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11.
Reactive oxygen species (ROS) are involved in the pathophysiology of fulminant hepatic failure. Therefore, we developed polyethylene glycol-conjugated bovine serum albumin with multiple reduced thiols (PEG-BSA-SH) for the treatment of fulminant hepatic failure. As a long-circulating ROS scavenger, PEG-BSA-SH effectively scavenged highly reactive oxygen species and hydrogen peroxide in buffer solution. PEG-BSA-SH showed a long circulation time in the plasma after intravenous injection into mice. Fulminant hepatic failure was induced by intraperitoneal injection of lipopolysaccharide and d-galactosamine (LPS/d-GalN) into mice. The LPS/d-GalN-induced elevation of plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels was significantly inhibited by a bolus intravenous injection of PEG-BSA-SH. Furthermore, the changes in hepatic lipid peroxide and hepatic blood flow were effectively suppressed by PEG-BSA-SH. In contrast, l-cysteine, glutathione, and dithiothreitol, three traditional reduced thiols, had no statistically significant effects on the serum levels of ALT or AST. These findings indicate that PEG-BSA-SH is a promising ROS scavenger and useful in the treatment of fulminant hepatic failure. 相似文献
12.
13.
Lars Terenius Björn Johansson 《Biochemical and biophysical research communications》2010,396(1):140-142
This mini-review outlines the opioid systems and their roles primarily as related to reward and compulsive drug/alcohol intake. The central role is taken by the mu-opioid receptor, target for opiate analgesics and also a central target in compulsive alcohol abuse, alcoholism. The mu-opioid receptor and the cognate opioid neuropeptides from proenkephalin and proopiomelancortin are members of a superfamily of opioid systems, each with unique and still to be defined roles in the central nervous system. 相似文献
14.
The results of a detailed analysis of 100 supernumerary limbs generated by 180° ipsilateral rotation (on the same limb stump) of regeneration blastemas is presented. The limbs were analyzed in terms of their position of origin, frequency, cartilage structure by Victoria blue staining, and muscle structure by serial sections. Single, double, or triple supernumeraries can be produced at no unique position of origin, although the posterodorsal quadrant was preferred. Four classes of supernumerary limbs were generated by such operations—normal; double dorsal or double ventral; part normal/part mirror imaged; part normal/part inverted in approximately equal frequencies. After amputation of these supernumeraries the same muscle patterns are faithfully regenerated. A hypothesis to explain the production of these abnormal limbs is proposed based on the observed phenomenon of fusion of supernumerary blastemata, but their regenerative behaviour presents problems for current models of pattern formation. Similar results have been obtained with developing limb buds and the relation between development and regeneration is discussed. 相似文献
15.
Tomohide Yasunaga 《Journal of Asia》2021,24(1):235-245
The fauna of the nasocorine plant bug genus Campylomma Reuter from the Oriental Region, including subtropical Japanese Ryukyu Islands (Okinawa Island of Southwest Islands-group) and Taiwan is updated. Three new species are herein described, C. astica n. sp. (from Okinawa and Taoyuan, Taiwan), C. hibiscicola n. sp. (Bangkok, Thailand) and C. nanrenana n. sp. (Pingtung, Taiwan). Of these, C. astica and C. hibiscicola, were observed to have cryptic habitat-preference, inhabiting bracts, stipules or flower buds of the sea (or coastal) hibiscus, Hibiscus tiliaceus (L.) (Malvaceae), planted for landscaping at urbanized zones. An updated checklist of the 22 Oriental Campylomma species is provided. 相似文献
16.
Changsung Kim 《BMB reports》2015,48(5):256-265
Cardiovascular and neurodegenerative diseases are major health threats in many
developed countries. Recently, target tissues derived from human embryonic stem
(hES) cells and induced pluripotent stem cells (iPSCs), such as cardiomyocytes
(CMs) or neurons, have been actively mobilized for drug screening. Knowledge of
drug toxicity and efficacy obtained using stem cell-derived tissues could
parallel that obtained from human trials. Furthermore, iPSC disease models could
be advantageous in the development of personalized medicine in various parts of
disease sectors. To obtain the maximum benefit from iPSCs in disease modeling,
researchers are now focusing on aging, maturation, and metabolism to
recapitulate the pathological features seen in patients. Compared to pediatric
disease modeling, adult-onset disease modeling with iPSCs requires proper
maturation for full manifestation of pathological features. Herein, the success
of iPSC technology, focusing on patient-specific drug treatment,
maturation-based disease modeling, and alternative approaches to compensate for
the current limitations of patient iPSC modeling, will be further discussed.
[BMB Reports 2015; 48(5): 256-265] 相似文献
17.
《Harmful algae》2017
Azaspiracids (AZA) are a group of food poisoning phycotoxins that are known to accumulate in shellfish. They are produced by some species of the planktonic dinophycean taxon Amphidomataceae. Azaspiracids have been first discovered in Ireland but are now reported in shellfish from numerous global sites thus showing a wide distribution. In shellfish samples collected in 2009 near Huelva (Spain), AZA was also found along the Andalusian Atlantic coast for the first time. Analysis using LC–MS/MS revealed the presence of two different AZA analogues in different bivalve shellfish species (Chamelea gallina, Cerastoderma edule, Donax trunculus, and Solen vagina). In a number of samples, AZA levels exceeded the EU regulatory level of 160 μg AZA-1 eq. kg−1 (reaching maximum levels of >500 μg AZA-1 eq. kg−1 in Chamelea gallina and >250 μg AZA-1 eq. kg−1 in Donax trunculus) causing closures of some local shellfish production areas. One dinophyte strain established from the local plankton during the AZA contamination period and determined as Amphidoma languida was in fact toxigenic, and its AZA profile disclosed it as the causative species: it contained AZA-2 as the main compound and the new compound AZA-43 initially detected in the shellfish. AZA-43 had the same mass as AZA-3, but produced different collision induced dissociation (CID) spectra. High resolution mass spectrometric measurements indicated that there is an unsaturation in the H, I ring system of AZA-43 distinguishing it from the classical AZA such as AZA-1, -2, and -3. Furthermore, the Spanish strain was different from the previously reported AZA profile of the species that consist of AZA-38 and AZ-39. In molecular phylogenetics, the Andalusian strain formed a monophyletic group together with other strains of Am. languida, but ITS sequences data revealed surprisingly high intragenomic variability. The first Andalusian case of AZA contamination of shellfish above the EU regulatory limit reported here clearly revealed the risk of azaspiracid poisoning (AZP) for this area and also for the Atlantic coast of Iberia and North Africa. The present study underlines the need for continuous monitoring of AZA and the organisms producing such toxins. 相似文献
18.
Two new oleanane-type triterpene saponins, identified as 16α-hydroxy-22-O-angeloyl-23-formyl-28,31-dihydroxymethylene-olean-12-ene-3β-O-{β-d-galactopyranosyl-(1 → 2)[β-d-xylopyranosyl-(1 → 2)-α-l-arabinopyranosyl(1 → 3)]-β-d-glucopyranosiduronic acid} (oleiferasaponin B1, 1) and 22-O-hydrocinnamoyl-23-formyl-28-dihydroxymethylene-olean-12-ene-3β-O-{β-d-glucopyranosyl-(1 → 2)[β-d-xylopyranosyl-(1 → 2)-α-l-arabinopyranosyl(1 → 3)]-β-d-glucopyranosiduronic acid} (oleiferasaponin B2, 2), were isolated from the seed cake of Camellia oleifera Abel. Their structures were established by extensive 1D- and 2D-NMR experiments along with TOF-MS analysis and acid hydrolysis. The cytotoxicity of the isolated compounds was evaluated in four human carcinoma cell lines: A 549, SK-OV-3, SK-MEL-2 and HCT15. Both compounds 1 and 2 exhibited significantly cytotoxic activity with IC50 values of 18.5 μM (A549), 11.3 μM (SK-OV-3), 13.9 μM (SK-MEL-2) and 1.6 μM (HCT15) for 1 and IC50 values of 8.4 μM (A549), 6.3 μM (SK-OV-3), 9.2 μM (SK-MEL-2) and 0.8 μM (HCT15) for 2. In addition, compound 2 showed more effective cytotoxic activity than compound 1. 相似文献
19.
We review the New Caledonian representatives of the Australasian endemic hydroptiline genus Acritoptila, based on examination of a considerable collection of material in the Swedish Museum of Natural History and of types of previously established species. A key for identification of males is given and includes 3 species newly described here: A. parallela
sp. n., A. forficata
sp. n. and A. macrospina
sp. n. For all New Caledonian species, male genitalia are illustrated, and for 5 associated females, distinctive features are illustrated and described. 相似文献
20.
Caroline S. Page Franz M. Matschinsky Paule E. Lacy Susan Conant 《Biochimica et Biophysica Acta (BBA)/General Subjects》1977,497(2):408-414
Electrophysiological studies of cultured rat pancreatic β-cells using intracellular microelectrodes show that exogenous insulin over the range of 0.1–10.0 μg/ml inhibits the electrical activity due to 27.8 mM glucose in a dose-related manner. This inhibitory effect is manifested by a mean increase of the membrane potential from about ?20 to ?30 mV and inhibition of the manner of cells impaled showing spike activity from 60 to less than 10%. The inhibitory influence of insulin is rapid occuring within 5 min for the highest level used. The results provide evidence for a negative feedback role of insulin in regulating its own release. 相似文献