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This study examines the pharmacokinetics and bioavailability of phlorotannins from Ecklonia cava in rats following intravenous and oral administration. Known for their potent antioxidant, anti-inflammatory and many other bioactivities, these phlorotannins, particularly dieckol, 8,8′-bieckol, and phlorofucofuroeckol-A (PFF-A), were analyzed using high-performance liquid chromatography coupled with tandem mass spectrometry. Intravenous administration at 10 mg/kg allowed detectability in plasma for up to 36 h for dieckol and 8,8′-bieckol, but only 2 h for PFF-A. Oral administration at doses of 100 mg/kg and 1000 mg/kg showed limited detectability, indicating low bioavailability and rapid clearance, particularly for PFF-A. The pharmacokinetic data suggest non-linear increases in the maximum plasma concentration (Cmax) and area under the curve (AUC) with increasing doses, pointing to significant challenges in achieving systemic availability of these eckols through oral administration. This study underscores the necessity for advanced formulation strategies and alternative routes of administration to enhance systemic bioavailability. At the same time, this result also suggests their effects may be through non-systemic pathways such as gut microbiome modulation or lipid-rich tissue targeting. The findings lay a crucial foundation for the further development of Ecklonia cava phlorotannins as therapeutic agents, offering insights into their pharmacokinetic behavior and informing enhancements in future clinical utility.

Transient electronics entails the capability of electronic components to dissolve or reabsorb in a controlled manner when used in biomedical implants. Here, the authors perform a systematic study of the processes of hydrolysis, bioabsorption, cytotoxicity and immunological biocompatibility of monolayer MoS2.

Abstract Porous materials possessing high surface areas are of paramount importance in gas separation and storage, as they can potentially adsorb a large amount of gas per unit of mass or volume. Pore structure and functionality are also important factors affecting adsorbate–absorbent interactions. Hence, efforts have been devoted to developing adsorbents with large accessible surface areas and tunable functionalities to realize improvements in gas adsorption capacity. However, the gas adsorption and storage capacities of porous materials composed of a single type of building unit are often limited. To this end, mixed-dimensional hybrid materials have been developed, as they can contain more gas storage sites within their structures than simple porous materials. In this review, we discuss (1) the methods that have been used to assemble various dimensional building blocks into a range of mixed-dimensional (zero-dimensional–two-dimensional, one-dimensional–two-dimensional, and three-dimensional–two-dimensional) hybrid materials exhibiting synergistic adsorption effects, and (2) these materials’ hydrogen and carbon dioxide adsorption properties and how they are correlated with their accessible surface areas. We conclude by outlining the challenges remaining to be surmounted to realize practical applications of mixed-dimensional hybrid materials and by providing future perspectives.

Transient electronics represents an emerging technology whose defining feature is an ability to dissolve, disintegrate or otherwise physically disappear in a controlled manner. Envisioned applications include resorbable/degradable biomedical implants, hardware-secure memory devices, and zero-impact environmental sensors. 2D materials may have essential roles in these systems due to their unique mechanical, thermal, electrical, and optical properties. Here, we study the bioabsorption of CVD-grown monolayer MoS2, including long-term cytotoxicity and immunological biocompatibility evaluations in biofluids and tissues of live animal models. The results show that MoS2 undergoes hydrolysis slowly in aqueous solutions without adverse biological effects. We also present a class of MoS2-based bioabsorbable and multi-functional sensor for intracranial monitoring of pressure, temperature, strain, and motion in animal models. Such technology offers specific, clinically relevant roles in diagnostic/ therapeutic functions during recovery from traumatic brain injury. Our findings support the broader use of 2D materials in transient electronics and qualitatively expand the design options in other areas. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates applicability of molybdenum disulfide in thin-film transistor and circuitry of organic light-emitting diode (OLED) display. it mentions that proposed architecture exhibits 28 times increase in mobility compared to a normal back-gated thin-film transistor, and its potential as a wearable display attached to a human wrist is demonstrated.

Iodothyronine deiodinases play an important role in thyroid hormone regulation in vertebrates. The aim of this study was to clone type II (SgD2) and type III (SgD3) iodothyronine deiodinase cDNA from the goldlined spinefoot ( Siganus guttatus) using 3′- and 5′-rapid amplification of cDNA ends and then to assess their expression patterns in the liver under several experimental conditions by using quantitative real-time PCR. SgD2 (1013 bp) and SgD3 (1492 bp) contained open reading frames of 810 and 804 bp and encoded 270 and 269 amino acids, respectively. They were characterized by an in-frame TGA codon that was considered to be selenocysteine. An abundance of SgD2 and SgD3 mRNA was expressed in several tissues, with an increase at 1200 hours and a decrease at 2400 hours. Food deprivation suppressed the expression of SgD2, but not SgD3. Higher SgD2 and SgD3 mRNA levels in the liver were found in fish reared at 25°C than in those reared at 20 and 30°C. These results suggest that exogenous factors influence the mRNA levels of iodothyronine deiodinase genes in the liver and that transcription of the genes in certain tissues is partially regulated in a circadian manner. [ABSTRACT FROM AUTHOR]

The golden rabbitfish Siganus guttatus is a reef fish with a restricted lunar-synchronized spawning cycle. It is not known how the fish recognizes cues from the moon and exerts moon-related activities. In order to evaluate the perception and utilization of moonlight by the fish, the present study aimed to clone and characterize Period2 ( Per2), a light-inducible clock gene in lower vertebrates, and to examine daily variations in rabbitfish Per2 ( rfPer2) expression as well as the effect of light and moonlight on its expression in the pineal gland. The partially-cloned rfPer2 cDNA (2933 bp) was highly homologous (72%) to zebrafish Per2. The rfPer2 levels increased at ZT6 and decreased at ZT18 in the whole brain and several peripheral organs. The rfPer2 expression in the pineal gland exhibited a daily variation with an increase during daytime. Exposing the fish to light during nighttime resulted in a rapid increase of its expression in the pineal gland, while the level was decreased by intercepting light during daytime. Two hours after exposing the fish to moonlight at the full moon period, the rfPer2 expression was upregulated. These results suggest that rfPer2 is a light-inducible clock gene and that its expression is affected not only by daylight but also by moonlight. Since the rfPer2 expression level during the full moon period was higher than that during the new moon period, the monthly variation in the rfPer2 expression is likely to occur with the change in amplitude between the full and new moon periods. [ABSTRACT FROM AUTHOR]

As the first step in understanding the molecular oscillation of the circa rhythms in the golden rabbitfish Siganus guttatus—a reef fish with a definite lunar-related rhythmicity—we cloned and sequenced a Period gene ( rfPer). The rfPer gene contained an open reading frame that encodes a protein consisting of 1,452 amino acids; this protein is highly homologous to PER proteins of vertebrates including zebrafish. Phylogenetic analyses indicated that the rfPER protein is related to the zebrafish PER1 and PER4. The expression of rfPer mRNA in the whole brain, retina, and liver under light/dark (LD) conditions increased at 06:00 h and decreased at 18:00 h, suggesting that its robust circadian rhythm occurs in neural and peripheral tissues. When daily variation in the expression in rfPer mRNA in the whole brain and cultured pineal gland were examined under LD conditions, similar expression patterns of the gene were observed with an increase around dawn. Under constant light condition, the increased expression of rfPer mRNA in the whole brain disappeared around dawn. The present results demonstrate that rfPer is related to zPer4 and possibly zPer1. The present study is the first report on the Period gene from a marine fish. [ABSTRACT FROM AUTHOR]

Melatonin receptors are expressed in neural and peripheral tissues and mediate melatonin actions on the regulation of circadian rhythms in various species. For overall understanding of ‘circa’ rhythms in the golden rabbitfish, Siganus guttatus, which exhibits restricted lunar-related rhythms and spawns synchronously around the first quarter moon, the aim of the present study was to clone a melatonin receptor (Mellb) cDNA and examine daily variations of Mellb mRNA expression in certain tissues of the rabbitfish. The full-length Mellb cDNA (1808 bp) contained an open reading frame to encode a protein with a length of 354 amino acids, which was highly homologous to a protein of nonmammalian species. Northern blot analysis showed transcripts of Mellb in the brain and retina. Real-time quantitative polymerase chain reaction analysis also revealed expression of Mellb in all tissues tested. Significantly high expression of the gene during daytime was evident in the liver and kidney. When the expression of Mellb was examined in the brain and retina under conditions of light/dark cycles or constant darkness, daily and circadian variations of gene expression with two increases during daytime and nighttime for the brain and a single increase during nighttime for the retina were recognized. Moreover, daily variations in the expression of Mellb were observed in the cultured pineal gland. These results suggest that the melatonin receptor plays a role in integration of melatonin actions in various tissues and that daily variations of Mellb in the neural tissues may be related to regulation of circadian clock. [ABSTRACT FROM AUTHOR]

This study examined the annual and the lunar cycles of ovarian activity in the forktail rabbitfish Siganus argenteus (Quoy & Gaimard, 1825) and the spiny rabbitfish Siganus spinus (Linnaeus, 1758), which were collected from the Chuuk lagoon, Federated States of Micronesia. Gonadosomatic index (GSI) increased in May and June for S. argenteus. For S. spinus, GSI increased in March, and from July to September. During these periods, the ovaries of these species contained oocytes at the tertiary yolk stage or the maturation stage, suggesting that these months are the reproductive season of the two species. During the reproductive season, weekly collection of the fish according to the lunar phase revealed that high GSI occurred around the last quarter moon for S. argenteus and the new moon for S. spinus. In the ovaries, oocytes developed synchronously, and postovulatory follicles, an indicator of spawning, were observed after the respective moon phase, suggesting that these species are restricted lunar-synchronized spawners. Comparisons of the reproductive activity of the two rabbitfishes in the Chuuk lagoon with that in Okinawa waters revealed that there is a geographic difference in the reproductive activity between habitats. However, the lunar phase for exertion of synchronous gonadal maturation and spawning is common in both regions. [ABSTRACT FROM AUTHOR]

The annual reproductive and the lunar-related spawning cycles of the pencil-streaked rabbitfish Siganus doliatus collected from Chuuk Lagoon, Federated States of Micronesia, were examined histologically. Monthly collection of this species revealed that ovaries with developing oocytes containing yolk were observed from February to May and in August and September. Weekly collection of the fish showed that ovarian development and spawning after the first quarter moon were repeated during the reproductive season, suggesting that S. doliatus is a restricted lunar-synchronized spawner and releases gametes around the time of the first quarter moon. [ABSTRACT FROM AUTHOR]

We demonstrate flexible 3 dB and 6 dB microwave attenuators using multilayer graphene grown by the chemical vapor deposition method. On the basis of the characterized results of multilayer graphene and graphene–Au ohmic contacts, the graphene attenuators are designed and measured. The flexible graphene-based attenuators have 3 dB and 6 dB attenuation with a return loss of less than −15 dB at higher than 5 GHz. The devices have shown durability in a bending cycling test of 100 times. The circuit model of the attenuator based on the characterized results matches the experimental results well. [ABSTRACT FROM AUTHOR]