gill slit and pectoral base and bifurcating ventrally, and the third just posterior to pectoral fin. Interspaces on side are pale brown to cream. Ventral surface is white with ventrolateral surface lined with yellow. Adult males possess a black to brown circular blotch above pectoral base, surrounded or partly surrounded by an iridescent blue line or series of spots. Fins are yellow to orange and caudal fin is more dusky with lowermost rays blackish. It reaches a total length of 18 cm.
Gut microbiota: what is its place in pharmacology?
Published in Expert Review of Clinical Pharmacology, 2019
Aleksandra Tarasiuk, Jakub Fichna
In the stomach, which is lined with a single layer of squamous epithelium, its cells are responsible for the secretion of hydrochloric acid, digestive enzymes, and mucus. In the small intestine, a thick type of epithelium is present – single-layer cubic or columnar, constituting a natural protective barrier. It performs both secretory and transport functions, related to the absorption of many substances. The epithelial surface in the small intestine is characterized by the presence of numerous cavities and folds, formed by glands, crypts, and villi, which is an expression of the adaptation of this part of the GI tract to the function performed. The epithelium of the intestinal villi consists of capillary epithelial cells. It is formed by single tentacles, so-called microvilli that also increase its surface. Under the epithelium of the villi, in the middle of the lamina propria, a network of lymph vessels is located. Enterocytes are alternated with intestinal goblet cells secreting mucus. The core of the intestinal villi consists of cylindrical, straight cavities that extend to the muscular layer but are not penetrating. At the bottom of the crypts there are stem cells, and above them, Paneth cells, secreting antibacterial lysozyme. The epithelium located above the lymphoid cells of the intestine, in which Peyer’s patches are present, is a characteristic area of the intestine due to the microcavities and microfold cells located there. The main role of these cells is both the recovery of shortened or irregular villi or pits, as well as the transport of microorganisms from the intestinal lumen to deeper epithelial layers.
Upcycling of jellyfish (Nemopilema nomurai) sea wastes as highly valuable reducing agents for green synthesis of gold nanoparticles and their antitumor and anti-inflammatory activity
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Eun-Young Ahn, Su Jung Hwang, Myung-Jin Choi, Seonho Cho, Hyo-Jong Lee, Youmie Park
Nemopilema nomurai (Scyphozoa, Rhizostomeae) that is one of giant jellyfish have asexual and sexual reproduction phases in a life cycle. They are able to proliferate exponentially when the ecological environment is proper for their reproduction [20]. Currently, global climate change is likely to lead the massive appearance of the jellyfish. N. nomurai usually appear in the Yellow Sea, the East Sea and the East China Sea from late spring to the beginning of winter. The massive appearance results in the damage of marine ecosystem and further leads to a lot of problems such as decline in income of fisheries and safety accident of the summer visitors. Especially, the tentacles of jellyfish have been regarded as highly toxic poisons such as cardiovascular and pore-forming toxins. Recently, however, jellyfish is started to be recognized as a beneficial resource having anti-microbial, anti-inflammatory, and anti-oxidative properties [21]. To date, jellyfish extracts are reported to have various potential effects as novel bioactive therapeutic agents. However, it is largely unknown whether the aqueous extract of N. nomurai tentacle can be used for the green synthesis of nanomedicine as major ingredients and what function the AuNPs represents.
Delayed deep dermal necrosis after jellyfish sting in a 4-year-old female infant
Published in Case Reports in Plastic Surgery and Hand Surgery, 2018
Diana Desax-Willer, Thomas Krebs, Samuel Christen
A 4-year-old female infant, the daughter of a Thai mother and a Swiss father, was stung by a jellyfish during their holidays in Hua Hin, Thailand. The incident occurred at the beach in shallow water. The animal was described to be transparent and had long tentacles (approximately 1 m). The girl immediately experienced intense pain and developed reddish sting marks on her legs. Vinegar was immediately poured over the sting marks. Four hours later, the girl was treated at the local hospital with an unknown topical cream. Five days later, she was presented to the surgical department of a hospital in Bangkok (Figures 1, 2). She continued to report pain. According to information provided by the attending doctor, the skin marks were dry, without signs of infection, and there was a mild swelling of the left leg. Systemic therapy with oral prednisone and local treatment with Silvex® cream (containing sulfadiazine and silver) was initiated. The girl developed intense local itching, scabbing occurred, and perifocal redness increased.